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Direct conversion of furfural to levulinic acid/ester in dimethoxymethane:Understanding the mechanism for polymerization 被引量:3
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作者 Yuewen Shao Xun Hu +7 位作者 Zhanming Zhang Kai Sun Guanggang Gao Tao Wei Shu Zhang Song Hu Jun Xiang Yi Wang 《Green Energy & Environment》 SCIE CSCD 2019年第4期400-413,共14页
This study investigated the conversion of furfural to 5-hydroxymethylfurfural(HMF)and further to levulinic acid/ester in dimethoxymethane under acidic conditions,with the particular focus on understanding the mechanis... This study investigated the conversion of furfural to 5-hydroxymethylfurfural(HMF)and further to levulinic acid/ester in dimethoxymethane under acidic conditions,with the particular focus on understanding the mechanism for polymer formation.The results showed that furfural could react with dimethoxymethane via electrophilic substitution reaction to form HMF or the ether/acetal of HMF,which were further converted to levulinic acid and methyl levulinate.The polymerization of furfural and the cross-polymerization between dimethoxymethane and the levulinic acid/ester produced were the main side reactions leading to the decreased yields of levulinic acid/ester.Comparing to the other solvent,methanol as the co-solvent helped to alleviate but not totally inhibited the occurrences of the polymerization,as the polymerization reactions via aldol condensation did not eliminate the C=O functionalities.As a consequence,the polymerization reactions continued to proceed.Other co-solvent used such as guaiacol,dimethyl sulfoxide and acetone interfered with the transformation of furfural to HMF or aided the polymerization reactions.The polymer produced from the reactions between furfural and DMM was different from that produced from levulinic acid/ester.The former had a higher crystallinity,while the latter was more aliphatic.The DRIFTS and TG-MS studies showed that the polymer had the carboxylic group,methyl group and the aliphatic structure in the skeleton.The removal of these functionalities was accompanied by the aromatization of the polymer.The condensation of DMM with levulinic acid/ester was the key reason for the diminished production of levulinic acid/ester. 展开更多
关键词 FURFURAL DIMETHOXYMETHANE Levulinic acid/ester Mechanism for polymerization Properties of the polymer
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Accumulation characteristics and fate modeling of phthalic acid esters in surface water from the Three Gorges Reservoir area,China 被引量:2
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作者 Shuai Sun Bing Zhang +6 位作者 Junjie Hu Wen Gu Zhen Wang Deling Fan Feng Ge Lili Shi Lei Wang 《Journal of Environmental Sciences》 2025年第3期46-56,共11页
Phthalic acid esters(PAEs)are a group of compounds widespread in the environment.To investigate the occurrence and accumulation characteristics of PAEs,surface water samples were collected from the Three Gorges Reserv... Phthalic acid esters(PAEs)are a group of compounds widespread in the environment.To investigate the occurrence and accumulation characteristics of PAEs,surface water samples were collected from the Three Gorges Reservoir area,China.The total concentrations of∑_(11)analyzed PAEs(11PAEs)in the collected water samples ranging from 197.7 to 1,409.3 ng/L(mean±IQR:583.1±308.4 ng/L).While DEHP was the most frequently detected PAE,DnBP and DnNP were the most predominant PAEs in the analyzed water samples with a mean contribution of 63.3%of the∑_(11)PAEs.The concentrations of the∑_(11)PAEs in the water samples from the upper reaches of the Yangtze River were significantly higher than those from themiddle reaches.To better understand the transport and fate of the PAEs,seven detected PAEs were modeled by Quantitative Water Air Sediment Interaction(QWASI).The simulated and measured values were close for most PAEs,and differences are within one order of magnitude even for the worst one.For all simulated PAEs,water and particle inflow were main sources in the reservoir,whereas water outflow and degradation in water were important removal pathways.The contribution ratios of different sources/losses varied fromPAEs,depending on their properties.The calculated risk quotients of DnNP in the Three Gorges Reservoir area whether based onmonitoring or simulating results were all far exceeded the safety threshold value,implying the occurrence of this PAE compound may cause potential adverse effects for the aquatic ecology of the Three Gorges Reservoir area. 展开更多
关键词 Phthalic esters Surface water Transport and fate Three Gorges Reservoir area Risk assessment
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Nickel-catalyzed electrochemical carboxylation of propargylic esters with CO_(2) to 2,3-allenoic acids
