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Response of polar regions to emerging organic pollutant organophosphorus esters (OPEs), a review
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作者 CHENG Wenhan BLAIS Jules M. +3 位作者 XIE Zhouqing LIU Yi LI Ming SUN Liguang 《Advances in Polar Science》 2017年第1期13-22,共10页
Polar regions are free from major anthropogenic impact due to their remoteness. However, certain pollutants can be transported there via atmospheric and/or oceanic circulations. Here we present an overview of current ... Polar regions are free from major anthropogenic impact due to their remoteness. However, certain pollutants can be transported there via atmospheric and/or oceanic circulations. Here we present an overview of current research on organophosphorus esters (OPEs) in polar regions by reviewing the literature on distribution, source and transport of OPEs. Current research on OPEs reveals significant anthropogenic influences in both polar regions. As well as the expected occurrence in the Arctic, OPEs were found on the Antarctic lee Sheet up to 650 km from the coast, and the OPE concentrations were higher at high elevation due to cold climate retention. The immediate source of OPEs for inland Antarctica might be the Southern Ocean surrounding the continent, where OPEs in aerosols and seawater showed comparable concentrations to remote areas in the European Arctic. A positive correlation between aerosol OPEs in the open water and the surface vortex of ocean currents indicates that these compounds may be transported and accumulated in the ocean currents. The Antarctica Circumpolar Current accumulates them in the marginal seas of Antarctica. 展开更多
关键词 ANTARCTICA organophosphorus esters Southern Ocean ice sheet
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红海湾海域水产品中有机磷酸酯(OPEs)类阻燃剂污染分析及健康风险评估
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作者 曾以梅 刘奇 +6 位作者 柯常亮 段星星 杨宏亮 黄珂 古小莉 张安凯 陈洁文 《大连海洋大学学报》 CAS CSCD 北大核心 2024年第1期83-91,共9页
为评估有机磷酸酯(organophosphate esters, OPEs)类阻燃剂污染引起的水产品质量安全风险,以广东汕尾红海湾海域近岸养殖和捕捞水产品为研究对象,采用气相色谱三重四级杆串联质谱法(Gas Chromatography-Tandem Mass Spectrometry, GC-MS... 为评估有机磷酸酯(organophosphate esters, OPEs)类阻燃剂污染引起的水产品质量安全风险,以广东汕尾红海湾海域近岸养殖和捕捞水产品为研究对象,采用气相色谱三重四级杆串联质谱法(Gas Chromatography-Tandem Mass Spectrometry, GC-MS/MS)对水产品中10种OPEs含量进行测定。结果表明:红海湾海域养殖水产品中∑10OPEs含量为(55.8±24.2)ng/g(干质量),显著高于捕捞水产品中的含量(20.5 ng/g±20.6 ng/g,干质量)(P<0.05);捕捞水产品中,底栖水产品中∑10OPEs含量(28.4 ng/g±22.6 ng/g,干质量)显著高于中上层水产品中的含量(7.4 ng/g±4.3 ng/g,干质量)(P<0.05);磷酸三(2-丁氧基乙基)酯[tris (2-butoxyethyl) phosphate, TBOEP]、磷酸三正丁酯(tri-n-butyl phosphate, TNBP)、磷酸三(2-氯异丙基)酯[tris (2-chloroisopropyl) phosphate, TCIPP]、磷酸三(2-氯乙基)酯[tris (2-chloroethyl) phosphate, TCEP]和磷酸三苯酯(triphenyl phosphate, TPHP)是红海湾海域水产品检出频率最高的OPEs化合物;养殖水产品和捕捞底栖水产品中主要OPEs污染物组成基本一致,含量最高的OPEs污染物依次为TCEP、TBOEP、TCIPP,而捕捞的中上层水产品中含量最高的OPEs污染物依次为TBOEP、TCIPP、TPHP,暴露评估显示,红海湾海域水产品中OPEs对不同年龄段男性和女性的非致癌风险和致癌风险均低于潜在风险阈值,健康风险可接受。研究表明,OPEs污染在养殖和捕捞水产品中普遍存在,所引起的健康风险水平尚在安全范围内,但随着OPEs消费量的持续增加,由其引起的水产品质量安全风险会越来越高,建议对水产品中OPEs污染情况进行持续跟踪调查。 展开更多
关键词 水产品 有机磷酸酯 风险评估 红海湾 阻燃剂
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Insight into the effect of geographic location and intercropping on contamination characteristics and exposure risk of phthalate esters(PAEs)in tea plantation soils
