Isolation, characterization and bioactivities of a new polysaccharide from Annona squamosa and its sulfated derivative

Sulfated polysaccharides from Rhodiola sachalinensis reduce d-gal-induced oxidative stress in NIH 3T3 cells

In this study, three sulfated polysaccharides (S-RSP_1-2, S-RSP_1-4 and S-RSP_1-8) from Rhodiola sachalinensis were produced by chlorosulfonic acid-pyridine method. d-gal was used to develop an oxidative stress model in the mouse embryonic fibroblast cell line NIH 3T3. Effects of the three sulfated polysaccharides on d-gal-induced oxidative stress were investigated. The results showed that S-RSP_1-4 improved the viability of the d-gal-induced oxidative stress in NIH 3T3 cells. The sulfated polysaccharides were found to have a better protective effect against d-gal-induced oxidative stress as compared to the native polysaccharide. Scanning electronmicroscopy also showed a significant change in the surface morphology of sulfated polysaccharides. In addition, the sulfated polysaccharides had noticeable DPPH radical-scavenging activity. In summary, our results demonstrated that d-gal was able to induce oxidative stress in NIH 3T3 cells, and sulfated group might play an important role in resistance to d-gal-induced oxidative damage.

Characterization of a new heteropolysaccharide from green guava and its application as an α-glucosidase inhibitor for the treatment of type II diabetes

Psidium guajava fruit is a subtropical fruit, functional food and traditional medicine for the adjuvant treatment of diabetes mellitus in China. To investigate the active components responsible for its health benefits, a novel heteropolysaccharide GP70-3 was purified by water extraction, ethanol precipitation and column chromatography. Structural characterization of GP70-3 was elucidated for the first time by monosaccharide composition assay, Fourier transform-infrared spectroscopy (FT-IR), methylation analysis, gas chromatography coupled with mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). The data revealed that GP70-3 contained a backbone of 1→3,6)-linked β-d-Galp, 1→5)-linked α-l-Araf, 1→6)-linked β-d-Galp and 1→3)-linked β-d-Galp, branched with 1→2,3,5)-linked α-l-Araf, 1→3)-linked α-l-Araf, 1→3)-linked α-l-Rhap, 1→3)-linked β-d-GlcpA, 1→3)-linked β-d-GalpA and terminated with →1)-linked β-d-Galp. Advanced structure studies showed GP70-3 consisted of irregular flakes with rounded-spherical pores. Moreover, GP70-3 exhibited outstanding α-glucosidase inhibitory activity in vitro, with an IC50 value of 2.539 ± 0.144 μM, which was 1867 times higher than that of the positive control acarbose (IC50 value of 4.744 ± 0.026 mM). Therefore, consumption of guava polysaccharides may be beneficial as an α-glucosidase inhibitor for reducing the postprandial blood glucose level and treating type II diabetes.

Anti-inflammatory and hepatoprotective effects of exopolysaccharides isolated from Pleurotus geesteranus on alcohol-induced liver injury

The present work investigated the hepatoprotective role of exopolysaccharides (EPS) isolated from the mushroom Pleurotus geesteranus with respect to alcohol-induced liver injury in mice. Based on a physico-chemical analysis, the EPS produced by Pleurotus geesteranus was identified as a heteropolysaccharide with α-glycosidic bond. The results revealed that prophylactic application of the EPS reduces detrimental alcoholic effects on the liver. This observation was followed by decreased levels of total cholesterol, triglycerides, CYP2E1 and pro-inflammatory mediators (TNF-α, IL-6, IL-1β, COX-2, NO and iNOS) in the liver homogenates, suggesting that the EPS exhibits anti-inflammatory and hepatoprotective effects. Moreover, the increased activity of hepatic enzymes (superoxide dismutase, glutathione peroxidase and catalase) and reduced lipid peroxidation status indicated that the antioxidative effect of the EPS contributes to alleviation of liver injury. Therefore, this study reports that the EPS produced by Pleurotus geesteranus could be considered a potential natural drug or functional food supplement for the prevention of liver damage.

Structural characterization and immunomodulatory activity of a novel polysaccharide from Ficus carica

A novel polysaccharide (FCPW80-2) with a molecular weight of 1.21 × 10⁵ Da was first isolated from Ficus carica through hot water extraction and several chromatographic methods.

Anti-hyperlipidemic and antioxidant effects of alkali-extractable mycelia polysaccharides by Pleurotus eryngii var. tuolensis

In this study, we noted that the Al-MPS from Pleurotus eryngii var. tuolensis provoked pharmacological effects on blood lipid profiles and oxidative stress. Animal studies demonstrated that Al-MPS showed potential effects on relieving hyperlipidemia and preventing oxidative stress, reflecting by decreasing the levels of serum enzyme activities (ALP, ALT and AST), restoring the activities of antioxidant enzymes (SOD, GSH-Px, CAT and T-AOC), down-regulating the MDA and LPO contents, as well as remitting the hepatic and cardiac tissues injury, respectively. The serum levels of TC, TG, LDL-C, VLDL-C, and HDL-C on mice treated with Al-MPS (500mg/kg bw) reached 2.48±0.08, 1.24±0.03, 0.84±0.02, 0.34±0.02, and 1.80±0.03mmol/L, which were lower/higher against the hyperlipidemia mice. The results clearly indicated that the Al-MPS could be used as a beneficial health food and potentially natural candidate medicine in preventing the high-fat emulsion-induced hyperlipidemia.

Purification, characterization and bioactivities of polysaccharides from Pleurotus ferulae

Pleurotus ferulae polysaccharides promote the maturation of dendritic cells.