Abstract

• In this study, one of the Dioscorea species, Dioscorea alata L. (Myauk U) has been chosen to study nutritional values, chemical composition and some biological activities such as antimicrobial, antioxidant and anti-proliferative activities. The phytochemical constituents were screened by test tube method indicating the presence of alkaloids, -amino acids, carbohydrates, glycosides, phenolic compounds, saponins, starch and terpenoids, however, cyanogenic glycosides, reducing sugars and tannins were absent. The nutritional values of the selected rhizomes were determined by AOAC methods. The antimicrobial activity of the different crude extracts such as pet-ether, ethyl acetate, ethanol and watery extracts was investigated against six microorganisms: Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus pumilus, Candida albicans and Escherichia coli by agar well diffusion method. The total phenolic contents (TPC) of ethanol extract (469.1 ± 0.01 g GAE/mg extract) and watery extract (441.1 ± 0.00 g GAE/mg extract) were determined by Folin-Ciocalteau assay method. The antioxidant activity of ethanol and watery extracts was evaluated by 2, 2 - diphenyl -1- picryl – hydrazyl free radical scavenging assay. Both ethanol and watery extracts were found to possess antioxidant activity. However, both extracts possess weaker in antioxidant activity than standard ascorbic acid. The anti-proliferative activity or cytotoxicity of methanol extract of the rhizome of D. alata was evaluated by MTT assay using Hep G2 (human liver cancer cell).