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作者 Jie Li Shanjie Han +4 位作者 Ruhang Xu Xuchen Zhang Junquan Liang Mengxin Wang Baoyu Han 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第11期3896-3911,共16页
Phthalate esters(PAEs)are an emerging pollutant due to widespread distribution in environmental mediums that have attracted widespread attention over recent years.However,there is little information about tea plantati... Phthalate esters(PAEs)are an emerging pollutant due to widespread distribution in environmental mediums that have attracted widespread attention over recent years.However,there is little information about tea plantation soil PAEs.A total of 270 soil samples collected from 45 tea plantations in the major high-quality tea-producing regions of Jiangsu,Zhejiang,and Anhui provinces in China were analyzed for seven PAEs.The detection frequency of PAEs in tea plantation soil was 100%.DBP,DEHP,and DiBP were the main congeners in tea plantation soil.The PAEs concentrations in the upper soil were significantly higher than those in the lower soil.The concentration of tea plantation soil PAEs in Jiangsu Province was significantly lower than those in Zhejiang and Anhui provinces.Intercropping with chestnuts can effectively reduce the contamination level of PAEs in tea plantation soil.Correlation analysis,redundancy analysis,partial correlation analysis,and structural equation modeling methods further confirmed the strong direct influence of factors such as chestnut–tea intercropping,temperature,and agricultural chemicals on the variation of PAEs in tea plantation soil.The health and ecological risk assessments indicated that non-carcinogenic risk was within a safe range and that there was a high carcinogenic risk via the dietary pathway,with DBP posing the highest ecological risk. 展开更多
关键词 phthalate esters chestnut and tea INTERCROPPING driving factors spatial heterogeneity risk assessment
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Research progress on classification,source,application of phytosterol esters,and their thermal oxidation stability
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作者 Dami Li Shangde Sun Jingnan Chen 《Grain & Oil Science and Technology》 CAS 2024年第1期1-11,共11页
Phytosterol esters can effectively decrease serum cholesterol concentration in the human body and prevent cardio-cerebrovascular diseases.It was found that phytosterol esters exhibited better solubility and bioavailab... Phytosterol esters can effectively decrease serum cholesterol concentration in the human body and prevent cardio-cerebrovascular diseases.It was found that phytosterol esters exhibited better solubility and bioavailability than free phytosterols.In recent years,phytosterol esters have attracted increasing attention.However,during food processing,phytosterol esters are susceptible to degradation at high temperatures,resulting in certain losses and formation of potentially harmful substances for humans.This paper reviews the relevant literatures and updates on the thermal oxidation stability of phytosterol esters