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Boosted Biodegradability and Tribological Properties of Mineral Base Oil by Methyl Diethanolamine Fatty Acid Esters 被引量:2
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作者 Ding Jianhua Fang Jianhua +3 位作者 Chen Boshui Zhang Nan Fan Xingyu Zheng Zhe 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第4期117-124,共8页
Methyl diethanolamine fatty acid esters, viz. methyl diethanolamine octanoate and methyl diethanolamine oleate,were prepared. Their impacts on the biodegradability and tribological properties of mineral base oil 400 S... Methyl diethanolamine fatty acid esters, viz. methyl diethanolamine octanoate and methyl diethanolamine oleate,were prepared. Their impacts on the biodegradability and tribological properties of mineral base oil 400 SN were evaluated by a tester for fast evaluating the biodegradability of lubricants and by a four-ball tester, respectively. The results showed that methyl diethanolamine octanoate and methyl diethanolamine oleate both could markedly promote the biodegradation of the oil and improved its tribological properties. The improvement of biodegradability was attributed to the enhanced growth and quantity of microbes by methyl diethanolamine fatty acid esters. The worn surfaces were analyzed by a scanning electron microscope(SEM) equipped with an energy dispersive spectrometer(EDS) and an X-ray photoelectron spectroscope(XPS). The results indicated that the enhancement of friction-reducing and anti-wear properties of the mineral oil was attributed to the formation of complicated boundary lubrication films composed of species such as Fe_2O_3, Fe_3O_4 and organic nitrogen-containing compounds with a structure of –C-N-or R-NH_2. 展开更多
关键词 BIODEGRADATION wear friction METHYL DIETHANOLAMINE fatty acid esters
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Synthesis and Primary Research on Antitumor Activity of Three New Panaxadiol Fatty Acid Esters 被引量:2
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作者 ZHANG Chun-hong LI Xiang-gao +2 位作者 GAO Yu-gang ZHANG Lian-xue FU Xue-qi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第2期176-182,共7页
For making use of Ginseng resources that exhibit an antitumor activity and for finding new anticancer drugs, three new fatty acid ester compounds: 3/β-acetoxy panaxadiol ( Ⅰ ), 3β-palmitic acid aceloxy panaxadi... For making use of Ginseng resources that exhibit an antitumor activity and for finding new anticancer drugs, three new fatty acid ester compounds: 3/β-acetoxy panaxadiol ( Ⅰ ), 3β-palmitic acid aceloxy panaxadiol ( Ⅱ ) , and 3β-octadecanoic acid aceloxy panaxadiol( Ⅰ , Ⅱ, and m) were synthesized with panaxadiol, diacetyl oxide, palmityl chloride and stearyl chloride, and their structures were determined via MS, ^13C NMR, IR, TLC, and so on. The molar yields of the three compounds are 75.14%, 79. 08%, and 72. 57%, respectively. Meanwhile, the antitumor activity of the three new panaxadiol fatty acid ester derivatives and panaxadiol was compared by using the method of MTT. Tumor cell used was Vero cell line. Positive control was 5-FU, blank was an RPMI1640 culture medium, negative control was an RPMI1640 culture medium and the solvent for drugs to be tested. Compound Ⅰ has the strongest antitumor activity followed by panaxadiol; compounds Ⅱ and Ⅲ have similar and weakest antitumor activities. Furthermore, the antitumor activities of the panaxadiol fatty acid ester derivatives show positive correlation with the concentration of the test group, but show no relationship with the molecular weight of fatty acid. The methods that are used to synthesize the three compounds with high yields and strong antitumor activities are simple and show a great potential for meeting the needs of industrial manufacture of these drugs. 展开更多
关键词 SYNTHESIS Panaxadiol fatty acid esters Anti-tumor activity
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Epoxidation of Unsaturated Fatty Acid Methyl Esters in the Presence of SO_3H-functional Brφnsted Acidic Ionic Liquid as Catalyst 被引量:15
