The method for preparing low molecular weight fucosylated chondroitin sulfate from sea cucumber Isostichopus badionotus using partial acid hydrolysis was reported, and its hydrolysis mechanism was also investigated. The sea cucumber chondroitin sulfate FCS was hydrolyzed under different conditions (80 ℃ 3 h and 6 h), then isolated and purified on a Bio-P-4 geltration to prepare low molecular weight fractions (LMWF-FCS). The chemical compositions of LMWF-FCS showed the branched fucose (Fuc) was cleaved during acid hydrolysis process, whereas the mole ratio of acetyl-galactosamine (GalNAc) and glucuronic acid (GlcA) in the backbone remained the same, which indicated the backbone was a typical chondroitin sulfate structure. The disaccharide composition analysis of LMWF-FCS suggested that the sulfation patterns of GalNAc in the backbone chain changed and the substitution value was reduced. Furthermore, the 1 D NMR analysis illustrated the branched-Fuc was cleaved during acid hydrolysis, but their substitution patterns were not influenced, which was distinct from the previous reports that the substitutions of branched-Fuc in FCS were easy to change. Simultaneously, the sulfation pattern of GalNAc in backbone chain changed obviously in the acid hydrolysis process. The anticoagulant activity in vitro illuminated the anticoagulant activity of the degradation products over time in the acid hydrolysis are gradually declined, but still kept good. Therefore, the LMWF-FCS prepared could be developed as a new anticoagulant and antithrombotic drug like low molecular weight heparin.
Gelatin extracted from the body wall of the sea cucumber (Stichopus japonicus) was hydrolyzed with flavourzyme.Low-molecular-weight gelatin hydrolysate (LMW-GH) of 700-1700 Da was produced using an ultrafiltration membrane bioreactor system.Chemiluminescence analysis revealed that LMW-GH scavenges high free radicals in a concentration-dependent manner;IC50 value for superoxide and hydroxyl radicals was 442 and 285 μg mL-1,respectively.LMW-GH exhibited excellent inhibitory characteristics against melanin synthesis and tyrosinase activity in B16 cells.Furthermore,LMW-GH notably increased intracellular glutathione (GSH),which in turn suppressed melanogenesis.LMW-GH performs antioxidation activity,holding the potential of being used as a valuable ingredient in function foods,cosmetics and pharmaceuticals or nutriceuticals.
WANG Jingfeng WANG Yuming TANG Qingjuan WANG Yi CHANG Yaoguang ZHAO Qin XUE Changhu