in recent years from the following aspects:(i)Sources,physiological activities,and applications of phytosterol esters;(ii)Oxidation mechanism of phytosterol esters;(iii)Effects of phytosterols species,the volume of addition,food matrix,heating temperature and time,and antioxidants on the thermal loss and oxidation stability of phytosterol esters.The research progress on the safety of phytosterol esters is also discussed in detail.Additionally,the prospects for future research are highlighted. 展开更多
关键词 Thermal stability Loss rate Oxidation mechanism Phytosterol esters
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Screening of Degrading Bacteria for Phthalic Acid Esters Under Cadmium Stress and Its Application
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作者 ZHOU Bing-yu ZHOU Yu +2 位作者 WANG Chun-ping LIU Fen LIU Biao 《Agricultural Science & Technology》 CAS 2024年第3期50-56,共7页
In order to enrich the degrading microbial resources for phthalic acid esters(PAEs)under cadmium stress,a degrading bacterium B-7 for di(2-ethylhexyl)phthalate(DEHP)was screened from the strains stored in the laborato... In order to enrich the degrading microbial resources for phthalic acid esters(PAEs)under cadmium stress,a degrading bacterium B-7 for di(2-ethylhexyl)phthalate(DEHP)was screened from the strains stored in the laboratory by means of inorganic salt liquid medium containing DEHP and cadmium,and the characteristics of the strain were studied.Strain B-7 was Bacillus amyloliquefaciens,which had high biosafety and excellent degradability to DEHP.The optimum temperature for degradation was 25–40℃,and the optimum pH value was 6–8.Strain B-7 was cultured in inorganic salt medium(MSM)with an initial DEHP concentration of 400 mg/L and cadmium content of 10 mmol/L for 4 d,and its degradation rate of DEHP was up to 93.1%.In addition,the strain had a strong degradation ability to dimethyl phthalate(DMP),diethyl phthalate(DEP),and dibutyl phthalate(DBP).In soil contaminated by cadmium and DEHP,the synergic degradation of B-7 and indigenous microorganisms in soil significantly increased the degradation rate of DEHP,indicating that this strain had potential application value in the field of microbial remediation of soil contaminated by cadmium and PAEs. 展开更多
关键词 Phthalic acid esters CADMIUM Bacillus amyloliquefaciens Soil bioremediation
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Study on the regulatory effect of liver X receptor in HEK293 cells by six main diterpene esters in Semen Euphorbiae
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作者 Si-Yuan Ma Fan-Miao Kong +8 位作者 Xiao-Tong Wei Jun-Li Zhang Hai-Ting Zhu Xin-Ning Zhang Yu-Feng Hu Ming-Rui Jiang Hui-Nan Wang Yi-Cen Xu Ying-Zi Wang 《TMR Modern Herbal Medicine》 CAS 2024年第2期35-40,共6页
