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勒让德多项式 1

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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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Evolution of humic substances in polymerization of polyphenol and amino acid based on non-destructive

Jianmei Zou, Jianzhi Huang, Huichun Zhang, Dongbei Yue

《环境科学与工程前沿（英文）》 2021年第15卷第1期 doi: 10.1007/s11783-020-1297-y

摘要： Abstract • Humification evolution was identified with non-destructive characterization method. • Humification process from precursors to fulvic and humic acid was confirmed. • MnO2 alone had limited oxidation ability to form HA. • MnO2 played a key role as a catalyst to transform FA to HA in the presence of O2. • MnO2 could affect the structure of the humification products. Abiotic humification is important in the formation and evolution of organic matter in soil and compost maturing processes. However, the roles of metal oxides in abiotic humification reactions under micro-aerobic remain ambiguous. The aim of this study was to use non-destructive measurement methods to investigate the role of MnO2 in the evolution of humic substances (HSs) during oxidative polymerization of polyphenol-amino acid. Our results suggested a synergistic effect between MnO2 and O2 in promoting the polymerization reaction and identified that MnO2 alone had a limited ability in accelerating the transformation of fulvic acid (FA) to humic acid (HA), whereas O2 was the key factor in the process. Two-dimensional correlation spectroscopy (2D-COS) showed that the evolution in the UV-vis spectra followed the order of 475–525 nm>300–400 nm>240–280 nm in the humification process, indicating the formation of simple organic matter followed by FA and then HA. 13C nuclear magnetic resonance (13C NMR) analysis revealed that the products under both air and N2 conditions in the presence of MnO2 had greater amounts of aromatic-C than in the absence of MnO2, demonstrating that MnO2 affected the structure of the humification products. The results of this study provided new insights into the theory of abiotic humification.

关键词： Two-dimensional correlation spectroscopy (2D-COS) Humic substances (HSs) Humification Manganese dioxide Polyphenol

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Optimization of the main liming process for inulin crude extract from Jerusalem artichoke tubers

Huandong LI, Hongji ZHU, Jianjun QIAO, Junhu DU, Hua ZHANG

《化学科学与工程前沿（英文）》 2012年第6卷第3期页码 348-355 doi: 10.1007/s11705-012-1295-0

摘要： A three-stage homogenate extraction was used as a new method for inulin extraction from Jerusalem artichoke tubers. Compared with the results from conventional hot water extraction, the three-stage homogenate extraction gave higher yields and caused less degradation of the inulin. The inulin crude extract was then clarified by a carbonate-precipitation method, during which three variables — the quicklime mass, the reaction temperature and the reaction time were optimized for the main liming process to give the best clarification effect. A Plackett-Burman design, the path of steepest ascent method, a Box-Behnken design and response surface methodology (RSM) were employed in the experimental design. The optimal conditions for the main liming process were determined to be 12.0 g/L, 71.4°C and 8 min. The confirmatory tests proved that the best clarification efficiency (92.74%) was achieved at these conditions and this was approximately equal to the value predicted by the model.

关键词： inulin homogenate extraction Jerusalem artichoke main liming process

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Neuroprotective effects of Ginkgo biloba extract and Ginkgolide B against oxygen–glucose deprivation/

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《医学前沿（英文）》 2018年第12卷第3期页码 307-318 doi: 10.1007/s11684-017-0547-2

摘要：

Acute ischemic stroke (AIS), as the third leading cause of death worldwide, is characterized by its high incidence, mortality rate, high incurred disability rate, and frequent reoccurrence. The neuroprotective effects of extract (GBE) against several cerebral diseases have been reported in previous studies, but the underlying mechanisms of action are still unclear. Using a novel rat cortical capillary endothelial cell-astrocyte-neuron network model, we investigated the neuroprotective effects of GBE and one of its important constituents, Ginkgolide B (GB), against oxygen–glucose deprivation/reoxygenation and glucose (OGD/R) injury. In this model, rat cortical capillary endothelial cells, astrocytes, and neurons were cocultured so that they could be synchronously observed in the same system. Pretreatment with GBE or GB increased the neuron cell viability, ameliorated cell injury, and inhibited the cell apoptotic rate through Bax and Bcl-2 expression regulation after OGD/R injury. Furthermore, GBE or GB pretreatment enhanced the transendothelial electrical resistance of capillary endothelial monolayers, reduced the endothelial permeability coefficients for sodium fluorescein (Na-F), and increased the expression levels of tight junction proteins, namely, ZO-1 and occludin, in endothelial cells. Results demonstrated the preventive effects of GBE on neuronal cell death and enhancement of the function of brain capillary endothelial monolayers after OGD/R injury ; thus, GBE could be used as an effective neuroprotective agent for AIS/reperfusion, with GB as one of its significant constituents.

