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Supercritical Fluid Extraction of Essential Oil from Dry Rhizome of Ligusticum chuanxiong Hort and Their Characterization by GC/MS 被引量:14
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作者 洪战英 汪学昭 +3 位作者 乐健 张东春 柴逸峰 柳正良 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第2期31-34,共4页
Supercritical fluid extraction (SFE) of essential oil from dry rhizome ofLigusticum chuanxiong Hort was developed. GC/MS was used for the determination of the composition ofessential oil. Forty-four compounds were ide... Supercritical fluid extraction (SFE) of essential oil from dry rhizome ofLigusticum chuanxiong Hort was developed. GC/MS was used for the determination of the composition ofessential oil. Forty-four compounds were identified. The conventional extraction method wasconducted in parallel for comparison. The extracts were qualitatively compared by GC/MS. The yieldsof SFE and steam distillation-extraction were 4.16 % ( v/w) and 0.8 % ( v/w), respectively.Application of SFE of zessential oil from dry rhizome of Ligustiaan chuanxiong Hort was preferable. 展开更多
关键词 supercritical fluid extraction (SFE) essential oil GC/MS
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Isolation and Extraction of Total Flavonoids from Epimedium Koreanum Nakai by Supercritical Fluid Extraction 被引量:19
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作者 LIUChun-ming ZHAOXue-liang +1 位作者 LIUZhi-qiang XINGJun-peng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期707-710,共4页
In the present paper is reported the method for the isolation and extraction of total flavonoids of Epimedium Koreanum Nakai by means of supercritical fluid extraction(SFE). By examining pressure, temperature, amounts... In the present paper is reported the method for the isolation and extraction of total flavonoids of Epimedium Koreanum Nakai by means of supercritical fluid extraction(SFE). By examining pressure, temperature, amounts of modifier and extraction time, the optimized condition of SFE is confirmed as 30 MPa and 60 ℃, with 70% ethanol as the modifier. The samples were statically extracted for 30 min, followed by dynamic extraction for 120 min at a flow rate of 6 mL/min. The quantitative analysis of total flavonoids was performed by UV-Vis spectrophotometry. Compared with the conventional method, the SFE method is more efficient, more rapid and more friendly environmentally. 展开更多
关键词 Supercritical fluid extraction(SFE) FLAVONOIDS Epimedium Koreanum Naka
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Supercritical Fluid Extraction of Total Flavonoids from Leaves of Acanthopanax Senticosus Harms 被引量:13
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作者 LIU Chun-ming ZHAO Ji-min +1 位作者 LI Hong-mei SONG Feng-rui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第2期233-236,共4页
The herbal plant Acanthopanax Senticosus Harms is natural herb of Changbaishan in Jilin Province of China, which belongs to the Araliaceae family. As the ingredients of folk medicine, it has long been used to treat a ... The herbal plant Acanthopanax Senticosus Harms is natural herb of Changbaishan in Jilin Province of China, which belongs to the Araliaceae family. As the ingredients of folk medicine, it has long been used to treat a variety of human diseases, such as cerebrovascular disease, diabetes, tumor, isochemic heart diseases, hypertension, rheumatic arthritis, etc. E2,33. Flavonoids, a class of constituent compounds, which have a broad distribution in the nature and are found in Acanthopanax Senticosus Harms, have gained particular attention. A number of studies have shown that flavonoid compounds have wide biological activities, such as anti-aging, anticancer, anti-HIV, 展开更多
关键词 Supercritical fluid extraction(SFE) Acarahopanax Senticosus Harms FLAVONOIDS
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Comparison of Constituents and Insecticidal Activities of Essential Oil from Artemisia lavandulaefolia by Steam Distillation and Supercritical-CO_2 Fluid Extraction 被引量:8
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作者 YUAN Hai-bin SHANG Li-na +1 位作者 WEI Chun-yan REN Bing-zhong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第6期888-892,共5页
