Supercritical CO2 Fluid Extraction Research Articles

Optimization of Supercritical CO2 Fluid Extraction of Flavonoids from Spina Gleditsiae by Response Surface Method

In order to optimize the supercritical CO2 fluid extraction of flavonoids from spina gleditsiae, single-factor experiments were utilized to investigate the influences of the extraction temperature, extraction pressure, and entrainment dosage firstly. Then the optimal extraction process for flavonoids extraction was determined by response surface methodology and the quadratic mathematical model was established which reliability was finally verified. The optimal supercritical CO2 fluid extraction conditions were as follows: entrainment dosage of 36mL, extraction temperature of 48°Cand extraction pressure of 40Mpa. Under this condition, the yield of flavonoids from spina gleditsiae was 0.793%.

Supercritical CO2 fluid extraction of croton crassifolius Geisel root: Chemical composition and anti-proliferative, autophagic, apoptosis-inducing, and related molecular effects on A549 tumour cells

BackgroundThe use of plant essential oils as pharmaceuticals is a fast-growing market especially in China. Throughout the 20th century, a rapid increase took place in the use of many essential oil-derived products in the medicinal industry as nutraceuticals, medicinal supplements, and pharmaceuticals. PurposeThe objective of this study was to explore the chemical composition of Croton crassifolius essential oil as well as its potential anti-tumour properties and related anti-proliferative, autophagic, and apoptosis-inducing effects. MethodsSupercritical CO2 fluid extraction technology was used to extract CCEO and the chemical constituents of the essential oil were identified by comparing the retention indices and mass spectra data taken from the NIST library with those calculated based on the C7-C40 n-alkanes standard. The cytotoxic activity and anti-proliferative effects of CCEO were evaluated against five cancer cell lines and one normal human cell line via CCK-8 assays. In addition, flow cytometry was used to detect cell cycle arrest. The efficacy of CCEO treatments in controlling cancer cell proliferation was assessed by cell cycle analysis, clonal formation assays, RT-qPCR, and western blot analysis. Autophagic and apoptosis-inducing effects of oils and the associated molecular mechanisms were assessed by flow cytometry, cell staining, reactive oxygen species assays, RT-qPCR, and western blot analysis. ConclusionForty compounds representing 92.90% of the total oil were identified in CCEO. The results showed that CCEO exerted a measurable selectivity for cancer cell lines, especially for A549 with the lowest IC50 value of 25.00 ± 1.62 μg/mL. Assessment of the anti-proliferative effects of CCEO on A549 cells showed that the oil inhibited cell proliferation and colony formation in a dose- and time-dependent manner. Investigation of the molecular mechanisms of cell cycle regulation confirmed that the oil arrested A549 cells in G2/M phase by decreasing the expression of cyclin B1-CDK1 and cyclin A-CDK1 and increasing the expression of cyclin-dependent kinase inhibitor (CKI) P21 at both the transcriptional and translational levels. Autophagy staining assays and western blot analysis revealed that CCEO promoted the formation of autophagic vacuoles in A549 cells and increased the expression of autophagy-related proteins beclin-1 and LC3-II in a dose-dependent manner. A series of apoptosis analyses indicated that CCEO induces apoptosis through a mitochondria-mediated intrinsic pathway. This study revealed that CCEO is a promising candidate for development into an anti-tumour drug of the future.

Structured Polyvinyl Alcohol/Zeolite/Carbon Composites Prepared Using Supercritical Fluid Extraction Techniques as Adsorbent for Bioethanol Dehydration

