Supercritical Fluid Extraction Conditions Research Articles

An efficient, green, and easy-to-scale-up strategy for target-oriented isolating cadinene sesquiterpenoids from Eupatorium adenophorum Spreng.

A green and efficient strategy was established and optimized for target-oriented extraction, enrichment and separation of cadinene sesquiterpenoids from Eupatorium adenophorum Spreng., using the combination of supercritical fluid extraction, molecular distillation, and industrial preparative chromatography for the first time. The extraction conditions of supercritical fluid extraction were initially optimized by orthogonal experimental design. Under the optimum conditions, the contents of 9-oxo-10,11-dehydroageraphorone and 10Hβ-9-oxo-ageraphorone, which were 55.00% and 6.01%, respectively, were much higher than conventional extraction methods. Then, the molecular distillation enrichment method was established and investigated by response surface methodology technology, which showed strong specificity for enriching target compounds and removing impurities from crude extracts. Under the optimum conditions of molecular distillation, total contents of cadinene sesquiterpenoids were increased to 89.19%. Finally, a total of 146mg of 9-oxo-10,11-dehydroageraphorone and 29mg of 10Hβ-9-oxo-ageraphorone were easily obtained by industrial preparative chromatography, from 200mg of distillation fraction, with purities over 99%. The contents of target components were analyzed by HPLC, and structures of them were identified by high-resolution MS, 1 H-NMR, and 13 C-NMR spectroscopy. These results indicate that it is a simple, effective, and eco-friendly strategy, which is easily converted into industrial scale.

Optimization of Supercritical Fluid Extraction of Paprika (cv. Reshampatti) Oil, Capsaicin and Pigments

AbstractPaprika (Capsicum annuum L.) is a spice, utilized in culinary across the globe for its colour and pungency. A study was conducted to optimize the supercritical fluid extraction (SFE) process individually for selective extraction of paprika oil, capsaicin and pigments. Paprika oil was extracted by supercritical fluid—carbon dioxide at different process parameters: temperature (35‐75°C), pressure (100‐500 bar), extraction time (60‐180 minutes) and particle size (0.25‐1.25 mm) using central composite rotatable design (CCRD). The ANOVA results showed that yields of paprika oil, capsaicin and pigments were significantly (P ≤ .05) affected by the extraction process variables. Optimized SFE conditions, 65, 65 and 57.04°C temperature; 357.8, 200.62 and 400 bar pressure; 90, 90 and 100.89 minutes extraction time; and 0.78, 0.50 and 0.89 mm particle size, were obtained for optimum yield of paprika oil, capsaicin and pigments, respectively. Experimental yield of paprika oil, capsaicin and pigments at the optimized condition for respective compounds was 4.91% (w/w), 2.10% (w/w) and 16 319.9 NCV, and had good agreement with the predicted values. Antimicrobial activity of extracted paprika oil was found against E. coli, B. subtilus and S. aureus.

Supercritical fluid extraction (SFE) optimization of trans-resveratrol from peanut kernels (Arachis hypogaea) by experimental design.

The aim of this study was to develop the optimal conditions for supercritical fluid extraction (SFE) of bioactive trans-resveratrol from peanut kernels using an experimental design. The variables taken into account were extraction pressure, extraction temperature, extraction time and amount of modifier. The model was first set for significant factor screening by full factorial design, then, optimized by central composite designs. The optimal extraction parameters were a pressure of 7000psi, temperature of 70°C and time of 50min while amount of modifier did not show significant effect. The quantity of trans-resveratrol was predictable by a full quadratic regression equation with R2(predict) = 95.56%. The predicted trans-resveratrol concentration in peanut samples was 0.7998µg/g while the experimental concentration was 0.7884 ± 0.1553µg/g. Conventional solvent extraction demonstrated less selectivity and needed more clean-up process prior to HPLC analysis. Our optimized SFE condition was effective to maximize trans-resveratrol extraction with less contaminants and gave the comparable amount of trans-resveratrol between actual and predicted values.

