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Supercritical Fluid Extraction (supercritical + fluid_extraction)
Selected AbstractsSUPERCRITICAL FLUID EXTRACTION AND DETERMINATION OF LUTEIN IN HETEROTROPHICALLY CULTIVATED CHLORELLA PYRENOIDOSAJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2007ZHENGYUN WU ABSTRACT Chlorella is a promising alternative resource of lutein, as it can be cultivated heterotrophically and efficiently in a fermentor. In this study, high density of Chlorella pyrenoidosa was achieved by fed-batch cultivations. Lutein in Chlorella was extracted by supercritical fluid and was determined by high-performance liquid chromatography and liquid chromatography-mass spectrometry. The extraction degree of lutein reached 87.0% after 4-h extraction under the optimized conditions of 50C, 25 MPa and modified CO2 with 50% ethanol. High purity of lutein could be obtained by supercritical fluid extraction with appropriate operation parameters. The whole process developed in this study may be useful for the commercial production of lutein. [source] Cover Picture: Electrophoresis 15/2008ELECTROPHORESIS, Issue 15 2008Article first published online: 24 JUL 200 Regular issues provide a wide range of research and review articles covering all aspects of electrophoresis. Here you will find cutting-edge articles on methods and theory, instrumentation, nucleic acids, CE and CEC, miniaturization and microfluidics, proteomics and two-dimensional electrophoresis. Selected topics of issue 15 are: The application of perfluorooctanoate to investigate trimerization of the human immunodeficiency virus-1 gp41 ectodomain by electrophoresis Metabolic fingerprinting of schistosoma mansoni infection in mice urine with capillary electrophoresis Supercritical fluid extraction as an on-line clean-up technique for determination of riboflavin vitamins in food samples by capillary electrophoresis with fluorimetric detection A two-step electro-dialysis method for DNA purification from polluted metallic environmental samples. [source] Supercritical fluid extraction of lipids from the heterotrophic microalga Crypthecodinium cohniiENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 2 2010Ricardo Miguel Couto Abstract Microalgae biomass can be a feasible source of ,-3 fatty acids due to its stable and reliable composition. In the present study, the Crypthecodinium cohnii growth and docosahexaenoic acid (DHA, 22:6,3) production in a 100,L glucose-fed batch fermentation was evaluated. The lipid compounds were extracted by supercritical carbon dioxide (SC-CO2) from C. cohnii CCMP 316 biomas, was and their fatty acid composition was analysed. Supercritical fluid extraction runs were performed at temperatures of 313 and 323,K and pressures of 20.0, 25.0 and 30.0,MPa. The optimum extraction conditions were found to be 30.0,MPa and 323,K. Under those conditions, almost 50% of the total oil contained in the raw material was extracted after 3,h and the DHA composition attained 72%,w/w of total fatty acids. The high DHA percentage of total fatty acids obtained by SC-CO2 suggested that this extraction method may be suitable for the production of C. cohnii value added products directed towards pharmaceutical purposes. Furthermore, the fatty acid composition of the remaining lipid fraction from the residual biomass with lower content in polyunsaturated fatty acids could be adequate for further uses as feedstock for biodiesel, contributing to the economy of the overall process suggesting an integrated biorefinery approach. [source] Supercritical fluid extraction of walnut kernel oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2006Sema Salg Abstract The objective of this study was to investigate the effects of the main process parameters on supercritical fluid extraction of walnut (Juglans regia,L.) kernel oil. The recovery of walnut kernel oil was performed in a green and high-tech separation process. CO2 and CO2 +,ethanol mixtures were used as the supercritical solvent. The extraction was carried out at operating pressures of 30, 40 and 50,MPa, operating temperatures of 313, 323 and 333,K, mean particle sizes of 1.78×10,4, 3.03×10,4, 4.78×10,4, 7.00×10,4 and 9.00×10,4,m, supercritical CO2 (SC CO2) flow rates of 1.67×10,8, 3.33×10,8, 6.67×10,8 and 13.33×10,8,m3/s and entrainer (ethanol) concentrations of 2, 4, 8 and 12,vol-%. Maximum extraction yield and oil solubility in SC CO2 obtained at 50,MPa, 333,K, 9.00×10,4,m, 3.33×10,4,m3/h were 0.65,kg oil/kg of dry sample and 37.16,g oil/kg CO2, respectively. The results obtained in this study showed that the crossover pressure effect of walnut kernel oil was at 30,MPa. At 30,MPa and 313,K, the obtained extraction yields above 4,vol-% ethanol reached the organic solvent extraction yield of 68.5,kg oil/kg dry sample. Extraction time was decreased significantly because of the higher solubility of walnut kernel oil in SC CO2 +,ethanol mixtures. [source] SUPERCRITICAL CARBON DIOXIDE SELECTIVITY TO FRACTIONATE PHENOLIC COMPOUNDS FROM THE DRY ETHANOLIC EXTRACT OF PROPOLISJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2010LOSIANE