Phytochemical Screening and α-Glucosidase Inhibition of Combined Yacon Leaf and Karas Tulang Root Extracts

Abstract

Diabetes mellitus is a metabolic disorder characterized by persistent hyperglycemia and remains a major global health concern. Natural products containing secondary metabolites are being investigated as potential α-glucosidase inhibitors. This study evaluated the phytochemical profile and in vitro α-glucosidase inhibitory activity of a combined ethanol extract of yacon leaves (Smallanthus sonchifolius) and karas tulang roots (Chloranthus erectus). Phytochemical screening was performed by thin-layer chromatography, and enzyme inhibition was evaluated using p-nitrophenyl-α-D-glucopyranoside as the substrate with acarbose as the positive control. Both extracts contained flavonoids, saponins, tannins, and alkaloids. The combined extract produced concentration-dependent inhibition with an IC₅₀ of 25.5 ± 0.82 µg/mL, whereas acarbose produced an IC₅₀ of 15.5 ± 0.80 µg/mL. The observed activity may be associated with the combined presence of secondary metabolites, particularly phenolic compounds, but a synergistic interaction cannot be concluded because the individual extracts and multiple combination ratios were not tested. The findings support preliminary in vitro α-glucosidase inhibitory potential of the combined extract. Further studies should confirm the extract ratio, identify active compounds, assess toxicity, and evaluate activity in vivo.