PHÂN LẬP, ĐỊNH DANH VÀ ĐÁNH GIÁ TIỀM NĂNG PROBIOTICS CỦA MỘT SỐ CHỦNG NẤM MEN SACCHAROMYCES CEREVISIAE TỪ CHẤT CHỨA TRONG RUỘT GÀ

Abstract

The study was carried out to isolate, identify Saccharomyces cerevisiae from the digestive tract of chicken and evaluate the appropriateness for use as a probiotic. A total of 32 yeast strains were isolated from the 52 digestive tracts of chicken samples. The yeast strains were isolated using yeast peptone dextrose agar medium and identified through morphological, physiological, and biochemical tests as well as sequence homology analyses of the ITS region. Three strains Y35, Y63, and Y100 were obtained and have been identified as Saccharomyces cerevisiae species. The strains were further screened so that they could be used as probiotic strains added to animal feed. The strains have been evaluated for some properties: resistance to high temperature (30^oC, 37^oC, 42^oC, 50^oC), to low pH (2.0; 3.0 and 4.0) and bile salts (0.1%, 0.2%, and 0.3%). The results showed that among the three strains (Y35, Y63, Y100), the Y35, and Y100 strains had higher biomass, tolerance to high temperature (42^oC), low pH (2), and bile salts (0.3%). So, the strains Y35 and Y100 can be used for further studies to evaluate other criteria for probiotics production as animal feed additives.