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杨树桑黄化学成分研究
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作者 任航洁 陶玉佳 +3 位作者 李刚 李华强 秦路平 施琦 《中草药》 北大核心 2026年第3期799-805,共7页
目的研究杨树桑黄Sanghuangporus vaninii的化学成分及其对肿瘤坏死因子(tumor necrosis factor-α,TNF-α)诱导人类风湿性关节炎成纤维细胞MH7A的活性。方法运用多种分离技术,包括硅胶柱色谱、ODS柱色谱及半制备高效液相色谱等,进行分... 目的研究杨树桑黄Sanghuangporus vaninii的化学成分及其对肿瘤坏死因子(tumor necrosis factor-α,TNF-α)诱导人类风湿性关节炎成纤维细胞MH7A的活性。方法运用多种分离技术,包括硅胶柱色谱、ODS柱色谱及半制备高效液相色谱等,进行分离纯化;采用UV、IR、HRESIMS、NMR、碳谱计算和ECD等波谱技术鉴定化合物结构;采用CCK-8法评价倍半萜化合物抑制肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)诱导的MH7A细胞增殖的活性,以及ELISA法检测炎症因子白细胞介素-6(interleukin-6,IL-6)和白细胞介素-1β(interleukin-1β,IL-1β)水平。结果从杨树桑黄95%乙醇提取物中分离得到9个化合物,分别鉴定为(4S,5S,6R)-2-甲基-5,6-二羟基-[R-6-(4-羟甲基)-3-环己烯]-呋喃-2(5H)-酮(1)、phellilane D(2)、phellilane C(3)、(+)-γ-ionylideneacetic acid(4)、elgonene A(5)、3E-4-(3,4-二羟苯基)-3-丁烯-2-酮(6)、3,4-二羟基苯甲酸乙酯(7)、E-4-对羟基苯基-3-丁烯-2-酮(8)和原儿茶醛(9)。化合物1、3和4在20μmol/L浓度内均能显著抑制TNF-α诱导的MH7A细胞增殖,在20μmol/L时其抑制率分别为(38.9±1.32)%、(46.21±0.86)%和(36.59±1.51)%;化合物1、3和4均能显著降低TNF-α诱导后的MH7A细胞IL-6和IL-1β的生成量。结论化合物1~5为没药烷型倍半萜化合物,6~9为苯酚类化合物,其中化合物1为新的倍半萜化合物,命名为杨树桑黄萜素Q;化合物7为首次从杨树桑黄中分离得到。化合物1、3和4均能显著抑制TNF-α诱导的MH7A细胞增殖并具有抗炎活性。 展开更多
关键词 桑黄 倍半萜 苯酚类化合物 抗类风湿关节炎 杨树桑黄萜素Q phellilane C (+)-γ-ionylideneacetic acid
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Human serum albumin modified in myeloperoxidasedependent reactions is a mediator of neutrophil extracellular trap formation 被引量:1
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作者 Daria V.Grigorieva Nikolay P.Gorbunov +7 位作者 Valeria A.Kostevich Alexey V.Sokolov Liliya Yu.Basyreva Ekaterina V.Shmeleva Tatyana V.Vakhrusheva Sergey A.Gusev Irina V.Gorudko Oleg M.Panasenko 《Journal of Biomedical Research》 2026年第2期147-158,共12页
Activation of neutrophil membrane receptors initiates intracellular signal transduction cascades that orchestrate the cell's effector functions,including phagocytosis,production of reactive oxygen and halogen spec... Activation of neutrophil membrane receptors initiates intracellular signal transduction cascades that orchestrate the cell's effector functions,including phagocytosis,production of reactive oxygen and halogen species,degranulation,and NETosis(formation of neutrophil extracellular traps[NETs]).NETs,which contain antimicrobial compounds such as myeloperoxidase(MPO),represent a strategy to combat infection.However,excessive production of NETs promotes thrombosis,diabetes mellitus,and other diseases.Therefore,investigations into the mechanisms of NETosis and the identification of modulators of this process are critical for developing strategies to address NETosis-related disorders.Here,we identified a novel NETosis inducer,human serum albumin(HSA)modified by the MPO product hypochlorous acid(HSAHOCl),whose accumulation in vivo was correlated with inflammatory processes.Using human blood neutrophils,we investigated HSAHOCl-induced NETosis and detected NET formation by flow cytometry.The results showed that the mechanism of HSAHOClinduced NETosis involved MPO,NADPH oxidase,and phosphatidylinositol 3-kinases(PI3Ks),and that HSAHOCl activated a reactive oxygen species-dependent suicidal type of NETosis.Moreover,HSAHOCl-induced NETosis was inhibited by an anti-HSAHOCl monoclonal antibody.Thus,our findings may facilitate the development of strategies to modulate NETosis in inflammation associated with elevated MPO activity. 展开更多
关键词 NETosis neutrophil extracellular traps human serum albumin MYELOPEROXIDASE hypochlorous acid reactive halogen species
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Description and Evaluation of the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)Model Version 1.0 被引量:1
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作者 EPICC Model Working Group 《Advances in Atmospheric Sciences》 2026年第4期671-694,I0001-I0006,共30页