Essential oil was extracted from Artemisia lavandulaefolia DC.by steam distillation(SD) and supercritical-CO2 fluid extraction(SFE),respectively.The constituents of the essentil oils extracted with those two metho... Essential oil was extracted from Artemisia lavandulaefolia DC.by steam distillation(SD) and supercritical-CO2 fluid extraction(SFE),respectively.The constituents of the essentil oils extracted with those two methods were analyzed by gas chromatography-mass spectrometry(GC-MS) and insecticidal activities of the essential oils were evaluated,then the results were compared to assess their biological activity.Thirty-one compounds were identified in the essential oil extracted by SD,and its main components were eucalyptol,α,α,4-trimethyl-3-cyclohexene-1-methanol and so on.Twenty-two compounds were identified for the essential oil extracted by SFE,and its main components were cyclodecene,n-hexadecanoic acid and so on.Six chemical compositions were all contained in the essential oils extracted by the two methods,i.e.,eucalyptol,α,α,4-trimethyl-3-cyclohexene-1-methanol,caryophyllene,[3aS-(3aα,3bβ,4β,7α,7aS)]-octahydro-7-methyl-3-methylene-4-(1-methylethyl)-1H-cyclopenta[1,3]cyclopropa-[1,2]benzene,nerolidol and(-)-Spathulenol.The fumigation toxicity of the essential oil obtained by means of SD to the adults of Sitophilus zeamais is significantly higher than that of the essential oil by means of SFE.The contact toxicity of the essential oil obtained by means of SFE to the adults of S.zeamais is higher than that of the essential oil obtained by means of SD,but the difference is not significant. 展开更多
关键词 Artemisia lavandulaefolia DC. Essential oil Supercritical-CO2 fluid extraction Steam distillation GC-MS Insecticidal activity
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Supercritical Fluid Extraction of a Novel Template from Mesoporous Zirconia and the Effect on Porous Structure 被引量:4
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作者 MA Fu ZHAO Hongjian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第6期698-700,共3页
Mesoporous zirconia was synthesized by a new and simple method. Zirconium n-propoxide was used as the zirconium source. A small, inexpensive nonsurfactant, triethanolamine, was used as the template. The template was r... Mesoporous zirconia was synthesized by a new and simple method. Zirconium n-propoxide was used as the zirconium source. A small, inexpensive nonsurfactant, triethanolamine, was used as the template. The template was removed by thermal treatment in air and supercritical fluid extraction using CO2. The structure of the resulting materials was characterized by X-ray diffraction, transmission electron microscopy, and N2 adsorption-desorption analyses. The materials are found to have narrowly distributed average pore diameters and wormhole-like pore channels. However, higher surface area and larger pore volume are exhibited after supercritical fluid extraction with CO2. The removal of the template by thermal treatment also leads to condensation and mild shrinkage of the zirconia framework. 展开更多
关键词 mesoporous zirconia TRIETHANOLAMINE STRUCTURE CALCINATION supercritical fluid extraction
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Supercritical Fluid Extraction of Saponins from Ginseng 被引量:3
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作者 LIU Chun-ming ZHAO Xue-liang +2 位作者 LI Hong-mei LIU Zhi-qiang XING Jun-peng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第6期757-760,共4页
Introduction Ginseng( Panax ginseng C. A. Meyer, Araliaceae) is one of the most valuable Chinese crude drugs and has been used widely for over 2000 years. Studies have demonstrated that ginseng can act on the centr... Introduction Ginseng( Panax ginseng C. A. Meyer, Araliaceae) is one of the most valuable Chinese crude drugs and has been used widely for over 2000 years. Studies have demonstrated that ginseng can act on the central nervous system, the cardiovascular system and the endocrine system; it can enhance immune function and metabolism; it possesses a biomodulation action, anticancer effect, anti-stress and anti-ageing activities, and so on. 展开更多
关键词 Supercritical fluid extraction(SFE) SAPONINS GINSENG
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Comparison of volatile and semivolatile compounds from commercial cigarette by supercritical fluid extraction and simultaneous distillation extraction 被引量:5
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作者 徐子刚 郑琳 《Journal of Zhejiang University Science》 EI CSCD 2004年第12期1528-1532,共5页
