Preparation and characterization of feruloylated oat beta-glucan with antioxidant activity and colon-targeted delivery

Ferulic acid (FA) is an effective chemopreventive and therapeutic agent for colorectal cancer. However, FA cannot stably reach the colon through human digestive system, and it can be grafted into oligosaccharides to improve its digestion stability. Therefore, in this study, different degrees of substitution of feruloylated oat beta-glucan (FA-O beta G) were prepared by grafting FA onto water soluble oat beta-glucan. FA grafting changed the crystallinity and surface morphology of O beta G, and the thermal stability of the FA-O beta G improved. As the DS increased, the antioxidant activity of FA-O beta G increased, and FA-O beta G III with DS of 0.184 showed the same antioxidant activities compared to the equal amount of free FA. The FA-O beta G showed higher stability under gastrointestinal and colonic conditions than free FA. Furthermore, the FA-O beta G conjugates exhibited good in vitro anticancer activity against human colorectal cancer cells, while FA-OG III showed better anticancer activity than an equal amount of free FA.