Effect of Hemerocallis Fulva L. Extracts on Some Strains of Microorganisms

Abstract

Introduction. Expanding the species composition of plantsthatcanbeusedas medicinal plant material (MPM) and/oredi blerequires their comprehensivere search. This special lyapplie toint roduced species, for example Hemerocallis fulvaL., whichunder favorable conditionscan reproducequickly, and allow sobtaining a sufficientamount of MРM.
 The objectives of this study were to investigate the contents of total polyphenol compounds, flavonoids and hydroxycinnamic acidsin water-ethanolic extracts of leaves and flowers of Hemerocallis fulva and their antimicrobial activity.
 Research methods. Aqueous-ethanol (AE) extracts were made from leaves and flowers in accordance with the requirements of the State Pharmacopoeia of Ukraine. The content of phenolic compounds, flavonoids and hydroxycinnamic acids was determined spectrophotometrically. The antibacterial and anti-candidal effect of the extracts was determined by the method of diffusion in agar. Antimicrobial activity was evaluated by the diameter of the growth retardation zone.
 Results and discussion. We found that aqueous-ethanol extracts of the flowers and leaves of H.fulva during flowering were rich in phenolics. The highest content of all investigated groups of compounds is shown in flower extracts. Among the investigated extracts, it was found that flower extracts prepared with 60% and 96% AE have the highest total phenolic acids, flavonoids, and hydroxycinnamic acids content (beside extract prepared with 96% ethanol, which didn't have highest hydroxycinnamic acids content). The content of polyphenols, depending on the extragent, was 16.94-149.80 mg/g of dry weight (DW) in gallic acid equivalent, and in flowers it was 529.60-937.07 mg/g of DW in gallic acid equivalent. The content of flavonoids in the leaves is 121.30-180.30 μg/g of DW in quercetin equivalent; in flowers 234.30-254.30 μg/g of DW in quercetinequivalent.
 Extracts prepared with 20, 60, 96% AE have pronounced inhibitory activities against all investigated bacteria strains as well as both investigated Candida spp., but the maximum inhibition zone has been shown for extract prepared with 96% AE against C. pseudotropicalis(23.0-24.0 mm diameter of the zone of growth retardation) and Bacillus subtilis (17.6-20.0 mm diameterofthezoneofgrowthretardation).
 Conclusions. The study results indicate that Hemerocallis fulva L. leaves and flower water-ethanolic extracts as high quantity of polyphenolics may have promising properties in supporting therapy as antibacterial and anticandidal drugs. The leaves and flowers of Hemerocallis fulva have a high content of polyphenolic compounds, flavonoids and hydroxycinnamic acids, as well as antimicrobial effects on Bacillus subtilis, Staphylococcus albus, Escherichia coli, Micrococcus luteus, Candida pseudotropicalis, Candida parapsilosis, and therefore the potential for further research and use to, for example, as a functional food product, as well as for the prevention or treatment of various diseases associated with oxidative stress and inflammation.