Extraction of Poppy Seed Oil Using Supercritical CO2

ABSTRACT: Extraction of poppy seed oil with supercritical carbon dioxide (SC-CO₂) was performed and the effect of extraction conditions on oil solubility and yield as well as oil composition was evaluated. Within the temperature (50 to 70 °C) and pressure (21 to 55 MPa) ranges studied, 55 MPa/70 °C gave the highest oil solubility (24.1 mg oil/g CO₂) and oil yield (38.7 g oil/100g seed). Fatty acid composition of the oil obtained with SC-CO₂ at 55 MPa/70 °C was similar to that of petroleum ether-extracted oil ( p > 0.05) with linoleic acid making up 69.0 to 73.7% of fatty acids. Tocol content of the SC-CO₂-extracted oils varied from 22.37 to 33.35 mg/100 g oil, which was higher than that of petroleum ether-extracted oil (15.28 mg/100 g oil). Poppy seed oil may have potential in the rapidly growing specialty oil market.     

Inactivation Efficiency of Enzymes in Buffered System by Continuous Method with Microbubbles of Supercritical Carbon Dioxide

ABSTRACT: Continuous method with microbubbles of supercritical carbon dioxide (SC-CO₂) was applied to enzyme inactivation in a buffer system, which has a buffer capacity similar to commercial liquid foods (natural juices, fruit drinks, Japanese sake). By continuous treatment with microbubbles of SC-CO₂, α-amylase and acid protease were effectively inactivated rather than by heat treatments. Compared with the inactivation efficiencies of these enzymes in deionized water by continuous treatment with microbubbles of SC-CO₂, that of α-amylase was slightly lower, but that of acid protease was not in the buffer system. These results suggest that this method enables the effective inactivation of enzymes, although inactivation efficiency by this method was affected by initial pH and the buffer action of samples.     

SUPERCRITICAL CARBON DIOXIDE TREATMENT TO INACTIVATE AEROBIC MICROORGANISMS ON ALFALFA SEEDS

The supercritical carbon dioxide (SC-CO₂) process involves pressurizing CO₂ in a chamber which generates liquid phase of carbon dioxide. Pressurized liquid CO₂ has a strong extraction capability of organic and inorganic compounds. The recent studies have also demonstrated that antimicrobial effect of SC-CO₂ due extraction some cellular components of microorganisms. The efficacy of a supercritical carbon dioxide treatment on alfalfa seeds contaminated with Escherichia coli K12 was tested at 2000, 3000, and 4000 psi at 50C. Samples were treated for 15, 30, and 60 min at each pressure. After pummeling the seed samples in 0.1% peptone water, the initial and final Escherichia coli and total aerobic bacteria on the seeds were determined by plating on 3M Petri Films. After 48 h of incubation at 37 C, the colonies were enumerated. Treated seeds were evaluated in terms of germination characteristics. For aerobic plate count, the effect of pressure in the range of 2000–4000 psi was not statistically significant (p > 0.05) even though 85.6% inactivation was achieved at 4000 psi for 60 min. For E. coli, the reductions for 2000, 3000, and 4000 psi treatments for 15 min were 26.6, 68.1, and 81.3%, respectively. As the time was increased from 15 to 60 min at 4000 psi, the percent E. coli reduction increased from 81.3% to 92.8%. The percent germination for all treatments was over 90%. There was no significant difference (p > 0.05) in the germination rate of treated and untreated seeds. Supercritical carbon dioxide treatments demonstrated a reduction of E. coli K12 and total aerobic counts without affecting the germination characteristics of alfalfa seeds (p < 0.05). This study was a step in the direction of improving safety of alfalfa seeds used to produce fresh sprouts, which have been the cause of several outbreaks.     

MODELING OF SELECTIVE EXTRACTION OF PHOSPHATIDYLCHOLINE FROM A COMPLEX LECITHIN MIXTURE USING SUPERCRITICAL CO2/ETHANOL

Phospholipids are not soluble in pure carbon dioxide used in supercritical flucid extraction due to their nonpolar nature. However, addition of ethanol as an entrainer makes it possible to selectively extract phoshatidylcholine (PC) from a phospholipid mixture. Phosphatidylcholine has a potential value in the pharmaceutical industry. In this study, two different models to predict the extraction behavior of phospholipids (a multicomponent system) with an entrained supercritical fluid (carbon dioxide/ethanol) were evaluated. The models developed for selective extraction of PC from a complex lecithin mixture were a mixed-flow model with an overall mass transfer coefficient as well as a shrinking-core model. Both models gave similar results in predicting the experimental data due to two main reasons: (1) shrinking-core model was developed with the perfect mixing assumption of the fluid phase, and (2) extraction of phospholipids from the lecithin mixture with SC-CO₂/ethanol was a slow process.     