We present a comprehensive description and benchmark evaluation of the global–regional chemical transport model called the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)model.The framework... We present a comprehensive description and benchmark evaluation of the global–regional chemical transport model called the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)model.The framework incorporates(1)grid configuration,(2)transport dynamics,(3)chemical mechanisms,(4)aerosol processes,(5)wet/dry deposition parameterizations,and(6)heterogeneous chemistry treatments associated with sulfate,nitrous acid(HONO)chemistry,and aerosol/cloud–photolysis interactions(APIs/CPIs).Openly shared with the atmospheric research community,the model facilitates integration of advanced physicochemical schemes to enhance simulation accuracy.Globally,the model demonstrates realistic representations of ozone(O_(3))and aerosol optical depth.The EPICC model generally demonstrates robust performance in simulating regional concentrations of O_(3) and PM_(2.5)(and its components)in China.It successfully captures vertical profiles of both global and regional O_(3).Notably,the model mitigates frequently reported sulfate underestimations in highly industrialized regions of China.The model accurately captures two regional severe pollution episodes observed in eastern China(January/June 2021).Sensitivity experiments highlight the critical roles of heterogeneous chemical mechanisms associated with sulfate,HONO chemistry,APIs,and CPIs in capturing PM_(2.5) and O_(3) concentrations in China.Improved sulfate mechanisms result in an increase of approximately 32.4%(2.8μg m^(−3))in simulated winter sulfate concentrations when observations exceed 10μg m^(−3).Enhanced HONO elevates winter O_(3) and PM_(2.5) by≤20 and≤10μg m^(−3),respectively.Overall,CPIs dominate over APIs in improving O_(3) and PM_(2.5) simulations across China.Locally,APIs mitigate PM_(2.5) and O_(3) discrepancies in the Sichuan Basin.Seasonal cloud–chemistry coupling explains the weaker impact of PM_(2.5) in summer. 展开更多
关键词 EPICC model PM_(2.5) O_(3) sulfate nitrous acid aerosol/cloud-photolysis interactions
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PcUGT84A82 catalyzes a key step in the biosynthesis of galloylated macrocyclic polyphenols in Penthorum chinense Pursh 被引量:1
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作者 Yajing Li Yiru Liu +11 位作者 Xiao Li Ke Zhang Yun Wang Minghui Lu Xu Yang Yinan Zou Jiajia Cao Lianna Sun Junfeng Chen Doudou Huang Wansheng Chen Ying Xiao 《The Crop Journal》 2026年第1期247-254,共8页
Penthorum chinense Pursh has been used for centuries as an herbal medicine and food in East Asia.The main active substances in P.chinense are galloylated macrocyclic polyphenolic compounds,which have excellent medicin... Penthorum chinense Pursh has been used for centuries as an herbal medicine and food in East Asia.The main active substances in P.chinense are galloylated macrocyclic polyphenolic compounds,which have excellent medicinal properties.Galloylation and glycosylation are key steps in the formation of polyphenolic compounds,as the glycosylation of flavonoids is required for the acylation of flavonoid glycosides,and the glycosylation of gallic acid is necessary for its role as an acyl donor.Therefore,glycosylation to generate the acyl donor or acceptor is a core step in the biosynthesis of polyphenolic compounds.However,how this glycosylation occurs in P.chinense is unknown.In this study,we determined that the UDP-glucose transferase PcUGT84A82 mediates the glycosylation of gallic acid and pinocembrin to produce 1-O-Galloyl-β-D-glucose and pinocembroside,respectively.Metabolic profiling of polyphenolic compounds using UHPLC-ESI–Q-TOF/MS revealed high levels of polyphenols in flowers,leaves,and roots,and low levels in stems of P.chinense.We performed isoform-sequencing(Iso-seq)to assemble a full-length transcriptome of P.chinense,from which we identified 58 UGT family members.PcUGT84A82 is highly similar to functional UGTs in other plant species,and PcUGT84A82 transcript levels were