201630993
Colletotrichum Gloesporioides Inhibition In Situ by Chitosan-Ruta graveolens Essential Oil Coatings: Effect on Microbiological, Physicochemical, and Organoleptic Properties of Guava (Psidium guajava L.) during Room Temperature Storage
Guava is a fruit appreciated worldwide for its high content of bioactive compounds. However, it is considered a highly perishable fruit, generally attacked by pathogenic species such as the fungi Colletotrichum gloeosporioides, which causes anthracnosis. To diminish the losses caused by pathogenic fungi, coatings of chitosan (CS) with Ruta graveolens essential oil (RGEO) in different concentrations (0.5, 1.0, 1.5% v/v) were applied in situ and their effects on the physical properties and microbiological quality of the guavas were studied. The CS+RGEO coated fruits exhibited better physicochemical behavior and lower microbiological decay as compared to the uncoated guavas, demonstrating the effectiveness of the coatings, especially those with 1.5% of RGEO content. All the fruits coated had greater acceptance and quality than the controls, being more those with essential oil incorporation. In situ investigation of C. gloesporioides infection of guavas demonstrated that the CS+RGEO coated guavas showed a high percentage of inhibition in the development of anthracnose lesions. In the present investigation, an alternative method has been proposed to extend the stability of the guavas fruit up to 12 days with application in the food industry.
104035221
Postharvest losses of fruit and vegetables during retail and in consumers’ homes: Quantifications, causes, and means of prevention
Abstract The issue of food loss and waste (FLW) reduction has recently achieved much public attention as part of worldwide efforts to combat global hunger and improve food security. Studies conducted by various international and national organizations led by the FAO indicated that about one third of all food produced on the planet and about a half of all fruit and vegetables (FV 2) Quantifications of FV 3) Causes and consumer decisions related to FV 4) Emerging new technologies for prevention of FV 5) Other means to reduce F&V losses, including consumer awareness campaigns, advertisement of home storage instructions and policy and legislative measures. Due to the great importance of reducing F&V losses, we encourage postharvest researchers to become more engaged with logistics and food supply-chain operations, and to conduct multidisciplinary research incorporating consumer behavior studies into postharvest research.
133782919
Postharvest Diseases of Fruits and Vegetables and Their Management
Abstract Fungi and bacteria cause several postharvest diseases in fruits and vegetables during storage and transportation. The infection is caused by these pathogens either during preharvest stage at field or after harvesting during storage and transportation. For management of postharvest diseases of fruits and vegetables, three basic approaches like prevention of infection, elimination of incipient or latent infection and prevention of spread of the pathogen in the host tissue is being followed. Physical, chemical, and biological methods are used to manage postharvest diseases but they have some limitations individually. However, the efficacy of these methods can be improved by combining two or three methods of postharvest treatments together to reduce postharvest losses and also enhance shelf life of produce.
83919278
Chitosan films and coatings prevent losses of fresh fruit nutritional quality: A review
Abstract Background Consumption of fruits and vegetables, that are rich in antioxidant vitamins and polyphenols, can decrease the risk of the development of age-related chronic diseases. A gradual decline in moisture, sensory properties, vitamin C and polyphenols contents was observed during fruits and vegetables storage. Scope and approach The recent studies on the effect of chitosan-based coatings on the changes of nutritional quality of fruits and vegetables during postharvest storage have been summarized in this review. The latest data of the application of chitosan-based coatings for prevention of the decrease in contents of natural antioxidants ascorbic acid, anthocyanins, and total polyphenols in various fruits and vegetables during postharvest storage have been reviewed. The mechanisms of action and the role of polyphenols and vitamin C in prevention of age-related diseases has been also discussed. Key findings and conclusions Barrier and mechanical properties of chitosan-based films and coatings can be improved by the development of nanocomposite chitosan films and coatings incorporating also rosemary, sunflower, lavender, olive, and carp oils. Layer-by-layer self assembly can be used in the formation of multinanolayer edible coatings.
13858027
Colletotrichum gloeosporioides : An Anthracnose Causing Pathogen of Fruits and Vegetables
Colletotrichum species are present in both tropical and subtropical regions of the world. But Colletotrichum gloeosporioides is most important pathogen and belongs to order melanconiales. The complete genome of this pathogen is not yet sequenced but various genes are identified which involved in pathogenesis and host defense. The optimum temperature for growth of this pathogen is 25-28°C, and pH 5.8-6.5. It is usually inactive in dry season but during favorable conditions it causes anthracnose disease to large number of economic crops amongst which mango anthracnose is important as far as losses caused by pathogen is concerned. First of all pathogen establish interaction with host by producing melanized appressorium and then penetrate the host cuticle. After penetration, infection vesicles and primary hyphae are formed. Later, secondary hyphae developed and spread to kill the host cell. Colletotrichum gloeosporioides follows the hemibiotrophic mode of infection where, biotrophic and necrotrophic phases are sequentially occur. The pathogen produced lesions on leaves, fruit and other parts of plant. Finally these lesions become dark and form concentric ring pattern. Colletotrichum gloeosporioides is also known to infect humans but only few incidents of such infections are known. A number of fungal genes have been identified using mutant screen, which plays role in different stages of infection and can be used as potential targets to devise strategies for controlling anthracnose disease in fields. This review focuses on up to date knowledge of all aspects of C. gloeosporioides biology.
26830378
Exploitation of microbial antagonists for the control of postharvest diseases of fruits: a review
ABSTRACT Fungal diseases result in significant losses of fruits and vegetables during handling, transportation and storage. At present, post-production fungal spoilage is predominantly controlled by using synthetic fungicides. Under the global climate change scenario and with the need for sustainable agriculture, biological control methods of fungal diseases, using antagonistic microorganisms, are emerging as ecofriendly alternatives to the use of fungicides. The potential of microbial antagonists, isolated from a diversity of natural habitats, for postharvest disease suppression has been investigated. Postharvest biocontrol systems involve tripartite interaction between microbial antagonists, the pathogen and the host, affected by environmental conditions. Several modes for fungistatic activities of microbial antagonists have been suggested, including competition for nutrients and space, mycoparasitism, secretion of antifungal antibiotics and volatile metabolites and induction of host resistance. Postharvest application of microbial antagonists is more successful for efficient disease control in comparison to pre-harvest application. Attempts have also been made to improve the overall efficacy of antagonists by combining them with different physical and chemical substances and methods. Globally, many microbe-based biocontrol products have been developed and registered for commercial use. The present review provides a brief overview on the use of microbial antagonists as postharvest biocontrol agents and summarises information on their isolation, mechanisms of action, application methods, efficacy enhancement, product formulation and commercialisation.
52812524
Fruit Decay to Diseases: Can Induced Resistance and Priming Help?
Humanity faces the challenge of having to increase food production to feed an exponentially growing world population, while crop diseases reduce yields to levels that we can no longer afford. Besides, a significant amount of waste is produced after fruit harvest. Fruit decay due to diseases at a post-harvest level can claim up to 50% of the total production worldwide. Currently, the most effective means of disease control is the use of pesticides. However, their use post-harvest is extremely limited due to toxicity. The last few decades have witnessed the development of safer methods of disease control post-harvest. They have all been included in programs with the aim of achieving integrated pest (and disease) management (IPM) to reduce pesticide use to a minimum. Unfortunately, these approaches have failed to provide robust solutions. Therefore, it is necessary to develop alternative strategies that would result in effective control. Exploiting the immune capacity of plants has been described as a plausible route to prevent diseases post-harvest. Post-harvest-induced resistance (IR) through the use of safer chemicals from biological origin, biocontrol, and physical means has also been reported. In this review, we summarize the successful activity of these different strategies and explore the mechanisms behind. We further explore the concept of priming, and how its long-lasting and broad-spectrum nature could contribute to fruit resistance.
131914307
International market of fresh and processed guava: challenges and perspectives for the Mexican case
Guava is one of the most important fruit crops in Mexico. During the last decade average cultivated area has been about 22.8 thousands hectares with an annual production of 291 thousands tons. National mean of guava fruit yield is 13.7 t ha,sup-1, however, it may fluctuate from 2 to 20 t ha-1, depending on the region and between levels of technology used. Approximately 85% of the total production volume is for fresh consumption, while the rest is used for processing at different scales. Most of the commercialization of fresh guava is for the national market and is mainly concentrated in five or six Mexican cities. Nevertheless, those cities represent a potential market of more than 40 millions people. Although guava is produced in more than 20 states of the country, planted area in the states of Michoacan, Aguascalientes and Zacatecas represent an 89% of the total cultivated area. The guava fruit type mainly produced in these regions is called 'Media China', which has a high preference by the consumer because of its nice flavor and pleasant aroma. Recently, guava crop has received more attention by the different stakeholders in the value chain, which allowed reaching important objectives such as the exportation of 15 thousands tons of fresh guava to the United States during the last four years. This was possible because of the campaigns against fruit fly, as well as the approved irradiation treatment. Another important achievement includes the registration and release of the first five Mexican guava cultivars. Even then, some challenges that guava producers in Mexico have to face in the near future are: development and use of more improved cultivars having comparative advantages (fruit size and form, lower seed number, pulp color, ascorbic acid content, total soluble solids, greater firmness, etc.); adoption of better agronomic practices (pruning, nutrition, irrigation, etc.); more environmentally and healthy control of pests; regulation of cropping to ensure more stable production through the whole year and increase fruit quality and uniformity, among others. Besides these technical factors, it is also needed: to enhance organization of guava producers; increase infrastructure (packing and cold storage facilities, etc.); to have more access to technical assistance and better profits for guavas. As long as some of these elements start to be incorporated to the guava production systems, it could be possible to have better perspectives for the future of the Mexican guava.
92374614
Post-harvest shelf-life of banana and guava: Mechanisms of common degradation problems and emerging counteracting strategies
Abstract Banana and guava have short shelf-life at tropical ambient temperature due to climacteric ripening associated changes like rapid softening, senescence spotting, off-odor development, anthracnose, and crown rot disease incidence, and chilling injury occurrence during storage below 13 °C. Commercially post-harvest treatment involved submerging banana and guava in solutions of benomyl or thiabendazole or imazalil. These chemicals are harmful to human health and the environment. Moreover, the fungal pathogens have developed resistance to these fungicides. Hence search of alternative non-chemical, health and environment friendly strategies are major focus of the researchers over the world. Treatment with organic acids, plant extract having antimicrobial properties prevented diseases either by direct action on the fungus or by inducing defense response by increasing the activity of antioxidant enzymes like superoxide dismutase, lipoxygenase, catalase. Degradation of plant parts occurs due to accumulation of reactive oxygen species and enzymatic oxidation of polyphenols during senescence, chilling stress, low oxygen, or high carbon dioxide injury. The deteriorations are evaluated by physical parameters like color change, accumulation of superoxide anion, hydrogen peroxide, malondialdehyde byproducts, accumulation of thiobarbituric reactive compound and ion leakage percentage. The selection of application concentration and treatment duration of 1-methylcyclopropane (1-MCP) treatment which act as an ethylene inhibitor is critical in extending shelf-life of banana and guava. The modified atmosphere, controlled atmosphere storage and edible coating reduced time to occurrence and intensity of climacteric peak respiration, slowed down ripening associated changes, prevented accumulation of reactive oxygen species (ROS) thereby extended shelf-life of guava and banana.
84852032
Effects of chitosan coating on postharvest life and quality of guava (Psidium guajava L.) fruit during cold storage
Abstract The effect of chitosan coating on physiochemical characteristics of ‘pearl’ guava fruit was investigated. The fruit were treated with 0.5, 1.0 and 2.0% chitosan coatings, respectively, and then stored at 11 °C and 90–95% RH. Treatment with 2.0% chitosan significantly reduced firmness and weight loss, delayed changes in chlorophyll and malondialdehyde (MDA) contents and soluble solids content (SSC), and retarded the loss of titratable acidity (TA) and vitamin C during 12 days of storage. This treatment could induce a significant increase in the activities of peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT), and inhibited superoxide free radical (O 2 − ) production. It was suggested that effects of chitosan on increase of antioxidant ability might be beneficial in delaying ripening process in guava fruit during cold storage.
85336217
Biological control of postharvest diseases of fruits and vegetables by microbial antagonists: A review
Postharvest diseases cause considerable losses to harvested fruits and vegetables during transportation and storage. Synthetic fungicides are primarily used to control postharvest decay loss. However, the recent trend is shifting toward safer and more eco-friendly alternatives for the control of postharvest decays. Of various biological approaches, the use of antagonistic microorganisms is becoming popular throughout the world. Several postharvest diseases can now be controlled by microbial antagonists. Although the mechanism(s) by which microbial antagonists suppress the postharvest diseases is still unknown, competition for nutrients and space is most widely accepted mechanism of their action. In addition, production of antibiotics, direct parasitism, and possibly induced resistance in the harvested commodity are other modes of their actions by which they suppress the activity of postharvest pathogens in fruits and vegetables. Microbial antagonists are applied either before or after harvest, but postharvest applications are more effective than preharvest applications. Mixed cultures of the microbial antagonists appear to provide better control of postharvest diseases over individual cultures or strains. Similarly, the efficacy of the microbial antagonist(s) can be enhanced if they are used with low doses of fungicides, salt additives, and physical treatments like hot water dips, irradiation with ultraviolet light etc. At the international level, different microbial antagonists like Debaryomyces hansenii Lodder & Krejer-van Rij, Cryptococcus laurentii Kufferath & Skinner, Bacillus subtilis (Ehrenberg) Cohn, and Trichoderma harzianum Rifai, are being used. Biocontrol products like Aspire, BioSave, and Shemer etc., have also been developed and registered. Although the results of this technology are encouraging, we need to continue to explore potential uses on the commercial scale in different corners of the world.
