Antimicrobial activity of three Scutellaria L. species from Turkey

Abstract

Plant-sourced antimicrobials are known for their therapeutic potency against multi-drug-resistantpathogens. The members of Scutellaria L. have been used to cure several diseases in East Asia, Europe, and NorthAmerica. The genus Scutellaria belonging to Lamiaceae family is composed of around 360 species worldwide and 18species in Turkey. In this study, 36 extracts prepared with different solvents from aerial parts and roots of S. salviifoliaBenth., S. diffusa Benth. and S. pontica C. Koch were investigated for their antimicrobial activity against four bacteria(Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 27853, Staphylococcusaureus ATCC 29213) and three yeasts (Candida albicans ATCC 90028, C. krusei ATCC 6258, C. parapsilosis ATCC 90018)by using the broth microdilution method. Gentamicin, vancomycin and fluconazole were used as positive control.According to our results, all of the tested extracts showed stronger antimicrobial activity against yeasts than bacteria.The chloroform extract of S. salviifolia root showed the highest antifungal effect against C. krusei with 32 μg/ml MICvalue compared with all the tested extracts and the positive control fluconazole (64 μg/ml MIC value).