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Contamination of Phthalate Esters in Vegetable Agriculture and Human Cumulative Risk Assessment

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Pedosphere 2017年第3期27卷 439-451页

作者： CHEN Ning shuai wenjuan HAO Xinmei ZHANG Huichun ZHOU Dongmei GAO Juan Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Sciences University of Chinese Academy of Sciences College of Water Resources and Civil Engineering China Agricultural University Department of Civil and Environmental Engineering Temple University

Phthalate esters(PAEs), which can disturb human endocrine system, have been widely detected in vegetable greenhouse agriculture in China. To investigate the effects of environmental factors on PAEs in soils, pollution sources were identified, and the cumulative risks of PAEs to humans through vegetables in the diet were evaluated in this study. Ninety-eight vegetable samples were collected from 10 markets along with 128 vegetable and 111 soil samples from agricultural greenhouses and open field. All soil and vegetable samples were contaminated with PAEs, and the total concentrations of the 5 PAEs, including dimethyl phthalate(DMP), diethyl phthalate(DEP), di-iso-butyl phthalate(DiBP), di-n-butyl phthalate(DnBP), and di-2-ethylhexyl phthalate(DEHP), were in the ranges of 0.26–2.53 mg kg^(-1) for soils and 0.95–8.09 mg kg^(-1) for vegetables. Three components extracted from principle component analysis could explain 51.2%, 19.8%, and 15.3% of the total variance of the 5 PAEs in soils, which may represent three major sources of PAEs, i.e., wastewater irrigation, application of fertilizers and pesticides, and plastic film. Long-term greenhouse cultivation could accumulate DEHP in soils, and a higher soil Fe Ox content reduced the Dn BP concentration. Based on a survey of vegetables in the diet, the hazard index of PAEs was < 0.15 for individuals in different cities. The exposure of PAEs through vegetable intake was higher than the total exposure from other food stuffs, inhalation, and dermal absorption. More attention should be given to controlling PAEs in greenhouse vegetables.

关键词：邻苯二甲酸酯类蔬菜大棚危险性评价农药污染农业大棚累积风险邻苯二甲酸二丁酯邻苯二甲酸二异辛酯

厌氧环境下黏土矿物结构Fe(Ⅲ)还原对Cd(Ⅱ)固持特性的影响

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农业环境科学学报 2024年第5期43卷 1045-1055页

作者：范小妹董易坤吴聪王帅廖文娟周卫军崔浩杰湖南农业大学资源学院长沙410128

黏土矿物结构Fe(Ⅲ)是土壤铁元素主要赋存形态之一,稻田淹水环境下矿物结构Fe(Ⅲ)易发生还原反应,改变矿物晶体微结构和表面化学性质,为研究这种变化对矿物固持Cd(Ⅱ)特性的影响,以合成含铁黏土矿物绿脱石为研究对象,通过化学还原,探讨... 详细信息

黏土矿物结构Fe(Ⅲ)是土壤铁元素主要赋存形态之一,稻田淹水环境下矿物结构Fe(Ⅲ)易发生还原反应,改变矿物晶体微结构和表面化学性质,为研究这种变化对矿物固持Cd(Ⅱ)特性的影响,以合成含铁黏土矿物绿脱石为研究对象,通过化学还原,探讨了厌氧条件下绿脱石结构态Fe(Ⅲ)还原对Cd(Ⅱ)吸附性能的影响及作用机制。结果表明:合成绿脱石中总铁含量为31.3%,结构态Fe(Ⅱ)和Fe(Ⅲ)的含量占总铁的98.6%。还原处理后,矿物结构中Fe(Ⅱ)含量由还原前的3.9%显著提高至67.4%。XRD、SEM、BET和XPS分析表明,还原后绿脱石矿物层间距增大,分散程度更高,比表面积由151.6 m^(2)·g^(-1)增加至184.0 m^(2)·g^(-1),矿物表面的羟基基团数量增加。结构Fe(Ⅲ)还原降低了矿物对Cd(Ⅱ)的吸附和固持性能,Langmuir模型拟合还原后矿物对Cd(Ⅱ)的最大吸附量为23.5 mg·g-1,明显低于还原前矿物对Cd(Ⅱ)的吸附量(33.4 mg·g-1)。还原前后矿物对Cd(Ⅱ)的吸附性能均随着离子强度增大而降低,但还原矿物吸附Cd(Ⅱ)的降幅明显低于未还原矿物。黏土矿物结构Fe(Ⅲ)还原后吸附Cd(Ⅱ)的性能降低主要是由于还原过程中结构Fe(Ⅱ)迁移进入层间,抑制了吸附过程中Cd(Ⅱ)进入矿物层间。研究表明,厌氧环境中黏土矿物结构Fe(Ⅲ)显著降低了矿物对Cd(Ⅱ)的固持特性。