Supercritical fluid extraction of Arbutus unedo distillate residues – Impact of process conditions on antiproliferative response of extracts

The strawberry tree (Arbutus unedo) is an evergreen plant belonging to the Ericaceae family, an endemic specie of the Mediterranean. In Portugal it grows mostly wild and its fruits are mainly used to produce a distillated alcoholic beverage called “Aguardente de Medronho”. From the process, a residue is obtained which is normally discarded, despite it may figure as biomass for valorization.This work intends to study different conditions of supercritical fluid extraction (SFE), using carbon dioxide as solvent and ethanol as co-solvent for the recovery of bioactive compounds from that residue. After a screening design of experiments varying pressure, temperature, co-solvent, flow rate and time of extraction, an optimization design of experiments (central composite design) was performed. Time (90 min) and flow rate (10 g/min) were established. Variables were pressure (100, 200 and 300 bar), temperature (35, 45 and 55 °C) and co-solvent concentration (0, 10 and 20 %). Extracts were analyzed by GC–MS and LC–MS/MS and cytotoxicity and antiproliferative effect of the extracts was evaluated in Caco2 and HT-29 cell models respectively. Chemical characterization showed an increase in phenolic compounds such as pyrogallol, gallic acid, catechol and protocatechuic acid amongst others, with the increase of the co-solvent. GC–MS analysis revealed a diversity of compounds from fatty acid esters, terpenes and small molecules with recognized bioactivity. The most promising extract was obtained using 300 bar and 55 °C and 20 % of co-solvent. Besides being the extract with the highest yield, it also presented the lowest EC50 (0.569 mg/mL) mainly due to the presence of phenolic compounds.

Determination of lipid mediators in breast cancer cells using lyophilization-supercritical fluid extraction online coupled with supercritical fluid chromatography-quadrupole tandem mass spectrometry.

A lyophilization-supercritical fluid extraction coupled with supercritical fluid chromatography-quadrupole tandem mass spectrometry online method was developed for the determination of lipid mediators in breast cancer cells. Supercritical fluid extraction was applied to the cell samples for the first time due to the use of lyophilization. The conditions of supercritical fluid extraction and supercritical fluid chromatography-quadrupole tandem mass spectrometry were investigated systematically. Under the optimized conditions, all the calibration curves for the lipid mediators showed good linearity (correlation coefficient>0.99). The limits of detection and the limits of quantification were in the range of 0.190-5.36pg and 0.560-16.2pg, respectively. The recoveries were in the range of 70.3-125%. The relative standard deviations of the precision ranged from 1.49-18.7% and the accuracies were higher than 84%. Compared with liquid-liquid extraction coupled with liquid chromatography and tandem mass spectrometry method, the present approach reduced the manual labor and obtained higher sensitivity as well as higher extraction recoveries for all 15 lipid mediators. Finally, the online method was applied to the quantification of lipid mediators in breast cancer cells and normal mammary epithelial cells. On the basis of the results, this lyophilization-supercritical fluid extraction online coupled with supercritical fluid chromatography-quadrupole tandem mass spectrometry method showed great promise in the analysis of lipid mediators in complex biological samples.

Selective extraction of phospholipids from whey protein phospholipid concentrate using supercritical carbon dioxide and ethanol as a co-solvent

In recent years, using dairy phospholipids (PL) as functional ingredients has increased because PL have nutritional benefits and functional properties. In this study, a novel 2-step supercritical fluid extraction (SFE) process was used to extract whey protein phospholipid concentrate (WPPC), a dairy co-product obtained during the manufacture of whey protein isolate, for PL enrichment. In the first step, nonpolar lipids in WPPC were removed using neat supercritical carbon dioxide (S-CO2) at 41.4 MPa and 60°C. In the second stage, the feasibility of using the polar solvent ethanol as a co-solvent to increase the solubility of S-CO2 extraction solvent was explored. A 3 × 3 × 2 factorial design with extraction pressure (35.0, 41.4, and 55.0 MPa), temperature (40 and 60°C), and concentration of ethanol (10, 15, and 20%) as independent factors was used to evaluate the extraction efficiency providing the most total PL, and the best proportion of each individual PL from the spent solids collected during S-CO2 SFE. All lipid fractions were analyzed using thin-layer chromatography and high-performance lipid chromatography. The total amount of PL extracted from WPPC was significantly affected by ethanol concentration; the extraction pressure and temperature were nonsignificant. The optimal SFE condition for generating a concentrated PL lipid fraction was 35.0 MPa, 40°C, and 15% ethanol concentration; the highest amount of extracted PL averaged 26.26 g/100 g of fat. Moreover, adjusting SFE condition allowed successful recovery of a high concentration of sphingomyelin, phosphatidylcholine, and phosphatidylethanolamine, giving averages of 11.07, 10.07, and 7.2 g/100 g of fat, respectively, 2 to 3 times more than conventional solvent extraction. In addition, exhausted solids obtained after the SFE process were enriched with denatured proteins (72% on dry basis) with significantly more water-holding capacity and emulsifying capacity than untreated WPPC. Overall, this 2-stage SFE process using neat S-CO2 and ethanol has the greatest potential to produce a PL-rich lipid fraction from WPPC.

