Supercritical Fluid Extraction Conditions Research Articles

High Pressure Extraction as a Green Alternative to the Conventional Sunflower Oil (Helianthus annuus) Production Process – Extraction with Pressurized Ethanol in an Intermittent Process and with Supercritical Fluid

AbstractThis research explores green‐technology alternatives to extract vegetable oils as alternatives to hexane, a non‐renewable solvent, focussing on sunflower oil. It compares pressurized liquid extraction (PLE) with ethanol and supercritical fluid extraction (SFE) with CO2. Both processes aim to maximize oil yield, tocopherol content (α, β, γ, and δ), fatty acid profile (FA), and triacylglycerol (TAG) composition. Results show that SFE at 32 MPa achieves an 87.58% oil recovery, while PLE at 84 °C achieves 93.93%. PLE with ethanol extracts polar minority compounds along with the oil due to its higher temperature, favoring extraction. The total tocopherol content is 91.17 mg/100 g of oil in optimized SFE conditions, with α‐tocopherol extraction influenced by temperature, γ and δ‐tocopherol by pressure. PLE yields 83.16 mg/100 g of oil in tocopherols influenced less by process variables. The fatty acid (FA) profile do not vary in the oils obtained from different processes or based on the variables within each process, with linoleic and oleic acids being the most abundant. Similarly, triacylglycerols (TAGs) C54:5 and C54:6 are predominant. The optimization of SFE and PLE processes indicates a strong potential for using green solvents in the extraction of tocopherol‐rich sunflower oil.

Optimizing the Supercritical Carbon Dioxide Extraction of Hibiscus Flower Essential Oil using Response Surface Analysis

The development of Supercritical Fluid Extraction (SFE) has opened the door to the harvesting of plants for a wide range of chemical compounds. This study distilled essential oil from hibiscus flowers utilizing the supercritical CO2 method. Different extraction parameters, including pressure (100-300 bar) and temperature (300-350 K), were studied to visualize how they affected oil recovery. Response surface analysis was used to fine-tune the extraction process. The chemical composition of the recovered oil was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). According to the findings, 13.11% per 80 g of dry flowers is the ideal oil extracted from Hibiscus flowers, using SFE at 200 bar pressure and 325 K extraction temperature. Six compounds were provisionally identified in the extracted oil from hibiscus flowers under optimum SFE conditions.

Comparative analysis of flavonoids extracted from Dendrobium chrysotoxum flowers by supercritical fluid extraction and ultrasonic cold extraction

Flowers are by-products of the medicinal plant Dendrobium chrysotoxum, with high yield but low utilization rate. Extracting flavonoids from D. chrysotoxum flowers can not only reduce resource waste but also bring economic benefits. In this study, two green extraction methods, SFE (supercritical fluid extraction) and UCE (ultrasonic cold extraction) were used to extract flavonoids from D. chrysotoxum flowers, and the response surface method (RSM) was used to optimize the extraction conditions. The results showed that on the optimal conditions of SFE (time 90 min, temperature 50 °C, pressure 20 MPa) and UCE (time 30 min, power 400 W, temperature 40 °C, solid-liquid ratio 1:40 (w:v), ethanol concentration 60%), the total flavonoid extraction yield was 2.04% ± 0.02% and 0.64% ± 0.02%, respectively. In vitro, antioxidant activity analysis showed that both extracts had good antioxidant activity, and the antioxidant activity of SFE extract was higher than that of UCE extract. The quantitative determination of flavonoid compounds showed that the content of quercetin, kaempferol, and catechin in SFE extract was significantly higher than that in UCE extract, and the content of ellagic acid in the two extracts was similar. These results indicated that the two green extraction methods improved the resource utilization of D. chrysotoxum flowers, and SFE was more suitable for extracting flavonoids from D. chrysotoxum flowers than UCE.

