Extraction yield of isoflavones from soybean cake as affected by solvent and supercritical carbon dioxide

Soybean cake has been shown to be a rich source of isoflavone and can be produced during processing of soybean oil as byproduct. The objectives of this study were to compare the extraction yield of isoflavone from soybean cake by solvent and supercritical carbon dioxide, and study the conversion of isoflavone glucosides to the biologically active aglycone by employing β-glucosidase. Results showed that with supercritical carbon dioxide extraction, a maximum yield of malonylglucoside and glucoside was generated at 60 °C and 350 bar, while a high level of acetylglucoside and aglycone was produced at 80 °C and 350 bar. Supercritical carbon dioxide extraction resulted in a lower yield of total isoflavone than solvent extraction, but the former was more applicable to extraction of acetylglucoside and aglycone, and the latter to malonylglucoside and glucoside. A peak level of aglycone was attained from conversion of isoflavone glucoside by β-glucosidase at 55 °C, pH 5, concentration 50 U/ml and incubation time of 2 h.     

超临界CO2萃取燕麦油的技术研究及其脂肪酸分析

利用正交实验设计,研究超临界CO2从燕麦麸皮中萃取燕麦油的工艺参数,且用GC-MS分析了燕麦油的脂肪酸组成,为开发功能性油脂提供一定的理论参数.实验结果表明,最佳工艺参数是压力15MPa、温度35℃、时间3h.所得燕麦油澄清透明,呈现金黄色,具有特殊的麦香味.其脂肪酸主要有棕榈酸、硬酯酸、反-9-十八碳烯酸、亚油酸、亚麻酸、顺-9-十八碳烯酸,相对含量分别为15.30%、2.24%、44.84%、33.81%、1.69%和2.12%,而且不饱和脂肪酸占82.26%.     

Purification and characterisation of antibacterial peptide-containing compound derived from palm kernel cake

Palm kernel cake (PKC), the most useful by-product resulted from palm kernel oil production. In this study, PKC-derived protein product was found suitable for use as an antimicrobial agent with potent antibacterial activity, particularly against Bacillus species, after enzymatic hydrolysis with alcalase. The hydrolysate was further purified by gel filtration chromatography. The purified fraction was found to have 14.63 ± 0.70% (w/w) protein, a molecular mass of 2.4 kDa and low hemolytic activity (<50% hemolysis of human erythrocytes at concentration of 1000 μg/ml). The presence of lysine and the major component lauric acid derivative, as indicated by electrospray ionisation-mass spectrometry (ESI-MS) direct infusion and nuclear magnetic resonance (NMR) spectroscopy, may have contributed to the antibacterial effect of purified PKC fraction. This study suggests that the antibacterial PKC compound may be not a pure peptide but instead a peptide-containing compound high in lauric acid derivative.     

超临界CO2萃取樱桃仁油及GC-MS分析

以樱桃仁为原料,利用超临界CO2流体萃取樱桃仁油,在单因素试验的基础上,采用Box-Behnken设计方法,研究萃取压力、萃取时间、萃取温度及其交互作用对樱桃仁油得率的影响,确定了超临界CO_2流体萃取樱桃仁油的最佳工艺参数,并利用气相色谱-质谱(GC-MS)分析了樱桃仁油的脂肪酸组成。结果表明,超临界CO_2流体萃取樱桃仁油的最佳工艺参数为萃取压力43 MPa、萃取时间199 min、萃取温度44℃、装料量35 g,在此条件下,樱桃仁油的得率为(51.41±0.45)%。GC-MS分析表明,樱桃仁油的主要脂肪酸成分是油酸(52.55%),亚油酸(29.93%),棕榈酸(9.52%),硬脂酸(3.93%)。     

Supercritical carbon dioxide extraction of seed oil from Opuntia dillenii Haw. and its antioxidant activity

