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Production of rhamnolipids-producing enzymes of

Kata Kiss,Wei Ting Ng,Qingxin Li

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 133-138 doi: 10.1007/s11705-017-1637-z

摘要： Rhamnolipids are a class of biosurfactants that have a great potential to be used in industries. Five proteins/enzymes, namely RhlA, RhlB, RhlC, RhlG and RhlI, are critical for the production of rhamnolipids in . Four of the 5 proteins except RhlC were successfully over-expressed in and three of them (RhlA, RhlB and RhlI) were purified and obtained in milligram quantities. The purified proteins were shown to be folded in solution. Homology models were built for RhlA, RhlB and RhlI. These results lay a basis for further structural and functional characterization of these proteins to favor the construction of super strains for rhamnolipids production.

关键词： rhamnolipids     Pseudomonas     RhlA     RhlB     RhlI     protein folding    

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Effect of a new antitranspirant on the physiology and water use efficiency of soybean under different irrigation rates in an arid region

Shasha JI, Ling TONG, Fusheng LI, Hongna LU, Sien LI, Taisheng DU, Youjie WU

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 155-164 doi: 10.15302/J-FASE-2017148

摘要： Antitranspirants are exogenous substances applied to leaves to reduce luxury transpiration by regulating stomatal conductance to increase water use efficiency (WUE). A cheap and environmentally-friendly antitranspirant, FZ, was newly developed, extracted mainly from . Its effects on soybean water use were investigated in a field experiment using the locally-used irrigation rate and a low irrigation rate (The lower and upper limit of irrigation is 40%–70% of field capacity). Foliar application of FZ and measurement of leaf physiological characteristics, final biomass, seed yield and water use efficiency were carried out during the pod bearing and pod filling stages of drip-irrigated soybean with film-mulching. Under the low irrigation rate, leaf stomatal conductance (g ) and transpiration rate (Tr) decreased significantly by 7 d after spraying, but photosynthesis (Pn) and instantaneous water use efficiency (WUE ) were not significantly affec ted. The stomatal frequency, stomatal aperture, g , Tr and Pn decreased by 1 d after spraying, without significantly increasing WUE . However, applying FZ during the pod bearing and pod filling stages did not significantly affect the final biomass, water consumption, seed yield and WUE of soybean. Under the locally-used irrigation rate, applying FZ increased the activities of superoxide dismutase and peroxidase in the leaves by 38% and 33%, respectively, but did not significantly affect g , Tr, Pn, stomatal aperture and stomatal frequency. Applying FZ three times during pod bearing and pod filling stages enhanced seed yield and WUE by 24% and 21%, respectively, but did not significantly affect the final biomass and water consumption. Therefore, seed yield and WUE of soybean were significantly increased by foliar application of FZ during the pod bearing and pod filling stages under the locally-used irrigation rate in arid region, but applying FZ did not have a positive effect on water use efficiency of soybean under a low irrigation rate.

关键词： antitranspirant     soybean     water deficit     leaf gas exchange     enzymes activities     water consumption     seed yield    

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Estrogenic activities of di-2-ethylhexyl phthalate

JIN Qiumei, LI Yan, SUN Zengrong

《医学前沿（英文）》 2008年 第2卷 第3期   页码 303-308 doi: 10.1007/s11684-008-0058-2

摘要： Phthalate esters are widespread in the environment. They have been described as being one of the most abundant man-made environmental contaminants that may be adverse to human health. Particularly, di-2-ethylhexyl phthalate (DEHP) has been shown to cause reproductive and developmental toxicity and is suspected to be an endocrine disruptor. The primary objective of this study is to determine the estrogenic activity of DEHP. Estrogenic activities of DEHP were studied by assays of human breast cancer MCF-7 cell proliferation. Estrogen-dependent MCF-7 cells were grown in RPMI1640 medium containing 10% fetal bovine serum. Five days before the addition of the test compounds, the cells were washed by phosphate balanced solution (PBS), and the medium was substituted with a phenol red-free RPMI1640 medium containing 5% dextral charcoal-stripped Fetal Bovine Serum (FBS). Fresh medium was added to the respective test compounds and the control cell received only the vehicle (ethanol). The proliferation of MCF-7 cell was analyzed by the MTT assay, growth curves, mitotic index and colony forming efficiency. Compared with the ethanol control cells, the proliferation of tested cells treated with DEHP, like estradiol, was significantly enhanced and the activity of the cell proliferation reached the maximum at 1 × 10 mol/L DEHP. The relative proliferative potency of DEHP was 0.000 001 with a relative proliferative effect of 97.32%. During the log phase, the mitotic index of the tested cells treated with DEHP and estradiol was significantly increased. The cell cloning efficiency was enhanced, which was treated by 10 mol/L DEHP only for 48 hours. The results show a time-dependent and dose-dependent model. Di-2-ethylhexyl phthalate enhanced the proliferation of human breast cancer MCF-7 cells and might demonstrate an estrogenic activity.
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Expression profiles of genes and enzymes related to ascorbic acid metabolism in fruits of

