Producing metabolic complexes of probiotic microorganisms with significant antimicrobial properties

Abstract

The aim of the work – to produce metabolic complexes with significant antibacterial properties using a new proprietary method and to substantiate the prospects of their use for designing of antimicrobial polyfunctional drugs. Materials and methods. Metabolic complexes of Lactobacillus rhamnosus GG, Lactobacillus plantarum, Saccharomyces boulardii, Enterococcus faecium were obtained by culturing the producers in ultrasonic disintegrates of other probiotic microorganisms. Sensitivity of antibiotic-resistant strains of Escherichia coli PR and Staphylococcus haemolyticus PR was determined by qualitative method. The suspension of test-cultures (optical density of 1.0 units on the McFarland scale) after incubation with metabolites (2, 24 and 48 hours at 37 °C) was inoculated into Mueller–Hinton agar. The absence of growth was indicative of the metabolic complexes antibacterial activity against the microorganism. Results. Cultivation of S. boulardii in the S. boulardii / L. rhamnosus / L. plantarum / E. faecium disintegrates, L. plantarum – in the L. rhamnosus / E. faecium disintegrates and L. rhamnosus – in the L. plantarum disintegrates was accompanied by an increase in the biomass of isolated microorganisms (P ≤ 0.03) and production of metabolites. Along with a similar increase in S. boulardii cells in the S. boulardii / L. rhamnosus / L. plantarum / E. faecium disintegrates, the metabolic products of lactobacterial and enterococcal disintegrates exhibited more active inhibitory effects against E. coli PR and S. haemolyticus PR. The increased antibacterial activity indicates the advantage of the new method. Another improvement is the extended spectrum of metabolic complexes owing to producer cultivation in the other probiotic disintegrates to obtain original biologically active substances with high antibacterial properties against pathogens. Among the strength of the method is that all the stages are unified into a single process avoiding multiphase procedure for the separate preparation of one probiotic microorganism disintegrate and the metabolic products of another. Conclusions. Disintegrates as a nutrient medium can be used not only for their own producers, but also for other strains/species and various probiotic microorganisms (fungi and bacteria). The increase in antibacterial activity of metabolic complexes has been found using the new method of production. The prospects of antimicrobial polyfunctional drugs designing on this basis have been proved.