Supercritical carbon dioxide fluid extraction (SFE) was studied as a rapid method for extraction of volatile and semivolatile compounds of Chinese commercial cigarettes. The method was compared with simultaneous disti... Supercritical carbon dioxide fluid extraction (SFE) was studied as a rapid method for extraction of volatile and semivolatile compounds of Chinese commercial cigarettes. The method was compared with simultaneous distillation and extraction (SDE). Temperature and pressure for the SFE were optimized. The extracts obtained by the two methods showed different characters in composition and represented differently the flavor characteristics of tobacco; compared to SDE, SFE can extract compounds within a shorter time and avoid the thermal degradation and solvent contamination of samples. The extracts by the two extraction methods are complementary for investigating the flavor characteristic of tobacco products. 展开更多
关键词 Volatile and semivolatile compounds Commercial cigarette Supercritical fluid extraction (SFE) Simultaneous distillation extraction (SDE)
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Determination of polycyclic aromatic hydrocarbons with supercritical fluid extraction and chromatography(SFE/SFC) 被引量:1
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作者 Yao Weixi(Research Center for Eco - Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 , China)P. Spitzauer, A. Kettrup(Institute of Ecology Chernistry . GSF , 8042 Neuherberg, Germany) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第2期224-228,共5页
Determinationofpolycyclicaromatichydrocarbonswithsupercriticalfluidextractionandchromatography(SFE/SFC)YaoWe... Determinationofpolycyclicaromatichydrocarbonswithsupercriticalfluidextractionandchromatography(SFE/SFC)YaoWeixi(ResearchCente... 展开更多
关键词 supercritical fluid extraction (SFE) supercritical fluid chromatography (SFC) polycyclicaromauc hydrocarbons (PAHs) DETERMINATION separation
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Effect of co-existent components in CO2 supercritical fluid extract of Angelica Sinensis Radix on metabolism of Z-ligustilide after oral administration in rats 被引量:2
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作者 Bochen Zhao Qing Zhang +5 位作者 Hongmei Lin Qingguo Ru Qian Kang Hui Li Yewen Zhang Qing Wu 《Journal of Traditional Chinese Medical Sciences》 2014年第2期126-134,共9页
Objective:To establish a basis for Angelica Sinensis Radix(ASR)as a dietary supplement for colorectal cancer chemoprevention,the effect of co-existent components in supercritical fluid extract(SFE)of ASR on the pharma... Objective:To establish a basis for Angelica Sinensis Radix(ASR)as a dietary supplement for colorectal cancer chemoprevention,the effect of co-existent components in supercritical fluid extract(SFE)of ASR on the pharmacokinetics of Z-ligustilide after oral administration was investigated in vitro and in vivo.Methods:Incubation in gastrointestinal contents and incubation in rat liver tissue homogenates post-mitochondrial supernatant(PMS)experiments were used to study changes in the levels of Z-ligustilide in vitro.Results:Within 4 hours,the level of Z-ligustilide in SFE declined at a slower rate than in its pure form.Clearance of Z-ligustilide after administration in its pure form was significantly slower than that of SFE of ASR(CL,0.96±0.16 mL·min/kg versus 1.24±0.21 mL·min/kg P<0.05;AUC,243.37±16.84 versus 176.69±12.59 mg·min/L).Conclusion:These phenomena may be attributed to the interactions between the co-existent components in SFE of ASR and Z-ligustilide enhancing the stability of Z-ligustilide.These results suggest that the bioavailability of Z-ligustilide in SFE of ASR is improved.However,stabilization of plasma concentration was not sustained,so that the efficacy of active components could not be maintained.Thus,further processing of SFE of ASR is required. 展开更多
关键词 Angelica Sinensis Radix Supercritical fluid extract Z-ligustilide METABOLISM
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Hydrodynamics and Mass Transfer Performance in Supercritical Fluid Extraction Columns 被引量:1
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作者 石冰洁 张卫东 +1 位作者 张泽廷 于恩平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第6期696-700,共5页
New models for describing hydrodynamics and mass transfer performance in supercritical fluid extraction columns were proposed. Those models were proved by experimental data, which were obtained in supercritical fluid ... New models for describing hydrodynamics and mass transfer performance in supercritical fluid extraction columns were proposed. Those models were proved by experimental data, which were obtained in supercritical fluid extraction packed column, spray column and sieve tray column respectively. The inner diameter of those columns areФ25 mm. These experimental systems include supercritical carbon diox-ide-isopropanol-water and supercritical carbon dioxide-ethanol-water, in which supercritical carbon dioxide was dispersed phase, and another was continuous phase. The extraction processes were operated with continuous countercurrent flow. The predicted values are agreed well with experimental data. 展开更多