Supercritical carbon dioxide extraction of seed oil from Opuntia dillenii Haw. and its antioxidant activity were investigated in this study. The effects of main operating parameters including extraction pressure, temperature, time and CO₂ flow rate on the extraction yield of seed oil were studied. The maximum extraction yield of 6.65% was achieved at a pressure of 46.96 MPa, a temperature of 46.51 °C, a time of 2.79 h and a CO₂ flow rate of 10 kg/h. The chemical composition of the seed oil was analysed by GC–MS. The main fatty acids were linolenic acid (66.56%), palmitic acid (19.78%), stearic acid (9.01%) and linoleic acid (2.65%). The antioxidant activity of seed oil was assessed by means of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay and β-carotene bleaching test. Both methods demonstrated notable antioxidant activity of seed oil, which is nearly comparable to the references ascorbic acid and butylated hydroxytoluene (BHT). The antioxidant activity of the seed oil was also found to be concentration-dependent.     

超临界二氧化碳萃取猕猴桃籽油的研究

采用超临界萃取方法，以二氧化碳作为溶剂，从猕猴桃籽中提取猕猴桃籽油，着重探讨了萃取压力、萃取温度、萃取时间等参数对萃取结果的影响，并确定了最佳的工艺条件；在此条件下萃取效率可达97％以上，与传统工艺进行比较，超临界萃取是一种优异的提油方法。     

Supercritical carbon dioxide extraction of oil and α‐tocopherol from almond seeds

The objective of this study was to extract oil and tocopherols from almond seeds using supercritical carbon dioxide and to compare this extraction with a traditional solvent method. Oil and tocopherol extraction rates were determined as functions of the pressure (350–550 bar), temperature (35–50 °C) and CO₂ flow rate (10–30 kg h⁻¹), using a 10‐l vessel. The effects of matrix particle size on extraction yield were also studied and it was demonstrated that extraction yield is greatly influenced by particle size. Maximum recovery was obtained in the first 2–3 h of extraction at a pressure of 420 bar, a temperature of 50 °C and a flow rate of 30 kg h⁻¹ CO₂. These results suggest that the elevated initial oil and tochopherol solubility is related to the increased proportion of fatty acids in the initial extract. The results were compared with those obtained when hexane/methanol was used as a solvent. Copyright © 2005 Society of Chemical Industry     

Supercritical carbon dioxide extraction of volatile oil from Italian coriander seeds

Supercritical CO₂ fluid extraction of the volatile oil from Italian coriander seeds was carried out under different conditions of temperature (40 and 50 °C), pressure (90, 100 and 150 bar), mean particle size (0.4, 0.6 and 0.8 mm) and CO₂ flow rate (0.79, 1.10 and 1.56kg/h) in order to evaluate their influence on the yield and composition of the volatile oil. Hydrodistillation with the same mean particle sizes was performed and used as a comparative method. The best supercritical fluid extraction conditions were found to be 90 bar, 40 °C, 1.10 kg/h and 0.6 mm. The chemical composition of each supercritical fluid extraction sample was analysed by GC and GC–MS and the global composition was compared with that obtained by hydrodistillation. The dominant components were linalool (65–79%), γ-terpinene (4–7%), camphor (3%), geranyl acetate (2–4%), α-pinene (1–3%), geraniol (1–3%) and limonene (1–2%). Moreover, supercritical fluid extraction samples were collected at specific intervals of amount of CO₂ consumed, during each extraction, and the contribution of the main volatile components from each sample, for the global volatile compositions, was evaluated. In general, the first sample of each extraction contained up to 50% of the mass of each component.     

超临界CO2流体萃取打瓜籽油的工艺研究

采用超临界CO2流体从打瓜籽中萃取打瓜籽油。以打瓜籽油得率及亚油酸提取量为指标,采用单因素试验研究打瓜籽粉碎粒度、萃取压力、萃取温度、萃取时间对超临界CO2流体萃取打瓜籽油的影响。通过正交试验得到最佳萃取条件为:粉碎粒度80目,萃取压力30 MPa,萃取温度40℃,萃取时间20 min。在最佳萃取条件下,打瓜籽油得率为42.42%,亚油酸提取量为185.77 mg/g。     