Yingying CHEN,Zhihui ZHAO,Jin ZHAO,Mengjun LIU

《农业科学与工程前沿（英文）》 2016年 第3卷 第2期   页码 131-136 doi: 10.15302/J-FASE-2016096

摘要： The fruit of Chinese jujube ( ) possesses extremely high concentrations of ascorbic acid (AsA). The accumulation of AsA, the expression patterns of the nine genes related to AsA metabolism as well as the activities of five enzymes involved in AsA synthesis, oxidation and recycling were investigated during fruit development in Mill. ‘Jinsixiaozao’. The results showed that the high level of AsA accumulation in jujube fruit is due to a contribution from both AsA biosynthesis and AsA recycling. It is suggested that L-galactono-1,4-lactone dehydrogenase, ascorbate peroxidase and monodehydro-ascorbate reductase are the crucial genes/enzymes of jujube AsA synthesis, oxidization and recycling, respectively. These results provide useful new insights into the regulatory mechanisms of AsA accumulation in Chinese jujube.

关键词： Chinese jujube     ascorbic acid     metabolism     gene     enzyme    

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Microbial biodegradation of plastics: Challenges, opportunities, and a critical perspective

《环境科学与工程前沿（英文）》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1596-6

摘要：

● Health hazards of plastic waste on environment are discussed.

关键词： Plastic-waste     Polymers     Health-hazards     Biodegradation     Microorganisms     Enzymes    

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Biodegradation and detoxification of the triphenylmethane dye coomassie brilliant blue by the extracellular enzymes

Jin Zhao, Qing-Xi Wu, Xiao-Du Cheng, Ting Su, Xiao-Hui Wang, Wen-Na Zhang, Yong-Ming Lu, Yan Chen

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 421-436 doi: 10.1007/s11705-020-1952-7

摘要： Fungi play an important role in dying wastewater treatment. In this work, the mycelia of exhibited an excellent capacity in decolorizing coomassie brilliant blue (CBB). The results demonstrated that the mycelia could treat CBB with high concentrations over a broad range of pH and temperature. The decolorization rate of 99.19% and the removal rate of 16.31 mg·L ·h were realized. The mycelia could be recycled from decolorizing process for 19 times, indicating a good re-usability. It verified that the lignin peroxidase (121.65 U·L ) and manganese peroxidase (36.77 U·L ) were involved in the degradation and decolorization process of CBB. Toxicity assessments indicated the seed germination rate was up to 82.22% while inhibition to decreased dramatically and no significant effect on growth was found. The removal of CBB was a synergistic process accomplished by adsorption and biodegradation. The mycelia could be used for eco-friendly CBB treatment.

关键词： fungus mycelia     biodegradation     extracellular enzymes     coomassie brilliant blue     Lactarius deliciosus    

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Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

《化学科学与工程前沿（英文）》 2022年 第16卷 第7期   页码 1090-1100 doi: 10.1007/s11705-021-2091-5

摘要： Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by 1H nuclear magnetic resonance (NMR), 13C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.

关键词： synthesis     pyrimidin-4-amine derivatives     1     2     4-oxadiazole     insecticidal activity     structure-activity relationship    

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我国航天的成就与发展

王礼恒

《中国工程科学》 2008年 第10卷 第12期   页码 10-12

摘要：

概述了国际航天发展的现状，对国际航天发展的新趋向“新世纪航天新计划”及其特点进行了概括，同时客观地总结了我国航天事业发展所取得的辉煌成就，在此基础上充分地展望了我国航天事业未来的发展愿景。

关键词： 中国航天     航天新计划     中国航天成就    

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A comparison of the biological activities of ethyl acetate fractions from the stems and leaves of