Supercritical CO2 Extraction of Seed Oil from Psophocarpus tetragonolobus (L.) DC.: Optimization of Operating Conditions through Response Surface Methodology and Probabilistic Neural Network

For the treatment of menopausal symptoms, nutraceuticals and herbal remedies are thought to be more natural and safer than hormones. Attention has been paid to the winged bean (Psophocarpus tetragonolobus (L.)) DC. seed oil. They are constituted of phytosterols, which may be effective in preventing menopausal symptoms. The purpose was to determine the optimal conditions for supercritical fluid extraction of oleic-rich oil from winged bean seeds. To optimize the condition, the response surface methodology (RSM) and probabilistic neural network (PNN) were utilized. In this research, PNN was used to improve RSM estimation by reducing the number of calculations. The optimized extraction conditions for winged bean seed oil entailed a CO2 flow rate of 21.3 L/h, a pressure of 30 MPa, a temperature of 55 °C, and an extraction time of 90 min. Under these conditions, the extraction process yielded a maximum oil yield of 36.27%. Ultimately, winged bean seed oil included a greater proportion of unsaturated fatty acids such as oleic acid, linoleic acid, and linoleic acid than oil produced using cold pressing or co-solvent extraction.

Antioxidant and Antimicrobial Properties and GC-MS Chemical Compositions of Makwaen Pepper (Zanthoxylum myriacanthum) Extracted Using Supercritical Carbon Dioxide.

This research aimed to optimize pressure (10-20 MPa) and temperature (45-60 °C) conditions for supercritical fluid extraction (SFE) of Makwaen pepper (Zanthoxylum myriacanthum) extract (ME) in comparison to conventional hydro-distillation extraction. Various quality parameters, including yield, total phenolic compounds, antioxidants, and antimicrobial activities of the extracts, were assessed and optimized using a central composite design. The optimal SFE conditions were found to be 20 MPa at 60 °C, which resulted in the highest yield (19%) and a total phenolic compound content of 31.54 mg GAE/mL extract. IC50 values for DPPH and ABTS assays were determined to be 26.06 and 19.90 μg/mL extract, respectively. Overall, the ME obtained through SFE exhibited significantly better physicochemical and antioxidant properties compared to ME obtained through hydro-distillation extraction. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that beta-pinene was the major component in the ME obtained through SFE (23.10%), followed by d-limonene, alpha-pinene, and terpinen-4-ol at concentrations of 16.08, 7.47, and 6.34%, respectively. On the other hand, the hydro-distillation-extracted ME showed stronger antimicrobial properties than the SFE-extracted ME. These findings suggest that both SFE and hydro-distillation have the potential for extracting Makwaen pepper, depending on the intended purpose of use.

DEVELOPMENT OF THE COMPOSITION OF THE MEDICAL AND PREVENTIVE TOOTHPASTE WITH EXTRACT OF SAGE, JUNIPER AND CHAMOMILE

Currently, the trend in the cosmetics industry is to produce natural, ecological products with the preservation of the most complete set of components of the raw materials. The work is devoted to the development of the composition of therapeutic and preventive toothpaste with СО2 extracts of sage, chamomile and juniper. The extracts included in the toothpaste formulation were obtained using supercritical carbon dioxide extraction. In order to choose the optimal conditions for the extraction, we found out the influence of the technological modes of the process on the composition of the extracts. For this purpose, at the first stage, a series of studies on the dependence of the quantitative yield of extracts on pressure was carried out. On the basis of experimental data, the optimal conditions for supercritical fluid extraction were determined. At the second stage of the research, the influence of temperature on the composition of supercritical fluid extracts of sage was studied, which made it possible to determine the temperature parameter of the process. The optimal ratio of extracts in the composition of therapeutic-prophylactic toothpaste has been established. The next stage of research was the selection of the base of the toothpaste, namely an abrasive component that combines a high cleaning capacity with a low abrasion capacity and a thickener (Blanose 7M3 IF). To determine the composition of the toothpaste base, the rheological characteristics of seven formulations of the base, which was obtained from an abrasive component, a thickener, and glycerin, were determined. The toothpaste system is an emulsion-suspension, which during storage can excessively thicken or delaminate, therefore, in order to predict the stability of the rheological properties of the paste, we conducted experiments on the storage of the toothpaste base at a temperature of 25°C for 1.5 months. The work shows that the base of the toothpaste acquires indicators of constant viscosity on the 13-14th day from the moment of release. As a result of the work carried out, a formulation of toothpaste for therapeutic and preventive purposes was developed. In order to confirm the quality of the finished cosmetic product, we examined it according to physic-chemical indicators, namely, appearance, color, smell, taste and hydrogen index (pH).