关键词： acute ischemic stroke Ginkgo bilobaextract Ginkgolide B network model neuroprotection

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Effect of incorporating Elaeagnus angustifolia extract in PCL-PEG-PCL nanofibers for bone tissue engineering

Vahideh R. Hokmabad, Soodabeh Davaran, Marziyeh Aghazadeh, Effat Alizadeh, Roya Salehi, Ali Ramazani

《化学科学与工程前沿（英文）》 2019年第13卷第1期页码 108-119 doi: 10.1007/s11705-018-1742-7

摘要：

Plants have been used for medicinal purposes for thousands of years but they are still finding new uses in modern times. For example, Elaeagnus angustifolia (EA) is a medicinal herb with antinociceptive, anti-inflammatory, antibacterial and antioxidant properties and it is widely used in the treatment of rheumatoid arthritis and osteoarthritis. EA extract was loaded onto poly(ϵ-caprolactone)-poly(ethylene glycol)-poly(ϵ-caprolactone) (PCL-PEG-PCL/EA) nanofibers and their potential applications for bone tissue engineering were studied. The morphology and chemical properties of the fibers were evaluated using Fourier transform infrared spectroscopy, field emission scanning electron microscopy, contact angle measurements and mechanical tests. All the samples had bead-free morphologies with average diameters ranging from 100 to 200 nm. The response of human cells to the PCL-PEG-PCL/EA nanofibers was evaluated using human dental pulp stem cells (hDPSCs). The hDPSCs had better adhesion and proliferation capacity on the EA loaded nanofibers than on the pristine PCL-PEG-PCL nanofibers. An alizarin red S assay and the alkaline phosphatase activity confirmed that the nanofibrous scaffolds induced osteoblastic performance in the hDPSCs. The quantitative real time polymerase chain reaction results confirmed that the EA loaded nanofibrous scaffolds had significantly upregulated gene expression correlating to osteogenic differentiation. These results suggest that PCL-PEG-PCL/EA nanofibers might have potential applications for bone tissue engineering.

关键词： Elaeagnus angustifolia scaffold electrospinning human dental pulp stem cell tissue engineering

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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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Preliminary study on preparation of cell-free system for protein expression

CHEN Haiqin, XU Zhinan, WANG Cheng, CEN Peilin, LIAO Yuhua

《化学科学与工程前沿（英文）》 2008年第2卷第2期页码 224-229 doi: 10.1007/s11705-008-0029-9

摘要： In the new era of “Omics”, the traditional techniques of protein expression in vivo can not come up with the exponential increase of genetic information. The cell-free protein synthesis system provides a new strategy of protein expression with advantages of rapid, convenient and high-throughput expression. The preparation of cell extracts, the optimization of substrate concentrations and the energy regeneration system are the key factors for the successful construction of cell-free protein expression system. In this work, the cell extract was prepared from RNase I- defective strain A19. The cell growth phase, the pressure for cell disruption and the storage condition of cell extracts were optimized. Meanwhile, the optimal substrate concentrations and the energy regeneration system were selected. Under the optimized conditions, the green fluorescent protein (GFP) reporter gene was expressed in the cell-free system with high expression level (Ca. 154 ?g/mL) which was 29 times higher than the expression level before optimization.

关键词： cell-free regeneration extract information successful construction

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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

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Lignin-based polymer with high phenolic hydroxyl group content prepared by the alkyl chain bridging method and applied as a dopant of PEDOT

