Mingxing Zhao

Sulfation, anticoagulant and antioxidant activities of polysaccharide from green algae Enteromorpha linza.

Sulfated polysaccharides exerted potent biological property which was relative to degree of sulfation, molecular weight, substitution position and chain conformation. In present study, the polysaccharide with low molecular weight (LEP) from Enteromorpha linza was sulfated with chlorosulfuric acid in formamide. The obtained polysaccharide sulfate was selected to evaluate their antioxidant activities and the anticoagulant activity in the coagulation assays, activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT). The data obtained in vitro models indicated that high DS and moderate Mw showed the best anticoagulant and antioxidant activities.

Synthesized oversulfated and acetylated derivatives of polysaccharide extracted from Enteromorpha linza and their potential antioxidant activity.

Sulfated polysaccharide extracted from blue algae Enteromorpha linza is proved to possess excellent antioxidant activities. Two derivatives by means of oversulfated and acetylated coupling were synthesized and investigated their antioxidant activities including scavenging effect of superoxide, hydroxyl and 1,1-diphenyl-2-picrylhydrazyl radicals. And then the relationship between antioxidant activity and chemical characteristics was characterized. The results of chemical analysis and FT-IR showed that the modification of polysaccharide was successful. In addition, it was found that certain derivatives exhibited stronger antioxidant activity than raw material. They could serve as free-radical inhibitors or scavengers, acting possibly as primary antioxidants.

Phosphorylation of low-molecular-weight polysaccharide from Enteromorpha linza with antioxidant activity.

In this study, the phosphorylated derivative of low-molecular-weight polysaccharide from Enteromorpha linza was prepared. And then the antioxidant activities of all the samples were investigated including scavenging effects of superoxide and hydroxyl radicals and reducing power. The results of chemical composition, FT-IR spectrum and DSC analysis showed the modifications of polysaccharide were successful. And moreover, the phosphorylated derivative showed excellent antioxidant activity in these three assays, so this derivative needs to be attention in further.

Carboxymethylation of polysaccharides from Tremella fuciformis for antioxidant and moisture-preserving activities.

The carboxymethylated polysaccharide (CATP), which derived from water-insoluble crude Tremella fuciformis polysaccharide (ATP), was prepared. And then the antioxidant and moisture-preserving activities of the samples were investigated. The results of chemical composition and FT-IR analysis showed the carboxymethylated modifications of polysaccharide were successful. The degree of substitution (DS) of four carboxymethylated derivatives were different with the molar of monochloroacetic acid. Their water solubility and biological activities were improved with the increase of DS. And moreover, a high antioxidant and moisture-preserving activities of CATPs was observed, so this derivative needs to be attention and studied in further. Results proved that the carboxymethylation could effectively enhance their potential biological properties of the polysaccharide.

Free-radical degradation by Fe2+/Vc/H2O2 and antioxidant activity of polysaccharide from Tremella fuciformis

The free-radical degradation and antioxidant activity of polysaccharide from Tremella fuciformis was investigated. In present study, the combination of Fe(2+), ascorbic acid and H2O2 was used as degradation regents in order to obtain the lower molecular weight product. The result ascertained oxidative-reduce degradation did not change the main structure of polysaccharides in the test conditions. Five degraded polysaccharides were selected to evaluate their antioxidant activities in vitro. It was found that the degraded sample with lower molecular weight possessed the higher antioxidant activities. It was possible that free-radical degradation is an effective way for enhancing antioxidant activity to decrease molecular weight of polysaccharides.

The immunological and antioxidant activities of polysaccharides extracted from Enteromorpha linza

Polysaccharides extracted with water and alkali from Enteromorpha linza were a group of hetero polysaccharides, and their immunological and antioxidant activities were investigated employing various established in vitro systems. The structural analysis showed that they were composed of rhamnose, mannose, xylose, glucose, and galactose with different molar ratio. Available data obtained with in vitro models suggested that the two kinds of polysaccharide showed significant inhibitory effects on radical and could increase the capability of T and B lymphocytes proliferation. These results clearly establish the possibility that these polysaccharides extracted from E. linza could be effectively employed as ingredient in health or functional food, to all eviate oxidative stress. However, comprehensive studies need to be conducted in experimental animal models.

Physicochemical properties and inhibition effect on iron deficiency anemia of a novel polysaccharide-iron complex (LPPC).

Porphyran (P) was extracted from red algae Porphyra by boiling water. A novel polysaccharide-iron complex (LPPC) was prepared under the alkaline condition by adding a ferric chloride solution to the low molecular weight porphyran (LP) solution. Physicochemical properties and inhibition effect on iron deficiency anemia of this complex were studied. The content of iron(III) in the complex is 21.57% determined with iodometry. The results indicate that LPPC was product required. The complex can increase red blood cell count (RBC), hemoglobin (Hb), Serum iron (SI), spleen index, spleen mass and mass of mice with iron deficiency anemia (IDA). Although the structure and deeper mechanisms on hemolytic anemia of LPPC should be further studied, LPPC is hoped to be developed as a late-model iron supplement which has a synergism on anemia.

Isolation and antioxidant activities of polysaccharides extracted from the shoots of Phyllostachys edulis (Carr.).

Polysaccharides extracted from Phyllostachys edulis (Carr.) are a group of hetero polysaccharides, and their antioxidant activities were investigated employing various established in vitro systems. Available data obtained with in vitro models suggested that among the three samples, B1 (extraction with water) showed significant inhibitory effects on superoxide radical and hydroxyl radical; its reducing power was also the strongest among the three samples. These results clearly establish the possibility that polysaccharides extracted from P. edulis could be effectively employed as ingredient in health or functional food, to alleviate oxidative stress. However, comprehensive studies need to be conducted in experimental animal models.

Optimization of polysaccharides extraction from Clematis huchouensis Tamura and its antioxidant activity.

In this study, response surface methodology (RSM), based on Box-Behnken design, was employed to optimize the extraction conditions of polysaccharide from Clematis huchouensis Tamura (CP). And then the antioxidant activities of the samples were investigated including scavenging effects of superoxide and hydroxyl radicals and their reducing power. The results of chemical composition and FT-IR spectrum analysis showed the polysaccharide was acidic proteoglycan. And moreover, CP showed excellent antioxidant activity in these three assays. The purification and structure of CP need to be further studied.

O-acetylation of low-molecular-weight polysaccharide from Enteromorpha linza with antioxidant activity.

Polysaccharide extracted from green algae Enteromorpha linza (EP) is a sulfated polysaccharide, which possesses excellent antioxidant activities. In present study, the acetylated derivatives of low-molecular-weight polysaccharide (LEP) was prepared with the method of response surface quadratic model. And then the antioxidant activities of the derivatives were investigated including scavenging effects of superoxide and hydroxyl radicals. The results of chemical analysis and FT-IR spectrum showed the acetylation was successful. And in addition, certain derivative with different degree of substitution (DS) exhibited different antioxidant activity.