3458952
Enhanced Removal of a Human Norovirus Surrogate from Fresh Vegetables and Fruits by a Combination of Surfactants and Sanitizers
ABSTRACT Fruits and vegetables are major vehicles for transmission of food-borne enteric viruses since they are easily contaminated at pre- and postharvest stages and they undergo little or no processing. However, commonly used sanitizers are relatively ineffective for removing human norovirus surrogates from fresh produce. In this study, we systematically evaluated the effectiveness of surfactants on removal of a human norovirus surrogate, murine norovirus 1 (MNV-1), from fresh produce. We showed that a panel of surfactants, including sodium dodecyl sulfate (SDS), Nonidet P-40 (NP-40), Triton X-100, and polysorbates, significantly enhanced the removal of viruses from fresh fruits and vegetables. While tap water alone and chlorine solution (200 ppm) gave only <1.2-log reductions in virus titer in all fresh produce, a solution containing 50 ppm of surfactant was able to achieve a 3-log reduction in virus titer in strawberries and an approximately 2-log reduction in virus titer in lettuce, cabbage, and raspberries. Moreover, a reduction of approximately 3 logs was observed in all the tested fresh produce after sanitization with a solution containing a combination of 50 ppm of each surfactant and 200 ppm of chlorine. Taken together, our results demonstrate that the combination of a surfactant with a commonly used sanitizer enhanced the efficiency in removing viruses from fresh produce by approximately 100 times. Since SDS is an FDA-approved food additive and polysorbates are recognized by the FDA as GRAS (generally recognized as safe) products, implementation of this novel sanitization strategy would be a feasible approach for efficient reduction of the virus load in fresh produce.
85166726
Impact of combined postharvest treatments (UV-C light, gaseous O3, superatmospheric O2 and high CO2) on health promoting compounds and shelf-life of strawberries
Abstract Modified atmosphere packaging (MAP), ozone (O 3 ) and ultraviolet-C (UV-C) light, have been suggested as postharvest treatments to control decay of strawberries. However, the influence of these treatments on strawberry phytochemicals has not been thoroughly evaluated. Thus, the impact of individual and combined UV-C light (1 kJ m −2 ), gaseous O 3 (5000 mg L −1 ) and two active MAP conditions (superatmospheric O 2 and CO 2 -enriched atmospheres) on the polyphenols, vitamin C content and shelf-life of strawberries was studied. Samples were taken initially, and after 5, 9 and 12 days of storage and microbial, nutritional and organoleptical qualities were evaluated. None of the evaluated samples showed visual signs of fungal growth after 12 days of storage, including non-treated samples stored in air. However, phenolic contents of UV-C and O 3 treated strawberries were significantly reduced after treatments, mainly due to a significant decrease in procyanidins. Ozonated samples showed the lowest vitamin C contents at the end of storage. On the other hand, when compared with storage in air, strawberries stored under superatmospheric O 2 and CO 2 -enriched concentrations showed lower total phenolic contents after 5 days and a vitamin C reduction after 12 days of storage, accompanied by a more pronounced conversion from reduced to oxidized forms under superatmospheric O 2 . In general, overall quality was good in all samples throughout the shelf-life except for flavour scores of MAP strawberries, which were clearly lower than air-stored samples after 9 and 12 days of storage. No additional effect was observed when combining the postharvest treatments compared with the effect of individual treatments.
85036563
Neutralized electrolyzed water efficiently reduces Fusarium spp. in vitro and on wheat kernels but can trigger deoxynivalenol (DON) biosynthesis
Abstract Fusarium Head Blight (FHB), caused by a blend of Fusarium species, is a destructive fungal disease of wheat and other small grain cereals. FHB has become an important issue in food and feed industry. Moreover, the majority of FHB pathogens have the ability to synthesize a range of mycotoxins. Although several physical and chemical control measures can be taken to control these fungi in the field, research is needed to provide new techniques for control during storage and transport of cereals. Mounting evidence shows that electrolyzed oxidizing water (EOW) has antimicrobial activity and might be a useful alternative for conventional control measures. The objective of the present work, was to investigate the influence of EOW on outgrowth and germination of Fusarium spp. and deoxynivalenol (DON) production. Both an in vitro and in vivo approach were pursued. In a first approach, a screening of the main FHB causing species was conducted. Secondly, the effect of EOW on Fusarium graminearum and the effect on DON biosynthesis was investigated using a trichothecene knockout mutant. These experiments showed an increase in DON levels upon sub lethal amendments of EOW to F. graminearum spores. In addition, the reactive oxygen species H 2 O 2 was shown to govern this induction. Finally, the work was validated on a laboratory scale via an in vivo assay using wheat grains in which the Fusarium outgrowth was measured. The present work demonstrates that EOW has potential to control Fusarium spp. in wheat grains during transport and storage although sub lethal concentrations can result in increased DON biosynthesis.
89346021
Effect of gamma irradiation on some physicochemical properties and bioactive compounds of jujube (Ziziphus jujuba var vulgaris) fruit
Abstract Interest in the protection of bioactive compounds and a safe alternative method for preservation of processed fruits and fruit juices has recently increased significantly throughout the world. There is a distinct lack of information on the profile of bioactive compounds in jujube fruit (e.g. organic acids, anthocyanins, and water-soluble vitamins) and their changes during processing (e.g. gamma irradiation). Therefore, in this study, the effect of gamma irradiation at different doses (0.0, 0.5, 1.0, 2.5 and 5.0 kGy) on some physicochemical properties and the bioactive compounds of jujube fruit was investigated. The total soluble solids (TSSs) values remained unaffected at various doses, while the level of total acidity (TA) showed a slight increase at doses ≥ 2.5 kGy ( p ≤ 0.05). Irradiation up to 2.5 kGy caused a significant increase in the total monomeric anthocyanin and the total phenolic content (about 12% and 6%, respectively), but a significant decrease was observed in both parameters immediately after irradiation at 5 kGy. Moreover, irradiation treatment caused a significant decrease in L* value and a significant increase in a* and b* values ( P ≤ 0.05); however, changes of color were slight until the dose of 5 kGy. Gamma irradiation up to 2.5 kGy had no significant effect on the concentration of malic, citric and succinic acids, while the level of ascorbic acid decreased significantly at all irradiation doses (0–5 kGy). Cyanidin-3, 5-diglucoside was determined as the major anthocyanin in the jujube fruit studied (about 68%), which was reduced significantly when 5 kGy of irradiation was applied (degradation percentage: 27%). The results demonstrated that vitamins C, B 2 and B 1 are the most water-soluble vitamins in jujube fruit, respectively. Vitamins C and B 1 content significantly decreased at all applied doses (0–5 kGy), whereas B 2 content at doses ≤ 2.5 kGy was not significantly affected. The results of this study indicate that gamma irradiation at doses below 2.5 kGy can be successfully used for improving the quality the jujube fruit.
53720300
The Effect of Edible Chitosan Coatings Incorporated with Thymus capitatus Essential Oil on the Shelf-Life of Strawberry (Fragaria x ananassa) during Cold Storage
The strawberry is a fruit appreciated in the food industry for its high content of bioactive compounds. However, it is considered a highly perishable fruit, generally attacked by pests of phytopathogenic origin, which decreases its shelf-life. Normally, to diminish the losses caused by pathogenic microbes, coatings of polysaccharides in combination with natural products like essential oils are applied. In this work, we describe the effect of edible coatings from chitosan (CT) incorporating Thymus capitatus essential oil (TCEO), applied to strawberries stored under refrigeration conditions (5 ± 0.5 °C). Different concentrations of TCEO were applied to chitosan coatings, with different effects on the physical and microbiological properties of the strawberries. All the products had greater acceptance and quality than the controls, being more effective those with essential oil incorporation. It is noteworthy that all the essential oil treatments lead to an increase in the shelf-life of strawberries of up to 15 days. Scanning electron microscopy (SEM) analysis of the microstructure showed a decrease in compactness with TCEO introduction, but without compromising food preservation after 15 days. In addition, treated strawberries delayed the loss of physicochemical and antioxidant properties, due to protection against the microbial development of aerobic mesophylls, molds, and yeasts.
86701782
Effects of Pre‐ and Postharvest Chitosan Treatments to Control Storage Grey Mold of Table Grapes
ABSTRACT: The effectiveness of pre- and postharvest treatments with chitosan (0.1, 0.5, and 1.0%) to control Botrytis cinerea on table grapes was investigated. In postharvest treatments, small bunches dipped in chitosan solutions and inoculated with the pathogen showed a reduction of incidence, severity, and nesting of grey mold, in comparison with the control. Single berries artificially wounded, treated with the polymer, and inoculated with B. cinerea showed a reduced percentage of infected berries and lesion dia. Higher chitosan concentrations demonstrated greater decay reduction. All preharvest treatments significantly reduced the incidence of grey mold, as compared to the control. Table grapes treated with 1.0% chitosan showed a significant increase of phenylalanine ammonia-lyase (PAL) activity. Consequently, besides a direct activity against B. cinerea, chitosan produces other effects contributing to reduce decay.
8109826
Biological effects of essential oils--a review.
Since the middle ages, essential oils have been widely used for bactericidal, virucidal, fungicidal, antiparasitical, insecticidal, medicinal and cosmetic applications, especially nowadays in pharmaceutical, sanitary, cosmetic, agricultural and food industries. Because of the mode of extraction, mostly by distillation from aromatic plants, they contain a variety of volatile molecules such as terpenes and terpenoids, phenol-derived aromatic components and aliphatic components. In vitro physicochemical assays characterise most of them as antioxidants. However, recent work shows that in eukaryotic cells, essential oils can act as prooxidants affecting inner cell membranes and organelles such as mitochondria. Depending on type and concentration, they exhibit cytotoxic effects on living cells but are usually non-genotoxic. In some cases, changes in intracellular redox potential and mitochondrial dysfunction induced by essential oils can be associated with their capacity to exert antigenotoxic effects. These findings suggest that, at least in part, the encountered beneficial effects of essential oils are due to prooxidant effects on the cellular level.
35477405
Essential Oils and Antifungal Activity
Since ancient times, folk medicine and agro-food science have benefitted from the use of plant derivatives, such as essential oils, to combat different diseases, as well as to preserve food. In Nature, essential oils play a fundamental role in protecting the plant from biotic and abiotic attacks to which it may be subjected. Many researchers have analyzed in detail the modes of action of essential oils and most of their components. The purpose of this brief review is to describe the properties of essential oils, principally as antifungal agents, and their role in blocking cell communication mechanisms, fungal biofilm formation, and mycotoxin production.
98795536
Nanoencapsulation of Zataria multiflora essential oil preparation and characterization with enhanced antifungal activity for controlling Botrytis cinerea, the causal agent of gray mould disease
Abstract This study was undertaken to investigate the nanoencapsulation of Zataria multiflora essential oil (ZEO) in chitosan nanoparticles (CSNPs) in order to enhance antifungal activity and stability of the oils against one isolate of Botrytis cinerea Pers., the causal agent of gray mould disease. ZEO was encapsulated by an ionic gelation technique into CSNPs with an average size of 125–175 nm as observed by transmission electron microscopy (TEM). From UV-vis spectrophotometry results, the drug encapsulation and loading efficiency of ZEO decreased from 45.24% to 3.26% and from 9.05% to 5.22%, respectively, upon increasing initial ZEO content from 0.25 to 1 g/g chitosan. In vitro release studies also demonstrated a controlled and sustained release of ZEO for 40 days. The superior performance of ZEO when encapsulated by CSNPs under both in vitro and in vivo conditions in comparison with unmodified ZEO against B. cinerea was revealed. The in vivo experiment also showed that the encapsulated oils at 1500 ppm concentration significantly decreased both disease severity and incidence of Botrytis-inoculated strawberries during 7 days of storage at 4 °C followed by 2–3 more days at 20 °C. These findings revealed the promising role of CSNPs as a controlled release system for EOs in order to enhance antifungal activities. Industrial relevance: Application of plant essential oil (EOs) treatment at pre- or postharvest stage has been considered as an alternative treatment to the use of synthetic fungicides to prevent fruit postharvest decay and to extend the storage life while retaining the overall quality of different fresh commodities. Although EOs have proved to be good antimicrobial agents, their use for maintaining fruit quality and reducing fungal decay is often limited due to their volatile compounds which can easily suffer degradation under the action of heat, pressure, light and oxygen. Furthermore, they are insoluble in water, and for certain applications a controlled release is required. In this regard, nano-size carriers provide more surface area and can possibly upgrade solubility, enhance bioavailability and improve controlled release and targeting of the encapsulated food ingredients, in comparison to micro-size carriers. These findings revealed the promising role of CSNPs as a controlled release system for EOs in order to enhance their antimicrobial activities.
