Last time, the possibility of bacteria to the existence in the composite community named biofilms, which can take place in the external environment and in the human body. The effect on the human microbial biofilms can be divided into physiological and pathological. Examples of physiological biofilms is indyhenna vaginal microbiota. The first and most important factor of the process of biofilm formation is the ability of microorganisms to adherence. The existence of bacteria in a film culture qualitatively changed views on the pathogenesis, treatment and prevention of infectious diseases. The aim was to investigate the adhesive properties, hemolytic, lipase, lecitinase activity and sensitivity to antibiotics of Staphylococcus epidermidis biofilm-forming strains. For all biofilm-forming strains studied the pathogenicity factors. Studying of pathogenicity factors of the film-forming strains showed that complete hemolysis (zone diameter was 16,0 ± 4,0 mm) on the blood agar and lipase activity (diameter of zone 5,0 ± 1,0 mm) was shown by all the film-forming strains of S. epidermidis, lecitinase activity was observed in 80% (zone diameter of 5,0 ± 1,0 mm) on the yolk-salt agar. It was found that all the film forming strains of S.epidermidis can adhesion to cells of human buccal epithelium. It was found that all 10 film-forming strains of S. epidermidis were high-adherens with the medium adhesion equal to 8.61. Among the investigated film-forming strains he highest MAR was 11.1, while participating in the adhesion of epithelial cells was 92.85 %, and IMA – 11.84. It was found that most of the studied biofilm-forming strains of S. epidermidis was resistant to penicillin – 90%, oxacillin – 80%, erythromycin – 70%, and oleandomycin – 70% and susceptibility to cephalosporins, such as ceftriaxone, cefuroxime and tseftazydimu. It was found that resistance to ceftriaxone was observed in 20% of strains, to cefuroxime and tseftazidim – 40% biofilm-formind strains. In the study of resistance to antibiotics of tetracycline class found that among 10 biofilm-forming strains of S. epidermidis were 40% resistant to tetracycline and by 30% to doxycycline hydrochloride. It was established that most of the studied strains of S. epidermidis were resistant to antibiotics from the class penicillin, and sensitive – to cephalosporins. Thus, high levels of hemolytic, lipase and lecitinase activity of isolated film-forming strains of S. epidermidis can oppose and suppress the defense mechanisms of the host organism, on the one hand, and an intense adhesion due to high adhesive capacity – on the other, that leading to the active colonization of damaged and intact organs, along with other factors of pathogenicity of these microorganisms to create the conditions for long-term persistence in the body and leads to chronic infectious processes.
Keywords: biofilm, biofilm-forming strains, ability to adhere, hemolytic, lipase, letsytinase activity, S. epidermidis
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