Study of the therapeutic activity of a probiotic preparation under conditions of dysbiosis

Abstract

An imbalance of the gut microbiota may lead to the development of many chronic diseases; therefore, restoring its normal composition is considered one of the most pressing issues today. Probiotic therapy is being extensively studied as a scientifically validated and safe method for effectively regulating the intestinal biocenosis. In this context, the therapeutic activity of a dry powder form of the studied probiotic preparation was evaluated in an in vivo model of antibiotic-induced gut dysbiosis. White outbred laboratory rats of both sexes, weighing 200–300 g, were used in the study. Fecal samples were collected on days 1, 8, 14, and 18 of the experiment for microbiological analysis of the gut microbiota. Animals were divided into the following groups: control (positive control – saline) and experimental group (probiotic 1×10⁹ CFU/g). For the microbiological analysis of fecal contents, inoculations were performed on eight selective nutrient media. During the dysbiosis phase, the control group showed a significant increase in conditionally pathogenic microorganisms: Clostridium spp. and Salmonella spp. – 9.75±0.31 lg CFU/g, Staphylococcus spp. – 8.13±0.27 lg CFU/g, Enterococcus spp. – 8.58±0.32 lg CFU/g, Klebsiella spp. and Enterobacter spp. – 9.03±0.48 lg CFU/g, and Escherichia coli – 8.46±0.45 lg CFU/g. At the end of the treatment phase, the experimental group showed a notable reduction in these values: Clostridium spp. – 7.91±0.34 lg CFU/g, Staphylococcus spp. – 6.07±0.30 lg CFU/g, Klebsiella spp. – 5.33±0.56 lg CFU/g, E. coli – 6.92±0.44 lg CFU/g. Additionally, the number of beneficial Lactobacillus spp. increased from the initial level of 8.57±0.37 lg CFU/g to 9.00±0.50 lg CFU/g. These findings demonstrate the efficacy of the new lactobacilli-based probiotic in correcting antibiotic-induced intestinal dysbiosis and in restoring microbial balance.