Comparative study of Pogostemon benghalensis extracts using different methods: chemical profiling, antibacterial, in vitro pancreatic lipase and diabetic enzyme inhibition activities

The present study aimed to compare three extraction methods for the quantity and identification of phytochemicals from Pogostemon benghalensis leaf extract using FTIR and GC–MS, and to evaluate their antibacterial and pancreatic lipase (PL) enzyme activity. Ultrasonication-assisted extraction (UAE) was found to be the most efficient method for extracting phenols (47.40 mg GAE/g) and flavonoids (31.78 mg RTE/g), suggesting further research on UAE techniques for phenol content. GC–MS analysis identified key bioactive compounds such as eugenol, hexadecenoic acid, and cis-vaccenic acid in all extraction methods. UAE yielded 50 compounds, microwave-assisted extraction (MAE) 39 compounds, and Soxhlet-assisted extraction (SAE) yielded 35 compounds. The UAE extract showed significant antibacterial activity and 57 % PL enzyme inhibition at 100 mg/ml, comparable to the standard drug orlistat. The extract also exhibited dose-dependent inhibition of alpha-amylase and alpha-glucosidase, indicating its potential as an alternative to synthetic drugs. This study provides a comparative analysis of extraction methods for P. benghalensis constituents and their anti-obesity effect in vitro . • Ultrasonication-, microwave- and solvent-extraction were adopted for P. benghalensis leaf. • UAE was the most effective method for high- yield of secondary metabolites. • FTIR and GC–MS revealed the functional groups and compounds in the leaf extract. • UAE-extract showed highest pancreatic lipase enzyme inhibition at 100 mg/mL. • UAE-extract revealed dose-dependent inhibition of α-amylase and α-glucosidase.