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1.
The possibility of using the tamarillo (Solanum betaceum (Cav.) Sendtn (syn. Cyphomandra betacea)) epicarp as source of compounds with antioxidant activity in cooked beef meat (CBM) was explored. Extracts from tamarillo by supercritical fluid extraction (SFE) and Soxhlet extraction (SE) were obtained. The SFE was performed using pure CO2 at different temperatures and pressures (40 and 50 °C; 10, 20 and 30 MPa) and CO2 added with ethanol (CO2/EtOH) as co-solvent (2, 5 and 8%, w/w). The SFE kinetics and mathematical modeling of the overall extraction curves (OEC) were also investigated. EtOH and hexane were used in the SE. The antioxidant activity (AA) of extracts was evaluated in CBM as well as the protection against lipid oxidation was determined by measuring lipid hydroperoxides (LHP) and thiobarbituric acid reactive species (TBARS). The extract obtained by SFE with CO2/EtOH (50 °C/30 MPa and 2% of EtOH) showed the highest AA. In SFE, the co-solvent addition improved considerably the AA and the extraction yield. The extracts obtained by SFE with CO2/EtOH showed a better AA compared with the synthetic antioxidant TBHQ. The highest yield values were achieved by SE with ethanol (7.7 ± 0.4%) and by SFE with 5% EtOH (1.9 ± 0.1%). The results indicate that extracts of tamarillo epicarp are a potential source of antioxidant compounds.  相似文献   

2.
Supercritical CO2 extraction from microalgae is applied with the aim of obtaining an oil rich in α-linolenic (ALA) essential fatty acid and with a low ω6:ω3 ratio. The maximum extraction yield is obtained at 60 °C and 30 MPa with 0.4 kg/h of CO2 and 5% of co-solvent (ethanol). When the effect of pressure, temperature and density on the supercritical extraction yield and solubility are studied, the thermodynamic cross-over is found at a pressure close to 30 MPa, while the extraction cross-over occurs at around 25 MPa. The experimental solubility data are correlated by literature empirical models. Mathematical models developed by Sovová are applied to describe the experimental extraction curves. Soxhlet extraction of lipids is also carried out, obtaining a similar fatty acids profile but proving to be less selective than SCCO2 method. Among the three species of microalgae examined, results show that Scenedesmus obliquus oil is richer in ω-3 fatty acids and ALA than Chlorella protothecoides and Nannochloropsis salina lipids. The effect of the extraction parameters on ALA content and the fatty acid profile is also analysed, concluding that the ω-3 percentage is favoured by lower temperatures, lower pressures and shorter extraction times.  相似文献   

3.
Microalgae represent diverse branch of microorganism that can produce a wide range of unique functional ingredients that can be used in food, cosmetics, pharmaceuticals, and energy. Among them, Haematococcus pluvialis is known for accumulating the highest levels of a potent natural antioxidant, astaxanthin, which has demonstrated positive health effects. Therefore, the aim of numerous studies has been to develop novel and efficient extraction techniques to produce high-quality (purity and antioxidant activity) extracts, while complying with the Green Chemistry Principles. Supercritical CO2 (scCO2) emerges as an alternative to organic solvents because of its high selectivity and bioactivity-preserving qualities. Nevertheless, astaxanthin is a large molecule with low solubility in scCO2 that usually requires long extractions at high pressures. Ethanol has been used as co-solvent to increase astaxanthin solubility in scCO2. In this work, a Box–Behnken experimental design was used to study the effects of operating pressure (20–35 MPa), temperature (40–70 °C), and ethanol content in scCO2 (0–13%, w/w) on the yield, astaxanthin content, and antioxidant activity of H. pluvialis extract. Results showed that ethanol content in CO2 has a more significant effect on all responses than pressure and temperature. These results lead us to investigate the effect of a further increase in ethanol content, up to the region of gas-expanded liquids. We studied the effects of temperature (30–60 °C) and ethanol content (50–70%, w/w) at a fixed pressure (7 MPa) on the same response variables using CO2-expanded ethanol (CXE). Results showed that temperature and ethanol content had a significant influence on astaxanthin yield and antioxidant activity. Also, the overall responses of CXE surpassed scCO2 extractions to match conventional extraction with acetone, maintaining high quality extracts, thus validating the use of this new type of green technology for extraction of high-value compounds.  相似文献   

