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Pathogenic contribution of cholesteryl ester accumulation in the brain to neurodegenerative disorders
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作者 Michiko Shirane 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2099-2100,共2页
Cholesteryl esters(CEs) have been increasingly implicated in neurodegenerative disorders such as Alzheimer's disease(AD).Alois Alzheimer noted three prominent neuropathologic features in his original analysis of t... Cholesteryl esters(CEs) have been increasingly implicated in neurodegenerative disorders such as Alzheimer's disease(AD).Alois Alzheimer noted three prominent neuropathologic features in his original analysis of the AD brain:senile plaques,neurofibrillary tangles,and lipid granule accumulation.Senile plaques,which are aggregates of amyloid-beta(Aβ),and neurofibrillary tangles,which are aggregates of phosphorylated tau,have been regarded as more consistent characteristics of the AD brain compared with lipid granule accumulation and thus have been studied more intensively(Foley,2010). 展开更多
关键词 ESTERS ESTER cholesteryl
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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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Research Progress on Distribution,Sources and Ecological Effects of Phthalate in Soil
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作者 Hengrui ZHANG Shasha LIU 《Agricultural Biotechnology》 2024年第1期28-30,共3页
Phthalate esters(PAEs)are widely used as main plasticizers in plastic products,agricultural regulators,toys,and other fields.This paper reviewed the research progress on the distribution,sources,and ecological effects... Phthalate esters(PAEs)are widely used as main plasticizers in plastic products,agricultural regulators,toys,and other fields.This paper reviewed the research progress on the distribution,sources,and ecological effects of PAEs.The effects of PAEs on soil microorganisms,animals,plants and soil properties were explored in sequence,providing effective theoretical basis for future research on PAEs. 展开更多
关键词 Phthalate ester DISTRIBUTION SOURCE Ecological effect
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Chemical profiling of bioactive compounds in the methanolic extract of wild leaf and callus of Vitex negundo using gas chromatographymass spectrometry
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作者 Gunjan Garg Alok Bharadwaj +1 位作者 Shweta Chaudhary Veena Gupta 《World Journal of Experimental Medicine》 2024年第1期78-87,共10页
BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.neg... BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.negundo),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional medication.AIM To determine the existence of therapeutic components in leaf and callus extracts from wild V.negundo plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus extracts.Various growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS medium.RESULTS The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus development.The plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,respectively.CONCLUSION Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic extract.Octadecadienoic acid was the most common constituent in all samples.The maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,respectively.These findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to in-vivo.In addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also detected.All these components were only available in callus formed in-vitro.This study showed that the callus contained additional botanical characteristics compared with wild plants.Due to the presence of numerous bioactive compounds,the medical use of Vitex for various diseases has been accepted and the plant is considered an important source of therapeutics for research and development. 展开更多
关键词 Leaf extracts Callus extracts Methanolic extract Octadecadienoic acid Hexadecanoic acid Methyl ester Gas chromatography-mass spectrometry analysis
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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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Biodiesel from Palm Vegetable Oil