Influence of different extraction methods on the compound profiles and functional properties of extracts from solid by-products of the wine industry

This study evaluated the impact of three different extraction methods, agitation, ultrasound, and supercritical fluid extraction (SFE), on the functional properties and bioactive compound profiles of stalks, a by-product of the wine industry. For agitation and ultrasound methods different concentrations of ethanol as solvent were evaluated while for optimization of SFE conditions Response Surface Methodology (RSM) was applied. Supercritical fluid conditions with 270 and 300 bar, 50 and 40 °C and 3 and 2 extraction hours were optimal to obtain high extraction yields and extracts with high antioxidant activity, respectively. The extracts obtained by SPE at high pressures and temperatures (300 bar and 50 °C) showed antihypertensive activity and higher activity against bacteria while those obtained at low pressures and medium temperatures (200 bar and 45 °C) presented higher activity against yeasts. Extracts obtained with the agitation and ultrasound methods were rich in phenolic compounds and showed higher antioxidant activity, while those extracted with supercritical fluids contained higher amounts of lipophilic substances such as terpenoids, fatty acids and oxylipins associated to antihypertensive and antimicrobial activities. The effective recovery of their entire host of bioactive components will increase the overall value of the industry by decreasing the production of agricultural residues.

Supercritical CO2 Extraction of High-Added Value Compounds from Chlorella vulgaris: Experimental Design, Modelling and Optimization.

Microalgae are well-known for their high-added value compounds and their recovery is currently of great interest. The aim of this work is the recovery of such components from Chlorella vulgaris through supercritical fluid extraction (SFE) with CO2. The effect of the extraction temperature (40–60 °C), pressure (110–250 bar), and solvent flow rate (20–40 g/min) was tested on yield, the extract’s antioxidant activity, and the phenolic, chlorophyll and carotenoid content. Thus, data analysis indicated that the yield was mainly affected by temperature, carotenoids by pressure, while the extract’s phenolics and antioxidant activity were affected by the synergy of temperature and pressure. Moreover, SFE’s kinetic study was performed and experimental data were correlated using Sovová’s mass transfer-based model. SFE optimization (60 °C, 250 bar, 40 g/min) led to 3.37% w/w yield, 44.35 mgextr/mgDPPH antioxidant activity (IC50), 18.29 mgGA/gextr total phenolic content, 35.55, 21.14 and 10.00 mg/gextr total chlorophyll, carotenoid and selected carotenoid content (astaxanthin, lutein and β-carotene), respectively. A comparison of SFE with conventional aq. ethanol (90% v/v) extraction proved SFE’s superiority regarding extraction duration, carotenoids, antioxidant activity and organoleptic characteristics of color and odor despite the lower yield. Finally, cosolvent addition (ethanol 10% w/w) at optimum SFE conditions improved the extract’s antioxidant activity (19.46%) as well as yield (101.81%).