MODELING of TRIGLYCERIDE DISTRIBUTION and YIELD of ANHYDROUS MILK FAT IN A CONTINUOUS SUPERCRITICAL CARBON DIOXIDE EXTRACTION SYSTEM

A mathematical model was developed for continuous extraction of multicomponent mixture anhydrous milk fat (AMF) with supercritical carbon dioxide (SC-CO₂) as its solvent. At a constant temperature and pressure, the triglyceride mixture was separated into vapor and liquid fractions. the composition distribution (indicated by acyl carbon number), mass distribution and yield of AMF were calculated by the model based on thermodynamic equilibrium and material balance. the feed composition and distribution coefficient were required information in this model. the experimental values for the extract were in good agreement with the model used. the results for the raffinate were not as precisely modeled. the main factors which affected the model were temperature, pressure, solvent/feed ratio and extract fraction.     

Extraction of ginger rhizome: kinetic studies with supercritical carbon dioxide

The rates of extraction of [6]-gingerol from ground dried Jamaican ginger rhizomes were determined in supercritical carbon dioxide over the pressure range 128–197 bar (1850–2850 psi) and the temperature range 50–65°C. The CO₂ densities varied from 0.415 to 0.775 g cm⁻³. First-order plots showed two approximately linear sections with an initial intercept. The first linear section corresponded to a relatively fast initial extraction stage while the last 20% or so of the gingerol was extracted in the much slower subsequent stage. Reducing the ginger particle size by a factor of 3 increased the rate constant of the fast stage nine-fold. Despite the low viscosity of the supercritical fluid, the rate constants of the fast stage were much smaller than in extractions with organic solvents. Only when the CO₂ density was increased to 0.775 g cm⁻³ did the rate constant of the fast stage rise to a value comparable with, but still smaller than, those in organic solvents of similar density. The rate constants of the later slow extraction stage were also somewhat smaller than the corresponding values in organic solvents at 30°C.     

Optimization of the Supercritical Fluid Extraction of Natural Vitamin E from Wheat Germ Using Response Surface Methodology

ABSTRACT: Natural vitamin E was extracted by supercritical fluid extraction of carbon dioxide (SFE-CO₂) from wheat germ. Several SFE-CO₂ parameters, such as extracting pressure, extracting temperature, and flow rate of carbon dioxide were examined as the independent variables of central composite rotate design (CCRD). Through the response surface methodology (RSM), the optimal processing conditions were determined and the quadratic response surfaces were drawn from the mathematical models. The results demonstrated that the extracting pressure, temperature, pressure × temperature interaction, and flow rate of CO₂ significantly affected the yield of the natural Vitamin E's extraction, while two interactions containing the flow rate of CO₂ had no significant effect on the yield of natural vitamin E. The optimal processing conditions of the extraction of natural vitamin E in wheat germ by SFE-CO₂ were: extracting pressure 5000 PSI, extracting temperature 316 K, and flow rate of carbon dioxide 1.7 ml/min. Optimum value predicted by RSM for the concentration of natural vitamin E was 2307 mg/100g. Close agreement between experimental and predicted values was obtained.     

Reducing the coumarin content of tonka bean extracts using supercritical CO2

By supercritical fluid CO₂ extraction of tonka beans a lipophilic top phase and a crystalline base phase were obtained. These were analysed by gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC) and compared with an ethanolic extract of the same batch of tonka beans. It was shown that the three samples differed considerably in their composition and that the bulk of the main compound coumarin was present in the base phase of the CO₂ extraction.     

Supercritical CO2 extraction of grappa volatile compounds

A first study on the recovery of aromatic extracts from grappa by means of supercritical fluid extraction (SFE) on a laboratory plant has been performed, to obtain aroma extracts at low ethanol content. The influence of extraction parameters like pressure, temperature and flow rate have been studied. Extraction yields have been evaluated for ethanol, higher alcohols and esters of short and medium chain acids. A higher aroma volatile compounds extraction has been obtained when the strongest extraction condition has been considered (200 bar, 60 °C, 0.3 kg h⁻¹). Sensory evaluation has indicated as preferred the extract obtained under mild condition (80 bar, 40 °C, 0.3 kg h⁻¹).     