Background:To study the effects of the main diterpene esters in Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)on the transcriptional activity and protein expression of liver X receptor(LXR).Methods:The effe... Background:To study the effects of the main diterpene esters in Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)on the transcriptional activity and protein expression of liver X receptor(LXR).Methods:The effect of the main diterpene ester components in Semen Euphorbiae on the viability of HEK293 cells were studied by MTT assay.The LXR-Luc plasmid vector was transfected into HEK293 cells and treated with Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)for 24 h.The effect of the main diterpene ester components of Semen Euphorbiae on LXR-Luc luciferase activity was investigated by dual luciferase reporter gene system,and the expression of LXRαprotein was detected by Western Blot.Results:Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)could significantly reduce the relative luciferase activity(RLU)of LXRα,and the expression level of LXRαprotein was significantly down-regulated.Conclusion:Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)can inhibit the expression of LXR protein level,which may be achieved by inhibiting the transcriptional activity of LXR. 展开更多
关键词 Semen Euphorbiae diterpene esters HEK293 LXR dual luciferase reporter gene system
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水下舰艇扩频通信体制研究
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作者 李尧 赵健康 龙海辉 《现代电子技术》 北大核心 2025年第1期107-111,共5页
水下舰艇通信采用的水声通信方式在长距离传输中信号衰减严重,且因为隐蔽性需求信号功率受限,叠加受到多径干扰和海洋背景噪声干扰,通信误码率较高。为此,提出水下舰艇扩频通信体制研究。设计扩频通信体制,利用扩频通信体制拓宽传输带宽... 水下舰艇通信采用的水声通信方式在长距离传输中信号衰减严重,且因为隐蔽性需求信号功率受限,叠加受到多径干扰和海洋背景噪声干扰,通信误码率较高。为此,提出水下舰艇扩频通信体制研究。设计扩频通信体制,利用扩频通信体制拓宽传输带宽,提升远距离衰减下的通信信噪比;采用类白噪声的伪随机码m序列和OPS序列作为扩频码组建编码序列集,解决白噪声干扰、多径干扰和码分多址的问题。测试结果表明:同等条件下,采用m序列的扩频通信结果更优,可以实现-25 dB下误码率低于1%的可靠通信。经过该方法调制后,剔除了噪声干扰和多径干扰,增强了衰减的高频信号,解决了水下通信远距离衰减、多径干扰、背景噪声干扰等问题。 展开更多
关键词 水下舰艇通信 扩频通信 M序列 OPS序列 误码率 信噪比
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The diterpenoid esters from Euphorbia lathyris L. induce intestinal inflammation via LXRα/ABCA1-regulated lipid rafts and TLR4-mediated pathway
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作者 Hui-Nan Wang Xiao-Yu Wang +9 位作者 Pei-Hua Wang Ming-Rui Jiang Si-Yuan Ma Hai-Ting Zhu Jun-Li Zhang Xin-Ning Zhang Wen-Jing Chen Yi-Fan Mao Hua Xu Ying-Zi Wang 《Natural Therapy Advances》 CAS 2024年第4期30-37,共8页
Background:Diterpenoid esters are considered to be the main toxic components and bioactive constituents of Euphorbia lathyris L.(EL).Euphorbia factors L1(EF1),L2(EF2),and L3(EF3),the main diterpenoid esters of EL,have... Background:Diterpenoid esters are considered to be the main toxic components and bioactive constituents of Euphorbia lathyris L.(EL).Euphorbia factors L1(EF1),L2(EF2),and L3(EF3),the main diterpenoid esters of EL,have been found to cause intestinal diarrhea and induce intestinal inflammation in mice.This research aimed to explore the effects of major diterpenoid esters from EL on intestinal inflammation,as well as to clarify their possible targets and molecular mechanisms in vivo and vitro.Methods:Caco-2 cells and BALB/c mice were intervened with EFL1,EFL2,and EFL3,respectively.The expressions of TLR4,NLRP3,NF-κB p65,LXRα,ABCA1,TNF-αand IL-1βwere measured by Real-time PCR and ELISA.Cholesterol efflux levels were examined using cholesterol efflux kit.Flow cytometry was applied to detect lipid rafts abundance.Confocal microscopy was applied to investigate co-localization of lipid rafts and TLR4.Results:Our results revealed that EFL1,EFL2,and EFL3 inhibited LXRα,ABCA1 expression,and cholesterol efflux,promoted colocalization of TLR4 and lipid rafts,and up-regulated TLR4,NLRP3,NF-κB p65,TNF-αand IL-1βexpressions.Conclusion:These findings reveal that the mechanisms by which EFL1,EFL2,and EFL3 induce intestinal inflammation may be associated with LXRα/ABCA1-regulated lipid rafts and TLR4-mediated pathways. 展开更多