Zhaolei WANG, Kai JIANG, Qinchao DING, Shujun LIU, Xiaobing DOU, Bin DING

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 505-512 doi: 10.15302/J-FASE-2019271

摘要：

Pursh (PCP) is a popular traditional medicinal plant in China, widely used for the treatment of a variety of liver diseases. Although it has been long recognized that the main active elements of PCP are contained in ethyl acetate fraction (EAF), little is known so far in terms of the relative effectiveness of EAF derived from the stems versus leaves of this plant. In the current study, we prepared EAF by reflux extraction and sequential extraction from the stems (SEAF) and leaves (LEAF) of PCP and tested their hepatoprotective efficacies. The extract rates and flavonoid contents of LEAF were higher than those of SEAF. EAFs (>50 μg·mL ) prevented lipid accumulation in cells and protected against lipotoxicity injury when the concentration exceeded 25 μg·mL . More than 95% free radicals released by 2,2-diphenyl-1-picrylhydrazyl (DPPH) were eliminated by 25 μg·mL SEAF and 50 μg·mL LEAF, respectively. Further, EAFs (25 μg·mL ) also showed protective antioxidant effects, with the activity of LEAF being significantly higher than that of SEAF. EAFs (10 mg·mL ) also showed similar unspecific bacteriostatic activity. In comparison with SEAF, LEAF contained more flavonoids and had a higher anti-oxidation capability and for these reasons we suggest it should be better for clinical use.

关键词： antibacterial     anti-oxidation     lipid accumulation     lipotoxicity     Penthorum chinense Pursh    

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试论人类水事活动的新思维

李佩成

《中国工程科学》 2000年 第2卷 第2期   页码 5-9

摘要：

总结过去，展望未来，作者提出新世纪人类水事活动的新思维，并用大量事例和数据作了论证，认为在21世纪的水事活动中必须正确处理人类活动、水体动态、生态环境、经济发展与社会进步的关系，简称人-水-环-发-社关系；要特别把握人类水事活动和其它人类活动对水体动态的长期影响及其逆反作用；要把水库视为保护和恢复水源的决定性措施加以实现；正确处理耕地、绿地和水域的关系，保护并适当增大水体面积，保护沼泽，关心小河小水的命运；在未来水事活动中要从与天的抗争转变为适应与利用，充分运用各种信息技术建立“信息水利”，并通过对水文气象的把握，经营“应变农业”，从而在获得足够农产品的同时能在用水量最大的部门求得战略性的节水途径。

关键词： 水事活动     节水     水保护     新思维    

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中国航天的发展战略和重点领域

孙来燕

《中国工程科学》 2006年 第8卷 第10期   页码 6-12

摘要：

回顾了中国航天50年来取得的成就，总结了中国航天发展的经验及存在的差距；就国际航天的发展趋势，阐述了我国航天未来的发展战略及重点发展领域。

关键词： 中国航天     发展战略     重点领域    

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Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

《环境科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 218-223 doi: 10.1007/s11783-008-0037-5

摘要： To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated. Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase were determined by potassium permanganate titration, TTC (CHN·Cl) colorimetry, phenyl phosphate dinatrium colorimetry, and anthrone colorimetry, respectively. The result showed that soil pH, organic carbon (C), and total nitrogen (N) had great effects on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 0–20 cm thick soil. However, pH only had great effect on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 20–40 cm thick soil. Hydrogen peroxidase, dehydrogenase, and alkaline phosphatase were important biological indicators for the fertility of urban forest soil. Both in 0–20 cm and 20–40 cm soil, soil enzyme system (hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase) had a close relationship with a combination of physicochemical indicators (pH, organic C, total N, available K, available P, cation exchange capacity (CEC), and microbial biomass carbon (C)). The more soil enzyme activities there were, the higher the fertility of urban forest soil.
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Beneficial metabolic activities of inflammatory cytokine interleukin 15 in obesity and type 2 diabetes

