Production of agar-derived antioxidants and Single cell detritus from Gracilaria corticata using agarase from Microbulbifer sp. CMC-5

Abstract

Microbulbifer strain CMC-5 reportedly degrades multiple polysaccharides including agar. In present study, the agarase from the culture supernatant of Microbulbifer strain CMC-5 pregrown in artificial sea water-based medium containing agar was tenfold concentrated by ultrafiltration. The bacteriological agar-derived oligosaccharides obtained by agarase treatment were observed to depict reducing power, lipid peroxidation inhibition and hydroxyl radical scavenging activities. The oligosaccharides produced from agar by agarase treatment for 6 h demonstrated higher antioxidative activities as compared to agar oligosaccharides produced by 12-h agarase treatment. Further, the agar oligosaccharides demonstrated concentration-dependent augmentation of antioxidative activities. Since agar is a recognized safe food additive, the agar-derived oligosaccharides can be blended with food to augment its antioxidative property. Additionally, the agarase from strain CMC-5 in conjunction with Onozuka R-10 degraded Gracilaria corticata thalli to produce single cell detritus that can be used as aquaculture feed material reducing the dependency on artificial feeds.