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作者 Yuqing Zhong Mengmeng Jiang +4 位作者 Deyong Yang Nan Feng Ying Sun Huimin Wang Feng Zhou 《Chinese Chemical Letters》 2025年第12期218-223,共6页
Here,we report a novel nickel-catalyzed electrochemical carboxylation of propargylic esters with CO_(2),characterized by the regioselective synthesis of 2,3-allenoic acids rather than propargylic carboxylic acids.Both... Here,we report a novel nickel-catalyzed electrochemical carboxylation of propargylic esters with CO_(2),characterized by the regioselective synthesis of 2,3-allenoic acids rather than propargylic carboxylic acids.Both acyclic propargylic esters and cyclic propargylic carbonates serve as effective substrates,facilitating the synthesis of mono-,di-,tri-,and tetra-substituted 2,3-allenoic acids with broad substrate scope under mild conditions.Mechanistic investigations indicate that the in situ generated Ni(Ⅰ)complex might serve as the active species to react with propargylic esters,forming the allenyl-Ni(Ⅰ)complex under electroreductive conditions.A possible γ-selective nucleophilic attack of allenyl-Ni(Ⅰ)complex on CO_(2) is likely involved in the formation of the desired 2,3-allenoic acids. 展开更多
关键词 CO_(2) Nickel-catalysis Electro-carboxylation Propargylic esters 2 3-Allenoic acids
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Using degrading endophytic bacteria to detoxify the phthalic acid esters in crops from contaminated soil
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作者 Xiangyu Liu Xiangrui Du +4 位作者 Xiangzhi Zuo Zeming Wang Bozena Czech Patryk Oleszczuk Yanzheng Gao 《Journal of Environmental Sciences》 2025年第11期378-390,共13页
Phthalic acid esters(PAEs)are widely released into the environment due to industrial and agricultural activities.This poses significant risks,not only to crops grown on contaminated soil but also to humans.PAEs enter ... Phthalic acid esters(PAEs)are widely released into the environment due to industrial and agricultural activities.This poses significant risks,not only to crops grown on contaminated soil but also to humans.PAEs enter the human body through the food chain,causing potential health hazards.Endophytic bacteria have demonstrated a significant potential as effective bioremediation agents,with specialized mechanisms of PAEs degradation.Endophytic bacteria such as Rhodococcus,Pseudomonas and Sphingomona recognize root exudates,adhere to and penetrate root surfaces,and ultimately colonize crops.They form symbiotic relationships with crops,obtaining nutrients and habitats from crops,meanwhile,promoting plant growth and health through hormone production,nutrient regulation,and the suppression of pathogenic microorganisms.Furthermore,endophytic bacteria efficiently degrade PAEs in soil-crop systems through synergistic interactions with indigenous rhizosphere microflora and regulatory effects on enzyme activity in crops.Here,we review the role of endophytic bacteria in the bioremediation of PAEs-contaminated crops and soils.In addition,we discuss the scarcity of endophytic bacterial strains with a confirmed ability to degrade PAEs,and underscore the lack of the research on the mechanisms of PAEs degradation by these bacteria.This review also points out that future study should investigate the molecular mechanisms underlying the interaction between endophytic bacteria and PAEs to offer novel insights and solutions for environmental protection and sustainable agricultural development. 展开更多
关键词 Phthalic acid esters Endophytic bacteria COLONIZATION Plant growth promotion Degradative mechanisms
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TfOH-Catalyzed O-H Insertion of Carboxylic Acids with α-Aryl Diazoesters
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作者 Chen Guifang Li Hongqiang Zeng Xingrong 《有机化学》 北大核心 2025年第7期2537-2544,共8页
An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acylox... An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acyloxy esters in moderate to high yields with a broad substrate scope.All starting materials are readily available,and the reactions can be conducted in the open air at room temperature. 展开更多
关键词 carboxylic acids α-aryl diazoesters TfOH O-H insertion
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Readily Degradable and Recyclable High Molecular Weight Thiosalicylic Acid-based Copolyesters
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作者 Ge Yao Fang-Ping Ren +5 位作者 Fei Chen Lu-Ya Cao Ji Xian Xiao-Bo Pan Hong-Zhang Cao Jin-Cai Wu 《Chinese Journal of Polymer Science》 2025年第6期924-932,I0007,共10页