Exploration and optimization of conditions for quantitative analysis of lignans in Schisandra chinensis by an online supercritical fluid extraction with supercritical fluid chromatography system

An online supercritical fluid extraction with supercritical fluid chromatography system could provide sequential extraction and quantitative analysis of lignans in Schisandra chinensis. Supercritical fluid extraction conditions were optimized at 15MPa, 50°C, and 4min with supercritical CO2 adding 1% methanol; the elution volume and flow rate were set at 6mL and 2mL/min to blow extract out of the tank completely. The split-flow rate was confirmed at 2.5%, which determines injection volume and accuracy of quantitative detection. The factors having negative influences on supercritical fluid chromatography retention in the online system, including sample loading forms and backpressure settings, are discussed in the paper. At last, an extraction-quantitative method for lignans in Schisandra chinensis was developed, which could be finished within 19.5min. The total content percentage of four lignans (Schisandrin, Schisandrin A, Schisandrin B and Schisandrol B) in four batches was respectively measured to be 1.42, 1.54, 1.62, and 1.90%.

Yield Optimization and Supercritical CO<sub>2</sub> Extraction of Essential Oil from Jasmine Flower

Supercritical fluid extraction (SFE) is an innovation that permits extraction of an extensive variety of different chemical composition from the plant grids. Extraction of essential oil from Jasmine flower was tentatively carried out using the supercritical CO2 technique. The effect of extraction parameters which include pressure (100–300 bar) and temperature (300–350 K) on the oil recovery was explored. The extraction process was optimized using the response surface methodology (RSM). At the SFE optimal conditions, the chemical compositions of the extracted oil were examined using gas chromatography-mass spectrometry (GC-MS) analysis. The obtained result reflected that the optimal yield of oil from Jasmine flower was 12.18% mg oil extracted/100 g dry flower, which was achieved through an SFE optimal conditions of pressure at 200 bar and extraction temperature at 325 K. A total number of six chemical compounds were tentatively identified in the Jasmine flower extracted oil at the optimal SFE conditions.

Supercritical Fluid Extraction of Carotenoids from Vegetable Waste Matrices.

The aim of this work was to evaluate a previously-developed model on supercritical fluid extraction (SFE) for carotenoid recovery from carrot peels on various carotenoid-rich fruit and vegetable wastes. To this end, 15 matrices, including flesh and peels of sweet potato, tomato, apricot, pumpkin and peach, as well as flesh and wastes of green, yellow and red peppers, were submitted to SFE under optimised conditions (59 °C, 350 bar, 15 g/min CO2, 15.5% (v/v) ethanol as co-solvent, 30 min of extraction time). The obtained extracts were characterised for their total carotenoid content, antioxidant activity and total carotenoid recovery (TCR). TCR values were greater than 90% w/w for most samples, with β-carotene being the most successfully extracted compound (TCRs 88–100% w/w). More polar carotenoids, such as lutein and lycopene, exhibited lower TCRs. A comparison with literature data suggested that carotenoid extraction is partially dependent on the composition of vegetable matrices, specifically on polysaccharide and moisture content. The results indicated that the optimised SFE conditions can be used as a general model for carotenoid extraction from various fruit and vegetable matrices and as a viable method for adding value to these waste streams by generating carotenoid-rich extracts.