关键词 supercritical fluid extraction HYDRODYNAMICS mass transfer*
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Fast analysis of derivatives of polycyclic aromatic hydrocarbons in soil by ultra-high performance supercritical fluid chromatography after supercritical fluid extraction enrichment 被引量:2
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作者 Ye-Hua Han Li-Min Ren +5 位作者 Yan-Fen Zhang Ying-HaoWang Cheng-Long Dong Jing Xie Yu-Chi Zhang Wen Zhou 《Petroleum Science》 SCIE CAS CSCD 2021年第6期1860-1866,共7页
An efficient and environment-friendly method for simultaneous determination of 13 typical derivatives of polycyclic aromatic hydrocarbon(PAH)in petroleum-polluted soil with nitro-,oxy-and alkylfunctional group was dev... An efficient and environment-friendly method for simultaneous determination of 13 typical derivatives of polycyclic aromatic hydrocarbon(PAH)in petroleum-polluted soil with nitro-,oxy-and alkylfunctional group was developed using supercritical fluid extraction(SFE)followed by ultra-high performance supercritical fluid chromatography(UHPSFC).Parameters of UHPSFC,including type of stationary phase and mobile phase modifiers,gradient elution process,backpressure,column temperature,and the flow rate of mobile phase,were systematically optimized,achieving a fast separation within4.2 min.Limits of detection(LOD)were 0.005-0.1μg mL^(-1)or 0.1-2.0 ng g^(-1),respectively,with a good repeatability(RSD<5.0%).Before UHPSFC-PDA analysis,the PAH-derivatives in soil samples were effectively enriched in 15.0 min using SFE with an online carbon nanotubes(CNTs)collection trap.The soil samples were analyzed by the proposed method and the results were verified by GC-MS.Thus,SFE equipped with an online CNTs trap followed by UHPSFC-PDA analysis,which only consumed about2.0 mL organic solvent for a whole run,has been demonstrated to be an efficient way for screening and quantitative analysis of trace-level PAH-derivatives in soil samples. 展开更多
关键词 Ultra-high performance supercritical fluid chromatography Derivatives of polycyclic aromatic hydrocarbons Supercritical fluid extraction Fast separation Pollutant screening Quantitative analysis
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Optimization of conditions for supercritical fluid extraction of flavonoids from hops (Humulus lupulus L.) 被引量:4
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作者 何国庆 熊皓平 +3 位作者 陈启和 阮晖 王肇悦 TRAORé Lonseny 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第10期999-1004,共6页
Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO2 extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of... Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO2 extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at 50 °C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield fla- vonoids (7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid in hops. 展开更多
关键词 Carbon dioxide Carbon disulfide ETHANOL Food processing Medicine OPTIMIZATION Pressure Solvents Temperature
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Kinetics of Extraction of <i>β</i>-Carotene from Tray Dried Carrots by Using Supercritical Fluid Extraction Technique 被引量:1
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作者 Kamalpreet Kaur Uma Shanker Shivhare +1 位作者 Santanu Basu G. S. Vijaya Raghavan 《Food and Nutrition Sciences》 2012年第5期591-595,共5页
β-carotene acts as an antioxidant and is receiving growing interest due to its ability as protecting agent against heart diseases, cancer and strengthening effect on red blood cells. The main aim of this work was to ... β-carotene acts as an antioxidant and is receiving growing interest due to its ability as protecting agent against heart diseases, cancer and strengthening effect on red blood cells. The main aim of this work was to study the kinetics of the supercritical fluid extraction of β-carotene from tray dried carrots at 40℃, 50℃ and 55℃ and 30, 35 and 40 MPa at SC-CO2 flow rate of 2.0 L/min for extraction time of up to 6 h. It was observed that the concentration of β-carotene in the extract increased with pressure, temperature and extraction time. The results indicated that yield was found to be maximum at 45℃ and 35 MPa at 2 L/min SC-CO2 flow rate. Concentration of β-carotene in the extract increased with SC-CO2 flow rate. Weibull distribution model described adequately the kinetics of extraction of β-carotene from carrots. 展开更多
