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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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Discovery of novel ursolic acid derivatives as effective antimicrobial agents through a ROS-mediated apoptosis mechanism

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 2101-2113 doi: 10.1007/s11705-023-2361-5

摘要： In response to the reduction of food production and economic losses caused by plant bacterial diseases, it is necessary to develop new, efficient, and green pesticides. Natural products are rich and sustainable source for the development of new pesticides due to their low toxicity, easy degradation, and eco-friendliness. In this study, we prepared three series of ursolic acid derivatives and assessed their antibacterial ability. Most target compounds exhibited outstanding antibacterial activities. Among them, the relative optimal EC50 values of Xanthomonas oryzae pv. oryzae and Xanthomonas axonopodis pv. citri were 2.23 (A17) and 1.39 (A16) μg·mL–1, respectively. The antimicrobial mechanism showed that compound A17 induced an excessive accumulation and production of reactive oxygen species in bacteria and damaged the cell membrane integrity to kill bacteria. More interestingly, the addition of low concentrations of exogenous hydrogen peroxide enhanced the antibacterial efficacy of compound A17 against Xanthomonas oryzae pv. oryzae. These entertaining results suggested that compound A17 induced an apparent apoptotic behavior in the tested bacteria. Overall, we developed the promising antimicrobial agents that destroyed the redox system of phytopathogenic bacteria, further demonstrating the unprecedented potential of ursolic acid for agricultural applications.

关键词： ursolic acid     antibacterial activities     reactive oxygen species     apoptosis    

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Antibacterial properties of extracts of

Manhong YE,Lei ZHANG,Jiaqi GE,Haifeng SUN,Jingjing NI,Shengmei YANG,Wanhong WEI

《农业科学与工程前沿（英文）》 2015年 第2卷 第4期   页码 327-334 doi: 10.15302/J-FASE-2015078

摘要： Canadian goldenrod ( ) is one of the most destructive invasive weeds in South-eastern China. To evaluate its potential application as dietary supplement in red swamp crayfish ( ), the antibacterial properties of aqueous and ethanol extracts of this plant against three major pathogenic bacteria in crayfish aquaculture were examined. Inhibition zone tests and determination of minimum inhibitory concentration revealed that the extracts had lower antibacterial activity than extracts from two traditional medicinal plants that possess antibacterial properties, garlic ( ) and cortex phellodendri ( ). However, they did exhibit greater antibacterial effects than extracts from another widely used medicinal plant, , and an aquatic weed, . Aqueous extracts of Canadian goldenrod gave greater inhibition than the ethanol extracts. Crayfish fed a diet with 2% these aqueous extracts exhibited significantly higher enzyme activity of alkaline phosphatase, catalase and phenoloxidase ( <0.05). Based on the results of this study, we conclude that aqueous extracts of Canadian goldenrod are highly promising for the development of new dietary supplement for use in crayfish aquaculture.

关键词： antibacterial activity     Canadian goldenrod     antioxidant enzyme     crayfish    

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Evaluation of 1,4-naphthoquinone derivatives as antibacterial agents: activity and mechanistic studies

《环境科学与工程前沿（英文）》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1631-2

摘要：

● All 1,4-naphthoquinone hybrids exhibited significant antimicrobial activity.

关键词： 1     4-naphthoquinone derivatives     Antibacterial     Action mechanism     RecA    

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Nano-copper ions assembled cellulose-based composite with antibacterial activity for biodegradable personal

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1544-1554 doi: 10.1007/s11705-022-2288-2