C. PAVIANI ABSTRACT The global yield and composition of extracts obtained by supercritical carbon dioxide (SC-CO2) extraction from a dry ethanolic extract of propolis were measured in order to determine the possibility of using SC-CO2 to fractionate components of interest present in these extracts. The global yield extraction was measured, and also the concentrations of the following phenolic compounds in the resulting supercritical fluid extracts (SFEs): 3,5-diprenyl-4-hydroxycinnamic acid (known as artepillin C), 3-prenyl-4-hydroxycinnamic acid, 4-hydroxycinnamic acid (p- coumaric acid) and 4-methoxy-3,5,7-trihydroxyflavone (kaempferide), of which artepillin C was the target component of greatest interest. The results showed extraction yields between 3.82 (at 150 bar) and 13.07% (at 350 bar), which could be highly correlated with the density of the SC-CO2 at a constant temperature of 60C. The resulting concentrations in the SFE indicated that the selectivity of the carbon dioxide could be manipulated, and it was more selective at lower pressures, although with lower extraction yields. PRACTICAL APPLICATIONS Supercritical fluid extraction is an interesting process for the production of natural extracts because it is a clean process, and extractions using carbon dioxide (CO2) as the solvent have been gaining attention in recent years. This study presented important aspects with respect to the fractionation of a dry ethanolic extract of propolis using supercritical carbon dioxide, and it is important to explore the potential applications of propolis extracts and the biological properties of its fractions in the food, pharmaceutical and cosmetic industries, such as in dental hygiene products, wound healing creams and antibacterial soaps. [source] An efficient combination of supercritical fluid extraction and high-speed counter-current chromatography to extract and purify homoisoflavonoids from Ophiopogon japonicus (Thunb.) Ker-GawlerJOURNAL OF SEPARATION SCIENCE, JSS, Issue 11 2009Chengjun Ma Abstract Supercritical fluid extraction (SFE) was used to extract homoisoflavonoids from Ophiopogon japonicus (Thunb.) Ker-Gawler. The optimization of parameters was carried out using an orthogonal test L9 (3)4 including pressure, temperature, dynamic extraction time and the amount of modifier. The process was then scaled up by 100 times with a preparative SFE system under the optimized conditions of 25 MPa, 55°C, 4.0 h and 25% methanol as a modifier. Then crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n -hexane/ethyl acetate/methanol/ACN/water (1.8:1.0:1.0:1.2:1.0 v/v). There three homoisoflavonoidal compounds including methylophiopogonanone A 6-aldehydo-isoophiopogonone A, and 6-formyl-isoophiopogonanone A, were successfully isolated and purified in one step. The collected fractions were analyzed by HPLC. In each operation, 140 mg crude extracts was separated and yielded 15.3 mg of methylophiopogonanone A (96.9% purity), 4.1 mg of 6-aldehydo-isoophiopogonone A (98.3% purity) and 13.5 mg of 6-formyl-isoophiopogonanone A (97.3% purity) respectively. The chemical structure of the three homoisoflavonoids are identified by means of ESI-MS and NMR analysis. [source] Enrichment of the thymoquinone content in volatile oil from Satureja montana using supercritical fluid extractionJOURNAL OF SEPARATION SCIENCE, JSS, Issue 2 2009Clara Grosso Abstract Supercritical fluid extraction (SFE) of the volatile oil from Satureja montana L. was performed under different conditions of pressure (90 and 100 bar), temperature (40 and 50°C), mean particle sizes (0.4, 0.6 and 0.8 mm) and CO2 flow rate (0.8, 1.1 and 1.3 kg/h) to understand the influence of these parameters on the composition and yield of this oil. The results were compared with those obtained for the essential oil isolated by hydrodistillation (HD). The volatile and the essential oil were analysed by GC and GC-MS. The main compounds are carvacrol (52.2,62.0% for HD vs. 41.7,64.5% for SFE), thymol (8.6,11.0% for HD vs. 6.0,11.3% for SFE), p -cymene (6.9,12.8% for HD vs. 6.0,17.8% for SFE), ,-terpinene (6.4,9.4% for HD vs. 2.3,6.0% for SFE) and ,-bisabolene (2.0,2.7% for HD vs. 2.2,3.5% for SFE). The major difference between SFE and HD was the relative amount of thymoquinone, an oxygenated monoterpene with important biological activities, which can be ten-fold higher in volatile oil (1.6,3.0 for SFE vs. 0.2% for HD). The morphology of the glandular trichomes of S. montana and the effect of the grinding process on them was also evaluated by SEM. [source] Supercritical fluid extraction of cynaropicrin and 20-hydroxyecdysone from Leuzea carthamoides DCJOURNAL OF SEPARATION SCIENCE, JSS, Issue 8 2008Helena Sovová Abstract Leuzea carthamoides is an adaptogenic plant containing biologically active compounds as ecdysteroids and guaianolide-type sesquiterpene lactones, conventionally extracted from the plant with ethanol. It may be a potential source of the mentioned natural compounds. Ethanol-modified near-critical CO2 was used as selective solvent with the aim to increase the level of 20-hydroxyecdysone in the