Effects of Rubus coreanus byproducts on intestinal microbiota and the immune modulation

Although the efficacy of (RC) byproducts as a feed additive has been recognized, its effects on intestinal microorganisms and the immune system are still unknown. Six-week-old male rats were treated with 0.5% RC (T1), 1.0% RC (T2), and 1.5% RC (T3) for 4 weeks. We found that treatment with RC byproducts significantly increased the daily gain of body weight and feed intake. Treg-cell differentiation was enhanced in the mesenteric lymph nodes and spleen from the rats fed with RC byproducts. Illumina sequencing showed that bacteria in the phylum decreased and while those in the phylum increased in RC-treated groups. Particularly, the pathogenic microorganisms in the family decreased, and the non-pathogenic families and increased. Quantitative polymerase chain reaction analysis showed that the RC byproducts increased the lactic acid bacteria spp., spp., , and in a concentration-dependent manner. RC byproducts may be effective in immunomodulation by affecting intestinal microorganisms.