关键词 β-Carotene KINETICS Supercritical fluid extractION CARROTS Weibull Distribution Model
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Study on a New Method of Extraction of Metal Ions from SolidMatrices by Supercritical Fluid
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作者 Zhao Jie CUI Jun Cheng LIU +2 位作者 Lain Cun GAO Ying Qin WEI Jun Zeng ZHANG(Department of Environmental Engineering, Shandong University. Jinan 250100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第6期525-528,共4页
8-Hydroxyquinoline, methanol and Triton-100 were first used together in the extraction of metal ions by supercritical CO2. In the new system, the effects of pressure, temperature and the volume of CO2 on the efficienc... 8-Hydroxyquinoline, methanol and Triton-100 were first used together in the extraction of metal ions by supercritical CO2. In the new system, the effects of pressure, temperature and the volume of CO2 on the efficiency of supercritical fluid extraction (SFE) were systematically investigated. The recovery under the optimum condition was only 11.38%, but if suitable concentration of methanol (v/v=5%) was added to the supercritical CO2, the recovery was increased significantly (83.60%, RSD=4.37%, n=5). In order to further enhance the recovery Triton X-100 was added to the samples, and the results were satisfactory (96.62%, RSD=2.85%, n=5). 展开更多
关键词 supercritical fluid extraction chelating agent MODIFIER SURFACTANT metal ions solid matrices
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Optimization of Supercritical Fluid Extraction of Tea Flower Polysaccharides by Using Response Surface Method 被引量:1
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作者 Xing-Hai Zhang Fei Que +2 位作者 Jin-Wei Xu Pei-Li Yu You-Ying Tu 《茶叶》 2013年第4期442-451,共10页
Polysaccharide production from tea flower(TFPS) was carried out using supercritical fluid extraction(SFE).Response surface methodology(RSM),based on a five level,four variable small central composite design,was employ... Polysaccharide production from tea flower(TFPS) was carried out using supercritical fluid extraction(SFE).Response surface methodology(RSM),based on a five level,four variable small central composite design,was employed to obtain the best possible combination of extraction time,pressure,temperature and ethanol content of modifier for maximum production.The optimum conditions were as follows:extraction time of 170 min,pressure of45 MPa,temperature of 75 ℃,and 50% aqueous ethanol solution as modifier.Under these conditions,the experimental yield was 6.56 ± 0.37%,which was similar to the value predicted by the model.Monosaccharide composition of TFPS was fucose,rhamnose,arabinose,xylose,galactose,glucose,mannose,fructose,ribose,galacturonic acid and glucuronic acid in a molar percent of 31.69,0.21,0.49,1.29,35.82,0.97,1.63,18.34,7.88,1.06 and 0.63.Compared to other extraction methods,SFE could achieve higher yield and gain more types of monosaccharide. 展开更多
关键词 超临界流体萃取 茶多糖 响应曲面法 葡萄糖醛酸 半乳糖醛酸 优化 花卉 中心复合设计
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EFFECTS OF ENTRAINERS ON THE PHASE EQUILIBRIUM OF SUPERCRITICAL FLUID EXTRACTION PROCESS
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作者 张建君 朱美文 +1 位作者 于恩平 张泽廷 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1993年第4期54-61,共8页
A flow apparatus was set up for measuring the solubility of a solid solute in a supercritical fluid withthe presence of a small amount of entrainer.The solubilities of biphenyl,diphenylamine and benzoic acid insupercr... A flow apparatus was set up for measuring the solubility of a solid solute in a supercritical fluid withthe presence of a small amount of entrainer.The solubilities of biphenyl,diphenylamine and benzoic acid insupercritical carbon dioxide with one of the selected entrainers which were ethanol,acetone and n-hexanerespectively,were obtained in the pressure range of 10—32 MPa and the temperature range of 308—318K.Asolvolytic association theory has been proposed to explain the mechanism of entrainer effect,and theexperimental results were reasonably analysed.According to the solvolytic association theory,the association equa-tion of state was adopted to correlate the experimental data with good accuracy. 展开更多
关键词 ENTRAINER phase EQUILIBRIUM SUPERCRITICAL fluid extractION SOLUBILITY
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Quality of Canola Oil Obtained by Conventional and Supercritical Fluid Extraction
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作者 Rabie Khattab Curtis Rempel +1 位作者 Miyoung Suh Usha Thiyam 《American Journal of Analytical Chemistry》 2012年第12期966-976,共11页