extract from L. carthamoides roots and to remove selectively cynaropicrin, a sesquiterpene lactone of bitter taste, from the leaves. The extraction conditions were varied (pressure 20,28 MPa, temperature 40,60°C, ethanol concentration in the solvent 0,7.1%) and the extraction yield and extract composition were compared with the results of ethanolic extraction. The supercritical fluid extraction (SFE) from finely powdered plant was controlled by phase equilibrium. Cynaropicrin was quantitatively removed from the leaves where 89% of 20-hydroxyecdysone was retained. The extraction yield of 20-hydroxyecdysone from roots with ethanol-modified CO2 was lower by 30% than with ethanol but its concentration in the extract was higher by 67%. [source] Supercritical fluid extraction of ecdysterone from the roots of Achyranthes bidentata BL.JOURNAL OF SEPARATION SCIENCE, JSS, Issue 8 2008Yizhe Zheng Abstract Ecdysterone has been found in a great many plants and animals and has some valuable pharmaceutical properties. The present study was conducted to investigate optimal conditions for the extraction of the compound by supercritical fluid extraction from the roots of Achyranthes bidentata BL. An orthogonal array design (OAD), OA9(34), was employed as a chemometric method for optimization of the extraction of ecdysterone from the herbal medicine. Four parameters, namely, pressure and temperature of the supercritical fluid, the dynamic extraction time, and the flow rate of dimethyl sulfoxide, were studied and optimized by a three-level OAD. Determinations of the extracts were performed by high-performance liquid chromatography. The effects of the parameters were studied using analysis of variance. The results shown that the yield of ecdysterone could be influenced by the four parameters to a similar degree. The yield for DMSO-modified supercritical CO2 was in the range from 0.65 to 1.03 mg/g under the selected conditions. In comparison with methanol-modified supercritical CO2 and Soxhlet extraction, a higher yield was obtained when DMSO-modified supercritical CO2 was used. [source] Quantification of seed oil from species with varying oil content using supercritical fluid extractionPHYTOCHEMICAL ANALYSIS, Issue 6 2008Charlotte E. Seal Abstract Introduction: The quantity and composition of seed oil affects seed viability and storability and hence the value of a species as a resource for nutrition and plant conservation. Supercritical fluid extraction with carbon dioxide (SFE-CO2) offers a rapid, environmentally friendly alternative to traditional solvent extraction. Objective: To develop a method using SFE-CO2 to quantify the seed oil content in a broad range of species with high to low oil contents. Methodology: Seed oil was extracted using SFE-CO2 from four crop species representing high, medium and low oil content: Helianthus annuus, Asteraceae, with ca. 55% oil; Brassica napus, Brassicaceae, with ca. 50% oil; Glycine max, Fabaceae, with ca. 20% oil; and Pisum sativum, Fabaceae, with ca. 2% oil. Extraction pressures of 5000, 6000 and 7500 psi and temperatures of 40, 60 and 80°C were examined and a second step using 15% ethanol as a modifier included. Oil yields were compared with that achieved from Smalley Butt extraction. The optimised SFE-CO2 method was validated on six species from taxonomically distant families and with varying oil contents: Swietenia humilis (Meliaceae), Stenocereus thurberi (Cactaceae), Sinapis alba (Brassicaceae), Robinia pseudoacacia (Fabaceae), Poa pratensis (Poaceae) and Trachycarpus fortunei (Arecaceae). Results: The two-step extraction at 6000 psi and 80°C produced oil yields equivalent to or higher than Smalley Butt extraction for all species, including challenging species from the Brassicaceae family. Conclusion: SFE-CO2 enables the rapid analysis of seed oils across a broad range of seed oil contents. Copyright © 2008 John Wiley & Sons, Ltd. [source] Rapid techniques for the extraction of vitamin E isomers from Amaranthus caudatus seeds: ultrasonic and supercritical fluid extractionPHYTOCHEMICAL ANALYSIS, Issue 5 2002Renato Bruni Abstract Supercritical fluid extraction (SFE) of seeds of Amaranthus caudatus (Amaranthaceae) and the use of ultrasound as a co-adjuvant in the extraction process were compared with methods traditionally used in the extraction of tocopherols and fatty acids. The use of readily available ultrasound equipment as an adjunct to the classical methods employed for the extraction of tocols provided qualitatively acceptable results more rapidly and more economically. SFE gave quantitatively better yields in shorter times, with solvent-free extracts obtained under conditions that minimised the degradation of thermolabile components. No significant variations were observed in the profile of the fatty acids extracted from amaranth oil by SFE or other methods, thus confirming the qualitative comparability of the faster supercritical extraction with the more time-consuming classical techniques even when processed with the aid of ultrasound. Copyright © 2002 John Wiley & Sons, Ltd. [source] Supercritical fluid extraction