Feruloyl oligosaccharides, isolated from bacterial fermented wheat bran, exhibit antioxidant effects in IPEC‐J2 cells and zebrafish model

Feruloyl oligosaccharides (FOs) were produced by solid‐state fermentation of wheat bran using Bacillus subtilis, Bacillus licheniformis, and Saccharomyces cerevisiae, and its antioxidant activity was investigated using IPEC‐J2 cells and zebrafish embryo model. Preliminary structure analysis revealed that FOs has an average molecular weight of 11.81 kDa and consists of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose, and fucose. The obtained FOs possess superior reducing power and DPPH and hydroxyl free radical scavenging activities. In IPEC‐J2 cells, antioxidant enzymes activities and GSH level were significantly increased, while MDA level was reduced by FOs. Further studies showed that FOs achieved the aforementioned effects by activating Nrf2 signaling pathway. In zebrafish embryo, FOs effectively suppressed ROS production, lipid peroxidation, and cell death by increasing SOD and GSH‐Px activities. Our findings suggested that FOs from solid‐state fermented wheat bran with mixed bacteria can be used as an antioxidant food additive or drugs.