positively correlated with the levels of various polyphenolic compounds.We validated the function of PcUGT84A82 via in vitro enzyme assays and transient expression in Nicotiana benthamiana leaves.Subcellular localization tests showed that PcUGT84A82 localizes to the nucleus and cytoplasm.In summary,PcUGT84A82 catalyzes the conversion of gallic acid to 1-O-Galloyl-β-D-glucose as the acyl donor and pinocembrin to pinocembroside as the acyl acceptor,mediating the biosynthesis of galloylated macrocyclic polyphenolic compounds in P.chinense.These findings lay the foundation for elucidating the entire biosynthetic pathway of active polyphenols in this important herbal plant species. 展开更多
关键词 POLYPHENOL Penthorum chinense Pursh UGT84A82 1-O-Galloyl-β-D-glucose Gallic acid
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Short-chain fatty acids mediate enteric and central nervous system homeostasis in Parkinson’s disease:Innovative therapies and their translation 被引量:1
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作者 Shimin Pang Zhili Ren +1 位作者 Hui Ding Piu Chan 《Neural Regeneration Research》 2026年第3期938-956,共19页
Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’... Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease. 展开更多
关键词 ALPHA-SYNUCLEIN blood-brain barrier blood circulation central nervous system ENDOCRINE enteric nervous system glial cell gut-brain axis gut microbiota intestinal barrier neuron Parkinson’s disease short chain fatty acids vagus nerve
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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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Syntheses,crystal structures,catalytic and anti-wear properties of zinc(Ⅱ),nickel(Ⅱ)and cadmium(Ⅱ)complexes constructed from a terphenyl-tricarboxylate ligand
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作者 ZHAO Zhenghua LIU Yufeng +2 位作者 ZHANG Qing SHI Zifa GU Jinzhong 《无机化学学报》 北大核心 2026年第1期170-180,共11页
Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been construc... Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3. 展开更多
关键词 COMPLEXES tricarboxylic acid catalytic properties Knoevenagel condensation reaction anti-wear performance
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Influence of the distance between Brønsted acid sites and Mo sites in Mo/HZSM-5 on the mechanism of methane dehydroaromatization performance
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作者 WANG Ce WEI Lihong +2 位作者 ZHANG Qinghao ZHANG Hongxiang SUN Yuewen 《燃料化学学报(中英文)》 北大核心 2026年第4期68-81,共14页
Methane dehydroaromatization(MDA)presents a promising carbon-neutral pathway for benzene,toluene,and xylene(BTX)production,alternative to petroleumderived routes.Elucidating the regulatory mechanisms of Brønsted ... Methane dehydroaromatization(MDA)presents a promising carbon-neutral pathway for benzene,toluene,and xylene(BTX)production,alternative to petroleumderived routes.Elucidating the regulatory mechanisms of Brønsted acid site(BAS)strength on reaction pathways,alongside the spatial proximity effects between BAS and Mo active sites in bifunctional synergy,remains a critical scientific challenge in catalyst design.This study systematically tunes both BAS strength(via isomorphous metal substitution)and Mo-BAS spatial proximity in zeolites,integrating MDA catalytic evaluations with density functional theory(DFT)calculations to dissect their individual contributions.Strongly acidic BAS catalysts(compared to moderately acidic Fe/Ga-substituted counterparts)exhibit superior performance,evidenced by enhanced aromatic yields.Conversely,weakly acidic Bsubstituted zeolites demonstrate optimal mono-/bifunctional synergy,outperforming moderate-acid systems.DFT results reveal that acid strength dictates C−H activation mechanisms by modulating the energy barriers of rate-determining steps.While Al-zeolites deliver the highest activity,B-substituted systems display unique potential for mechanistic investigations.Spatial proximity analysis indicates that micrometer-scale Mo-BAS distances hinder effective synergy due to exceeding electron interaction and mass transfer limits,whereas nanometer-scale proximity enhances activity(via accelerated intermediate transport)and suppresses coke formation.These findings establish a theoretical framework for rationalizing zeolite catalyst optimization through BAS property engineering and spatial control of Mo-BAS cooperation,providing actionable guidelines for designing next-generation MDA catalysts. 展开更多