Rapid fingerprint analysis based on supercritical fluid chromatography for quality evaluation of Hedyotis diffusa

In this study, quality evaluations of Hedyotis diffusa (H. diffusa) batches by rapid fingerprint analysis based on supercritical fluid chromatography (SFC) were accomplished. Abundant chemical components of H. diffusa were effectively extracted by optimal supercritical fluid extraction conditions (20 % MeOH as modifier, 45 °C, 300 bar and 60 min). Then, the extract was separated by SFC on a Torus 1-AA column (100 × 3.0 mm i.d., 1.7 µm) within 10 min by gradient elution increasing from 5 % to 45 % modifier (MeOH containing 0.05 % TFA) at 1.2 mL/min, 30 °C and 2000 psi. The SFC approach exhibited short analysis time, while maintaining good peak shape and resolution. Seven major compounds were further identified by SFC coupled with tandem mass spectrometer to be phenylpropanoid, iridoids and anthraquinones. Finally, fingerprint analysis of 10 batches of H. diffusa by the developed SFC method was accomplished. The similarity values were between 0.894 and 0.968, indicating quality differences of H. diffusa from depending on origin and harvest year exist. The result demonstrates the feasibility of the SFC in batch quality evaluation of H. diffusa.

A comparative study of supercritical fluid extraction and accelerated solvent extraction of lipophilic compounds from lignocellulosic biomass

The Box-Behnken experimental design technique investigated a comparative study of supercritical fluid extraction (SFE) and accelerated solvent extraction (ASE) of lipophilic compounds from pinewood sawdust. A response surface methodology was used to examine the effect of independent parameters and optimize the extraction yield of lipophilic compounds. The results showed that the increase in extraction temperature used for ASE positively influenced the yield of lipophilic compounds, whereas an increase in the flow rate of the cosolvent at temperature 50 °C, and pressure of 300 bar increased the yield achieved by SFE. The experimental data's quadratic polynomial models gave a coefficient of determination (R2) of 0.87 and 0.80 for ASE and SFE, respectively. The optimum conditions of ASE were temperature (160 °C), static time (12.5 mins), and static cycle (1), which resulted in a maximum yield of 4.2%. The optimum SFE conditions were temperature (50 °C), pressure (300 bar), carbon dioxide (CO2) flow rate (3.2 ml/min), and a 2 ml/min cosolvent flow rate that yielded 2.5% lipophilic compounds. ASE yielded higher extraction efficiency than SFE. Fourier transform infra-red (FTIR) spectroscopy and thermal analyses TGA/DSC evaluated the ultimate analyses of the lipophilic extracts. The FTIR results confirmed the presence of aliphatic groups, hydroxyl groups, and carboxyl groups. The thermal analysis showed that the degradation temperature of the lipophilic compounds occurred between 250 and 450 °C. Thereafter, Pyrolysis-Gas Chromatography Mass Spectrometry (Py-GC/MS) was used to identify the lipophilic compounds, which showed that the extracts were rich in fatty acids and terpenes.

Optimization of Extraction of Phenolic Compounds with Antimicrobial Properties from Origanum vulgare

Oregano (Origanum vulgare) is considered to be a good and cheap source of phenolic compounds with favorable biological activities, especially antimicrobial and antioxidant properties. Hypothesis/Purpose: The current work explored the optimization of the process conditions of solid–liquid extraction from Origanum vulgare to obtain extracts with high antimicrobial activity. We investigated which parameters promoted different efficiencies, leading to the maximum extraction of phenols and the consequent highest level of biological activity. Design-Expert Pro 11 was selected to design and analyze the experiments. The extracts were obtained by maceration as a simple method to recover value-added compounds from plant material, and supercritical fluid extraction was carried out as a green method with a high selectivity to obtain the compounds of interest. Pressure, temperature, and time were varied to obtain extracts with high antioxidant and antimicrobial activity. According to the results obtained using Design-Expert, the optimal conditions for maceration were at a temperature of 83 °C. The 1,1′-diphenyl-2-picrylhydrase method was used for the determination of antioxidant potential, while microdilution methods were used to determine the antimicrobial potential with regard to Staphylococcus aureus, Escherichia coli, and Candida albicans. A level of antioxidant activity of 87.21% was achieved. Supercritical fluid extracts showed higher antioxidant activity at a higher temperature of 60 °C and higher pressure of 25 MPa, although the results at 40 °C and 25 MPa were similar. The lowest minimum inhibitory concentration (MIC) values were 0.147 mg/mL for S. aureus, 0.728 mg/mL for E. coli, and 0.311 mg/mL for C. albicans. Overall, the optimal conditions for supercritical fluid extraction were 25 MPa and 40 °C. On the other hand, amounts of 0.208 mg/mL for S. aureus, 1.031 mg/mL for E. coli and 0.872 mg/mL for C. albicans were obtained using maceration. The MIC values of extracts obtained by supercritical fluid extraction were comparable to the minimum inhibitory concentration values obtained by different conventional techniques, such as those of Clevenger and Soxhlet.

