AUTHOR=Shen Jiakun , Zhang Jie , Zhao Ying , Lin Zishen , Ji Linbao , Ma Xi 

TITLE=Tibetan Pig-Derived Probiotic Lactobacillus amylovorus SLZX20-1 Improved Intestinal Function via Producing Enzymes and Regulating Intestinal Microflora

JOURNAL=Frontiers in Nutrition

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2022.846991

DOI=10.3389/fnut.2022.846991

ISSN=2296-861X

ABSTRACT=<p>The interaction between exogenous microorganisms and the host has received great attention, and finding new probiotics is always the way to improve the health of humans and animals. <italic>Lactobacillus amylovorus</italic> (<italic>L. amylovorus</italic>) is a kind of <italic>Lactobacillus</italic> that can efficiently utilize starch, as a food and feed additive, it has been widely used for mildew prevention and antibacterial, bacteriostasis, and enzyme production. Herein, a strain of <italic>L. amylovorus</italic> was isolated from the feces of Tibetan weaned piglets, named <italic>L. amylovorus</italic> SLZX20-1. Physiological and biochemical experiments <italic>in vitro</italic> confirmed that it had a fast growth rate and could produce a variety of enzymes, including α-galactosidase, β-galactosidase, α-glucosidase, β-glucosidase, and ferulic acid esterase. In addition, <italic>L. amylovorus</italic> SLZX20-1 exerted antibiotic effects on the growth of <italic>Salmonella typhimurium</italic> (<italic>S. typhimurium</italic>) SL1344, <italic>Citrobacter rodentium</italic> (<italic>C. rodentium</italic>) DBS100, <italic>Salmonella pullorum</italic> (<italic>S. pullorum</italic>) CVCC1791, <italic>Staphylococcus aureus</italic> (<italic>S. aureus</italic>) CVCC1882, <italic>Escherichia coli</italic> (<italic>E. coli</italic>) O157, <italic>E. coli</italic> K88, <italic>E. coli</italic> K99, and <italic>E. coli</italic> 987P, which are closely related to acid productivity, such as lactic acid and acetic acid. <italic>In vitro</italic> co-culture, <italic>L. amylovorus</italic> SLZX20-1 has shown the strong adhesion ability to intestinal porcine epithelial cells (IPEC-J2 cells) and activated IPEC-J2 cells with high expression of host defense peptides (HDPs), such as <italic>NK-Lysin, PEP2C</italic>, and <italic>PBD-1</italic>. <italic>In vivo</italic> experiment, <italic>via</italic> intragastric administration, <italic>L. amylovorus</italic> SLZX20-1 significantly improved the feed intake of mice, declined the crypt depth of jejunum and ileum, <italic>L. amylovorus</italic> SLZX20-1 changed the composition of intestinal microbes, especially at the level of colonic genus, the dominant genus was changed from <italic>Lactobacillus</italic> to <italic>S24-7</italic>, which indicated the change of intestinal carbohydrate nutrition. In conclusion, <italic>L. amylovorus</italic> SLZX20-1 showed strong probiotic characteristics, which met with the standard of probiotics and is worth further exploring its impacts on host health and its potential as a candidate strain of probiotics.</p>