90813618
Chitosan coatings enriched with essential oils: Effects on fungi involved in fruit decay and mechanisms of action
Abstract Background P esticides have a negative impact on the health of consumers and on the environment, and as a consequence, the use of naturally occurring antimicrobial agents have become more popular to prevent food spoilage. An alternative is the use of chitosan, because of its antimicrobial, antioxidant activities and its capacity to form films having good mechanical properties. Chitosan has been used in the preparation of films and coatings for the preservation of different food products, and the addition of essential oils have been shown to be a good strategy to improve its antimicrobial activity in situ. Scope and approach This review compiles information related to studies and research that employ chitosan as matrix for films, coatings and nanogels with essential oils extracted from plants, as antifungal agent. A special emphasis has been addressed to the effect exerted on the most pathogenic fungi for crops, also highlighting the mechanisms of action that researchers attribute to the composite, together with inhibition data. Key Findings and Conclusion Effective natural treatments, using chitosan-essential oils films or nano-emulsions, improve the preservation of fruit in terms of fungal decay. The effect is particularly dependent on the ability to release the antimicrobial compounds from the polymer matrix, the type of essential oils, the fungal species, and the incubation temperature. Several efforts are still required to understand in detail the mechanism of degradation of perishable food, how the chitosan-essential oils composites control or inhibit food decay, the effects on other pathogenic and non-pathogenic moulds as well as on the production of mycotoxins.
98370332
Effect of hydroxypropylmethylcellulose and chitosan coatings with and without bergamot essential oil on quality and safety of cold-stored grapes
Biodegradable coatings based on hydroxypropylmethylcellulose (HPMC) or chitosan (CH) with and without bergamot essential oil were applied to table grapes, cv. Muscatel, in order to find environmentally friendly, healthy treatments with which to better preserve fresh fruit quality and safety during postharvest cold storage. Physicochemical properties (weight loss, °Brix, total phenols, antioxidant activity, colour and texture), respiration rates and microbial counts of samples were determined throughout cold storage. The coatings had a significant effect on the development of quality variables, with the additional effect of essential oil addition as a function of the polysaccharide matrix being especially notable. Although incorporation of essential oil resulted in smaller weight losses and a greater antimicrobial effect, it also led to browner samples when using CH. Chitosan coatings containing bergamot oil were more effective than pure CH and HPMC coatings at inhibiting respiration rates. All the coatings improved the mechanical resistance of the samples at the end of storage. The most recommended coating for Muscatel table grapes is CH containing bergamot oil since, despite only contributing slightly to the sample colour, this showed the highest antimicrobial activity and the greatest control of respiration rates with a reasonably good control of water loss during storage.
3458010
Ruta graveolens water extract inhibits cell‐cell network formation in human umbilical endothelial cells via MEK‐ERK1/2 pathway
ABSTRACT Angiogenesis is a process encompassing several steps such as endothelial cells proliferation, differentiation and migration to form a vascular network, involving different signal transduction pathways. Among these, ERK1/2 signaling mediates VEGF‐dependent signaling pathway. Here we report that the water extract of Ruta graveolens (RGWE), widely known as a medicinal plant, is able to impair in a dose‐dependent manner, cell network formation without affecting cell viability. Biochemical analysis showed that the major component of RGWE is rutin, unable to reproduce RGWE effect. We found that RGWE inhibits ERK1/2 phosphorylation and that this event is crucial in cell network formation since the transfection of HUVEC with a constitutively active MEK (caMEK), the ERK1/2 activator, induces a robust cell network formation as compared to untransfected and/or mock transfected cells and, more importantly, caMEK transfected cells became unresponsive to RGWE. Moreover, RGWE inhibits VEGF and nestin gene expression, necessary for vessel formation, and the caMEK transfection induces their higher expression. In conclusion, we report that RGWE is able to significantly impair vessels network formation without affecting cell viability, preventing ERK1/2 activation and, in turn, down‐regulating VEGF and nestin expression. These findings point to RGWE as a potential therapeutic tool capable to interfere with pathologic angiogenesis. Graphical abstract RGWE inhibits MEK‐ERK1/2 phosphorylation in HUVEC. MEK‐ERK1/2 phosphorylation is a key point in the intracellular signaling pathway leading from VEGF receptor activation to angiogenesis and vasculogenesis and its inhibition may represent an interesting way to limit excessive blood vessels neoformation. Figure. No Caption available. HighlightsRGWE inhibits HUVEC ability to form tubes on matrigel in vitro.RGWE interferes, through MEK/ERK, with the VEGF‐mediated signaling that leads to angiogenesis.RGWE is proposed as a new therapeutic tool to prevent pathological angiogenesis.
84183298
Assessment of Total Phenolic Content, In Vitro Antioxidant and Antibacterial Activity of Ruta graveolens L. Extracts Obtained by Choline Chloride Based Natural Deep Eutectic Solvents
Rue (R. graveolens) has been an extensively studied medicinal plant due to its rich phytochemicals content, such as furanocoumarins and flavonoids. The aim of this study was to determine the effects of varying extraction conditions on the total phenolic content, the antioxidant and antibacterial property of rue leaves crude extracts using deep eutectic solvents with different water content. These extraction conditions include the temperature and the extraction time. The extract obtained at 30 °C, with 20% water and at 90 min, with 13.3 µg mL−1 concentration, was found to possess the highest total phenolic content (38.24 ± 0.11 mg of GAE g−1 of DM) and the highest antioxidant activity (72.53 ± 0.31%). In this study, the same extract showed the best antibacterial efficiency against all the tested strains, especially gram-negative P. aeruginosa.
51703736
Therapeutic management of peritoneal ascitic sarcomatosis by Ruta graveolens: A study in experimental mice.
RELEVANCE
Malignant peritoneal sarcomatosis related ascitic formation often leads to grave consequences but the therapeutic management of the fatal pathophysiological condition remains a rarely discussed issue. The present study investigates the anti-neoplastic activity of the plant alkaloid from Ruta graveolens on ascitic Sarcoma-180 bearing mice as a model of human malignant peritoneal ascites.


MATERIALS AND METHODS
The efficacy of the loco-regional administration of Ruta graveolens on tumour cells was explored with cytopathological and cytotoxicological studies, along with the expressional modulation vital regulatory molecules viz. Chk2, c-Myc, CD95 and Aurora kinase.


RESULTS
The study revealed a series of anti-neoplastic events exerted by Ruta graveolens that included the boosting of anti-tumour immunity, generation of tumour cell cytotoxicity and disruption of cellular energetics which lead to the induction of apoptosis and simultaneous impairment of cell division in tumour cells. Expressional decline of c-Myc oncoproteins and mitosis promoter Aurora kinase A together with up regulation of vital tumour suppressor Chk-2 and apoptosis inducer CD 95 in ascitic tumour cells was also found to be associated with Ruta administration.


CONCLUSION
Our observations revealed that loco-regional Ruta administration resulted in the anti-neoplastic effect on peritoneal sarcoma related ascites and the alteration of vital regulatory molecules which depicted the therapeutic utility of Ruta in the management of peritoneal malignant ascites.
29733719
Methanolic extract of Ruta graveolens L. inhibits inflammation and oxidative stress in adjuvant induced model of arthritis in rats
Abstract:Ruta graveolens L. (Rutaceae) are traditionally used for the treatment of rheumatism, arthritis and other inflammatory conditions in the traditional medicine of India. The purpose of this study was to investigate anti-inflammatory and anti-oxidant effects of methanolic extract of Ruta graveolens L. in adjuvant induced arthritis in rats. Methanolic extract of Ruta graveolens (MER) exhibited maximum percentage of oedema inhibition at a dose of 20 mg/kg on 21st day of adjuvant arthritis. The effect was higher than that of standard drug indomethacin. The activities of cycloxygenase-2 and myeloperoxidase and concentration of thiobarbituric acid reactive substance (TBARS) were decreased and the activities of antioxidant enzymes, vitamins C & E and reduced glutathione level were increased on treatment with MER. The increment in ESR and total WBC, reduction in RBC count and haemoglobin and aberrant changes to the C-reactive protein (CRP) and ceruloplasmin levels observed in the arthritic animals were also found to be significantly restored in MER treated rats. Histopathology of paw tissue showed decreased oedema formation and cellular infiltration on supplementation with MER. Thus the results demonstrated the potential beneficiary effect of methanolic extract of Ruta graveolens on adjuvant induced arthritis in rats.
41703523
Chemical composition, antibacterial and antifungal activities of Ruta graveolens L. volatile oils
Abstract The Ruta graveolens L. (Rutaceae) plant is used medicinally as a homeopathic remedy in various areas of the world. In this study, volatile oils were extracted from the areal parts of the plant which was collected from southern India, then investigated for its chemical constituents and antimicrobial activities. The volatile oils were extracted by hydrodistillation using a Clevenger apparatus and samples were simultaneously analyzed with GC and GC-MS. As a result, a total of 13 chemical constituents were characterized. Representing 100% of the total oil with 2-ketones are the major groups. The principal components were identified, undecanone-2 (43.66%), 2-nonanone (16.09%), 2-acetoxy tetradecanone (14.49%), and nonyl cyclopropanecarboxylate (9.22%), respectively. The extracted volatile oil showed antibacterial activity against gram-positive and gram-negative bacteria, resulting in a number of common human pathogenic bacteria including methicillin-resistant Staphylococcus aureus and the yeast Candida albicans. The zone of inhibition is from 12.57 ± 0.03 to 27.10 ± 0.02 mm. The minimum inhibitory concentration (MIC) values were within the antimicrobial activity range and varied between 0.70 ± 0.04 and 1.58 ± 0.05 μg/mL. The essential oil showed maximum antifungal activity (35.10 ± 0.02 mm) against Candida albicans. This study indicates that R. graveolens L. essential oils could be used as a natural medical application in antimicrobial and antifungal treatments.
32942085
In vitro anti-mycotic activity of some medicinal plants containing flavonoids.
Aqueous, ethanolic and petroleum ether extracts of Citrus sinensis L. (Osbeck), Euphrasia officinalis L., Glycyrrhiza glabra L., Matricaria recutita L., Rosa canina L. and Ruta graveolens L. have been studied. The antimycotic activity was evaluated "in vitro" on strains of Candida albicans isolated from clinical samples obtained in the course of acute vaginitis.
21874090
Antifungal activity of plant extracts against dermatophytes
The aqueous extracts (15 μg ml−1 medium) of 22 plants used in folkloric medicine in Palestine were investigated for their antifungal activity and minimum inhibitory concentrations (MICs) against nine isolates of Microsporum canis, Trichophyton mentagrophytes and Trichophyton violaceum. The extract of the different plant species reduced colony growth of the three dermatophytes by 36 to 100% compared with the control treatment. Antimycotic activity of the extract against the three dermatophytes varied significantly (P<0.05) between test plants. Extracts of Capparis spinosa and Juglans regia completely prevented growth of M. canis and T. violaceum. The most active extracts (90–100% inhibition) were those of Anagallis arvensis, C. spinosa, J. regia, Pistacia lentiscus and Ruta chalapensis against M. canis; Inula viscosa, J. regia and P. lentiscus against T. mentagrophytes; and Asphodelus luteus, A. arvensis, C. spinosa, Clematis cirrhosa, I. viscosa, J. regia, P. lentiscus, Plumbago europea, Ruscus aculeatus, Retema raetam and Salvia fruticosa against T. violaceum. The MICs of these most active plants ranged from 0.6 to 40 μg ml−1. The three dermatophytes differed significantly with regard to their susceptibility to plant extracts. Trichophyton violaceum was the most susceptible being completely inhibited by 50% of the extracts followed by M. canis and T. mentagrophytes which were completely inhibited by only 23 and 14% of the extracts, respectively.
35532137
Antimicrobial substances in callus cultures of Ruta graveolens.
Callus cultures of RUTA GRAVEOLENS form at least 17 antimicrobial substances, some of which were identified. It appeared that acridone alkaloids (rutacridone-epoxide, hydroxyrutacridone-epoxide) are the most active substances against bacteria as well as against fungi. In comparison with the medicinally used ethacridine lactate, rutacridone-epoxides proved to be much more active. Coumarins (rutarm, xanthotoxin, bergapten etc.) only cause any inhibition in higher concentrations. Furoquinoline alkaloids (dictamnine, γ-fagarine) are more active than the furocoumarins. Essential oil components and flavonoids do not show any antibiotic activity in our test.
29510878
Fungistatic Activity of Ruta graveolens Extract and Its Allelochemicals
The biological activity of an extract of Ruta graveolens and its allelochemicals [8-methoxypsoralen (8-MOP), 5-methoxypsoralen (5-MOP) and 4-hydroxycoumarin] (previously isolated) was evaluated gainst pathogenic fungi: Fusarium solani, Pyrenochaeta lycopersici, and Trichoderma viride. In addition a rue lyophilized extract was also tested against Penicillium sp., Thielaviopsis basicola, and Verticillium dahliae. We determined that 5 g rue lyophilized extract/liter, the lowest concentration tested, inhibited the mycelial growth of P. lycopersici and V. dahliae by 63.6% and 47%, respectively, with IC50 (the concentration required to inhibit growth 50%) values of 4.16 and 6.5 g/liter, respectively. Moreover, the rue lyophilized extract was shown to reduce radial growth of all six fungal species significantly at concentrations ranging from 5.0 to 40.0 g/liter. Mycelial growth of Penicillium sp. was promoted at 5.0 g lyophilized rue extract/liter and inhibited at higher concentrations. 4-OH coumarin had no effect on the growth of these fungi at concentrations ranging from 0.32 to 2.60 mg/liter, whereas 8-MOP and 5-MOP inhibited the mycelial growth of F. solani and T. viride with IC50 values of 6 mg/liter (5-MOP) and 27 mg/liter (8-MOP) for both fungi, respectively. A mixture of 5-MOP and 8-MOP, tested at 64.8 mg/liter (as they naturally occur in the crude rue extract) significantly inhibited the growth of all tested fungal species. These results suggest potential role for the rue extract and its allelochemicals in controlling pathogenic fungal infections.
