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 125μg/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.

Plants from The Genus Daphne: A Review of its Traditional Uses, Phytochemistry, Biological and Pharmacological Activity

“…alpina, Daphne cneorum L. (Garland flower or Rose Daphne), Daphne blagayana L. Freyer and Daphne malyana Blečić) exhibit significant antioxidant and antimicrobial activities. Analysis of the chemical composition of these species has demonstrated the presence of different secondary metabolites that belongs to the groups of coumarins, phenolic acids and flavonoids, which are considered to be responsible for their biological activitiy (37,40,41,85,86).…”

Daphnetin: A bioactive natural coumarin with diverse therapeutic potentials

“…Depending on their structure, there are simple, dimeric or trimeric coumarins. Daphne contains various coumarins including: daphnetin, DAP-8-glucoside, daphnin, esculin, umbelliferone, and acetil-umbelliferon (Manojlović et al, 2012;Sovrlić et al, 2015). Rutarensin, daphnoretin, daphneretusin-A, dimethyl-daphnoretin-7-O-glucoside are categorized among dimeric coumarins while trimeric coumarin metabolites i.e., daphneretusin B, and triumbellin were also identified in Daphne species (Mansoor et al, 2013).…”