Supercritical carbon dioxide extraction of Solidago gigantea Ait.: Optimization at quarter-technical scale and scale up the process to half-technical plant

Solidago gigantea Ait. (goldenrod) is widely spread in Poland and has a traditional usage as medicinal plant due to the content of bioactive compounds. The main aims of this research were to obtain the optimal conditions of supercritical fluid extraction (SFE) of S. gigantea with carbon dioxide as a solvent in the quarter-technical plant and to scale-up the process to half-technical, where both works in a high range of pressure - up to 100 MPa. Response surface methodology (RSM) was used to analyze and evaluate the influence of process parameters: pressure (P, MPa), temperature (T, K) and solvent flow rate (F, kg h−1) on output variables. The selected output variables were yield, total phenolics content, total chlorophylls content and lipids content. The optimal parameters obtained at quarter-technical plant, for a chosen response – yield, were: T = 353.15 K (80 °C), P = 72.31 MPa and F = 6.97 kg h−1. Scale-up extractions were conducted according to various criteria at half-technical plant under optimal conditions. Extraction with simultaneously constant ratio of the solvent flow rate to the mass of the feedstock (Q CO2/M, kg h−1 kg−1) and a constant ratio of solvent mass to mass of the batch (S CO2/M, kg kg−1) ended with the best results: mass of obtained extract was 0.311 kg (7.17% DM – dry matter). Analysis of biological properties of the obtained product showed that it exhibits antibacterial activity and very low level of cytotoxicity and therefore, it can be safely used in pharmaceutical and cosmetics formulations.

RECEIVING OIL FROM CLOUDBERRIES FRUITS BY SUPERCRITICAL CARBON DIOXIDE EXTRACTION

Comparative researches of ways of oil extraction from the fulfilled fruits of cloudberries (Rubus chamaemorus) with application of hexane and supercritical carbon dioxide as solvents are executed. Optimization is performed and optimum conditions of supercritical fluid extraction of oil are defined with use of central composite design of 2nd order. Pressure of carbon dioxide of 350 atm, temperature 85 °C, duration of extraction of 80 min are the optimum conditions of carrying out of the process. The yield of oil is 9.0%. Quality key indicators of the received oil were defined. The difference between the oil received by the SKF-CO2 method and the oil received by hexane extraction consists in improvement of organoleptic properties, the raised share of the combined fatty acids at decrease of a share of the free acids and high content of unsaturated fatty acids. It is shown that supercritical carbon dioxide can be an alternative to the hydrocarbons which are traditionally used for these purposes.

Optimization of Supercritical Fluid Extraction of Phenolic Compounds from Peach Blossom (Amygdalus Persica) by Response Surface Methodology

Supercritical fluid extraction (SFE) was used for the extraction of phenolic compounds from peach blossom (Amygdalus persica). The optimum conditions of SFE were optimized by response surface methodology and confirmed at 64°C, 30 MPa, 143 min, and 35 mL ethanol (100%) as modifier for maximum total phenolic contents (54.10 mg GAE g−1 DW), which was higher than the yield achieved by ultrasonic-assisted extraction (44.04 mg GAE g−1 DW). The antioxidant activities and tyrosinase inhibitory activities of extraction extracted by SFE were 79.55% and 14.42%. Furthermore, chlorogenic acid, quercetin-3-O-galactoside, kaempferol-3-O-galactoside, quercitrin-3-O-rhamnoside, and kaempferol 4′-glucoside were identified in this study.

Supercritical fluid extraction of coriander seeds: Kinetics modelling and ANN optimization

The main goal of this research was mathematical modelling and numerical simulation of the supercritical fluid extraction (SFE) process of coriander (Coriandrum sativum L.) seeds. SFE was performed at different set of process parameters: pressure (100, 150 and 200bar), temperature (40, 55 and 70°C) and CO2 flow rate (0.2, 0.3 and 0.4kg/h). Both applied empirical models, derived from models developed by Brunner and Esquivel et al., adequately described SFE process. Second objective was to determine effects of investigated SFE parameters on total extraction yield. Furthermore, calculated parameters from the empirical models were used for the calculation of initial slope, which was successfully used for optimization using artificial neural network (ANN). Optimized SFE conditions for maximized initial slope, i.e. initial rate of the solubility-controlled extraction phase, were pressure of 200bar, temperature of 40°C and CO2 flow rate of 0.4kg/h.

Research on the Selection of Supercritical Fluid Extraction Conditions and Antioxidation of Hawthorn Oil

Hawthorn oil has been shown to own many health benefits, such as being used as a folk medicine. However, the oxidation resistance presented in hawthorn fruit has not been clearly characterized. In order to promote the researches on hawthorn oil, we explored the selection of supercritical fluid extraction conditions and antioxidation of hawthorn oil. To begin with, we detected that the order of impact among four factors of supercritical CO2 extraction was: material degree > resolving temperature > extraction temperature > extraction pressure. In addition, using material degree as 40 mesh to 60 mesh, resolving temperature as 55 °C, extraction temperature as 45 °C, extraction pressure as 25 MPa could obtain the highest extraction yield, namely 2.13%. Meanwhile, we explored antioxidation of hawthorn oil on plant and animal oil. Hawthorn oil showed some effect in stabilizing plant and animal oil. Additionally, it could generate synergistic effect with citric acid, ascorbic acid and butylated hydroxytoluene during antioxidation process in plant and animal oil.