98617136
Chitosan application for active bio-based films production and potential in the food industry: Review
During the past decade, there was an increasing interest to develop and use bio-based active films which are characterized by antimicrobial and antifungal activities in order to improve food preservation and to reduce the use of chemical preservatives. Biologically active bio-molecules such as chitosan and its derivatives have a significant potential in the food industry in view of contaminations associated with food products and the increasing concerns in relation with the negative environmental impact of conventional packaging materials such as plastics. Chitosan offers real potential for applications in the food industry due to its particular physico-chemical properties, short time biodegradability, biocompatibility with human tissues, antimicrobial an antifungal activities, and non-toxicity. Thus, chitosan-based films have attracted serious attention in food preservation and packaging technology. This is mainly due to a fact that chitosan exhibits high antimicrobial activity against pathogenic and spoilage micro-organisms, including fungi, and both Gram-positive and Gram-negative bacteria. The aim of the present review was to summarize the most important information on chitosan from its bioactivity point of view and to highlight various preparative methods used for chitosan-based active bio-films and their potential for applications in the food preservation and packaging technology.
24832163
Shelf life extension of fresh fruit and vegetables by chitosan treatment
ABSTRACT Among alternatives that are currently under investigation to replace the use of synthetic fungicides to control postharvest diseases in fresh produce and to extend their shelf life, chitosan application has shown promising disease control, at both preharvest and postharvest stages. Chitosan shows a dual mode of action, on the pathogen and on the plant, as it reduces the growth of decay-causing fungi and foodborne pathogens and induces resistance responses in the host tissues. Chitosan coating forms a semipermeable film on the surface of fruit and vegetables, thereby delaying the rate of respiration, decreasing weight loss, maintaining the overall quality, and prolonging the shelf life. Moreover, the coating can provide a substrate for incorporation of other functional food additives, such as minerals, vitamins, or other drugs or nutraceutical compounds that can be used to enhance the beneficial properties of fresh commodities, or in some cases the antimicrobial activity of chitosan. Chitosan coating has been approved as GRAS substance by USFDA, and its application is safe for the consumer and the environment. This review summarizes the most relevant and recent knowledge in the application of chitosan in postharvest disease control and maintenance of overall fruit and vegetable quality during postharvest storage.
97248770
Chitosan Coating Effect on Storability and Quality of Fresh Strawberries
The effect of chitosan coating (1.0 and 1.5% w/v) in controlling decay of strawberries at 13°C was investigated as compared to a fungicide, iprodione (Rovral®). Chitosan coating significantly reduced decay of berries (P ≤ 0.05) compared to the control. There was no significant difference between chitosan and fungicide treatments up to 21 days storage. Thereafter, Rovral®-treated berries decayed at a higher rate than chitosan-coated berries. Chitosan-coated berries stored at 4°C were firmer, higher in titratable acidity, and synthesized anthocyanin at a slower rate than Rovral®-treated or nontreated berries. Chitosan coating decreased respiration rate of the berries with a greater effect at higher concentration.
84873790
Effects of chitosan coating on postharvest life and quality of longan fruit
Abstract The effects of chitosan coating in extending postharvest life of longan fruits and maintaining their quality were investigated. The fruits were treated with aqueous solutions of 0.5, 1.0 and 2.0% chitosan, respectively, and then stored at 2°C and 90% relative humidity. Changes in respiration rate, polyphenol oxidase (PPO) activity, colour, eating quality, and weight loss were measured. The effect of chitosan coating on disease incidence was also evaluated. The application of chitosan coating reduced respiration rate and weight loss, delayed the increase in PPO activity and the changes in colour, and eating quality, and partially inhibited decay of fruit during storage. Furthermore, increasing the concentration of chitosan coating enhanced the beneficial effects of chitosan on postharvest life and quality of the fruit.
84661547
Effect of chitosan on incidence of brown rot, quality and physiological attributes of postharvest peach fruit
The effect of chitosan (5.0 and 10.0 mg ml −1) on the incidence of brown rot (caused by Monilinia fructicola), quality attributes and senescence physiology of peaches was investigated. It was found that both concentrations of chitosan reduced the incidence of brown rot significantly and delayed the development of disease compared with the control, but were less effective than the fungicide prochloraz. Chitosan-treated peaches were firmer and had higher titratable acidity and vitamin C content than prochloraz-treated or control peaches. Compared to control (water-treated) peaches, chitosan-treated peaches showed lower respiration rate, less ethylene and malondialdehyde (MDA) production, higher superoxide dismutase (SOD) activity and better membrane integrity. Hence it can be concluded that chitosan has the potential to control brown rot, preserve valuable attributes and prolong the shelf life of postharvest peaches, presumably because of its antifungal property and inhibition of the ripening and senescence process of postharvest peaches. 
 
© 2000 Society of Chemical Industry
95818216
Polysaccharide-based composite coating formulations for shelf-life extension of fresh banana and mango
The effects of four different composite coating formulations based on polysaccharides on maintaining quality and an extended shelf-life of banana and mango at 27±2 °C were investigated and compared with commercial Waxol-coated and uncoated fruits. The formulations consisted of modified starch, cellulose and chitosan, blended with a suitable lipid component and a wetting agent. Quality parameters measured included firmness, total soluble solids and titratable acidity. Physiological parameters measured were CO2 evolved and weight loss due to respiration and transpiration. The polysaccharide-based coatings displayed retarded colour development, lower acidity and greater firmness values compared to Waxol and control. CO2 evolution and loss in weight were also reduced significantly. The data were also subjected to PCA, to differentiate the characteristics of the five types of films. Chitosan-based coatings were much superior in prolonging the shelf-life and quality of banana and mango.
40964888
Synergistic mixtures of chitosan and Mentha piperita L. essential oil to inhibit Colletotrichum species and anthracnose development in mango cultivar Tommy Atkins.
This study assessed the efficacy of chitosan (CHI) and Mentha piperita L. essential oil (MPEO) alone or in combination to control the mycelial growth of five different Colletotrichum species, C. asianum, C. dianesei, C. fructicola, C. tropicale and C. karstii, identified as potential anthracnose-causing agents in mango (Mangifera indica L.). The efficacy of coatings of CHI and MPEO mixtures in controlling the development of anthracnose in mango cultivar Tommy Atkins was evaluated. CHI (2.5, 5, 7.5 and 10 mg/mL) and MPEO (0.3, 0.6, 1.25, 2.5 and 5 μL/mL) alone effectively inhibited mycelial growth of all tested Colletotrichum strains in synthetic media. Mixtures of CHI (5 or 7.5 mg/mL) and MPEO (0.3, 0.6 or 1.25 μL/mL) strongly inhibited mycelial growth and showed additive or synergistic inhibitory effects on the tested Colletotrichum strains based on the Abbott index. The application of coatings of CHI (5 or 7.5 mg/mL) and MPEO (0.6 or 1.25 μL/mL) mixtures that presented synergistic interactions decreased anthracnose lesion severity in mango artificially contaminated with either of the tested Colletotrichum strains over 15 days of storage at 25 °C. The anthracnose lesion severity in mango coated with the mixtures of CHI and MPEO was similar or lower than those observed in mango treated with the synthetic fungicides thiophanate-methyl (10 μg a.i./mL) and difenoconazole (0.5 μg a.i./mL). The application of coatings containing low doses of CHI and MPEO may be an effective alternative for controlling the postharvest development of anthracnose in mango cultivar Tommy Atkins.
56026343
The efficacy of combined application of edible coatings and thyme oil in inducing resistance components in avocado (Persea americana Mill.) against anthracnose during post-harvest storage
Abstract Avocado fruit has high economic value; however, major post-harvest losses are encountered throughout the supply chain mostly due to anthracnose disease caused by the fungus Colletotrichum gloeosporioides . Increasing consumer concern regarding food safety and demand for organically produced fruits makes it necessary to search for natural environmentally friendly alternative products and processes for the fruit industry; particularly in disease control. Antifungal effects of Gum Arabic (GA) (10%), Aloe vera (AL) (2%), chitosan (CH) (1%) alone or in combination with thyme oil (1%) were investigated in vitro. CH + thyme oil and AL + thyme oil [1:1 or 3:1 v/v] showed fungicidal effects while AL, CH, GA and GA + thyme oil [3:1 v/v] showed fungistatic effects on mycelial growth of C. gloeosporioides in vitro . CH and AL coatings alone or in combination with thyme oil [3:1 v/v], either as preventative or curative treatments in comparison with commercial treatment (prochloraz, 0.05%) and untreated control were evaluated on incidence and severity (lesion diameter) of anthracnose in vivo . Preventative CH + thyme oil treatments significantly reduced the severity of anthracnose (8.9 mm) compared to thyme oil (12.7 mm), AL + TO (14.4 mm), CH (17.8 mm), AL (20.6 mm), PZ (18.3 mm) and untreated samples (34.8 mm). As curative method, the CH + thyme oil combination also reduced the severity of anthracnose by at least 4 mm compared to the other treatments. The total phenols, polyphenol oxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, chitinase, catalase and superoxide dismutase activities, firmness and flesh colour were also determined. Results showed an increase in peroxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, chitinase, catalase and superoxide dismutase activities and total phenolics with reduced loss of firmness and flesh colour following CH + thyme oil treatments. This investigation recommends CH + thyme oil [3:1 v/v] combination treatment as a suitable alternative to the currently adopted prochloraz applications in controlling anthracnose disease in avocado fruit during storage.
90590064
The Effect of Nanostructured Chitosan and Chitosan‐thyme Essential Oil Coatings on Colletotrichum gloeosporioides Growth in vitro and on cv Hass Avocado and Fruit Quality
In this study, nanostructured edible coatings based on chitosan nanoparticles (CSNPs) and chitosan-thyme essential oil nanoparticles (CSTEO-NPs) were characterized and evaluated on in vitro growth of Colletotrichum gloeosporioides and on inoculated avocado fruit cv. Hass, to evaluate their fungicidal activity and the effect on fruit quality. From TEM and particle size distribution characterization, the size of nanoparticles increased after thyme essential oil incorporation. Overall a synergistic effect between the chitosan and thyme essential oil (TEO) was observed. For in vitro evaluation, incorporation of this essential oil to CSNPs improved the control of C. gloeosporioides as there was a complete growth inhibition. CSNPs with concentrations of TEO at 3 and 5% had a fungicidal effect. The coating formulation with 55% CSTEO-NPs notably reduced the incidence of C. gloeosporioides on avocado cv. Hass by up to 60%. Also, at the end of the 8-day storage period, CSTEO-NPs incorporation into the coating did not affect the quality of avocado; moreover, fruit firmness was better maintained than untreated fruit.
46462496
Chitosan based edible films and coatings: a review.
Chitosan is a biodegradable biocompatible polymer derived from natural renewable resources with numerous applications in various fields, and one of which is the area of edible films and coatings. Chitosan has antibacterial and antifungal properties which qualify it for food protection, however, its weak mechanical properties, gas and water vapor permeability limit its uses. This review discusses the application of chitosan and its blends with other natural polymers such as starch and other ingredients for example essential oils, and clay in the field of edible films for food protection. The mechanical behavior and the gas and water vapor permeability of the films are also discussed. References dealing with the antimicrobial behavior of these films and their impact on food protection are explored.
101885312
Sub-lethal concentrations of Colombian Austroeupatorium inulifolium (H.B.K.) essential oil and its effect on fungal growth and the production of enzymes
Abstract In this work, we studied the effects of Austroeupatorium inulifolium (H.B.K.) essential oil on the growth and the enzyme production of phyto-pathogens species such as Aspergillus spp., Penicillium spp. and Fusarium spp . “in vitro ”. Fungal growth was inhibited up to 70%, with P. brevicompactum and F. oxysporum being the most sensitive strains, while Aspergillus parasiticus and Penicillium nalgiovense were the most resistant. Sub-lethal concentrations of A. inulifolium essential oil increased pectinase, cellulase, protease and amylase activities in P. brevicompactum, A. flavus and F. oxysporum , with a concentration-dependent induction. Among the 71 compounds revealed by GC–MS analysis, trans β −caryophyllene and ledene oxide (II) were the most abundant molecules. The antioxidant potential was measured using four in vitro assays, revealing a good antioxidant activity. The obtained results suggested the importance of the assessment of enzyme production involved in plant wall cell degradation, when the antifungal activity is evaluated. In addition, the use of sub-lethal concentrations of A. inulifolium essential oil to increase enzymatic activities in fungi can have great potential in the field of bioprospecting and biotechnology.