醇提超临界蜂胶剩余物的性质及其微胶囊粉末的制备

对超临界蜂胶的利用价值及其应用进行探讨。采用HPLC 法、国家标准法对蜂胶黄酮种类、总黄酮含量和抗氧化能力进行测定,采用冷冻干燥法对剩余物进行包埋。结果表明：醇提超临界萃取蜂胶剩余物的总黄酮含量为118.798mg/kg,与醇提蜂胶接近;不同蜂胶品对油脂的过氧化保护作用的强弱顺序是醇提蜂胶＞醇提超临界萃取蜂胶剩余物＞超临界蜂胶,说明超临界蜂胶剩余物也有一定的抗氧化作用;包埋后制备出的微胶囊产品粉质细腻、质地疏松,包埋率可达到69.87%。     

Screening for Phase II Enzyme-inducing and Antioxidant Activities of Common Vegetables

ABSTRACT: Quinone reductase (QR)-inducing activity of aqueous and ethanolic extracts of common vegetables was determined using a murine hepatoma (Hepa 1c1c7) cell bioassay. QR induction observed for aqueous extracts reached 13-fold for corn, 8-fold for kale, and 5-fold for snap beans. QR induction of ethanol extracts reached about 3-fold for both garlic and snap beans, and about 2-fold for both red beetroots and kale. These aqueous extracts were effective inhibitors (kale ∼ red beetroots > corn ∼ green beans > garlic) of the generation of 2-2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical cation (ABTS^•+) by metmyoglobin and H₂O₂, whereas the ethanolic extracts were not inhibitory. Aqueous extracts reduced pre-formed ABTS^•+ more effectively (> 95% inhibition) than did ethanolic extracts (∼50 to 90% inhibition). All vegetable extracts inhibited oxyradical-mediated β-carotene bleaching, where kale and red beetroot extracts exhibited the strongest protective effect.     

Effects of supercritical carbon dioxide extraction conditions on yields and antioxidant activity of Chlorella pyrenoidosa extracts

Yields and antioxidant activity of Chlorella pyrenoidosa extracts obtained by supercritical carbon dioxide extraction through an orthogonal experiment (L₁₆(4⁵)) were investigated to get the best extraction conditions. The results showed that extraction pressure, temperature and modifier were the main three variables that influenced the yields of extracts. The highest yield was obtained at 32 °C, 40 MPa, 20 L h⁻¹ with dosage of modifier 1 mL ethanol g⁻¹ sample for 3 h. Moreover, increasing pressure and concentrations of modifier led to the increase of extraction yields and antioxidant activity. DPPH radical scavenging method showed that almost all the extracts had significantly higher antiradical activities varying from 29.67 ± 0.29% to 54.16 ± 4.49% comparing to -tocopherol, Trolox, and BHT as references except extracts at 32 °C, 35 MPa and 15 L h⁻¹ without modifier for 1.5 h. These results indicate that supercritical extraction is a promising alternative process for recovering compounds of high antioxidant activity from C. pyrenoidosa.     

Effects of processing conditions on the chemical distribution of mate tea leaves extracts obtained from CO2 extraction at high pressures

This work reports the effects of industrial manufacturing steps on the distribution of chemical components of the extracts obtained from supercritical carbon dioxide (SCCO₂) of processed mate tea leaves. For this purpose, samples of mate tea leaves were collected from the actual industrial processing after the fast pre-heating, drying and storage (5 and 21 days) steps. To provide a consistent basis for comparisons, extractions were also conducted for the unprocessed leaves fed in the industrial environment. In order to select the appropriate extraction parameters at high pressure, it was evaluated the effects of temperature from 15 to 55 °C and pressure from 10 to 20 MPa on the liquid yield of unprocessed mate tea leaves. The SCCO₂ extraction experiments regarding the effects of industrial processing conditions were then performed at 35 °C and 20 MPa and the extract chemical analyses were carried out in a GC/MSD. Results show that the extraction yield and chemical composition of the extracts are strongly affected by the industrial processing steps. Chromatographic analyses permitted the identification of caffeine, theobromine, hexadecanoic acid, phytol, squalene, octacosanol, 2-heptacosanone, steroids and triterpenes as the main constituents in the extracts.     

Deoiling of Crude Lecithin Using Supercritical Carbon Dioxide in the Presence of Co-solvents

ABSTRACT: Deoiling of crude soybean lecithin using supercritical fluid mixtures of carbon dioxide and 2 different co-solvents, ethanol and acetone, was studied at 62 °C and at pressures of 170 and 200 bars. Both ethanol and acetone increased the solubility of oil considerably without any significant coextraction of phospholipids. It was shown that deoiling could be achieved at lower pressures when a co-solvent is used leaving behind a valuable product of high content phospholipids, whereas negligible oil extraction was observed with pure CO₂ at the same conditions.     

Extraction of ginger rhizome: partition constants and other equilibrium properties in organic solvents and in supercritical carbon dioxide

Equations have been derived for the direct and indirect methods of determining partition constants for constituents extracted from food and other natural materials. A careful distinction is drawn between mass and volume partition constants. The direct method has been applied to the extraction of [6]-gingerol from Jamaican ginger rhizome with supercritical carbon dioxide and the indirect method to its extraction with acetone, dichloromethane, ethanol and isopropanol. The resulting average mass partition constants were 0.2₉ and 0.3₉, respectively. The content of [6]-gingerol in the original ginger rhizome was found to be 31–32μmol g⁻¹. The extent of oleoresin extraction from the ground ginger and the degree of swelling and organic solvent uptake were also measured.     

