This study explores the novel utilization of Butea monosperma (Palash) flowers as a kombucha substrate instead of traditional black or green tea, providing new insights into plant-based fermentation systems and expanding the diversity of functional beverages. A traditional Indian medicinal flower, B. monosperma, is coveted for its abundance of flavonoids and polyphenols. The objectives were to evaluate changes in metabolomic and phytochemical processes over the 14-day fermentation period. While titratable acidity elevated to 1.95%, the fermentation process significantly reduced pH from 3.32 to 2.72 and total soluble solids from 11 to 5 °Brix. Diphenyl-1-picrylhydrazyl radical scavenging assay increased by 22.78% in the kombucha, indicating a significant improvement in antioxidant activity. Moreover, total phenolic content increased from 126.77 to 263.54 mg gallic acid equivalents/100 g, depicting enhanced bioactive potential. Additionally, total flavonoid content increased to 98.12 mg quercetin equivalents/ml. Attenuated total reflectance Fourier transform infrared spectroscopy confirmed the formation of functional compounds, including hydroxyl, carbonyl, and aromatic groups, indicative of the development of organic acids and polyphenols. High-resolution accurate mass spectrometry analysis demonstrated newly formed metabolites, such as homobutein 4-glucoside, quercetin-3β-D-glucoside, and salicylic acid derivatives, supporting robust microbial biotransformation and metabolic enrichment. Microbial growth increased from day 1 to 6.65 and day 14 to 9.18 logarithmic colony-forming units per milliliter over the fermentation period. These findings demonstrate that fermentation effectively enhances the bioactivity of B. monosperma , supporting its potential as a functional, antioxidant-rich fermented beverage and highlighting the value of traditional Indian botanicals in food innovation.
Bharti et al. (Fri,) studied this question.