Microbiota changes with fermented kimchi contributed to either the amelioration or rejuvenation of Helicobacter pylori-associated chronic atrophic gastritis

Korean fermented kimchi is probiotic food preventing Helicobacter pylori (H. pylori)-associated atrophic gastritis in both animal and human trial. In order to reveal the effect of fermented kimchi against H. pylori infection, we performed clinical trial to document the changes of fecal microbiota in 32 volunteers (H. pylori (-) chronic superficial gastritis (CSG), H. pylori (+) (5G, and H. pylori (+) chronic atrophic gastritis (CAG) with 10 weeks kimchi. Each amplicon is sequenced on MiSeq of Illumina and the sequence reads were clustered into operational taxonomic units using VSEARCH and the Chao, Simpson, and Shannon Indices. Though significant difference in alpha- or beta-diversity was not seen in three groups, kimchi intake led to significant diversity of fecal microbiome. As results, Klebsiella, Enterococcus, Ruminococcaceae, Streptococcus, Roseburia, and Clostirdiumsensu were significantly increased in H. pylori (+) CAG, while Akkermansia, Citrobacter, and Lactobacillus were significantly decreased in H. pylori (+) CAG. With 10 weeks of kimchi administration, Bifidobacterium, Lactobacillus, and Ruminococcus were significantly increased in H. pylori (+) CAG, whereas Bacteroides, Subdoligranulum, and Eubacterium coprostanolines were significantly decreased in H. pylori (-) CAG. 10 weeks of kimchi intake significantly improved pepsinogen I/II ratio (p<0.01) with significant decreases in interleukin-1 beta. Conclusively, fermented kimchi significantly changed fecal microbiota to mitigate H. pylon-associated atrophic gastritis.