Evaluation of alpha-amylase and alpha-glucosidase inhibitory potentials of various fractions of Chasmanthera dependens (Hochst.): an integrated in vitro and molecular docking study.

Abstract

Chasmanthera dependens is traditionally used for managing various ailments, including type-2 diabetes mellitus. However, scientific validation of its anti-diabetic mechanisms remains limited. This study evaluated the alpha-amylase and alpha-glucosidase inhibitory activities of C. dependens root extracts and fractions, and investigated the binding mechanisms of its phytoconstituents through molecular docking. Crude methanol extract and three fractions (dichloromethane, ethyl acetate, and butanol) of C. dependens root were assessed for in vitro inhibitory effects against alpha-glucosidase and alpha-amylase using spectrophotometric methods. Molecular docking simulations were performed using AutoDock Vina to predict binding affinities and interaction modes of identified compounds with both enzyme active sites. All fractions demonstrated significant enzyme inhibitory activities. The ethyl acetate fraction exhibited superior inhibition against both alpha-amylase and alpha-glucosidase compared to acarbose (p < 0.0001). Molecular docking revealed that rutin, epicatechin, and sapogenin showed strong binding affinities (−7.6 to −10.0 Kcal/mol) with favorable interactions at catalytic residues of both enzymes. Rutin demonstrated the highest binding affinity (−10.0 Kcal/mol) for alpha-glucosidase, while epicatechin showed preferential binding to alpha-amylase (−8.5 Kcal/mol). This study provides scientific evidence supporting the traditional use of C. dependens for managing hyperglycemia.