Introduction. Adsorption is a purification process with a more efficient energy level than others. Adsorption performance is strongly influenced by the ability of the adsorbent to be used; therefore, the modification of the adsorbent becomes a very important key for the purification process that occurs. Methods. In this study, the preparation of composite adsorbents was carried out by combining polyvinyl alcohol (PVA), zeolite (Zeo), and activated carbon (AC) as precursors. The crosslinking process was fulfilled by adding glutaraldehyde to the precursor mixtures followed by a supercritical fluid CO2 extraction (SFE) technique to create conditions for the crosslinking process. The composites were analyzed using Braunner–Emmet–Teller (BET) surface area analysis, Fourier-transform infrared (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy with energy dispersive X-ray (SEM/EDX-mapping), while individual and composite adsorbents were evaluated for their ability in bioethanol dehydration at various initial concentrations of ethanol and temperature. Results. The BET characterization shows that composite preparation under supercritical CO2 conditions provides reasonable surface areas, which are proportional to the content of activated carbon. The crosslinking process has been described by FTIR data interpretation, showing that PVA and glutaraldehyde were properly distributed on Zeo and AC precursors. The DSC characterization results give information that PVA successfully forms hydrophilic composites within Zeo and AC. The SEM micrograph analysis shows the formation of pores on the surface and cross section in structured adsorbents. The experimental adsorption shows that an increasing amount of AC in the composites increases the capacity of water adsorption (i.e., 0.80 gram of water/gram of adsorbent for PVA/Zeo/AC = 1 : 1 : 1 at 22°C). However, the effect is not significant when the ratio of AC is less than 0.5. As expected, the lower temperature increases the adsorption capacity. Further, by using approximately 4.5 gram adsorbents composite in 30 ml of water-ethanol mixtures, high concentration of bioethanol (>99%) can be achieved at various temperatures from 22°C to 40°C and bioethanol initial concentration from 88% to 96%. Conclusion. The SFE technique provides distinguished adsorbents composite properties. Further, the new composites provide about four times better adsorption capacity than that showed in the individual adsorbents test. The addition of AC influences on increasing the capacity and adsorption kinetics value.

A kinetic Model of Flavonoid from Spina Gleditsiae by Supercritical CO2 Fluid Extraction

A kinetic model of flavonoid from spina gleditsiae by supercritical CO2 fluid extraction was developed by an adsorption-desorption equilibrium model. Extraction kinetic curves were fitted by origin mathematical software, and then used for prediction and experimental verification. The results showed that the prediction were consistent with the experimental process. This model illustrates solution-mass transfer mechanism of flavonoid from spina gleditsiae in supercritical extraction process, and has the advantage not only for better precision it offers, but also for the fact that it only requires moderate experimental conditions.

Extraction of Astaxanthin and Lutein from Microalga Haematococcus pluvialis in the Red Phase Using CO₂ Supercritical Fluid Extraction Technology with Ethanol as Co-Solvent.

Astaxanthin and lutein, antioxidants used in nutraceutics and cosmetics, can be extracted from several microalgal species. In this work, investigations on astaxanthin and lutein extraction from Haematococcus pluvialis (H. pluvialis) in the red phase were carried out by means of the supercritical fluid extraction (SFE) technique, in which CO2 supercritical fluid was used as the extracting solvent with ethanol as the co-solvent. The experimental activity was performed using a bench-scale reactor in semi-batch configuration with varying extraction times (20, 40, 60, and 80 min), temperatures (50, 65, and 80 °C) and pressures (100, 400, and 550 bar). Moreover, the performance of CO2 SFE with ethanol was compared to that without ethanol. The results show that the highest astaxanthin and lutein recoveries were found at 65 °C and 550 bar, with ~18.5 mg/g dry weight (~92%) astaxanthin and ~7.15 mg/g dry weight (~93%) lutein. The highest astaxanthin purity and the highest lutein purity were found at 80 °C and 400 bar, and at 65 °C and 550 bar, respectively.

Optimization of Supercritical CO2 Fluid Extraction Conditions of Saponins from Spina Gleditsiae

In this work, saponins were extracted from spina gleditsiae by supercritical CO2 fluid extraction. The effects of extraction pressure, extraction temperature, extraction time, entrainment dosage and entrainment concentration on extraction process were studied. The optimum conditions for extraction were as follows: extraction pressure as 35MPa, extraction temperature as 45°C, extraction time as 2.5h, the ratio of materials/entrainment (g/mL) as 1:3.0, entrainment concentration as 70%. Under these conditions, saponins yield was 0.975%.