Most commercial plastics cannot easily degrade,which raises a number of sustainability issues.To address the current problem of plastic pollution,the research and development of easily degradable and recyclable polyme... Most commercial plastics cannot easily degrade,which raises a number of sustainability issues.To address the current problem of plastic pollution,the research and development of easily degradable and recyclable polymers has become an attractive subject.Herein,a new monomer of thiosalicylic methyl glycolide(TSMG)was synthesized using one-pot method and high molecular weight poly(thiosalicylic methyl glycolide)(PTSMG,M_(n) up to 300 kDa)can be obtained via the ring-opening polymerization(ROP)of TSMG.PTSMG exhibits good closed-loop recyclability and hydrolytic degradability,where PTSMG can generate pristine monomers through sublimation thermal depolymerization conditions due to the presence of thiophenol ester bond in the polymer chains,and can be degraded rapidly in aqueous solution,which provides a potential solution to the current plastic pollution problem. 展开更多
关键词 Hydrogen-bonding catalysts Closed-loop recycling Hydrolytic degradation Ring-opening polymerization Poly(thiophenol ester)
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Syntheses,structures,and catalytic performances of complexes with 4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid ligands
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作者 LING Weizhong LIN Jingyi +3 位作者 ZHU Jianglin LIANG Yuyi DAI Shanshan LI Yu 《无机化学学报》 北大核心 2026年第1期152-160,共9页
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(... Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3. 展开更多
关键词 COMPLEX dicarboxylic acid catalytic properties Knoevenagel reaction
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The study on citric acid-modified HUSY catalyzed alkylation of phenol with cyclohexanol
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作者 HUA Canhao WU Jingfeng +2 位作者 ZHU Lingjun XU Guangwen WANG Shurong 《燃料化学学报(中英文)》 北大核心 2026年第3期58-70,共13页
Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylat... Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylation-hydrogenation processes.This study systematically evaluates the catalytic performance of various zeolites(Hβ,HZSM-5,MCM-41 and HUSY)in the alkylation reaction of phenol with cyclohexanol.Characterization results demonstrate that HUSY zeolite showed superior catalytic activity compared to other zeolites,attributable to its favorable pore architecture and well-balanced acid site distribution that synergistically facilitate molecular diffusion and catalytic transformations.To further enhance the catalytic properties,HUSY zeolite was modified with citric acid at various concentrations and compared with those treated with NaOH and oxalic acid.The results revealed that citric acid treatment preserved the crystallinity of the zeolite while modulating its acid distribution and pore structure.All modified zeolites enhanced phenol alkylation activity.Notably,the HUSY-0.5M catalyst,which exhibited the highest medium-strong acid to total acid ratio,achieved superior catalytic performance,80.4%conversion of phenol and 99.6%selectivity for alkylation products.The catalyst also exhibited high activity in the alkylation of various lignin-derived compounds,demonstrating its broad applicability.This work provides a new strategy for the valorization of lignin-derived phenols into high-value fuel precursors through alkylation. 展开更多
关键词 citric acid modification HUSY phenolic alkylation aviation fuel
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Linoleic acid alleviates mood disorders in mice by modulating microglia differentiation and arachidonic acid metabolism
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作者 Meishan Lu Yanjun Liu +4 位作者 Mengxue He Jiachen Shi Yanan Wang Xue Li Yuanfa Liu 《Food Science and Human Wellness》 2026年第2期892-907,共16页
In previous research,we demonstrated that long-term consumption of thermally oxidized oil leads to neuroinflammation and anxiety in mice.Therefore,in this study,we employed polar lipid components from thermo-induced o... In previous research,we demonstrated that long-term consumption of thermally oxidized oil leads to neuroinflammation and anxiety in mice.Therefore,in this study,we employed polar lipid components from thermo-induced oxidized oil to induce neurodamage.Behavioral assessments revealed that both the linoleic acid and AUDA(a classical inhibitor of soluble epoxide hydrolase)groups exhibited significantly reduced anxiety-like behaviors compared to the model group(P<0.05).Immunofluorescence analysis indicated that microglial activation in the hippocampus was attenuated in both the linoleic acid and AUDA groups relative to the model group,accompanied by a reduction in the m RNA expression of pro-inflammatory cytokines(IL-1β,IL-6,NOS2,TNF-α)and