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Antioxidant and antitumor effects and immunomodulatory activities of crude and purified polyphenol extract

Xiaohong Kou,Lihua Han,Xingyuan Li,Zhaohui Xue,Fengjuan Zhou

《化学科学与工程前沿（英文）》 2016年第10卷第1期页码 108-119 doi: 10.1007/s11705-016-1553-7

摘要： The antioxidant and antitumor effects as well as the immunomodulatory activities of crude and purified polyphenol extract from blueberries were investigated. The antioxidant and antitumor effects of the polyphenol extract were measured both and , and their effect on the immune systems of CD-1 tumor-bearing mice were also analyzed. assays demonstrated that blueberry purified polyphenol extract (BBPP) exhibited higher antioxidant activities than blueberry crude polyphenol extract (BBCP), but the opposite effect was observed . Both the and antitumor activity and the immunity assay showed that BBCP not only inhibited tumor growth, but also significantly improved the immunity of the mice. According to physical and histological studies, the CD-1 tumor-bearing mice treated with the polyphenol extract, especially high doses of BBCP experienced a higher quality of life than the positive control group (treated with cyclophosphamide). These results indicate that BBCP has significant antioxidant and antitumor activities and that it can enhance the immunity of CD-1 tumor-bearing mice.

关键词： crude polyphenol extract purified polyphenol extract blueberry antioxidant antitumor immunity

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Purification and characterization of a novel carbonyl reductase with high stereo-selectivity

YANG Ming, XU Yan, MU Xiaoqing, XIAO Rong

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 404-410 doi: 10.1007/s11705-007-0074-9

摘要： A novel NADPH-dependent carbonyl reductase was separated from CCTCC 203011. The enzyme gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), which was purified through ammonium sulfate, Diethylamino Ethanol (DEAE) sepharose Fast flow (FF), phenyl-sepharose FF and blue sepharose FF chromato graphy from cell-free extract. The molecular mass of the enzyme was about 30 kDa. The optimum pH and temperature for reduction were 4.5°C and 35°C, respectively. The Cu had strong restrictive effect on enzyme activity. In addition, the carbonyl reductase was an enzyme with high substrate specificity and stereo-selectivity, and showed high asymmetric reduction activity towards -hydroxyacetophenone and ethyl 4-chloro acetoacetate. For the asymmetric reduction of ?-hydroxyacetophenone and ethyl 4-chloro acetoacetate, ()-1-phenyl-1,2-ethanediol and ()-ethyl 4-chloro-3-hydroxybutanoate were produced by the purified enzyme, with the 100% and 94.3% e.e. value, respectively. Therefore, the enzyme could be one of the effective biocatalysts for asymmetric synthesis of chiral alcohols. The amino acid sequences of one peptide from the purified enzyme were analyzed by LC-MASS-MASS, and the carbonyl reductase showed some identity to the hypothetical protein CaO19.10414 reported.

关键词： asymmetric synthesis sulfate-polyacrylamide purified electrophoresis temperature

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Bioenergy recovery from landfill gas: A case study in China

Wei WANG, Yuxiang LUO, Zhou DENG

《环境科学与工程前沿（英文）》 2009年第3卷第1期页码 20-31 doi: 10.1007/s11783-009-0012-9

摘要： Landfill gas (LFG) utilization which means a synergy between environmental protection and bioenergy recovery was investigated in this study. Pressure swing adsorption technology was used in LFG purification, and laboratory experiment, pilot-scale test, and on-site demonstration were carried out in Shenzhen, China. In the laboratory experiment, A-type carbon molecular sieve was selected as the adsorbent by comparison of several other adsorbents. The optimal adsorption pressure and adsorption time were 0.25 MPa and 2 min, respectively, under which the product generation rate was 4.5 m /h and the methane concentration was above 90%. The process and optimization of the pilot-scale test were also reported in the paper. The product gas was of high quality compared with the National Standard of Compressed Natural Gas as Vehicle Fuel (GB18047-2000), when the air concentration in feed gas was under 10.96%. The demonstration project was composed of a collection system, production system, and utilization system. The drive performance, environmental protection performance, and economic feasibility of the product gas – as alternative fuel in passenger car, truck, and bulldozer – were tested, showing the feasibility technology for LFG utilization.

关键词： landfill gas (LFG) compressed purified landfill gas (CPLG) pressure swing adsorption (PSA) alternative vehicle fuel demonstration project