Structure elucidation and antioxidant effect of a polysaccharide from Lactarius camphoratum (Bull.) Fr

Evaluation of the "Relative Ordered Structure of Hericium erinaceus Polysaccharide" from Different Origins: Based on Similarity and Dissimilarity

Polysaccharides are organic compounds widely distributed in nature, but structural order and disorder remain a formidable problem. In this study, based on the theoretical framework of the "relative ordered structure of polysaccharide" proposed in our previous work, the structural order of Hericium erinaceus polysaccharides from different regions was evaluated by FT-IR, methylation analysis, and 1H NMR spectroscopy combined with chemometric methods. The results of principal component analysis and heatmap cluster analysis revealed that 18-subfractions exhibit four different structural types with representative glycoside linkage types: fucogalactoglucan, glucofucogalactan, fucoglucan, and glucan. The main chain of heteroglucans often consists of β-(1 → 6)-Glcp, β-(1 → 4)-Glcp, and β-(1 → 3)-Glcp residues, which are predominantly substituted at the O-3 and O-6 positions. The main chain structure of heterogalactans is α-(1 → 6)-Galp residues, which may be replaced by Fucp and Galp residues at O-2. Overall, our findings demonstrate the validity of the "relative ordered structure of polysaccharide" in Hericium erectus polysaccharides and simplify the complexity of polysaccharide structures.

Synergistic Hypoglycemic Effects of Pumpkin Polysaccharides and Puerarin on Type II Diabetes Mellitus Mice

To investigate the hypoglycemic effect and potential mechanism of pumpkin polysaccharides and puerarin on type II diabetes mellitus (T2DM) mice, mice were fed a high-fat diet and injected intraperitoneally with streptozotacin to induce T2DM. After eight weeks of drug administration, blood samples were withdrawn from tail veins of mice that had been fasted overnight. The results showed that both pumpkin polysaccharides and puerarin, as well as a pumpkin polysaccharides and puerarin combination, could ameliorate T2DM. The pumpkin polysaccharides and puerarin combination had a synergetic hypoglycemic effect on T2DM mice that was greater than the pumpkin polysaccharides' or the puerarin's hypoglycemic effect. Both the pumpkin polysaccharides and the puerarin were found to ameliorate the blood glucose tolerance and insulin resistance of T2DM mice. They showed lipid-lowering activity by reducing the total cholesterol, triglycerides, and low-density lipoprotein levels, and improving the high-density lipoprotein level. They had beneficial effects on the oxidative stress by decreasing the reactive oxygen species and malondialdehyde levels, and increasing the glutathione level and the superoxide dismutase activity. Furthermore, the nuclear factor E2 related factor 2 (Nrf2), heme oxygenase-1, and phosphoinositide-3-kinase (PI3K) levels were upregulated, and the Nrf2 and PI3K signalling pathways might be involved in the hypoglycemic mechanism. The combined administration of pumpkin polysaccharides and puerarin could synergistically ameliorate T2DM.

Structural characterization, immune regulation and antioxidant activity of a new heteropolysaccharide from Cantharellus cibarius Fr

A new heteropolysaccharide was extracted and purified from the fruiting bodies of Cantharellus cibarius Fr. The Cantharellus cibarius Fr. polysaccharide (CC-1) had a molecular weight of 61,056 kDa and was mainly formed of the glucose and xylose at ratio of 5:1. Structure identification of CC-1 was analysed by a combined application of total hydrolysis, high performance liquid chromatography (HPLC), methylation analysis, gas chromatography-mass spectrometry (GC-MS), infrared (IR) spectra and nuclear magnetic resonance (NMR) spectroscopy. The experimental results showed that CC-1 had a backbone of 1,4-linked-β-D-glucose which branched at O-6 and the branches were mainly composed of 6→1)-α-D-xylopyranose residue. CC-1 exhibited significant in vitro antioxidant effect and proliferation effect of immune cells. The activity study showed CC-1 has ability to clear the ABTS⁺ free radical and DPPH⁻ free radical in a certain range of concentration. The proliferation activity of the immune cells showed that the proliferation effect on B cells was very significant (P<0.001) in the concentration of 0.625–80 mg/ml; and the effect of T cell proliferation was also very significant (P<0.001) in the concentration of 5–20 mg/ml. The result of this study introduced Cantharellus cibarius Fr. as a possible valuable source in exhibiting unique immunoregulatory and antioxidant properties.

Structure and antioxidant activity of a novel polysaccharide derived from Amanita caesarea

A heteropolysaccharide was isolated from the fruiting bodies of Amanita caesarea using a diethylaminoethyl-cellulose column, Sephacryl S‑300 gel column and Sephadex G‑200 column. The Amanita caesarea polysaccharide was predominantly composed of α-D-glucose and α-D-lyxose at a ratio of 2:1, and it had a molecular weight of 19,329 Da. The structural features of the Amanita caesarea polysaccharide were investigated by a combination of total hydrolysis, methylation analysis, gas chromatography-mass spectrometry, and infrared spectra and nuclear magnetic resonance spectroscopy. The results showed that Amanita caesarea polysaccharide (termed AC‑1) had a backbone of 1,4‑linked α‑D‑glucose and 1,3,6‑linked α‑D‑glucose, with branches of one 1‑linked α‑D‑lyxose residue. The antioxidant activity of AC‑1 was evaluated by two biochemical methods, 2,2-azino-bis diammonium (ABTS+) radical scavenging activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH-) radical scavenging activity. The uncontrolled production of free radicals is involved in various diseases, including cancer, atherosclerosis and degenerative aging processes. The results indicated that the Amanita caesarea polysaccharide exhibits strong antioxidant activity, thus, it may be a useful natural product antioxidant.

Structure elucidation, anticancer and antioxidant activities of a novel polysaccharide from Gomphus clavatus Gray

A novel heteropolysaccharide from the fruiting bodies of Gomphus clavatus Gray was isolated through Sephadex G-200 and DEAE-cellulose columns. The Gomphus clavatus Gray polysaccharide (GCG-1) was mainly composed of β-D-glucosepyranose (β-D-Glu) and α-D-galactopyranose (α-D-Gal) in a ratio of 3:2 and had a molecular weight of ~50,000 Da. The structure of GCG-1 was investigated by a combination of total hydrolysis, gas chromatography-mass spectrometry, methylation analysis, nuclear magnetic resonance spectroscopy and infrared spectra. The results indicated that GCG-1 had a backbone of (1 → 4)-β-D-glucosepyranose residues with branches at O-6 and the branches consisted of two with (1 → 3)-α-D-galactopyranose residue. Antioxidation test in vitro showed that it possessed strong free radical scavenging activity, which may be comparable to vitamin C and butylated hydroxytoluene. GCG-1 also induced the apoptosis of HepG-2 cells and affected the mRNA expression of various housekeeping genes in the HepG-2 cells. The results indicated that Gomphus clavatus Gray may be an ideal sources for antioxidant and anticancer agents.