Countercurrent supercritical fluid extraction and fractionation of alcoholic beverages

A procedure for the recovery of aromatic extracts from distilled alcoholic beverages by means of a countercurrent supercritical fluid extraction (CC-SFE) on a pilot plant scale is studied. The beverage is directly in contact with the carbon dioxide current in a packed column, and the extracts are recovered in two different fractionation cells, where the depressurization occurs. The proposed method allows the selective extraction of aromatic components of the brandy flavor, rendering a high-value concentrated extract and a colored residue without brandy aroma. The content in ethanol of the aromatic extract can be modified by tuning the extraction/fractionation conditions, rendering from 15 to 95% recovery. The effect of the main variables, including extraction pressure and quality of extracting CO(2), has been tested.     

Functional properties of spice extracts obtained via supercritical fluid extraction

In the present study the antioxidant, anticancer, and antimycobacterial activities of extracts from ginger (Zingiber officinale Roscoe), rosemary (Rosmarinus officinalis L.), and turmeric (Curcuma longa L.) were evaluated. The extracts were obtained using supercritical CO(2) with and without ethanol and/or isopropyl alcohol as cosolvent. The extracts' antioxidant power was assessed using the reaction between beta-carotene and linolenic acid, the antimycobacterial activity against M. tuberculosis was measured by the MABA test, and their anticancer action was tested against nine human cancer ancestries: lung, breast, breast resistant, melanoma, colon, prostate, leukemia, and kidney. The rosemary extracts exhibited the strongest antioxidant and the lowest antimycobacterial activities. Turmeric extracts showed the greatest antimycobacterial activity. Ginger and turmeric extracts showed selective anticancer activities.     

Direct connection of supercritical fluid extraction and supercritical fluid chromatography as a rapid quantitative method for capsaicinoids in placentas of Capsicum.

The fruits of Capsicum annuum L. are used worldwide as chili peppers and in folk medicines. The pungent components of C. annuum, which are irritants, are called capsaicinoids (CAPS), and the most abundant components are capsaicin, dihydrocapsaicin, and nordihydrocapsaicin. To analyze CAPS in the placentas of Capsicum fruits rapidly and safely, we used a directly connected system of supercritical fluid extraction and supercritical fluid chromatography (SFE/SFC). As a column for SFE/SFC, only a silica-type column was found to be suitable. The CAPS contents in placentas of C. annuum cv. Jalapeno (hot type) and C. annuum cv. Shishitoh (less-hot type) determined by the SFE/SFC method agreed well with those in the range of 0-13.81 mg g(-1) fr. wt determined by the usual extraction-HPLC method. The SFE/SFC method has the advantages of no need for pretreatment and no (or minimal) need for organic solvents. We conclude that this method is useful as a rapid (20 min) and safe screening test for the pungency of various Capsicum fruits.     

裸大麦中生育三烯酚的超临界CO2流体萃取工艺

采用四元二次通用旋转设计研究了裸大麦中生育三烯酚的超临界CO2流体萃取工艺.结果表明:萃取温度对生育三烯酚提取率有显著影响,乙醇添加量和萃取时间对生育三烯酚提取率有极显著影响,而萃取压力对生育三烯酚提取率无显著影响,但萃取压力和乙醇添加量的交互项对生育三烯酚提取率有显著影响;在本实验条件下,生育三烯酚最佳超临界CO2萃取条件为:萃取温度51.8℃、萃取压力34.7 MPa、乙醇添加量9%、萃取时间120 min.     

