Goat milk fermented with combined lactic acid bacterium alter microbial community structures and levels of the targeted short-chain fatty acids in the large intestine of mice

The present study investigated effects of the fermented goat milk (FGM) produced with a combination of Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus (SL) and with another one of SL as well as Bifidobacterium animalis subsp. lactis (SLB) on the internal environment in the large intestine of mice. Both the richness and the diversity of microbiota was the most abundant in SL group. SL, SLB and the control groups were clustered into three independent groups. At the phylum level, Firmicutes was the most abundant in all the groups, and Deferribacteres in SLB group was more abundant than in SL group. SL and SLB increased the proportions of 6 and 5 genera, respectively. Firmicutes was positively correlated with all the significantly different species but negative to Actinobacteria at the phylum level. SL and SLB both significantly decreased the levels of butyric and valeric acids. Either SL or SLB can significantly improve the structures of microbiota, and both of them significantly decreased the levels of butyric and valeric acids in the large intestine of mice. Certain microbiota negatively related to the levels of butyric and valeric acids. FGM produced with SL or SLB can effectively alter the microbial flora and the levels of SCFA in the large intestine of mice.