Aaron Yerke, Pei Wang and Shengmin Sang (2016). Microbial-derived metabolites of oat avenanthramides. The FASEB Journal, 30(1).
North Carolina A&T State University, Kannapolis, NC
Oat is a multifunctional crop nutritionally superior to many other unfortified cereals. It is commonly consumed as whole grains and known to provide healthy nutrients to humans. Oats contain a unique type of compounds, avenanthramides (AVAs), which are a group of substituted N-cinnamoylanthranilic acids. They are all composed of an anthranilic acid part and a cinnamic acid part, where the substitution pattern on the two parts is what distinguishes the different AVAs from each other. AVAs have been reported to have anti-oxidative, anti-inflammatory, anti-itching, and anti-cancer activities. However, the biotransformation of AVAs is still largely unknown. We recently studied the biotransformation of the three major AVAs in mice and by human gut microbiota. Our results indicated that reduction of the double bond in the cinnamic acid unit and the cleavage of the amide bond are the major metabolic pathways of AVAs in mice and by human gut microbiota. Further mechanistic studies demonstrated that the AVAs are mainly metabolized by gut microbiota instead of liver and intestinal microsome and S9. In addition, we also observed inter-individual variations on the metabolism of AVAs by human gut microbiota.