Search

Tricholoma lobayense is a nutritious mushroom with great health benefits. Three polysaccharides with purity higher than 99% were successfully extracted from Tricholoma lobayense . The molecular weights of TLH-1, TLH-2 and TLH-3 were determined to be 8.43 × 10 5 ，5.36 × 10 5 and 4.53 × 10 3 Da, respectively. The backbones of TLH-1 and TLH-2 were mainly composed of 1,4-linked α- d -glucopyranosyl. However, polysaccharide TLH-3 was found to be a highly branched glucogalactan, which is made up of 1,3-linked α- d -glucopyranosyl branched at C-6 and 1,3-linked β - d -galactopyranosyl. In vitro antioxidant activity assays revealed that TLH-3 exhibited highest antioxidant activities among the polysaccharides from Tricholoma lobayense , which were comparable to those of ascorbic acid. The results suggested that the outstanding antioxidant activities of TLH-3 might depend on its low molecular weight, high branch degree, versatile linkage types and complex conformation. These characteristics make TLH-3 an attractive natural antioxidant for food and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Abstract: Two sulfated polysaccharide fractions (S1 and S2) were successfully isolated from seaweed Undaia pinnitafida and the chemical characteristics were determined. Antioxidant activities of the polysaccharide fractions were evaluated by assays of various antioxidants in vitro systems, including superoxide anion, 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical-scavenging activity and metal chelating ability. The results showed that the two sulfated polysaccharides contained rhamnose as the major neutral sugar and present high sulfate content (33.99–34.29%). Antioxidant assays suggested that the two sulfated polysaccharide fractions (S1 and S2) possessed good antioxidant properties and had stronger antioxidant abilities than de-sulfated polysaccharides (DS-1 and DS-2). Available data obtained by in vitro models suggested that the correlation between the sulfate content and antioxidant activity was positive. [Copyright &y& Elsevier]

A facile and environmentally-friendly strategy for increasing antioxidant activity is a crucial issue for value-added lignin and lignin-carbohydrate complex (LCC) as alternative antioxidants. However, the antioxidant activities of lignin and LCC by the traditional solid-liquid extraction (SLE) methods were restricted by the relatively lower solubility induced from high molecular weight (Mw), and the less functional groups including, phenolic hydroxyl and carboxyl. To improve the antioxidantion of lignin and LCC, lithium chloride/dimethyl sulfoxide (LiCl/DMSO) solvent fractionation (LDSF) was conducted to increase the functional groups and reduce Mw, in which LiCl/DMSO acted triple roles as solvent, acid, and metal chloride catalyst for the depolymerization reaction synchronously. The β-O-4′ linkages were cleaved to release the phenolic hydroxyl, resulting in decreasing Mw; the hydroxyl of the side-chain of lignin was oxidized into carboxyl. Thus, the lignin (LD-RL) and LCC (LD-LCC) samples from LDSF had a higher syringyl (S)/guaiacyl (G) ratio, phenolic hydroxyl, and carboxyl contents, but less Mw than control groups from SLE. Consequently, they presented more excellent scavenging rates toward DPPH and ABTS radicals, up to 90%. This work provided panoramic perspectives and basics of the green and convenient approach to isolate and modify lignin and LCC for great antioxidantion with LDSF. • The lignin and LCC with high yield and antioxidantion were isolated from LDSF. • LiCl/DMSO acted triple roles as solvent, acid, and metal chloride catalyst. • Depolymerization induced by LiCl increased the functional groups and reduced Mw. • The higher S/G ratio, phenolic OH and COOH contents improved the antioxidantoin. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the structural features, in vitro and in vivo antioxidant activities of a heteropolysaccharide from the fruiting bodies of Morchella esculenta (FMP-1). FMP-1 had an average molecular weight of 4.7 × 10 3  Da and consisted of mannose, glucose and galactose. By methylation and NMR analysis, the backbone of FMP-1 was deduced to be made up of 1,4-linked Glc p and 1,6-linked Gal p . Hydroxyl, DPPH and superoxide radicals could be efficiently scavenged by FMP-1, with IC 50 values of 74.26, 119.32 and 161.49 μg/mL, respectively. Furthermore, FMP-1 could significantly protect zebrafish embryos against AAPH-induced oxidative damage. Decrease in malformations and mortalities was observed along with the reduction of ROS production, NO production and cell death. The protective effects were by decreasing MDA content and increasing SOD, CAT and GSH-Px levels. The current work provided a good suggestion of the potential utilization of FMP-1 as an attractive natural antioxidant. [ABSTRACT FROM AUTHOR]

