Evaluation of antioxidant, antimicrobial, and cytotoxic activities of Teucrium kotschyanum Poech

The genus Teucrium L. (Lamiaceae) are native to the Mediterranean region and they are known for their antioxidant, antimicrobial, antidiabetic, anti-inflammatory activities [ 1 ]. There are 48 species of this genus in Türkiye, 18 of which are endemic [ 2 ]. The taxon Teucrium kotschyanum Poech remains underexplored and requires further research to fully elucidate its phytochemical and biological properties. The antioxidant activities were evaluated in ethyl acetate and 70% ethanol extracts from T. kotschyanum . The total phenolic content (TPC) was 64.5±0.07 mg GAE/g for ethyl acetate and 74.4±0.05 mg GAE/g for 70% ethanol extract. In the DPPH assay, 70% ethanol extract showed 47.88% inhibition, while ethyl acetate extract showed 30.35%, indicating better antioxidant activity in 70% ethanol. The antimicrobial activity of the extracts was tested by the microdilution method. The antimicrobial MIC values were 1040 μg/mL against Bacillus subtilis , Escherichia coli , and Staphylococcus aureus , 4160 μg/mL against Candida albicans , and 2080 μg/mL against Pseudomonas aeruginosa and Candida krusei . The cytotoxic activity of the extracts was evaluated using the MTT assay and NIH3T3 mouse embryonic fibroblast cells were used for the cytotoxicity test. The IC 50 of the ethyl acetate extract (63.4±0.45 μg/mL) lower than the 70% ethanol extract’s (97.3±0.55 μg/mL), suggesting stronger cytotoxicity in the ethyl acetate extract. These results suggest that T. kotschyanum has potential as a source of bioactive compounds with antioxidant, antimicrobial and cytotoxic effects. Further studies are needed to explore its pharmacological properties. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany