L. plantarum P8 was isolated from traditionally fermented sour milk samples collected from herdsmen in Wulatezhongqi grassland, Bayannaoer, Inner Mongolia, China. L. plantarum P8 was selected as it was the best among 347 other Lactobacillus strains with excellent tolerance to gastric acid, intestinal fluid and bile salt of the digestive system. P8 is incorporated and sold in the market of China, Taiwan and Singapore in a variety of products, ranging from dairy (yoghurt and fermented milk), health supplements to pet foods. P8 is patented in China and also awarded by the Chinese government as a functional probiotic. Two human clinical trials have shown that the administration of P8 at a concentration of 10 log CFU/day for 4-weeks, improved gastrointestinal health of adults subjects via increasing the population of beneficial gut microbiota accompanied by decreasing gut opportunistic pathogens, increasing fecal levels of secretory immunoglobulin-A and short chain fatty acids.