超临界萃取花生中主要成分的研究

采用超临界CO2萃取花生油脂中主要成分,研究了萃取压力、萃取温度、萃取时间和夹带剂用量等对萃取率的影响。结果表明,在CO2流量为10~12 L/h的前提下,最佳工艺条件是:萃取温度45℃,萃取压力30 MPa,萃取时间2.0 h,夹带剂用量20 mL。在此条件下,花生油脂的萃取率可达50.39%。影响提取率的主次因素为萃取压力萃取时间萃取温度夹带剂用量。     

超临界CO2萃取对牛蒡子油脂及拉帕酚F的影响

研究超临界CO_2萃取对牛蒡子油脂及拉帕酚F的影响。在萃取温度55℃、分离Ⅰ压力9 MPa、分离Ⅰ温度50℃的萃取条件下,对比分析8、20、40、60 MPa的萃取压力对牛蒡子萃取效率的影响。通过GC-MS法及相关理化指标测定分析,研究不同萃取压力对牛蒡子油脂中脂肪酸的组成、理化指标等质量的影响。通过单因素试验,对超临界CO_2萃取拉帕酚F的影响因素进行了研究。不同的萃取压力对牛蒡子的萃取效率有明显差异,萃取压力越高,拉帕酚F(LAF)和油脂萃取效率越高,而且收率也相应提高,分离Ⅰ压力对LAF收率具有较大的影响;不同萃取压力下的牛蒡子油脂脂肪酸组成存在显著差异。从理化指标上看,高压萃取条件有助于降低牛蒡子油脂的酸值和过氧化值,提高油脂的品质。与传统方法和超临界CO_2传统压力萃取相比,高压超临界CO_2萃取更有利于牛蒡子油脂及LAF的萃取,为牛蒡子的后续研究及开发提供研究基础。     

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.     

超临界CO_2萃取辣椒油的工艺条件优化研究

以三峡库区种植的辣椒为原料,采用超临界CO2萃取技术,从辣椒中提取辣椒油,考察了萃取温度、萃取压力和萃取时间对辣椒油萃取率的影响。结果表明,萃取温度对辣椒油的萃取率影响最大,其次是萃取压力,萃取时间影响最小;超临界CO2萃取辣椒油的最适宜条件为,萃取温度40℃,萃取压力10 MPa,时间75 min,其萃取率为9.37%;超临界CO2萃取技术应用于辣椒油的提取具有工艺简单、操作安全、能耗低、无毒、萃取剂易回收、萃取率和产品纯度高等优点。     

超临界CO2萃取辣椒油的工艺条件优化研究

以三峡库区种植的辣椒为原料,采用超临界CO2萃取技术,从辣椒中提取辣椒油,考察了萃取温度、萃取压力和萃取时间对辣椒油萃取率的影响。结果表明,萃取温度对辣椒油的萃取率影响最大,其次是萃取压力,萃取时间影响最小;超临界CO2萃取辣椒油的最适宜条件为,萃取温度40℃,萃取压力10 MPa,时间75 min,其萃取率为9.37%;超临界CO2萃取技术应用于辣椒油的提取具有工艺简单、操作安全、能耗低、无毒、萃取剂易回收、萃取率和产品纯度高等优点。     

超临界乙醇萃取蒽的实验研究

以乙醇为超临界萃取剂,采用恒容升温法研究了超临界乙醇对煤焦油中重要组分蒽的萃取效果,探究了温度和压力对萃取效果的影响。结果表明,在270~275℃,萃取压力为15.5 MPa左右时,萃取效果达到66%。实验表明,温度和压力对超临界乙醇萃取蒽有明显的影响。     

