[Show abstract][Hide abstract] ABSTRACT: Polysaccharides extracted from ginger 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, G2 (extract with acid solution) showed significant inhibitory effects on superoxide radical, hydroxyl and DPPH radical; its reducing power and iron(II) chelation activity was also the strongest. These results clearly establish the possibility that polysaccharides extracted from ginger could be effectively employed as an ingredient in health or functional food, to alleviate oxidative stress. However, comprehensive studies need to be conducted in experimental animal models.Highlights► Polysaccharides extracted from ginger are a group of hetero polysaccharides. ► The antioxidant activities were investigated employing various established in vitro systems. ► G2 (extract with acid solution) showed significant antioxidant activities.
No preview · Article · Aug 2011 · Carbohydrate Polymers
[Show abstract][Hide abstract] ABSTRACT: Porphyran, the sulfated polysaccharide from red algae Porphyra haitanensis, possesses excellent bioactivities, especially the immune activity. In order to provide a water-soluble macromolecule prodrug of 5-FU showing slow release of 5-FU, reducing side-effect, we employed porphyran as a drug carrier, and carried out fixation of 5-FU to porphyran at 6-position through acetyl spacer group via ester bond. The chemical characteristic and release behavior of 5-FU from the conjugate obtained were studied in vitro at 37°C in three different medium. The results represented that the release mechanism of all the conjugates was a typical Fickian diffusion. However, further in vivo studies on animal models are necessary to establish the efficiency of the system.
No preview · Article · Feb 2010 · Carbohydrate Polymers
[Show abstract][Hide abstract] ABSTRACT: Porphyran extracted from red algae Porphyra haitanensis is a sulfated polysaccharide, which possesses excellent antioxidant activities. In this study, we prepared the acetylated, phosphorylated and benzoylated derivatives of porphyran. 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 analysis and FT-IR spectrum showed the modifications of porphyran were successful. And in addition, we found that certain derivative exhibited stronger antioxidant activity than raw material. And the mechanism of the structure–function relationship of these derivatives needs to be attended to.
No preview · Article · Oct 2009 · Carbohydrate Polymers
[Show abstract][Hide abstract] ABSTRACT: We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into
monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the monosaccharide derivatives,
obtained with 1-Phenyl-3-methyl-5-pyrazolone (PMP), were separated by reverse-phase HPLC using a gradient elution process,
and monitored by ultraviolet detection at 245 nm. In the concentration range of 0.1–2.0 mmol/L, the peak area of each monosaccharide
had a good linear relationship with its concentration (r
2>0.998). The average recoveries of mannose, rhamnose, glucuronic acid, glucose, galactose, xylose, and fucose were 86.2%,
95.1%, 62.5%, 102.0%, 94.8%, 66.6%, and 105.1%, respectively. This method was accurate and had good reproducibility and could
be used to determine the monosaccharide contents of fucoidans.
No preview · Article · Sep 2009 · Chinese Journal of Oceanology and Limnology
[Show abstract][Hide abstract] ABSTRACT: Three sulfated polysaccharide derivatives (phosphorylated and aminated fucoidan) were synthesized, and their potential antioxidant activities were investigated employing various established in vitro systems. Two methods were used in phosphorylation fucoidan: polyphosphoric acid and POCl(3) method. Aminated fucoidan was prepared using the epichlorohydrin and ammonia water. All fucoidan derivatives possessed considerable antioxidant activity, and exhibited stronger antioxidant ability than fucoidan in certain tests. The phosphorylated fucoidan showed stronger hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and reducing power. The mechanism on influence the antioxidant activity of samples of phosphate and amino group was indicated.
No preview · Article · Mar 2009 · International journal of biological macromolecules
[Show abstract][Hide abstract] ABSTRACT: Gelidium amansii agar was fractionated on DEAE-cellulose and four fractions were obtained sequentially. The yields of 1.0 mol/L NaCl fraction
and 2.5 mol/L NaCl fraction were 2.80% and 2.03%. They are highly sulfated agar, and named as agaropectin with sulfate content
being 22.8% and 32.5%, respectively. The anticoagulant experiment results show that agaropectin could effectively prolong
the coagulation time in a dose-dependent manner in vitro. Agaropection could be absorbed and effectively prolong the plasma coagulation time in vivo. After intragastric administration at the doses of 100, 200, and 400 mg/kg·d in rats for 15 days, TT (thrombin time), CT
(coagulation time), PT (prothrombin time), and APTT (activated partial thromboplastin time) could be effectively prolonged
and the plasma Fib level could be significantly lowered.
No preview · Article · Apr 2008 · Chinese Journal of Oceanology and Limnology