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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]

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]

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]