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作者 蔡双飞 王利生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第1期57-63,共7页
The epoxidation of unsaturated fatty acid methyl esters(FAMEs)by peroxyacetic acid generated in situ from hydrogen peroxide and acetic acid was studied in the presence of SO3H-functional Brnsted acidic ionic liquid (I... The epoxidation of unsaturated fatty acid methyl esters(FAMEs)by peroxyacetic acid generated in situ from hydrogen peroxide and acetic acid was studied in the presence of SO3H-functional Brnsted acidic ionic liquid (IL)[C3SO3HMIM][HSO4]as catalyst.The effects of hydrogen peroxide/ethylenic unsaturation ratio,acetic acid concentration,IL concentration,recycling of the IL catalyst,and temperature on the conversion to oxirane were studied.The kinetics and thermodynamics of unsaturated FAMEs epoxidation and the kinetics of oxirane cleavage of the epoxidized FAMEs by acetic acid were also studied.The conversion of ethylenic unsaturation group to oxirane, the reaction rate of the conversion to oxirane,and the rate of hydrolysis(oxirane cleavage)were higher by using the IL catalyst. 展开更多
关键词 不饱和脂肪酸 酸性离子液体 催化剂 脂肪酸甲酯 反应动力学 环氧乙烷 过氧化氢 白细胞介素
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Preparation of Highly Concentrated Silver Nanoparticles in Reverse Micelles of Sucrose Fatty Acid Esters through Solid-Liquid Extraction Method 被引量:4
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作者 Hidetaka Noritomi Yoshihiro Umezawa +1 位作者 Saori Miyagawa Satoru Kato 《Advances in Chemical Engineering and Science》 2011年第4期299-304,共6页
Silver nanoparticles were synthesized in reverse micelles consisting of sucrose fatty acid esters by dissolving reactant powder in the water pool of reverse micelles through the solid-liquid extraction. Silver nanopar... Silver nanoparticles were synthesized in reverse micelles consisting of sucrose fatty acid esters by dissolving reactant powder in the water pool of reverse micelles through the solid-liquid extraction. Silver nanoparticles having various sizes and shapes were obtained at high concentration. The size of silver nanoparticles was controlled by reaction temperature. Moreover, the size of silver nanoparticles was dependent upon the average esterification degree of sucrose fatty acid esters forming reverse micelles. The wavelength in the peaks, which corresponded upon the localized surface plasmon resonance of resultant silver nanoparticles, was correlated with their sizes. 展开更多
关键词 Reverse MICELLE Silver Nanoparticle Size Control SOLID-LIQUID Extraction SUCROSE fatty acid ester
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Enzymatic synthesis, antioxidant ability and oil-water distribution coefficient of troxerutin fatty acid esters 被引量:1
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作者 Yongmei Xiao Ming Li +2 位作者 Pu Mao Liangru Yang Lingbo Qu 《Grain & Oil Science and Technology》 2019年第3期78-84,共7页
Troxerutin fatty acid esters were prepared using troxerutin and fatty acid vinyl esters as substrates in pyridine through enzymatic route. The structures of as-prepared compounds were identified by FT-TR, NMR, and ESI... Troxerutin fatty acid esters were prepared using troxerutin and fatty acid vinyl esters as substrates in pyridine through enzymatic route. The structures of as-prepared compounds were identified by FT-TR, NMR, and ESI-HRMS. Using alkaline protease(≥30 mg/mL) as enzyme, maximum yields reached 58% at 3:1(vinyl hexanoate to troxerutin) in pyridine(water content ≤1%). The yields gradually declined as chain length of acyl donors rose. The antioxidation abilities of the as-obtained compounds were confirmed by both DPPH free radical scavenging and potassium ferricyanide reduction methods. The antioxidation ability of troxerutin fatty acid esters was found lower than that of troxerutin. However, the logP values of troxerutin fatty acid esters varied from 0.15 to 1.94, suggesting that troxerutin fatty acid esters had better lipophilicity than troxerutin(logP =-2.12) when compared to their oil-water distribution coefficients. Overall, these findings look promising as reference for further development of future troxerutin. 展开更多