an upregulation of neuroprotective factors(IL-4,IL-10,BDNF).Lipidomic profiling of hippocampal tissue revealed that the lipid composition of the linoleic acid group closely resembled that of the AUDA group,with a significant downregulation of cardiolipin(CL)compared to the control group,consistent with alterations in the membrane potential channel receptor TRPC1.Both linoleic acid and AUDA inhibited the m RNA expression of EPHX2,leading to an increase in epoxyeicosatrienoic acids(EETs)levels.Furthermore,linoleic acid upregulated the expression of cytochrome P450 enzymes(CYP2J6)and lipoxygenase(LOX2S),which further upregulated the synthesis of EETs,and increased the content of 9-HODE and 13-HODE.These findings collectively suggest that linoleic acid alleviates neuroinflammation by modulating microglial differentiation and attenuates neurodegeneration induced by thermally oxidized oil through the regulation of arachidonic acid metabolism and the linoleic acid metabolic pathway,leading to the production of neuroprotective lipid mediators.Therefore,linoleic acid may serve as a potential neuro-nutrient for the treatment of anxiety disorders.This provided a scientific basis for the development of specialized medical foods aimed at protecting neural health. 展开更多
关键词 Linoleic acid ANXIETY MICROGLIA Arachidonic acid
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Taurodeoxycholic,taurocholic,and glycocholic acids promote hepatic gluconeogenesis via TGR5 in dairy cows
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作者 Miaomiao Zhu Yining Zheng +7 位作者 Shiyang Lou Ruixu Zhang Dingping Feng Xinjian Lei Lei Chen Jianguo Wang Junhu Yao Lu Deng 《Journal of Animal Science and Biotechnology》 2026年第1期500-515,共16页
Background Ruminants and monogastric animals exhibit significant differences in gluconeogenic efficiency.In dairy cows,hepatic gluconeogenesis serves as the primary source of glucose.Metabolites modulate gluconeogenes... Background Ruminants and monogastric animals exhibit significant differences in gluconeogenic efficiency.In dairy cows,hepatic gluconeogenesis serves as the primary source of glucose.Metabolites modulate gluconeogenesis efficiency through allosteric regulation,redox state,and signal transduction pathways.However,the liver-enriched metabolites that regulate hepatic gluconeogenesis in dairy cows and their specific regulatory mechanisms remain incompletely characterized.Results Six Holstein dairy cows and six Duroc×(Landrace×Yorkshire)(DLY)crossbred pigs served as research subjects.Employing non-targeted and targeted metabolomics,we discovered that three bile acids—taurodeoxycholic acid(TDCA),taurocholic acid(TCA),and glycocholic acid(GCA)—were highly enriched in Holstein dairy cows'livers.In bovine hepatocytes,individual or combined stimulation of these bile acids significantly upregulated the expression of gluconeogenesis genes(FBP1,PCK1 and G6PC)and enhanced glucose production.In fasting mice with induced gluconeogenesis,TDCA,TCA,and GCA increased fasting blood glucose levels,and pyruvate tolerance tests further revealed their capacity to enhance hepatic gluconeogenesis,enabling more efficient glucose synthesis from pyruvate.Mechanistically,these bile acids activated Takeda G protein-coupled receptor 5(TGR5),elevated intracellular cAMP levels,and ultimately enhanced gluconeogenesis via the transcription factor cAMP-response element binding protein(CREB).Notably,a TGR5 inhibitor abrogated the stimulatory effects of TDCA,TCA,and GCA on hepatic gluconeogenesis in fasting mice.Conclusion TDCA,TCA,and GCA are key metabolites promoting hepatic gluconeogenesis in dairy cows,with TGR5 as the pivotal receptor and the cAMP/PKA/CREB pathway as the critical downstream mechanism. 展开更多
关键词 cAMP-response element binding protein GLUCONEOGENESIS Glycocholic acid Takeda G protein-coupled receptor 5 Taurocholic acid Taurodeoxycholic acid
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Contents of linoleic acid,α-linolenic acid and their ratio in human milk,influence factors,and effects on infant health
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作者 Jiahui Yu Lili Zheng +7 位作者 Shengyuan Ye Xingwang Ye Shuangshuang Chen Zhiyuan Yan Zhengdong Liu Yuanyuan Yan Wei Wei Xingguo Wang 《Food Science and Human Wellness》 2026年第1期28-37,共10页
