Thermoplastic starch Enzymatic modification
139645366
Improvement in adhesion of cellulose fibers to the thermoplastic starch matrix by plasma treatment modification
Abstract This work deals with provision and characterization of the biopolymer based composites achieved by incorporation of cellulose fibers as the reinforcement within the glycerol plasticized matrix formed by thermoplastic cornstarch biopolymer. The function of starch based polymers is limited due to poor mechanical properties. However, it is improved with forming a biocomposite of thermoplastic starch (TPS) as matrix and the cellulose fibers (CF) as reinforcement. The surface of cellulose fibers is successfully modified using the air plasma treatment with the aim of improving the matrix/fiber adhesion. The modified fibers are studied using X ray diffraction (XRD) scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) The TPS/CF composites are prepared using high friction and hot compression procedure. Tensile test results and SEM images of the fracture surfaces show significant improvement of adhesion between treated cellulose fibers and TPS matrix. Thermogravimetric analysis shows a considerable decomposition at approximately 250 350 degC. XRD proved the significant increase in crystallinity percentage of composites compared to TPS.
Composites Part B: Engineering
Mahyar Fazeli Jennifer Paola Florez Renata Antoun Simao
224990377
Modification of Thermoplastic Starch with Natural Fiber
Biofiller Reinforced Biodegradable Polymer Composites
Ridhwan Jumaidin Nur Wardah Adam S M Sapuan
229602091
EFFECT OF ENZYMATIC MODIFICATION OF WHITE CORN FLOUR STARCH ON THE QUALITY OF BREAD FOR PATIENTS DIAGNOSED WITH CELIAC DISEASE
The effect of enzymes with amylolytic activity on the degree of hydrolysis of white corn flour in order to improve the quality of gluten free bread for special nutrition was studied. Starch was hydrolyzed using mushroom a amylase and glucoamylase in an amount of 0.005 and 0.03 by weight of flour, respectively. As a result, the number of sugars increased to 5.0 5.5 The optimal pH value of 4.7 for the action of enzymes was set by adding 0.065 citric acid. Hydrolysis was subjected to 50 of white corn flour from the total amount, the humidity of the hydrolyzate was 65% In addition to mono and disaccharides, the hydrolysate accumulated 3.5 on THE basis of dextrins, of which 1.3 achro and maltodextrins, reducing the degree of stale bread.
Alina A Burnatseva Anna V Khmelevskaya A A Gazzaeva M I Gusalova I T Karaeva
224889168
Enzymatic Modification of Granular Potato Starch Using Isoamylase Investigation of Morphological, Physicochemical, Molecular, and Techno Functional Properties
Marco Ulbrich Saeed A Asiri Robert Bussert Eckhard Floter
226046240
Enzymatic properties of an efficient glucan branching enzyme and its potential application in starch modification.
Glucan branching enzymes (GBEs, EC 2.4.1.18) catalyze the formation of a 1,6 linked branch in starch, which is important for the starch modification with prospective properties. In this study, the aqGBE gene encoding an efficient glucan branching enzyme was cloned from Aquabacterium sp. strain A7 Y and successfully expressed in Escherichia coli BL21 (DE3) The specific activity of the purified recombinant enzyme rAqGBE was 2850 U/mg with potato starch as the optimal substrate, and the Km and Vmax values of rAqGBE were 1.18 mg/mL and 588.2 mmol/min/mg, respectively. Enzymological characterization showed that rAqGBE exhibits its optimal activity under the condition of 40 degC and pH 7.0, respectively, which is independent of calcium ions. Otherwise, rAqGBE treated potato starch showed different chain length distribution compared with control, the numbers of short chains (degree of polymerization, DP<7) and long chains (DP>25) increased from 4.5% to 9.6% and 6.1% to 15.7% after enzymatic treatment, respectively. In starch anti ageing assay, with minimum usage of 0.8 mg rAqGBE per g starch, the rAqGBE treated potato starch exhibited reduced retrogradation properties. Our results indicate that the branching enzyme AqGBE may therefore be a promising tool for the enzymatic modification of starch.
Protein expression and purification
Chengyao Xia Yan Qiao Chaonan Dong Xiaopei Chen Yanxin Wang Ding Li Xianfeng Ye Jian Han Yongchao Huang Zhong-li Cui Zhoukun Li
214412807
Surface Modification of Tapioca Starch by Using the Chemical and Enzymatic Method
Kewalee Prompiputtanapon Waraporn Sorndech Sunanta Tongta
149561611
THE USE OF SUNFLOWER LECITHIN IN THE TECHNOLOGY ON GLUTEN FREE BREAD WITH ENZYMATIC MODIFICATION OF FLOUR STARCH
The necessity of search of new ways to improve the quality of gluten free bread for people suffering from celiac disease is considered in the article. As one of the directions of this problem solution the use of surface active substances has been suggested. The efficiency of the use of sunflower skimmed lecithin for production of rice bread with the use of enzymatic modification of flour starch has been proved. Its influence on the intensity of fermentation in the rice dough, the activity of fermentative microflora and the change of specific volume in the process of maturation has been investigated. The positive influence of emulsifier in the technology of rice bread on the indicators as ready made products, in particular specific volume, porosity and elastic properties of the crumb have been studied out. It was established that the addition of sunflower skimmed lecithin to vegetable oil in the process of production of rice bread using flour starch hydrolysis promotes the extension of its shelf life and freshness.
Iryna Medvid Olena Shydlovska Viktor Dotsenko
224885555
Processing and Modification of Starch into Thermoplastic Materials
Ridhwan Jumaidin Z A S Saidi S M Sapuan
104363969
Chemical modification of cellulose nanocrystals and their application in thermoplastic starch (TPS) and poly(3 hydroxybutyrate) (P3HB) nanocomposites
Paulo Leonardo Lima Ribeiro Tamiris Vilas Boas Figueiredo Livia Eloy Moura Janice Izabel Druzian
182159533
Enzymatic Modification of Granular Potato Starch Effect of Debranching on Morphological, Molecular, and Functional Properties
Starch Starke
Saeed A Asiri Eckhard Floter Marco Ulbrich