Quality of canola oil obtained by the supercritical fluid extraction (SFE), using CO2 with ethanol as a co-solvent, was evaluated and compared to that of the conventionally-obtained oils using either n-hexane or chlor... Quality of canola oil obtained by the supercritical fluid extraction (SFE), using CO2 with ethanol as a co-solvent, was evaluated and compared to that of the conventionally-obtained oils using either n-hexane or chloroform methanol mixture. Physical characteristics, chemical properties, fatty acid composition and phenolic profile of oils were investigated. The SFE oil showed significantly lower melting point, peroxide value (PV) and higher free fatty acids (FFAs) and iodine value (IV) than the n-hexane-extracted one. There were no significant differences in the fatty acid composition of different oils. The SFE oil showed significantly higher phenolic content (35.91, 10.15, 3.16, 0.32 and47.48mg/g of sinapic acid, sinapine, sinapoyl glucose, canolol and total phenolics) as compared to 0.08, 0.70, 0.88, 0.45 and0.71mg/g, respectively in the n-hexane-extracted oil. These results indicate the superiority of SFE and advocate its use for the extraction of highly stable and functional canola oil for further health and nutraceutical uses. The present results have an industrial and technological relevance as SFE could be competitive with the traditional extraction techniques providing an environmental approach and enhancing the obtained oil quality and stability. After recovery of the initial installation costs, SFE could be more economic than conventional extraction. However, further economical studies are needed to validate this last conclusion. 展开更多
关键词 CANOLA OIL QUALITY SUPERCRITICAL fluid extraction
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Influence of Modifiers, Extractants, and Trappers on Lipid Composition with Liquids in Standard State Extraction, Supercritical Fluid Extraction and Trapping by Supercritical Fluid Extraction, Part II
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作者 Ilia Brondz 《International Journal of Analytical Mass Spectrometry and Chromatography》 2017年第4期87-95,共9页
Modifiers have a broad array of influences on extraction with liquids in standard state, supercritical fluid extraction (SFE), trapping by SFE and supercritical fluid chromatography (SFC). They can significantly chang... Modifiers have a broad array of influences on extraction with liquids in standard state, supercritical fluid extraction (SFE), trapping by SFE and supercritical fluid chromatography (SFC). They can significantly change the qualitative and quantitative results. Quantitative and qualitative results can be influenced by different extractants and modifiers in different ways as it was shown by Brondz et al. at 2007 in “The real nature of the indole alkaloids in Cortinarius infractus: Evaluation of artifact formation through solvent extraction method development”, J. Chromatography A, 1148, 1-7. The choice of correct extractant, modifier, and trapper to the bulk mobile phase for supercritical fluids (SFs) or for liquids in subcritical or in the liquids in standard state is a challenge in any extraction procedure. This is the second paper in a sequence that describes the influence of extractants and modifiers on the performance of SFs and results of extraction with liquids in standard state and SFE. Here, attention is given to possible mistakes in qualitative and quantitative results by poor understanding of the influence of extractants, modifiers, and trappers on extraction and trapping process by a careless choice of extractant, modifier, and trapper for extraction with liquids in standard state and SFE. The SF chosen for discussion in the paper is CO2. However, similar effects can be observed with use of other SFs and fluids in subcritical and standard states. In this paper, the discussion of lipids, fatty and carboxylic acids have been chosen as target analytes for extraction, trapping and analysis. Some examples from extraction with liquids in the standard state and trapping in the supercritical state (collection) have been furnished with the wrong extractant, modifier, or trapper which is presented for illustration of inappropriate choice of extractants, modifiers, and trappers. 展开更多
关键词 MODIFIERS extractANTS Trappers SUPERCRITICAL fluid Chromatography SUPERCRITICAL fluid extractION extractION with Liquids in Standard State Lipids FATTY ACIDS Carboxylic ACIDS extractION of FATTY and Carboxylic ACIDS