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作者 Bhawna Yadav Lamba Sapna Jain Shreya Jha 《Natural Resources》 2024年第2期51-60,共10页
Energy obtained from a variety of non-renewable sources is considered unsustainable. Various fossil fuels, such as petroleum, coal, and natural gas, are among these sources. The combustion of fossil fuels resulted in ... Energy obtained from a variety of non-renewable sources is considered unsustainable. Various fossil fuels, such as petroleum, coal, and natural gas, are among these sources. The combustion of fossil fuels resulted in the generation of greenhouse gases, which increased the amount of carbon dioxide in the atmosphere. Global warming and ozone layer degradation are the negative consequences. In a country like India, where consumable oils are still imported, it is sense to look at the possibility of using such unpalatable oils in CI engines that aren’t often utilized as cooking oil. Palm oil is a vegetable oil obtained from the monocarp of the oil palm’s crop. The main goal is to provide a low-cost, high-performance alternative to diesel. The possibility of palm oil as a realistic, modest, and effective hotspot for the generation of biodiesel is investigated in this research. The article is focused on the comparison of palm oil and diesel in terms of characteristics. 展开更多
关键词 BIODIESEL TRANSESTERIFICATION Palm Oil Heterogeneous Catalyst Methyl Esters Sustainable Fuel Energy
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Exploring Effective Ways of Green Printing to Reduce Harmful Volatile Organic Compounds Emissions
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作者 Yizhe Li Yao Wang 《Proceedings of Business and Economic Studies》 2024年第1期199-203,共5页
This paper delves into the transformative shift in the printing industry from traditional petroleum-based inks to sustainable alternatives,focusing on soy ink.Initially,it examines the environmental and health hazards... This paper delves into the transformative shift in the printing industry from traditional petroleum-based inks to sustainable alternatives,focusing on soy ink.Initially,it examines the environmental and health hazards associated with conventional printing,highlighting the detrimental impact of volatile organic compounds(VOCs)and toxic substances in inks.The emergence of soy ink as an eco-friendly solution is then explored.Derived from soybeans,soy ink significantly reduces the release of harmful VOCs and enhances the recyclability of printed materials.The paper discusses not only the environmental benefits of soy ink but also its operational and economic advantages,such as improved deinking capabilities and waste reduction.A notable development in soy ink technology is the use of soy methyl ester,which addresses the challenges of slow drying and penetration associated with traditional inks.The paper concludes by emphasizing the need for continued innovation in sustainable practices within the printing industry,positioning soy ink as a key player in aligning economic goals with environmental responsibility.The shift to soy-based inks exemplifies a broader trend towards sustainability,pivotal for the future health of the planet. 展开更多
关键词 Soy ink Sustainable printing Environmental impact Soy methyl ester Green innovation
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In vitro polymerization of the dopamine-borate melanin precursor:A proof-of-concept regarding^(10)boron neutron-capture therapy for melanoma 被引量:1
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作者 JUAN C.STOCKERT SILVINA A.ROMERO +1 位作者 MARCELO N.FELIX-POZZI ALFONSO BLÁZQUEZ-CASTRO 《BIOCELL》 SCIE 2023年第4期919-928,共10页
The^(10)boron neutron-capture therapy(BNCT)is an emerging antitumoral method that shows increasing biomedical interest.BNCT is based on the selective accumulation of the^(10)boron isotope within the tumor,which is the... The^(10)boron neutron-capture therapy(BNCT)is an emerging antitumoral method that shows increasing biomedical interest.BNCT is based on the selective accumulation of the^(10)boron isotope within the tumor,which is then irradiated with low-energy thermal neutrons,generating nuclear fission that produces 7lithium,4helium,andγrays.Simple catechol-borate esters have been rather overlooked as precursors of melanin biosynthesis,and therefore,a