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超临界CO2流体萃取法与水蒸气蒸馏法提取荆芥穗挥发油化学成分的研究 总被引:6,自引:0,他引:6
采用超临界CO2萃取法(SFE)与水蒸气蒸馏法(SD)从荆芥穗中提取挥发油。采用SE-54毛细管柱进行分析,用气相色谱-质谱法对挥发油中各种化学成分进行鉴定,用归一化法测定各组分的含量。色谱条件:SE-54毛细管柱 (30 m×0.25 mm i.d.,0.25 μm),柱温50 ℃(3 min)5 ℃/min180 ℃(2 min)10 ℃/min260 ℃(50 min);分流进样,分流比1∶50;进样口温度280 ℃。在采用超临界CO2萃取法提取的挥发油中共鉴定出54种成分,其主要成分为长叶薄荷酮、薄荷酮、亚油酸氯化物等;在水蒸气蒸馏法提取的挥发油中共鉴定出39种成分,其主要成分为长叶薄荷酮、薄荷酮、柠檬烯等。超临界法较水蒸气法更加稳定可靠,重现性好,适用于中药挥发油的化学成分分析。 相似文献
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设计了一种简易同时蒸馏萃取(SSDE)装置并用于八角茴香挥发油提取及其气相色谱-质谱法(GC-MS)分析。 该装置由圆底烧瓶、恒压滴液漏斗和回流冷凝管构成。 通过对八角茴香挥发油组分的GC-MS分析,比较SSDE法和水蒸汽蒸馏提取法(HD)提取植物源挥发油的效果。 结果表明,SSDE法所得挥发油相对含量在0.1%以上的19种化合物占挥发油总量的98.84%(相对标准偏差(RSD)(n=3)均不大于5.59%,其中RSD﹤5%的17种化合物占鉴定组分89.5%。SSDE法和HD法挥发油平均收率分别为7.30%(RSD=2.37%(n=5))和6.67%(RSD=5.26%(n=5))。 SSDE法简便、快速,适用于八角茴香挥发油的提取。 相似文献
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茵陈挥发油的超临界CO2萃取法与水蒸气蒸馏法提取的比较 总被引:10,自引:0,他引:10
采用超临界CO2萃取法与水蒸气蒸馏法从菌陈中提取挥发油,用GC-MS法测定其化学成分和相对含量,对两种提取方法所得的挥发油进行比较,水蒸气蒸馏法提取菌陈挥发油的产率为0.03%(w),主要成分为匙叶桉油烯醇、吉玛烯D、反式-石竹烯、2,4-戊二炔苯、β-金石欢烯等;超临界CO2萃取法提取的产率为0.15%(w),主要成分为百里酚、β-红没药烯、2-异丙基-4-甲基-1-甲氧基苯、异百里酚、2-特丁基-4-(2,4,4-三甲基戊基)苯酚、β-杜松烯等。 相似文献
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The application of supercritical fluid extraction (SFE) to prepare samples in analytical laboratories is a rapidly expanding area. In comparison with traditional extraction methods, SFE have many advantages, such as short time, low consumption, low pollution, high precision and high selectivity. SFE of analytes from aqueous samples has received little attention as compared with the SFE of solid samples. Since it is difficult to prevent the coextraction of water with the contaminants, which would result in the plugging of the restrictor, generally, SFE is combined with solid phase adsorption (SPA) in treating aqueous samples. 相似文献
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Four sampling techniques, solid-phase microextraction (SPME), supercritical fluid extraction (SFE), steam distillation (SD), and solvent extraction (SE), were compared for the analysis of volatile constituents from a traditional Chinese medicine (TCM) of the dried ripe fruit of Fructus Amomi (Sha Ren). A total of 38 compounds were identified by gas chromatography/mass spectrometry. Different SFE and SPME parameters (modifier content, extraction pressure, and temperature for SFE and fibers, extraction temperature, and time for SPME) were studied. The results by SFE and SPME were compared with those obtained by conventional SD and SE methods. The results showed that SFE and SPME are better sample preparation techniques than SD and SE. Due to SFE's requirement for expensive specialized instrumentation, the simplicity, low cost, and speed of SPME make it a more appropriate technique for extraction of volatile constituents in TCMs. 相似文献
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This paper reports on the first use of supercritical fluid extraction (SFE) of polychlorinated biphenyls (PCBs) from pine needles. Supercritical carbon dioxide was used as extraction fluid, and exhibited good extraction efficiencies and recoveries (>90%). GC-MS (selected ion monitoring mode) achieved both accurate identification and quantification of the PCBs. Compared with traditional time consuming multi-step sample preparation methods, SFE with carbon dioxide is easier to perform, and is a feasible alternative extraction procedure for the monitoring of PCBs in pine needle samples. 相似文献
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A method consisting of automated supercritical fluid extraction (SFE) with simultaneous cleanup by a solid-phase trap was developed for fast analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in soil. SFE was optimised to replace conventional liquid-based methods in routine analyses of PCDD/PCDFs in sawmill soil contaminated by a chlorophenol formulation. PCDD/PCDFs were quantitatively extracted in 60 min using CO2 at 400 atm and 100 degrees C without a modifier. A trap containing a small amount of activated carbon mixed with Celite efficiently collected PCDD/PCDFs after SFE. After SFE co-extracted impurities were eluted out from the trap with 4 ml of hexane and PCDD/PCDFs were eluted with 10 ml of toluene. The concentrations and TCDD-equivalent of PCDD/PCDFs corresponded to the results of traditional solvent extraction method (Soxhlet) in six sawmill soils tested. The performance of the trap was maintained over a long period of time (nearly 100 extractions). 相似文献
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Stefano Polesello Fabio Lovati Anna Rizzolo Constanza Rovida 《Journal of separation science》1993,16(9):555-559
