Probiotic strain Lactobacillus reuteri: selection of the technological regimes for cultivation

The characteristics of the new probiotic Lactobacillus reuteri strain being one of the few autoxtotic lactobacillus types typical for people are presented in the article. The strain was selected in VNIMI СєпЬді Laboratory of Microbiology. The prospects of its usage for the production of fermented dairy products with probiotic properties has been described. The composition of the nutrient medium developed earlier for its cultivation is presented.The aim of the work is the investigation of the dynamics of Lactobacillus reuteri growing in the enzyme at different pH and temperature index and determination of optimal meanings providing intensive accumulation of living and active cells. The intervals of active acidity values pH 5,6; 5,8; 6,0; 6,2; 6,4; 6,6 units and temperature -32, 35, 37, 39, 41 °С have been investigated within the working process. The inoculate was prepared in MRS media and in all experiments was introduced in the amount of 5 %. The amount of Lactobacillus reuteri in GMK -1 medium and cultivation of inoculations in anaerobic conditions were determined at 37 °С within 3-5 days. The obtained results showed that the largest amount of Lactobacillus reuteri cells was achieved at strains cultivation at pH 5,8-6,2 units. Thus at maintaining of pH at the level of 5,8 pH units the number of cells made up 9,18 lg CFU/cm 3 but at pH 6,2-9,15 lg CFU/cm 3. The investigation of the influence of cultivation temperature at Lactobacillus reuteri cells accumulation showed that cultivation temperature 35 °С and 37 °С - the most dynamics and quick cells growth was observed. At 35 °С the largest cells number 9,14 lg CFU/ cm 3 was achieved after 8 hours cultivation and at 37 °С the cells number was at the level of 9,18 lg CFU /cm 3 С. The higher cultivation temperatures 39 and 41 °С and lower 32 °С influenced negatively the cells accumulation in the nutrient medium.

Lactobacillus reuteri, probiotic microorganisms, Lactobacillus reuteri, biotechnology, operating practices, bacterial concentrate