Antioxidant and antimicrobial activities of Hypericum origanifolium Willd. var. origanifolium

Hypericum origanifolium Willd. var. origanifolium, commonly known as "Lüfer otu". Since the number of studies on this taxon is limited, this study aimed to evaluate its biological activities, especially its antioxidant, and antimicrobial activities. Extracts were prepared with methanol, n-hexane and ethyl acetate solvents from the aerial parts of the plant. In the DPPH· assay, the n-hexane extract exhibited higher antioxidant activity compared to other extracts, with an IC50 value of 0.096±0.021 mg/mL. The highest total phenolic content was observed in the n-hexane extract (75.73±0.016 mg GAE/g extract), while the lowest total phenolic content was found in the ethyl acetate extract (40.42±0.003 mg GAE/g extract). The extracts showed antimicrobial activity against all tested microorganisms at values ranging from 7.81-4000 μg/mL. It was proven to have strong antibacterial activity, especially against S. aureus, B. subtilis, and E. faecalis microorganisms, with its low MIC (minimum inhibitory concentration) value (7.81-62.5 μg/mL). The study's findings show that H. origanifolium var. origanifolium extracts have the potential to be a good source of free radicals. Targeting particular bacterial illnesses may be possible given the notable antibacterial efficacy against particular strains.