Novel sorghum brans containing bioactive compounds alter colon microbiota in response to a DSS‐induced chronic inflammatory state

Abstract

We have shown that sorghum brans influence colon injury during inflammation, and bacterial metabolites (e.g., butyrate), suggesting alterations to the microbiota. To determine if the microbiota was altered, rats (n=80) were fed diets containing 6% fiber from cellulose (C), or black (B, 3‐deoxyanthocyanins), sumac (S, condensed tannins), or high tannin black (HT, both) sorghum bran. Inflammation was induced in 40 rats with three exposures to 3% dextran sulfate sodium (DSS), and the microbiota was characterized post DSS by pyrosequencing. There was no difference in bacterial diversity post DSS#2, yet, there were lower Chao species richness in S and HT compared to C and B rats (p<0.05). Post DSS#3 there was an increase in diversity (13.6–25%) and Chao (39–62%) compared to post DSS#2. Post DSS#3, C and B DSS rats had a lower and S and HT DSS rats had a higher Chao compared to controls (p<0.05). Post DSS#3, the proportion in the Clostridiales order was reduced (56%–79%) relative to post DSS#2, and there were diet effects post DSS#2 and #3 for bacteria in the Bacteroidales (both p<0.0001) and Clostridiales orders (p<0.0001 and p=0.039). The data indicate the microbiota is affected by DSS and polyphenol‐rich sorghum brans, which influence species richness and diversity. Thus, these sorghum brans may protect against reduced microbial diversity and richness typically observed in chronic inflammation. Funded by USCP Roo31A‐09.Grant Funding Source: USCP Roo31A‐09