关键词 TROXERUTIN ENZYMATIC synthesis fatty acid esters ANTIOXIDATION Oil-water distribution COEFFICIENT
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Optimization of Wax Esters Production from Palm Fatty Acid Distillate and Oleyl Alcohol over Amberlyst 15 被引量:1
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作者 M. Tapanwong V. Punsuvon 《Journal of Environmental Science and Engineering》 2011年第11期1427-1434,共8页
关键词 长链脂肪酸 棕榈油 油醇 蜡酯 生产 合成脂肪酸 优化 中心复合设计
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Emulsification Properties of Lactose Fatty Acid Esters
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作者 Seung-Min Lee Ashwini Wagh +1 位作者 Guneev Sandhu Marie K. Walsh 《Food and Nutrition Sciences》 2018年第12期1341-1357,共17页
Sugar fatty acid esters (SFAE) are a class of synthetic emulsifiers used in the food, pharmaceutical, and personal care industries. The influence of the fatty acid chain length on the emulsification properties of lact... Sugar fatty acid esters (SFAE) are a class of synthetic emulsifiers used in the food, pharmaceutical, and personal care industries. The influence of the fatty acid chain length on the emulsification properties of lactose fatty acid esters (LFAE) including lactose monooctanoate (LMO), lactose monodecanoate (LMD), lactose monolaurate (LML) and lactose monomyristate (LMM) was investigated in this study. The stability of the emulsions as well as the oil droplet size distribution in 20% soybean oil-in-water emulsions was measured at 0.1%, 0.25% and 0.5% of LFAE concentrations. In order of LFAE with the strongest emulsion stabilization characteristics were LML, LMD, LMO and LMM. Oil droplet distributions resulted in the same trend, with LML and LMD maintaining the smallest droplet sizes and thus the most stable emulsion. The hydrophilic-lipophilic balance (HLB) and critical micelle concentrations were determined for each LFAE. An increase in HLB value was seen with an increased CMC value for each LFAE, showing the strength of the linear relationship between these two measured values. Additionally, there was a decrease in HLB and CMC values with a decrease in the fatty acid chain length of each LFAE. This research showed that LML and LMD formed more stable emulsions, even with HLB and CMC values higher than those of LMM suggesting HLB and CMC values alone do not predict emulsifier effectiveness. 展开更多
关键词 LACTOSE fatty acid esters Emulsions EMULSION Stability SUGAR esters
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Synthesis, Crystal Structure, and Herbicidal Activity of(3R,4R)-4,7,7-Trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol Mono-fatty Acid Esters
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作者 黄道战 蓝虹云 +1 位作者 卢建芳 周艳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第2期263-272,167,共11页
Four mono-fatty acid esters(Ia~d) were synthesized via the esterification of(3R,4R)-4,7,7-trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol(I) with fatty acid chlorides(CH_3(CH_2)_nCOCl, n = 0, 2, 4, 6) and structurally c... Four mono-fatty acid esters(Ia~d) were synthesized via the esterification of(3R,4R)-4,7,7-trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol(I) with fatty acid chlorides(CH_3(CH_2)_nCOCl, n = 0, 2, 4, 6) and structurally characterized by means of H RMS, IR, ~1 H-NMR, ^(13)C-NMR and X-ray diffraction. Compounds Ia~d all belong to monoclinic system, P2_1/c space group. Intermolecular O(2)–H(2)···O(1) hydrogen bonds, intramolecular O(2)–H(2)···O(3) hydrogen bonds and van der Waals' interaction between fatty acid ester groups link each of the mono-fatty acid ester molecules into a bilayer structure similar to liposome with the exposed hydrophobic moiety and the sandwiched lipophilic moiety. Especially, compounds Ia~d could be dissoluble or scattered in aqueous solution and showed hydrophilic/lipophilic property-dependent herbicidal activity against the dicotyledon plant rape(Brassica campestris) and the monocotyledon plant barnyard grass(Echinochloa crus galli). At the concentration of 10 mmol·L^(-1), the inhibition rates of compounds Ia~d against the root growth of rape are 31.9, 90.8, 99.5 and 100%, respectively and the inhibition rates against the shoot elongation of barnyard grass are 19.3, 50.0, 80.2 and 100%, respectively. 展开更多