4.
In this study the extraction of (−)-Epigallocatechin-3-gallate (EGCG) from Iranian green tea was investigated by supercritical CO2 with ethanol as co-solvent. Design of experiments and modeling were carried out with response surface methodology by Minitab software. The HPLC analysis of the extracted samples was used in conjunction with response surface design to optimize four operating variables of supercritical CO2 extraction (pressure, temperature, CO2 flow rate and extraction dynamic time). Optimum recovery of EGCG (0.462 g/g) was obtained at 19.3 MPa, 43.7 °C, 106 min (dynamic) and 1.5 ml/min (CO2 flow rate). Moreover, a three-layer artificial neural network was developed for modeling EGCG extraction from green tea. In this regard, different networks (by changing the number of neurons in the hidden layer and algorithm of network training) were compared with evaluation of networks accuracy in extraction recovery prediction. Finally, the Levenberg–Marquardt algorithm with the six neurons in the hidden layer has been found to be the most suitable network.  相似文献   

5.
The extraction of lipids from both wet and dry biomass produced by fermentation has been carried out using near-critical dimethylether (DME) as the extraction solvent. Fermentations were carried out from a shake flask up to a 300 L scale using the microorganism Mortierella alpina, and up to a 20 L scale for Phaffia rhodozyma and Agrobacterium tumefaciens. The lipids extracted at a laboratory and pilot scale from the biomasses were enriched in arachidonic acid, astaxanthin, and co-enzyme Q10 respectively. Extractions were also performed on marine microalgae, produced by a proprietary fermentation process, to obtain lipids rich in EPA. Lipids were extracted from wet biomass using DME, which removes the need to dry the biomass. Water is also co-extracted, which has to be separated from the lipid. The biomass shrunk considerably during packed bed extraction of wet biomass, leading to channelling. Repacking and re-extraction of the packed bed enabled full lipid yields to be obtained. The extraction of lipids from biomass suspended in fermentation broth showed considerable promise, and lipid yields were improved due to the recovery of lipids that had been exuded into the broth from the microorganism. In contrast, the extraction of lipids from freeze-dried biomass using DME was routine, yields were substantially higher than using CO2 or CO2 + ethanol, but were lower than from wet biomass. DME also extracted polar lipids from both wet and dry biomass, leading to the higher total lipid yields compared to CO2. Separate extraction of non-polar and polar lipids was possible by sequential extraction of dry biomass using initially CO2 followed optionally with ethanol co-solvent; and then DME.  相似文献   

6.
Near-supercritical and supercritical CO2 was used to extract low-molar-mass phenolics and lipophilic compounds from Pinus pinaster wood. Extraction of samples containing sapwood and knotwood was carried out at 10⿿25 MPa and 30⿿50 °C to assess the influence of the operational conditions on the yields of total extracts and phenolics, as well as on the radical scavenging capacity of extracts. The use of ethanol as a co-solvent increased both the extraction yields and the concentration of phenolics in extracts. Operating under selected conditions (25 MPa, 50 °C, 10% ethanol), the extraction yield accounted for 4.1 wt% of the oven-dry wood. The extracts contained up to 7.6 g of phenolic compounds (measured as gallic acid equivalents) per 100 g extract, and showed one third of the radical scavenging capacity of Trolox. Native resin acids accounted for about 24 g per 100 g extracts, whereas flavonoids, lignans, stilbenes and juvabiones were found at lower proportions.  相似文献   