关键词 methane dehydroaromatization Brønsted acid catalytic mechanism ZEOLITE
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Integrated Transcriptomic and Metabolomic Analysis Reveals the Adaptive Mechanism of Penicillium digitatum under Modified Atmosphere Packaging Based on Amino Acid Metabolism
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作者 HAO Shanshan WANG Zhengli +3 位作者 XU Huihui JI Nana GUO Yanyin Abbas AQLEEM 《食品科学》 北大核心 2026年第6期129-144,共16页
This study employed integrated multi-omics approaches to elucidate,from the perspective of amino acid metabolism,the adaptive mechanism of Penicillium digitatum under modified atmosphere packaging(MAP)conditions.Compa... This study employed integrated multi-omics approaches to elucidate,from the perspective of amino acid metabolism,the adaptive mechanism of Penicillium digitatum under modified atmosphere packaging(MAP)conditions.Comparative analysis of natural air(Air),controlled atmosphere(CA),and MAP treatments revealed that MAP upregulated the expression of the hercynylcysteine S-oxide synthase(HCSOS),aldehyde dehydrogenase(ALDH),and monoamine oxidase(MAO)genes,thereby enhancing histidine-derived ergothioneine and methionine levels,and subsequently boosting glutathione-mediated redox homeostasis.Meanwhile,MAP induced the expression of the dihydroxyacid dehydratase(DHAD),saccharopine dehydrogenase(SDH),and arginosuccinate lyase(ASL)genes,redirecting valine,lysine,and arginine into the tricarboxylic acid(TCA)cycle to fuel ATP production.MAP also enhanced ASL-mediated arginine degradation and urea cycle activity,reducing arginine accumulation when compared to CA treatment.In contrast,while MAP induced upregulated expression of the pyrroline-5-carboxylate dehydrogenase(P5CDH)and D-amino acid oxidase(DAAO)genes,CA treatment promoted proline accumulation,reflecting stress-specific metabolic flexibility.Collectively,these findings demonstrate that MAP triggers transcriptional reprogramming of amino acid metabolism to coordinate oxidative defense,energy generation,and osmotic balance.By modulating these metabolic pathways and regulatory genes under MAP conditions,fungal adaptability can be disrupted.Hence,this study provides a promising strategy for suppressing green mold development,extending the postharvest shelf life,and improving the quality of fruits and vegetables. 展开更多
关键词 amino acid metabolism multi-omics Penicillium digitatum modified atmosphere packaging postharvest pathology
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Photocatalytic Radical-Mediated Synthesis of Unnaturalα-Amino Acids from Heteroaryl Aldehydes
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作者 Ren Ke Zhang Guanglu +3 位作者 Niu Yifan Wang Xiaomeng Chen Canyu Jiang Min 《有机化学》 北大核心 2026年第1期215-224,共10页
Non-naturalα-amino acids(α-AAs)are pivotal in drug and catalysis,yet their synthesis remains challenges.A photocatalytic strategy for the direct construction of N-heteroaryl-containingα-AAs from heteroaryl aldehyde... Non-naturalα-amino acids(α-AAs)are pivotal in drug and catalysis,yet their synthesis remains challenges.A photocatalytic strategy for the direct construction of N-heteroaryl-containingα-AAs from heteroaryl aldehydes via acyl radical intermediates is reported.This method exhibits exceptional functional group tolerance and enables late-stage diversification of peptides and carbonyl-group derivatization.Mechanistic studies confirm a radical-based pathway,while applications in peptide modification highlight its utility in bioorganic chemistry. 展开更多
