Studies On Isolation And Characteristics Of A Probiotics Bacterium Identified As Bacillus Coagulans

Bacillus coagulans not noly have the ordinary lactic acid bacteria effects that can maintain intestinal microflora balance, stimulate immunity, improve the body’s health, improve human and animal digestive function, but aslo they have the unique biological properties like strong environmental resistance, anti-acid, anti-drying, autoclavable and easy storage.In this study, a live bacillus strains were screened from chicken intestinal contents and bacillus laboratory has purified. Morphological, biochemical and physiological, and phylogenetic analyses of the16s rRNA sequence showed that C8belonged to Bacillus. C8had the closest relationship with Bacillus coagulans among all reported strains. Thus, it was identified as Bacillus coagulans C8. We Systematically probe into the related characteristics, such as the restrain to harmful pathogenic bacteria, tolerance to simulated gastric juice and bile salts and so on.After processed with simulated gastric juice of pH=2, the survival rate is20.9%. In0.3%concentration of bile salt medium for24h, the survival rate is21.8%. After heat treatment of80℃for30min, the number of living bacterium only decreased by one order of magnitude. Bacteriostatic experiment shows that there are inhibitory effect on escherichia coli, staphylococcus aureus. C8can produce amylase, protease of promoting animal intestinal digestion and absorption function. Most common antibiotics can inhibit the growth of the strain that has only good compatibility with cefixime. Based on the research of the fermentation culture medium composition, C8number of living strain can reach the highest with40g/L in the concentration of starch as carbon source and40g/L yeast extract as nitrogen source. Determined by the optimization of fermentation conditions, the best fermentation conditions of strains C8were determined.