Chemical Composition, Biocompatibility, and Anti-Candida albicans Activity of Schinus weinmanniifolia Mart. ex Engl.: First Report on Its Potential Use in Traditional Medicine

Recurrent vulvovaginal candidiasis (RVVC), predominantly caused by Candida albicans, represents a global health issue, particularly in developing regions. This study explores the antifungal potential of aqueous leaf extract of Schinus weinmanniifolia Mart. ex Engl., a native Latin American plant. The extract was evaluated for phytochemical composition, antifungal efficacy and safety profile. Phytochemical analyses identified six major compounds, including shikimic acid, gallic acid and methyl gallate, with antioxidant and antimicrobial properties. The extract showed potent antioxidant activity, with IC50 values between 1.52-5.51 µg/mL. It strongly inhibited C. albicans, with a minimum inhibitory concentration (MIC) of 1.95 µg/mL, and was active against other yeasts (MIC 0.48–62.5 µg/mL). The growth kinetics assay revealed reduced C. albicans viability after 12 hours at 2×MIC versus the positive control. Scanning electron microscopy confirmed reduced fungal counts without morphological damage. The extract impaired C. albicans virulence, reducing germ tube formation by 75.49% and hyphal transition by 84.34%, outperforming fluconazole. Biocompatibility assays showed it is non-hemolytic (IC50 >1000 µg/mL), non-mutagenic, and highly selective for fungal cells (SI = 512.82), suggesting minimal human cell toxicity. In conclusion, the extract combines strong antifungal activity and favorable safety, with cost-effective preparation suitable for traditional medicine in resource-limited regions.