Optimization of Supercritical CO2 Fluid Extraction Conditions of Flavonoids from Spina Gleditsiae

In this work, supercritical CO2 fluid extraction method was used to extract the flavonoids from spina gleditsiae. we investigated the influence of four factors, namely entrainment dosage, extractive temperature, extractive pressure, and extractive time on the extraction of flavonoids. The optimum process conditions for the extraction were as follows: entrainment dosage of 37.5mL, extractive temperature of 45°C, extractive pressure of 40Mpa, extractive time of 1.0h. The actual yield of flavonoids was 1.112%, which was close to the theoretical value of 1.116%.

Supercritical fluid CO2 extraction of thorium from "black" sands of the Azov sea

Supercritical fluid CO2 extraction of thorium from "black" sands of the Azov sea

LIGNANS IN OLIVE STONES DISCARDED FROM THE OIL INDUSTRY. COMPARISON OF THREE EXTRACTION METHODS FOLLOWED BY HPLC-DAD-MS/MS AND ANTIOXIDANT CAPACITY DETERMINATION

Lignans are secondary metabolites with diverse chemical structure, and are frequent in food grains. A lignan rich diet have a positive health impact over chronic diseases and protection against certain types of cancer. To enhance the intake of lignans the addition of this compound in processed food could be a solution, so the best approach is to find a source of lignans, especially one that is discarded as waste. In the olive oil production there is a large volume of phytotoxic waste generated, among these is the olive stone (OS), that it is generally burned for fuel. It has been reported the presence of lignans in olive stones extracted with methanol reflux. Three extraction methods for lignans and polyphenolic compounds were assessed: solid-liquid ultrasound assisted extraction with basic hydrolysis, methanolic extraction with Soxhlet, and CO2 supercritical fluid extraction with methanol as a modifier. The determination of lignan content in OS samples were evaluated by HPLC with a core shell C18 column and the detection was in tandem with DAD and MS/MS. The extracts were also evaluated in their antioxidant capacity with ABTS, CUPRAC and ORAC assays and total polyphenol concentration. The aim of this work is to evaluate different methods to extract lignans from OS discarded from the olive oil industry. The main lignan identified in OS extract was pinoresinol. The SFE method to extract pinoresinol was more efficient than Soxhlet and ultrasound assisted solid liquid extractions, producing a higher amount of pinoresinol in the extract in less time and with less amount of co-extracted interferents. The extract produced with Soxhlet had a higher antioxidant capacity.

Optimization on Supercritical CO<sub>2</sub> Extraction Process to Improve the Quality of Patchouli Oil by Response Surface Methodology Approach

Until now, the patchouli oil is the largest commodity export of essential oil for Indonesia. But the price of patchouli oil is often unstable due to the quality of oil which fluctuates depending on the components. To improve the performance and quality of patchouli oil had been carried out the purification process using supercritical CO2 fluid extraction method. Optimization conditions of the extraction process using the approach of Response Surface Methodology (RSM) and the influence of independent variables include temperature (35–45 °C), pressure (80–150 atm) and the time of extraction (60–300 min), and then evaluated using a Box-Behnken Design (BBD). Analysis of the components in the extract was carried out by using GC-MS and GC-FID to detect the changes of compositions of the components containing the oil before and after the extraction process. The optimum condition of supercritical extraction within experimental range of the studied variables was at 38 °C, 146.35 atm and 74 min for predicted oil yield of 6.41% and at 41.45 °C, 135.17 atm and 252.62 min and the predicted patchouli alcohol content was 25.34%. The extracted oil is enriched with the main components such as patchouli alcohol compared to the original patchouli oil. The results of RSM evaluation showed consistency between the variables contained in the experiment and the prediction.