关键词 MONOTERPENE oxabicyclodiol mono-fatty acid ester crystal structure hydrophilic-lipophilic property herbicidal activity
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Studies on Production of Biodiesel by Esterification of Fatty Acids by a Lipase Preparation from Candida sp. 99-125 被引量:8
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作者 DENG Li(邓利) +5 位作者 NIE Kaili(聂开立) WANG Fang(王芳) TAN Tianwei(谭天伟) 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第4期529-534,共6页
A self-made lipase preparation from Candida sp. 99-125 was used for the production of biodiesel through enzymatic esterification of fatty acids. The crude lipase powder and fermentation broth were immobilized on a che... A self-made lipase preparation from Candida sp. 99-125 was used for the production of biodiesel through enzymatic esterification of fatty acids. The crude lipase powder and fermentation broth were immobilized on a cheap fiber cloth carrier. The conditions of lipase-catalyzed esterification between long-chain fatty acids and methanol in a solvent system were investigated in detail, including the temperature, pH value, substrate concentration, solvent, absorbent agent, enzyme dosage and purity, immobilization method, the mode of addition of substrate. The results show that reaction temperature, pH of lipase micro-environment, substrate concentration, enzyme dosage and purity affect the esterification strongly. Several new methods and enzymatic procedures for improving the enzymatic reaction involving the process cost are also discussed, such as fossil diesel fuel as reaction solvent, immobilization method, multi-step gradient addition of methanol. The esterification degree of 92.8% was obtained with oleic acid and methanol under the optimal reaction condition after 12.5 h reaction time. The half-life of the immobilized lipase preparation from crude free lipase powder for esterification was 15 days. 展开更多
关键词 生物柴油 酯化反应 假丝酵母 脂肪酶 合成方法
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Investigation of <i>β</i>-Cryptoxanthin Fatty Acid Ester Compositions in Citrus Fruits Cultivated in Japan 被引量:1
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作者 Yusuke Wada Atsuki Matsubara +6 位作者 Takato Uchikata Yugo Iwasaki Satoshi Morimoto Katsuta Kan Tetsuya Ookura Eiichiro Fukusaki Takeshi Bamba 《Food and Nutrition Sciences》 2013年第9期98-104,共7页
In this study, a catalog of β-cryptoxanthin (βCX) and its fatty acid esters (βCXFAs) in citrus fruits were constructed. The peel and pulp of citrus fruits from nine Japanese cultivars and one foreign cultivar were ... In this study, a catalog of β-cryptoxanthin (βCX) and its fatty acid esters (βCXFAs) in citrus fruits were constructed. The peel and pulp of citrus fruits from nine Japanese cultivars and one foreign cultivar were surveyed by supercritical fluid chromatography/triple quadrupole mass spectrometry (SFC/QqQMS). In each citrus sample, the major components were βCX and its laurate ester, myristate ester, palmitate ester, and oleate ester. However, the composition ratio of βCXFA varied with the citrus breed and between the pulp and the peel of the fruit in most cultivars. The SFC/QqQMS system could be used to obtain new information about βCXs and carry out further discussion on the feature and tendency of each citrus variety. 展开更多
关键词 β-Cryptoxanthin fatty acid ester Supercritical Fluid Chromatography
