Inhibitory effects of chickpea and Tribulus terrestris on lipase, α-amylase and α-glucosidase

• The content of total saponin in chickpea was found higher than Tribulus terrestris.
• Saponin is generally regarded as having low biological availability.
• Tribulus terrestris and chickpea are potent inhibitors of lipase, α-amylase and α-glucosidase activity.
• Lowest DEIC50 values for both chickpea and Tribulus terrestris were for α-glucosidase.

The total saponin content and its in vitro bioaccessibilities in Tribulus terrestris and chickpea were determined by a static in vitro digestion method (COST FA1005 Action INFOGEST). Also, in vitro inhibitory effects of the chosen food samples on lipid and starch digestive enzymes were determined by evaluating the lipase, α-amylase and α-glucosidase activities. The tested T. terrestris and chickpea showed inhibitory activity against α-glucosidase (IC50 6967 ± 343 and 2885 ± 85.4 μg/ml, respectively) and α-amylase (IC50 343 ± 26.2 and 167 ± 6.12 μg/ml, respectively). The inhibitory activities of T. terrestris and chickpea against lipase were 15.3 ± 2.03 and 9.74 ± 1.09 μg/ml, respectively. The present study provides the first evidence that these food samples (T. terrestris, chickpea) are potent inhibitors of key enzymes in digestion of carbohydrates and lipids in vitro.