Comparison of α-amylase, α-glucosidase and lipase inhibitory activity of the phenolic substances in two black legumes of different genera

Abstract

Antioxidant-rich plant foods can inhibit starch and lipid digestions that are relevant to diabetes management. Two high-antioxidant black legumes, black soybean (Glycine max) and black turtle bean (Phaseolus vulgaris), belonging to two different genera were used to investigate their capacity against digestive enzymes. Phenolic substances were compared in crude, semi-purified extracts (semi-purified by XAD-7 column), and fractions (fractionationed by Sephadex LH-20 column) from these two legumes. In addition, their antioxidant capacities and abilities to inhibit digestive enzymes were characterized. Results showed that Fraction V from black soybean was the most effective (IC50: 0.25mg/mL) against α-amylase; Fraction V from black turtle bean was the most potent (IC50: 0.25μg/mL) against α-glucosidase; Fraction IV from black turtle bean was the most powerful (IC50: 76μg/mL) against lipase. Of the pure phenolic compounds tested, myricetin showed the highest inhibition of α-amylase, α-glucosidase and lipase (IC50: 0.38mg/mL, 0.87μg/mL and 15μg/mL, respectively).

Digestive enzyme inhibition activity of the phenolic substances in selected fruits, vegetables and tea as compared to black legumes

“…For legumes, the extraction method was the same as we described before (Tan et al, 2017). For berries, crude extracts were obtained by the method reported previously with some modifications (Velioglu, Mazza, Gao, & Oomah, 1998).…”

“…According to the method reported before, a column packed with XAD-7 were used to remove sugar and organic acids in crude phenolic extracts (Tan et al, 2017). After XAD-7 purification, black turtle bean and black soybean were selected from the 8 types of foods upon the consideration of the results from IC 50 values against aamylase, a-glucosidase and lipase.…”

“…After XAD-7 purification, black turtle bean and black soybean were selected from the 8 types of foods upon the consideration of the results from IC 50 values against aamylase, a-glucosidase and lipase. Column fractionation of semipurified legume extracts were carried out by our previously published method (Tan et al, 2017).…”

“…Data related to legumes have been reported, and the same data are included for comparing with other fruits, vegetables and tea (Tan, Chang, & Zhang, 2017). In addition, seventeen pure phenolic compounds were used to test the IC 50 values against aamylase, a-glucosidase and lipase (Tan et al, 2017).…”

Diabetes Mellitus: A Review on Pathophysiology, Current Status of Oral Pathophysiology, Current Status of Oral Medications and Future Perspectives

“…Inhibition of starch digestive enzymes or glucose transporters can reduce glucose release and absorption in the small intestine. This decrement could help to manage DM 11,12 .…”