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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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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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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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埋地热含蜡原油管道的非稳态传热问题

崔秀国,张劲军

《中国工程科学》 2003年 第5卷 第7期   页码 77-83

摘要：

我国生产的原油大多为含蜡原油，加热输送是含蜡原油的主要输送方式。埋地热含蜡原油管道的运行中涉及若干复杂的非稳态传热问题。从管内原油传热（内部传热）和管道与外部环境的传热（外部传热）两方面，分析和总结了含蜡原油管道非稳态传热问题的研究现状，介绍了管道在土壤中传热的影响因素，比较了其各种解析和数值解法，阐述了管道停输状态下管内含蜡原油相变传热的规律及研究方法，讨论了非稳定流动状态下管内油流的水力—热力耦合问题及求解方法，指出了埋地热含蜡原油管道的非稳态传热方面需进一步研究的问题。

关键词： 石蜡基原油     管道输送     非稳态传热    

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Exergy analysis of multi-stage crude distillation units

Xingang LI, Canwei LIN, Lei WANG, Hong LI

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 437-446 doi: 10.1007/s11705-013-1349-y

摘要： This paper aims to investigate the multi-stage effect on crude distillation units (CDUs) in thermodynamics. In this regard, we proposed three-, four-, five-, and six-stage CDU processes with all variables constrained to be almost the same except for the number of stages. We also analyzed the energy and exergy to assess the energy consumed by each process. Because additional distillation units would share the processing load and thus prevent products with low boiling points from overheating, the heat demand of the CDUs decreases with increasing stages and thus reduces the heat supply. Exergy loss is considered as a key parameter to assess these processes. When the exergy losses in heat exchangers are disregarded, the three- and four-stage CDUs have lower exergy losses than the five- and six-stage CDUs. When the overall exergy losses are considered, the optimum number of stages of CDUs depends on the exergy efficiency of heat integration.

关键词： exergy     exergy loss     crude oil distillation     multi-stage     energy saving    

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Impact of crude distillation unit model accuracy on refinery production planning

Gang FU, Pedro A. Castillo CASTILLO, Vladimir MAHALEC

《工程管理前沿（英文）》 2018年 第5卷 第2期   页码 195-201 doi: 10.15302/J-FEM-2017052

摘要： In this work, we examine the impact of crude distillation unit (CDU) model errors on the results of refinery-wide optimization for production planning or feedstock selection. We compare the swing cut+ bias CDU model with a recently developed hybrid CDU model (Fu et al., 2016). The hybrid CDU model computes material and energy balances, as well as product true boiling point (TBP) curves and bulk properties (e.g., sulfur % and cetane index, and other properties). Product TBP curves are predicted with an average error of 0.5% against rigorous simulation curves. Case studies of optimal operation computed using a planning model that is based on the swing cut+ bias CDU model and using a planning model that incorporates the hybrid CDU model are presented. Our results show that significant economic benefits can be obtained using accurate CDU models in refinery production planning.

关键词： impact of model accuracy on production planning     swing cut+ bias CDU model     hybrid CDU model     refinery feedstock selection optimization     optimization of refinery operation    

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易凝高粘原油管输技术及其发展

张劲军

《中国工程科学》 2002年 第4卷 第6期   页码 71-76

摘要：

我国所产原油80%以上为凝点较高的含蜡原油和粘稠的重质原油，其节能、安全输送一直是我国油气储运界面临的主要技术难题。简要介绍了这两类原油的流动特性及机理，概括了原油降凝减阻输送技术研究和应用的现状，分析了其发展趋势，提出了进一步研究需重点解决的问题。预计化学降凝剂改性仍将是含蜡原油节能安全输送技术的发展方向，目前需重点攻克大庆原油改性的难关；稠油乳化降粘减阻技术将得到更多的应用，在我国目前应重点针对海上油田的油水混输管道开展研究。现有技术的提升、新技术的涌现，有赖于基础研究的突破、技术路线的大胆创新和相关。

关键词： 管道输送     石蜡基原油     重质原油     降凝     减阻     化学添加剂    

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Microbial community and functional genes in the rhizosphere of alfalfa in crude oil-contaminated soil

Yi ZHONG, Jian WANG, Yizhi SONG, Yuting LIANG, Guanghe LI

《环境科学与工程前沿（英文）》 2012年 第6卷 第6期   页码 797-805 doi: 10.1007/s11783-012-0405-z

摘要： A rhizobox system constructed with crude oil-contaminated soil was vegetated with alfalfa ( L.) to evaluate the rhizosphere effects on the soil microbial population and functional structure, and to explore the potential mechanisms by which plants enhance the removal of crude oil in soil. During the 80-day experiment, 31.6% of oil was removed from the adjacent rhizosphere (AR); this value was 27% and 53% higher than the percentage of oil removed from the far rhizosphere (FR) and from the non-rhizosphere (NR), respectively. The populations of heterotrophic bacteria and hydrocarbon-degrading bacteria were higher in the AR and FR than in the NR. However, the removal rate of crude oil was positively correlated with the proportion of hydrocarbon-degrading bacteria in the rhizosphere. In total, 796, 731, and 379 functional genes were detected by microarray in the AR, FR, and NR, respectively. Higher proportions of functional genes related to carbon degradation and organic remediation, were found in rhizosphere soil compared with NR soil, suggesting that the rhizosphere selectively increased the abundance of these specific functional genes. The increase in water-holding capacity and decrease in pH as well as salinity of the soil all followed the order of AR>FR>NR. Canonical component analysis showed that salinity was the most important environmental factor influencing the microbial functional structure in the rhizosphere and that salinity was negatively correlated with the abundance of carbon and organic degradation genes.