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Effects of Yttrium Doping on the Performance of Ru-Based Catalysts for Hydrogenation of Fatty Acid Methyl Ester 被引量:1
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作者 Qi Lin Huirong Zheng +2 位作者 Guocai Zheng Xinzhong Li Benyong Lou 《International Journal of Organic Chemistry》 2014年第4期219-224,共6页
The highly dispersed supported ruthenium-yttrium (Ru-Y) bimetallic catalysts were prepared by impregnation method and their catalytic performance for hydrogenation of ester was fully investigated. The catalyst was cha... The highly dispersed supported ruthenium-yttrium (Ru-Y) bimetallic catalysts were prepared by impregnation method and their catalytic performance for hydrogenation of ester was fully investigated. The catalyst was characterized by X-ray diffraction and field emission scanning electron microscopy. The results show that the average particle diameter of the bimetallic crystallites was less than 10 nm. The effects of the reaction temperature, the hydrogen pressure, the amount of catalyst and the proportion of yttrium in catalyst on the hydrogenation of ester were studied. The experimental results show that the introduction of yttrium not only changed the chemical and textural properties of ruthenium-based catalyst but also controlled the formation of Ru-Y alloy. The Ru-Y catalyst (Ru-2%Y/TiO2) exhibited high catalytic activity and good selectivity towards the higher alcohols. Under optimal reaction conditions of 240°C and 5 MPa hydrogen pressure, the conversion of palm oil esters was above 93.4% while the selectivity towards alcohol was above 99.0%. 展开更多
关键词 Yttrium-Doped Ruthenium-Based Catalyst fatty acid Methyl ester HYDROGENATION
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Ring Opening of Epoxy Fatty Esters by Nucleophile to Form the Derivatives of Substituted <i>β</i>-Amino Alcohol
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作者 Himani Varshney Aiman Ahmad Abdul Rauf 《Food and Nutrition Sciences》 2013年第9期21-24,共4页
The nucleophilic ring opening of epoxy fatty esters was carried out using the amino-1,2,4-triazole to yield substituted derivatives of β-amino alcohol. The synthesis of the substituted beta amino alcohols has been ac... The nucleophilic ring opening of epoxy fatty esters was carried out using the amino-1,2,4-triazole to yield substituted derivatives of β-amino alcohol. The synthesis of the substituted beta amino alcohols has been achieved by refluxing equimolar quantities of long chain epoxy esters (epoxy fatty esters) and 4-amino-1,2,4-triazole in dichloromethane to yield following compounds, methyl 10-(4'-amino-1',2',4'-triazole)-11-hydroxy undecanoate (V), methyl 9-(4'-amino-1', 2',4'-triazole)-10-hydroxy octadecanoate (VI), methyl 9-(4'-amino-1',2',4'-triazole)-10,12-dihydroxy octadecanoate (VII), methyl 12-(4'-amino-1',2',4'-triazole)-9,13-dihydroxy octadecanoate (VIII). Epoxides of esters of fatty acids were obtained by reaction of esters of fatty acids with mchloroperbenzoic acid. All the newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectrometry. 展开更多
关键词 TRIAZOLE EPOXIDE of ester of fatty acid Ring Opening
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Artificial Triterpenoid Fatty Acid Ester Isolated From the Leaves of Phytolacca icosandra L
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作者 Elier Galarraga Andersson Mavares +2 位作者 Neudo Urdaneta Rafael ERodríguez-Lugo Juan Manuel Amaro-Luis 《Natural Products and Bioprospecting》 CAS 2020年第4期221-225,共5页
The methanol extract form the leaves of Phytolacca icosandra L.,afforded the unprecedented artificial triterpenoid fatty acid ester 1 derived from the new natural triterpenoid phytolaccagenic acid 3-O-myristate(1a),al... The methanol extract form the leaves of Phytolacca icosandra L.,afforded the unprecedented artificial triterpenoid fatty acid ester 1 derived from the new natural triterpenoid phytolaccagenic acid 3-O-myristate(1a),along with the three known triterpenoids serjanic,acinosolic and phytolaccagenic acid(2-4).Their structures were stablished by HR-EI-MS,1D and 2D NMR techniques.The possible mechanistic formation of 1 is proposed,and the in vitro toxicity of all compounds was assessed using the brine shrimp lethality assay(BSLA). 展开更多
