"Formation of Hydrogels From Antioxidative Synthetic Hydroxycinnamate Ester Conjugates Based on Corn Bran Arabinoxylan "

Corn bran arabinoxylan (CAX) was extracted from corn bran and modified through conjugating to four hydroxycinnamic acids (HAs), namely ferulic acid (FA), p-coumaric acid (p-CA), caffeic acid (CA), and sinapic acid (SA). These HA arabinoxylan esters (HA-CAX-n) exhibited analogous n-degrees of substitution (DS), FA-CAX-0.31, p-CA-CAX-0.32, CA-CAX-0.32, and SA-CAX-0.31. The antioxidant capacity was evaluated by a chemical method – an oxygen radical antioxidant capacity (ORAC) assay – and cellular models – a cellular antioxidant activity (CAA) assay to healthy human skin fibroblasts (HSF). The results of the various analyses were comparable, demonstrating the order of antioxidant capability was: CA-CAX-0.32 > SA-CAX-0.31 > FA-CAX-0.31 > p-CA-CAX-0.32. HA-CAX-n gels with different crosslinking ability were obtained with the concentration of 0.5% (w/v) during oxidative gelation by laccase, SA-CAX-0.31 can form gels most easily, followed by FA-CAX-0.31, CA-CAX-0.32 and p-CA-CAX-0.32.