关键词 diterpenoid esters Euphorbia lathyris L. LXRα/ABCA1 lipid rafts TLR4
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Recent Advances of Sensitive Electrochemical Sensing Platforms for Rapid Detection of Phthalate Acid Esters
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作者 Xiuxiu Dong Lili Zhang +2 位作者 Meicai Ge Minfu Wu Qijian Niu 《Instrumentation》 2024年第2期9-23,共15页
As a kind of plasticizer,phthalic acid esters(PAEs)are often added to plastics to enhance elasticity,transparency,durability and prolong service life.However,it does not chemically bind to plastics and is easy to migr... As a kind of plasticizer,phthalic acid esters(PAEs)are often added to plastics to enhance elasticity,transparency,durability and prolong service life.However,it does not chemically bind to plastics and is easy to migrate to the environment.It is difficult to degrade in the environment,and it is also enriched in the human body through the food chain and respiration,which will lead to obvious adverse reactions such as decreased learning and memory function and neurobehavioral disorders.Due to the toxicity,universality and low concentration limitations of PAEs in the environment and food,it is essential to achieve rapid and sensitive detection of PAEs in soil,atmosphere,water and food.Electrochemical(EC)sensors have the advantages of simplicity,fast,low cost,portability,easy operation,high specificity and high sensitivity,so they are applied for the detection of PAEs.Although there are a large number of studies on the detection of PAEs by EC sensors,there is no review on this aspect.In this review,we introduce the detection of PAEs from classical EC sensors,electrochemiluminescence(ECL)sensors and photo-electrochemical(PEC)sensors in the past five years.This review is beneficial to understanding the construction of EC sensors and the detection mechanism of PAEs.We also propose that the development of rapid,accurate and real-time detection methods of PAEs is key to assessing risk and preventing related diseases. 展开更多
关键词 phthalate acid esters electrochemical sensor DETERMINATION
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基于红外光谱技术对不同间隔年限栽培丹参土壤的红外光谱特征分析
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作者 乔璐 刘永红 +5 位作者 徐可可 余焕英 陈园杰 杨林林 董诚明 王磊 《光谱学与光谱分析》 北大核心 2025年第2期483-491,共9页
植物通过根际分泌物介导根际有益菌和病原菌差异性变化导致的连作障碍是制约丹参栽培发展的主要因素。提出一种基于红外光谱技术结合二维相关光谱的方法,快速检测丹参根际分泌物组成及含量变化。采集同一地区本底土(未种植丹参CK)、正... 植物通过根际分泌物介导根际有益菌和病原菌差异性变化导致的连作障碍是制约丹参栽培发展的主要因素。提出一种基于红外光谱技术结合二维相关光谱的方法,快速检测丹参根际分泌物组成及含量变化。采集同一地区本底土(未种植丹参CK)、正在种植丹参(19-ING)、丹参刚采收(19-ED、23-ED)、轮休1年(23-One)、轮休2年(23-Two)、轮休5年(19-Five)等7种丹参土壤样品的光谱,进行平滑降噪、一阶导数等,提取特征图谱,分析土壤化合物指纹图谱。不同间隔年限栽培丹参土壤的红外光谱峰位和峰形相同,主要差异波段在特征吸收峰3622、3380、1638、995、777、693、524和463 cm^(-1)附近,分别表征酚酸中酚羟基—OH、酯类和有机酸类中羰基C=O、亚甲基、苯环的吸收取代、环状酮类等物质的官能团,轮休1年的土壤在各个特征峰处吸光度增强,表明种植过程中酚酸类、酯类等自毒物质不断积累。不同茬次丹参种植土壤2维相关光谱在波段3750~3600、2170~2145、2060~2030和530~585 cm^(-1)处吸收峰的位置、个数、以及颜色都不相同,清晰地表征出官能团的差异。表明采用红外光谱和2D相关光谱相结合的方法能够实现土壤中有机化合物的快速检测和监测土壤化合物动态变化,为探索丹参连作障碍的形成机理及消减机制提供理论依据。 展开更多