Optimization for extraction of an oil recipe consisting of white pepper, long pepper, cinnamon, saffron, and myrrh by supercritical carbon dioxide and the protective effects against oxygen–glucose deprivation in PC12 cells

This study is to investigate the most efficient extractives of extracting oil recipe for stroke treatment and the protective effects on an oxygen and glucose deprivation model in PC12 cells. An orthogonal experimental design L9 (34) was carried out for oil recipe's optimization with supercritical CO2 fluid extraction. 2-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and enzyme-linked immunosorbent assay were conducted to evaluate cell activity and indexes in the cell lysate. The result showed that the optimum extraction condition was 30Mpa, 50°C, 100min, the extracts were analyzed by gas chromatography–mass spectrometry and among forty detected compounds 27 were identified, representing 80.86% of the total oil content. trans-Cinnamaldehyde (14.14%), piperine (9.32%), β-amyrin (6.79%), lupenone (6.28%), longifolene (6.07%), β-caryophyllene (5.21%), α-bisabolol (4.11%), and β-bisabolene (2.56%) were high mass fraction. Oil recipe could significantly attenuate PC12 cell damage, the lactate dehydrogenase release and decreased the malondialdehyde levels, glutathione peroxidase and nicotinamide adenine dinucleotide phosphate oxidase activity, glutathione and nitric oxide content (p<0.01) and increased the level of superoxide dismutase after oxygen and glucose deprivation. The protective mechanism may be related to oil recipe's antioxidant effect by scavenging free radicals.

Investigation on Stripping-down TNT from Waste Munitions by Supercritical CO2 Fluid Extraction under Low Temperature Conditions

Investigation on Stripping-down TNT from Waste Munitions by Supercritical CO2 Fluid Extraction under Low Temperature Conditions

Composition, Antimicrobial and Antioxidant Activity of Supercritical Fluid Extract of Elsholtzia ciliata

Elsholtzia ciliate is mainly used in folk medicine for the treatment of cold, fever, dysentery and digestion disorder. The aim of our study is to investigate the composition of supercritical fluid extract of Elsholtzia ciliate and to study its antimicrobial and antioxidant activity. In our research, the extract of Elsholtzia ciliate was extracted using the CO2 supercritical fluid extraction (SFE) and then its chemical constituents were analyzed by gas chromatography-mass spectrometry (GC-MS). Seventeen components were identified by GC-MS analysis which mainly include elsholtzia ketone (9.16 %), 9,12,15-octadecatrienoic acidethyl ester (13.74 %), 9,12-octadecadienoic acid (13.59 %), tetratriacontane (11.25 %), and octacosane (9.49 %). A good antibacterial effect of the extract has been proved by an experiment performed in an antibacterial assay with minimum inhibitory concentration (MIC) values and inhibition zone. Moreover, the extract showed low levels of antioxidant capacity in the DPPH assay, as well as slight inhibitory activity in a β-carotene bleaching assay. The results of this research show that the extracts of Elsholtzia ciliata might be a natural potential source of food preservatives and antioxidants.

Chemical composition, in vitro anti-tumor activities and related mechanisms of the essential oil from the roots of Potentilla discolor

Potentilla discolor has been used as the Traditional Chinese Medicine ingredient in prescription for over 400 years, and scientific evidences have confirmed its effectiveness as an anticancer agent. The present study is undertaken to assess, for the first time, the chemical composition, potential in vitro anti-tumor activities and related mechanisms of the essential oil, which was extracted from Potentilla discolor fresh roots by supercritical CO2 fluid extraction technology. Twenty-nine compositions were identified by gas chromatography-mass spectrometry. The anti-tumor activity of the essential oil was screened against four cancer cell lines and the lowest IC50 value was 19.02 μg/mL on T24 cell line. Then, T24 was selected as a representative cell line for the related mechanism research. As a result, cell cycle assay confirmed that the cell growth was inhibited by Potentilla discolor essential oil and cell cycle was arrested in DNA synthesis phase. A series of apoptosis analysis indicated that Potentilla discolor essential oil induced apoptosis through mitochondrion-mediated intrinsic pathway. This study revealed that Potentilla discolor essential oil has significant anti-tumor activity. It should be useful in the search for new potential anti-tumor agents and pharmaceutical industries.