Comparative Studies of Selected Criteria Enabling Optimization of the Extraction of Polar Biologically Active Compounds from Alfalfa with Supercritical Carbon Dioxide

The aim of this research was to provide crucial and useful data about the selection of the optimization criteria of supercritical carbon dioxide extraction of alfalfa at a quarter-technical plant. The correlation between more general output, including total phenolics and flavonoids content, and a more specified composition of polar constituents was extensively studied. In all alfalfa extracts, polar bioactive constituents were analyzed by both spectrometric (general output) and chromatographic (detailed output) analyses. Eight specific phenolic acids and nine flavonoids were determined. The most dominant were salicylic acid (221.41 µg g−1), ferulic acid (119.73 µg g−1), quercetin (2.23 µg g−1), and apigenin (2.60 µg g−1). For all seventeen analyzed compounds, response surface methodology and analysis of variance were used to provide the optimal conditions of supercritical fluid extraction for each individual constituent. The obtained data have shown that eight of those compounds have a similar range of optimal process parameters, being significantly analogous for optimization based on total flavonoid content.

Effect of drying methods on biorefinery process to obtain capsanthin and phenolic compounds from Capsicum annuum L.

Red peppers (Capsicum annuum L.) that are eliminated as waste due to its low quality for commercialization were used as raw material to recover bioactive compounds in a biorefinery approach. The effect of temperature (40, 60 °C) and pressure (15, 25, 35 MPa) was evaluated on the oleoresin extraction yield and carotenoids composition obtained by supercritical fluid extraction (SFE). The effect of drying technique (solar drying, conventional oven, and freeze-drying) was evaluated. Sequentially, the effect of solvent type (100% ethanol and 75% (vol/vol) ethanol) using pressurized liquid extraction (PLE) was evaluated on the recovery of phenolic compounds and antioxidant activity. The best SFE condition was 60 °C and 25 MPa. The drying methods did not significantly affect carotenoids recovery by SFE. For PLE, the composition of the solvent influenced the extraction yield and composition. The highest values for total phenolic compounds and antioxidant activity were obtained using 100% ethanol as solvent.

Functional properties of extracts and residual dietary fibre from pomegranate (Punica granatum L.) peel obtained with different supercritical fluid conditions

The objective of this study was the optimization of supercritical fluid extraction (SFE) using CO2 for extraction of bioactive compounds from pomegranate peel, evaluating the functional properties of different extracts (SFE extracts and alcohol-insoluble residues (AIR)). A Box–Behnken design combined with response surface methodology (RSM) was used to optimize extraction pressure (250–300 bar), temperature (45–55 °C) and time (2–4 h). The results showed that these SFE conditions have a significant effect on the responses studied. Antioxidant activities of the extracts, residual dietary fibre and pectin were the parameters that best fitted the quadratic model developed in this study. RSM optimization of these parameters was performed using Derringer's desired function methodology, estimating optimal conditions for extraction pressure (291 bar), temperature (46.5 °C) and time (2.5 h). The results reveal that supercritical technology is an interesting option for fractionating and recovering high-value compounds from pomegranate by-products.

