Optimization of extraction and structural characterization of bioactive compounds from Musa balbisiana peel

Musa balbisiana peel, a largely underutilized by-product, is konwn as a source of bioactive compounds. This study aims to investigate the extraction of polyphenols and saponins from M. balbisiana peel by microwave-assisted extraction (MAE) combined with optimized extraction conditions by response surface methodology (RSM). In addition, the biologically active constituents in the extract were also determined. Phytochemical screening and quantification revealed that the peel extract was rich in polyphenols and saponins, with total polyphenol content (TPC) and total saponin content (TSC) of 48.82 mg GAE/gDM and 57.18 mg/gDM, respectively, under optimal conditions (81.09% solvent concentration, 4.39 s/min irradiation cycle, 44.54 min microwave time). FT-IR and Raman spectroscopy confirmed the presence of characteristic functional groups of polyphenols and saponins. The purified fraction contained oleanolic acid, which was identified as the major compound after improving the extract's purity. These findings provide insights into the chemical composition to explain the biological activity of M. balbisiana peel.