关键词 PHOTOCATALYTIC non-natural amino acids heteroaryl aldehydes acyl radical electron paramagnetic resonance
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Efficient leaching and separation of iron,aluminum,and calcium from carbon-rich components in coal gasification fine slag using organic acids
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作者 NAN Tianhao ZHOU Anning +4 位作者 HAN Rui HAN Chunmeng CHEN Heng ZHANG Ningning LI Bingying 《燃料化学学报(中英文)》 北大核心 2026年第4期1-16,共16页
The efficient extraction and separation of valuable metal elements from coal gasification fine slag(CGFS)are crucial for the comprehensive high-value utilization of its constituents.This study focused on the carbon-ri... The efficient extraction and separation of valuable metal elements from coal gasification fine slag(CGFS)are crucial for the comprehensive high-value utilization of its constituents.This study focused on the carbon-rich components of CGFS(CGFS-H)and systematically investigates the selective leaching behavior of Fe^(3+),Al^(3+)and Ca^(2+)using three organic acid extractants,i.e.,citric acid,tartaric acid,and tetrasodium iminodisuccinate.Additionally,the stepwise leaching of iron,aluminum and calcium from CGFS-H is explored.The selective dissolution mechanisms of these metals by different organic acids are elucidated through X-ray diffraction(XRD),X-ray fluorescence(XRF),and scanning electron microscopy(SEM)analyses.The results indicate that tetrasodium iminodisuccinate exhibits the highest leaching selectivity for Fe^(3+),while tartaric acid demonstrateds a comparable affinity for both Fe^(3+)and Al^(3+).In contrast citric acid shows superior selectivity toward Ca^(2+).The leaching yield of Fe^(3+),Al^(3+)and Ca^(2+)after sequential leaching with the three organic acids were 79.8%,65.08%and 78.6%,respectively.These findings confirm that effective and selective separation of Fe^(3+),Al^(3+)and Ca^(2+)from CGFS-H can be achieved via optimized organic acid-based leaching strategies.This advancement provides a critical foundation for developing Ca/Fe/Al hydrotalcite materials using CGFS-H as a sustainable feedstock,thereby facilitating the transformation of waste residue into high-value functional materials and promoting resourceefficient utilization of coal gasification fine slag. 展开更多
关键词 coal gasification fine slag carbon-rich components organic acids LEACHING stepwise extraction
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Ligand-directed construction of cobalt-oxo cluster-based organic frameworks:Structural modulation,semiconductor,and antiferromagnetic properties
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作者 SHI Jinlian LIU Xiaoru XU Zhongxuan 《无机化学学报》 北大核心 2026年第1期45-54,共10页
Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully construct... Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully constructed by coordinatively assembling the semi-rigid multidentate ligand 5-(1-carboxyethoxy)isophthalic acid(H₃CIA)with the Nheterocyclic ligands 1,4-di(4H-1,2,4-triazol-4-yl)benzene(1,4-dtb)and 1,4-di(1H-imidazol-1-yl)benzene(1,4-dib),respectively,around Co^(2+)ions.Single-crystal X-ray diffraction analysis revealed that in both complexes HU23 and HU24,the CIA^(3-)anions adopt aκ^(7)-coordination mode,bridging six Co^(2+)ions via their five carboxylate oxygen atoms and one ether oxygen atom.This linkage forms tetranuclear[Co4(μ3-OH)2]^(6+)units.These Co-oxo cluster units were interconnected by CIA^(3-)anions to assemble into 2D kgd-type structures featuring a 3,6-connected topology.The 2D layers were further connected by 1,4-dtb and 1,4-dib,resulting in 3D pillar-layered frameworks for HU23 and HU24.Notably,despite the similar configurations of 1,4-dtb and 1,4-dib,differences in their coordination spatial orientations lead to topological divergence in the 3D frameworks