摘要： The current SARS-CoV-2 pandemic has resulted in the widespread use of personal protective equipment, particularly face masks. However, the use of commercial disposable face masks puts great pressure on the environment. In this study, nano-copper ions assembled cotton fabric used in face masks to impart antibacterial activity has been discussed. To produce the nanocomposite, the cotton fabric was modified by sodium chloroacetate after its mercerization, and assembled with bactericidal nano-copper ions (about 10.61 mg·g–1) through electrostatic adsorption. It demonstrated excellent antibacterial activity against Staphylococcus aureus and Escherichia coli because the gaps between fibers in the cotton fabric allow the nano-copper ions to be fully released. Moreover, the antibacterial efficiency was maintained even after 50 washing cycles. Furthermore, the face mask constructed with this novel nanocomposite upper layer exhibited a high particle filtration efficiency (96.08% ± 0.91%) without compromising the air permeability (28.9 min·L–1). This green, economical, facile, and scalable process of depositing nano-copper ions onto modified cotton fibric has great potential to reduce disease transmission, resource consumption, and environmental impact of waste, while also expanding the range of protective fabrics.

关键词： cellulose-based     nanocomposite     biodegradable antibacterial fabric     nano-copper ions     face masks    

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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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Waterborne Poly(Vanillin-Butyl Acrylate)/MXene Coatings for Leather with Desired Warmth Retention and Antibacterial

Jianzhong Ma,Li Ma,Lei Zhang,Wenbo Zhang,Qianqian Fan,Buxing Han,

《工程（英文）》 doi: 10.1016/j.eng.2023.06.005

摘要： This study presents a solvent-free, facile synthesis of a bio-based green antibacterial agent and aromatic monomer methacrylated vanillin (MV) using vanillin. The resulting MV not only imparted antibacterial properties to coatings layered on leather, but could also be employed as a green alternative to petroleum-based carcinogen styrene (St). Herein, MV was copolymerized with butyl acrylate (BA) to obtain waterborne bio-based P(MV–BA) miniemulsion via miniemulsion polymerization. Subsequently, MXene nanosheets with excellent photothermal conversion performance and antibacterial properties, were introduced into the P(MV–BA) miniemulsion by ultrasonic dispersion. During the gradual solidification of P(MV–BA)/MXene nanocomposite miniemulsion on the leather surface, MXene gradually migrated to the surface of leather coatings due to the cavitation effect of ultrasonication and amphiphilicity of MXene, which prompted its full exposure to light and bacteria, exerting the maximum photothermal conversion efficiency and significant antibacterial efficacy. In particular, when the dosage of MXene nanosheets was 1.4 wt%, the surface temperature of P(MV–BA)/MXene nanocomposite miniemulsion-coated leather (PML) increased by about 15 °C in an outdoor environment during winter, and the antibacterial rate against Escherichia coli and Staphylococcus aureus was nearly 100% under the simulated sunlight treatment for 30 min. Moreover, the introduction of MXene nanosheets increased the air permeability, water vapor permeability, and thermal stability of these coatings. This study provides a new insight into the preparation of novel, green, and waterborne bio-based nanocomposite coatings for leather, with desired warmth retention and antibacterial properties. It can not only realize zero-carbon heating based on sunlight in winter, reducing the use of fossil fuels and greenhouse gas emissions, but also improve ability to fight off invasion by harmful bacteria, viruses, and other microorganisms.

关键词： MXene nanosheets     Vanillin     Styrene substitute     Leather coating     Photothermal conversion     Warmth retention     Antibacterial properties    

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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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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

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

Discovery of novel ursolic acid derivatives as effective antimicrobial agents through a ROS-mediated apoptosis mechanism

期刊论文

Antibacterial properties of extracts of

Manhong YE,Lei ZHANG,Jiaqi GE,Haifeng SUN,Jingjing NI,Shengmei YANG,Wanhong WEI

期刊论文

Evaluation of 1,4-naphthoquinone derivatives as antibacterial agents: activity and mechanistic studies

期刊论文

Nano-copper ions assembled cellulose-based composite with antibacterial activity for biodegradable personal

期刊论文

Estrogenic activities of di-2-ethylhexyl phthalate

JIN Qiumei, LI Yan, SUN Zengrong

期刊论文

Waterborne Poly(Vanillin-Butyl Acrylate)/MXene Coatings for Leather with Desired Warmth Retention and Antibacterial

Jianzhong Ma,Li Ma,Lei Zhang,Wenbo Zhang,Qianqian Fan,Buxing Han,

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

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