Both linoleic acid(18:2 n-6,LA)andα-linolenic acid(18:3 n-3,ALA)are essential fatty acids for infants.The contents of LA and ALA,and their ratio exhibited significant changes in human milk over the past 4 decades,whi... Both linoleic acid(18:2 n-6,LA)andα-linolenic acid(18:3 n-3,ALA)are essential fatty acids for infants.The contents of LA and ALA,and their ratio exhibited significant changes in human milk over the past 4 decades,which were not well summarized.Here,we summarized these values in 9898 human breast milk samples of 6664 mothers from 50 countries in 81 studies.A literature search was conducted using PubMed,Embase,and Web of Science between January 1980 and October 2023.The 95%confidence interval of LA/ALA ratio across lactation and gestation ranged from 14.24 to 31.26.The LA content was higher in China and Turkey(>20%)whereas the ALA content was below 1%in Africa.The LA/ALA ratio in countries along the Mediterranean coast exceeded 20 or even 30.LA and ALA contents increased significantly(P<0.01)while the ratio remained stable over the last 40 years.Multivariate meta-regression results showed that regions significantly(P<0.01)determined the LA,ALA,and LA/ALA ratio.Especially,maternal diet could definitely explain the variation while the effects of gestational age,lactation period was not significant.Clinical trials demonstrated that decreasing the LA/ALA ratio increased docosahexaenoic acid(22:6 n-3,DHA)status,reduced arachidonic acid(20:4 n-6,AA)contents,exerted no effect on the visual function of infants,and reached no consensus on growth.The current review aims to provide an overview on the LA and ALA contents and their ratio in human breast milk to raise concern in infant formula. 展开更多
关键词 Human milk Linoleic acid α-Linolenic acid Essential fatty acid Infant nutrition Clinical trial Lactation period Maternal diet
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Lysophosphatidic acid signaling:Transmembrane modulators in the central nervous system
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作者 Alexandra Polyzou Alexandros Κ.Tsiouris +2 位作者 Charalampos Labrakakis Britta J.Eickholt George Leondaritis 《Neural Regeneration Research》 2026年第3期1104-1105,共2页
Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,includi... Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018). 展开更多
关键词 transmembrane modulators cerebrospinal fluidvaries variety lipid species lysophosphatidic acid biological fluidsincluding lysophosphatidic acid lpa saturated unsaturated fatty acids pleiotropic lipid agonist
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Efficient continuous synthesis of 2-[3-(trifluoromethyl)phenyl]malonic acid,a key intermediate of Triflumezopyrim,coupling with esterification-condensation-hydrolysis
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作者 Yuexiang Liu Xiangqiao Yang +6 位作者 Tong Lin Guantian Yang Xiaoyong Xu Bubing Zeng Zhong Li Weiping Zhu Xuhong Qian 《Chinese Chemical Letters》 2025年第1期234-238,共5页
Triflumezopyrim(TFM)is a novel mesoionic pyrido[1,2-α]pyrimidinones insecticide,which acts on nicotinic acetylcholine receptors(n ACh Rs)and has no cross-resistance with other insecticides.Herein,we firstly developed... Triflumezopyrim(TFM)is a novel mesoionic pyrido[1,2-α]pyrimidinones insecticide,which acts on nicotinic acetylcholine receptors(n ACh Rs)and has no cross-resistance with other insecticides.Herein,we firstly developed a new continuous flow approach to synthesis 2-[3-(trifluoromethyl)phenyl]malonic acid,a key intermate of TFM,coupling with esterification,condensation,and hydrolysis.All three-step reactions were optimized and transformed into a continuous synthesis mode by three micro reaction units.Compared with the batch mode,the total reaction time and overall separation yield were improved from more than 12 h and 60%to 18 min and 73.38%,respectively.The solvent consumption and waste emission were significantly reduced,which also provides an eco-friendly and efficient potential tool for the development and production of mesoionic pyrido[1,2-α]pyrimidinones insecticide. 展开更多
关键词 Triflumezopyrim(TFM) 2-[3-(Trifluoromethyl)phenyl]malonic acid Continuous flow synthesis MICRO-REACTOR
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Structure insight into FtsZ function maintaining under acid stress of Streptococcus mutans
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作者 Yuxing Chen Yongliang Li +9 位作者 Jiahao Niu Liuchang Yang Yaqi Chi Xue Cai Fengjiao Xin Jie Zhang Xianyang Fang Yiqin Gao Manas Mondal Xiaoyan Wang 《International Journal of Oral Science》 2026年第1期90-102,共13页