Characterization of carrot root oil arising from supercritical fluid carbon dioxide extraction

Carrot root oil (SCO), obtained by supercritical fluid carbon dioxide (SC-CO2) extraction, was characterized and compared to a commercial carrot oil (MCO) and a virgin olive oil (VOO) (cv. Coratina). SCO showed much higher contents of carotenes, phenolics, waxes, phytosterols, and sesquiterpene and monoterpene volatiles. In SCO, the most prominent components present in the fully investigated analytical fractions (fatty acids, triglycerides, waxes, phytosterols, long-chain aliphatic alcohols, superior triterpene alcohols, and volatiles) were, respectively, linolenic acid, trilinolein, waxes C38, beta-sitosterol, campesterol and stigmasterol, 1-hexacosanol, 24-methylencycloartanol and cycloartenol, beta-caryophyllene, alpha-humulene, alpha-pinene, and sabinene. In VOO, the major constituents of the above analytical classes were, respectively, oleic acid, trilinolein, waxes C36, unsaturated volatile C6 aldehydes (trans-2-hexenal most markedly), and the same prominent sterols and superior alcohols found in SCO. In MCO, which also contained a proportion of unknown plant oil, several components showed magnitudes that were lower compared to SCO but higher with respect to VOO. The last had the aliphatic and triterpene alcohol concentration higher compared to that of both SCO and MCO. Several chemometric methods, applied to different analytical data sets, proved to be effective in grouping the three oil kinds.     

火力楠根超临界提取物对马尾松种子的化感效应研究

研究火力楠根超临界提取物对马尾松种子的化感效应结果表明,纯CO2萃取的火力楠根生化物质对马尾松种子绝对发芽率、绝对发芽势、胚根长、胚轴长、鲜物质量及干物质量有显著抑制作用;夹带剂与CO2混合萃取的火力楠根生化物质对马尾松种子绝对发芽率、胚轴长及鲜物质量、干物质量有不同程度促进作用,而对绝对发芽势、胚根长则有抑制作用。     

Fractional extraction of compounds from grape seeds by supercritical fluid extraction and analysis for antimicrobial and agrochemical activities

White grape seeds were subjected to sequential supercritical fluid extraction. By increasing the polarity of the supercritical fluid using methanol as a modifier of CO(2), it was possible to fractionate the extracted compounds. Two fractions were obtained; the first, which was obtained with pure CO(2), contained mainly fatty acids, aliphatic aldehydes, and sterols. The second fraction, obtained with methanol-modified CO(2), had phenolic compounds, mainly catechin, epicatechin, and gallic acid. The fractions were bioassayed. Antimicrobial activities were checked on human pathogens, and a high degree of activity was obtained with the lipophilic fraction. Agrochemical activities on phytopathogenic fungi and activities on the etiolated wheat coleoptile bioassay were also checked. The more polar fraction was active in the latter bioassay.     

Quantitative determination of allicin in garlic: supercritical fluid extraction and standard addition of alliin

A quantitative method is described for the determination of allicin (2-propene-1-sulfinothioic acid S-2-propenyl ester) in garlic, using standard additions of alliin (l-(+)-S-allylcysteine sulfoxide) in conjunction with supercritical fluid extraction (SFE) and high performance liquid chromatography analysis with UV-vis absorbance detection. Optimum CO(2)-SFE conditions provided 96% recovery for allicin with precision of 3% (RSD) for repeat samples. The incorporation of an internal standard (allyl phenyl sulfone) in the SFE step resulted in a modest improvement in recovery (99%) and precision (2% RSD). Standard additions of alliin were converted to allicin in situ by endogenous alliinase (l-(+)-S-alk(en)ylcysteine sulfoxide lyase, EC 4.4.1.4). Complete conversion of the spiked alliin to allicin was achieved by making additions after homogenization-induced conversion of the naturally occurring cysteine sulfoxides to thiosulfinates had taken place, thus eliminating the likelihood of competing reactions. Concentration values for allicin determined in samples of fresh garlic (Allium sativum L. and Allium ampeloprasum) and commercially available garlic powders (Allium sativum L.) by standard addition of alliin were found in all cases to be in statistical agreement (95% confidence interval) with values determined using a secondary allicin standard (concentration determined using published extinction coefficients). This method provides a convenient alternative for assessing the amount of allicin present in fresh and powdered garlic, as alliin is a far more stable and commercially prevalent compound than allicin and is thus more amenable for use as a standard for routine analysis.     