Efficient extraction and purification of flexibilane and tigliane diterpenoids from Stillingia lineata using sequential SFE-CO2 and SFC-CO2

Quite a number of methods of extraction and separation are currently used to isolate and purify secondary metabolites from complex mixtures, but "green" technologies are still far from being used routinely in public research laboratories. In recent years, supercritical fluid extraction (SFE) and chromatography (SFC) have gained increasing interest in production of high-value plant extracts for pharmaceutical, cosmetic and food industries. SFC enables fast and reliable separation of biomolecules from complex mixtures [1,2]. Supercritical carbon dioxide (SC-CO2) is an eco-friendly, chemically inert, nontoxic and noninflammable fluid. As a green material, SC-CO2 has low viscosity and high diffusivity that make it suitable as a solvent for SFE and as a mobile phase for SFC. Previous chemical investigation of Stillingia lineata ((Lam.) Müll. Arg. Euphorbiaceae) leaves led to the isolation of the rare C20-flexibilane tonantzitlolones (TZLs) (PKC activators and potent anti-tumor agents) [3] and tigliane derivatives (strong inhibitors of Chikungunya viral replication) [4 – 6]. This plant was selected to validate our green approach aiming to specifically extract, then isolate diterpenoids of interest. According to a pre-determined experimental plan, sequential SFE-CO2 was carried out by varying pressure, temperature, flow rate and step duration. For each experiment, an ethanol step gradient was performed, affording six fractions (Figure below). Identification of compounds was achieved by LC-UV-HRMS [2], then compared with standards and classified into different chemical classes (TZLs, diterpenes, chlorophylls and glycosylated flavonoids). Their relative proportions were subsequently determined by measurement of UV peak areas, allowing selecting optimal SFE conditions, and diterpene-enriched fraction for further SFC purifications. This approach not only has the benefit of using eco-friendly methodologies, but it also allows a concurrent prefractionation during the extraction step.

Supercritical fluid extraction of rare earth elements, thorium and uranium from monazite concentrate and phosphogypsum using carbon dioxide containing tributyl phosphate and di-(2-ethylhexyl)phosphoric acid

Supercritical fluid extraction (SCFE) using carbon dioxide containing tributyl phosphate (TBP), di-(2-ethylhexyl)phosphoric acid (D2EHPA) and their adducts with HNO3 is applied for extraction of rare earth elements (REE), thorium (Th) and uranium (U) from monazite concentrate (MC) and phosphogypsum (PG). REE extraction from MC and their separation from Th and U are carried out from the product of MC–Na2CO3 baking (MCS), which is obtained under microwave irradiation, after which the phosphates of REE, Th and U present in the MC are converted into their oxides. Up to 50% of REE can be recovered as the adducts of TBP and D2EHPA with HNO3 from the resulting powdered MCS under SCFE conditions, whereas Th and U remain in the solid phase. After a complete dissolution of the MCS residue in the mixture of 4 M HCl and 0.05 M HF, Th and U are quantitatively extracted using supercritical carbon dioxide (SC CO2) containing D2EHPA and thus separated from the REE that remain in an acidic solution. The conditions of quantitative isolation of REE, Th and U from PG are determined. The schemes for complex processing of MC and PG aimed at REE recovery and their separation from Th and U are suggested.

Application of response surface methodology for the optimization of supercritical fluid extraction of essential oil from pomegranate (Punica granatum L.) peel.

Essential oils and volatile components of pomegranate (Punica granatum L.) peel of the Malas variety from Meybod, Iran, were extracted using supercritical fluid extraction (SFE) and hydro-distillation methods. The experimental parameters of SFE that is pressure, temperature, extraction time, and modifier (methanol) volume were optimized using a central composite design after a (24-1) fractional factorial design. Detailed chemical composition of the essential oils and volatile components obtained by hydro-distillation and optimum condition of the supercritical CO2 extraction were analyzed by GC-MS, and seventy-three and forty-six compounds were identified according to their retention indices and mass spectra, respectively. The optimum SFE conditions were 350 atm pressure, 55°C temperature, 30min extraction time, and 150 µL methanol. Results showed that oleic acid, palmitic acid and (-)-Borneol were major compounds in both extracts. The optimum extraction yield was 1.18 % (w/w) for SFE and 0.21 % (v/w) for hydro-distillation.