proof-of-concept approach for using dopamine-borate(DABO)as a suitable boron-containing candidate for potential BNCT is presented here.DABO can spontaneously oxidize and autopolymerize in vitro,giving a soluble,eumelaninlike brown-black poly-DABO product.Melanotic melanoma cell cultures treated with 1 mM DABO for 24 and 48 h were viable and showed no signs of damage or cell death.The stability and possible trans-esterification of DABO is shortly discussed.Chemical calculations and quantitative structure-activity relationships(QSAR)analysis of DABO and the BNCT agent BPA indicated that they should be cell permeant and accumulate within lysosomes and melanosomes.Molecular modeling allows visualization of both the DABO precursor and the structure of a borate derivative of the proposed catechol-porphycene model for eumelanin,showing interesting features from molecular orbital calculations.The main difference between DABO and other agents,such as BPA,is that it is not a boronic acid nor a boron cluster.This simple catechol-borate ester(protected from oxidation and blackening)could be administrated to living cells and organisms,in which biosynthesis of boron-melanin in melanoma melanocytes can lead to improved BNCT. 展开更多
关键词 ^(10)Boron Borate esters CATECHOLS DOPAMINE EUMELANIN MELANOMA
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Impact of endothelial nitric oxide synthase activation on accelerated liver regeneration in a rat ALPPS model
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作者 Hitoshi Masuo Akira Shimizu +7 位作者 Hiroaki Motoyama Koji Kubota Tsuyoshi Notake Takahiro Yoshizawa Kiyotaka Hosoda Koya Yasukawa Akira Kobayashi Yuji Soejima 《World Journal of Gastroenterology》 SCIE CAS 2023年第5期867-878,共12页
BACKGROUND Although the associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)induces more rapid liver regeneration than portal vein embolization,the mechanism remains unclear.AIM To assess... BACKGROUND Although the associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)induces more rapid liver regeneration than portal vein embolization,the mechanism remains unclear.AIM To assess the influence of inflammatory cytokines and endothelial nitric oxide synthase(eNOS)activation on liver regeneration in ALPPS.METHODS The future liver remnant/body weight(FLR/BW)ratio,hepatocyte proliferation,inflammatory cytokine expression,and activation of the Akt-eNOS pathway were evaluated in rat ALPPS and portal vein ligation(PVL)models.Hepatocyte proliferation was assessed based on Ki-67 expression,which was confirmed using immunohistochemistry.The serum concentrations of inflammatory cytokines were measured using enzyme linked immune-solvent assays.The Akt-eNOS pathway was assessed using western blotting.To explore the role of inflammatory cytokines and NO,Kupffer cell inhibitor gadolinium chloride(GdCl3),NOS inhibitor N-nitro-arginine methyl ester(L-NAME),and NO enhancer molsidomine were administered intraperitoneally.RESULTS The ALPPS group showed significant FLR regeneration(FLR/BW:1.60%±0.08%,P<0.05)compared with that observed in the PVL group(1.33%±0.11%)48 h after surgery.In the ALPPS group,serum interleukin-6 expression was suppressed using GdCl3 to the same extent as that in the PVL group.However,the FLR/BW ratio and Ki-67 labeling index were significantly higher in the ALPPS group administered GdCl3(1.72%±0.19%,P<0.05;22.25%±1.30%,P<0.05)than in the PVL group(1.33%±0.11%and 12.78%±1.55%,respectively).Phospho-Akt Ser473 and phospho-eNOS Ser1177 levels were enhanced in the ALPPS group compared with those in the PVL group.There was no difference between the ALPPS group treated with L-NAME and the PVL group in the FLR/BW ratio and Ki-67 labeling index.In the PVL group treated with molsidomine,the FLR/BW ratio and Ki-67 labeling index increased to the same level as in the ALPPS group.CONCLUSION Early induction of inflammatory cytokines may not be pivotal for accelerated FLR regeneration after ALPPS,whereas Akt-eNOS pathway activation may contribute to accelerated regeneration of the FLR. 展开更多
关键词 HEPATECTOMY Nitric oxide Liver regeneration CYTOKINES NG-Nitroarginine methyl ester Molsidomine
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Pollution characteristics and risk assessment of organophosphate esters in aquaculture farms and natural water bodies adjacent to the Huanghe River delta