关键词 丹参土壤 中红外光谱 二维红外光谱 酚酸类 酯类
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不同拓扑结构聚(丁二酸丁二醇-对苯二甲酸丁二醇)酯的性能
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作者 殷杰 韩翎 +3 位作者 王珅 贾雪飞 张龙贵 祝桂香 《石油化工》 北大核心 2025年第1期29-34,共6页
通过溶液流延的方式制备了不同拓扑结构带支链的聚(丁二酸丁二醇-对苯二甲酸丁二醇)酯(PBST-Kx)薄膜,利用^(1)H NMR、GPC、TG、DSC、XRD、流变测试等方法对PBST-Kx的结构及性能进行了研究。实验结果表明,支化剂的引入不会影响PBST-Kx分... 通过溶液流延的方式制备了不同拓扑结构带支链的聚(丁二酸丁二醇-对苯二甲酸丁二醇)酯(PBST-Kx)薄膜,利用^(1)H NMR、GPC、TG、DSC、XRD、流变测试等方法对PBST-Kx的结构及性能进行了研究。实验结果表明,支化剂的引入不会影响PBST-Kx分子链的化学组成、热稳定性和结晶性能,但随支化剂官能度的增加,PBST-Kx的支链数增加,Mn呈减小的趋势,分子量分布变宽。支化结构的引入增加了PBST-Kx的熔体黏度,使其具有更高的弹性和更长的松弛时间,且随着支化度的增加而增大。随支化度的增加,PBST-Kx薄膜的拉伸强度和断裂伸长率降低。 展开更多
关键词 拓扑结构 聚(丁二酸丁二醇-对苯二甲酸丁二醇)酯 支化剂 熔体强度
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基于微生物固定化的浓香型白酒无窖泥发酵影响因素研究
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作者 汪江波 荣光玉 +5 位作者 杜彪 朱嘉璐 何超 张瑞景 蔡凤娇 徐健 《酿酒》 2025年第1期67-72,共6页
本实验以丝瓜络为载体,通过固定化窖泥中的功能微生物,从而代替窖泥发酵浓香型白酒。考察了载体添加量、加曲量、发酵时间、载体添加方式等因素对浓香型白酒无窖泥发酵酒醅及酒体中风味物质的影响,并利用冗余分析(redundancy analysis,R... 本实验以丝瓜络为载体,通过固定化窖泥中的功能微生物,从而代替窖泥发酵浓香型白酒。考察了载体添加量、加曲量、发酵时间、载体添加方式等因素对浓香型白酒无窖泥发酵酒醅及酒体中风味物质的影响,并利用冗余分析(redundancy analysis,RDA)方法确定了影响白酒中四大酯含量的主要因素。结果表明,不同因素条件对酒醅的含水率无明显影响,而酸度随着载体添加量、加曲量、发酵时间的增加呈现增加的趋势。在酒体中共检测到79种化合物,其中未添加固定化载体的酒体中检测到26种物质。结合冗余分析发现酒体中己酸乙酯含量与载体添加方式相关性最强,其次是发酵时间。丁酸乙酯与发酵时间呈正相关,而乙酸乙酯与载体添加量和加曲量呈正相关。因此,在后续的生产操作中可以适当调控发酵条件来改善酒体中四大酯的含量。本研究证明了丝瓜络固定复合己酸菌代替窖泥生产浓香型白酒具有实际可行性,为无窖泥发酵浓香型白酒的工艺生产提供了参考。 展开更多
关键词 浓香型白酒 无窖泥发酵 固定化 四大酯 冗余分析
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Anticancer Activities of Substituted Cinnamic Acid Phenethyl Esters on Human Cancer Cell Lines 被引量:4
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作者 李树春 李辉 +2 位作者 张法 李中军 崔景荣 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第4期184-187,共4页
Caffeic acid phenethyl ester (CAPE) and sixteen substituted cinnamic acid phenethyl esters were prepared via conventional procedures in order to test their in vitro anticancer activities by either MTT assay or SRB... Caffeic acid phenethyl ester (CAPE) and sixteen substituted cinnamic acid phenethyl esters were prepared via conventional procedures in order to test their in vitro anticancer activities by either MTT assay or SRB assay on six different human cancer cell lines. The results indicated that in the concentration of 10 μmol·L -1 the lead compound CAPE possessed anticancer activities against human HL 60, Bel 7402, and Hela cell lines, and two other compounds possessed potent anticancer activities against Bel 7402 and Hela cell lines. 展开更多
关键词 medicinal chemistry cinnamic acid phenethyl esters chemical synthesis anticancer activity
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气相色谱-串联质谱法同时测定食用油脂中3-氯丙醇酯和缩水甘油酯
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作者 刘瑶 高彤 +2 位作者 张浩 孙尚德 陈小威 《中国油脂》 北大核心 2025年第2期87-94,共8页
