Antimicrobial activity and HPLC analysis of Daphne blagayana L. (Thymelaeceae) extracts

Abstract

The aim of this study was to investigate the antimicrobial activity and HPLC analysis of the methanol and chloroform extracts of leaves and twigs of endemic species Daphne blagayana collected from the area of Suva Mountain, Serbia. The antimicrobial activity, expressed as the values of MIC, were investigated on the 6 standardized bacterial strains and two strains of fungi. Amracin and ketoconazole are used as standard antibiotics. MIC values of the tested extracts were ranged from 15.62 to 125 μg/ml. The strongest effect of the extracts exhibited against Klebsiella pneumoniae, Staphylococcus aureus and Proteus mirabilis. Results of the HPLC analysis showed the presence of a variety of secondary metabolites, one of which is 7,8-dihydroxycoumarin (daphnetin), which was identified in all the extracts tested. Daphnetin, as biologically active substance, is most responsible for the antimicrobial activity of the tested extracts, but its role can not exclude the influence of other secondary metabolites (phenols and flavonoids) present in the extracts, which may have a synergistic effect.

Keywords

• Daphne blagayana
• HPLC
• dafnetin
• antimicrobial activity