Understanding the acid resistance mechanism of S.mutans is crucial for preventing dental caries.FtsZ is the core protein for cell division in bacteria that can polymerize into Z-rings and drive cytokinesis.Our previou... Understanding the acid resistance mechanism of S.mutans is crucial for preventing dental caries.FtsZ is the core protein for cell division in bacteria that can polymerize into Z-rings and drive cytokinesis.Our previous study revealed that the FtsZ in S.mutans(SmFtsZ) has higher self-assembly and GTPase activity under acidic stress,which may be responsible for acid resistance and ca riogenesis of S.mutans.However,the functional structure mechanism of SmFtsZ under low pH conditions is still unclear.Here,we further reported the crystal structure of S.mutans FtsZ,revealing a unique lateral interface.Through protein polymerization and GTPase activity assay,we experimentally demonstrated that the mutation of Arg68 on this lateral interface significantly reduced the functional activity of FtsZ in an acidic environment.The phenotype assay and rat caries model further showed that the mutation of Arg68 effectively inhibited the acid resistance of S.mutans and the occurrence and progress of dental caries in vivo.By employing a molecular dynamics simulation analysis,we conclude that the mutation of Arg68 disrupts the conformation change necessary for SmFtsZ polymerization under acidic conditions.Our study proposes a novel mechanism to maintain FtsZ function in bacteria and could be a potential target for antimicrobial drugs to inhibit the growth of S.mutans in acidic environments. 展开更多
关键词 ca riogenesis FTSZ acid resistance dental cariesftsz acidic stress cell division functional structure mechanism low ph conditions
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Phytic acid-assisted amorphization of bone mineral for improved phosphorus fertilizer efficiency
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作者 Mengli Guo Jiyao Zhou +4 位作者 Ailing Li Fei Xia Lei Shi Richard A.Martin Dong Qiu 《Advanced Agrochem》 2026年第1期58-64,共7页
Phosphorus plays an indispensable role in the food chain,yet phosphorus mineral resources are finite,underscoring the urgency for developing a closed-loop phosphorus economy.Although there have been advances in phosph... Phosphorus plays an indispensable role in the food chain,yet phosphorus mineral resources are finite,underscoring the urgency for developing a closed-loop phosphorus economy.Although there have been advances in phosphorus recovery from various waste materials,modern agriculture still depends on adequate phosphorus supply to support plant growth.In this study,we explored the amorphization of Ox bone using phytic acid(OxPA),and investigated how varying treatment durations influence the resulting structure.Inductively Coupled Plasma(ICP)analysis was employed to quantify phosphate solubilization.Additionally,pot experiments were conducted to assess the phosphate efficiency of Ox-PA in comparison to untreated Ox bone and control group.The results showed that Ox-PA exhibited significantly higher phosphate solubilization(2973 ppm)than untreated counterpart(13 ppm).When used as a fertilizer,Ox-PA markedly enhanced both aboveground and belowground biomass and root development in maize plants.Moreover,it facilitated increased phosphorus uptake by the plants during their early growth stages.These findings indicate that Ox-PA not only holds significant potential for promoting agronomic sustainability but also contributes meaningfully to the establishment of a circular phosphorus economy. 展开更多
关键词 Amorphization Ox bone Phytic acid PHOSPHATE SOLUBILIZATION
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Taurochenodeoxycholic acid promotes abdominal fat deposition by modulating the crosstalk between bile acid metabolism and intestinal microbiota in broilers
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作者 Xi Sun Chaohui Wang +4 位作者 Xiaoying Liu Yun Li Zhouzheng Ren Xiaojun Yang Yanli Liu 《Journal of Animal Science and Biotechnology》 2026年第1期531-545,共15页
Background The role of bile acids in modulating the gut microbiota and their impact on host metabolism has garnered significant attention.Taurochenodeoxycholic acid(TCDCA)is the predominant bile acid within the chicke... Background The role of bile acids in modulating the gut microbiota and their impact on host metabolism has garnered significant attention.Taurochenodeoxycholic acid(TCDCA)is the predominant bile acid within the chicken bile acid pool and is closely related to metabolic disorders.The current study aims to investigate the potential effects of TCDCA on abdominal fat deposition in broilers.From 14 to 28 days of age,the broilers in the CON group received an oral administration of 1 mL of saline,while those in the treatment groups were administered 1 mL of a solution containing 0.05 g,0.10 g,or 0.20 g of TCDCA.Results The results showed that TCDCA treatments from 14 to 28 d had no significant effects on BW,ADFI,ADG and FCR in broilers at the age of 28 days of age.However,the abdominal fat percentage in the 0.20 g TCDCA group significantly increased,accompanied by higher TBA and HDL-c levels,as well as a reduction in apolipoprotein B levels in serum.In addition,serum triglyceride levels tended to be higher in the 0.20 g TCDCA group(P=0.098).The 0.20 g TCDCA treatment increased the gene