Chiang Mai Journal of Science

maximum extractive yield is 3.28 %. For determination of nutritive value, nutritive elements per 100 grams of methanolic extracts of tuber contain 46.43mg of carbohydrates, 21.17mg of protein, 5 mg crude fibres, 0.225 mg calcium, 0.124 mg magnesium, 0.049 mg phosphorus, 0.051 mg vitamin C and 288.4 calori. Alpha Amylase inhibition assay by DNS method 

revealed that the methanolic extract inhibited a-amylase enzyme activity 75.76, 81.52 and 

98.55% at 0.1, 0.5 and 1 mg/ml concentration respectively and is comparable to standard reference of acarbose. Alpha amylase inhibitory effect of methanolic extract was found to be competitive. Phytochemical constituents present in the methanolic extract are tannins, alkaloids, saponins, steroids and phenolic compound. GC-MS and LC-MS analysis of methanolic extracts for characterization of bioactive compound. The bioactive compound(s) revealed that the amylase inhibition in the methanol extract of tuber could possibly contribute to the antidiabetic activity.