Influence of the composition of the culture medium on the growth and sporulation of the probiotic strain Bacillus amyloliquefaciens M

Abstract

Bacillus amyloliquefaciens M is a non-pathogenic microorganism with probiotic properties isolated from mineral waters in the village of Yabаlkovo, Haskovo region, for inclusion in the composition of probiotics and probiotic foods. It has high antimicrobial activity against pathogenic bacteria, causing food toxic infections and intoxications, as well as against saprophytic microorganisms - bacteria and fungi, which makes it suitable as a biological preparation for plant protection. In order to perform these functions, it is necessary to obtain a spore concentrate. The composition of the nutrient medium for the cultivation and sporulation of the strain has been determined: MP nutrient broth with the addition of salts, in which the strain grew well and a high sporulation rate of 99% was achieved. Cultivation in a bioreactor has been carried out and the time to achieve a high degree of sporulation has been determined. The kinetic parameters of growth and sporulation of Bacillus amyloliquefaciens M in aerobic batch cultivation with a high concentration of spore forms have also been determined. It has been shown that the sporulation process in this strain starts after 12 h from the cultivation start.