Chenyu Wang's research while affiliated with Liaoning ShiHua University and other places

Two polysaccharide fractions, GSP I-a and GSP II-b, were isolated from Gentiana scabra Bunge roots. Both GSP I-a and GSP II-b comprised seven monosaccharides: fructose, mannose, rhamnose, galacturonic acid, glucose, galactose, and fucose. Ultraviolet and infrared analyses show that GSP I-a and GSP II-b are proteoglycans. In vitro evaluation of the antioxidant activity suggests that GSP I-a and GSP II-b scavenge 1,1-diphenyl-2-picrylhydrazyl radicals. However, the scavenging activity of the latter is stronger than that of the former. GSP I-a and GSP II-b have relatively low reducing powers and scavenging activities toward superoxide anions and hydroxyls. GSP I-a and GSP II-b significantly increase lymphocyte proliferation when lipopolysaccharide is used as a mitogen for lymphocytes, but only GSP I-a can significantly increase lymphocyte proliferation within the test-dosage range when concanavalin A is used as a mitogen.

In this study, response surface methodology was employed to optimize the extraction of polysaccharides from Phellinus nigricans mycelia. A central composite design was adopted to determine optimum parameters (extraction time, extraction temperature, extraction frequency, and ratio of water to raw material) that could yield a maximum polysaccharide. Results revealed the following optimum extraction conditions: extraction time, 2.8h; ratio of water to raw material, 28; extraction frequency, 5; and extraction temperature, 95°C. Under optimized conditions, the experimental yield of P. nigricans mycelia polysaccharides was 15.33±0.21%, which is consistent with the predicted yield. The antioxidant activity assay in vitro showed that the polysaccharides exhibited a high scavenging activity against superoxide anion, hydroxyl, and 1,1-diphenyl-2-picrylhydrazyl radicals. These polysaccharides also exhibited a strong reducing power. Thus, these polysaccharides can be used as natural antioxidants in functional foods or medicine.

Response surface methodology was used to optimize the extraction of crude polysaccharides from the fruiting bodies of Gomphidius rutilus. A central composite design was adopted to determine the combination of factors (extraction time, extraction temperature, extraction frequency, and ratio of water to raw material) that resulted in the maximum crude polysaccharide production. Results showed that the optimum extraction conditions were as follows: extraction temperature, 95°C; ratio of water to raw material, 16; extraction time, 2.5h; and extraction frequency, 4. Under these conditions, the experimental yield of crude polysaccharides was 8.02±0.15%, which well agreed with the predicted yield. Evaluation of the antioxidant activity in vitro suggested that the crude polysaccharides had high scavenging activity for superoxide anion, hydroxyl, and 1,1-diphenyl-2-picrylhydrazyl radicals. The crude polysaccharides also showed strong reducing power. Thus, they can be used as natural antioxidants in functional foods or medicine.

Two novel polysaccharide fractions, GRMP1 and GRMP2, were isolated from the mycelium of Gomphidius rutilus through submerged fermentation. GRMP1 and GRMP2 had similar average molecular weights (35 and 31kDa, respectively), and were composed of glucose and xylose at molar ratios of 0.46:1 and 0.63:1, respectively. In vitro antioxidant tests showed that GRMP1 and GRMP2 partly scavenged superoxide radical but almost had no scavenging effect on 1,1-diphenyl-2-picrylhydrazyl free radical. The effect of GRMP1 on hydroxyl radicals was stronger than that of GRMP2. Both GRMP1 and GRMP2 had relatively low reducing power and significant lymphocyte proliferation activity. In the presence of concanavalin A or lipopolysaccharide as mitogens for lymphocytes, the lymphocyte proliferation activity increased for GRMP1 but not for GRMP2 within the test dosage range.

Water-soluble polysaccharides were obtained from Gentiana scabra Bunge. Response surface methodology was used to optimize the extraction conditions, and a central composite design was adopted to determine the optimal processing parameters. The optimum extraction conditions are as follows: extraction temperature, 100 °C; ratio of water to raw material, 26.56; extraction time, 3 h; and extraction frequency, 2. Under these conditions, the experimental yield of polysaccharides was 13.0 ± 0.25%, which was consistent with the predicted yield. In vitro evaluation of the antioxidant activity suggests that the polysaccharides have high scavenging activity to 1,1-diphenyl-2-picrylhydrazyl radicals, relatively lower reducing power and scavenging activity to superoxide anions and hydroxyls. The polysaccharides also show high anti-tumor activity in vivo.