裸大麦中生育三烯酚的超临界CO2流体萃取工艺

采用四元二次通用旋转设计研究了裸大麦中生育三烯酚的超临界CO₂流体萃取工艺。结果表明：萃取温度对生育三烯酚提取率有显著影响,乙醇添加量和萃取时间对生育三烯酚提取率有极显著影响,而萃取压力对生育三烯酚提取率无显著影响,但萃取压力和乙醇添加量的交互项对生育三烯酚提取率有显著影响;在本实验条件下,生育三烯酚最佳超临界CO₂萃取条件为：萃取温度51.8 ℃、萃取压力34.7 MPa、乙醇添加量9%、萃取时间 120 min。     

Enhanced supercritical fluid carbon dioxide extraction of pesticides from foods using pelletized diatomaceous earth

Supercritical fluid carbon dioxide (SC-CO2), when used with an extraction enhancer, comprises a supercritical fluid extraction (SFE) system for extraction of pesticides and matrix components from fatty and nonfatty foods. After being mixed with the enhancer, samples ranging from 95% water to pure lipophilic oils can be extracted efficiently with SC-CO2. This extraction technique yields analyte recoveries in excess of 85% for over 30 types of pesticides at incurred levels ranging from 0.005 to 2 ppm in such diverse matrixes as carrots, lettuce, peanut butter, hamburger, and fortified butter fat and fortified potatoes. SC-CO2 provides a solvent medium that is nontoxic, nonflammable, and inexpensive while also eliminating the use and disposal of potentially carcinogenic organic solvents.     

Countercurrent supercritical fluid extraction and fractionation of high-added-value compounds from a hexane extract of olive leaves

Countercurrent supercritical fluid extraction (CC-SFE) at a pilot scale plant was used for fractionation of high-added-value products from a raw extract of olive leaves in hexane. Compounds found in the raw extract were waxes, hydrocarbons, squalene, beta-carotene, triglycerides, alpha-tocopherol, beta-sitosterol, and alcohols. The CC-SFE extraction process was investigated according to a 2(3) full factorial experimental design using the following variables and ranges: extraction pressure, 75-200 bar; extraction temperature, 35-50 degrees C; and ethanol as modifier, 0-10%. Data were analyzed in terms of extraction yield, enrichment, recovery, and selectivity. Higher extraction yields were attained at 200 bar. For most of the compounds analyzed enrichment was attained at the same conditions, that is, 75 bar, 35 degrees C, and 10% ethanol. Hydrocarbons were usually recovered in the separators, whereas waxes and alpha-tocopherol remain in the raffinate. Selectivity data reveal that alpha-tocopherol is the most easily separable compound. The influence of the experimental factors on the recovery of all the compounds was studied by means of regression models. The best fitted model was attained for beta-sitosterol, with R2 = 99.25%.     

超临界CO2流体萃取海滨锦葵籽油的工艺条件优化

为了提高海滨锦葵籽的利用价值,开发生物柴油新原料,该文以海滨锦葵籽为原料,利用超临界CO2流体萃取技术提取海滨锦葵籽油。通过单因素试验及正交试验研究了萃取压力、萃取温度、CO2流量和萃取时间等因素对油脂得率的影响,确定了超临界CO2流体萃取技术提取海滨锦葵籽油的最佳工艺条件。结果表明,在试验范围内各影响因素对海滨锦葵籽油得率作用的大小依次为：萃取压力＞萃取温度＞CO2流量＞萃取时间。超临界CO2流体萃取技术提取海滨锦葵籽油的最佳工艺参数为：萃取压力25 MPa,萃取温度45℃,CO2流量21 kg/h,萃取时间为100 min,在该工艺条件下萃取3次,海滨锦葵籽油得率达到19.35%。     

超临界CO_2流体萃取杨梅核仁油的工艺优化

以杨梅核仁为原料,研究超临界CO2流体静、动态结合萃取杨梅核仁油的工艺条件,利用单因素试验与正交试验进行优化,得到最佳萃取方案,即萃取压力35MPa,萃取温度45℃,静态萃取60min后动态萃取50min,CO2流量4L/min,杨梅核仁油的得率最高,达41.7%。     

Isolation of antioxidant compounds from orange juice by using countercurrent supercritical fluid extraction (CC-SFE).