expressions of SREBP-1,C/EBP-α,and ELOVL6,while decreasing the mRNA abundance of ATGL and CPT-1 in the abdominal fat.Serum levels of TCDCA,TDCA,and THDCA were significantly higher after 0.20 g TCDCA administration,while TCA levels were significantly lower,as determined by the targeted bile acid metabolomics analysis.Conversely,hepatic mRNA levels of CYP7A1,CYP27A1,BAAT,and BSEP were increased in the 0.20 g TCDCA group.The oral administration of 0.20 g TCDCA also upregulated the expression of FXR,VDR,and FGF19 in abdominal fat.The 16S rRNA analysis of cecal microbiota revealed that a decrease in the Shannon and Simpson indexes in the 0.20 g TCDCA group,and an increase in the Firmicutes/Bacteroidetes ratio.LEfSe analysis revealed that the predominant bacteria in the CON group were Streptococcus and Oscillospira at the genus level,while Lactobacillus,Parabacteroides,Anaeroplasma,and Helicobacter were identified as the dominant genera in the 0.20 g TCDCA group.Functional predictions for the gut microbiota exhibited that lipid metabolism,replication and repair pathway were enhanced in the 0.20 g TCDCA group.Correlation analysis demonstrated that the abundance of Lactobacillus was positively correlated with serum levels of TCDCA,THDCA,and TDCA,while the abundance of Streptococcus and Oscillospira showed a positive correlation with serum TCA levels.Conclusion Overall,this study elucidates that the intervention of 0.20 g TCDCA may promote abdominal fat deposition by activating bile acid receptors in abdominal fat,and concurrent alterations in both the intestinal microbial community and bile acid profile. 展开更多
关键词 Abdominal fat BROILER Cecal microbiota Taurochenodeoxycholic acid
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Elaidic acid-induced inhibition of mitophagy activated renal tubular cell necroptosis via ROS/RIPK3/MLKL pathway
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作者 Shuang Guan Zelin Yu +3 位作者 Shengzhuo Zhang Xiujuan Bu Xuming Deng Jing Lu 《Food Science and Human Wellness》 2026年第2期789-803,共15页
Elaidic acid(EA)is a typical trans fatty acid(TFA)that emerges during the processing of various fatty foods.In this study,we found that EA induced renal injury with necroptosis.Pretreatment with a reactive oxygen spec... Elaidic acid(EA)is a typical trans fatty acid(TFA)that emerges during the processing of various fatty foods.In this study,we found that EA induced renal injury with necroptosis.Pretreatment with a reactive oxygen species(ROS)inhibitor and a RIPK3 inhibitor alleviated EA-induced necroptosis.The data indicated that EA induced renal necroptosis through ROS/RIPK3/MLKL pathway.In mechanistic studies,we explored how EA induced ROS production.Results indicated that EA caused mitochondrial damage by testing MMP,MFN1,VDAC,and FIS1.Further,EA suppressed mitophagy by testing the levels of LC3,p62,PINK1,Parkin,colocalization of LC3 and Mito-Tracker Red.Mitophagy is a process of selective degradation of damaged mitochondria.A large number of damaged mitochondria couldn't be cleared by mitophagy in time,which increased ROS levels in renal cells.Pretreatment with a mitophagy activator decreased EA-induced ROS levels and mitochondrial damage.Taken together,our data identified that EA induced renal necroptosis by destroying mitochondria and inhibiting mitophagy,thereby activating the ROS/RIPK3/MLKL pathway. 展开更多
关键词 Elaidic acid RENAL NECROPTOSIS MITOPHAGY Reactive oxygen species
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Palmitic acid-induced autolysosomal dysfunction and lipotoxicity in neuroinflammation and neurodegeneration
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作者 Eka Norfaishanty Saipuljumri Jialiu Zeng Chih Hung Lo 《Neural Regeneration Research》 2026年第7期2806-2811,共6页
Neurodegenerative disorde rs such as Alzheimer's and Parkinson s diseases are increasingly associated with metabolic dysfunction,including obesity,type 2 diabetes,and metabolic dysfunction-associated steatotic liv... Neurodegenerative disorde rs such as Alzheimer's and Parkinson s diseases are increasingly associated with metabolic dysfunction,including obesity,type 2 diabetes,and metabolic dysfunction-associated steatotic liver disease.Central to this connection is the dysregulation of lipid metabolism,which extends beyond peripheral tissues to the brain,defective autolysosomal function,oxidative stress,inflammation,and insulin resistance.Lipids,which constitute over half of dry weight of the brain,play critical roles in ene rgy provisio n,structural integrity,and synaptic function.Dys regulation of lipid metabolism contributes to neuroinflammation,impaired neuronal function,and disrupted blood-brain barrier integrity.Palmitic acid,a saturated fatty acid abundant in high-fat diets,serves as a