In Vitro Evaluation of the Antidiabetic Potential of Bergera koenigii (Curry Leaf) Leaf Extract through Inhibition of α-Amylase, α-Glucosidase and Dipeptidyl Peptidase-4 (DPP-4) Enzymes

The ethanolic leaf extract of Bergera koenigii showed a positive and broad phytochemical profile and exhibited concentration-dependent inhibitory activity against α-amylase, α-glucosidase and DPP-4, three key enzymatic targets in the management of Type 2 Diabetes Mellitus. α-Amylase inhibition increased from 5.91% to 39.18%, α-glucosidase inhibition from 6.20% to 40.02%, and DPP-4 inhibition from 18% to 78% across the 25–400 µg/mL concentration range, with the extract's DPP-4 inhibition at 400 µg/mL (78%) approaching that of sitagliptin (85%). These findings support Bergera koenigii as a promising natural source of antidiabetic enzyme inhibitors and justify further investigation, including IC₅₀ determination, active-constituent isolation, and in vivo evaluation, before its potential therapeutic application can be established.

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