Antioxidants from orange juice are isolated by the use of countercurrent supercritical fluid extraction (CC-SFE) and characterized by reversed-phase liquid chromatography (RPLC) coupled to mass spectrometry (MS) and diode-array detection (DAD). A pilot-scale SFE plant equipped with a packed column has been employed for countercurrent extraction and fractionation of raw orange juice with carbon dioxide. Several experiments have been performed in order to study the effect of the countercurrent conditions on the content of antioxidative compounds. In this study, the main variable that has been considered is the solvent-to-feed ratio (S/F) because it plays an essential role in the extraction efficiency. The values tested covered a wide range of sample and solvent (CO(2)) flow rates. In each experimental run, two different extracted fractions and the residual nonextracted juice were obtained and characterized. Different flavonoids have been identified in the fractions obtained after CC-SFE. The possibility of using this process for antioxidant compounds enrichment is discussed.     

Comparison of the chemical composition of extracts from Scutellaria lateriflora using accelerated solvent extraction and supercritical fluid extraction versus standard hot water or 70% ethanol extraction

The aqueous extract of American skullcap (Scutellaria lateriflora L. (S. lateriflora), Lamiaceae) has been traditionally used by North American Indians as a nerve tonic and for its sedative and diuretic properties. Recent reports stated that flavonoids and possibly amino acids are responsible for the anxiolytic activity. As a part of our search for environmentally friendly solvents to extract the active components from medicinal plants, we used S. lateriflora in a comparison of accelerated solvent extraction (ASE) using water, and supercritical fluid extraction (SFE) using CO2 and 10% EtOH as modifier, at different temperatures. Flavonoids and amino acids were quantified by HPLC-UV and HPLC-MS, respectively. The flavonoid content was compared with conventional extraction methods (hot water extraction and 70% ethanol). The use of ASE at 85 degrees C with water as solvent gave the best results for flavonoid glycosides and amino acids, whereas SFE gave higher yields of flavonoid aglycones. However, the results obtained for total flavonoids were not significatively superior to hot water extraction or 70% aqueous EtOH extract.     

Determination of the fluoroquinolone enrofloxacin in edible chicken muscle by supercritical fluid extraction and liquid chromatography with fluorescence detection

A supercritical fluid extraction (SFE) method for the extraction of enrofloxacin from a chicken breast muscle was examined. A liquid chromatograph, equipped with a fluorescence detector, was used for the detection of enrofloxacin. Optimal extraction parameters, such as extraction time, supercritical fluid volume, modifier concentration, pressure, and temperature, were determined by examining SFE recoveries from control muscle samples spiked with enrofloxacin at different levels. In all of the experiments, high recovery values were observed, ranging from 101 to 104%. The extraction of enrofloxacin from real muscle samples was examined in chickens that were treated orally with enrofloxacin. Extraction was carried out by the SFE method after each oral treatment and under optimal extraction conditions at set intervals over time. The SFE, combined with liquid chromatographic analysis, showed that the concentration of enrofloxacin in the chicken muscles decreased continuously with time, giving a negligible concentration 72 h after the treatment. These results suggest that SFE is a useful approach for the extraction of enrofloxacin from chicken breast muscles.     