Supercritical carbon dioxide extraction of okra (Hibiscus esculentus L) seeds

Pilot‐scale supercritical fluid extraction of okra seeds was carried out, using carbon dioxide as solvent, at temperatures of 40, 50 and 60 °C and pressures of 150, 300 and 450 bar. Laboratory‐scale Soxhlet extraction of the ground seeds was carried out with ethanol and n‐hexane. The yields of supercritical fluid extraction and n‐hexane Soxhlet extractions were similar. The ethanol Soxhlet extraction gave the highest yield, but the concentrations of β‐sitosterol and tocopherols in this extract were lower than in the supercritical fluid extraction product. The fatty acid profiles of the extracts were determined, and a high unsaturated/saturated ratio was observed. The fatty acid compositions were only slightly different for oils obtained by the different extraction methods. Copyright © 2005 Society of Chemical Industry     

甜瓜蒂中葫芦素的超临界CO2流体提取及HPLC分析

为系统全面的研究SFE-CO₂流体萃取甜瓜蒂中葫芦素的过程,对主要控制变量进行全面分析,通过单因素实验研究携带剂用量、萃取温度、萃取压力、萃取时间、CO₂流速及粒度对葫芦素萃取率的影响,并在单因素实验的基础上,采用正交试验优化SFE-CO₂葫芦素的萃取工艺,得出SFE-CO₂萃取葫芦素最佳条件为:携带剂用量200 mL、萃取温度35℃、萃取压力25 MPa、萃取时间30 min、CO₂流速20 kg·h-1、粒度60~80目,在此条件下葫芦素的萃取率为1.443%。使用HPLC对萃取物进行分析。结果显示甜瓜蒂中含有葫芦素B、D、E和I,含量依次为7.83、1.03、3.25、2.38 mg·g-1,以葫芦素B为主,结果表明SFE-CO₂萃取葫芦素可避免热敏性葫芦素的损失。     

EXTRACTION OF VICTORIA AND RED GLOBE GRAPE SEED OILS USING SUPERCRITICAL CARBON DIOXIDE WITH AND WITHOUT ETHANOL

SFE of the oils of two varieties of grape seeds (Victoria and Red Globe) was performed in a flow apparatus at 40C and 250 bar. The effect of the solvent on the extraction yield was studied using CO₂ and CO₂ modified with ethanol, and the yield of extraction was compared with conventional extraction methods (Bligh and Dyer and Soxhlet using hexane). SC CO₂  +  ethanol extracted higher lipid amounts from both varieties, compared with SC CO₂ extraction. The comparison between SFE and conventional extraction methods showed that the highest extraction yield was obtained with SC CO₂  +  ethanol (10%, w/w) (14.7 and 11.8% for Red Globe and Victoria grape seeds, respectively), while pure SC CO₂ afforded the lowest lipid yields. The fatty acid compositions of the oils obtained by SFE were analyzed. Fractions containing higher proportions of PUFAs were obtained at lower solvent/dry grape seed ratios, while fractions richer in SFAs and MUFAs were obtained at higher solvent/dry grape seed ratios.

PRACTICAL APPLICATIONS

SFE could fractionate grape seed oil and afford various grades of oil containing different proportions of fatty acids. The highest grape seed lipid yield obtained was with SC CO₂ + ethanol, making this solvent a promising and powerful one for grape seed oil extraction, showing a great advantage compared with conventional extraction methods.     

不同产地蜂胶成分含量的比较

目的：比较不同产地蜂胶成分含量,为蜂胶合理开发利用提供理论依据。方法：选择国内外7种不同蜂胶,分别测定其氨基酸、多糖、维生素B1、维生素B2、维生素C、维生素E、钙、铁、锌、硒、多酚、黄酮、对香豆素、肉桂酸、阿替匹林—C等成分含量。结果：所测蜂胶氨基酸含量差异较大,最低为26.6mg/100g,最高为164.08 mg/100g;多糖含量差异也较大,最低为0.07mg/g,最高为6.88 mg/g;维生素B1含量较维生素B2低;维生素C含量较稳定;维生素E含量波动较大,最低4.3mg/100g,最高67.4 mg/100g;钙、锌含量相对较稳定,铁、硒含量差异较大,最高可达到2—3个数量级;所测蜂胶多酚、黄酮类物质、对香豆素等含量均较为丰富;肉桂酸含量差异较大;巴西蜂胶阿替匹林—C含量最高,为2.30%,部分国产蜂胶也检测出一定量的阿替匹林—C。结论：不同产地蜂胶有效成分含量差异较大,可能会对其生物活性产生一定影响。