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作者 Jinyu CHAO Song FENG +2 位作者 Yingdong HAO Jianing LIN Bin ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期251-266,共16页
To date,little attention has been paid to the effects of organophosphate esters(OPEs)pollution on aquacultural environment and aquatic product safety.Huanghe(Yellow)River delta area is one of the largest aquaculture c... To date,little attention has been paid to the effects of organophosphate esters(OPEs)pollution on aquacultural environment and aquatic product safety.Huanghe(Yellow)River delta area is one of the largest aquaculture centers in China,where ecological security protection is crucial in the national strategy of China.To explore the pollution characteristics,bioaccumulation,and health risks of OPEs in aquaculture farms in the Huanghe River delta and natural water bodies in the adjacent seas,five species of organisms from different farm types nearby the Huanghe River delta,and the corresponding culture water and sediments were sampled in this study.The total concentrations of Σ_(13)OPEs in water,sediments,and organisms were 51.53-272.18 ng/L,52.63-63.17 ng/g dry weight(dw),and 46.82-108.90 ng/g dw,respectively.Among the five types of culture ponds,the water samples from the swimming crab and hairy crab culture ponds exhibited higher OPEs,the concentration of OPEs in the sediments from the few ponds was relatively balanced,and the OPEs in the organism from the holothurian ponds was higher.Tris(1,3-dichloro-2-isopropyl pho sphate)(TDCP)was the main contaminant in water samples and tripropyl phosphate(TPrP)in sediments and organisms.However,trisphenyl phosphate(TPhP)showed the strongest bioaccumulation ability,followed by 2-ethylhexyl diphenyl phosphate(EHDPP)and TPrP.The bioaccumulation capacities of the five species were as follows:prawn>holothurian>hairy crab>swimming crab>carp.These five types of organisms,as main seafood in human consumption,were at low risk of negative impacts of pollution.However,the risk from the mixture of organophosphate flame retardants(OPFRs)still requires more attention due to the increasing consumption and production in the world. 展开更多
关键词 organophosphate esters(OPEs) aquaculture farms BIOACCUMULATION health risk assessment
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Breakdown Voltage Prediction by Utilizing the Behavior of Natural Ester for Transformer Applications
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作者 P.Samuel Pakianathan R.V.Maheswari 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期2717-2736,共20页
This research investigates the dielectric performance of Natural Ester(NE)using the Partial Differential Equation(PDE)tool and analyzes dielectric performance using fuzzy logic.NE nowadays is found to replace Mineral ... This research investigates the dielectric performance of Natural Ester(NE)using the Partial Differential Equation(PDE)tool and analyzes dielectric performance using fuzzy logic.NE nowadays is found to replace Mineral Oil(MO)due to its extensive dielectric properties.Here,the heat-tolerant Natural Esters Olive oil(NE1),Sunflower oil(NE2),and Ricebran oil(NE3)are subjected to High Voltage AC(HVAC)under different electrodes configurations.The break-down voltage and leakage current of NE1,NE2,and NE3 under Point-Point(P-P),Sphere-Sphere(S-S),Plane-Plane(PL-PL),and Rod-Rod(R-R)are measured,and survival probability is presented.The electricfield distribution is analyzed using the Partial Differential Equation(PDE)tool.NE shows better HVAC with stand capacity under all the electrodes configuration,especially in the S-S shape geometry.The exponential function is developed for the oils under different elec-trode geometry;NE shows a higher survival probability.Likewise,the most influ-ential dielectric properties such as breakdown voltage,kinematic viscosity,and water content are used to develop a Mamdani-based control system model that combines two variables to produce the surface model.The surface model indi-cates that the NE subjected for investigation is less susceptible to moisture effect and higher kinematic viscosity.Based on the surface models of PDE and fuzzy,it is concluded that NE possesses a high survival rate since its breakdown voltage does not react to changes in water content.Hence the application of NE in the transformer application is highly safe and possesses extended life. 展开更多