86966415
Rheological methods in food process engineering
tiger has a tantrum a book about feeling angry (behaviour matters), car audio systems guide, edexcel mathematics a paper 1 non calculator thursday 28 february 2013 higher tier mark scheme, essay for life sciences march question paper grade 11 2014, seerat un nabi shibli nomani, by baltasar gracian a pocket mirror for heroes 1st first edition hardcover, arabic high school exam past paper, physics parts i and ii parts 1 2, mechanical engineering design projects final report, sega genesis price guide, arbeitsbuch to accompany kontakte 7th ed pdf, bouncers script pdf, effetti, potenzialità e limiti della globalizzazione, alberuni s india, solutions manual intermediate accounting 15th edition, scientific paper sample, doctor who: character encyclopedia, infinite self 33 steps to reclaiming your inner power pdf, kawasaki stx 12f 07 engine rebuild, rocketfish rf rbwhp01 user guide, teach like your hairs on fire the methods and madness inside room 56, the world of lore volume 1 monstrous creatures now a major online streaming series, comp exams counseling study guide, special problems in corrections, servel gas refrigerator service manual, one direction the official
56256962
Assessment of antioxidant and antibacterial potential of borojo fruit (Borojoa patinoi Cuatrecasas) from the rainforests of South America
Abstract Borojo (Borojoa patinoi) is an endemic fruit of the rainforests of Colombia, Brazil, Peru, Ecuador and Panama that is listed for approval as novel food in the European Union. In this work the antioxidant activity (measured with DPPH, FIC and FRAP), the organic acid and sugar contents, the volatile profile and the antibacterial properties against 26 pathogenic and non-pathogenic strains were studied. Total phenol contents (TPC) ranged from 36.41 to 53.6 mg GAE/100 g fw while total flavonoids (TFC) from 88.45 to 49.83 mg RE/100 g fw. The extract showed also good antioxidant activity highly correlated to TPC and TFC. Among 21 volatile compounds detected by SPME–GC–MS, 2-nonanol represented the main component. The antimicrobial activity was in a decreasing order: Salmonella enteritidis > Salmonella typhimurium > Listeria monocytogenes > Staphylococcus aureus > Brochotrix thermosphacta. The biological properties of Borojo-fruit suggested that it is a promising new antioxidant and antibacterial agent.
41403178
Chemical composition and antibacterial activities of the essential oils of Lippia chevalieri and Lippia multiflora from Burkina Faso.
The chemical composition of the essential oils of Lippia chevalieri and Lippia multiflora obtained from the air-dried leaves by hydrodistillation were analysed using GC and GC-MS. L. chevalieri and L. multiflora belonged to thymol/p-cymene/2-phenyl ethyl propionate and thymol/p-cymene/thymyl acetate chemotypes, respectively. The essential oils were also tested against 09 strains using a broth microdilution method. The Gram-negative bacteria were the most sensitive. The essential oil of L. multiflora was the most active.
98218467
Impact of plant essential oils on microbiological, organoleptic and quality markers of minimally processed vegetables
The objectives of this study were to evaluate the efficacy of plant essential oils (EOs) for control of the natural spoilage microflora on ready-to-eat (RTE) lettuce and carrots whilst also considering their impact on organoleptic properties. Initial decontamination effects achieved using EOs were comparable to that observed with chlorine and solution containing oregano recorded a significantly lower initial TVC level than the water treatment on carrots (p < 0.05). No significant differences were found between the EO treatments and chlorine considering gas composition, color, texture and water activity of samples. The sensory panel found EO treatments acceptable for carrots throughout storage, while lettuce washed with the EO solutions were rejected for overall appreciation by Day 7. Correlating microbial and sensory changes with volatile emissions identified 12 volatile quality markers. Oregano might be a suitable decontamination alternative to chlorine for RTE carrots, while the identification of volatile quality markers is a useful complement to sensory and microbiological assessments in the monitoring of organoleptic property changes and shelf-life of fresh vegetables. 
Industrial relevance 
There is industrial demand for natural alternatives to chlorine, which is commonly used for decontamination of fresh produce but which has limitations with respect to antimicrobial efficacy and possible formation of carcinogenic compounds in water. Plant essential oils have proven antimicrobial and other bioactive properties, however their usefulness in foods can be mitigated by their high sensory impact. This study examined the application of EOs for fresh produce decontamination addressing control of spoilage microflora and improving shelf-life characteristics whilst also considering the impact on organoleptic properties. The effectiveness of oregano as a decontamination treatment was comparable with that of chlorine. Carrot discs treated with the EO regimes were acceptable in terms of sensory quality and appreciation, therefore oregano could offer a natural alternative for the washing and preservation of fresh produce. Combining EOs with other natural preservatives might minimize doses and reduce the impact on organoleptic properties of fresh vegetables.
380240
Composition and Antimicrobial Activities of Lippia multiflora Moldenke, Mentha x piperita L. and Ocimum basilicum L. Essential Oils and Their Major Monoterpene Alcohols Alone and in Combination
Essential oils from leaves of Lippia multiflora, Mentha x piperita and Ocimum basilicum from Burkina Faso were analysed by GC–FID and GC–MS. Major components were p-cymene, thymol, β-caryophyllene, carvacrol and carvone for L. multiflora, menthol and iso-menthone for M. x piperita and, linalool and eugenol for O. basilicum. The essential oils and their major monoterpene alcohols were tested against nine bacterial strains using the disc diffusion and broth microdilution methods. The essential oils with high phenolic contents were the most effective antimicrobials. The checkerboard method was used to quantify the efficacy of paired combinations of essential oils and their major components. The best synergetic effects among essential oils and major components were obtained with combinations involving O. basilicum essential oil and eugenol, respectively. As phenolic components are characterized by a strong spicy aroma, this study suggests that the selection of certain combinations of EOs could help to reduce the amount of essential oils and consequently reduce any adverse sensory impact in food.
21862685
Bactericidal action of binary and ternary mixtures of carvacrol, thymol, and eugenol against Listeria innocua.
The bactericidal effect of 3 natural agents (carvacrol, thymol, and eugenol) was evaluated as well as their binary and ternary mixtures on Listeria innocua inactivation in liquid model systems. Minimal bactericidal concentrations (MBC) of these agents were determined, and then binary and ternary mixtures were evaluated. Culture media were inoculated with L. innocua and incubated for 72 h at 35 °C. Turbidity of studied systems were determined every 24 h. The most effective individual antimicrobial agent was carvacrol, followed by thymol and then eugenol with MBCs of 150, 250, and 450 mg kg(-1), respectively. It was observed that the most effective binary mixture was 75 mg kg(-1) carvacrol and 62.5 mg kg(-1) thymol. Furthermore, the ternary mixture carvacrol-thymol-eugenol in concentrations of 75, 31.25, and 56.25 mg kg(-1), correspondingly, was the most effective for L. innocua inactivation. Several binary and ternary mixtures of these 3 natural antimicrobial agents worked adequately to inactivate L. innocua.
83984761
Synergistic action between fractions of essential oils from Cymbopogon citratus, Ocimum gratissimum and Thymus vulgaris against Penicillium expansum
Penicillium expansum is a mould that causes the rotting of several fruits and vegetables, especially apples onto which it also synthesizes some dangerous mycotoxins. The degree of synergism between fractions of essential from Cymbopogon citratus, Ocimum gratissimum and Thymus vulgaris was evaluated against two mycotoxin producing strains of P. expansum. The antifungal activity determined by dilution method and expressed as a Number of Decimal Reduction of the colony forming units per ml (NDR cfu) showed that the essential oils extracted from O. gratissimum was significantly (P < 0.05) more active against P. expansum than those extracted from C. citratus and T. vulgaris. Fractions enriched with oxygenated terpenes were significantly (P < 0.05) more active than their respective essential oils, whereas most of the fractions enriched with terpene hydrocarbons, were significantly (P < 0.05) less active. The fungicidal activity of mixtures of fractions from the same essential oils or from two different essential oils showed that there exist synergistic, additive and antagonistic effects between fractions of the three essential oils tested against both fungal strains. The synergistic effects observed could be exploited in order to maximize the antimicrobial activity of essential oils and to minimize the concentrations of essential oil required to produce a given antimicrobial effect without any alteration of the food test.
83749948
Antibacterial mode of action of Cudrania tricuspidata fruit essential oil, affecting membrane permeability and surface characteristics of food-borne pathogens
Abstract The present investigation reports on the chemical composition of Cudrania tricuspidata fruit essential oil (CTEO) and examines its possible antimicrobial mode of action against food-borne pathogenic bacteria. The CTEO was obtained by hydrodistillation of C. tricuspidata fruits using a microwave-assisted extraction technique. Gas chromatography-mass spectrometry analysis of the CTEO resulted in the determination of 29 different compounds, representing 94.46% of the total oil. The CTEO (1000 μg/disc) showed potential antibacterial effect as diameters of inhibition zones (15.0 ± 0.1–21.0 ± 1.0 mm) against the tested food-borne pathogenic bacteria including Bacillus cereus ATCC 13061, Staphylococcus aureus ATCC 12600, Listeria monocytogenes ATCC 7644, Salmonella typhimurium ATCC 43174 and Escherichia coli O157:H7 ATCC 43889. The minimum inhibitory (MIC) and minimum bactericidal (MBC) concentration values of CTEO against the tested bacteria were found in the range of 250–1000 μg/mL, respectively. Also the CTEO had potential inhibitory effect on the cell viability of the tested pathogens at MIC concentration. The SEM analysis showed the inhibitory effect of CTEO as confirmed by considerable morphological alterations on the cell wall B. cereus ATCC 13061 and E. coli O157:H7 ATCC 43889. In addition, the CTEO revealed its mode of action on membrane integrity as confirmed by release of extracellular ATP, loss of 260-nm absorbing materials and leakage of potassium ions against food-borne pathogenic bacteria. These findings suggest that CTEO showed a broad-spectrum of antibacterial efficacy and compromise its mode of action on membrane integrity.
98037412
In vitro antimicrobial effects and mechanism of action of selected plant essential oil combinations against four food-related microorganisms
Abstract The aim of this study was to evaluate the antimicrobial efficacy of selected plant essential oil (EO) combinations against four food-related microorganisms. Ten EOs were initially screened against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Saccharomyces cerevisiae using agar disk diffusion and broth dilution methods. The highest efficacy against all the tested strains was shown when testing the oregano EO. EOs of basil and bergamot were active against the Gram-positive bacteria (S. aureus and B. subtilis), while perilla EO strongly inhibited the growth of yeast (S. cerevisiae). The chemical components of selected EOs were also analyzed by GC/MS. Phenols and terpenes were the major antimicrobial compounds in oregano and basil EOs. The dominant active components of bergamot EO were alcohols, esters and terpenes. For perilla EO, the major active constituents were mainly ketones. The checkerboard method was then used to investigate the antimicrobial efficacy of EO combinations by means of the fractional inhibitory concentration index (FICI). Based on an overall consideration of antimicrobial activity, organoleptic impact and cost, four EO combinations were selected and their MIC values were listed as follows: oregano–basil (0.313–0.313 μl/ml) for E. coli, basil–bergamot (0.313–0.156 μl/ml) for S. aureus, oregano–bergamot (0.313–0.313 μl/ml) for B. subtilis and oregano–perilla (0.313–0.156 μl/ml) for S. cerevisiae. Furthermore, the mechanisms of the antimicrobial action of EO combinations to the tested organisms were studied by the electronic microscopy observations of the cells and the measurement of the release of cell constituents. The electron micrographs of damaged cells and the significant increase of the cell constituents' release demonstrated that all EO combinations affected the cell membrane integrity.
30042089
Common Fragrance and Flavor Materials: Preparation, Properties and Uses
de Wet, J. M. J., K. E. P. Rap, M. H. Mengesha, and D. E. Brink. 1983. Domestication of sawa millet (Echinochloa colona). Econ. Bot. 37:283-291. Gould, F. W., M. A. All, and D. E. Fairbrothers. 1972. A revision of Echinochloa in the United States. Amer. Midl. Naturalist 87(1):36-59. Obara, T. 1936. On the nutritive value of Japanese barnyard millet. J. Agr. Chem. Soc. Japan 12: 1049-1058. (In Japanese.) 1938. Studien der Getreidfenniche. Proc. Crop Sci. Japan 9:471-518. Ohga, I. 1950. On the seeds found in the coffins. Pages 103-117 in Chusonji and the four generations of Fujiwara Family. Asahi Newspaper Office, Tokyo. Ohwi, J. 1962. On the Japanese species of the genus Echinochloa. Acta Phytotax. Geobot. 20:50-55. Okuda, M. 1957. Cool weather damage in Japan. Toyo-Keizai-Shinpo-Sha, Tokyo. (In Japanese.) Watanabe, N. 1970. A spodographic analysis of millet from prehistoric Japan. J. Fac. Sci. Univ. Tokyo, Sect. 5, 3:357-379. Yabuno, T. 1962. Cytotaxonomic studies on the two cultivated species and the wild relatives in the genus Echinochloa. Cytologia 27:296-305. 1966. Biosystematic study of the genus Echinochloa (Gramineae). Jap. J. Bot. 19:277-323. 1971. A note on barnyard millet. SABURAO Newsletter 3:43-45.
34021045
Biosynthesis of Plant Volatiles: Nature's Diversity and Ingenuity
Plant volatiles (PVs) are lipophilic molecules with high vapor pressure that serve various ecological roles. The synthesis of PVs involves the removal of hydrophilic moieties and oxidation/hydroxylation, reduction, methylation, and acylation reactions. Some PV biosynthetic enzymes produce multiple products from a single substrate or act on multiple substrates. Genes for PV biosynthesis evolve by duplication of genes that direct other aspects of plant metabolism; these duplicated genes then diverge from each other over time. Changes in the preferred substrate or resultant product of PV enzymes may occur through minimal changes of critical residues. Convergent evolution is often responsible for the ability of distally related species to synthesize the same volatile.