Response surface method (RSM) was employed to optimize the extraction conditions of polysaccharides from Rhizoma Panacis Majoris (the rhizomes of Panax japonicus C. A. Mey. var. major (Burk.) C. Y. Wu et K. M. Feng) (RPMP), a well-known Chinese traditional medicine. In order to obtain the optimal processing parameters, a three-variable Box–Behnken designs (BBD) were applied for experimental designs. RSM analysis indicated the good correspondence between experimental and predicted values, the optimal conditions for the yield of polysaccharides were as follows: the ultrasound time is 31.15 min, extraction temperature is 92.50 °C, and the ratio of water to raw material is 40 mL/g. The maximum value (13.87 ± 0.16%) of the yield of polysaccharides was obtained under these optimal conditions. The molecular weight ( M W ) was determined to be 1.48 × 10 5 (± 0.39%) Da by HPSEC-MALLS-RID chromatography system. FT-IR spectra demonstrated obvious characteristic peaks of polysaccharides. The antioxidant activities of RPMP were investigated including scavenging activity of hydrogen radicals, ABTS radicals, and free radicals of superoxide anion in vitro , and the results exhibited that RPMP had a good potential for antioxidant. [ABSTRACT FROM AUTHOR]

Polysaccharides from edible fungi usually exhibit many bioactivities. Our previous studies found that polysaccharide TLH-3 extracted from Tricholoma lobayense possessed noticeable antioxidant activity. To further explore its biological activities, the antioxidant and anti-aging activities of TLH-3 were evaluated in vitro and in vivo . The results of antioxidant activity in vitro showed that TLH-3 could enhance the cell viability, reduce the production of reactive oxygen species (ROS) and inhibit oxidative damage induced by tert -butylhydroperoxide ( t -BHP) in human embryonic lung fibroblasts (HELF) cells. The anti-aging capability was measured in d -galactose ( d -gal)-induced aged mice model, and the experimental data showed that TLH-3 significantly inhibited the formation of malondialdehyde (MDA) and raised the activities of superoxide dismutase (SOD) and catalase (CAT) in mice liver and serum ( p < 0.05). This study suggested that TLH-3 possessed apparent antioxidant and anti-aging activities and could be exploited as a potent dietary supplement to attenuate aging and prevent age-related diseases in humans. [ABSTRACT FROM AUTHOR]

Our previous studies have revealed that the Tricholoma lobayense polysaccharide TLH-3, which has an IC50 value for scavenging superoxide radicals comparable to that of Vitamin C (VC), could be prepared by hot water extraction and column chromatography. However, this method is tedious and inefficient. In this study, high-pressure homogenization (HPH) was used to extract polysaccharides from T. lobayense Heim. The yield of 17.3% using HPH was higher than the 12.3% yielded by traditional extraction. Moreover, the operation combined quaternary ammonium salt precipitation with ultrafiltration (QASP-UF) to purify the crude polysaccharides successfully, which provided a higher TLH-3′ yield, a larger separation volume, and a shorter purification time than that of column chromatography. The whole process for TLH-3′ preparation presented here exhibited significant advantages of quicker processing, low consumption, high efficiency, and flexible compatibility with follow-up studies. Based on a characterization of molecular weight, Fourier Transform Infrared Spectroscopy (FT-IR) analysis, and monosaccharide composition analysis, it can be concluded that TLH-3 and TLH-3′ are the same polysaccharide. Antioxidant activity was tested to prove that the TLH-3′ prepared in this study could scavenge DPPH and superoxide radicals, with IC50 values of 111.7 μg/mL and 160.0 μg/mL, respectively. Its outstanding antioxidant ability was comparable to that of ascorbic acid. [ABSTRACT FROM AUTHOR]

Abstract: Sulfated polysaccharides (F1, F2) from seaweed Corallina officinalis were isolated through anion-exchange column chromatography. Their chemical characteristics were determined by GC, HPLC, FT-IR and UV spectra. F1 and F2 contained only two monosaccharides, namely galactose and xylose. The antioxidant activities of F1, F2 and the de-sulfated polysaccharides (DF-1, DF-2) in vitro were investigated, including hydroxyl radicals scavenging effect, superoxide radical scavenging capacity, DPPH radical activity and reducing power. As expected, antioxidant assay showed that the two sulfated polysaccharide fractions (F1, F2) possessed considerable antioxidant properties and had more excellent abilities than de-sulfated polysaccharides (DF-1, DF-2). [Copyright &y& Elsevier]