Indian medicinal plants known to contain intestinal glucosidase inhibitors also inhibit pancreatic lipase activity—An ideal situation for obesity control by herbal drugs

Dietary excess of lipids causes substantial health disorders like hyperlipemia, obesity and cardiovascular problems. Use of lipase and α-glucosidase inhibitors in combination is considered to be the ideal therapy for obesity control. Anti-obesity activity of natural products is usually assessed by inhibition of pancreatic lipase activity by the preparations. We have reported earlier that some known hypoglycemic medicinal plants, such as, Eugenia jambolana Lam., Azadirachta indica A. Juss., Tinospora cordifolia (Thunb.) Miers and Trigonella foenum-graceum L. contain α-glucosidase inhibitors. The present study reports that their plant extracts also inhibit pancreatic lipase activity. The methanolic extracts showed an IC50 value (μg/mL) of 230+20, 520+15, 360+25 and 564+12 for E. jambolana (stem-bark), A. indica (root), T. cordifolia (leaves) and T. foenum-graceum (seeds), respectively. Bioassay guided partial purification yielded active fractions with IC50 (μg/mL) of 23+5 (E. jambolana), 14+3 (A. indica) and 11+2.5 (T. cordifolia). All the active fractions inhibited the enzyme in a mixed-competitive manner with Ki and Ki’ values (μg/mL) as 1.26+0.22, 3.96+0.28 (E. jambolana); 0.95+0.46, 2.3+0.16 (A. indica); and 1.1+0.2, 4.2+0.26 (T. cordifolia).