关键词：黏土矿物结构态铁还原镉吸附

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荨麻多糖提取及其对HepG_(2)细胞的降糖作用研究

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食品与发酵工业 2024年第2期50卷 23-33页

作者：杨文娟帅召瑞龚频姚文博李楠张嘉园程世蕊陕西科技大学食品科学与工程学院陕西西安710021

该文以荨麻为原材料,通过单因素试验和响应面试验优化半仿生提取荨麻多糖工艺。采用α-葡萄糖苷酶和α-淀粉酶抑制实验,测定荨麻多糖的降糖作用。通过构建胰岛素抵抗HepG_(2)细胞(insulin resistant HepG_(2),IR-HepG_(2))模型,测定甘... 详细信息

该文以荨麻为原材料,通过单因素试验和响应面试验优化半仿生提取荨麻多糖工艺。采用α-葡萄糖苷酶和α-淀粉酶抑制实验,测定荨麻多糖的降糖作用。通过构建胰岛素抵抗HepG_(2)细胞(insulin resistant HepG_(2),IR-HepG_(2))模型,测定甘油三酯(triglyceride,TG)、己糖激酶(hexokinase,HK)、丙酮酸激酶(pyruvate kinase,PK)、糖原含量来探讨荨麻多糖的降糖作用。结果表明,当pH_(1)3、pH_(2)8、料液比1∶16(g∶mL)、提取温度65℃、提取时间77 min时,荨麻多糖的得率为7.04%。α-葡萄糖苷酶和α-淀粉酶抑制实验表明,荨麻多糖可通过抑制α-葡萄糖苷酶和α-淀粉酶来表现降糖作用。细胞实验表明,荨麻多糖可通过影响IR-HepG_(2)细胞的葡萄糖消耗来减轻胰岛素抵抗;通过提高HK、PK含量,促进糖原合成,降低TG含量来调节糖脂代谢,从而发挥降糖作用。综上所述,荨麻多糖具有较强降糖活性,为将其应用于糖尿病患者辅助功能食品提供理论依据。

关键词：荨麻多糖工艺优化 HepG_(2)细胞降糖作用

ZnNb_(2)O_(6)掺杂BNT基无铅弛豫铁电体陶瓷的性能研究

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人工晶体学报 2024年第1期53卷 154-162页

作者：肖齐龙王世宇蒋芮梅雄峰吴昊石亚军孙帅吴文娟成都信息工程大学光电工程学院成都610025

利用传统固相法制备了0.7(Na_(0.5)Bi_(0.5))TiO_(3)-0.3(Sr_(0.7)Bi_(0.2))TiO_(3)-xZnNb_(2)O_(6)(缩写为BNT-SBT-xZN,其中x=0.5%、1.0%、1.5%和2.0%(摩尔分数))陶瓷,并研究了引入ZnNb2O6对BNT基陶瓷材料的结构和性能的影响规律。结果表明:少量ZnNb_(2)O_(6)掺杂(x=0.5%时)的BNT-SBT-xZN陶瓷具有纯的钙钛矿结构,且微观结构致密,无第二相,在室温时为典型的弛豫铁电体(弥散指数γ>1.7),极化前后样品的铁电-弛豫转变温度(TR-E)均低于室温,而与三方相R3c和四方相P4bm的纳米极性微区(PNRs)热弛豫有关的介电反常出现在TR-E<100℃;当ZnNb_(2)O_(6)含量增多时,遍历弛豫态逐渐起主导作用,最大极化强度(Pmax)和剩余极化强度(Pr)均出现减小趋势。综合来看,x=0.5%的BNT-SBT-xZN陶瓷具有高的Pmax、低的Pr、大的ΔP,并具备良好的储能特性及频率和温度稳定性,在室温电场强度为110 kV/cm时,Pmax=44.7μC/cm^(2),Pr=12.4μC/cm^(2),ΔP=32.3μC/cm^(2),储能密度W1=1.066 J/cm^(3),储能效率η=48.68%。此外,x=0.5%的BNT-SBT-xZN陶瓷在100 kV/cm的电场强度下充放电性能良好,放电能量密度Wd=0.60 J/cm^(3),最大放电电流Imax=45.33 A,电流密度CD=1443 A/cm^(2),功率密度PD=72.2 MW/cm^(3)。

