Structure elucidation and anti-tumor activities of water-soluble oligosaccharides from Lactarius deliciosus (L. ex Fr.) Gray

Structural characterization and protective effect on PC12 cells against H2O2-induced oxidative damage of a polysaccharide extracted from mycelia of Lactarius deliciosus Gray

The crude polysaccharide LDP was extracted from mycelia of Lactarius deliciosus Gray and then purified by DEAE-52 cellulose and Sephadex G-200 to obtain a novel polysaccharide named LDP-CP. LDP-CP was mainly composed of mannose, glucose and galactose with an average molecular weight of 2.33 × 10³ kDa. The structure of LDP-CP was determined by FT-IR, methylation and NMR analysis, and the results showed that the sugar linkage units of LDP-CP were composed of (1 → 3)-linked β-D-Manp, (1 → 2,4)-linked α-D-Manp, (1→)-linked α-D-Manp, (1 → 4)-linked β-D-Glcp, (1 → 2)-linked β-D-Manp, (1 → 4,6)-linked α-D-Manp, (1 → 4)-linked α-D-Galp, (1 → 2,3)-linked α-D-Glcp and (1→)-linked α-D-Glcf. The protective effects of LDP and LDP-CP on PC12 cells against H₂O₂-induced oxidative injury were exhibited by enhancing cell viability and morphological protection. The improvement to the level of LDH, SOD and GSH further indicated that LDP and LDP-CP had ability to alleviate H₂O₂-induced oxidative damage on PC12 cells. The polysaccharides in Lactarius deliciosus Gray mycelia exhibited the great advantages in the management of oxidative toxicity, which indicated that the polysaccharides can be further developed in application of natural functional food source.

Ultrasonic extraction, structural characterization, and antioxidant activity of oligosaccharides from red yeast rice

Red yeast rice is consumed as a medicinal food to lower blood lipids. Besides, it is used to color food, make wine, etc. In this study, water-soluble oligosaccharides in red yeast rice were extracted by ultrasonic-assisted extraction method. The parameters to extract oligosaccharides from red yeast rice were optimized by the Box-Behnken design under the following optimal extraction conditions: extraction temperature, 60°C; extraction time, 97 min; and liquid/material ratio, 25 ml/g. The structure and the antioxidant activity of the new oligosaccharide were preliminarily investigated. Total carbohydrates extracted from red yeast rice with 80% ethanol-water solution (v/v) were first removed from pigments using D101 macroporous adsorption resin. The total sugar contents were then purified by DE52 resins and Sephadex G-25 resins to obtain red yeast rice oligosaccharides, coded as RYRO1. Structural characterization experiments indicated that RYRO1 is an oligosaccharide with a weight average molecular weight of 874 Da and a theoretical degree of polymerization of 4.86. RYRO1 is composed of mannose, glucosamine, glucose, and galactose with a molar ratio of 0.248:0.019:1:0.026. The ABTS, DPPH, and hydroxyl free radical scavenging assays showed antioxidant nature of RYRO1.

Mushrooms as potential therapeutic agents in the treatment of cancer: Evaluation of anti-glioma effects of Coprinus comatus, Cantharellus cibarius, Lycoperdon perlatum and Lactarius deliciosus extracts

Cancer incidence rates are on the increase worldwide. The most common brain cancer in adults is glioblastoma. Currently available treatment modalities are limited and natural products such as mushrooms could enhance them. Apart from nutritional value, mushrooms are an excellent source of bioactive compounds and therefore could be used to treat various disorders. The aim of the study was to assess the anti-glioma potential of selected mushrooms on U87MG, LN-18 glioblastoma and SVGp12 normal human astroglial cell lines. The materials were Cantharellus cibarius, Coprinus comatus, Lycoperdon perlatum and Lactarius delicious. Aqueous, 70 % ethanol or 95 % ethanol extracts from mushrooms were used for analysis including assessment of antioxidant activity by DPPH assay, cell viability by MTT assay, DNA biosynthesis by thymidine incorporation assay, activity of metalloproteinase by gelatin zymography and cell cycle assay by flow cytometry. Mushroom extracts influenced the viability and DNA biosynthesis of cancer cells. Activity of ethanol mushroom extracts was stronger than that of aqueous extracts. Anti-glioma mechanism consisted in inhibition of cancer cell proliferation and induction of apoptosis associated with arrest of cells in subG1 or G2/M phase of cell cycle, and inhibition of metalloproteinases activity. Among investigated mushrooms, L. deliciosus and C. comatus showed the greatest anti-glioma potential.

Structural characterization and immune regulation of a novel polysaccharide from Maerkang Lactarius deliciosus Gray

The present study investigated the structural characterization and immune regulation of a novel polysaccharide from Maerkang Lactarius deliciosus Gray. Chemical methods, high performance gel permeation chromatography, fourier transform infrared spectroscopy, nuclear magnetic resonance spectrum and gas chromatography‑mass spectrometry were used to characterize the polysaccharide structure. The immunomodulatory abilities of the Maerkang L. deliciosus Gray polysaccharide (LDG‑M) were also investigated. LDG‑M was primarily composed of β‑D‑glucose and α‑D‑lyxose with the ratio of 2:1. The possible structure of LDG‑M had a backbone of 1,6‑linked‑β‑D‑glucose and 1,4,6‑linked‑β‑D‑glucose, with branches primarily composed of one (1→4)‑linked‑α‑D‑lyxose residue. The immunoregulatory activity results demonstrated that LDG‑M promoted the proliferation and phagocytosis of macrophages, and induced cytokine release. LDG‑M also promoted the proliferation of B cells by affecting the G0/G1, S and G2/M phases. The present study introduced LDG‑M as a valuable source with unique immunoregulatory properties.

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.