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Essential oil components were extracted from lavandin (Lavandula hybrida) flowers using pressurized fluid extraction. A central composite design was used to optimize the effective extraction variables. The chemical composition of extracted samples was analyzed by a gas chromatograph-flame ionization detector column. For achieving 100% extraction yield, the temperature, pressure, extraction time, and the solvent flow rate were adjusted at 90.6°C, 63 bar, 30.4 min, and 0.2 mL/min, respectively. The results showed that pressurized fluid extraction is a practical technique for separation of constituents such as 1,8-cineole (8.1%), linalool (34.1%), linalyl acetate (30.5%), and camphor (7.3%) from lavandin to be applied in the food, fragrance, pharmaceutical, and natural biocides industries.  相似文献   

3.
超临界萃取川芎精油的GC-MS分析   总被引:6,自引:0,他引:6  
不同压力和温度条件下超临界萃取所得川芎精油的收率不同,通过气相色谱-质谱联用对精油的挥发性成分进行分析,结果表明不同条件下超临界萃取所得川芎精油的主要挥发性成分相似,但其质量分数有一些差别.  相似文献   

4.
《Comptes Rendus Chimie》2014,17(3):284-292
The aim of this study is to compare three oil extraction methods and to evaluate their efficiency for producing an oil rich in polyphenols. The three extraction methods are screw pressing, extraction by supercritical CO2 percolation and the combination of these two processes (Gas-Assisted Mechanical Expression: GAME). Screw pressing is the most efficient process for producing grape seed oil with a high yield, but supercritical CO2 process permits an increase of polyphenol co-extraction with oil. The GAME process allows extraction of more polyphenols than screw pressing and constitutes an interesting process considering oil yield.  相似文献   

5.
报道了用正交实验法研究超临界萃取淫羊藿挥发性成分的条件;结果显示最佳萃取条件为萃取压力30 MPa,萃取温度40℃,萃取时间1 h。按对结果影响大小依次排列为:萃取压力→萃取温度→萃取时间,在最佳条件下萃取挥发油,收率为2.7%;并用气相色谱-质谱联用技术分析了淫羊藿挥发油的化学成分,从中确认出43种化学成分,用峰面积归一化法通过化学工作站数据处理系统得出各化学成分在挥发油中的质量分数;其中主要成分为薄荷醇、1,2-二甲氧基-4-(2-丙烯基)-苯、5-(1-丙烯基)-1,3-苯并间二氧杂环戊烯、3,5-二甲氧基-甲苯、冰片、十五(碳)烷、1,2,3-三甲氧基-5-甲苯、外-葑醇、2,6,6-三甲基-2,4-环庚二烯-1-酮、2-莰酮等。  相似文献   

6.
Supercritical fluid extraction in plant essential and volatile oil analysis   总被引:9,自引:0,他引:9  
The use of supercritical fluids, especially carbon dioxide, in the extraction of plant volatile components has increased during two last decades due to the expected advantages of the supercritical extraction process. Supercritical fluid extraction (SFE) is a rapid, selective and convenient method for sample preparation prior to the analysis of compounds in the volatile product of plant matrices. Also, SFE is a simple, inexpensive, fast, effective and virtually solvent-free sample pretreatment technique. This review provides a detailed and updated discussion of the developments, modes and applications of SFE in the isolation of essential oils from plant matrices. SFE is usually performed with pure or modified carbon dioxide, which facilitates off-line collection of extracts and on-line coupling with other analytical methods such as gas, liquid and supercritical fluid chromatography. In this review, we showed that a number of factors influence extraction yields, these being solubility of the solute in the fluid, diffusion through the matrix and collection process. Finally, SFE has been compared with conventional extraction methods in terms of selectivity, rapidity, cleanliness and possibility of manipulating the composition of the extract.  相似文献   

7.
建立西黄丸中挥发油成分乙酸辛酯的含量测定方法,为西黄丸的质控标准提供依据。方法:超临界CO2萃取西黄丸中挥发油成分,采用气相色谱法测定乙酸辛酯含量;研究压力、温度、时间和粒度因素对挥发油得率与乙酸辛酯含量的影响,并进行了化学计量学分析。采用GC-MS分析了适宜条件的挥发油的成分。综合考虑挥发油得率和乙酸辛酯含量双指标,确定的西黄丸挥发油萃取条件为:粉碎粒度为80目,萃取压力为25 MPa,温度为40℃,时间为2 h。在此条件下,挥发油得率达到7.76%,乙酸辛酯含量达到0.72 mg·g-1。通过指纹图谱、主成分分析(PCA)、正交偏最小二乘判别分析(OPLS-DA)化学计量学分析可知,不同萃取条件对所提取的挥发油物质组分及其含量没有显著性差异。GC-MS鉴定出的主要成分有(1S-endo)-2-甲基-3-亚甲基-2-(4-甲基-3--3-戊烯基)-二环[2.2.1庚烷、10α-羟基日本刺参萜、(±)-麝香酮、4-亚甲基-2,8,8-三甲基-2-乙烯基-双环[5.2.0]壬烷和2-甲基-4-(2,6,6-三甲基-1-环己烯-1-基)丁醛。结论:西黄丸挥发油成分适宜萃取条件,及建立的乙酸辛酯含量测定方法准确、可靠,为有效控制西黄丸质量,完善其质量标准及进一步的药效成分研究提供了科学依据。  相似文献   