关键词： BNT基陶瓷弛豫铁电体 ZnNb_(2)O_(6) 介电性能铁电性能储能特性

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黑龙江省东部珍子山组的沉积环境与聚煤特征

黑龙江科技大学学报 2024年第2期34卷 244-248页

作者：张金彪王帅王文娟窦德胜黑龙江省自然资源调查院哈尔滨150000 辽宁工程技术大学矿业学院辽宁阜新123032 黑龙江科技大学矿业工程学院哈尔滨150022

为全面认识黑龙江省东部珍子山组含煤岩系沉积体系、沉积环境的平面和垂向展布特征以及聚煤特征。采用地质剖面观察及钻孔岩心描述等方法,结合岩石薄片分析,研究了黑龙江东部晚石炭世-早二叠世珍子山组含煤地层的沉积环境和聚煤特征。... 详细信息

为全面认识黑龙江省东部珍子山组含煤岩系沉积体系、沉积环境的平面和垂向展布特征以及聚煤特征。采用地质剖面观察及钻孔岩心描述等方法,结合岩石薄片分析,研究了黑龙江东部晚石炭世-早二叠世珍子山组含煤地层的沉积环境和聚煤特征。结果表明:珍子山组岩相类型以砂岩相和黏土岩相为主,沉积环境主要为河流相、滨浅湖相和泥炭沼泽相;厚煤层主要形成在滨浅湖相,位于高位体系域早期和晚期。

关键词：沉积环境聚煤规律珍子山组

Identification of niclosamide as a novel antiviral agent against porcine epidemic diarrhea virus infection by targeting viral internalization

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Virologica Sinica 2023年第2期38卷 296-308页

作者： Yue Wang Huimin Huang Dongliang Li Chenxu Zhao shuai Li Panpan Qin Yaqin Li Xia Yang wenjuan Du Wentao Li Yongtao Li College of Veterinary Medicine Henan Agricultural UniversityZhengzhou450002China State Key Laboratory of Agricultural Microbiology College of Veterinary MedicineHuazhong Agricultural UniversityWuhan430070China Faculty of Veterinary Medicine Utrecht UniversityUtrecht3584 CLthe Netherlands Hubei Hongshan Laboratory Wuhan430070China

Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a recombinant PEDV expressing renilla luciferase(PEDV-Rluc)to screen potential anti-PEDV agents from an FDAapproved drug library in Vero cells.Four compounds were identified that significantly decreased luciferase activity of PEDV-Rluc.Among them,niclosamide was further characterized because it exhibited the most potent antiviral activity with the highest selectivity index.It can efficiently inhibit viral RNA synthesis,protein expression and viral progeny production of classical and variant PEDV strains in a dose-dependent manner.Time of addition assay showed that niclosamide exhibited potent anti-PEDV activity when added simultaneously with or after virus infection.Furthermore,niclosamide significantly inhibited the entry stage of PEDV infection by affecting viral internalization rather than viral attachment to cells.In addition,a combination with other small molecule inhibitors of endosomal acidification enhanced the anti-PEDV effect of niclosamide in vitro.Taken together,these findings suggested that niclosamide is a novel antiviral agent that might provide a basis for the development of novel drug therapies against PEDV and other related pathogenic coronavirus infections.

关键词： Coronavirus Porcine epidemic diarrhea virus(PEDV) Niclosamide(NIC) Antiviral Virus entry Endocytosis Host-targeted antivirals

Development of fluorine-substituted NH_(2)-biphenyl-diarylpyrimidines as highly potent non-nucleoside reverse transcriptase inhibitors:Boosting the safety and metabolic stability

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Acta Pharmaceutica Sinica B 2023年第3期13卷 1192-1203页

作者： Xin Jin shuai Wang Limin Zhao wenjuan Huang Yinxiang Zhang Christophe Pannecouque Erik De Clercq Ge Meng Huri Piao Fener Chen Engineering Center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433China Key Laboratory of Natural Resources of Changbai Mountain&Functional Molecules Ministry of EducationCollege of PharmacyYanbian UniversityYanji 133002China Rega Institute for Medical Research KU LeuvenLeuven B-3000Belgium