《化学科学与工程前沿（英文）》 2023年第17卷第8期页码 1075-1084 doi: 10.1007/s11705-022-2272-x

摘要： Inspired by the importance of the phenolic group to the electron transporting property of hole transport materials, phenolic hydroxyl groups were introduced in lignosulfonate (LS) via the alkyl chain bridging method to prepare phenolated-lignosulfonate (PLS). The results showed that the phenolic group was boosted from 0.81 mmol∙g^–1 of LS to 1.19 mmol∙g^–1 of PLS. The electrochemical property results showed two oxidation peaks in the cyclic voltammogram (CV) curve of PLS, and the oxidation potential of the PLS-modified electrode decreased by 0.5 eV compared with that of LS. This result indicates that PLS is more easily oxidized than LS. Based on the excellent electron transporting property of PLS, PLS was applied as a dopant in poly(3,4-ethylenedioxythiophene) (PEDOT, called PEDOT:PLSs). PLS showed excellent dispersion properties for PEDOT. Moreover, the transmittance measurement results showed that the transmittance of PEDOT:PLSs exceeded 85% in the range of 300–800 nm. The CV results showed that the energy levels of PEDOT:PLSs could be flexibly adjusted by PLS amounts. The results indicate that the phenolic hydroxyl group of lignin can be easily boosted by the alkyl chain bridging method, and phenolated lignin-based polymers may have promising potential as dopants of PEDOT to produce hole transporting materials for different organic photovoltaic devices.

关键词： lignosulfonate phenolic group PEDOT:PLS hole extract layer energy level

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Microcystin-LR biodegradation by

Chengbin XIAO, Hai YAN, Junfeng WANG, Wei WEI, Jun NING, Gang PAN

《环境科学与工程前沿（英文）》 2011年第5卷第4期页码 526-532 doi: 10.1007/s11783-010-0261-7

摘要： A promising bacterial strain for biodegrading microcystin-LR (MC-LR) as the sole carbon and nitrogen source was successfully isolated from Lake Dianchi, China. The strain was identified as sp. USTB-05, which was the first isolated MCs-biodegrading sp. in China. The average biodegradation rate of MC-LR by sp. USTB-05 was 28.8 mg·L per day, which was apparently higher than those of other bacteria reported so far. The optimal temperature and pH for both strain USTB-05 growth and MC-LR biodegradation were 30°C and 7.0, respectively. The release of MC-LR from the cyanobacterial cells collected from Lake Guishui and the biodegradation of MC-LR by both strain and cell-free extract (CE) were investigated. The results indicated that MC-LR with the initial concentration of 4.0 mg·L in water was biodegraded by sp. USTB-05 within 4 d, while MC-LR with the initial concentration of 28.8 mg·L could be completely removed in 3 h by CE of sp. USTB-05 containing 350 mg·L protein. During enzymatic biodegradation of MC-LR, two intermediate metabolites and a dead-end product were observed on an HPLC chromatogram. Moreover, the similar scanning profiles of MC-LR and its metabolic products indicate that the Adda side-chain of MC-LR was kept intact in all products.

关键词： microcystin-LR(MC-LR) biodegradation Sphingopyxis sp USTB-05 cell-free extract

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反应堆含氚重水提氚关键技术研究进展

孙颖,王和义,桑革,罗阳明,曹伟,刘云怒,熊义富

《中国工程科学》 2007年第9卷第5期页码 1-6

摘要：

基于建立的年处理10t重水的组合电解催化交换唱色谱分离（CECE-GC）实验系统，就含氘轻水提氘演示实验及利用含氚轻水进行含氚重水提氚模拟运行做了介绍。结果表明，240h含氚轻水的连续运行，CECE系统整体浓缩倍数约为4，电解池氕、氚分离因子约为10；8 m³/d色谱分离系统运行23h，可将10.5m³料气的90％中的氘贫化1000倍；氚储存系统运转正常。CECE-GC实验系统的建立，为重水提氚技术的进一步工程化提供了研究平台。

关键词：重水提氚 CECE-GC 演示实验

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高阶高斯积分节点的高精度数值计算

张庆礼,王晓梅,殷绍唐,江海河

《中国工程科学》 2008年第10卷第2期页码 35-40

摘要：

在工程数值计算、X射线衍射线形分析、光谱学等领域常使用高斯数值积分，高斯积分的节点及权重因子是数值积分的必须数据。研究了高次勒让德、拉盖尔和厄米多项式的零点，即高斯-勒让德、高斯-拉盖尔、高斯-厄米积分的节点的计算方法，给出了一种有效的高精度数值算法——搜索迭代方法（scan-iteration method，SIM）。根据勒让德、拉盖尔、厄米多项式的特点，对拉盖尔多项式、厄米多项式的定义稍做变化后，获得了计算多项式值的稳定递推关系。求它们的根时，先在一定范围内以一定的步长搜索根所在的

关键词：高斯积分勒让德多项式拉盖尔多项式厄米多项式求根