旨在为减控3-氯丙醇酯(3-MCPDE)和缩水甘油酯(GEs)的污染程度和监测其含量变化奠定基础,建立了一种简便、快捷且能同时对食用油脂中3-MCPDE和GEs定性定量分析的检测方法。采用甲醇钠-甲醇溶液对样品进行碱水解反应12min,用正己烷脱脂后... 旨在为减控3-氯丙醇酯(3-MCPDE)和缩水甘油酯(GEs)的污染程度和监测其含量变化奠定基础,建立了一种简便、快捷且能同时对食用油脂中3-MCPDE和GEs定性定量分析的检测方法。采用甲醇钠-甲醇溶液对样品进行碱水解反应12min,用正己烷脱脂后,再用苯基硼酸(PBA)溶液衍生化20min,采用乙酸乙酯提取3次,提取液氮吹至干,用少量乙酸乙酯复溶后,作为待测样液,设置质谱电离能量60eV,进行GC-MS分析。结果表明:建立的方法的平均加标回收率为8870%~92.42%,相对标准偏差(RSD)为2.80%~6.17%,3-MCPDE和GEs分别在40~15000μg/kg和200~15000μg/kg较宽的范围内呈现良好线性关系(R2≥0.9960);该方法准确可靠,与进出口标准(SN/T5220—2019)的检测结果无显著差异;采用该方法对24份常见市售食用油脂的3-MCPDE和GEs污染情况进行分析发现,3-MCPDE的检出率高达95.83%,平均含量为1077.7μg/kg,GEs的检出率为79.17%,平均含量为1074.8μg/kg,且棕榈油和米糠油的3-MCPDE含量和GEs含量远高于其他植物油。该方法具有简便、灵敏度和准确度高等优点,可用于食用油脂中3-MCPDE和GEs的同时测定,另外,急需改善棕榈油和米糠油中3-MCPDE和GEs的污染情况。 展开更多
关键词 食用油脂 3-氯丙醇酯 缩水甘油酯 气相色谱-串联质谱法
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Determination of phthalate esters in fat-containing foods by packed nanofiber solid-phase extraction column and gas chromatography 被引量:2
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作者 邱金丽 王羽 +1 位作者 周小玲 康学军 《Journal of Southeast University(English Edition)》 EI CAS 2016年第3期322-326,共5页
A new method for simultaneous determination of four phthalate esters ( PAEs) in commercial fat-containing foods was developed by the combination of a packed nanofibers column based on solid-phase extraction with gas... A new method for simultaneous determination of four phthalate esters ( PAEs) in commercial fat-containing foods was developed by the combination of a packed nanofibers column based on solid-phase extraction with gas chromatography-flame ionization detector ( GC-FID ). Conditions for obtaining optimum extraction efficiency such as extraction solvents, morphologies of adsorbent, ion strength and pH were investigated and optimized in detail. Under the optimized conditions, the limits of detection (LODs) found for dibutyl phthalate (DBP) , butyl benzyl phthalate (BBP), diethyl hexyl phthalate (DEHP) and di-n-octyl phthalate (DNOP) were 50, 25, 50 and 25 ng/g, respectively. Good linearity of four PAEs was achieved in the range of 50 to 4 000 ng/g. The proposed method was applied for analyzing different kinds of fat-containing samples. PAEs in commercial fat-containing samples can be highly extracted by a packed solid-phase extraction column of 5 mg polystyrene ( PS) nanofibers. The satisfactory average recoveries were obtained in the range of 96. 7% to 102. 3% , and the relative standard deviations (RSDs) below 5% were achieved. The proposed method reduces the organic solvent consumption, the complex and tedious procedures for sample pretreatment, and achieves high sensitivity and reproducibility for the investigated PAEs. 展开更多
关键词 phthalate esters (PAEs nanofibers solid-phase extraction gas chromatography fat-containing foods
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植物油和婴幼儿配方食品中氯丙醇酯和缩水甘油酯研究进展
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作者 朱子翔 肖功年 袁海娜 《中国乳品工业》 北大核心 2025年第1期63-72,共10页
文章介绍了食品中氯丙醇酯和缩水甘油酯的结构与种类、毒理、限量、来源与产生机制、检测方法和污染情况等。氯丙醇酯和缩水甘油酯在食品中的暴露量与植物油的精炼工艺以及所含甘油酯、氯离子等有关,但其累积机制尚不清楚。碱水解过程... 文章介绍了食品中氯丙醇酯和缩水甘油酯的结构与种类、毒理、限量、来源与产生机制、检测方法和污染情况等。氯丙醇酯和缩水甘油酯在食品中的暴露量与植物油的精炼工艺以及所含甘油酯、氯离子等有关,但其累积机制尚不清楚。碱水解过程控制影响氯丙醇酯和缩水甘油酯GC-MS检测方法的准确性和稳定性。氯丙醇酯和缩水甘油酯标准检测方法的进一步完善及在食品中暴露情况的科学评估,以及对食品加工、储运过程中2类污染物累积规律的研究,助力食品中此类污染物的风险防控。 展开更多
关键词 植物油 婴幼儿配方食品 氯丙醇酯 缩水甘油酯