for the separation of organochlorine pesticides residue in Angelica sinensisBIOMEDICAL CHROMATOGRAPHY, Issue 7 2002Chunjie Zhao A method involving the simultaneous extraction and separation of 12 organochlorine pesticides (OCPs) from Angelicae sinensis was developed using supercritical fluid extraction (SFE). The pesticides in the study were ,-, ,-, ,- and ,-benzene hexachloride, PCNB (pentachloro- nitrobenzene), PCA (pentachloroaniline), HEPT (heptachlor), MPCPS (methyl-pentachlorophenyl sulfide), pp,-DDE [1,1-dichloro-2,2-bis (p -chlorophenyl) ethylene], op,-DDT [1,1,1,-trichloro-2-(o -chlorophenyl)-2-(p -chlorophenyl) ethane], pp,-DDD [1,1-dichloro-2,2-bis(p -chlorophenyl) ethane], and pp,-DDT [1,1,1,-trichloro-2,2-bis (p -chlorophenyl)ethane]. The extraction conditions were optimized as follows: pure CO2, extraction pressure 15 MPa, extraction temperature 60°C, extraction time 20,min, and flow-rate 1.5,mL/min. A GC method with electron capture detection was employed to determine the OCPs in Angelicae sinensis. An HPLC method was developed for the quantitative determination of active constituents. The SFE provided high decontamination rate of OCPs and low loss of active constituents in Angelicae sinensis. Copyright © 2002 John Wiley & Sons, Ltd. [source] Effects of Operating Parameters on the Cinnamaldehyde Content of Extracted Essential Oil Using Various MethodsCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 2 2010H. Baseri Abstract Supercritical fluid extraction (SFE) of essential oils from commercial cinnamon bark was compared with essential oils that were obtained by hydrodistillation. Effects of operating parameters (pressure, temperature and extraction time of SFE) on the extraction yield and the composition of the extracted volatile oil were studied. Moreover, in the hydrodistillation process, the effect of the pH of the solvent on the concentration of cinnamaldehyde in the extracted volatile oil was studied. The maximum yield of extract in the SFE process is about 7.8,% at 70,°C and 240,bar. The maximum concentration of cinnamaldehyde in the SFE process was obtained at 70,°C and 160,bar, and the maximum concentration of this component in hydrodistillation was achieved at pH,=,4.1. [source] Simultaneous determination of six non-polar heterocyclic amines in meat samples by supercritical fluid extraction,capillary electrophoresis under fluorimetric detectionELECTROPHORESIS, Issue 13 2010Fernando De Andrés Abstract A novel, sensitive and selective method for the separation and quantification of a group of non-polar heterocyclic amines (9H-pyrido-[3,4-b] indole, norharmane; 1-methyl-9H-pyrido-[3,4-b] indole, harmane; 2-amino-9H-pyrido-[2,3-b] indole, A,C; 2-amino-3-methyl-9H-pyrido-[2,3-b] indole, MeA,C; 3-amino-1,4-dimethyl-5H-pyrido-[4,3-b] indole, Trp-P-1 and 3-amino-1-methyl-5H-pyrido-[4,3-b] indole, Trp-P-2) in commercial meat samples has been developed. This methodology is faster than others previously described. The method is based on the combination of a supercritical fluid extraction procedure, followed by the analysis of the extracted plug by CE with fluorescence detection. The supercritical fluid extraction procedure was optimized for the clean-up of the samples and the extraction of the analytes. For the electrophoretic separation, the effect of composition, pH and concentration of buffer, organic modifier content, pressure and time of injection, capillary temperature and voltage applied were studied. A 10,mmol/L formic acid,ammonium formate,ACN (10%, v/v) solution at pH 1.5 was selected as the running electrolyte. With 5-s hydrodynamic injection, linear responses in the range from 100 to 1000,ng/mL and detection limits ranging from 15.9 to 28.1,ng/mL were obtained for different amines in less than 13,min. ACN,water (1:1 in volume) was used as a sample solvent. Fluorescence detection enhances the sensitivity and avoids interferences coming from non-fluorescent compounds present in the matrices of the sample extracts. [source] Application of supercritical fluid extraction to regenerate spent Pd-active carbon catalystENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 4 2007Lidia D Abstract Pd-active carbon-type catalysts are used in a wide variety of processes, typical examples of which are liquid-phase hydrogenation reactions. In the case of these catalysts, a loss of their catalytic activity is observed. The aim of the present work was to assess the possibility of regenerating spent Pd/AC catalysts using supercritical fluid extraction. The following Pd/AC catalyst samples were investigated and compared: a commercial 10 wt % Pd catalyst (Aldrich) (denoted by CC), a spent catalyst (SC), SC subjected to supercritical fluid,CO2 extraction (SC/SFE/C), SC subjected to supercritical fluid,CO2,ethanol extraction (SC/SFE/C-Et), and SC subjected to supercritical fluid,ethane,propane extraction (SC/SFE/E-P). The last three catalysts were additionally subjected to heating in a hydrogen atmosphere at 410 K for 3 h. These were denoted by SC/SFE/C/H, SC/SFE/C-Et/H, and SC/SFE/E-P/H, respectively. The spent Pd/AC catalyst (SC) consists