8.
Supercritical fluid extraction (SFE), which has received much interest in its use and further development for industrial applications, is a method that offers some advantages over conventional methods, especially for the palm oil industry. SC-CO? refers to supercritical fluid extraction (SFE) that uses carbon dioxide (CO?) as a solvent which is a nontoxic, inexpensive, nonflammable, and nonpolluting supercritical fluid solvent for the extraction of natural products. Almost 100% oil can be extracted and it is regarded as safe, with organic solvent-free extracts having superior organoleptic profiles. The palm oil industry is one of the major industries in Malaysia that provides a major contribution to the national income. Malaysia is the second largest palm oil and palm kernel oil producer in the World. This paper reviews advances in applications of supercritical carbon dioxide (SC-CO?) extraction of oils from natural sources, in particular palm oil, minor constituents in palm oil, producing fractionated, refined, bleached, and deodorized palm oil, palm kernel oil and purified fatty acid fractions commendable for downstream uses as in toiletries and confectionaries.  相似文献   

9.
Supercritical fluid extraction (SFE) exploits the solvation power of fluids at temperatures and pressures close to their critical point. Use of SFE with supercritical CO2 is reported for the extraction of caffeine and quinine from various plant materials and of morphine from serum. Results are compared with those obtained by extractions with subcritical methanol and tetrahydrofuran, normal organic Soxhlet extractions and solid-phase extraction.  相似文献   

10.
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Improved supercritical fluid extraction of sulphonamides   总被引:4,自引:0,他引:4  
Summary Different ways used for enhancing the yield of sulphonamides leached from solid supports are reported. Supercritical CO2 and methanol-modified CO2 were used as extractants of the target analytes and the impregnation of the solid sample with buffer, derivatization of the analytes and ion-pair formation were assessed. Only the sulphonamide/tetramethyl-ammonium ion-pairs are quantitatively extracted from the solid supports using pure supercritical CO2, while the other modifications and the presence of a cosolvent lead to recoveries lower than 30% for most of the analytes. Individual separation/quantitation of the analytes was performed off-line using a liquid chromatograph.  相似文献   

12.
In this paper, the volatile compounds of Schisandra chinensis obtained by different extraction techniques including supercritical fluid extraction (SFE), steam distillation (SD), Soxhlet extraction (SE) and ultrasound-assisted extraction (UAE) were investigated for the first time. The sample preparation procedure for GC-MS analysis of the volatile compounds was optimized and then 37, 45, 27 and 37 compounds were identified in the samples obtained by SFE, SD, SE and UAE methods, respectively. As the therapeutic effect of the traditional Chinese medicine is usually based on multifarious essential components or the combination of them instead of only one component, the volatile compounds were compared in groups with the extracts by SE, SD and UAE. This would be more reasonable to evaluate the effects of an alternative technique to extracting multifarious essential components. Among the identified components in the SFE extract, 32 compounds were the same as that by three conventional methods, accounting for 90.5% of the volatile compounds identified. However, as the volatile compounds were classed into groups, it was easy to see that the Schisandra chinensis oil extracted by SFE was made up largely of aromatics and sesquiterpenoids (52.1 and 27.6%, respectively), with less amounts of monoterpenoids and other compounds, distinguishing SFE from the conventional extractions.  相似文献   

13.
14.
Collection in analytical-scale supercritical fluid extraction   总被引:4,自引:0,他引:4  
This review is a comprehensive summary of available collection techniques in supercritical fluid extraction (SFE), with emphasis on which parameters are especially important for a successful analyte collection. Environmental, biological and agricultural applications, including several types of sample matrices and analyte groups, are discussed with respect to choice of collection mode and optimization of collection conditions. This review also includes discussions about collection when a modifier is used or when the sample contains large amounts of fat or water, as well as possibilities to achieve enhanced selectivity.  相似文献   

