Phytochemical investigation of Phyllanthus emblica (Amla) for therapeutic application in urinary tract infection (UTI) management and development of functional tea.

Phyllanthus emblica L. (amla) is a medicinal fruit, rich in secondary metabolites with reported anti-inflammatory and antimicrobial effects. The current study aimed to assess the impact of drying and extraction techniques on phytochemical recovery, the biological potential of P. emblica relevant to the management of urinary tract infection (UTI), and the development of functional tea. Two different processing methods were adopted. Method 1 involves sun-drying of P. emblica and extracting with methanol and ethanol using an orbital shaker at 40 °C. Method 2 involves freeze-drying of P. emblica and then ultrasound-assisted extraction (sonication) using the same solvent system. Results showed that the methanol extract obtained using method 2 yielded the highest phytochemical recovery (TPC 170.18 mg GAE/g) and antioxidant activity (DPPH IC50 208.2 µg/mL; FRAP 35.7 µmol Fe2+/g), compared to the ethanol and method 1 extracts but considerably lower than standard quercetin. The same extract showed notable inhibition against egg albumin (62.6 %), bovine serum albumin (59.5 %) denaturation, delineated more inhibition against COX-2 (IC50 46.7 µg/mL) than COX-1 (IC50 68.2 µg/mL), and notable broad-spectrum antimicrobial activity against Escherichia coli, Klebsiella oxytoca, Citrobacter spp., Candida albicans, and Candida glabrata. Bioassay-guided fractionation of the methanol extract derived from freeze-dried P. emblica yielded three different fractions (A, B, C) using liquid-liquid partitioning. Fraction B (ethyl acetate) outlined enhanced biological potential in all assays except for a slight decline in antifungal activity. Moreover, sub-fractionation by RP-HPLC, which revealed reduced activity, underscores the role of synergistic phytochemical interactions. LC-ESI-MS/MS analysis of fraction B identified gallic acid, ellagic acid, quinic acid, chlorogenic acid, quercetin, and myricetin. Additionally, brewing freeze-dried P. emblica powder as a functional tea retained substantial phenolic content, antioxidant, and antimicrobial potential, while sensory optimization through blending with green tea improved consumer acceptability. The findings suggest that freeze-drying with sonication may effectively preserve bioactive compounds from P. emblica, supporting its potential as a nutraceutical against clinically relevant uropathogens, inflammation, and oxidative stress. However, further in vivo and clinical studies are required to confirm therapeutic efficacy.