Evaluation of the Topical Healing Ability of Purified Exopolysaccharides (EPSs) from Enterococcus faecalis on skin wounds in Male Albino Mice

Abstract

The probiotic bacteria are characterized to produce compounds have an antibacterial potential and working as immunomodulators, the purpose of this study is evaluation the antibacterial activity and topical healing ability of exopolysaccharide (EPS) produced by probiotic bacteria whichis Enterococcus faecalis in skin wounds in laboratory animals, and investigate what mechanism EPSs will take to modify the immune response after apply to wounds. The experimental design of this study has several steps as following 100 urine specimen was collected from patients with UTI for isolation and identification E. faecalis followed by extraction and purification EPSs from the obtained bacteria by using ethanol precipitation method and dialysis bag, the concentration of carbohydrate in EPS was estimated according to Dubois method relying on the standard curve of glucose, the four concentration was prepared from purified EPSs (0.125, 0.250, 0,5 and 1 mg/ ml) to evaluate the antibacterial activity against S. aureus in vitro by using agar diffusion method, finally selected the concentration that recorded the highest antibacterial activity for ointment preparation to evaluate the healing ability of the EPSs in vivio, this experiment was included six groups, the animals were anesthetizing by injecting them into the abdominal cavity with Chloral Hydrate 10% (0.35 ml / 100 g) the circle wound (diameter 10 mm) was performed with punch biopsy .Group I: treated with normal Saline daily. Group II: treated with Vaseline only daily. Group III: treated by the ointment only daily. Group IV: the wound was contaminated with S.aureus (by pour 150 ml of bacteria suspension over the wound surface) and after 2 hours the ointment was applied daily. The wound diameter was calculated after 13 day, the immunological parameters of this experiment were included white blood cell count and differential counting, Toll Like Receptor 2 level, interleukin 10, 17 level measured after 7 days of treatment. The result of this study reported 5 % E. faecalis was isolated from the urine specimens and EPS contained 88 % of carbohydrates, on the other hand the concentration (1 mg /ml) showed the highest antibacterial activity. for in vivo study group IV expressed the highest rate of wound healing and highest TLR-2, IL-10 and 17 level with a significant difference at p ≤ 0.05 comparison with other groups, while the total white blood cell account and absolute number was varied between the studied groups. Depending on the obtained results, the current study concluded the purified EPS showed an antibacterial activity potential against S. aureus in different concentrations in vitro study, also purified EPSs from E. faecalis showed a healing ability significantly when used as a topical ointment on the skin wound contaminated with S.aureus which played rule as an immunoregulation by induce 1L-10 production and reduce the inflammatory stage during healing process.