15.
 For the determination of 16 PAHs in soils and sediment samples by GC/FID and GC/MS, the dynamic off-line supercritical fluid extraction with both pure and modified carbon dioxide has been evaluated. The optimisation of extraction parameters was performed for four individual groups of PAHs according to their number of aromatic rings (2–3 rings, 4 rings, 5 rings and 6 rings) by varying pressure (200–510 bar), temperature (50–150 °C), extraction fluid volume (10–50 ml), and the methanol modifier concentration (0–10%). Using a five level spherical factorial experimental design the number of experiments required for optimisation was 45. In spiked soil samples extraction efficiencies of 80–100% were achieved for the individual groups of PAHs. At the optimal set of conditions 10–30% lower recoveries of PAHs were obtained for the standard reference material NIST SRM 1941a (marine sediment). The largest differences between extraction recoveries of native and spiked PAHs occurred at high molecular weight PAHs. Using SFE efficiency data for the standard reference material, cluster analysis proved that dividing the 16 PAHs into four groups according to their number of aromatic rings was appropriate and correct. Received: 2 February 1996/Revised: 26 November 1996/Accepted: 30 November 1996  相似文献   

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Different from the west medicine, the therapeutic effect of the traditional Chinese medicine is usually based on multifarious essential components or the combination of them instead of only one component. In this paper, a novel supercritical fluid extraction (SFE) method has been developed for extracting tanshinones (dihydrotanshinone I, cryptotanshinone, tanshinone I, and tanshinone II(A)) from Danshen, the dried root of Salvia miltiorrhiza. Various experimental conditions were investigated to optimize the SFE. Under the appropriate conditions, extracting at 40 MPa, and 50 degrees C and with CO(2) flow rate of 25 L/h for 1 h, SFE can achieve a better yield as well as the recoveries of the tanshinones than the conventional extraction using methanol. Moreover, the target compounds were analyzed by HPLC with a C(18) RP column by gradient elution using ACN and water as mobile phase at a flow rate of 1.0 mL/min and with UV detection at 270 nm. Four calibration equations were then established and good linear relationships were shown (r(2) >0.999) in the investigated concentration range. The recoveries, measured at three concentration levels, varied from 97.2 to 103.8%. The method provided in this article could be applied as an improved quality control method for Danshen products.  相似文献   

18.
Supercritical fluid extraction (SFE) was used to extract saikosaponins a, c and d from the root of Bupleurum falcatum. An orthogonal array design L9(3)4 was employed as a chemometric method for the optimization of the SFE conditions. The effects of four factors including pressure (30–40 MPa), temperature (40–50°C), ethanol concentration (60–100%) and time (2.5–3.5 h) on the yields of saikosaponins were investigated by a preparative SFE system in the SFE mode. Under the optimized conditions, namely 35 MPa of pressure, 45°C of temperature, 80% of ethanol concentration and 3.0 h of time, the yields of saikosaponin c, saikosaponin a, saikosaponin d, total saikosaponins and SFE extract were 0.16, 0.12, 0.96, 1.24 and 16.48 mg/g, respectively. Determinations of the saikosaponins were performed by HPLC.  相似文献   

19.
Supercritical fluid extraction (SFE) is combined with supercritical fluid chromatography (SFC) in an analytical mode to develop a system for fractionating and enriching high value ferulate-phytosterol esters (FPE) contained in corn bran oil. Corn bran is initially extracted with neat supercritical carbon dioxide (SC-CO2) at various pressures (13.8, 34.5, and 69 MPa) and temperatures (40, 60, and 80 degrees C) to see if the FPE can be enriched in the extracts. These initial studies show the greatest percentage of FPE could be extracted under two sets of conditions: 69 MPa at 80 degrees C and 34.5 MPa at 40 degrees C. Both sets of parameters yield an extract containing approximately 1.25% FPE. A stock supply of corn bran oil is then produced by scaled-up SFE at 34.5 MPa and 40 degrees C for subsequent chromatographic fractionation. The SFE-obtained corn bran oil is then applied to the head of a minichromatographic column containing an amino-propyl sorbent. SFC is than commenced using neat SC-CO2 at 69 MPa and 80 degrees C to remove the majority of the triglyceride-based oil. Pressure and temperature are then lowered to 34.5 MPa and 40 degrees C, respectively, and ethanol is added as a modifier. The modifier is added in an increasing stepwise gradient program, and fractions are collected at equal volume intervals. The resultant fractions are analyzed by analytical high-performance liquid chromatography with evaporative light-scattering detection and show that FPE could be enriched to a 14.5% (w) level.  相似文献   

20.
采用超声波强化超临界CO2萃取樟树叶精油,并采用正交实验对萃取工艺进行了优化.研究结果表明:当萃取压力为16MPa、温度为50℃、时间为80min、CO2流量为16kg/h、超声波功率为240W、超声波频率为20KHz时,能获得比较好的效果,精油的平均提取率可达1.92%.GC-MS的分析结果表明:樟树叶精油中樟脑+β...  相似文献   

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