Evaluation of resistance of isolated soil strains of <i>Bacillus subtilis</i> to antibacterial drugs on the example of amoxicillin and ceftriaxone

Abstract

Relevance. In agriculture, transient probiotic strains from the Bacillus spp. group have recently been widely used. The high antagonistic potential and resistance to abiotic factors, due to the ability to spore formation of representatives of this genus of microorganisms, makes them the most promising agents for inclusion in feed probiotics. In this regard, the purpose of our work is to investigate the biological potential of tolerance of B. subtilis soil isolates to antibacterial drugs on the example of amoxicillin and ceftriaxone.Methods. To achieve this goal, we have selected soil samples from territories with a high level of anthropogenic agricultural load. Sampling was carried out at 5 points of the site we determined from a depth of more than 40 cm. Bacillus subtilis strains were used as biological objects in the work. Further work was related to the isolation of isolated strains of Bacillus subtilis bacteria, for which we used: the method of serial breeding, lawn sowing on dense nutrient media, isolation of pure cultures and identification of microorganisms by cultural characteristics of growth on dense media and color by Gram.Results. Preliminary results of a study of antibiotic resistance of representatives of one species of B. Subtillis isolated from one soil sample, but having different levels of resistance to the tested antibiotics (resistants), are presented. In the course of the conducted studies, a general pattern of sensitivity of the studied strains to ceftriaxone and heterogeneously distributed indicators of resistance to amoxicillin were established.