7.
The knowledge of lipid composition in beer ingredients (malt and corn grits) and wort enables the quality control for final product. Since supercritical fluid extraction (SFE) is an efficient technique for preparing samples for analysis without the use of solvents, in this research Supercritical CO2 (SC–CO2) extraction was compared with the traditional Soxhlet one for a gravimetric determination of total lipids on malt and corn grits. The obtained extracts were then analyzed by HPLC-ELSD after TLC separation of triacylglycerols (TAGs) for lipids fingerprint. The extraction of total fats achieved by a 60-min run with pure CO2 at 65 MPa and 100 °C was 43% higher than that produced by Soxhlet performed for 9 h for malt. The extraction was intermediate for SFE at 60 and 80 °C. The recovery of the TAG obtained with SC–CO2 at 100 °C was statistically comparable with results from Soxhlet extraction.  相似文献   

8.
Carob pulp kibbles, a by-product of carob been gum production, was studied as a source of bioactive agents. Firstly, the carob kibbles were submitted to an aqueous extraction to extract sugars, and supercritical fluid extraction (SFE) was applied to the solid residue of that aqueous extraction, by using compressed carbon dioxide (SC-CO2) as the solvent and a mixture of ethanol and water (80:20, v/v) as a co-solvent. Pressure and temperature were studied in the ranges 15–22 MPa, and 40–70 °C. Particle diameter, and co-solvent percentage in ranges of 0.27–1.07 mm, and 0–12.4%, respectively, were also studied, as well as the flow rate of SC-CO2 between 0.28 and 0.85 kg h−1, corresponding, respectively, to 0.0062 and 0.0210 cm s−1 of superficial velocity. The extracts were characterised in terms of antioxidant capacity by DPPH method, and total phenolics content by the Folin–Ciocalteu method. The central composite non-factorial design was used to optimise the extraction conditions, using the Statistica, version 6 software (Statsoft). The best results, in terms of yield and antioxidant capacity, were found at 22 MPa, 40 °C, 0.27 mm particle size, about 12.4% of co-solvent and a flow rate of 0.29 kg h−1 of SC-CO2. The phenolics profile of the extracts obtained at these conditions was qualitatively evaluated by HPLC-DAD. The solid residue of the supercritical extraction was also studied showing to be a dietary fiber, which can be compared to Caromax™, a carob fiber commercialised by Nutrinova Inc.  相似文献   

9.
Feverfew (Tanacetum parthenium L., Asteraceae) is a perennial medicinal plant which has been used to alleviate the symptoms of migraines, headaches and rheumatoid arthritis. The herb contains various potentially active constituents such as sesquiterpene-γ-lactones, flavonoids and volatile oil. The main sesquiterpene-lactone in feverfew is parthenolide which is considered to be responsible for the therapeutical effects. Supercritical CO2 extraction was carried out at different pressures (10–30 MPa), temperatures (40–80 °C) and co-solvent contents (0–10% ethanol) in order to study the extraction yield and the parthenolide recovery of the extracts. Leaves collected before and during flowering and flower heads were investigated. A factorial experiment using a full 33 design was followed during the experiments and response surface methodology was implemented to analyze the influence of the variables and optimize the extraction. The critical values of parthenolide content were found to be 7% EtOH, 22 MPa and 64 °C in case of all three samples. It was determined, that the optimal conditions of the extraction, where the maximum parthenolide content and extract yield can be reached, do not coincide. The highest yield of parthenolide was obtained in the flower heads (0.604 wt.%).  相似文献   

10.
The objective of this work was to determine the economic feasibility of large-scale operations of supercritical fluid extraction (SFE) for the recovery of phenolics using grape bagasse from Pisco residues. Experimental data were used to estimate the extraction kinetic parameters, as well as the cost of manufacturing the extracts. Experimental data were obtained using supercritical CO2 containing 10% ethanol (w/w) at 313 K and 20–35 MPa. The supercritical CO2/ethanol extraction process produced extracts with higher concentrations of phenolics than extracts produced using conventional techniques. The compounds identified in the extracts were syringic, vanillic, gallic, p-hydroxybenzoic, protocatechuic and p-coumaric acids, as well as quercetin. An evaluation of the economics of the process indicated the feasibility of an industrial SFE plant with a capacity of 0.5 m3 for producing an extract with an expected phenolics concentration of approximately 23 g/kg of extract at an estimated cost of manufacturing of US$ 133.16/kg.  相似文献   