of mixed CC samples used in the reduction with hydrogen of various organic compounds. The catalysts CC, SC/SFE/C, SC/SFE/C/H, SC/SFE/C-Et/H, and SC/SFE/E-P/H were tested in the reduction of octanoylbenzene with hydrogen. The activity of the catalysts was estimated by measuring the reaction time and also the amount of hydrogen used in relation to the theoretical quantity required for the reaction. XPS and XRD methods were used to evaluate the changes occurring in the form of the palladium present on the Pd/AC catalyst surface during the regeneration processes. It was found that supercritical fluid-CO2 extraction followed by heating in a hydrogen atmosphere is the most effective method for regenerating that catalyst. The results of our investigations indicate that regeneration of a spent Pd/AC catalyst, irrespective of the reaction in which it has been used, should be based on the complete removal of byproducts, the purification of the catalyst surface, and the restoration of the original form of the palladium. The procedure proposed in this paper, i.e. SFE (CO2) and heating in H2, fulfils both the conditions mentioned above. © 2007 American Institute of Chemical Engineers Environ Prog, 2007 [source] Effect of various extraction conditions on the phenolic contents of pomegranate seed oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 5 2008Hajar Abbasi Abstract Pomegranate seeds are byproducts of the pomegranate juice industry. Because of the presence of large amounts of certain pharmaceutical and nutraceutical components in the seeds, a proper extraction method to obtain these components is highly demanded in the food industry. In this study, the effect of different extraction methods on the total phenolic contents of the oil extracted from pomegranate seeds of the Malas variety from Shahreza, Iran, was investigated. Four different extraction methods including normal stirring, Soxhlet, microwave irradiation and ultrasonic irradiation using two types of organic solvents as well as a supercritical fluid extraction (SFE) method using CO2 as solvent were applied. The different organic solvents of this study did not indicate any significant differences in the total phenolic contents of the extracted oils, but the extracted oils from the various conditions of SFE indicated wide changes in the amount of phenolic compounds (7.8,72.1,mg/g). The total phenolic content of the extracted oil from one of the SFE runs was several times greater than those in the extracted oils using organic solvents. [source] Supercritical fluid extraction of walnut kernel oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2006Sema Salg Abstract The objective of this study was to investigate the effects of the main process parameters on supercritical fluid extraction of walnut (Juglans regia,L.) kernel oil. The recovery of walnut kernel oil was performed in a green and high-tech separation process. CO2 and CO2 +,ethanol mixtures were used as the supercritical solvent. The extraction was carried out at operating pressures of 30, 40 and 50,MPa, operating temperatures of 313, 323 and 333,K, mean particle sizes of 1.78×10,4, 3.03×10,4, 4.78×10,4, 7.00×10,4 and 9.00×10,4,m, supercritical CO2 (SC CO2) flow rates of 1.67×10,8, 3.33×10,8, 6.67×10,8 and 13.33×10,8,m3/s and entrainer (ethanol) concentrations of 2, 4, 8 and 12,vol-%. Maximum extraction yield and oil solubility in SC CO2 obtained at 50,MPa, 333,K, 9.00×10,4,m, 3.33×10,4,m3/h were 0.65,kg oil/kg of dry sample and 37.16,g oil/kg CO2, respectively. The results obtained in this study showed that the crossover pressure effect of walnut kernel oil was at 30,MPa. At 30,MPa and 313,K, the obtained extraction yields above 4,vol-% ethanol reached the organic solvent extraction yield of 68.5,kg oil/kg dry sample. Extraction time was decreased significantly because of the higher solubility of walnut kernel oil in SC CO2 +,ethanol mixtures. [source] Use of ionic liquids as ,green' solvents for extractionsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 10 2005Hua Zhao Abstract This review summarizes recent applications of ionic liquids (ILs) as ,green' solvents in extractions of a variety of substances, including metal ions, organic and bio-molecules, organosulfur from fuels, and gases. ILs could also be used along with another ,green' technology, supercritical fluid extraction (SFE), for a more effective separation of products from ILs. In addition to their environmentally-benign feature, ILs have other favorable properties over organic solvents used for extraction, such as adjustable hydrophobicity, polarity and selectivity. Copyright © 2005 Society of Chemical Industry [source] EVALUATION OF GLOBAL YIELD, COMPOSITION, ANTIOXIDANT ACTIVITY AND COST OF MANUFACTURING OF EXTRACTS FROM LEMON VERBENA (ALOYSIA TRIPHYLLA[L'HÉRIT.] BRITTON) AND MANGO (MANGIFERA INDICA L.) LEAVESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2007CAMILA G. PEREIRA ABSTRACT In this work, the global yields, composition and antioxidant activity (AA) of extracts from lemon verbena (Aloysia triphylla) and mango (Mangifera indica) leaves obtained by