Response Surface Methodology for Optimization of Supercritical Fluid Extraction of Orange Peel Essential Oil

Background: Orange peel essential oils were obtained using supercritical fluid extraction. This method is an important high scaling extraction method used for the extraction of plant and animal extracts.
 Objectives: The aim of this study was the optimization of the extraction of the orange peel essential oil.
 Methods: The experimental parameters of Supercritical Fluid Extraction (SFE) such as temperature, pressure, and extraction time, and modifier volume were optimized using a central composite design after a 24-1 fractional factorial design. Orange peels were collected from ripe orange and were washed, air dried, and milled. Then, a Suprex MPS/225 system in the SFE mode with a maximal operating pressure of 395 bars was used for essential oil extraction. Moreover, GC-MS and GC-FID were used for the identification and determination of oil compounds, respectively.
 Results: Eight compounds have been identified based on their retention indices and mass spectra. According to the results, α-pinene, β-pinene, myrcene, d-limonene, terpinolene, C8-aldehyde, citronellol, and linalool were identified in orange peel essential oil. The optimum SFE conditions were obtained at a pressure of 347.07 atm, temperature of 55° C, extraction time of 30.16 min, and ethanol volume of 147.05 µL. Moreover, extraction yields based on SFE varied in the range of 0.04% to 1.18% (w/w). 
 Conclusion: The Results showed supercritical fluid technology as the best alternative technique for the extraction of pure and high-quality essential oil from orange peel. It is a green method and does not have any environmental impact.

Supercritical Fluid Extraction Combined with Ultrahigh Performance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry for Determination of Extractables to Evaluate Compatibility of Drugs with Rubber Closures.

Biological activity and pharmacological efficacy of protein drugs may be affected by the compatibility between drug and packaging materials. The compatibility of rubber closures seal cap has become the focus of many studies due to its complicated formulation. Despite of the significance of the issue, currently, there is little available data about organic leachables in drugs which is also not comprehensive. Since the concentration of migrants in drug is usually low and the matrix is complicated, the establishment of overall profile of extractables is crucial for the characterization of leachables. Herein, the supercritical fluid extraction (SFE) method was used because of its great extraction capacity and efficiency for low to medium polar extractables in rubber stoppers. The SFE conditions were optimized by response surface methodology (RSM). Experimental results of the extract yield were close to the predicted values (R2 = 0.95). Then the extractables were qualitatively and quantitatively analyzed with ultrahigh performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS). Finally, risk assessment was made by comparing predicted exposure with injection permitted daily exposure (pPDE) limit or threshold recommended by threshold of toxicological concern (TTC). The results showed that there are many extractables such as glyceride, fatty acids and derivatives, antioxidants, and degradation products. Among them degradation products were in the majority and content of 17 substances exceeded corresponding limits. Considering their unknown toxicology, more experiments are therefore needed to provide information on their toxicology and risk assessment. The study provides a reference for the compatibility of drugs, and quality supervision of pharmaceuticals packaging.

Optimized Extraction of Phenylpropanoids and Flavonoids from Lemon Verbena Leaves by Supercritical Fluid System Using Response Surface Methodology.

The aim of this work was to optimize the recovery of phenolic compounds from Lippia citriodora using supercritical fluid extraction (SFE). To achieve this goal, response surface methodology based on a 23 central composite design was used to evaluate the effects of the following experimental factors: temperature, pressure and co-solvent percentage. The effects of these variables on the extraction yield and total polar compound contents were evaluated. With respect to the phytochemical composition, an exhaustive individual phenolic compound quantitation was carried out by HPLC-ESI-TOF-MS to analyze the functional ingredients produced by this system design. To the best of our knowledge, this is the first time that a standardized supercritical fluid process has been developed to obtain functional ingredients based on phenolic compounds from L. citriodora in which the individual compound concentration was monitored over the different SFE conditions. The results enabled the establishment of the optimal technical parameters for developing functional ingredients and revealed the main factors that should be included in the extraction process control. This functional food ingredient design could be used as a control system to be applied in nutraceutical and functional food production industry.