11.
This work explored the potential of subcritical liquids and supercritical carbon dioxide (CO2) in the recovery of extracts containing phenolic compounds, antioxidants and anthocyanins from residues of blueberry (Vaccinium myrtillus L.) processing. Supercritical CO2 and pressurized liquids are alternatives to the use of toxic organic solvents or extraction methods that apply high temperatures. Blueberry is the fruit with the highest antioxidant and polyphenol content, which is present in both peel and pulp. In the extraction with pressurized liquids (PLE), water, ethanol and acetone were used at different proportions, with temperature, pressure and solvent flow rate kept constant at 40 °C, 20 MPa and 10 ml/min, respectively. The extracts were analyzed and the highest antioxidant activities and phenolic contents were found in the extracts obtained with pure ethanol and ethanol + water. The highest concentrations of anthocyanins were recovered with acidified water as solvent. In supercritical fluid extraction (SFE) with CO2, water, acidified water, and ethanol were used as modifiers, and the best condition for all functional components evaluated was SFE with 90% CO2, 5% water, and 5% ethanol. Sixteen anthocyanins were identified and quantified by ultra performance liquid chromatography (UPLC).  相似文献   

12.
The particle sizes of the pharmaceutical substances are important for their bioavailability. The bioavailability can be improved by reducing the particle size of the drug. In this study, salicylic acid and taxol were micronized by the rapid expansion of supercritical fluids (RESS). Supercritical CO2 and CO2 + ethanol mixture were used as solvent. Experiments were carried out to investigate the effect of extraction temperature (318–333 K) and pressure (15–25 MPa), pre-expansion temperature (353–413 K), expansion chamber temperature (273–293 K), spray distance (6–13 cm), co-solvent concentration (ethanol, 1, 2, 3, v/v, %) and nozzle configuration (capillary and orifice nozzle) on the size and morphology of the precipitated salicylic acid particles. For taxol, the effects of extraction pressure (25, 30, 35 MPa) and co-solvent concentration (ethanol, 2, 5, 7, v/v, %) were investigated. The characterization of the particles was determined by scanning electron microscopy (SEM), optical microscopy, and LC–MS analysis.The particle size of the original salicylic acid particles was L/D: 171/29–34/14 μm/μm. Depending upon the different experimental conditions, smaller particles (L/D: 15.73/4.06 μm/μm) were obtained. The particle size of taxol like white crystal powders was reduced from 0.6–17 μm to 0.3–1.7 μm The results showed that the size of the precipitated salicylic acid and taxol particles were smaller than that of original particles and RESS parameters affect the particle size.  相似文献   

13.
Echinacea species is provided as dietary supplements for various infectious and immune related disorders and has a potential role in cancer prevention. The aim of this study was to optimize the extraction of total flavonoids using different extraction methods and investigate the cytotoxic effects on various cancer cell lines (CaCo-2, MCF-7, A549, U87MG, and HeLa) and VERO (African green monkey) as a non-cancerous cell line. Box-Behnken statistical design was used to evaluate the effect of pressure (100–200 bar), temperature (40–80 °C) and ethanol as co-solvent (6–20 wt%) at a flow rate of 15 g/min for 60 min in supercritical CO2 extraction and the effect of temperature (60–100 °C), time (5–15 min) and power (300–900 W) in microwave-assisted extraction. Optimum extraction conditions were elicited as 300 bar, 80 °C and 13% co-solvent yielding 0.472 mg rutin equivalent total flavonoids/g extract in SC-CO2 extraction, whereas 60 °C, 10 min and 300 W yielded the highest (0.202 mg rutin equivalent) total flavonoids in microwave-assisted extraction. Additional trials with subcritical water (0.022 mg/g) and Soxhlet extraction with methanol (0.238 mg/g) yielded lower flavonoid contents. The exposures upto 50 μg/ml of extracts revealed no significant inhibition on the proliferation of both tested cancer cells and healthy VERO cells.  相似文献   