null

《医学前沿（英文）》 2015年 第9卷 第2期   页码 139-145 doi: 10.1007/s11684-015-0377-z

摘要：

In obesity, chronic inflammation is believed to induce insulin resistance and impairs adipose tissue function. Although this view is supported by a large body of literature, it has been challenged by growing evidence that pro-inflammatory cytokines may favor insulin sensitivity through induction of energy expenditure. In this review article, interleukin 15 (IL-15) is used as a new example to explain the beneficial effects of the pro-inflammatory cytokines. IL-15 is secreted by multiple types of cells including macrophages, neutrophils and skeletal muscle cells. IL-15 expression is induced in immune cells by endotoxin and in muscle cells by physical exercise. Its transcription is induced by transcription factor NF-κB. IL-15 binds to its receptor that contains three different subunits (α, β and γ) to activate JAK/STAT, PI3K/Akt, IKK/NF-κB and JNK/AP1 pathways in cells. In the regulation of metabolism, IL-15 reduces weight gain without inhibiting food intake in rodents. IL-15 suppresses lipogenesis, stimulates brown fat function, improves insulin sensitivity through weight loss and energy expenditure. In human, circulating IL-15 is negatively associated with body weight. In the immune system, IL-15 stimulates proliferation and differentiation of T cells, NK cells, monocytes and neutrophils. In the anti-obesity effects of IL-15, T cells and NK cells are not required, but leptin receptor is required. In summary, evidence from human and rodents supports that the pro-inflammatory cytokine IL-15 may enhance energy expenditure to protect the body from obesity and type 2 diabetes. The mechanism of IL-15 action remains to be fully uncovered in the regulation of energy expenditure.

关键词： inflammation     obesity     cytokine     energy expenditure     insulin resistance    

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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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and mechanism insight on SiC quantum dots sensitized inverse opal TiO with superior photocatalytic activities

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 1913-1924 doi: 10.1007/s11705-023-2350-8

摘要： The combination of SiC quantum dots sensitized inverse opal TiO2 photocatalyst is designed in this work and then applied in wastewater purification under simulated sunlight. From various spectroscopic techniques, it is found that electrons transfer directionally from SiC quantum dots to inverse opal TiO2, and the energy difference between their conduction/valence bands can reduce the recombination rate of photogenerated carriers and provide a pathway with low interfacial resistance for charge transfer inside the composite. As a result, a typical type-II mechanism is proved to dominate the photoinduced charge transfer process. Meanwhile, the composite achieves excellent photocatalytic performances (the highest apparent kinetic constant of 0.037 min–1), which is 6.2 times (0.006 min–1) and 2.1 times (0.018 min–1) of the bare inverse opal TiO2 and commercial P25 photocatalysts. Therefore, the stability and non-toxicity of SiC quantum dots sensitized inverse opal TiO2 composite enables it with great potential in practical photocatalytic applications.

关键词： inverse opal TiO2     silicon carbide quantum dots     quantum dot sensitized photocatalyst     type-II charge transfer route    

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标题 作者 时间 类型 操作

Production of rhamnolipids-producing enzymes of

Kata Kiss,Wei Ting Ng,Qingxin Li

期刊论文

Effect of a new antitranspirant on the physiology and water use efficiency of soybean under different irrigation rates in an arid region

Shasha JI, Ling TONG, Fusheng LI, Hongna LU, Sien LI, Taisheng DU, Youjie WU

期刊论文

Estrogenic activities of di-2-ethylhexyl phthalate

JIN Qiumei, LI Yan, SUN Zengrong

期刊论文

Expression profiles of genes and enzymes related to ascorbic acid metabolism in fruits of

Yingying CHEN,Zhihui ZHAO,Jin ZHAO,Mengjun LIU

期刊论文

Microbial biodegradation of plastics: Challenges, opportunities, and a critical perspective

期刊论文

Biodegradation and detoxification of the triphenylmethane dye coomassie brilliant blue by the extracellular enzymes

Jin Zhao, Qing-Xi Wu, Xiao-Du Cheng, Ting Su, Xiao-Hui Wang, Wen-Na Zhang, Yong-Ming Lu, Yan Chen

期刊论文

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

期刊论文

我国航天的成就与发展

王礼恒

期刊论文

A comparison of the biological activities of ethyl acetate fractions from the stems and leaves of

Zhaolei WANG, Kai JIANG, Qinchao DING, Shujun LIU, Xiaobing DOU, Bin DING

期刊论文

试论人类水事活动的新思维

李佩成

期刊论文

中国航天的发展战略和重点领域

孙来燕

期刊论文

Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

期刊论文

Beneficial metabolic activities of inflammatory cytokine interleukin 15 in obesity and type 2 diabetes

null

期刊论文

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

and mechanism insight on SiC quantum dots sensitized inverse opal TiO with superior photocatalytic activities

期刊论文