关键词 Power transformer fuzzy logic prediction partial differential equation natural ester exponential function
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Adsorption of Phthalic Acid Esters by Humic Acid and Its Research Progress
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作者 Ying LI Xiuqin KONG +6 位作者 Dongxia LUO Yinghai LUO Tong CHEN Fengyu WANG Huaxiu XING Fuqiang LI Miantao LEI 《Meteorological and Environmental Research》 CAS 2023年第4期63-66,共4页
Humic acid is rich in highly electronegative oxygen-containing organic functional groups,so it has high reactivity and can adsorb phthalic acid ester(PAEs)in the environment to reduce the risk of environmental polluti... Humic acid is rich in highly electronegative oxygen-containing organic functional groups,so it has high reactivity and can adsorb phthalic acid ester(PAEs)in the environment to reduce the risk of environmental pollution from PAEs.In this paper,the extraction,characterization and adsorption models of humic acid were reviewed,and the research status of adsorption of PAEs by humic acid was further summarized.Based on these,the feasibility and observable application prospect of humic acid as a cheap adsorbent were analyzed. 展开更多
关键词 Humic acid EXTRACTION CHARACTERIZATION Phthalic acid esters ADSORPTION
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Comparative analysis of volatile compounds in different muskmelon cultivars in Xinjiang based on HS-SPME-GC-MS and transcriptomics
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作者 Yingying Fan Binxin Jia +5 位作者 Xiaoqian Cao Jun Yang Xiaolong Li Weizhong He Fengjuan Liu Cheng Wang 《Food Innovation and Advances》 2023年第3期217-224,共8页
Volatile flavor has prompted a great amount of influence in acceptance and view points in fruit products.Melon(Pyrus communis)is an aromadense fruit,thus,the evaluation of volatile flavor is crucial to melon-breeding.... Volatile flavor has prompted a great amount of influence in acceptance and view points in fruit products.Melon(Pyrus communis)is an aromadense fruit,thus,the evaluation of volatile flavor is crucial to melon-breeding.The volatile compounds present in nine varieties of Xinjiang muskmelons were identified and analyzed using the headspace solid-phase microextraction and gas chromatography-mass spectrometry methods.In addition,transcriptomics were used to discover the differential genes in fatty acid degradation pathways.It was found that a total of 170 volatile substances,including 52 alcohols,41 esters,24 aldehydes,32 ketones,14 acids and seven phenols,were identified in the nine melons.Results of PCA showed that 3-nonanol,2-nonanol,bis(2-ethylhexyl)adipate,and 2-methylpropanal contributed more to the flavor of melon.It was verified that high activities of acyl-coenzyme A cholesterol acyltransferase(AAT)promoted the conversion of alcohols to esters,so that the melons have a high content of esters.Four genes of long-chain acyl-CoA synthetase were mainly responsible for the large difference in volatile substances.This practice may further undermine the primary rationale for the breeding and promotion in different cultivars of muskmelon. 展开更多
关键词 volatile ESTERS ALCOHOLS
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魔鬼爪化学成分的研究 被引量:7
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作者 戚进 周家宏 +3 位作者 陈露 陈纪军 余伯阳 邱声祥 《中国药学杂志》 CAS CSCD 北大核心 2006年第21期1613-1615,共3页
目的 研究魔鬼爪中的化学成分。方法 运用各种色谱方法进行化学成分的分离纯化,用理化方法解析其化学结构。结果 从该植物块茎中分得9个化舍物,其中1—5为苯乙醇苷类化合物,6为三萜皂苷,结构分别被鉴定为martynoside(1),6.acety... 目的 研究魔鬼爪中的化学成分。方法 运用各种色谱方法进行化学成分的分离纯化,用理化方法解析其化学结构。结果 从该植物块茎中分得9个化舍物,其中1—5为苯乙醇苷类化合物,6为三萜皂苷,结构分别被鉴定为martynoside(1),6.acetylacteoside(2),β-(3′,4′-dihydroxyphenyl)ethyl-O-α—L—rhanmopyranosyl(1→3)-′-D-glucopyranoside(3),acteoside(4)+isocteoside(5),7α,23-dihydroxytormentic acid ester glucoside(6),阿魏酸乙酯(7),二十五酸(8)及β-胡萝卜苷(9)。结论化舍物1,6,7,8均为从该植物中首次分离得到。 展开更多
关键词 魔鬼爪 化学成分 苯乙醇苷类 23-dihydroxytormentic acid ESTER GLUCOSIDE
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水体中邻苯二甲酸酯和己二酸酯的气相色谱-质谱分析方法 被引量:4
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作者 田芹 饶竹 +5 位作者 江林 宋淑玲 黄毅 佟玲 孙伟琳 郝玲玲 《分析测试学报》 CAS CSCD 北大核心 2008年第S1期106-108,110,共4页