关键词： crude oil-contaminated soil     phytoremediation     rhizosphere effects     rhizobox     functional genes    

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Analyzing the energy intensity and greenhouse gas emission of Canadian oil sands crude upgrading through

Anton ALVAREZ-MAJMUTOV,Jinwen CHEN

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 212-218 doi: 10.1007/s11705-014-1424-z

摘要： This paper presents an evaluation of the energy intensity and related greenhouse gas/CO emissions of integrated oil sands crude upgrading processes. Two major oil sands crude upgrading schemes currently used in Canadian oil sands operations were investigated: coking-based and hydroconversion-based. The analysis, which was based on a robust process model of the entire process, was constructed in Aspen HYSYS and calibrated with representative data. Simulations were conducted for the two upgrading schemes in order to generate a detailed inventory of the required energy and utility inputs: process fuel, steam, hydrogen and power. It was concluded that while hydroconversion-based scheme yields considerably higher amount of synthetic crude oil (SCO) than the coker-based scheme (94 wt-% vs. 76 wt-%), it consumes more energy and is therefore more CO -intensive (413.2 kg CO /m vs. 216.4 kg CO /m ). This substantial difference results from the large amount of hydrogen consumed in the ebullated-bed hydroconverter in the hydroconversion-based scheme, as hydrogen production through conventional methane steam reforming is highly energy-intensive and therefore the major source of CO emission. Further simulations indicated that optimization of hydroconverter operating variables had only a minor effect on the overall CO emission due to the complex trade-off effect between energy inputs.

关键词： Oil sands crude upgrading     hydroconversion     process modeling     greenhouse gas emissions    

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Impacts of different diameter combinations on the temperature of a crude oil pipeline when colocating

Bo YU, Yue SHI, Xin LIU, Jinjun ZHANG, Jinjia WEI,

《能源前沿（英文）》 2010年 第4卷 第2期   页码 192-197 doi: 10.1007/s11708-009-0074-1

摘要： In order to show the effects of different diameter combinations on crude oil temperature when a crude oil pipeline and a products pipeline are laid in one trench, four typical diameter combinations are selected to conduct numerical simulation. After a series of calculations, the minimum mean temperature difference and the maximum temperature difference of the crude oil along the pipelines are obtained. In real pipeline constructions, the effects of other diameter combinations on crude oil temperature can be predicted by the method of linear interpolation to calculate results of the four diameter combinations obtained in this study.

关键词： technology of laying two pipelines in one trench     diameter combinations     crude oil temperature     pipeline interval    

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Separation of epigallocatechin-3-gallate from crude tea polyphenols by using Cellulose diacetate graft

Hong ZHU, Peiyong QIN

《化学科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 330-338 doi: 10.1007/s11705-010-1104-6

摘要： This study demonstrates a new Cellulose diacetate graft -cyclodextrin (CDA- -CD) copolymer asymmetric membrane prepared by a phase inversion technique for the separation of (-)-epigallocatechin-3-gallate (EGCG) from other polyphenols in crude tea. The graft copolymer, CDA- -CD, was synthesized by prepolymerization of cellulose diacetate (CDA) and 1,6-hexamethylene-diisocyanate (HDI), which was then grafted with -cyclodextrin ( -CD). Surface and cross-section morphologies of the CDA- -CD membranes were analyzed by using scanning electron microscopy (SEM). Fourier transform infrared spectroscopy (FT-IR) indicated that the -CD was grafted onto the CDA by chemical bonding. The influences of the HDI/CDA mass ratio and the catalyst mass fraction on the -CD graft yield were investigated. The optimum conditions of a HDI/CDA mass ratio of 0.35 g·g and a catalyst mass fraction of 0.18 wt-% produced a -CD graft yield of 26.51 wt-%. The effects of the -CD graft yield and the concentration of the polymer cast solution on the separation of EGCG were also investigated. Under optimum conditions of a -CD graft yield of 24.21 wt-% and a polymer concentration of 13 wt-%, the purity of EGCG increased from 26.51 to 86.91 wt-%.

关键词： (-)-epigallocatechin-3-gallate (EGCG)     tea polyphenols     CDA-β-CD    

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

null

《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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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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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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标题 作者 时间 类型 操作

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

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

期刊论文

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

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

期刊论文

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

Jianmei Zou, Jianzhi Huang, Huichun Zhang, Dongbei Yue

期刊论文

埋地热含蜡原油管道的非稳态传热问题

崔秀国,张劲军

期刊论文

Exergy analysis of multi-stage crude distillation units

Xingang LI, Canwei LIN, Lei WANG, Hong LI

期刊论文

Impact of crude distillation unit model accuracy on refinery production planning

Gang FU, Pedro A. Castillo CASTILLO, Vladimir MAHALEC

期刊论文

易凝高粘原油管输技术及其发展

张劲军

期刊论文

Microbial community and functional genes in the rhizosphere of alfalfa in crude oil-contaminated soil

Yi ZHONG, Jian WANG, Yizhi SONG, Yuting LIANG, Guanghe LI

期刊论文

Analyzing the energy intensity and greenhouse gas emission of Canadian oil sands crude upgrading through

Anton ALVAREZ-MAJMUTOV,Jinwen CHEN

期刊论文

Impacts of different diameter combinations on the temperature of a crude oil pipeline when colocating

Bo YU, Yue SHI, Xin LIU, Jinjun ZHANG, Jinjia WEI,

期刊论文

Separation of epigallocatechin-3-gallate from crude tea polyphenols by using Cellulose diacetate graft

Hong ZHU, Peiyong QIN

期刊论文

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

null

期刊论文

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

期刊论文

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

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

期刊论文

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

期刊论文