1982277
Antimicrobial Activity of Some Essential Oils—Present Status and Future Perspectives
Extensive documentation on the antimicrobial properties of essential oils and their constituents has been carried out by several workers. Although the mechanism of action of a few essential oil components has been elucidated in many pioneering works in the past, detailed knowledge of most of the compounds and their mechanism of action is still lacking. This knowledge is particularly important for the determination of the effect of essential oils on different microorganisms, how they work in combination with other antimicrobial compounds, and their interaction with food matrix components. Also, recent studies have demonstrated that nanoparticles (NPs) functionalized with essential oils have significant antimicrobial potential against multidrug- resistant pathogens due to an increase in chemical stability and solubility, decreased rapid evaporation and minimized degradation of active essential oil components. The application of encapsulated essential oils also supports their controlled and sustained release, which enhances their bioavailability and efficacy against multidrug-resistant pathogens. In the recent years, due to increasingly negative consumer perceptions of synthetic preservatives, interest in essential oils and their application in food preservation has been amplified. Moreover, the development of resistance to different antimicrobial agents by bacteria, fungi, viruses, parasites, etc. is a great challenge to the medical field for treating the infections caused by them, and hence, there is a pressing need to look for new and novel antimicrobials. To overcome these problems, nano-encapsulation of essential oils and exploiting the synergies between essential oils, constituents of essential oils, and antibiotics along with essential oils have been recommended as an answer to this problem. However, less is known about the interactions that lead to additive, synergistic, or antagonistic effects. A contributing role of this knowledge could be the design of new and more potent antimicrobial blends, and understanding of the interplay between the components of crude essential oils. This review is written with the purpose of giving an overview of current knowledge about the antimicrobial properties of essential oils and their mechanisms of action, components of essential oils, nano-encapsulated essential oils, and synergistic combinations of essential oils so as to find research areas that can facilitate applications of essential oils to overcome the problem of multidrug-resistant micro-organisms.
92615964
Encyclopedia of food sciences and nutrition
Topics include: Alcohol Antioxidants Body Composition Bread Cadmium Carbohydrates Cellulose Cheeses Chilled Storage Cholesterol Coffee Colors Computer Application Contamination Dairy Products Diabetes Drying Eating Habits Emulsifiers Enzymes Essential Oils Ethnic Foods Exercise Fat Substitutes Fatty Acids Fermented Foods Fish Flavor Compounds Food Additives Food Poisoning Food Labeling Food Production Food Safety Freezing Fruits Functional Foods Genetically Modified Foods Herbs Insect Pests Legislation Listeria Low-fat Foods Malnutrition Malt Meat Microscopy Milk Obesity Packaging Parasites Pasteurization Poultry Preservatives Protein Rice Sensory Evaluation Shellfish Soy Spoilage Starch Sugar Vegetable Oils Vegetarian Diets Vitamins Water Whey Wines Yoghurt ...and more!
20162325
Composition and antimicrobial activity of the essential oils of two Origanum species.
The essential oils obtained from the aerial parts of Origanum scabrum and Origaum microphyllum, both endemic species in Greece, were analyzed by means of GC and GC-MS. Forty-eight constituents were identified, representing 98.59 and 98.66% of the oils, respectively. Carvacrol, terpinen-4-ol, linalool, sabinene, alpha-terpinene, and gamma-terpinene were found as the major components. Furthermore, both samples exhibited a very interesting antimicrobial profile after they were tested against six Gram-negative and -positive bacteria and three pathogenic fungi.
84763744
Inhibitory effect of thyme and basil essential oils, carvacrol, thymol, estragol, linalool and p-cymene towards Shigella sonnei and S. flexneri
There are a few reports on the antimicrobial activity of essential oils or their major constituents towards Shigella sp. The antimicrobial effect of basil and thyme essential oil and its major constituents thymol, p-cymene, estragol, linalool, and carvacrol was determined using the agar well diffusion assay. Thyme essential oil and thymol and carvacrol showed inhibition of Shigella sp. in the agar well diffusion method. The potential of thyme essential oil, thymol and carvacrol at 0.5% and 1.0% v/v for decontamination of lettuce was evaluated. A decrease of the shigellae was observed after washing with 0.5% while at 1% Shigella numbers dropped below the detection limit. However, the antimicrobial effect on a subsequent lettuce sample in the same decontamination solution was significantly decreased. In addition, application of thyme essential oil or thymol or carvacrol for decontamination is hampered by sensoric properties of the lettuce (browning, strong odour).
21789470
Assessment of factors influencing antimicrobial activity of carvacrol and cymene against Vibrio cholerae in food.
Carvacrol and cymene, phenolic compounds naturally present in the essential oil of oregano and thyme, were examined for their antimicrobial activity against Vibrio cholerae (ATCC 14033, VC1, and VC7) inoculated in carrot juice. Carvacrol exhibited a dose dependent inhibitory effect on the bacteria. Although cymene did not have antimicrobial activity against the bacteria, it enhanced the inhibitory ability of carvacrol. At 25 °C, the lowest concentrations of carvacrol and cymene required for zero detectable viable count varied depending on bacterial strains; 5 and 5 ppm, respectively, for VC7; 5 and 7.5 ppm, respectively, for VC1; and 7.5 and 7.5 ppm, respectively, for ATCC 14033. This study also examined several factors influencing the antimicrobial activity of carvacrol and cymene against V. cholerae ATCC 14033, including temperature, bacterial cell number, and food substrate. Carvacrol and cymene inhibited the bacterium in carrot juice at 25 °C more efficiently than at 15 and 4 °C. The doses of both compounds required for zero detectable viable count increased as the number of the bacterial cells in the carrot juice increased. The fat content and the complexity of foods were shown to decrease the antimicrobial activity of the compounds.
38105314
The outer membrane of Pseudomonas aeruginosa NCTC 6749 contributes to its tolerance to the essential oil of Melaleuca alternifolia (tea tree oil)
Pseudomonas aeruginosa is less susceptible to the antimicrobial properties of tea tree oil than many bacteria and its tolerance is considered to be due to its outer membrane. Polymyxin B nonapeptide (PMBN), which has no antibacterial action, was used to permeabilize the outer membrane. The addition of PMBN to Ps. aeruginosa NCTC 6749 markedly increased this organism’s susceptibility to tea tree oil and to its normally inert hydrocarbons, p‐cymene and γ‐terpinene.
16480082
Carvacrol Induces Heat Shock Protein 60 and Inhibits Synthesis of Flagellin in Escherichia coli O157:H7
ABSTRACT The essential oils of oregano and thyme are active against a number of food-borne pathogens, such as Escherichia coli O157:H7. Carvacrol is one of the major antibacterial components of these oils, and p-cymene is thought to be its precursor in the plant. The effects of carvacrol and p-cymene on protein synthesis in E. coli O157:H7 ATCC 43895 cells were investigated. Bacteria were grown overnight in Mueller-Hinton broth with a sublethal concentration of carvacrol or p-cymene, and their protein compositions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and confirmed by Western blotting. The presence of 1 mM carvacrol during overnight incubation caused E. coli O157:H7 to produce significant amounts of heat shock protein 60 (HSP60) (GroEL) (P < 0.05) and inhibited the synthesis of flagellin highly significantly (P < 0.001), causing cells to be aflagellate and therefore nonmotile. The amounts of HSP70 (DnaK) were not significantly affected. p-Cymene at 1 mM or 10 mM did not induce HSP60 or HSP70 in significant amounts and did not have a significant effect on flagellar synthesis. Neither carvacrol (0.3, 0.5, 0.8, or 1 mM) nor p-cymene (0.3, 0.5, or 0.8 mM) treatment of cells in the mid-exponential growth phase induced significant amounts of HSP60 or HSP70 within 3 h, although numerical increases of HSP60 were observed. Motility decreased with increasing concentrations of both compounds, but existing flagella were not shed. This study is the first to demonstrate that essential oil components induce HSP60 in bacteria and that overnight incubation with carvacrol prevents the development of flagella in E. coli O157:H7.
97315200
Antifungal activity of selected essential oils against fungi isolated from medicinal plant
The development of protective products with natural origin as alternatives to synthetic fungicides is currently in the spotlight. Qualitative and quantitative chemical analysis of 16 selected essential oils was determined. Then, antifungal properties determined by in vitro microdilution method against 21 fungi isolated from herbal drugs were evaluated. All tested oils showed some antifungal activity against all fungi used. Savory, thyme and oregano oils, characterized by the presence of phenol such as carvacrol and thymol, and rose oil containing mainly monoterpene alcohols (citronellol and geraniol) proved to be the most effective inhibitor of all fungi tested. Also, combination of particular oils showed reduction of the MIC values when combined, commendatory mixtures for potential application in practice. Moreover, the reduction of the total number of fungi, in situ, using selected essential oils was determined.
84656396
Active label-based packaging to extend the shelf-life of “Calanda” peach fruit: Changes in fruit quality and enzymatic activity
Abstract A new active packaging, consisting of a label with cinnamon essential oil incorporated and attached to plastic packaging, was used to extend the shelf-life of late-maturing peach fruit. After 12 days of storage at room temperature, the percentage of infected fruit in the active label packaging was 13% vs. 86% in the non-active packaging. Significant differences were obtained for weight loss (3.4% less at 12 days of storage) and firmness (more than 15.9 N at 12 days) during storage. The influence of the active packaging on the in vivo activity of lipoxygenase (LOX), polyphenol oxidase (PPO), peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), and of malondialdehyde (MDA) content as an indicator of lipid oxidation, was studied. The active agent, cinnamon essential oil, also reduced in vitro activity of LOX. Sensory analysis of the peaches was performed over the storage time. Most of positive descriptors were not significantly different from the optimum quality level (day 0) for peaches stored in the active package after 12 days at room temperature.
136642448
Biopolymers in Food Emulsions
Publisher Summary Biopolymers are widely used as emulsifiers in the food industry to improve the stability and physicochemical properties of food emulsions. This chapter aims to describe the formation, stability, and properties of food emulsions and consider the application of biopolymers as functional ingredients in emulsion-based foods. The electrical characteristics of the droplets in an emulsion-based food product may play an important role in determining their properties and shelf life. The overall properties of an emulsion-based food product depend on the type and concentration of ingredients that it contains as well as the processing operations used to manufacture it. The industrial production of a food emulsion usually involves a number of consecutive steps, which depend on the nature of the starting materials and the desired properties of the end product. These processes can be divided into pre-homogenization, homogenization, and post-homogenization steps. Emulsifiers used in the food industry vary greatly in their ability to form and stabilize emulsions and it is important for food manufacturers to identify the most appropriate emulsifier for each application. Food scientists use rheological measurements as an analytical tool to provide fundamental information about the structural organization and interactions of the components within emulsions.
55473835
Use of Essential Oils in Bioactive Edible Coatings: A Review
Antimicrobial and antioxidant properties of essential oils have previously been extensively reviewed. The mechanisms of action of essential oils have not been clearly identified but they seem to be related with their hydrophobic nature. Applying these natural compounds in the food industry could be a potential alternative, but its application costs and other problems, such as their intense aroma and potential toxicity, limit their use in the area of food preservation. An interesting strategy to reduce doses of essential oils while maintaining their effectiveness could be the incorporation of these natural compounds into edible/biodegradable films. This review discusses the use of essential oils as natural antimicrobial and antioxidant compounds to obtain bioactive films or coatings. The advantages and limitations are also reviewed.
93097191
Volatile and non-volatile chemical composition of the white guava fruit (Psidium guajava) at different stages of maturity
Abstract The effect of the maturation stages on the chemical composition and volatile compounds of the white Guava ( Psidium guajava ) Cv. Cortibel was investigated during three different stages. The stages were characterized by evolution of color, pH, titratable acidity, sugars, soluble solids, vitamin C and volatile components. The fruits were stored at 24 °C and air humidity of 74% for 13 days. The volatile extracts were obtained using headspace technique and analyzed using gas chromatograph/mass spectrometry (GC/MS) system. The titratable acidity and sugars decreased. The pH level and amount of vitamin C increased throughout progress of maturation. The behavior of volatile compounds of fruits in the three stages of maturation was: in immature fruits and those in their intermediate stage of maturation, were predominantly the aldehydes such as ( E )-2-hexenal and ( Z )-3-hexenal. In mature fruits, esters like Z -3-hexenyl acetate and E -3-hexenyl acetate and sesquiterpenes caryophyllene, α-humulene and β-bisabollene are present.
13743916
Putting primary metabolism into perspective to obtain better fruits
Background
One of the key goals of fruit biology is to understand the factors that influence fruit growth and quality, ultimately with a view to manipulating them for improvement of fruit traits.


Scope
Primary metabolism, which is not only essential for growth but is also a major component of fruit quality, is an obvious target for improvement. However, metabolism is a moving target that undergoes marked changes throughout fruit growth and ripening.


Conclusions
Agricultural practice and breeding have successfully improved fruit metabolic traits, but both face the complexity of the interplay between development, metabolism and the environment. Thus, more fundamental knowledge is needed to identify further strategies for the manipulation of fruit metabolism. Nearly two decades of post-genomics approaches involving transcriptomics, proteomics and/or metabolomics have generated a lot of information about the behaviour of fruit metabolic networks. Today, the emergence of modelling tools is providing the opportunity to turn this information into a mechanistic understanding of fruits, and ultimately to design better fruits. Since high-quality data are a key requirement in modelling, a range of must-have parameters and variables is proposed.
26605316
'Movers and shakers' in the regulation of fruit ripening: a cross-dissection of climacteric versus non-climacteric fruit.
Fruit ripening is a complex and highly coordinated developmental process involving the expression of many ripening-related genes under the control of a network of signalling pathways. The hormonal control of climacteric fruit ripening, especially ethylene perception and signalling transduction in tomato has been well characterized. Additionally, great strides have been made in understanding some of the major regulatory switches (transcription factors such as RIPENING-INHIBITOR and other transcriptional regulators such as COLOURLESS NON-RIPENING, TOMATO AGAMOUS-LIKE1 and ETHYLENE RESPONSE FACTORs), that are involved in tomato fruit ripening. In contrast, the regulatory network related to non-climacteric fruit ripening remains poorly understood. However, some of the most recent breakthrough research data have provided several lines of evidences for abscisic acid- and sucrose-mediated ripening of strawberry, a non-climacteric fruit model. In this review, we discuss the most recent research findings concerning the hormonal regulation of fleshy fruit ripening and their cross-talk and the future challenges taking tomato as a climacteric fruit model and strawberry as a non-climacteric fruit model. We also highlight the possible contribution of epigenetic changes including the role of plant microRNAs, which is opening new avenues and great possibilities in the fields of fruit-ripening research and postharvest biology.