Characterization of Arachis hypogaea L. oil obtained from different extraction techniques and in vitro antioxidant potential of supercritical fluid extraction extract

Aim: The present investigation was aimed to characterize the fixed oil of Arachis hypogaea L. using five different extraction methods: Supercritical fluid extraction (SFE), ultrasound assistance extraction, soxhlet extraction, solvent extraction, and three phase partitioning method. Materials and Methods: The SFE conditions (temperature, pressure, and volume of CO 2) were optimized prior for better yield. The extracted oils were analyzed and compared for their physiochemical parameters, high-performance thin layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and Fourier transform infrared spectrometry (FT-IR) fingerprinting. Anti-oxidant activity was also determined using DPPH and superoxide scavenging method. Results: The main fatty acids were oleic, linoleic, palmitic, and stearic acids as obtained by GC-MS. HPTLC analysis revealed the presence of similar major components in chromatograms. Similarly, the pattern of peaks as obtained in FT-IR and GC-MS spectra of same oils by different extraction methods was superimposable. Conclusion: Analysis reported that the fixed oil of A. hypogaea L. is a good source of unsaturated fatty acid, mainly n-6 and n-9 fatty acid with a significant antioxidant activity of oil obtained from SFE extraction method.

Supercritical CO2 extraction of cupuassu butter from defatted seed residue: Experimental data, mathematical modeling and cost of manufacturing

The aim of this work was to perform a techno-economic feasibility study of the supercritical CO2 (scCO2) extraction for obtaining solvent-free cupuassu butter from cold-pressing by-product of cupuassu seeds and assess the influence of thermodynamic and kinetic variables on the yield, chemical composition, and manufacturing cost of the extracts. Phenolic content (0.47–2.82mg/g) was much lower than those found in the literature (20–23mg/g). The high contents of alpha (7.72–18.05mg/g), gamma (233–365mg/g), and delta (11.84–44.10mg/g) tocopherols, as well as the high levels of unsaturated fatty acids (48%) compared to the saturated fatty acids (52%), give the cupuassu butter obtained by supercritical fluid extraction (SFE) a solvent-free product with high value-added and great potential for use as an ingredient in food, pharmaceutical and cosmetic industries. Optimal conditions for SFE of butter regarding extraction kinetics, chemical composition and production costs were 30–35MPa and 50°C.

Antioxidant Properties of Essential Oil Extracted from Pinus morrisonicola Hay Needles by Supercritical Fluid and Identification of Possible Active Compounds by GC/MS.

Pine (Pinus morrisonicola Hay, PM) needles have been used as folk medicine for their antihypertension and lipid-lowering effects. As supercritical fluid extraction (SFE) is considered an ideal technique for the extraction of essential oil from plant materials, the present work investigated the optimal SFE conditions and the protective effects of different resulting fractions of PM needles on lipid peroxidation and foam cell production in macrophages. Nine PM needle extracts (PME1–9) were obtained in 1%–4% yields using different SFE conditions, of which PME1 had the lowest yield (1.1%) and PME3 the highest (3.9%). PME3 exhibited lower cytotoxic effects and stronger inhibition of lipid peroxidation and formation of foam cell in RAW 264.7 macrophages than those of other PME extracts. PME3-1 purified from PME3 by column and thin layer chromatography inhibited LDL oxidation more effectively than did PME3 in a cell-free system oxidized by Cu2+. PME3-1 dose-dependently (25–100 μg/mL) decreased conjugated diene levels and foam cell formation induced by ox-LDL. GC/MS analyses revealed that 1-docosene, neophytadiene, and methyl abietate were increased 5.2-, 1.7- and 4.3-fold in PME3-1 relative to PME3. A new hydrocarbon compound, cedrane-8,13-diol, was identified in PME3-1. Overall, the present study demonstrates the optimal extraction conditions of SFE of PM and identifies the most potent antioxidant fractions and possible active compounds in PM.