Comparative evaluation of the antagonistic activity of collection lactobacilli against the multidrug-resistant Klebsiella pneumoniae

Abstract

Taking into account the known data on the high prevalence of multi-drug-resistant Enterobacteriaceae, such as Klebsiella spp., enterohemorrhagic Escherichia coli, and their properties to maintain viability in fermented milk products when using technologies in which, along with starter microorganisms, some enterobacteria with increased resistance to environmental factors (primarily active acidity) can survive and even multiply, the search for new strains of lactic acid probiotic bacteria with a pronounced antimicrobial effect are currently one of the most relevant areas of research in food biotechnology. Representatives of the Lactobacillus genus are currently considered as the most promising objects for the search for producers with probiotic properties. Their antagonistic activity is an important condition for ensuring the biological safety of foods created using fermentation and for developing effective measures to combat conditionally pathogenic and pathogenic microorganisms of the highest priority in terms of epidemiological significance. The aim of the research was to study the antagonistic activity of collectible probiotic Lactobacillus strains in relation to multi-resistant Klebsiella pneumoniae, to assess their suitability in the production of specialized fermented milk products. Material and methods. To determine the antagonistic activity of Lactobacillus collection strains in relation to the Klebsiella pneumoniae strain, two methods were used: co-cultivation and diffusion into agar using wells. Results. As a result of the study of 2 strains of lactic acid bacteria - Lactobacillus helveticus NK1 and Lactobacillus (Lacticaseibacillus rhamnosus) rhamnosus F as antagonists against Klebsiella pneimopiae hospital strain, characterized by multiresistance to antibiotics of different groups, the high efficacy of the L. rhamnosus F. strain was confirmed. Antagonistic activity of the L. helveticus NK1 strain was insignificant, which suggests the variability of Klebsiella and the importance of searching for an antagonist strain with the widest possible spectrum of action. Conclusion. The confirmed high antagonistic activity of the L. rhamnosus F strain makes it possible to recommend it for inclusion in starter cultures. The prospects of using the L. rhamnosus F strain, including for the production of fermented milk products for therapeutic nutrition and other special dietary uses, and for use in the diets of people with dysbiotic disorders, patients with intestinal infections, in particular, caused by multi-resistant strains of Klebsiella pneumoniaе, related to nosocomial infections, are shown. However, further research is needed to determine (identify) the mechanisms of the antimicrobial action of L. rhamnosus F. strain.