Chemical composition and in vitro antioxidant property of peptides produced from cottonseed meal by solid-state fermentation

In the present study, the cottonseed peptides (CPs) were prepared from cottonseed meal fermented by Bacillus subtilis BJ-1. Chemical composition and antioxidant activities of the CP were investigated. The results showed that the CP contained a balanced ratio of amino acids which dominantly composed of glutamic acid (211.7gkg(-1)), aspartic acid (81.4gkg(-1)), and arginine (97.5gkg(-1)). The molecular weight distribution of CP was lower than 1000Da. The CP presented a concentration-dependent effect on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, hydroxyl radical activity, metal-chelating ability, and reducing power. The half maximal effective concentration values for the DPPH and hydroxyl radicals' scavenging activities, metal-chelating activity, and reducing power were 3.41, 3.28, 1.80, and 1.66mgmL(-1), respectively. Moreover, CP at the lowest concentration of 0.01mgmL(-1) protected the H2O2-induced oxidant death in Raw 264.7 cells. These data suggest that CP could be used as a potential antioxidant for applications in food ingredients.