Antioxidant and Antidiabetic Activities of Leaf Extracts of Lepisanthes senegalensis (Sapindaceae)

Abstract

Lepisanthes senegalensis is a medicinal plant traditionally used for the management of several health conditions. This study evaluated the antioxidant activity and in vitro α-amylase inhibitory potential of aqueous and hydroethanolic leaf extracts of L. senegalensis. The extracts were obtained by maceration using water or a water–ethanol mixture. Antioxidant activity was investigated using the DPPH free-radical scavenging and CUPRAC reducing assays, with ascorbic acid as the reference compound. α-Amylase inhibitory activity was evaluated using acarbose as the reference inhibitor. In the DPPH assay, the aqueous and hydroethanolic extracts exhibited IC50 values of 587.00 and 553.77 µg/mL, respectively, compared with 10.77 µg/mL for ascorbic acid, indicating relatively weak radical-scavenging activity. In the CUPRAC assay, the hydroethanolic extract demonstrated stronger reducing activity than the aqueous extract, with RC50 values of 1.98 and 14.62 µg/mL, respectively; the reference ascorbic acid showed an RC50 of 1.52 µg/mL. The hydroethanolic extract also showed greater α-amylase inhibitory activity than the aqueous extract, with IC50 values of 68.78 and 463.55 µg/mL, respectively, whereas acarbose had an IC50 of 0.18 µg/mL. Overall, the hydroethanolic extract demonstrated greater activity across the assays investigated. These findings indicate antioxidant and α-amylase inhibitory potential in the leaves of L. senegalensis and support further investigation of their bioactive constituents.