响应曲面法优化超临界CO_2萃取猕猴桃籽油条件

以猕猴桃籽为试验原料,在单因素试验的基础上,采用响应曲面分析法建立了超临界CO2萃取猕猴桃籽油萃取率的二次多元回归方程,探讨了压力、温度、CO2流量等关键因素对萃取率的作用规律。结果表明,萃取压力、温度、CO2流量对萃取率影响显著,萃取压力和温度交互效应影响显著。根据萃取率回归方程对猕猴桃籽油的超临界萃取工艺参数进行了优选,最优工艺参数为:压力31.7 MPa,温度40.2℃,CO2流量27.4 kg/h,该条件下萃取率高达32.57%,与试验值31.24%仅有4.5%的误差,证实了该方程的预测值与试验值之间具有较好的拟合度。超临界CO2萃取的猕猴桃籽油与己烷提取的油脂在脂肪酸组成上没有显著差别。     

超临界CO2萃取烟草中茄尼醇

研究了萃取时间、解析温度、萃取压力等因素对超临界CO2萃取烟草中茄尼醇萃取率的影响。结合皂化等预处理措施,并通过正交实验得到了提取茄尼醇的最佳工艺条件,即以体积分数90%的乙醇为夹带剂,在萃取压力为35 MPa、萃取温度为50℃、解析温度为40℃时,萃取3 h后,产品茄尼醇质量分数为40.14%,萃取率达到98.53%。     

超临界CO_2萃取青皮挥发油的工艺研究

采用正交实验法对超临界CO2萃取中药青皮挥发油的最佳工艺条件进行优选。以挥发油得率为考察指标,探讨了萃取压力、萃取温度、萃取时间三因素在不同水平下对青皮挥发油得率的影响,并与水蒸气蒸馏法进行了比较。研究表明,萃取压力对挥发油得率有显著影响,萃取温度及时间影响不显著,各因素作用主次关系为:压力>温度>时间。优选得到的最佳工艺为:萃取压力25 MPa,萃取温度35℃,萃取时间1.5 h,得率为1.3197%,比水蒸气蒸馏法提高2.4倍,时间减少78.57%。超临界CO2萃取收率高、耗时短、品质好。     

超临界CO_2萃取大豆磷脂的影响因素研究

应用超临界CO2 萃取技术从大豆粗磷脂中提纯得到了质量分数为 98%的大豆磷脂。研究了萃取压力、萃取温度、萃取时间对萃取率的影响 ,3个影响因素的影响顺序为 :萃取温度 >萃取时间 >萃取压力。优化工艺条件是 :萃取压力 2 0MPa ,萃取温度 5 0℃ ,萃取时间 5h。     

Extraction of pollen lipids by SFE‐CO2 and determination of free fatty acids by HPLC

Rape bee pollen lipids obtained by petrol ether extraction (PEE) or supercritical fluid (carbon dioxide) extraction (SFE) were compared with regard to their free fatty acid (FFA) components. Optimal SFE conditions were selected by carrying out the Taguchi method with an OA9 (3³) matrix design, and are as follows: extraction pressure at 35 MPa, temperature at 45 °C, and dynamic extraction time at 90 min. The lipid yield based on PEE was 7.42 wt‐% and the extracts of the desired analytes based on SFE varied in the range of 3.23–5.58 wt‐% under different conditions. With the optimized procedure, the lipid yield was 6.09 wt‐%. The FFA in the lipids were separated with a pre‐column derivation method and 1‐[2‐(p‐toluenesulfonate) ethyl]‐2‐phenylimidazole [4,5‐f]9,10‐phenanthrene as labeling regent, followed by high‐pressure liquid chromatography (HPLC) with fluorescence detection. HPLC analysis shows that the lipids contain abundant unsaturated fatty acids (UFA) in high to low concentrations as follows: linolenic acid (18:3), oleic acid (18:1), linoleic acid (18:2), nervonic acid (24:1), and lignoceric acid (20:4). The UFA contents in the SFE extracts were higher than those after PEE. The results indicated that SFE under suitable conditions is more selective than conventional PEE with regard to lipid extraction and preservation of their quality.     