Supercritical carbon dioxide extraction of lycopene: A review

Lycopene is a powerful antioxidant and potential high-value compound for the nutraceutical and pharmaceutical sectors. Its low solubility in water and high solubility in toxic organic solvents has led to a number of studies being carried out on using supercritical carbon dioxide to extract lycopene, with a majority of the studies focusing on extraction from tomatoes or tomato-derived preparations. Parameters such as temperature, pressure, flow rate, extraction time, sample moisture content and sample particle size influence the yield of lycopene via the exertion of different mechanisms. The use of co-solvents and modifiers can greatly enhance the lycopene yield beyond optimization of the parameters previously mentioned, while the co-extraction method offers a new way of enhancing lycopene yields. The scope of this review covers the effects of various parameters on lycopene extraction by supercritical carbon dioxide.     

超临界流体CO2萃取南瓜籽油的初步研究

以超临界流体CO2萃取技术对南瓜籽中的油脂提取进行了初步研究.研究了不同物料粒度、萃取压力、萃取温度、萃取时间及CO2流量对南瓜籽油萃取率的影响.     

Extraction of lipids from cherry seed oil using supercritical carbon dioxide

 Cherry seeds (Prunus avium L.) were extracted with compressed carbon dioxide at 313 K and 333 K in the pressure range 18–22 MPa. The influence of superficial velocity was also analysed using values of 0.02, 0.06 and 0.08 cm/s. The extraction yield was increased by a reduction in particle size. The physical and chemical characteristics of the oil were determined. The results, in terms of free fatty acids and sterol compositions, were compared with those obtained when hexane was used as solvent. Other physical and chemical characteristics were also compared with refined hexane-extracted oil. Received: 29 February 2000 / Revised version: 19 April 2999     

Rheological behaviour of aerated palm kernel oil/water emulsions

The interactions between emulsion droplets containing solid fat are important for the rheology and functionality of the emulsion as a whole, particularly for aerated emulsion systems where partial coalescence plays a role in the overall structure of the product. In this study, the interactions between emulsion droplets appeared to be sensitive to the relative amounts of solid fat and liquid oil, thus changing the rheology of the whole system. Incorporation of air had a major effect on these interactions as it appeared to force the emulsion to adopt a stronger structure by encouraging partial coalescence. The rheological behaviour of a non-aerated emulsion and an aerated emulsion was compared. Non-aerated samples did not show major changes in viscosity with increasing temperature. In contrast, the aerated emulsion seemed to be considerably more temperature sensitive, showing a dramatic increase of viscosity as the temperature was increased above a critical value. The effect of temperature ramp rates was investigated. Higher temperature ramp rates resulted in delayed changes in viscosity. The phase behaviour of the fat is both time and temperature dependent; therefore, a faster temperature ramp means that a higher temperature could be reached before critical phase changes in the fat could take place. The rheological behaviour of the emulsions was also dependent on the shear rate applied during the experiment.     

大蒜超临界CO2萃取物成分分析

对大蒜超临界CO2萃取物进行了GC-MS分析，借助NTST98.L数据库的质谱图数据，参考文献和人工解析对其中的20多种组分进行，定性鉴定，并利用峰面积归一化法进行了初步定量。大蒜风味物的GC-MS分析表明：大蒜超临界CO2萃取物中含有许多水蒸汽蒸馏蒜油中没有检测到的风味成分，其中最显蔷的是蒜素色谱分析中脱水衍生的3-乙烯基-l，2-二硫杂-4-环已烯(3．96％)及3-乙烯基-1．2-二硫杂-5-环己烯(17．88％)，此外还含有少量的亚油酸及油酸。     

Supercritical carbon dioxide fluid extraction of Hibiscus cannabinus L. seed oil: A potential solvent-free and high antioxidative edible oil