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Separation of Molybdenum Isotopes at Supercritical Fluid Extraction with Carbon Dioxide in a Vertical Gradient Field of Temperatures
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作者 Boris Viktorovich Borts Stella Fedorovna Skoromnaya Viktor Ivanovich Tkachenко 《Open Journal of Metal》 2020年第1期1-15,共15页
Separation of molybdenum isotope complexes by supercritical fluid extraction (SFE) with carbon dioxide was studied experimentally. The extraction of molybdenum isotope complexes was carried out in the updated extracti... Separation of molybdenum isotope complexes by supercritical fluid extraction (SFE) with carbon dioxide was studied experimentally. The extraction of molybdenum isotope complexes was carried out in the updated extraction chamber (reactor) of the SFE-U installation, which provided an initial pressure of P ≤ 20 MPa at constant temperatures of the upper T1 = 35&deg;C and bottom T2 = 45&deg;C flanges. The device, through which the eluent was discharged, involved a set of four thin tubes of different lengths located inside the reactor. The axes of the tubes and the reactor are parallel and the tubes are equally spaced circumferentially inside the reactor. The extract was removed from each tube through channels isolated from each other and located in the bottom flange with cylindrical expansion, in which several layers of filter paper were placed. After passing through the filters the extract entered a restrictor designed to remove the eluent from the reactor. The initial pressure of carbon dioxide and the holding time of the extract were specified in the experiments. The level of the eluent sampling was set by the lengths of the tubes depending on the reactor height. A method of producing molybdenum complexes was described. It was experimentally shown that at an initial pressure of 20 MPa and a given holding time a difference from the natural content of Mo isotopes for given heights of extract sampling depending on the reactor height was observed in extracts removed through filters. The ranges of deviation of the content of molybdenum isotopes in extracts from natural one were determined. 展开更多
关键词 Carbon Dioxide SUPERCRITICAL fluidS extraction MOLYBDENUM ISOTOPES SEPARATION
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Development and Validation of Extraction Method for the Determination of UC781 in Cervicovaginal Fluid
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作者 Naser L. Rezk Zhiqing Qiao Majed Jeriasy 《American Journal of Analytical Chemistry》 2013年第12期707-714,共8页
Liquid chromatography plays the important and critical role in the field of clinical pharmacology of evaluating drugs in biological matrices. Studying antiretroviral drugs in the female genital tract has important imp... Liquid chromatography plays the important and critical role in the field of clinical pharmacology of evaluating drugs in biological matrices. Studying antiretroviral drugs in the female genital tract has important implications for using drugs as a vaginal microbicide for prevention of HIV-1 sexual transmission. Accurate measurement of drug levels is extremely important in optimizing drug concentration in gel formulation. Extracting drugs from small volumes of viscous, proteinaceous substances like cervicovaginal fluid (CVF) is a practically challenging process. The proposed method was designed to introduce procedure for sample collection and drug extraction procedure for CVF matrix before the chromatographic separation. Based on this extraction method, we validated a reverse phase high performance liquid chromatography with electrospray ionization mass spectrometry assay in order to quantify UC781 in female genital tract compartment. The LC-MS method was validated based on a novel extraction technique which proved to be efficient in reducing analyte degradation with an average extraction efficiency of 72%. This method is accurate, demonstrating an average accuracy over three QC (n = 30) concentrations ranging from 99.9% to 106.1%. Average precision within-day and between-day ranged from 3.1% to 10.2% and 5.1% to 6.4%, respectively. We demonstrated that the analyte was able to maintain its stability under various conditions using this extraction method. The sample preparation, extraction, and the powerful liquid chromatography and mass spectrometry can readily be applied for accurate quantification of similar drugs in CVF. 展开更多
关键词 HIV-Prevention Cervicovaginal fluid extraction LC-MS Nonnucleoside REVERSE Transcriptase Inhibitor
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