Antibiotics that prevent endotoxemia do not reduce the ability to ferment high amylose maize resistant start (HAMRS2) in rats (1044.11)

Abstract

The gut microbiota affects health. Research with antibiotics (ampicillin 1 g/L, and neomycin 0.5 g/L in drinking water) reduced bacterial DNA and endotoxemia in mice fed high fat diet or ob/ob mice fed chow. The antibiotics reduced Lactobacillus, Bifidobacterium, and Bacteroides spp. Several of these ferment HAMRS2. We tested if these antibiotics prevented fermentation of HAMRS2 in rats. Phase 1 consisted of feeding two groups of rats with either HAMRS2 diet without antibiotics (n=10) or a diet with no fermentable carbohydrates with antibiotics (n=19). After 3.5 weeks, 5 rats from each group were euthanized for cecal content pH and short chain fatty acid (SCFA) analysis. An additional 5 rats on the HAMRS2 diet were euthanized where their cecal contents were pooled. The cecal pH was significantly lower (p<0.05) for the group fed HAMRS2 while the other group produced very low SCFA. The remaining rats (14), fed with antibiotics and no HAMRS2 were split into two groups, one of which was gavaged with the previously pooled cecal contents (n=7) while the others were gavaged with water (n=7). Thereafter both groups were fed HAMRS2 diet for 3.5 weeks. After the second phase, cecal content analysis indicated both groups fermented HAMRS2 while pH and production of SCFA were not different. Our results suggest antibiotics used to control metabolic endotoxemia do not alter HAMRS2 induced fermentation.Grant Funding Source: Supported by Ingredion, Inc. and LSU AgCenter