of HU23 and HU24.Topological analysis indicates that the frameworks of HU23 and HU24 can be simplified into a 3,10-connected net(point symbol:(4^(10).6^(3).8^(2))(4^(3))_(2))and a 3,8-connected tfz-d net(point symbol:(4^(3))_(2)((4^(6).6^(18).8^(4)))),respectively.This structural differentiation confirms the precise regulatory role of ligands on the topology of metal-organic frameworks.Moreover,the ultraviolet-visible absorption spectra confirmed that HU23 and HU24 have strong absorption capabilities for ultraviolet and visible light.According to the Kubelka-Munk method,their bandwidths were 2.15 and 2.08 eV,respectively,which are consistent with those of typical semiconductor materials.Variable-temperature magnetic susceptibility measurements(2-300 K)revealed significant antiferromagnetic coupling in both complexes,with their effective magnetic moments decreasing markedly as the temperature lowered.CCDC:2457554,HU23;2457553,HU24. 展开更多
关键词 semi-rigid carboxylic acid ligands three-dimensional framework tetranuclear cobalt-oxo cluster semiconductor material antiferromagnetic magnetism
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Synthesis and crystal structure of three cucurbit[6]uril-cadmium supramolecular assemblies
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作者 DING Wenya XU Fangfei +2 位作者 GU Jiayu CHEN Xinran CHEN Kai 《无机化学学报》 北大核心 2026年第4期808-816,共9页
5,5'-dithiobis(2-nitrobenzoic acid)(H_(2)DTNB)was employed as the second ligand to react with cucurbit[6]uril(Q[6])and Cd(NO_(3))_(2),and it was deprotonated or transformed into HDTNB^(-),TNB^(2-)and NSB^(2-)(H_(2... 5,5'-dithiobis(2-nitrobenzoic acid)(H_(2)DTNB)was employed as the second ligand to react with cucurbit[6]uril(Q[6])and Cd(NO_(3))_(2),and it was deprotonated or transformed into HDTNB^(-),TNB^(2-)and NSB^(2-)(H_(2)TNB=5,5'-thiobis(2-nitrobenzoic acid),H_(2)NSB=2-nitro-5-sulfobenzoic acid)under different conditions to afford three novel supramolecular assemblies with the formulas of[Cd(H_(2)O)_(4)(Q[6])](HDTNB)_(2)·3H_(2)O(1),[Cd(H_(2)O)_(6)]_(2)(TNB)_(2)·Q[6]·4H_(2)O(2)and[Cd(H_(2)O)_(5)(NSB)]_(2)·Q[6](3).Singe-crystal diffraction(SC-XRD)analysis revealed that assembly 1 is constructed from 2D[Cd(H_(2)O)_(4)(Q[6])]2+supramolecular layers and HDTNB^(-)supra molecular layers,the structure of assembly 2 is comprised of the 2D{[Cd(H_(2)O)_(6)]_(2)·Q[6]}^(4+)supramolecular layers and 1D TNB^(2-)supramolecular chains,while assembly 3 is built from the 3D Q[6]frameworks with[Cd(H_(2)O)_(5)(NSB)]supramolecular chains filled in the pores.Meanwhile,the noncovalent interactions between the ligands HDTNB^(-)/TNB^(2-)/NSB^(2-)and the outer-surface of Q[6]molecules contributed greatly to the formation of the supramolecular architecture of assemblies 1-3.CCDC:2522253,1;2522254,2;2522255,3. 展开更多
关键词 supramolecular assembly uril CADMIUM crystal structure 5 5'-dithiobis(2-nitrobenzoic acid)
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Synthesis,structure,and properties of hydrated tricyclohexyltin theophylline-7-acetic acid complex
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作者 HE Lifang LUO Yaoze +3 位作者 SHI Qiying TANG Jianxin ZHANG Fuxing ZHU Xiaoming 《无机化学学报》 北大核心 2026年第3期632-640,共9页
The hydrated tricyclohexyltin theophylline-7-acetic acid(tpH)complex[Sn(C_(6)H_(11))_(3)(tp)(H_(2)O)]was synthesized via an ethanol solvothermal method using tricyclohexyltin hydroxide and tpH in a 1∶1 molar ratio.Th... The hydrated tricyclohexyltin theophylline-7-acetic acid(tpH)complex[Sn(C_(6)H_(11))_(3)(tp)(H_(2)O)]was synthesized via an ethanol solvothermal method using tricyclohexyltin hydroxide and tpH in a 1∶1 molar ratio.The complex was characterized by IR,^(1)H(^(13)C)NMR,elemental analysis,and powder X-ray diffraction,and the crystal structure was determined by single-crystal X-ray diffraction.The crystal belongs to the orthorhombic system with space group Iba2,and the central tin atom is in a five-coordinated trigonal bipyramidal configuration.Quantum chemistry ab initio calculations were performed to investigate the stability,molecular orbital energy,and frontier molecular orbital characteristics of the complex.Additionally,its thermal stability,electrochemical properties,and in vitro anticancer activity were evaluated.CCDC:2380308. 展开更多
