Screening and Characterization of the Antagonistic Properties of Microorganisms Isolated From Natural Sources

BACKGROUND: Human infectious diseases caused by antibiotic-resistant bacterial pathogens present a serious problem for clinical medicine. Causative agents of nosocomial infections, such as Escherichia coli, Klebsiella pneumoniae, Enterobacter spp., are the most common among them. An active search for antimicrobial agents that can effectively combat drugresistant pathogens is underway. Antimicrobial substances of bacterial origin are of particular interest. Promising sources of microorganisms with antibiotic properties are natural sources: Soil, water, plants, etc. AIM: The purpose of this work is to screen and characterize the antagonistic properties of microorganisms isolated from natural sources in connection with the creation of new pharmaceutical substances. METHODS: The material for the isolation of microorganisms was the soil, water bodies, and plant objects of various municipal districts of the Kemerovo Region. Identification of the isolated microorganisms was carried out using the methods proposed in the directory “Bergey’s Manual of Determinative Bacteriology” and in the monograph Nesterenko et al. The selection of strains from soil samples was carried out according to standard methods described in “Methods of soil microbiological control. Methodical recommendations,” cultural-morphological properties of isolates were studied using conventional microbiological methods. RESULTS: The following results are obtained: (1) Lactic acid bacteria and other microorganisms antagonists from natural sources were isolated: Soil, water bodies, and plant objects; 20 isolates were isolated, their cultural and morphological properties were studied; isolated microorganisms were found to belong presumably to the genera Bacillus, Leuconostoc, Pedio-coccus, Lactobacillus, and Bacteroides; (2) Antimicrobial properties of lactic acid bacteria and other antagonistic microorganisms isolated from natural sources on solid and liquid nutrient media were studied; (3) 12 strains of 20 isolates with maximum antimicrobial properties were selected for further studies. CONCLUSION: Further research on the biochemical properties of lactic acid bacteria and other antagonist microorganisms isolated from natural sources, the study of antibiotic resistance of lactic acid bacteria and other antagonist microorganisms isolated from natural sources, as well as other more detailed studies will be conducted with selected 12 strains with maximum antimicrobial properties

Determination of the antibacterial activity of flavonoids from callus Scutellaria galericulata L. for the development of a functional curd product

The antimicrobial effect of extracts from callus of the common skullcap with the prospect of using in the recipe of a functional curd product for therapeutic and preventive action is studied. It is known that plants of the genus skullcap contain phenolic compounds that cause antimicrobial action, the most common among them are flavonoids-baykalin, scutellarein, hydrolyzed to glucuronic acid and aglycones-baykalein and scutellarein, vogonin, etc. the Study of antimicrobial activity was carried out in accordance with the requirements of The state Pharmacopoeia XI edition. Antimicrobial activity was determined in relation to 15 test cultures by diffusion in agar. The method is based on the assessment of inhibition of growth of test cultures of microorganisms by certain concentrations of the test object. Rod-shaped bacteria (Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Serracia marcescens, Escherichia coli, Morganella morganii, Hafnia alvei, Bacillus cereus), coccus microflora (Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecium), different strains of fungi of the genus Candida (Candida non-albicans № 136, 138, 142, 144). The result was evaluated according to the following criteria: “-“ – growth of the test culture (there is no antibacterial effect); “+” – no growth (the antibacterial effect is pronounced); “±” – inhibition of growth (bacteriostatic action)