关键词 Phytolacca icosandra.triterpenoid fatty acid ester NMR artificial products BSLA
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Ternary Liquid-Liquid Equilibrium for Systems of Fatty Acid Methyl Ester(Methyl Palmitate/Methyl Stearate)+Ethanol+Glycerol at Atmospheric Pressure
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作者 夏淑倩 罗慧娟 马沛生 《Transactions of Tianjin University》 EI CAS 2015年第5期392-399,共8页
Liquid-liquid equilibrium data of two ternary systems methyl palmitate+ethanol+glycerol and methyl stearate+ethanol+glycerol at(318.2 and 333.2)K and atmospheric pressure were measured. The values of distribution coef... Liquid-liquid equilibrium data of two ternary systems methyl palmitate+ethanol+glycerol and methyl stearate+ethanol+glycerol at(318.2 and 333.2)K and atmospheric pressure were measured. The values of distribution coefficient and selectivity were calculated, which indicates that glycerol can be separated from fatty acid ester by using ethanol as an extraction solvent. The consistency of the isothermal tie-line data were checked by the Othmer-Tobias equation. The correlation coefficients R2 are higher than 0.993,9 for all the fitted curves. The NRTL activity coefficient model was applied to the correlation of the measured tie-line data. The root mean square deviation(RMSD)values are less than 0.007 for all the systems, which shows a good predictive capability of this model for such systems. 展开更多
关键词 棕榈酸甲酯 脂肪酸甲酯 硬脂酸甲酯 大气压力 三元液液平衡 甘油 乙醇 系统
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Reduced lysosomal acid lipase activity: A new marker of liver disease severity across the clinical continuum of non-alcoholic fatty liver disease? 被引量:2
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作者 Francesco Baratta Daniele Pastori +5 位作者 Domenico Ferro Giovanna Carluccio Giulia Tozzi Francesco Angelico Francesco Violi Maria Del Ben 《World Journal of Gastroenterology》 SCIE CAS 2019年第30期4172-4180,共9页
Lysosomal acid lipase(LAL)plays a key role in intracellular lipid metabolism.Reduced LAL activity promotes increased multi-organ lysosomal cholesterol ester storage,as observed in two recessive autosomal genetic disea... Lysosomal acid lipase(LAL)plays a key role in intracellular lipid metabolism.Reduced LAL activity promotes increased multi-organ lysosomal cholesterol ester storage,as observed in two recessive autosomal genetic diseases,Wolman disease and Cholesterol ester storage disease.Severe liver steatosis and accelerated liver fibrosis are common features in patients with genetic LAL deficiency.By contrast,few reliable data are available on the modulation of LAL activity in vivo and on the epigenetic and metabolic factors capable of regulating its activity in subjects without homozygous mutations of the Lipase A gene.In the last few years,a less severe and non-genetic reduction of LAL activity was reported in children and adults with non-alcoholic fatty liver disease(NAFLD),suggesting a possible role of LAL reduction in the pathogenesis and progression of the disease.Patients with NAFLD show a significant,progressive reduction of LAL activity from simple steatosis to non-alcoholic steatohepatitis and cryptogenic cirrhosis.Among cirrhosis of different etiologies,those with cryptogenic cirrhosis show the most significant reductions of LAL activity.These findings suggest that the modulation of LAL activity may become a possible new therapeutic target for patients with more advanced forms of NAFLD.Moreover,the measurement of LAL activity may represent a possible new marker of disease severity in this clinical setting. 展开更多
关键词 Non-alcoholic fatty liver DISEASE Non-alcoholic steatohepatitis LYSOSOMAL acid lipase Cirrhosis Wolman DISEASE Cholesterol ester storage DISEASE