different separation processes were determined. Lemon verbena extracts were obtained by supercritical fluid extraction (SFE), while mango leaf extracts were obtained by SFE, low-pressure solvent extraction (LPSE) and hydrodistillation. The extract's constituents were analyzed by thin-layer chromatography, gas chromatography/mass spectrometry and gas chromatography/flame ionization detector. The AA of the extracts was evaluated by the coupled reaction of , -carotene/linolenic acid. The cost of manufacturing (COM) was estimated for the SFE extracts. Higher global yields were obtained using SFE at 350 bar/45C (1.49%) for lemon verbena and LPSE (3.04%) for mango. The AAs of the extracts were larger than that of the , -carotene for both plants. The minimum values of COM were U.S.$26.96 and 52.45/kg of extract for lemon verbena and mango, respectively. [source] SUPERCRITICAL FLUID EXTRACTION AND DETERMINATION OF LUTEIN IN HETEROTROPHICALLY CULTIVATED CHLORELLA PYRENOIDOSAJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2007ZHENGYUN WU ABSTRACT Chlorella is a promising alternative resource of lutein, as it can be cultivated heterotrophically and efficiently in a fermentor. In this study, high density of Chlorella pyrenoidosa was achieved by fed-batch cultivations. Lutein in Chlorella was extracted by supercritical fluid and was determined by high-performance liquid chromatography and liquid chromatography-mass spectrometry. The extraction degree of lutein reached 87.0% after 4-h extraction under the optimized conditions of 50C, 25 MPa and modified CO2 with 50% ethanol. High purity of lutein could be obtained by supercritical fluid extraction with appropriate operation parameters. The whole process developed in this study may be useful for the commercial production of lutein. [source] Hindered diffusion of residue narrow cuts through polycarbonate membranesAICHE JOURNAL, Issue 8 2010Zhentao Chen Abstract Hindered diffusion plays an important role in catalytic processing of residue and heavy oil because of large size molecules in these feedstocks. Vacuum residue of Athabasca oil sand bitumen was fractionated into 13 narrow fractions and an end-cut by supercritical fluid extraction and fractionation (SFEF). Diffusion transport of five SFEF cuts through four polycarbonate membranes was investigated using a diaphragm cell at 308 K. The results showed that diffusion coefficients of the five SFEF cuts decreased as the experiment proceeded, which illustrates that these cuts are polydisperse in size. The effective diffusion coefficients varied with molecular size and pore size. Hindered diffusion of the five SFEF cuts is significant in the membranes with nominal pore diameter of 15 nm, which is around the average pore size of typical hydrotreating catalyst. Comparisons between experimental data and theoretical prediction revealed that the actual hindered degree for diffusion of the five SFEF cuts is higher than that calculated by the Renkin equation. There were slight differences in diffusivity among saturate, aromatic, and resin constituents. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source] Behavior of an organic solvent drop during the supercritical extraction of emulsionsAICHE JOURNAL, Issue 5 2010Facundo Mattea Abstract The behavior of a drop of dichloromethane in water in contact with CO2 at high pressure has been investigated with the purpose of analyzing the phenomena that takes place during the supercritical fluid extraction of emulsions process. Experiments have been performed with and without a solute (,-carotene) and a surfactant (n -octenylsuccinic anhydride-modified starch) dissolved in the drop, and the evolution of the drop volume as well as of the interfacial tension between the drop and the aqueous phase has been measured. Additionally, a mathematical model has been developed that allows describing the mass transfer. Results show that the drop undergoes swelling and shrinking processes due to diffusion of CO2 into the drop and dichloromethane out of the drop. CO2 concentration in the drop can be as high as 0.9 (molar fraction). Emulsion drops behave as miniature gas antisolvent precipitators and many particles are formed inside the drop. The interfacial tension between the drop and the aqueous phase increases during the process, therefore destabilizing the emulsion. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Drug encapsulation using supercritical fluid extraction of emulsionsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 3 2006P. Chattopadhyay Abstract The current work was aimed at evaluating a new method, supercritical fluid extraction of emulsions (SFEE), for the production of composite (e.g., polymer-drug) micro- and nanoparticles, intended for application in sustained-release drug delivery formulations. Using the proposed method, composite particles were obtained, both in a continuous or batch manner by supercritical carbon dioxide extraction of oil-in-water (o/w) emulsions. Model drugs indomethacin and ketoprofen and biodegradable polymers poly(lactic/glycolic) acid and Eudragit RS were used in order to demonstrate