key model for studying lipid-induced toxicity(lipotoxicity)in the brain.Palmitic acid disrupts autophagy and lysosomal function,mitochondrial function,trigge ring oxidative stress,contributing to neuroinflammation and neurodegeneration.These effects are particularly pronounced in neurons,which are highly susceptible to lipid-induced toxicity due to their high metabolic demands.Glial cells,including astrocytes,microglia,and oligodendrocytes,also exhibit distinct vulnerabilities and adaptive responses to lipid metabolism dysregulation,further contributing to neuroinflammation and demyelination.Therapeutic strategies,such as supplementation with polyunsaturated fatty acids,AMP-activated protein kinase activation,and lysosome-ta rgeted interventions,show promise in mitigating palmitic acid-induced lipotoxicity and restoring cellular homeostasis.This review comprehensively examines palmitic acid-induced lipotoxicity and its impact on autolysosomal dysfunction across various central nervous system cell types,including neurons,astrocytes,microglia,and oligodendrocytes.Additionally,it highlights therapeutic approaches to restore autolysosomal function under lipotoxic conditions.Advances in multi-omics technologies and a deeper unde rstanding of intercellular crosstalk offer new avenues for develo ping targeted the rapies to resto re autolysosomal function,and attenuate neuroinflammation and neurodegeneration. 展开更多
关键词 autolysosomal dysfunction LIPOTOXICITY metabolic dysfunction NEUROINFLAMMATION palmitic acid
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Saturated Alcohols Electrocatalytic Oxidations on Ni-Co Bimetal Oxide Featuring Balanced B-and L-Acidic Active Sites
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作者 Junqing Ma Wenshu Luo +9 位作者 Xunlu Wang Xu Yu Jiacheng Jayden Wang Huashuai Hu Hanxiao Du Jianrong Zeng Wei Chen Minghui Yang Jiacheng Wang Xiangzhi Cui 《Nano-Micro Letters》 2026年第2期105-123,共19页
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro... Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts. 展开更多
关键词 Solid-acid electrocatalyst Alcohol oxidation reaction Bronsted acid sites Lewis acid sites C_(1)-C_(6)saturated alcohols
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Unbalanced lipid metabolism in anther,especially the disorder of the alpha-linolenic acid metabolism pathway,leads to cotton male sterility
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作者 Lihong Ma Pengtao Wang +7 位作者 Qian-Hao Zhu Xinqi Cheng Tao Zhang Xinyu Zhang Huaguo Zhu Zuoren Yang Jie Sun Feng Liu 《Journal of Integrative Agriculture》 2026年第2期610-623,共14页
Recent studies have shown that lipid metabolism is a key factor affecting anther development and male fertility.However,how plants regulating the metabolic balance of multiple lipids to ensure proper anther developmen... Recent studies have shown that lipid metabolism is a key factor affecting anther development and male fertility.However,how plants regulating the metabolic balance of multiple lipids to ensure proper anther development and male fertility remains unclear.Analyzing lipid molecules related to anther fertility and genes responsible for their biosynthesis is crucial for understanding the physiological significance of lipid metabolism in crop fertility.In this study,we compared the transcriptome and the composition and content of lipids in anthers of two upland cotton(Gossypium hirsutum) materials,Shida 98(WT) and its nearly-isogenic male sterile line Shida 98A(MS).Transcriptomics analysis identified many differentially expressed genes(DEGs) between the two materials,with the genes of the alpha-linolenic acid metabolism pathway being the most significantly associated with the male sterility phenotype.Investigations on lipids revealed that the MS anthers over-accumulated free fatty acids(FFAs),phosphatidic acid(PA),mono-and di-galactosyldiacylglycerol(MGDG and DGDG),and had a decreased content of triacylglycerol(TAG),which was closely related to the abnormal metabolism of alpha-linolenic acid(C18:3);therefore,the major lipids containing C18:3-acyl chains,such as PA,MGDG,DGDG,and TAG,are proposed to play a major role in cotton anther development.We also showed that an excessive level of MGDG and DGDG caused jasmonic acid(JA) overaccumulation in MS anthers,which in turn inhibited the expression of GhFAD3 and consequently reduced the C18:3 content,presumably via a feedback regulation mechanism,ultimately affecting plant fertility.Together,our results revealed the importance of a balanced lipid metabolism in regulating the development of cotton anther and pollen and consequently male fertility. 展开更多
关键词 COTTON ANTHER male sterility lipid metabolism alpha-linolenic acid
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