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Factors aff ecting lipid and fatty acid composition of Calanus sinicus in the Yellow Sea and the East China Sea in spring 被引量:1
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作者 Yanqing WANG Zhencheng TAO +1 位作者 Chaolun LI Mengtan LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第1期173-182,共10页
The factors aff ecting lipid and fatty acid composition of copepod Calanus sinicus in the Yellow Sea(YS)and the East China Sea(ECS)were examined in this study.In spring,there were signifi cant diff erences between the... The factors aff ecting lipid and fatty acid composition of copepod Calanus sinicus in the Yellow Sea(YS)and the East China Sea(ECS)were examined in this study.In spring,there were signifi cant diff erences between these two regions for both environmental conditions and food availability.Such regional diff erence signifi cantly infl uenced the lipid and fatty acid profi les of C.sinicus.Our results show that C.sinicus has a higher lipids content in ECS,especially for wax ester and triglyceride lipids,indicating a more active and effi cient predation.According to BIO-ENV analysis,the variation of lipids profi les may be infl uenced majorly by water temperature.Moreover,the fatty acids(FAs)profi les of C.sinicus were also diff erent between YS and ECS,especially in the four major contributors,C22꞉1ω11,eicosapentaenoic acid(EPA),docosahexenoic acid(DHA),and C20꞉1ω9.The considerable amounts of self-biosynthesized FAs of herbivorous copepod(C22꞉1ω11 and C20꞉1ω9)and low DHA/EPA ratio may indicate that C.sinicus in ECS feed mainly on phytoplankton comparing to those in YS.The fatty acid profi les of C.sinicus were aff ected by the diff erences in food availability. 展开更多
关键词 Calanus sinicus lipid storage wax ester fatty acid composition Yellow Sea and East China Sea
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Supercritical Synthesis of Ethyl Esters via Transesterification from Waste Cooking Oil Using a Co-Solvent 被引量:1
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作者 Tapaswy Muppaneni Harvind K. Reddy Shuguang Deng 《Journal of Environmental Protection》 2015年第9期986-994,共9页
Biofuels became more promising alternative to the fossil fuels because of the depletion of fossil resources, renewability, environmental benefits, and energy security. Ethanolysis of waste cooking oil with hexane as c... Biofuels became more promising alternative to the fossil fuels because of the depletion of fossil resources, renewability, environmental benefits, and energy security. Ethanolysis of waste cooking oil with hexane as co-solvent was carried out for the production of fatty acid ethyl ester (FAEE). This process reduced the severity of process parameters with high purity biodiesel yield. Process variables such as co-solvent ratio, ethanol to oil molar ratio, reaction temperature and reaction time were optimized. The maximum biodiesel yield of 88% was obtained at ethanol/oil molar ratio of 40:1, co-solvent (hexane) to oil ratio of 0.2% (v/v), reaction temperature of 300°C in 20 min of reaction time. Fatty acid ethyl ester (biodiesel) samples produced from this process were measured and evaluated using GC-MS analytical instrument. Thermo gravimetric analysis (TGA) was also performed to examine the thermal stability of waste cooking oil, ethyl esters and fuel blends. Fuel properties of ethyl esters were determined and compared with the ASTM standards for biodiesel, regular diesel and ethyl esters from different feedstock. 展开更多
关键词 fatty acid Ethyl esters SUPERCRITICAL ETHANOLYSIS CO-SOLVENT Waste Cooking Oil
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Lipids and fatty acids in Calanus sinicus during over-summering in the southern Yellow Sea 被引量:2
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作者 王延清 李超伦 +1 位作者 刘梦坛 金鑫 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第4期874-882,共9页