53873682
Modifications in Organic Acid Profiles During Fruit Development and Ripening: Correlation or Causation?
The pivotal role of phytohormones during fruit development and ripening is considered established knowledge in plant biology. Perhaps less well-known is the growing body of evidence suggesting that organic acids play a key function in plant development and, in particular, in fruit development, maturation and ripening. Here, we critically review the connection between organic acids and the development of both climacteric and non-climacteric fruits. By analyzing the metabolic content of different fruits during their ontogenetic trajectory, we noticed that the content of organic acids in the early stages of fruit development is directly related to the supply of substrates for respiratory processes. Although different organic acid species can be found during fruit development in general, it appears that citrate and malate play major roles in this process, as they accumulate on a broad range of climacteric and non-climacteric fruits. We further highlight the functional significance of changes in organic acid profile in fruits due to either the manipulation of fruit-specific genes or the use of fruit-specific promoters. Despite the complexity behind the fluctuation in organic acid content during fruit development and ripening, we extend our understanding on the importance of organic acids on fruit metabolism and the need to further boost future research. We suggest that engineering organic acid metabolism could improve both qualitative and quantitative traits of crop fruits.
62004
Chitosan delays ripening and ROS production in guava (Psidium guajava L.) fruit.
Guava is a typically tropical fruit highly perishable with a short shelf-life due to intense metabolic activity after harvested. In attempt to minimize the problems related to the postharvest, we evaluated the physiochemical characteristics and antioxidant system in guava fruits under chitosan coating at concentrations of 1%, 2%, and 3% stored at 25°C during 96h. The chitosan suppressed the respiratory rate, fresh weight loss, firmness and skin color with delay in the degradation of chlorophyll. In the treatment with 2% and 3% of chitosan in the solid soluble content and ascorbic acid were reduced; retarded the loss of titratable acidity during 96h after treatment. These treatment induced significant decreases in the phenylalanine ammonia-lyase activity and significantly increases of peroxidase Activity. Our results suggest that chitosan effectively prolongs the quality attributes in guava fruits after harvesting due to increases in the antioxidant processes, delaying the ripening during room temperature of storage.
96740090
Effects of chitosan coating on quality and shelf life of peeled litchi fruit
Abstract Litchi pulp is very perishable and thus has a short shelf life, with marketers and consumers alike desiring a longer period. The current study was conducted to investigate the effects of chitosan coating on quality maintenance and shelf life extension of peeled fruit of cv. Huaizhi. Manually peeled litchi fruits were treated with aqueous solutions of 0%, 1%, 2% or 3% of chitosan, placed into trays over-wrapped with plastic film, and then stored at −1 °C. Changes in sensory quality in terms of taste and colour scales and weight loss were evaluated. Polyphenol oxidase (PPO) and peroxidase (POD) activities were also measured. Application of chitosan coating retarded weight loss and the decline in sensory quality, with higher contents of total soluble solids, titratable acid, and ascorbic acid, and suppressed the increase in activities of PPO and POD. The results showed that application of chitosan coating effectively maintained quality attributes and extended shelf life of the peeled fruit.
97752584
Effect of chitosan–lemon essential oil coatings on storage-keeping quality of strawberry
Abstract Film-forming dispersions (FFD) were prepared with 1% high molecular weight chitosan and 3% lemon essential oil and were submitted to two different homogenization treatments. The particle size and viscosity of the FFD were evaluated and stand-alone coatings were characterized in terms of water vapour permeability (WVP) and antimicrobial activity. The FFD were applied to cold-stored strawberries, cv. Camarosa, and the physicochemical properties, fungal decay and respiration rate of strawberries were determined throughout cold storage at 5 °C. The use of microfluidization to prepare chitosan-based FFD led to a significant reduction in the particle size and apparent viscosity of the dispersions, with no significant effect on the decrease in the WVP of the stand-alone coatings. Chitosan coatings did not show a significant effect in terms of the acidity, pH and soluble solid content of strawberries throughout storage. In contrast, coatings slowed down the respiration rate of samples when lemon essential oil was added to the FFD. Adding lemon essential oil enhanced the chitosan antifungal activity both in in vitro tests and during cold storage in strawberries inoculated with a spore suspension of Botrytis cinerea.
138795282
Effect of modified atmosphere on the storage life and quality of Eksotika papaya
Storage in modified atmosphere at 10 °C extended the storage life of Eksotika papaya. The packaging technique and composition of gases in the storage environment played important roles during storage. Bulk packaging (9–10 fruit/ pack) containing CO 2 and O 2 at 5% and 4% respectively helped to extend the storage life up to 3–4 weeks. The storage life was extended to about 5–6 weeks when the fruit were wrapped individually with gas composition in the environment containing 4% CO 2 and 8% O 2 . The use of ethylene absorbent during storage was also effective in reducing the ethylene gas content and thus the ripening process was retarded. With these conditions, the freshness of the fruit was maintained during storage without significant changes in the skin colour and fruit quality. Fruit ripened normally within 3–4 days when transferred to ambient temperature. The skin changed to yellow, and the pulp quality was still good and acceptable.
51698651
Response of pomegranate arils (cv. Wonderful) to low oxygen stress under active modified atmosphere condition.
BACKGROUND
Successful characterization of the relationship between respiration rate (RR) and low oxygen (O2 ) limit is critical for optimizing the modified atmosphere condition. It is well documented that a low O2 atmosphere reduces the RR of fresh produce, but could also lead to abiotic stress due to the accumulation of glycolysis end products. Therefore, this study investigated the response of pomegranate arils exposed to low O2 atmosphere (composed of 2 kPa O2 , 18 kPa carbon dioxide, and 80 kPa nitrogen) and identified the low O2 limit at 5 °C and 10 °C. The study aim was achieved by using real-time RR and respiration quotient (RQ) data, microbial growth, identifying changes in the fermentative volatile organic compounds profile, and the consumption of respiratory metabolites (organic acids and individual sugars).


RESULTS
The gas concentrations changed significantly respective to the storage temperature and resulted in a significant change in the parameters studied. The response of pomegranate arils to low O2 stress involves making alterations to the metabolic composition, especially those involved in anaerobiosis, such as the accumulation of ethanol, and an immediate increase on RQ.


CONCLUSION
Pomegranate arils (cv. Wonderful) can tolerate down to 1.9 kPa O2 and 2.3 kPa O2 concentrations at 5 °C and 10 °C respectively. © 2018 Society of Chemical Industry.
23236745
Effect of chitosan and alginate based coatings enriched with pomegranate peel extract to extend the postharvest quality of guava (Psidium guajava L.).
The influence of chitosan (1% w/v) and alginate (2% w/v) coatings in combination with pomegranate peel extract (PPE; 1% w/v) on quality of guavas (cv Allahabad safeda) were studied. Restricted changes were recorded in respiration rate, ripening index, and instrumental colour values in case of the coated samples as compared to the control for 20days at 10°C. Samples coated with chitosan enriched with PPE (CHE) proved to be the most effective treatment in maintaining the overall fruit quality. Ascorbic acid, total phenolics, total flavonoids contents and antioxidant activity were recorded with restricted losses of 29%, 8%, 12%, 12% (DPPH) and 9% (FRAP), respectively for CHE samples at the end of storage. A higher degree of correlation (r>0.918) was established between various phytochemicals and AOA. PPE enriched coatings was proved efficient in maintaining the quality of guavas during 20days of low temperature storage.
11653416
Impact of edible chitosan-cassava starch coatings enriched with Lippia gracilis Schauer genotype mixtures on the shelf life of guavas (Psidium guajava L.) during storage at room temperature.
The effect of edible chitosan-cassava starch (CH-CS) coatings containing a mixture of Lippia gracilis Schauer genotypes (EOM) on the shelf life of guavas during storage at room temperature for 10 days was studied. Sixteen formulations were prepared with a range of chitosan and essential oil mixtures concentrations, and the in vitro antimicrobial activity was tested. Formulations containing 2.0% cassava starch, 2.0% chitosan and 1.0%, 2.0% or 3.0% EOM were most effective in inhibiting the growth of the majority of bacteria. The edible CH-CS coating and CH-CS with 1.0% (CH-CS-EOM1) or 3.0% EOM (CH-CS-EOM3) were added to guavas and the shelf life was evaluated. On the tenth day of storage, total aerobic mesophilic bacteria and mould and yeast counts were statistically lower (p<0.05) in the CH-CS-EOM1- or CH-CS-EOM3-coated fruits than CH-CS-coated fruits. In addition, fruits coated with CH-CS or CH-CS-EOM showed no significant changes of total soluble solids content, while CH-CS-EOM-coated fruits showed lower titratable acidity than CH-CS-coated fruits at the end of storage. CH-CS-EOM3-coated guavas showed lower a(∗) and b(∗) values and higher L(∗) and hue values than those with other coatings.
205692928
Recent advances in modified atmosphere packaging and edible coatings to maintain quality of fresh-cut fruits and vegetables
ABSTRACT Processing of fruits and vegetables generates physiological stresses in the still living cut tissue, leading to quality deterioration and shorter shelf life as compared with fresh intact produces. Several strategies can be implemented with the aim to reduce the rate of deterioration of fresh-cut commodities. Such strategies include low temperature maintenance from harvest to retail and the application of physical and chemical treatments such as modified atmosphere packaging (MAP) with low O2 and high CO2 levels and antioxidant dips. Other technologies such as edible coatings with natural additives, new generation of coatings using nanotechnological solutions such as nanoparticles, nanoencapsulation, and multilayered systems, and nonconventional atmospheres such as the use of pressurized inert/noble gases and high levels of O2 have gained a lot of interest as a possibility to extend the shelf life of minimally processed fruits and vegetables. However, the high perishability of these products challenges in many cases their marketability by not achieving sufficient shelf life to survive the distribution system, requiring the combination of treatments to assure safety and quality. This review reports the recent advances in the use of MAP, edible coatings, and the combined effect of both technologies to extend the shelf life of fresh-cut fruits and vegetables.
106936507
Application of modified atmosphere packaging as a safety approach to fresh-cut fruits and vegetables – A review
This review provides an overview of the effect of modified atmosphere packaging (MAP) on the survival and growth of foodborne pathogens on fresh-cut fruits and vegetables. Substantial technological advances have been made in this area, mainly in improving the quality and shelf-life of minimally processed products. Nevertheless, attention must be paid on the survival and growth of pathogenic microorganisms that may be present in fruits and vegetables. Modified atmosphere packaging (MAP) in combination with refrigeration temperatures could be used as a mild preservation technique for safety of minimally processed fruits and vegetables. However, the effect of MAP on microorganisms can vary, depending mainly on the storage conditions and the type of packaged product.
94212032
Effect of active modified atmosphere and cold storage on the postharvest quality of cherry tomatoes
Abstract The effects of active modified atmosphere packaging (MAP) on the postharvest quality of cherry tomatoes stored at cold temperature (5 °C) and in bi-oriented polypropylene/low density polyethylene BOPP/LDPE bags were investigated. The atmosphere composition used in the packaging was 5% O2 + 5% CO2 (MAP), and synthetic air (control). The variables measured were weight loss, firmness, sugar, organic acids, color, lycopene, respiration rate, and ethylene biosynthesis over 25 days. The results showed that active MAP could extend the shelf life of cherry tomatoes to 25 days and the gas concentration could influence the postharvest quality of cherry tomatoes. MAP treatment decreased the respiration rate and ethylene production rate while reducing weight loss, lycopene biosynthesis, and the formation of red color. Through the use of MAP it was possible to maintain firmness and delay changes in sugar and organic acid contents. The combination of active MAP and low temperature treatments was effective with regard to delaying maturity during the storage period, and preserving the quality of cherry tomatoes.
24684594
Effects of ascorbic acid and high oxygen modified atmosphere packaging during storage of fresh-cut eggplants
Ascorbic acid dip and high O2 modified atmosphere packaging were used to alleviate browning and quality loss of fresh-cut eggplants. Fresh-cut eggplants were dipped in water or 0.5% ascorbic acid solution for 2 min before being packed in polyethylene film bags filled with air or high O2. The physiochemical and sensorial attributes of cut eggplants were evaluated during 12 days for storage at 4 ℃. Results demonstrated that high O2 modified atmosphere packaging and ascorbic acid dip improved the preservation of fresh-cut eggplants compared with the control. High O2 showed an ability to reduce the browning and inhibit polyphenol oxidase and peroxidase activities. Higher total phenolic content and lower malondialdehyde content were also observed in ascorbic acid treated samples during storage. Moreover, the combination of ascorbic acid and high O2 was more effective than single treatments. The surface color was protected by ascorbic acid and high O2 packaging, and higher sensory scores were observed after 12 days of storage.