14.
In this study, the essential oil of aerial parts of a species of a plant called Smyrnium cordifolium Boiss (SCB) was extracted by supercritical CO2. The essence was analyzed by the method of GC/MS. Design of experiments was carried out with response surface methodology by Minitab 16 software to optimize four operating variables of supercritical carbon dioxide (SC-CO2) extraction (pressure, temperature, CO2 flow rate and extraction dynamic time). This is the first report announcing optimization of the operation of supercritical extraction of SCB in laboratorial conditions. Optimizing process was done to achieve maximum yield extraction. Independent variables were dynamic time (td), pressure (P), temperature (T) and flow rate of SC-CO2 (Q) in the range of 30–150 min, 10–30 MPa, 40–60 °C and 0.5–1.7 ml/min, respectively. The experimental optimal recovery of essential oil (0.8431, w/w%) was obtained at 13.43 MPa, 40 °C, 150 min (dynamic) and 1.7 ml/min (CO2 flow rate).  相似文献   

15.
Saponins are surfactants that reduce the surface tension of aqueous solutions, besides having pharmacological actions. In order to extract and fractionate saponins from Pfaffia glomerata roots and Hebanthe eriantha roots using supercritical technology, fractionated extracts were obtained from a sequential process in fixed bed using supercritical CO2 (scCO2), ethanol, and water as solvents. All extractions were carried out in four sequential steps, at 50 °C and 300 bar. In the first step, pure scCO2 was used as solvent, while (a) scCO2/etanol (70:30, w/w); (b) ethanol, and (c) ethanol/water (70:30, v/v) were used as solvents in the three subsequent steps. The extracts were analyzed by thin layer chromatography (TLC) and surface tension. The extraction yields of the four steps were 0.16, 0.55, 1.00, and 6.90% for P. glomerata roots, and 0.17, 0.58, 0.89, and 28% for H. eriantha roots, showing a predominance of high polarity compounds in these species. TLC analysis showed that the extraction process was selective according to the polarity of the solvent, and provided extracts containing different saponins, except for scCO2 extraction. The extracts from the extraction using ethanol + scCO2 (Step 2) showed the greatest ability to reduce the surface tension of water from 72 mN m−1 (pure water) to 25 mN m−1, suggesting that this step was the best for extraction of less polar saponins in the extracts. The critical micelle concentration (CMC) values were approximately 2 and 8 g L−1 for P. glomerata and H. Eriantha, respectively. These results confirmed the efficacy of the extraction process under study.  相似文献   

16.
The use of supercritical carbon dioxide (SC⿿CO2), with water as a modifier, was evaluated in this study as a method to extract protocatechuic acid (PA) from Scutellaria barbata D. Don. The highest extraction yield of PA, 64.094 ± 2.756 μg/g of dry plant, was achieved at 75 °C and 27.5 MPa, with the addition of 15.6% (v/v) water as a modifier. The mean particle size was 0.355 mm, the CO2 flow rate was 2.2 mL/min (STP) and the dynamic extraction time was 100 min. At pressures of 16.2⿿30.0 MPa and temperatures of 45⿿75 °C, the mole fraction solubilities of PA in SC⿿CO2 ranged from 2.829 ÿ 10⿿7 to 9.631 ÿ 10⿿7. The solubility data for PA fit well in the Chrastil model. It is evident that the SC⿿CO2 extraction uses less solvent, saves both energy and time and is an environmentally friendly extract technology that can be used in the food, cosmetic and pharmaceutical industries.  相似文献   

17.
Supercritical carbon dioxide (SC-CO2) extraction of grape marc was studied using water (W) and ethanol (EtOH) as co-solvent at 15% (w/w), 100 and 200 MPa, and 313.15, 323.15 and 333.15 K to analyze their influence upon total phenols of the extracts. The overall extraction curves were determined and suggested 10 MPa and 313.15 K as the best operating conditions for SC-CO2 + 15%W extraction, and 10 MPa and 333.15 K for SC-CO2 + 15% EtOH. The phenolic yields obtained were 63.4 g/kg of extract for SC-CO2 + 15% W and 38.8 g/kg of extract for SC-CO2 + 15% EtOH. An alternative method combining Sc-CO2 + 15% W extraction, followed by SC-CO2 + 15% EtOH was tested. This procedure provided the best results allowing to obtain the highest phenolic yield (68.0 g/kg of extract), phenol content (733.6 mg GAE/100 g DM), proanthocyanidins concentration (572.8 mg catechin/100 g DM) and antioxidant activity (2649.6 mg α-tocopherol/100 g DM). SC-CO2 methods were compared with methanol extraction.  相似文献   

