Methicilin-resistant Staphylococcus xylosus isolated from horses and their sensitivity to enterocins and herbal substances

Abstract

Methicillin-resistant (MR) strains S. xylosus from faeces of horses were tested for their sensitivity to enterocins (Ents) and herbal substances (oregano, sage) to contribute to basic research related to Ents and horses microbiota. The counts of staphylococci in fecal samples of 122 horses reached log10 2.03±0.42 colony forming units per gram. Twelve staphylococcal isolates were found to be MR and they were taxonomically allotted to the species S. xylosus. The strains produced lactic acid at average of 1.04±0.004 mmo/l. Six strains were not sensitive to Ents used; however, they were sensitive to oregano and sage substances reaching inhibitory zones in size of 17-31 mm. The other strains were sensitive at least to 3 of 5 Ents tested (inhibitory activity 100 - 12 800 AU/ml) and they were also sensitive to both herbal substances. In general, the growth of the strains S. xylosus was inhibited by oregano and sage substances; however, the inhibitory zones due to oregano possessed 28 mm in average and due to sage 12 mm in average. The strains were less sensitive to Ents than to herbals.