Development of a liquid nutrient medium for cultivation of a probiotic strain of the bacterium Bacillus subtilis TNP-3

The aim of the work is to search for components of nutrient media for the cultivation of Bacillus subtilis as the basis for ensuring a waste-free technology for obtaining a feed additive. The article presents data on the cultivation of the bacterium strain Bacillus subtilis TNP-3 on grain nutrient media having the following composition:1) 3 % decoction from spring wheat seeds with the addition of 1 % CaCO3; 2) 3 % decoction from spring wheat seeds with the addition of 1 % zeolite from the Khongurinsky deposit. The obtained samples of nutrient media have a pleasant wheat smell and a yellowish color. During experiments when cultivating strains of the bacterium B. subtilis TNP-3 in a thermostat at a temperature of 37 °C, both on experimental nutrient media and on BCH (control), the same growth was observed without turbidity, with the formation of a film on the surface and its precipitation during shaking, which is typical for aerobic spore-forming bacteria. The maximum number of B. subtilis TNP-3 bacterial strain is achieved on a nutrient medium based on 3 % decoction of wheat with the addition of 1% zeolite for 72 hours of growth, up to 181±2.0 CFU*109/ml and exceeds the growth in the control (BCH) in CFU/ml by 43 %. In all samples of nutrient media, the pH value is neutral, optimal for the cultivation of microorganisms. Thus, the obtained research results allow us to conclude that a medium based on 3 % wheat broth with the addition of 1 % zeolite – Hongurin is suitable for the cultivation of a probiotic strain of B. subtilis TNP-3 bacteria and is promising in the development of a waste-free technology for obtaining a feed additive for farm animals.