Alpha-glucosidase Activity of Phenolic-rich Extracts From Several Cucurbit Fruit Vegetables.

Alpha-glucosidase Activity of Phenolic-rich Extracts From Several Cucurbit Fruit Vegetables.

Supriatno a,b Kheng Leong Ooi a & Shaida Fariza Sulaiman a

a School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia.b Department of Biology, Faculty of Teacher Traning and Education, Universitas Syiah Kuala, Darussalam-Banda Aceh 23111, Indonesia.

Abstract

Alpha-glucosidase inhibitors are oral anti-diabetic drugs that prevent the final step in the digestion of carbohydrate to absorbable monosaccharides. Phenolic compounds in plants are often being associated as α-glucosidase inhibitors. Thus, ten phenolic-rich extracts (ranging from 15.55 to 26.89 mg GAE/ mg extract) from seven dried fruit pulps of Benincasa hispida, Lagenaria siceraria, Luffa acutangula, Momordica charantia var. maxima, Sechium edule, Trichosanthes cucumerina and Cucumis melo var. inodorus were selected for this study. The decoctions of these dried pulps (excluding Trichosanthes cucumerina) are traditionally reputed for having anti diabetes property. The results revealed the highest alpha-glucosidase activity of the ethyl acetate extract of Momordica charantia var. maxima with EC50 value of 9.449 mg/ml.  Catechin, gallic acid, gentisic acid, chlorogenic acid, and epicatechin are major phenolic compounds in the extract might be responsible for the activity.

Keywords: Benincasa hispida, Lagenaria siceraria, Luffa acutangula, Momordica charantia, Sechium edule, Trichosanthes cucumerina and Cucumis melo