Over-summering is a crucial period for Calanus sinicus in the southern Yellow Sea,where it is a key member of the zooplankton community.Lipids play an important role in copepod diapause,which is part of their over-sum... Over-summering is a crucial period for Calanus sinicus in the southern Yellow Sea,where it is a key member of the zooplankton community.Lipids play an important role in copepod diapause,which is part of their over-summering strategy.We investigated how different fatty acids and lipid classes,including wax esters,changed during over-summering of C.sinicus during three cruises in June and August 2011 and November 2010,corresponding to the pre-,during and post-diapause periods,respectively.Large amounts of lipids were accumulated,mainly wax esters as previously found in C.finmarchicus during its diapause,and most of the storage lipids were used during over-summering.Wax ester polyunsaturated fatty acids(PUFAs) showed the most variation of the fatty acids(FAs),while the percentage composition of FAs in polar lipids was relatively stable.Selective use of wax ester PUFAs has already been shown to play important roles in the winter diapause of Calanus species in other regions,and our FA results show that this is the case for the Yellow Sea Cold Bottom Water(YSCBW) population that diapauses in summer. 展开更多
关键词 多不饱和脂肪酸 中华哲水蚤 南黄海 脂质 夏天 浮游动物群落 滞育期 PUFA
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Determination of the Fatty Acid Profile of Breast Milk from Nursing Mothers in Bungoma County, Kenya
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作者 Virate J. Kiprop Amy W. Girard +2 位作者 Lilian A. Gogo Mary N. Omwamba Symon M. Mahungu 《Food and Nutrition Sciences》 2016年第8期661-670,共10页
The fatty acid profile in breast milk of nursing mothers who participated in a Cohort for Vitamin A (COVA) study at the fourth and ninth month of lactation was investigated. Breast milk samples were collected by manua... The fatty acid profile in breast milk of nursing mothers who participated in a Cohort for Vitamin A (COVA) study at the fourth and ninth month of lactation was investigated. Breast milk samples were collected by manual expression and stored at - 20°C until analysis. The fat was extracted from the milk and methylated using the American Oil Chemists’ Society (AOCS) Official Methods with modifications. The separation, identification and quantification of the fatty acid methyl esters was performed by gas chromatography coupled with mass spectrometry (GC-MS). Fat contents of human milk increased significantly between the fourth and ninth month of lactation 0.38 and 1.21 mg·mL<sup>-1</sup> respectively;P 0.05) than the average percent of the total unsaturated FAs (48.93%). Similarly, at the 9th month the percentage average of the total saturated fatty acids (15.18%) was significantly lower (P < 0.05) than the average percent of the total unsaturated FAs (31.05%). The results obtained in this study demonstrated that the fat content in breast milk significantly increased in the 9th compared to the 4th month of lactation. The fatty profile was also significantly different with the omega 6 being the dominant at the 9th month compared with the omega - 9 being dominant at the 4th month of lactation. 展开更多
关键词 fatty acid Profile Breast Milk Nursing Mothers fatty acid Methyl esters LACTATION
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硫化脂肪酸酯的合成及其在高温高压钻井液中的应用
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作者 夏小春 邹洋 +3 位作者 王志永 张紫铜 宋钰 戴媛静 《钻井液与完井液》 CAS 北大核心 2024年第3期344-349,共6页
大位移井高温储层水基钻井液在高负荷、高盐度、高温条件下,液体润滑剂的润滑性能不足,导致憋钻具、卡钻和钻具磨损等问题,实验室合成了一种硫化脂肪酸酯,将其与润滑剂复配后得到复合硫剂(QT311),添加至HTFlow高温高压水基钻井液中,能... 大位移井高温储层水基钻井液在高负荷、高盐度、高温条件下,液体润滑剂的润滑性能不足,导致憋钻具、卡钻和钻具磨损等问题,实验室合成了一种硫化脂肪酸酯,将其与润滑剂复配后得到复合硫剂(QT311),添加至HTFlow高温高压水基钻井液中,能够提升钻井液的润滑性能。通过四球试验机测试可知,添加1%QT311后,其COF能够下降64%,磨斑直径降低43%,润滑性能优于几款常用市售钻井液用润滑剂。通过电镜分析摩擦副表面,发现硫剂在摩擦过程中发生摩擦化学反应生成硫-铁极压膜,从而提升钻井液的减摩性能,且该剂在HTFlow钻井液体系中表现出优异的配伍性、抗水解性能、抗盐及抗温性能。试验结果为钻井液用润滑剂的进一步研究提供参考。 展开更多
关键词 大位移井 硫化脂肪酸酯 抗磨减摩 配伍性
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