the effectiveness of the SFEE process for producing these particles. Stable aqueous suspensions of composite micro and nanoparticles, having sizes ranging between 0.1 and 2 µm were consistently obtained. Emulsion droplet diameter was found to be the major size control parameter. Other parameters investigated included polymer and drug concentrations in solvent and emulsion solvent fraction. The residual solvent content in the particle suspension obtained was consistently below 50 ppm. Standard dissolution tests were used to observe the sustained release phenomenon of the composite particles. The dissolution profile was characterized in terms of the intrinsic dissolution kinetic coefficients taking into account the specific surface area and solubility of the particles. It was observed that the kinetic coefficient parameter for encapsulated drugs was reduced by 2,4 orders of magnitude when compared to the unprocessed drug particles. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95:667,679, 2006 [source] An efficient combination of supercritical fluid extraction and high-speed counter-current chromatography to extract and purify homoisoflavonoids from Ophiopogon japonicus (Thunb.) Ker-GawlerJOURNAL OF SEPARATION SCIENCE, JSS, Issue 11 2009Chengjun Ma Abstract Supercritical fluid extraction (SFE) was used to extract homoisoflavonoids from Ophiopogon japonicus (Thunb.) Ker-Gawler. The optimization of parameters was carried out using an orthogonal test L9 (3)4 including pressure, temperature, dynamic extraction time and the amount of modifier. The process was then scaled up by 100 times with a preparative SFE system under the optimized conditions of 25 MPa, 55°C, 4.0 h and 25% methanol as a modifier. Then crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n -hexane/ethyl acetate/methanol/ACN/water (1.8:1.0:1.0:1.2:1.0 v/v). There three homoisoflavonoidal compounds including methylophiopogonanone A 6-aldehydo-isoophiopogonone A, and 6-formyl-isoophiopogonanone A, were successfully isolated and purified in one step. The collected fractions were analyzed by HPLC. In each operation, 140 mg crude extracts was separated and yielded 15.3 mg of methylophiopogonanone A (96.9% purity), 4.1 mg of 6-aldehydo-isoophiopogonone A (98.3% purity) and 13.5 mg of 6-formyl-isoophiopogonanone A (97.3% purity) respectively. The chemical structure of the three homoisoflavonoids are identified by means of ESI-MS and NMR analysis. [source] Enrichment of the thymoquinone content in volatile oil from Satureja montana using supercritical fluid extractionJOURNAL OF SEPARATION SCIENCE, JSS, Issue 2 2009Clara Grosso Abstract Supercritical fluid extraction (SFE) of the volatile oil from Satureja montana L. was performed under different conditions of pressure (90 and 100 bar), temperature (40 and 50°C), mean particle sizes (0.4, 0.6 and 0.8 mm) and CO2 flow rate (0.8, 1.1 and 1.3 kg/h) to understand the influence of these parameters on the composition and yield of this oil. The results were compared with those obtained for the essential oil isolated by hydrodistillation (HD). The volatile and the essential oil were analysed by GC and GC-MS. The main compounds are carvacrol (52.2,62.0% for HD vs. 41.7,64.5% for SFE), thymol (8.6,11.0% for HD vs. 6.0,11.3% for SFE), p -cymene (6.9,12.8% for HD vs. 6.0,17.8% for SFE), ,-terpinene (6.4,9.4% for HD vs. 2.3,6.0% for SFE) and ,-bisabolene (2.0,2.7% for HD vs. 2.2,3.5% for SFE). The major difference between SFE and HD was the relative amount of thymoquinone, an oxygenated monoterpene with important biological activities, which can be ten-fold higher in volatile oil (1.6,3.0 for SFE vs. 0.2% for HD). The morphology of the glandular trichomes of S. montana and the effect of the grinding process on them was also evaluated by SEM. [source] Supercritical fluid extraction of ecdysterone from the roots of Achyranthes bidentata BL.JOURNAL OF SEPARATION SCIENCE, JSS, Issue 8 2008Yizhe Zheng Abstract Ecdysterone has been found in a great many plants and animals and has some valuable pharmaceutical properties. The present study was conducted to investigate optimal conditions for the extraction of the compound by supercritical fluid extraction from the roots of Achyranthes bidentata BL. An orthogonal array design (OAD), OA9(34), was employed as a chemometric method for optimization of the extraction of ecdysterone from the herbal medicine. Four parameters, namely, pressure and temperature of the supercritical fluid, the dynamic extraction time, and the flow rate of dimethyl sulfoxide, were studied and optimized by a three-level OAD. Determinations of the extracts were performed by high-performance liquid chromatography. The effects of the parameters were studied using analysis of variance. The results shown that the yield of ecdysterone could be influenced by the four parameters to a similar degree. The yield for DMSO-modified supercritical CO2 was in the range from 0.65 to 1.03 mg/g under the selected conditions. In comparison with methanol-modified supercritical CO2 and Soxhlet extraction, a higher yield was obtained when DMSO-modified