Influence of Extraction Technique and Solvent on the Recovery of Bioactive Compounds from Eugenia uniflora L. Fruits: Antioxidant, Antimicrobial, and UHPLC-MS/MS Characterization

Abstract

Fruits of Eugenia uniflora L. are rich in phenolic compounds and flavonoids, highlighting their potential as a source of bioactive compounds for nutraceutical development; however, extraction conditions can substantially influence the chemical composition and biological activity of the resulting extracts. This study evaluated the effects of extraction technique and solvent on the bioactive potential of E. uniflora fruit extracts. Powdered fruits were extracted by maceration, infusion, infusion followed by ethanol precipitation, and high-shear homogenization-assisted extraction (HSH) using water or 70% ethanol. Extracts were evaluated for yield, antioxidant capacity (DPPH, ABTS•+, and FRAP), antimicrobial activity against six species, and chemical composition by UHPLC–MS/MS. HSH with 70% ethanol exhibited the highest DPPH (54.16 µmol Trolox equivalents g−1) and FRAP (96.83 µmol Fe2+ g−1) responses, whereas ethanolic maceration showed the highest ABTS•+ scavenging capacity (170.59 µmol Trolox equivalents g−1). The ethanolic extracts showed greater antibacterial activity, particularly against E. coli (MIC = 6.51 µg mL−1) and S. epidermidis (MIC = 15.63 µg mL−1). UHPLC–MS/MS revealed diverse metabolites, with citric acid, quinic acid, and quercitrin showing prominent chromatographic peak areas, alongside other flavonoids, phenolic compounds, and organic acids. Overall, HSH with 70% ethanol provided the most balanced performance, supporting its potential as an efficient strategy for obtaining E. uniflora extracts with nutraceutical potential.