Comparative study of components and anti-oxidative effects between sulfated polysaccharide and its iron complex

Sulfated polysaccharide (SP) extracted from sea algae has been used to chelate with ferric to yield polysaccharide iron complex (SPIC). The main active components and groups, monosaccharide composition, molecular weight and anti-oxidative capability were studied comparatively. Results showed that both have good stability and no free ferric ions in SPIC, and no significant difference in total polysaccharide content while sulfate and protein contents lowering and iron content increasing. Fourier-transform infrared (FTIR) spectra indicated further that iron was chelated in polysaccharide chain. Gas chromatograph (GC) showed that the major monosaccharides were fucose, mucose and glucose with molecular ratio of 10:3.8:3.5 in SPIC and 10:8.4:7.5 in SP. MW of SP and SPIC varied no more at 231,3 kD and 237.2 kD respectively using high-performance liquid chromatography (HPLC). Both had hydroxyl radicals scavenging effects in vitro while SPIC showed stronger effects. Comparing oxygen consumption with control PMA-differentiated cells, both took longer time to achieve higher platform and SPIC showed stronger effects than SP. Fluorescence extensity of intracellular ROS showed that SP could reduce the ROS generation while SPIC enhances the effect. The results revealed that the main active components and antioxidant activity exhibit differentiation after SP chelating with ferric.