Corn Bran IDF and Polyphenol-Reduced IDF Alleviate Low-Dose 3-MCPD-Induced Toxicity by Modulating Gut Microbiota and Intestinal Barrier.

The polyphenols in insoluble dietary fiber (IDF) alleviate the toxicity of 3-chloro-1,2-propanediol (3-MCPD); however, the effect of polyphenol-reduced IDF on 3-MCPD toxicity remains unclear. This study compared the effects of IDF and IDF modified with alkaline hydrogen peroxide (IDF-AHP) on alleviating the toxicity of low-dose 3-MCPD in mice. The results indicate that both IDF and IDF-AHP retained their polysaccharide structures; however, the polyphenol content and antioxidant activity of IDF-AHP were significantly reduced. Both fibers alleviated 3-MCPD-induced motor impairments. Histological studies revealed that both dietary fibers reduced inflammatory cell infiltration in the colon, decreased serum diamine oxidase (DAO) levels, and enhanced intestinal barrier function. 16S rRNA sequencing results indicated that the two dietary fibers did not affect the abundance or uniformity of the microbiota within individual samples but did cause differences in the microbial composition between samples. Alistipes and Bacteroides (IDF + 3-MCPD group vs. 3-MCPD group) and Mucispirillum (IDF-AHP + 3-MCPD group vs. 3-MCPD group) may mediate the effects of IDF and IDF-AHP in alleviating motor impairment induced by low-dose 3-MCPD. These findings suggest that the attenuation of low-dose 3-MCPD toxicity by IDF and polyphenol-reduced IDF may be related to the modulation of gut barrier function and the abundance of gut microbiota. They have potential as food additives and hold promise for further development as functional foods.