Artocarpus altilis extracts as a food-borne pathogen and oxidation inhibitors: RSM, COSMO RS, and molecular docking approaches

Lipid oxidation and microbial contamination are the major factors contributing to food deterioration. Food additives like antioxidants and antibacterials can prevent food spoilage by delaying oxidation and preventing the growth of bacteria. Artocarpus altilis leaves exhibited biological properties that suggested its use as a new source of natural antioxidant and antimicrobial. Supercritical fluid extraction (SFE) was used to optimize the extraction of bioactive compounds from the leaves using response surface methodology (yield and antioxidant activity). The optimum SFE conditions were 50.5 °C temperature, 3784 psi pressure and 52 min extraction time. Verification test results (Tukey’s test) showed that no significant difference between the expected and experimental DPPH activity and yield value (99%) were found. Gas-chromatography –mass spectrometry (GC-MS) analysis revealed three major bioactive compounds existed in A. altilis extract. The extract demonstrated antioxidant and antibacterial properties with 2,3-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, ferric reducing ability of plasma (FRAP), hydroxyl radical scavenging activity, tyrosinase mushrrom inhibition of 41.5%, 8.15 ± 1.31 (µg of ascorbic acid equivalents), 32%, 37% and inhibition zone diameter of 0.766 ± 0.06 cm (B. cereus) and 1.27 ± 0.12 cm (E. coli). Conductor like screening model for real solvents (COSMO RS) was performed to explain the extraction mechanism of the major bioactive compounds during SFE. Molecular electrostatic potential (MEP) shows the probability site of nucleophilic and electrophilic attack during bacterial inhibition. Based on molecular docking study, non-covalent interactions are the main interaction occurring between the major bioactive compounds and bacteria (antibacterial inhibition).

Optimization of supercritical-CO2 extraction of Iris lactea seed oil: Component analysis and antioxidant activity of the oil

Iris lactea Pall. var. chinensis (Fisch.) Koidz. is a widely distributed species and the seeds of this species have been used as medicine. However, the chemical composition and biological activities of the I. lactea seed oil (ILSO) have not been studied. In this present work, extraction time, temperature, and pressure were considered as variables and response surface methodology based on the Box-Behnken design was utilized to identify the optimal conditions for supercritical fluid extraction of the ILSO. Furthermore, the main components (including fatty acids, unsaponifiables, and volatile components) in ILSO extracted with the above optimal conditions were identified by gas chromatography-mass spectrometry. It was found that major fatty acids present in ILSO were linoleic acid (41.31 %), oleic acid (34.74 %), and docosahexaenoic acid (3.18 %). The total content of sterols reached as high as the level of 87.44 % in unsaponifiable matter and sterols with a content over 5% included β-sitosterol (27.14 %) stigmasterol (18.38 %), delta5-avenasterol (15.36 %), campesterol (13.21 %), and betulinicaldehyde (5.80 %). The physicochemical properties of ILSO were analyzed according to Chinese national standards. Total polyphenol content (TPC) and total tocopherol content of ILSO were also determined. These predominant compounds were known by their high biological activities and confirm the potential sources of bioactive compounds existing in ILSO. Based on these identified ingredients, the antioxidant activity of the ILSO was evaluated by two different methods. The antioxidant capacity of ILSO determined by FRAP method was equivalent to 0.4759 m mol/L FeSO4·7H2O and 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity in vitro with IC50 value of 3.27 mg/mL. These results provide a rich chemical database for the development of a new oil resource, as well as the possibility of using a byproduct in the production of pharmaceuticals and a rich resource of ornamental plants.

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.