Comparative profiling of secondary metabolites and antidiabetic properties of Anogeissus leiocarpus (DC.) Guill. & Perr. (Combretaceae) extracts

Background: Diabetes mellitus is a chronic metabolic condition which can result in severe long-term complications, and current treatments often have significant side effects. As a result, there is a growing interest in identifying novel α-amylase and α-glucosidase inhibitors with improved safety profiles. Natural products have emerged as a promising source of such compounds. In this study, we investigated the antidiabetic potential of solvent extracts and phenolic compounds from Anogeissus leiocarpus (DC.) Guill. & Perr. Methods: Dried leaves and stem bark were extracted using aqueous and absolute ethanol, yielding ALE, ASE, ELE, and ESE. We assessed their TPC, TFC, and antioxidant capacity. The antidiabetic efficacy of these extracts and their HPLC-identified phenolic compounds was evaluated through in vitro and computational analyses of α-amylase and α-glucosidase inhibition. Results: ASE and ALE demonstrated high polyphenol and flavonoid content, along with strong dose-dependent antioxidant activity (FRAC, TAC, DPPH, and NO scavenging). ASE demonstrated the highest α-amylase inhibition, comparable to metformin ( p > 0.05). Molecular docking analysis showed strong interactions between phenolic compounds and both α-amylase and α-glucosidase, with binding affinities comparable to metformin. Notably, rutin exhibited docking scores of -7.736 and -7.098 kcal/mol for α-amylase and α-glucosidase, respectively, outperforming metformin (-4.305 and -4.094 kcal/mol). Conclusion: These findings suggest that A. leiocarpus and its phenolic compounds hold promise as potent and safer α-amylase and α-glucosidase inhibitors for diabetes treatment.