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溶液环境对两种菱镁矿阴离子捕收剂浮选泡沫性能的影响
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作者 徐长明 何东升 +3 位作者 唐远 叶利峰 李智力 付艳红 《工程科学学报》 EI 北大核心 2025年第1期25-32,共8页
浮选体系中浮选泡沫各项性能直接影响其与矿物颗粒间的相互作用.采用DFA 100动态泡沫分析仪,研究了不同pH值和Mg^(2+)环境下磷酸酯盐捕收剂的起泡性能、泡沫稳定性以及泡沫结构等的性能差异,并与传统油酸盐捕收剂进行了对比分析.结果表... 浮选体系中浮选泡沫各项性能直接影响其与矿物颗粒间的相互作用.采用DFA 100动态泡沫分析仪,研究了不同pH值和Mg^(2+)环境下磷酸酯盐捕收剂的起泡性能、泡沫稳定性以及泡沫结构等的性能差异,并与传统油酸盐捕收剂进行了对比分析.结果表明,同为菱镁矿捕收剂,十六烷基磷酸酯钾(CP)捕收剂相较于传统油酸钠(NaOl)捕收剂,在pH值和Mg^(2+)浓度变化时的泡沫适应性更强,且在菱镁矿浮选中显示出更大的优势.具体来说,在相同质量浓度条件下,CP捕收剂溶液表面张力变化相对缓慢,且在所研究pH值和Mg^(2+)浓度范围内均显示相对更适宜的起泡能力和泡沫稳定性,泡沫结构也更稳定.单矿物浮选试验结果表明,菱镁矿上浮率与溶液环境对两种捕收剂泡沫性能的影响结果具有一致性.在pH值小于6.0或Mg^(2+)质量浓度超过30 mg·L^(-1)时,传统NaOl体系中菱镁矿上浮困难,浮选泡沫性能差,而CP体系中菱镁矿上浮率均保持在60%以上.本研究为磷酸酯类捕收剂在菱镁矿浮选中的应用提供了理论依据和实践指导. 展开更多
关键词 浮选 泡沫性能 溶液环境 磷酸酯捕收剂 菱镁矿
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特香型白酒基酒贮存期风味成分平衡过程的解析
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作者 祝云飞 林培 +3 位作者 吴生文 谢芳迁 曾婷婷 蔡珊 《中国酿造》 北大核心 2025年第1期65-72,共8页
以40个陶坛贮存的特香型白酒新基酒为研究对象,每3个月进行检测,跟踪检测2年。基于Pearson相关性分析,从化学反应平衡角度解析基酒总酸/总酯、乳酸/乳酸乙酯、乙酸/乙酸乙酯、己酸/己酸乙酯、丁酸/丁酸乙酯、乙醛/乙缩醛共6组风味成分... 以40个陶坛贮存的特香型白酒新基酒为研究对象,每3个月进行检测,跟踪检测2年。基于Pearson相关性分析,从化学反应平衡角度解析基酒总酸/总酯、乳酸/乳酸乙酯、乙酸/乙酸乙酯、己酸/己酸乙酯、丁酸/丁酸乙酯、乙醛/乙缩醛共6组风味成分在贮存期的相互平衡过程,同时通过配制平衡前后的模拟酒样,分析平衡对基酒感官风味的影响。结果表明,新酒酸酯比值各异,但在贮存过程中差异逐渐变小,酸与对应乙酯的线性相关系数(R2)不断增大,贮存2年相关系数(R2)可达到0.9以上,酸酯比值接近同一数值,达到化学反应平衡。贮存2年白酒酯化浓度商减小量与新酒浓度商具有极显著的正相关性(P<0.01),表明新酒酸酯比值与平衡比值相差越大,平衡速度越快。乙醛与乙缩醛在贮存过程中同步增长,始终保持良好的线性关系。风味成分化学平衡作用可提升酒体的闻香、绵甜感、醇厚感与爽净度。特香型基酒陶坛贮存2年主要风味成分可达到平衡。 展开更多
关键词 白酒 老熟 风味成分 变化规律 酸酯平衡
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肝移植后免疫抑制剂与肠道菌群相互作用的研究进展
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作者 鲁赛娟 宋沧桑 +2 位作者 李兴德 王国徽 毛盼盼 《中国药房》 北大核心 2025年第3期362-366,共5页
免疫抑制剂(包括环孢素、他克莫司、麦考酚酯类药物、糖皮质激素等)是肝移植后预防器官发生排斥反应的首选药物,能够有效地减少宿主对移植物的免疫反应,提高移植成功率,延长患者的生存期。肝移植与肠道生态失调有关,而免疫抑制剂与肠道... 免疫抑制剂(包括环孢素、他克莫司、麦考酚酯类药物、糖皮质激素等)是肝移植后预防器官发生排斥反应的首选药物,能够有效地减少宿主对移植物的免疫反应,提高移植成功率,延长患者的生存期。肝移植与肠道生态失调有关,而免疫抑制剂与肠道菌群之间相互影响——免疫抑制剂的使用会改变肠道菌群的丰度、组成和代谢产物;肠道菌群产生的一系列酶和代谢产物可能会通过化学方式来改变免疫抑制剂的吸收和代谢。另外,肝移植患者术后感染的发生率较高,而肠道菌群会影响炎症因子,免疫抑制剂与炎症因子之间也相互影响。在一定程度上可认为,免疫抑制剂通过肠道菌群在肝移植患者中发挥作用。 展开更多
关键词 免疫抑制剂 肠道菌群 肝移植 他克莫司 环孢素 麦考酚酯 糖皮质激素
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Two New Phenolic Carboxylic Acid Esters from Opuntia vulgaris
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作者 蒋建勤 叶文才 +2 位作者 陈真 楼凤昌 闵知大 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第1期1-3,共3页
Two new phenolic carboxylic acid esters n-butyl eucomate(1) and methyl eucomate (2) and six known compounds eucomic acid(3), 3-β-acetyl-taraxerol (4), friedelin(5),lupenone(6),methyl linoleate(7) and methy... Two new phenolic carboxylic acid esters n-butyl eucomate(1) and methyl eucomate (2) and six known compounds eucomic acid(3), 3-β-acetyl-taraxerol (4), friedelin(5),lupenone(6),methyl linoleate(7) and methyl oleate(8) were isolated from the stems of Opuntia vulgaris Mill(Cactaceae). Their structures were determined on the basis of spectral methods. Compounds 3,4,6,7,8 were isolated for the first time from this plant. 展开更多
关键词 Opuntia vulgaris Phenolic carboxylic acid ester n-Butyl eucomate Methyl eucomate
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