Antibacterial activity of Artemisia asiatica essential oil against some common respiratory infection causing bacterial strains and its mechanism of action in Haemophilus influenzae

The main objective of the current study was to investigate the chemical composition of the essential oil of Artemisia asiatica together with investigating the antibacterial effects it exerts on several common respiratory infection causing bacteria including Haemophilus influenzae. Its mechanism of action was studied using various state-of-the-art assays like scanning electron microscopy, DNA, RNA and protein leakage assays, growth curve assays etc. The essential oil was extracted from the leaves of A. asiatica by supercritical CO2 fluid extraction technology. Chemical composition of essential oils was analyzed by gas chromatography-mass-spectrometry (GC-MS). The antibacterial activity was evaluated against 6 bacteria by the paper disc diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC) values of the essential oil were estimated by agar dilution method. The antibacterial mechanism was evaluated by growth curve, the integrity of cell membrane and scanning electronmicroscope (SEM). Gas chromatographic analysis of the A. asiatica essential oil led to the identification of 16 chemical constituents accounting for 97.2% of the total oil composition. The major components were found to be Piperitone, (z)-davanone, p-cymene and 1, 8-cineole. The essential oil showed maximum growth inhibition against Haemophilus influenzae with a zone of inhibition of 24.5 mm and MIC/MBC values of 1.9/4.5 mg/mL respectively. Bacteria treated with the essential oil led to a rapid decrease in the number of viable cells. On adding the essential oil of A. asiatica to the bacterial culture, the constituents of the bacterial cell got released into the medium and this cell constituent release increased with increasing doses of the essential oil. SEM showed that the bacterial cells treated with the essential oil showed damaged cell wall, deformed cell morphology and shrunken cells.

Aroma Components from Baked Soybean Oil Extracted by CO2 Supercritical Fluid Extraction

Baked soybean oil has desired aroma which is loved by most of people. Soybean oil is one of most important vegetable oils consumed in the world. Analysis of aroma components from Baked Soybean Oil extracted by CO2 Supercritical Fluid Extraction (SFE-BSO) was performed by Gas Chromatography-Mass Spectrometry (GC-MS). The aroma components of SFE-BSO were extracted by Simultaneous Distillation Extraction (SDE). Thirty four aroma compounds in SFE-BSO were identified. 3-Methyl-1-butanol and other eleven compounds were the key aroma compounds of SFE-BSO, which were analyzed by GC-Sniffing technique.

Erratum: Evaluation of Cannabinoid and Terpenoid Content: Cannabis Flower Compared to Supercritical CO2 Concentrate.

A recent cannabis use survey revealed that 60% of cannabis users rely on smelling the flower to select their cannabis. Olfactory indicators in plants include volatile compounds, principally represented by the terpenoid fraction. Currently, medicinal- and adult-use cannabis is marketed in the United States with relatively little differentiation between products other than by a common name, association with a species type, and Δ-9 tetrahydrocannabinol/cannabidiol potency. Because of this practice, how terpenoid compositions may change during an extraction process is widely overlooked. Here we report on a comparative study of terpenoid and cannabinoid potencies of flower and supercritical fluid CO2 (SC-CO2) extract from six cannabis chemovars grown in Washington State. To enable this comparison, we employed a validated high-performance liquid chromatography/diode array detector methodology for quantification of seven cannabinoids and developed an internal gas chromatography-mass spectrometry method for quantification of 42 terpenes. The relative potencies of terpenoids and cannabinoids in flower versus concentrate were significantly different. Cannabinoid potency increased by factors of 3.2 for Δ-9 tetrahydrocannabinol and 4.0 for cannabidiol in concentrates compared to flower. Monoterpenes were lost in the extraction process; a ketone increased by 2.2; an ether by 2.7; monoterpene alcohols by 5.3, 7 and 9.4; and sesquiterpenes by 5.1, 4.2, 7.7, and 8.9. Our results demonstrate that the product of SC-CO2 extraction may have a significantly different chemotypic fingerprint from that of cannabis flower. These results highlight the need for more complete characterization of cannabis and associated products, beyond cannabinoid content, in order to further understand health-related consequences of inhaling or ingesting concentrated forms.