Isolation of tetra-acyl sucrose esters from turkish tobacco using supercritical fluid CO2 and comparison with conventional solvent extraction

Pure supercritical CO2 at various pressures and temperatures was used to effect the fractionation of tetra-acyl sucrose esters (SE) from dried, ground Turkish tobacco without any further pretreatment of the matrix. It was determined that SE cannot be extracted using low density CO2 (150 atm, 60 degrees C, and 0.62 gm/mL or 200 atm, 100 degrees C, and 0.49 gm/mL), whereas other analytes, which strongly interfere with the conventional solvent extraction of SE, can be easily removed under the same conditions. At the higher temperature (100 degrees C), these same analytes that interfere with the conventional solvent extraction of SE are even more readily removed, while the very poor extractability of SE is not affected. It was demonstrated, however, that SE can be removed from the pre-extracted tobacco with supercritical CO2 if the density is greater than (or equal to) 0.73 gm/mL. The supercritical fluid extraction method has been compared with other previous extraction methods that employ conventional solvents. This study provides one of the clearest examples of how the variable density property of a supercritical fluid can be utilized to effect the fractionation of a complex mixture.     

Optimization of a supercritical fluid extraction/reaction methodology for the analysis of castor oil using experimental design

The aim of this work was to optimize a supercritical fluid extraction (SFE)/enzymatic reaction process for the determination of the fatty acid composition of castor seeds. A lipase from Candida antarctica (Novozyme 435) was used to catalyze the methanolysis reaction in supercritical carbon dioxide (SC-CO(2)). A Box-Behnken statistical design was used to evaluate effects of various values of pressure (200-400 bar), temperature (40-80 degrees C), methanol concentration (1-5 vol %), and water concentration (0.02-0.18 vol %) on the yield of methylated castor oil. Response surfaces were plotted, and these together with results from some additional experiments produced optimal extraction/reaction conditions for SC-CO(2) at 300 bar and 80 degrees C, with 7 vol % methanol and 0.02 vol % water. These conditions were used for the determination of the castor oil content expressed as fatty acid methyl esters (FAMEs) in castor seeds. The results obtained were similar to those obtained using conventional methodology based on solvent extraction followed by chemical transmethylation. It was concluded that the methodology developed could be used for the determination of castor oil content as well as composition of individual FAMEs in castor seeds.     

Evaluation of supercritical fluid extraction/aminopropyl solid-phase "in-line" cleanup for analysis of pesticide residues in rice

Supercritical fluid extraction (SFE) and the use of aminopropyl solid-phase material for "in-line" cleanup was evaluated for residue analysis of 22 GC-amenable pesticides in wild- and white-rice samples with a fat content of 1.9 and 0.4%, respectively. After optimizing the extraction conditions on glass beads as inert material and evaluating the fat amount extracted from rice by SFE, the use of Florisil, Celite, Extrelut, Hydromatrix, and an aminopropyl material as fat-retention materials for SFE "in-line" cleanup was assessed, aminopropyl being the most suitable material for this cleanup of fat. Pesticide mean recoveries obtained from rice samples, at fortification levels around 0.5 mg/kg, by means of the SFE/in-line cleanup method finally proposed (15-mL CO2 volume, 50 degrees C temperature, 200 atm pressure, 200 muL of methanol static modifier, and a 1-cm layer of aminopropyl at the bottom of the extraction vessel), ranged between 74 and 98%, except for captafol and dimethoate for which mean recoveries lower than 21% were determined.     

Analysis of antioxidants from orange juice obtained by countercurrent supercritical fluid extraction,using micellar electrokinetic chromatography and reverse-phase liquid chromatography

Antioxidants from orange juice were determined by the combined use of countercurrent supercritical fluid extraction (CC-SFE) prior to reverse-phase liquic chromatography (RP-LC) or micellar electrokinetic chromatography (MEKC). The separation of antioxidants found in the SFE fractions was achieved by using a new MEKC method and a published LC procedure, both using diode array detection. The characterization of the different antioxidants was further done by LC-mass spectrometry. Advantages and drawbacks of LC and MEKC for analyzing the antioxidants found in the different orange extracts are discussed. Although LC yields higher peak area and slightly better reproducibility than MEKC, the latter technique provides information about the CC-SFE extracts in analysis times 7 times faster than by LC. This analysis advantage can be used for the quick adjustment of CC-SFE conditions, thus providing a fast way to obtain orange fractions of specific composition.