关键词 hydrated tricyclohexyltin theophylline-7-acetic acid complex SYNTHESIS crystal structure in vitro antitumor activity
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Thermodynamic Correlation Between Surface Carboxyl Configuration and Wettability
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作者 GUO Zhuohuan WANG Dayang 《高等学校化学学报》 北大核心 2026年第1期255-266,共12页
In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using at... In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using attenuated total reflectance Fourier-transform infrared spectroscopy(ATR-FTIR),the molecular configurations of surface carboxyl groups(COOH),free carboxyl(COOH_(f))and hydrogen-bonded carboxyl(COOH_(HB),were directly correlated with the polar component of surface energy(γ^(s,p)).By decomposing theγ^(s,p)values of the PAA thin films as a sum of the contributions of COOH_(f)and COOH_(H B),the intrinsic polar component of surface energy of COOH_(H B)(γ_(H B)^(s,p*))was quantified for the first time as 8.34 mN/m,significantly lower than that of COOH_(f)(γ_(f)^(s,p*)=34 mN/m).This result highlights that hydrogen bonding markedly reduces theγ^(s,p),providing a rational explanation for the relatively large water contact angle observed on PAA thin films.Furthermore,it establishes a thermodynamic basis for estimating the fraction of surface COOH_(H B)groups(f H B)from wettability measurements.Further extension of the model to carboxyl-terminated self-assembled monolayers(COOH-SAMs)revealed that surface COOH density(ΣCOOH)critically regulates wetting behavior:whenΣCOOH ranges from 4.30 to 5.25 nm^(-2),COOH groups predominantly exist in a free state and facilitate effective hydration layers,thereby promoting superhydrophilicity.Overall,this study not only establishes a unified thermodynamic framework linking surface COOH configurations to macroscopic wettability,but also validates its universality by extending it to COOH-SAMs systems,thereby providing a unified theoretical framework for the controllable design of hydrophilicity in various COOH-functionalized surfaces. 展开更多
关键词 Polyacrylic acid film Hydrogen bonding Attenuated total reflectance Fourier-transform infrared spectroscopy Quantitative carboxyl configuration Polar component of surface energy
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Intervention effect and mechanism of Compound Herba Gueldenstaedtiae in a mouse model of breast hyperplasia
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作者 Wu Yilin Tian Hongying +8 位作者 Sun Jiale Jiao Jiajia Zhao Zihan Shao Jinhuan Zhao Kaiyue Zhou Min Li Qian Li Zexin Yue Changwu 《中国组织工程研究》 北大核心 2026年第17期4377-4389,共13页
BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probi... BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia. 展开更多
关键词 Herba Gueldenstaedtiae traditional Chinese medicine compound mice with breast hyperplasia microbial fermentation gut microbiota network pharmacology short-chain fatty acids hormone levels inflammatory response endocrine disorders
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Highly sensitive and multi-response Zn-MOF fluorescence sensor: Design, synthesis, and detection of 4-nitrophenol, Cu^(2+), and pyrimethanil
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作者 LIU Fan CHEN Xiaoli +4 位作者 REN Jing LEI Yantao CUI Huali YANG Hua WANG Jijiang 《无机化学学报》 北大核心 2026年第4期872-882,共11页
