Identification of Secondary Metabolites of Cyperus rotundus L. and Dose-dependent Effects on Antioxidant Activity and Carbohydrate Digestion Enzymes.

Background: Cyperus rotundus L., commonly known as nutsedge or purple nutgrass, is a resilient herb in the Cyperaceae family with notable pharmacological potential due to its diverse secondary metabolites. This study aimed to identify these metabolites and evaluate the antioxidant and enzyme inhibitory activities of the crude methanol extract of C. rotundus.

Methods: The crude methanol extract of C. rotundus was prepared, and its antioxidant activity was assessed using the DPPH scavenging assay. Additionally, in vitro inhibitory effects against the enzymes: α-amylase and α-glucosidase were evaluated. The secondary metabolites present in the extract were identified using ESI-MS/MS analysis.

Results: ESI-MS/MS analysis revealed the presence of various secondary metabolites, including rutin, quercetin, β-sitosterol, limonene, and beta-pinene. The crude methanol extract exhibited strong antioxidant activity and significant inhibition of α-amylase and α-glucosidase enzymes, which play crucial roles in carbohydrate digestion.

Conclusion: The findings indicate that the crude methanol extract of C. rotundus possesses notable antioxidant properties and the potential to inhibit key enzymes involved in carbohydrate metabolism. This study enhances our understanding of the bioactive compounds in C. rotundus and suggests its therapeutic applications for managing conditions related to carbohydrate metabolism.