Our recent studies for nonnucleoside reverse transcriptase inhibitors identified a highly potent compound JK-4b against WT HIV-1(EC_(50)=1.0 nmol/L),but the poor metabolic stability in human liver microsomes(t_(1/2)=14.6 min)and insufficient selectivity(SI=2059)with high cytotoxicity(CC_(50)=2.08μmol/L)remained major issues associated with JK-4b.The present efforts were devoted to the introduction of fluorine into the biphenyl ring of JK-4b,leading to the discovery of a novel series of fluorine-substituted NH_(2)-biphenyl-diarylpyrimidines with noticeable inhibitory activity toward WT HIV-1 strain(EC_(50)=1.8–349 nmol/L).The best compound 5t in this collection(EC_(50)=1.8 nmol/L,CC_(50)=117μmol/L)was 32-fold in selectivity(SI=66,443)compared to JK-4b and showed remarkable potency toward clinically multiple mutant strains,such as L100I,K103N,E138K,and Y181C.The metabolic stability of 5t was also significantly improved(t_(1/2)=74.52 min),approximately 5-fold higher than JK-4b in human liver microsomes(t_(1/2)=14.6 min).Also,5t possessed good stability in both human and monkey plasma.No significant in vitro inhibition effect toward CYP enzyme and hERG was observed.The single-dose acute toxicity test did not induce mice death or obvious pathological damage.These findings pave the way for further development of 5t as a drug candidate.

关键词： HIV-1 NNRTI DAPYs Safety Metabolic stability

Most root-derived carbon inputs do not contribute to long-term global soil carbon storage

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Science China Earth Sciences 2023年第5期66卷 1072-1086页

作者： Guocheng WANG Liujun XIAO Ziqi LIN Qing ZHANG Xiaowei GUO Annette COWIE shuai ZHANG Mingming WANG Songchao CHEN Ganlin ZHANG Zhou SHI wenjuan SUN Zhongkui LUO Institute of Agriculture Remote Sensing and Information Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou310058China LAPC Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China School of Atmospheric Sciences Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSun Yat-sen UniversityZhuhai519082China New South Wales Department of Primary Industries University of New EnglandArmidaleNSW2351Australia State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing210008China Academy of Ecological Civilization Zhejiang UniversityHangzhou310058China Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationZhejiang UniversityHangzhou310058China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Key Laboratory of Agricultural Remote Sensing and Information System Zhejiang ProvinceHangzhou310058China

Plant root-derived carbon(C)inputs(I_(root))are the primary source of C in mineral bulk soil.However,a fraction of I_(root)may lose quickly(I_(loss),e.g.,via rhizosphere microbial respiration,leaching and fauna feeding)without contributing to long-term bulk soil C storage,yet this loss has never been quantified,particularly on a global scale.In this study we integrated three observational global data sets including soil radiocarbon content,allocation of photo synthetically assimilated C,and root biomass distribution in 2,034 soil profiles to quantify I_(root)and its contribution to the bulk soil C pool.We show that global average I_(root)in the 0-200 cm soil profile is 3.5 Mg ha^(-1)yr^(-1),~80%of which(i.e.,I_(loss))is lost rather than co ntributing to long-term bulk soil C storage.I_(root)decreases exponentially with soil depth,and the top 20 cm soil contains>60%of total I_(root).Actual C input contributing to long-term bulk soil storage(i.e.,I_(root)-I_(loss))shows a similar depth distribution to I_(root).We also map I_(loss)and its depth distribution across the globe.Our results demonstrate the global significance of direct C losses which limit the contribution of I_(root)to bulk soil C storage;and provide spatially explicit data to facilitate reliable soil C predictions via separating direct C losses from total root-derived C inputs.

关键词： Carbon inputs Root biomass Soil organic carbon Depth distribution Bulk soil carbon Radiocarbon

溶剂调控的α-芳基α-重氮酯与2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)的去重氮化氧合反应

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有机化学 2022年第9期42卷 2814-2822页

作者：贾润红刘帅王世超郝文娟姜波连云港师范高等专科学校初等教育学院江苏连云港222006 江苏师范大学化学与材料科学学院江苏徐州221116

报道了一类新型无金属、溶剂调控的2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)与α-芳基α-重氮酸酯的去重氮化氧合反应.当反应使用二氯甲烷作溶剂时, DDQ与α-芳基α-重氮酯以物质的量比1∶2发生双去重氮化氧氢键插入反应,得到α,α’-(1,4-... 详细信息

报道了一类新型无金属、溶剂调控的2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)与α-芳基α-重氮酸酯的去重氮化氧合反应.当反应使用二氯甲烷作溶剂时, DDQ与α-芳基α-重氮酯以物质的量比1∶2发生双去重氮化氧氢键插入反应,得到α,α’-(1,4-苯二氧基)二酯衍生物为主要产物,而使用1,2-二氯乙烷时,该反应底物以物质的量比2∶3进行反应,经双去重氮化氧氢键插入和去重氮化双氧合反应串联过程合成了一系列结构复杂的α,α-双芳氧基酯衍生物,收率中等至良好.控制实验证实了氧氢插入过程中的氢元素来自于溶剂中的水分子.此外,该反应无需金属催化剂,具有条件温和、操作简便以及化学选择性可控等优点.

关键词：氧合反应去重氮化反应化学选择性分叉合成