Restrictions of the Extraction Process and Bioactivities of Trachyspermum Ammi Seed Extract

www.mjms.usm.my © Penerbit Universiti Sains Malaysia, 2022 This work is licensed under the terms of the Creative Commons Attribution (CC BY) (http://creativecommons.org/licenses/by/4.0/). 173 Dear Editor, I read with interest the manuscript titled ‘Evaluation of antibacterial synergism of methanolic extract of Dracocephalum kotschyi and Trachyspermum ammi’ by ZareiYazdeli et al. (1), in which the authors reported that T. ammi seed extract (TASE) inhibited some pathogenic microorganisms such as Pseudomonas aeruginosa, Shigella dysenteriae, Escherichia coli and Staphylococcus aureus. The paper stated that seed extract from this plant can be considered as a phytochemical preservative in the food industry in the future. However, whilst there are some studies about TASE, it seems to me that the studies relating to the extraction process, biological effects and chemical components of this material are still insufficient. T. ammi is commonly known as ajwain or ajowan. All parts of this plant can be used in medicine, especially the seeds, which contains carbohydrates, fibre, tannins, glycosides, protein, fat, saponins, flavones and minerals while the essential oil (EO) of the seeds possesses a large amount of precious components, including γ-terpinene, p-cymene and thymol. This material has many medical applications, such as antifungal, antioxidant, antimicrobial, antinociceptive, cytotoxic, hypolipidemic, antihypertensive, antispasmodic, broncho-dilating actions, antilithiasis, diuretic, abortifacient, antitussive, nematicidal, anthelmintic and antifilarial (2). Nowadays, to research on the biological effects of T. ammi seeds, scientists have to extract the bioactive compounds using hydrodistillation methods to separate the EO and conventional extraction methods to isolate the extract. In this study, we only deal with the extraction process of the T. ammi seeds. As we know, solvent plays an important role in the extraction process. For studies involving the extract of T. ammi seeds, only pure solvents were used for the extraction, such as methanol (1); ethanol, methanol, n-hexane and ethyl acetate (3); and n-hexane, chloroform and methanol (4). Bioactivity in the extract depends significantly on the polarity of the solvent. In these studies, although the polarity level increases from n-hexane to methanol, water was not used to form an aqueous solvent system. With the presence of water, there are many choices for different polarity levels; hence, the yield of the extraction process can be improved and the bioactivity of the extract enhanced. Using conventional extraction also wastes time: Rajput et al. (5) used the maceration method to extract chemical components in T. ammi seeds for 30 days, and Zarei-Yazdeli et al. (1) also spent nearly 8 h, using the Soxhlet machine to isolate extract. This shows that conventional extraction methods, such as maceration or Soxhlet, are not suitable at this time, because of the long extraction time and high operating costs. Nowadays, there are some modern extraction methods that can be used for extracting bioactive compounds from this material, such as microwave-assisted extraction, ultrasoundassisted extraction, enzyme-assisted extraction, supercritical fluid extraction, etc. These methods are green extraction methods, saving time To cite this article: Quoc LPT. Restrictions of the extraction process and bioactivities of Trachyspermum ammi seed extract. Malays J Med Sci. 2022;29(6):173–175. https://doi.org/10.21315/mjms2022.29.6.18