CO2 supercritical fluid extraction and characterization of polysaccharide from bamboo (Phyllostachys heterocycla) leaves

CO2 supercritical fluid technique with an ethanol modifier was used to extract bamboo (Phyllostachys heterocycla) leave’s polysaccharide (BLPs) regarding various operating conditions. Pressure (30, 40 and 50 MPa), extraction temperature (40, 45 and 50 °C), extraction time (2, 3 and 4 h) and modifier dosage (20, 25 and 30 mL) were important operating factors affecting the yield and total antioxidant activity of each BLPs extraction. The optimal parameters for harvesting the BLPs were an extracting time of 2 h plus 40 MPa pressure with 30 mL of ethanol modifier at 50 °C. In this case, 2.47% BLPs (in wt) was extracted. The BLPs, after purified by D101 macroporous resin and DEAE-cellulose column, with the average molecular weight of 5.05 × 104 Da are composed of rhamnose, fucose, arabinose, xylose, mannose, glucose, and galactose in the molar ratio of 1.318:2.100:1.189:1.016:1:4.776:1.318, respectively. It showed the best antioxidant activity, and its total antioxidant activity of the BLPs extracted was equivalent to 20.70 mg ascorbic acid [(VcE)/g]. In a word, our technique should be potential for producing the best yield and activity of bamboo (Phyllostachys heterocycla) leave’s polysaccharide.

Chemical Composition and Antimigraine Activity of Essential Oil of Angelicae dahuricae Radix.

The aim of this study was to explore the chemical composition and the effect of essential oil of Angelicae dahuricae radix on a nitroglycerin (NTG)-induced rat model of migraine. The CO2 supercritical fluid extraction method was optimized for the extraction of essential oil of A. dahuricae radix (EOAD) and its chemical composition was determined. The migraine model was established by subcutaneous injection of NTG (10 mg/kg) 1 h after the last administration of EOAD. The therapeutic effect of EOAD and its underlying mechanism were assessed by monitoring behavioral changes, levels of nitric oxide (NO) in serum and brain tissues, plasma levels of calcitonin gene-related peptide (CGRP) and endothelin (ET), and ET/NO ratio. The optimal conditions for CO2 supercritical fluid extraction of EOAD, as determined by orthogonal test [L9(34)], were as follows: 2 h extraction time, 20 MPa pressure, 40°C temperature, and 30 mesh. The yield of EOAD was 1.8%. On gas chromatography-mass spectrometry, 45 peaks were found in EOAD, and 22 compounds were identified and quantified. The main constituents of EOAD were 1-dodecanol (13.71%), elemene (7.54%), palmitic acid ethyl ester (7.32%), α-pinene (6.25%), and 1-pentadecanol (6.08%). Compared with rat migraine model controls, EOAD (35, 70, and 140 mg/kg) significantly reduced the number of head shaking, head scratching, and hind leg shooting events, decreased serum and brain NO levels, decreased plasma CGRP, and increased ET levels in rats. ET/NO ratio was elevated to 28.68 in the EOAD high-dose group. EOAD ameliorates NTG-induced migraine in rats likely by modulating the levels of vasoactive substances.

Poly(lactic acid) foams reinforced with cellulose micro and nanofibers and foamed by chemical blowing agents

Biodegradable polymeric foams have gained increasing attention as an alternative to conventional polymeric foams, whose recycling is economically unviable due to its low density. Based on this, this article discusses the development of poly(lactic acid) foams produced with the insertion of four and eight parts hundred resin (phr) of long and short cellulose fibers and nanofibers. Short fibers of nanocellulose were obtained by mechanical defibrillation and dried by lyophilization, and long fibers by CO2 supercritical fluid extraction. The poly(lactic acid) foams were produced by adding a chemical blowing agent with a pressure-free expansion method. In general, short fibers of cellulose act as nucleating agents during the expansion of the foam, which is observed by its greater number of smaller-size cells than the non-reinforced poly(lactic acid) foams. The insertion of long fibers of cellulose restricts the mobility of the polymer matrix during the expansion, thus hindering the foam its growth and formation of bubbles.