Ultrasound-Assisted Extraction of Antioxidants and Neuroprotective Compounds from Banana Flowers via Simplex-Centroid Solvent Optimization

Banana ( Musa paradisiaca ) flowers are rich in bioactive compounds with antioxidant, anti-inflammatory, and neuroprotective potential. This study optimized the extraction of flavonoids, phenolic acids, and aldehyde, as well as neuroprotective compounds, specifically tryptophan and serotonin, using ultrasound-assisted extraction (UAE) coupled with a simplex-centroid solvent mixture design. Four solvents—water, methanol, ethanol, and acetonitrile—were evaluated in 15 combinations, with bioactive compounds quantified via Ultra-Performance Liquid Chromatography coupled with Photodiode Array detection. The quadratic model used in optimization achieved high regression, with R² values ranging from 91 to 98%. Optimal solvent ratios were water:acetonitrile (51:49) for flavonoids (hesperidin, quercetin-3-glucoside, and epigallocatechin gallate), water:methanol:ethanol (32:63:5) for phenolic acids and aldehyde (protocatechuic aldehyde, syringic acid, and isoferulic acid), and water:acetonitrile (84:16) for neuroprotective compounds (tryptophan and serotonin). Quantification was conducted across seven banana flower varieties, revealing substantial differences in compound levels. These variations suggest the potential to select superior varieties for targeted functional uses. While optimization was based on pooled data, the solvent system is broadly applicable across cultivars. Overall, the developed UAE method provides a high-efficiency, eco-friendly approach for extracting bioactive compounds, highlighting its potential applications in food, pharmaceutical, and nutraceutical industries.