18.
Large-scale supercritical fluid chromatography (SFC) can be used for the purification and concentration of natural samples. The aim of the present work was the concentration of two important antioxidants, mangiferin and quercetin, from mango leaf extracts by using this technique at a pilot plant scale. First of all, the influence of experimental conditions (pressure, temperature, mobile phase composition, isocratic/gradient mode) on the elution profile of the aforementioned compounds and two typical phenolic compounds presented in natural extracts (gallic acid, methyl gallate) was analyzed. The most favorable conditions selected, at the range studied of 10–40 MPa and 40–60 °C, were 40 MPa and 40 °C using as mobile phase the mixture of CO2 + modifier (0.5% formic acid in methanol) in a gradient mode by increasing the concentration of modifier from 5% to 50% (w/w). In a second step, the fractionation of a natural extract obtained by high-pressure extraction was realized. At these conditions, it is possible to multiply the concentration of mangiferin by a factor of five with respect to the original extract.  相似文献   

19.
Supercritical Fluid Extraction (SFE) was used to obtain myrtle leaf extracts, and to study the antioxidant capacity (AOC) and in vitro antimicrobial activity of those extracts. To optimize the SFE operational conditions, the response surface methodology (RSM) was adopted. The parameters studied were: pressure (P), within the range 10 to 30 MPa; temperature (T), between 35 °C and 60 °C and supercritical carbon dioxide (SCCO2) flow rate (Q) within the range 0.15 to 0.45 kg h−1. The results show a good fit to the proposed model and the optimal conditions obtained (23 MPa, 45 °C, and SCCO2 flow rate of 0.3 kg h−1) were within the experimental range. The predicted values agreed with experimental ones, thus indicating the suitability of the RSM model for the optimization of the extraction conditions being investigated. With those values remaining constant, ethanol as a co-solvent was then studied. There was an observed rise in AOC as the amount of ethanol increased, within the range studied (0–30 wt% ethanol). The extract with the highest AOC was tested for its antimicrobial activity against gram-positive and gram-negative bacteria. The minimum inhibitory concentration (MIC) values obtained showed significant inhibitory effect against gram-positive bacteria.  相似文献   

20.
In this study, the extraction of jojoba seed oil obtained from jojoba seed using both supercritical CO2 and supercritical CO2+ethanol mixtures was investigated. The recovery of jojoba seed oil was performed in a green and high-tech separation process. The extraction operating was carried out at operating pressures of 25, 35 and 45 MPa, operating temperatures of 343 and 363 K, supercritical fluid flow rates of 3.33 × 10−8, 6.67 × 10−8 and 13.33 × 10−8 m3 s−1, entrainer concentrations of 2, 4 and 8 vol.%, and average particle diameters of 4.1 × 10−4, 6.1 × 10−4, 8.6 × 10−4 and 1.2 × 10−3 m. It was found that a green chemical modifier such as ethanol could enhance the solubilities, initial extraction rate and extraction yield of jojoba seed oil from the seed matrix as compared to supercritical CO2. In addition, it was found that the solubility, the initial extraction rate and the extraction yield depended on operating pressure and operating temperature, entrainer concentration, average particle size and supercritical solvent flow rate. The solubility of jojoba seed oil and initial extraction rate increased with temperature at the operating pressures of 35 and 45 MPa and decreased with increasing temperature at the operating pressure of 25 MPa. Furthermore, supercritical fluid extraction involved short extraction time and minimal usage of small amounts entrainer to the CO2. About 80% of the total jojoba seed oil was extracted during the constant rate period at the pressure of 35 and 45 MPa.  相似文献   

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