PHYTOCHEMICAL CHARACTERIZATION AND IN VITRO EVALUATION OF α-AMYLASE AND α-GLUCOSIDE INHIBITRY POTENTIAL OF BERGERA KOENIGII LEAF EXTRACT FOR THE MANAGEMENT OF TYPE 2 DIABETES MELLITUS

The ethanolic extract of Bergera koenigii leaves demonstrated concentration-dependent in vitro inhibitory activity against three mechanistically distinct, clinically relevant antidiabetic targets: α-amylase (80.89% inhibition, IC₅₀ 638 μg/mL), α-glucosidase (80.89% inhibition, IC₅₀ 633 μg/mL), and DPP-4 (78% inhibition at 400 μg/mL). Although less potent than the reference standards acarbose and sitagliptin, this multi-target enzyme-inhibitory profile supports the traditional use of curry leaf in diabetes management and its potential as a source of natural antidiabetic constituents. The findings represent preliminary in vitro evidence rather than proof of clinical efficacy. Future work should include triplicate DPP-4 measurements with reported SD, nonlinear regression to establish a DPP-4 IC₅₀, expanded concentration ranges bracketing the IC₅₀ values, appropriate statistical significance testing, and bioassay-guided fractionation to identify the specific phytoconstituents responsible for the observed activity.

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