Based on 4'-(1H-tetrazol-5-yl)-[1,1'-biphenyl]-2,4,6-tricarboxylic acid(H_(4)bta)ligand,zinc metal-organic framework(Zn-MOF):{[Zn_(2)(bta)(bpy)_(2)(H_(2)O)]·1.5H_(2)O}_(n)(bpy=2,2'-bipyridine)was desi... Based on 4'-(1H-tetrazol-5-yl)-[1,1'-biphenyl]-2,4,6-tricarboxylic acid(H_(4)bta)ligand,zinc metal-organic framework(Zn-MOF):{[Zn_(2)(bta)(bpy)_(2)(H_(2)O)]·1.5H_(2)O}_(n)(bpy=2,2'-bipyridine)was designed and synthesized by hydrothermal method.Its structure was characterized by elemental analysis,IR spectra,X-ray single crystal diffraction,etc.The asymmetric unit of Zn-MOF contains two crystallographically independent Zn^(2+)ions.Through the connection of Zn^(2+)ions via H_(4)bta,a 1D double-layer network structure is formed.Adjacent double-layer networks further form a 2D supramolecular network through hydrogen bonding.Notably,Zn-MOF exhibited excellent fluorescence properties and could efficiently and sensitively detect various water pollutants:4-nitrophenol(4-NP),Cu^(2+),and pyrimethanil(Pth).Additionally,the mechanism of fluorescence sensing was investigated.CCDC:2432230. 展开更多
关键词 4'-(1H-tetrazol-5-yl)-[1 1'-biphenyl]-2 4 6-tricarboxylic acid crystal structure fluorescence sensing
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Dioscorea bulbifera L.induces liver injury in mice partly through bile acids metabolic disorders and gut microbiota dysbiosis mediated by the YY1-FXR/Nrf2 signaling pathway
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作者 Bo-Shen Zhao Yun-Dong Xie +8 位作者 Xin Wang Yu-Han Zhang Hong-Zhe Zhu Lei-Lei Shi Hui-Zi Shangguan Ling Ding Shu-Hong Zhu Cui-Cui Ren Ji-Ping Liu 《Traditional Medicine Research》 2026年第8期15-27,共13页
Background:This study aimed to comprehensively elucidate the hepatotoxic effects of Dioscorea bulbifera L.(DBL)in mice and to explore the underlying molecular mechanisms.Methods:Mice were administered different doses ... Background:This study aimed to comprehensively elucidate the hepatotoxic effects of Dioscorea bulbifera L.(DBL)in mice and to explore the underlying molecular mechanisms.Methods:Mice were administered different doses of DBL via intragastric gavage for 21 days.Organ indices of multiple organs were then measured,and histopathological changes were systematically evaluated.Particular attention was paid to biochemical markers and hepatic histopathological alterations associated with liver injury.Subsequently,the composition of the gut microbiota in colonic contents was analyzed using 16S rDNA sequencing,and the levels of short-chain fatty acids(SCFAs)were determined by gas chromatography(GC).Furthermore,protein expression levels of YinYang 1(YY1),Farnesoid X Receptor(FXR),Nuclear factor erythroid 2-related factor 2(Nrf2),and bile acids(BAs)-related proteins in the liver were assessed by Western blot analysis.Results:Our findings revealed that DBL induced varying degrees of multi-organ toxicity in mice,with the most pronounced hepatotoxicity observed.Liver injury was induced in a dose-dependent manner,accompanied by increased hepatic inflammation and oxidative stress,as well as enhanced hepatocyte apoptosis.Furthermore,DBL may modulate the YY1-FXR/Nrf2 signaling pathway,leading to upregulation of BAs-related proteins such as cholesterol 7α-hydroxylase(CYP7A1),while downregulating other BAs-related proteins,including sodium taurocholate cotransporting polypeptide(NTCP),bile salt export pump(BSEP),multidrug resistance protein 2(MRP2),and P-glycoprotein(P-gp).These changes promoted excessive BAs synthesis and impaired the excretion and reabsorption of BAs,ultimately disturbing BAs homeostasis.Additionally,DBL induces gut microbiota dysbiosis and reduces SCFAs production,leading to intestinal damage and disruption of intestinal barrier integrity.Conclusion:DBL-induced hepatotoxicity may be associated with altered expression of the YY1-FXR/Nrf2 signaling pathway and BAs–related proteins,accompanied by increased hepatic BAs accumulation and gut microbiota dysbiosis. 展开更多
关键词 DIOSCOREA bulbifera L. liver injury BILE ACIDS metabolism gut microbiota short-chain fatty ACIDS
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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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