Phthalates and adipate ester in water have been extracted with n-hexane and analyzed by gas chromatography-mass spectrometry(GC-MS).The mean recoveries ranged from 69% to 109% with their RSD range of 1.96%-10.2%.The r... Phthalates and adipate ester in water have been extracted with n-hexane and analyzed by gas chromatography-mass spectrometry(GC-MS).The mean recoveries ranged from 69% to 109% with their RSD range of 1.96%-10.2%.The research results also showed that the method presented simplicity-operating,excellent linearity and reproducibility. 展开更多
关键词 PHTHALATES ADIPATE ESTER GC-MS water
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野鸦椿的植物化学成分研究 被引量:28
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作者 董玫 广田满 《天然产物研究与开发》 CAS CSCD 2002年第4期34-37,共4页
从野鸦椿 (EuscaphisjaponecaKantiz)枝叶的甲醇提取物分离得到 6个化合物 ,通过波谱分析鉴定为 5 ,7 dihydroxy 2 methyl benzopyran 4 one(Ⅰ ) ,3,4 ,5 trihydroxy benzoicacidmethylester(Ⅱ ) ,3,7 dihydroxy 5 octanolide(Ⅲ ... 从野鸦椿 (EuscaphisjaponecaKantiz)枝叶的甲醇提取物分离得到 6个化合物 ,通过波谱分析鉴定为 5 ,7 dihydroxy 2 methyl benzopyran 4 one(Ⅰ ) ,3,4 ,5 trihydroxy benzoicacidmethylester(Ⅱ ) ,3,7 dihydroxy 5 octanolide(Ⅲ ) ,methyl 5 ,7 dihydroxy 2 (Z) octenoate(Ⅳ ) ,7 hydroxy 2 octen 5 olide(Ⅴ )和vomifoliol(Ⅵ )。 展开更多
关键词 野鸦椿 5 7-dihydroxy-2-methyl-benzopyran-4-one 3 4 5-trihydroxy-benzoic acid METHYL ester 3 7-dihydroxy-5-octanolide METHYL 5 7-dihydroxy-2(Z)-octenoate 7-hydroxy-2-octen-5-olide vomifoliol
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微波加工对附子中酯型生物碱的影响 被引量:1
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作者 邓文伟 侯大斌 《安徽农业科学》 CAS 2012年第30期14710-14712,共3页
[目的]探讨微波加工对附子中双、单酯型生物碱含量的影响,为附子新型炮制品及药食两用加工品的开发提供参考。[方法]通过正交设计、直观分析和方差分析,探讨烫漂时间(A)、干燥温度(B)和微波时间(C)对附子中双、单酯型生物碱含量的影响。... [目的]探讨微波加工对附子中双、单酯型生物碱含量的影响,为附子新型炮制品及药食两用加工品的开发提供参考。[方法]通过正交设计、直观分析和方差分析,探讨烫漂时间(A)、干燥温度(B)和微波时间(C)对附子中双、单酯型生物碱含量的影响。[结果]微波时间对双酯型生物碱含量具有极显著影响(P<0.01),对单酯型生物碱含量具有显著影响(P<0.05);烫漂时间和干燥温度仅对双酯型生物碱含量具有显著影响(P<0.05)。最佳的因素水平组合为A3B3C3,即烫漂时间为3 min,干燥温度为60℃,微波时间为5 min;在此条件下,双酯型生物碱含量为590.33μg/g,单酯型生物碱含量为802.14μg/g。[结论]微波加工能够降低附子中双酯型生物碱含量,增加单酯型生物碱含量。 展开更多
关键词 附子(RADIX ACONITI LATERALIS PRAEPARATA) 微波加工 单酯型生物碱(Single ESTER TYPE alkaloids) 双酯型生物碱(Doub-le ESTER TYPE alkaloids)
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聚丙烯中硫酯类抗氧剂的质谱分析 被引量:2
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作者 张颖 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期282-283,共2页
  采用齐格勒-钠塔催化剂使丙烯催化聚合得到聚丙烯.聚丙烯树脂本身具有优良的性能,如机械强度好,易加工成型,质量轻,成本低等,但也存在一些缺陷,如由于聚丙烯结构中存在叔碳原子,在造粒加工、贮存和使用过程中,易受热、光、氧等的作...   采用齐格勒-钠塔催化剂使丙烯催化聚合得到聚丙烯.聚丙烯树脂本身具有优良的性能,如机械强度好,易加工成型,质量轻,成本低等,但也存在一些缺陷,如由于聚丙烯结构中存在叔碳原子,在造粒加工、贮存和使用过程中,易受热、光、氧等的作用而降解,导致材料的性能降低.…… 展开更多
关键词 POLYPROPYLENE Sulphur ester antioxidants EI - MS
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2-乙酰己酸乙酯的质谱分析
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作者 张敏 田宏远 +3 位作者 岳璞 陈智群 王民昌 王明 《分析测试学报》 CAS CSCD 北大核心 2007年第z1期333-334,共2页
2-Acetyl-hexanoic acid ethyl ester is one of important derivatives.It has been used widely useful materials as anesthetics,spice,medicine and so on.The reaction liquid of acetyl-acetic acid ethyl ester with n-butane b... 2-Acetyl-hexanoic acid ethyl ester is one of important derivatives.It has been used widely useful materials as anesthetics,spice,medicine and so on.The reaction liquid of acetyl-acetic acid ethyl ester with n-butane bromide was analyzed by gas chromatograph-mass spectrometry.The results show that there are four kinds of compounds in the reaction liquid.The main yield is 2-acetyl-hexanoic acid ethyl ester,while by-products are 2-acetyl-2-butyl-hexanoic acid ethyl ester and 3-butoxy-2-butenoic acid ethyl ester. 展开更多
关键词 2-Acetyl-hexanoic acid ethyl ester GC-MS(EI)
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α-羟基-β-对甲苯磺酰氨基羧酸甲酯的质谱研究
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作者 俞振培 贺晓然 +1 位作者 赵永华 王剑波 《分析测试学报》 CAS CSCD 北大核心 2004年第z1期118-119,共2页
  氨基酸是蛋白质的基本组成单元,在有机合成及生物代谢中都是十分重要的物质.特别是α-羟基-β-氨基酸是一些重要生物活性物质的结构单元,例如著名的抗癌药紫杉醇的侧链.本文讨论5个α-羟基-β-氨基酸衍生物在EI和MALDI-TOF条件下的...   氨基酸是蛋白质的基本组成单元,在有机合成及生物代谢中都是十分重要的物质.特别是α-羟基-β-氨基酸是一些重要生物活性物质的结构单元,例如著名的抗癌药紫杉醇的侧链.本文讨论5个α-羟基-β-氨基酸衍生物在EI和MALDI-TOF条件下的质谱性质.…… 展开更多
关键词 Hydroxy - amino - acid esters MALDI - TOF - MS EI - MS
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