93541517
Quality of guava (Psidium guajava L. cv. Pedro Sato) fruit stored in low-O2 controlled atmospheres is negatively affected by increasing levels of CO2
Abstract Guava is a climacteric fruit, extremely perishable, that has a short shelf life. Controlled atmosphere (CA) and cold storage can be used to extend guava shelf life. However, few studies have been conducted to evaluate the effects of CA storage on guavas, especially with high levels of carbon dioxide (CO 2 ). Therefore the objective of this study was to evaluate the quality changes of ‘Pedro Sato’ guava fruit during CA storage with atmospheres containing low concentrations of O 2 and increasing levels of CO 2 . For that, ‘Pedro Santo’ guavas were stored at 12.2 °C for up to 28 days in atmospheres with low oxygen (O 2 ) concentration (5 kPa) and increasing level of CO 2 (1, 5, 10, 15 or 20 kPa CO 2 ) in order to evaluate the fruit quality changes. It was possible to identify the relationships among quality variables in response to atmosphere composition and storage duration which were related to modifications due to ripening (ratio SS/TA, TSS, RS, TA), ripening and early CO 2 injury modifications (pH, SS, chromaticity), and CO 2 injury modifications (hue angle, firmness, soluble pectin). A clear CO 2 injury occurred in fruit stored in 5 kPa O 2  + 15 kPa CO 2 and 5 kPa O 2  + 20 kPa CO 2 after 28 days at 12.2 °C, with increasing pH values and soluble pectin content, which were inversely related to fruit firmness. ‘Pedro Sato’ guavas should be stored in atmospheres with 5 kPa O 2 and no more than 5 kPa CO 2 in order to prevent CO 2 damage. Further investigation is necessary to identify the metabolites responsible for the onset of responses to high CO 2 in guava fruit.
84495482
Effect of Nanochitosan-Based Coating With and Without Copper Loaded on Physicochemical and Bioactive Components of Fresh Strawberry Fruit (Fragaria x ananassa Duchesne) During Storage
Edible coatings based on nanochitosan (50–110 nm) with and without copper loaded were evaluated on physicochemical and bioactive components of strawberry. Fresh fruits were coated with copper-free and copper-loaded nanochitosans and stored at 4 ± 1 °C with 70 % relative humidity for 20 days. Both nanochitosan coatings provided an effective control in reducing weight loss and firmness as well as delayed changes in the respiration rate during 3 weeks. The antioxidant activity declined throughout the storage period of strawberries, although the decrease in antioxidant activity showed a slower rate in the strawberries coated with copper-free nanochitosan followed by copper-loaded nanochitosan compared with the control. Anthocyanin concentrations increased in fruits coated with copper free as well as copper-loaded nonochitosan at the first 12 days of storage followed by reduction in slow rates. However, no increase of anthocyanin was recorded for uncoated samples. Intensive reduction was recorded in ascorbic acid content of strawberries coated with copper-loaded nanochitosan, while the minimum loss of the ascorbic acid content was related to the copper-free nanochitosan. Also, both nanochitosans showed a significant suppression on the polyphenol oxidase and peroxidase activity, whereas a high rate of increase was recorded in control strawberry. The nanochitosan coatings with or without copper loaded significantly suppressed the visual loss and fungal decay of the strawberries during the storage compared with the control. The sensory evaluation of coated strawberries revealed that no effect on the consumer acceptability was detected as well as that copper-free nanochitosan showed better results in the point of preserving the overall flavor and appearance compared with the copper-loaded one.
44424127
Effects of chitosan-glucose complex coating on postharvest quality and shelf life of table grapes.
Surface coatings and films are prospective alternatives for extending the postharvest life of fresh fruits and vegetables. In this study, freshly harvested grapes were treated with chitosan, glucose, chitosan-glucose complex (CGC), or water (control) for up to 60 days at 0 °C in 95% relative humidity followed by 3 days in the air at 20 °C. The results showed that coated samples were effective in terms of senescence inhibition and postharvest diseases prevention. Chitosan-glucose complex showed better effects on delaying the declines of total soluble solids, ascorbic acid and titratable acidity, decreasing decay and weight loss, suppressing respiration rate, inducing POD and SOD activities, in comparison with pure chitosan or glucose. In addition, CGC coating treatment ensured better berry texture and higher sensory scores, compared with those treated with chitosan or glucose alone. The results indicated that CGC may be a promising strategy for improving the postharvest quality and extending the shelf life of table grapes.
84531483
Physiological responses and quality attributes of 'Kyoho' grapes to controlled atmosphere storage
Abstract This research studied the physiological responses and quality attributes of Kyoho grapes ( Vitis vinifera X V. labrusca ) to controlled atmosphere storage. The grapes were stored for up to 60 days in 95% relative humidity with four different conditions, 4% O 2 +9% CO 2 , 4% O 2 +30% CO 2 , 80% O 2, and air, as control. The examined physiological responses and quality attributes included polyphenol oxidase (PPO) activity, ethanol concentration, fruit detachment force (FDF), firmness, color, soluble solid content (SSC), titratable acidity (TA), ascorbic acid concentration (Vc), and sensory quality. PPO activity, FDF drop and decay incidence when stored in 4% O 2 +30% CO 2 were more effectively controlled, but unacceptable alcoholic flavor and browning were detected after 45 days, compared with those stored in 4% O 2 +9% CO 2 or 80% O 2 . The fruits kept in 4% O 2 +9% CO 2 or 80% O 2 had good quality during 60 days of storage. The results suggested that high O 2 atmosphere exhibited a potential for maintaining the quality of ‘Kyoho’ grapes during long-term storage.
102061136
The effects of composite coatings containing chitosan and Mentha (piperita L. or x villosa Huds) essential oil on postharvest mold occurrence and quality of table grape cv. Isabella
•Coatings comprising chitosan and Mentha spp. essential oil inhibited mold occurrence.•Test coatings delayed the appearance of postharvest mold infection in table grapes.•Test coatings did not negatively affect the quality of table grapes.
25208712
Chitosan films and coatings containing essential oils: The antioxidant and antimicrobial activity, and application in food systems.
Chitosan edible films and coatings have shown great promise for their application in food preservation and also are promising systems to be used as essential oil (EO) carriers. This review reports the most recent and relevant studies concerning chitosan films and coatings containing EOs. The effect of EO incorporation on the antioxidant, antibacterial and antifungal activities of chitosan films and coatings in vitro and in vivo, as well as their applications in food systems have been discussed. In general, incorporation of EOs significantly increased the antioxidant, antibacterial and antifungal efficacy of chitosan films and coatings in vitro. EO-incorporated films and coatings also showed greater effectiveness against postharvest fungi and foodborne bacteria in food systems than pure films and coatings. The application of chitosan films and coatings containing EOs usually led to an extension of the shelf-life and reduction of lipid peroxidation of fish and meat products over pure chitosan films and coatings. In addition, chitosan coatings incorporated with EOs were more effective in maintaining fruit and vegetable quality, and controlling their postharvest decay during storage and shelf life than pure chitosan coatings.
85076929
Physiological responses and quality attributes of table grape fruit to chitosan preharvest spray and postharvest coating during storage
The effects of preharvest chitosan spray (PCS) or/and postharvest chitosan coating (PCC) treatments on the quality and physiological response of table grape fruit stored at 20 or 0 °C was evaluated, respectively. PCS/PCC treatment showed the best control effect on decay. PCC or PCS/PCC treatment significantly decreased the weight loss of fruit stored at 20 °C. Additionally, all chitosan treatments inhibited the increase in rate of soluble solid content to titratable acid in fruit, stored at 20 °C, while enhancing the rate at 0 °C and affecting the content of total phenolic compounds in the fruit. Furthermore, the activities of superoxide dismutase decreased in all chitosan treatments and PCS or/and PCC treatments also changed the activities of polyphenol oxidase, peroxidase and phenylalanine ammonia-lyase. The results indicated the beneficial effect of chitosan by preharvest spray and/or postharvest coating on fruit quality and resistance to fruit decay.
26067827
Effects of chitosan-essential oil coatings on safety and quality of fresh blueberries.
UNLABELLED
Chitosan coating plus different essential oils was developed and applied to fresh blueberries in order to find more natural treatments to preserve fresh fruit quality and safety during postharvest storage. Studies were 1st performed in vitro where wild-type Escherichia coli and Penicillium digitatum were grown in suitable media, and then subjected to 6 essential oils. Three compounds, carvacrol (CAR), cinnamaldehyde (CIN), and trans-cinnamaldehyde (ECIN) had high antimicrobial capacity and were selected for an in vivo study for postharvest storage of blueberries. The selected essential oils, 0.5% each, were added into a chitosan solution and coated on fresh blueberries. After storage at 5, 10, and 20 °C for various days, fruit firmness and microbial populations were evaluated. The chitosan coating substantially decreased bacteria and yeasts/molds on the fruit, and all 3 essential oils added to the antimicrobial activities. Further dosage experiments showed that the antimicrobial activity remained even when lowering CAR concentration to 0.1% and ECIN to 0.2%. Chitosan, CAR, and ECIN also maintained fruit firmness. Our results suggest that chitosan coatings containing essential oils are effective in extending the shelf life of fresh blueberries.


PRACTICAL APPLICATION
Blueberries are high-value fruit with strong antioxidant capacity and other health-promoting benefits. However, microbial food safety is an increasing concern, and decay and softening limits their storability. A combination of ≥ 0.1% CAR or ≥ 0.2% ECIN with a chitosan coating effectively reduced softening of fresh berries and decay by inhibiting microbial growth.
90767366
in vitro response of Colletotrichum to chitosan. Effect on incidence and quality on tropical fruit. Enzymatic expression in mango
Colletotrichum is considered one of the fungal genera with the greatest diversity of species of phytopathogenic fungi and with a wide range of hosts including tropical fruits. In this study, the concentration of chitosan applied was a key factor in the in vitro inhibition of the three Colletotrichum isolates with the most sensitive being the one from banana. Germination was the development stage most affected by the application of this polymer. At the end of 10 days of storage, control of anthracnose in soursop, mango and banana fruit was considerable with the application of 1 % chitosan, with 80 to 100 % inhibition. Likewise, the ripening process of fruit with and without chitosan was generally similar. Activity of the peroxidase (POD) and polyphenol oxidase (PPO) enzymes was observed only in fruit of mango cv. 'Tommy Atkins,' inoculated and non-inoculated with C. gloeosporioides, the activity of both enzymes was higher in the chitosan treatments and the 1.0 % concentration was able to induce gene expression of POD and PPO, occurring until 24 h.
91731358
Effects of chitosan treatment on avocado postharvest diseases and expression of phenylalanine ammonia-lyase, chitinase and lipoxygenase genes
Abstract Stem-end rot (Lasiodiplodia theobromae) and anthracnose (Colletotrichum gloeosporioides) are major postharvest diseases in avocado that cause severe postharvest losses throughout the supply chain. One of the strategies to reduce development of such decay agents resides in the application of resistance inducers (e.g. chitosan), capable of reducing fungal growth and inducing resistance in fruit tissues. The influence of chitosan treatment (1% or 1.5% w/v) was investigated on decay incidence, gene expression of phenylalanine ammonia-lyase (PAL), chitinase (CHI) and lipoxygenase (LOX) and antioxidant enzyme activity [superoxide dismutase (SOD) and catalase (CAT)] in i) drop-inoculated (without wounding) or ii) artificially infected (with wounding) avocado (cv. ‘Hass’) with L. theobromae or C. gloeosporioides pathogens and also in iii) naturally infected (natural inoculum) avocado. Fruit were dipped in 1% or 1.5% w/v chitosan dissolved in water for 3 min, followed by storage for 14 d and 28 d respectively at 7.5 °C, and thereafter for 5 d at 18 °C to simulate market shelf conditions. Chitosan at 1.5% significantly reduced the incidence of stem-end rot and anthracnose in both inoculated and naturally infected avocados. The up-regulation of PAL and down-regulation of LOX genes moderately allowed higher epicatechin contents (90 mg kg−1 FW) in the exocarp, which could have contributed to improved anthracnose control. The up-regulation of CHI genes and higher SOD activity could have contributed to control of stem-end rot. Chitosan solution (1.5%) retained moderate levels of C7 sugars and firmness up to 5 d shelf life. The control of stem-end rot and anthracnose of avocados obtained with 1.5% chitosan can be ascribed to a combination of its antifungal and eliciting properties.
18563649
Comparative epidemiology of Colletotrichum species from mango in northeastern Brazil
Anthracnose, caused by various species of Colletotrichum, is the most common disease affecting mango trees in northeastern Brazil. This disease limits production and drastically reduces fruit quality, which directly affects the export of the fruit. In this study, we investigated the virulence of five species of Colletotrichum prevalent in the orchards of Northeastern Brazil (C. asianum, C. dianesei, C. fructicola, C. karstii and C. tropicale) with respect to three mango cultivars and four alternative hosts. We also determined the influence of temperature on the severity of the disease induced by these Colletotrichum species and the effect of fungicides on the mycelial growth of the fungi. In general, the mango cultivars were susceptible to the five Colletotrichum spp., although C. karstii did not cause an infection in the Palmer and Keith cultivars. All Colletotrichum species exhibited low virulence in the Tommy Atkins cultivar. The Colletotrichum species were pathogenic on the alternative hosts (papaya, banana, guava and bell pepper). Our results suggest that these alternative hosts may serve as a potential inoculum source. For the Colletotrichum species, temperatures between 25 and 30 °C produced larger lesions; however, the different species exhibited different thermal requirements for maximum virulence in the fruits. The Colletotrichum species demonstrated reduced mycelial growth in the presence of thiophanate-methyl, difenoconazole and azoxystrobin fungicides, regardless of the active ingredient. The sensitivity response varied according to the fungicide and the species of Colletotrichum.