The supercritical fluid extraction (SFE) trends and antioxidant activities of Hibiscus cannabinus seed oils were studied. SFE results indicate that extraction pressure is the major factor determining the oil yield. In comparison, classic Soxhlet extraction (SOX/L) yielded higher oil content than SFE (P < 0.05). However, no significant differences in oil content were observed in SFE at 600 bars/80 °C, rapid Soxhlet extraction (SOX/S) and conventional ultra-sonic assisted solvent extraction (SONIC) (P > 0.05). Antioxidant activities of H. cannabinus seed oils were compared with 7 types of commercial edible oils. DPPH scavenging activity test indicated that H. cannabinus seed oil extracted by SFE at 200 bars/80 °C possessed the highest antiradical activity whereas beta-carotene bleaching (BCB) assay revealed that all H. cannabinus seed oils (except for SFE at 400 bars/80 °C and 600 bars/80 °C) exhibited higher antioxidant activity than all commercial edible oils (P < 0.05). Thus, SFE – H. cannabinus seed oil may serve as an excellent source of solvent-free edible oil with high antioxidant properties.     

微波预处理-超临界CO_2萃取牡丹籽油的工艺研究

为实现超临界CO2萃取技术高效萃取牡丹籽油,先利用微波技术对原料进行预处理,再利用超临界CO2萃取技术萃取牡丹籽油。固定微波功率800 W,采用正交实验得到微波预处理最佳条件为:微波预处理时间40 s,原料粉碎粒度100目,原料水分含量6.2%。采用响应面法对超临界CO2萃取工艺条件进行优化分析,得到最佳工艺条件为:CO2流量25 kg/h,萃取压力33 MPa,萃取温度40℃,萃取时间100 min。在最佳条件下,牡丹籽油萃取率高达98.55%。与未经微波预处理直接进行超临界CO2萃取所得牡丹籽油相比,水分及挥发物含量降低,酸值和过氧化值升高。     

Supercritical carbon dioxide extraction of carrot fruit essential oil: Chemical composition and antimicrobial activity

Isolation of carrot fruit (Daucus carrota L., cultivar “Chanteney”) essential oil by supercritical carbon dioxide was investigated from the pretreatment of herbaceous matrix and extraction conditions to the chemical composition of obtained extract and its antimicrobial activity. The qualitative and quantitative analyses of the supercritical extract, as well as of the essential oil obtained by hydrodistillation, were done by GC/FID and GC/MS methods. Antimicrobial properties of both samples were investigated against ten species of microorganisms. Experimental results showed that the particle size had no influence on the extraction process. The highest yield was obtained at 40 °C and 10 MPa. The main component of the supercritical extract, as well as of the essential oil was carotol. The supercritical extract was characterized by the presence of heavier molecular weight compounds, while some lighter compounds, e.g. pinenes, were not detected. The supercritical extract and the essential oil were the most effective against Gram-positive bacteria.     

香榧子油超临界CO2萃取工艺及脂肪酸成分分析

为优化超临界CO2萃取香榧子油的工艺条件,研究了萃取时间、萃取温度及萃取压力对香榧子油得油率的影响。在单因素实验的基础上利用正交实验进行工艺优化,结果表明,最适萃取工艺条件为:萃取时间4h、萃取温度50℃、萃取压力45MPa,在该萃取条件下的得油率为94.57%。利用GC分析香榧子油脂肪酸组成,共鉴定出18个组分,不饱和脂肪酸含量为87.28%,其中亚油酸、油酸和二十碳三烯酸含量分别为42.02%、32.14%和9.80%。     

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.     

超临界CO2流体萃取米糠油研究

通过超临界CO2流体萃取米糠油研究,总结萃取压力、萃取温度、萃取时间和物料水分含量对米糠出油率影响。结果表明,最适宜萃取条件为:萃取压力30 MPa、萃取温度45℃、萃取时间80 min、物料水分含量为5％～6％,出油率达14．32％;同时测定超临界CO2流体萃取米糠油中脂肪酸甘油酯组成,得出油酸甘油酯、亚油酸甘油酯和棕榈酸甘油酯占总脂肪酸甘油酯90％以上,其中,油酸甘油酯和亚油酸甘油酯占总脂肪酸甘油酯70％以上;通过超临界CO2法与压榨法比较,超临界CO2流体法萃取米糠油不饱和脂肪酸含量较高,理化指标也优于压榨法,因萃取温度低,防止提取过程中油脂氧化,因此超临界CO2流体萃取是一种较好提取米糠油方法。