To improve the aroma characterization of various strawberry cultivars, we tested supercritical fluid extraction (SFE) to determine its suitability for the extraction of aroma compounds from fresh fruit, comparing SFE results with traditional solvent extraction with dichloromethane. Using SFE it was possible to recover the majority of the aroma compounds which can be also found in the solvent extract; patterns related to variety and degree of maturation were preserved. Our results showed, however, that SFE is more selective and was able to recover the ‘character impact’ compound of wild strawberry. Our findings from the odor analysis of furaneol standard emphasize the importance of using a more selective extraction procedure, and always combining instrumental detection with sensory analysis. 相似文献
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Two different relatively simple, commercially available supercritical fluid extractors (SFE), Leco and Foss-Tecator, were tested for the determination of total fat content in meat and meat products. The fatty acid composition in meat and meat products was also determined after the Foss-Tecator extraction in an aliquot of the extract. Total fat was determined by weighing after the different extraction procedures and the fatty acid composition by gas chromatography after hydrolysis and methylation of the extract. The results for total fat content agreed well with results from a standard method of Schmid, Bondzynski, and Ratzlaff, which uses conventional solvent extraction. Fatty acid composition was compared with the Bligh and Dyer extraction, and showed good agreement. The average relative difference between SFE and Bligh and Dyer of all fatty acids in the sample was <3% for acids exceeding 0.5% of total fatty acid amount. The advantages of SFE over traditional methods are a much lower consumption of hazardous organic solvents and shorter extraction times. To obtain quantitative recoveries by SFE, ethanol was added to the extraction cells before extraction. 相似文献
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GC-MS of volatile components of Schisandra chinensis obtained by supercritical fluid and conventional extraction 总被引:1,自引:0,他引:1
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
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The efficiencies of extraction of vapor-deposited pyrene from a high-carbon coal stack ash by Soxhlet extraction with methanol, ultrasonic extraction with toluene, acid pretreatment and subsequent ultrasonic extraction with toluene, batch extraction with toluene, and supercritical fluid extraction (SFE) are compared. SFE using CO(2) or isobutane yielded extraction recoveries virtually identical with those obtained using ultrasonic or Soxhlet extraction processes. Collection of the SFE extract was performed by expansion into a solvent or onto the head of a gas chromatography (GC) column. No loss of extracted pyrene was observed upon collection of methanol-modified CO(2) SFE by expansion into methanol. Also, no loss of pure CO(2) SFE extract was observed upon collection on the head of a GC column. However, use of a methanol or toluene modifier for CO(2) SFE directly coupled to GC effected complete loss of extracted pyrene. 相似文献
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The use of supercritical fluid extraction (SFE) is growing, with an expanding range of applications in many different fields as a consequence of its advantages compared with traditional extraction methods. In order to develop an analytical method to determine dibutyl phthalate (DBP) and dioctyl phthalate (DOP) traces (<20 ppm) in flexible poly(vinyl chloride) (PVC) formulations, a maximum efficiency in the extractive process and an adequate separative system are needed to avoid interferences between these two plasticizers and other additives that could be present at high concentrations in flexible PVC formulations. In order to determine the optimum SFE conditions, the extraction time, temperature and pressure were controlled. The separation and quantitation of individual components in the PVC extracts were carried out off-line by using a semicapillary column in gas chromatography (GC). Samples with different DOP content (41.18%, 33.33% and 23.08%) and DBP content (41.18%), as well as samples with both plasticizers (20.59% DOP and 20.59% DBP) were prepared. Some other samples were also prepared to study detection limits for these two PVC additives. Recoveries and reproducibilities were studied in every sample. Finally, this method was compared with Soxhlet liquid extraction. Determination by gravimetric analysis of the total extracted material was found to be particularly suitable for PVC. This study demonstrates the potential of SFE to shorten extraction times with similar or even better extraction efficiencies compared with traditional liquid methods. 相似文献