supercritical CO2 was used. [source] Comparison of various extraction techniques for isolation and determination of isoflavonoids in plantsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 1 2007Bajer Abstract In the present paper, the following extraction techniques have been used for extracting isoflavonoids from the species Matricaria recutita, Rosmarinus officinalis, Foeniculum vulgare, and Agrimonia eupatoria L.: supercritical fluid extraction (SFE), pressurized fluid extraction, matrix solid phase dispersion, ultrasonic extraction in an ultrasonic bath (USE) and by means of an ultrasonic homogeniser (HOM), extraction by means of Soxhlet apparatus (SOX), and solid phase extraction. Experimental optimization of all techniques has been carried out using a soybean flour. Subsequent analyses of the extracts were carried out by liquid chromatography with UV detection. The maximum yields of daidzein and genistein were obtained by extraction with the SOX, USE, and HOM techniques. The maximum yields of apigenin and biochanin A from herb samples were obtained by SFE. [source] Characterization via liquid chromatography coupled to diode array detector and tandem mass spectrometry of supercritical fluid antioxidant extracts of Spirulina platensis microalgaJOURNAL OF SEPARATION SCIENCE, JSS, Issue 9-10 2005Jose A. Mendiola Abstract Spirulina platensis microalga has been extracted on a pilot scale plant using supercritical fluid extraction (SFE) under various extraction conditions. The extraction yield and the antioxidant activity of the extracts were evaluated in order to select those extracts with both the highest antioxidant capacity and a good extraction yield. These extracts were characterized using LC coupled to diode array detection (DAD) and LC coupled to mass spectrometry (MS) with two different interfaces, atmospheric pressure chemical ionization (APCI) and electrospray (ESI) which allowed us to perform tandem MS by using an ion trap analyzer. The best extraction conditions were as follows: CO2 with 10% of modifier (ethanol) as extraction solvent, 55°C (extraction temperature) and 220 bar (extraction pressure). Fractionation was achieved by cascade depressurization providing two extracts with different activity and chemical composition. Several compounds have been identified in the extracts, corresponding to different carotenoids previously identified in Spirulina platensis microalga along with chlorophyll a and some degradation products. Also, the structure of some phenolic compounds could be tentatively identified. The antioxidant activity of the extracts could be attributed to some of the above mentioned compounds. [source] Supercritical carbon dioxide extraction of sea buckthorn (Hippophae rhamnoides L.) pomaceJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2007Dániel Cossuta Abstract BACKGROUND: The goal of this work was to utilize the sea buckthorn pomace, which is the by-product of a sea buckthorn juice process. Pilot plant supercritical fluid extraction (SFE) experiments were performed in a 5 × 10,3 m3 volume high-pressure vessel. The effects of pressure and temperature on extraction yield and recoveries of biologically active components were studied using a 32 full factorial design. The pressure and temperature were varied over the ranges of 30,46 MPa and 313,353 K, respectively. The extract samples were analysed by TLC-densitometry, UV/VIS spectrofotometry and HPLC methods. RESULTS: The obtained yields changed between 142,164 g kg,1, according to the solvent power of the supercritical fluid. The recoveries of the different minor components were (g minor components kg,1 dried raw material): 2.50,4.25 sitosterol, 0.20,1.60 ursolic acid, 0.04,0.18 carotenoid, 0.35,0.42 total tocopherol. CONCLUSION: By evaluation the designed experiments 46 MPa and 333 K were chosen as the optimum conditions. Copyright © 2007 Society of Chemical Industry [source] Procyanidins: extraction and micro- encapsulationJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2007Lianfu Zhang Abstract As by-products of grape juice and wine production, grape seeds are a rich source of procyanidins but are usually discarded as waste. We have treated grape seeds with supercritical fluid extraction to remove the oils and have extracted the procyanidins from the residues. In order to extend the shelf life, micro-encapsulating methods for procyanidins were studied: the use of gum arabic and maltodextrin as wall materials (the contents of arabic gum and maltodextrin were 40% and 60%, respectively). The raw materials were then mixed (the ratio of core substance to wall material was 30:70 w/w and the content of the slurry was 20% w/v). After homogenisation, spray drying was used to prepare microcapsules. The micro-encapsulation efficiency was up to 88.84%. Analysis of the product showed that the procyanidin was not changed during the processing and the procyanidin microcapsule membrane was uninterrupted and with fairly good integrity. The stability of the products was also obviously improved. Copyright © 2007 Society of Chemical Industry [source] | |||||||||||||||||||||||||