Quercus cerris extracts limit Staphylococcus aureus biofilm formation

Abstract

Ethnopharmacological relevance Quercus cerris L., Fagaceae has been used in traditional Mediterranean medicine for numerous purposes, including anti-infective therapies for diarrhea and wound care. Aim of the study To evaluate the anti-staphylococcal activity of fractions of ethanolic extracts of Q. cerris leaf and stem/fruit samples in models for biofilm and growth inhibition. Materials and methods Ethanolic extracts of Q. cerris leaves and stems/fruits were prepared, resuspended in water and fractioned by successively partitioning with hexane, ethyl acetate and butanol. The ability of the fractions to inhibit Staphylococcus aureus biofilm formation was tested using static crystal violet staining methods and confocal laser scanning microscopy. Growth studies were conducted to determine if the diminished capacity to form a biofilm was related to growth inhibition. Results The butanol extracts of both the leaf and stem/fruit samples were the most active, and at a dose of 200 μg/ml, the capacity to form a biofilm was limited to a level equivalent to that of the sarA mutant controls. Further examination of the impact of these fractions on S. aureus growth revealed that biofilm inhibition by the leaf butanol fraction was due to its bacteriostatic activity. The stem/fruit butanol fraction, however, showed a limited impact on growth, thus demonstrating that biofilm inhibition in this case is not related to the bacteriostatic activity of the extract. Conclusion Our evaluation of a medicinal plant used in Mediterranean ethnotherapies for infectious disease has demonstrated significant activity in the inhibition of staphylococcal biofilm formation with a mechanism unrelated to staphylococcal growth inhibition. These results contribute towards validation of this botanical remedy and form the groundwork for future studies in the search for novel biofilm inhibiting drugs.

Inhibition of Staphylococcus aureus biofilm by Lactobacillus isolated from fine cocoa

“…S. aureus CCMB262 biofilm viability was assessed according to Hobby et al (2012) with some modifications [20]. S. aureus CCMB262 was cultured in TSB with 1 % Glc for 18 h at 37 °C in 12-well culture plates (Costar®) containing 18 mm coverslips.…”

Effects of dietary Persian oak (Quercus brantiivar.persica) fruit extract on survival, growth performance, haematological and immunological parameters in rainbow trout,Oncorhynchus mykiss, fingerlings

“…; Hobby et al . ; Katikia et al . ) have been reported, but there is no report on the effects of oak extract on fish immunity.…”

Biocatalytic potential of Streptomyces spp. isolates from rhizosphere of plants and mycorrhizosphere of fungi

“…In this study, we screened Streptomyces species isolated from rhizosphere soils of plants including two Balkan endemorelict plants ( Ramonda serbica and Ramonda nathaliae ), 11 plants used in traditional medicine ( Papaver rhoeas , Salvia pratensis , Matricaria chamomilla , Urtica dioica , Glechoma hederacea , Taraxacum officinale , Verbascum , Viola sp., Cirsium arvense , Quercus cerris , and Bryum sp. ), and mycorrhizosphere soils of six different fungi ( Lactarius deterrimus , Entoloma sp., Suillus sp, Russula sp., Clitophilus sp., and Tuber brumale ) also utilized in traditional medicine .…”