Abstract: This study aimed to investigate the effects of exopolysaccharides from Bacillus amyloliquefaciens JN4 (EPS-JN4) on the propagation and metabolism of probiotics. The specific proliferative effects of EPS-JN4 were analyzed by PCR-denaturing gradient gel electrophoresis, and their effects on the growth, metabolites, intestinal tolerance, and surface hydrophobicity of lactic acid bacteria were also determined. It was found that EPS-JN4 had a specific proliferative effect on Lactobacillus reuteri. Compared to glucose, the early proliferation rate of L. reuteri JN125 treated with EPS-JN4 was slower, but its highest biomass was 4.25 times higher. In addition, the contents of lactic acid and acetic acid reduced by 12.2% and 32.4%, respectively. The intestinal tolerance and surface hydrophobicity of EPS-JN4-treated L. reuteri JN125 significantly improved, which could be due to the protein and lipid contents in cell membranes increased by 40.8% and 105.7%, respectively. Besides, the proportions of 18 C fatty acids and unsaturated fatty acids in cell membranes significantly increased. In conclusion, EPS-JN4 can be used as a potential prebiotic to regulate the intestinal health of animals.
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