Studies on molecular modification and biological activity of one seaweed polysaccharide

BIOL 159

Wenjun Mao, wenjunmqd@hotmail.com and Xiaoxue Zang. Marine Drugs and Foods Institute, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
Seaweed polysaccharide is a complex mixture of linear polysaccharides that display a wide array of biological activities. One of the seaweed polysaccharides of interest in our laboratory is agar. Agar is a polysaccharide extracted from certain marine red algae and mainly consisted of an alternating β- (1→3) D-galatopyranose and 4-linked 3, 6-anhydro-L-galatopyranose units. It is used as additives to improve food texture, gelation, stability, and viscosity and are generally regarded as safe. Applications of agar in some ways are restricted by its higher molecular weight. In the paper, the agar-derived oligosaccharides were prepared by agarase from microorganism and chemical methods. The oligosaccharides were purified by ion-exchange and size-exclusion column chromatography, and the structural characterizations of the oligosaccharides were determined using various spectroscopic methods. The antioxidative activity and radioprotective effect of the oligosaccharides are currently being investigated.