水杨酸在超临界二氧化碳中络合萃取汞离子

测试水杨酸在超临界二氧化碳中的溶解度数据,研究了水杨酸络合剂在超临界二氧化碳中萃取汞离子,分别讨论了配比、压力、温度、时间对萃取效率的影响。得到了最佳的萃取条件为20 MPa、323 K、45 min和[Hg+]:[SAL]:[PFOSANEt4]=1:200:200,在最佳萃取条件下萃取效率达到95.5%,可以进行工业领域的推广应用。水杨酸作为络合剂在超临界二氧化碳中萃取汞离子的研究未见有关报道。     

Supercritical CO2 extraction of lipids and astaxanthin from Brazilian redspotted shrimp waste (Farfantepenaeus paulensis)

Brazilian redspotted shrimp (Farfantepenaeus paulensis) waste is an important source of carotenoids such as astaxanthin and lipids with a high ω−3 fatty acids content, mainly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). In order to establish an efficient and environmental friendly recovery process, the lipids and astaxanthin were extracted from the freeze-dried redspotted shrimp waste (including head, tail and shell) using supercritical carbon dioxide. The effects of the extraction conditions of pressure (200-400 bar) and temperature (40-60 °C) on the global yield (X₀), astaxanthin extraction yield and astaxanthin concentration in the extract were evaluated. It was found that the pressure and temperature showed a very low significant effect on the lipid extraction yield using supercritical CO₂. In comparison with lipid extraction by solvents, maximum efficiency of supercritical fluid extraction achieved 64% of hexane extraction yield. On the other hand, temperature and pressure had significant effects on astaxanthin extraction yield. Thegreatest amount of extract was obtained at 43 °C and 370 bar, with 39% of recovery.     

Production of eicosapentaenoic acid byMortierella fungi

Mycelia of arachidonic acid-producing fungi belonging to the genusMortierella were found to be rich sources of 5,8,11,14,17-cis-eicosapentaenoic acid (EPA). Production of EPA by these fungi was observed only when they were grown at low temperature (6–16 C). EPA comprised 5–20% of the total extractable mycelial fatty acids in most strains tested. No significant accumulation of EPA was observed on incubation at high temperature (20–28 C), at which the other major mycelial C-20 fatty acid, arachidonic acid, was still efficiently produced. In a study on the optimization of the culture conditions for EPA production by a selected fungiM. alpina 20–17, a medium containing glucose and yeast extract as major carbon and nitrogen sources, respectively, was found to be suitable. Periodic feeding of glucose during growth of the fungus and cultivation at high temperature (20 C) during the early growth phase followed by temperature shift to 12 C were found to be effective at increasing mycelial yield and reducing cultural period, respectively. Under the optimal culture conditions, the EPA production reached 0.49 mg/ml of culture broth (29 mg/g dry mycelia). This value accounted for 13.5% of the total fatty acids in the extracted lipids. Other major fatty acids in the lipids were palmitic acid (6.0%, by weight), stearic acid (5.3), oleic acid (6.2), linoleic acid (3.0), γ-linolenic acid (3.5) and arachidonic acid (60.0). On leave from Suntory Ltd.     

Optimization of algal lipid extraction by mixture of ethyl acetate and ethanol via response surface methodology for biodiesel production

The effects of extraction time, extraction temperature, solvent to biomass ratio and solvent composition on lipid yield from lyophilized Chlorococcum sp. biomass using a mixture of ethyl acetate and ethanol (EAE), a new proposed solvent, were studied. Subsequently, the process conditions of extraction by EAE were optimized using Box-Behnken design (BBD). The results revealed that the extraction temperature had the greatest effect on lipid extraction efficiency, followed by volume ratio of ethyl acetate to ethanol (EA/E) and extraction time. The largest lipid extraction yield of 15.74% was obtained under the following extraction conditions: 40mL solvents per gram of biomass for 270 min with gentle stirring at 80 °C by EAE with an EA/E of 1.0. Furthermore, palmitic acid, stearic acid, oleic acid, and linoleic acid were the most abundant fatty acids in the lipids extracted, indicating the great potential of the proposed lipid extraction procedure for microalgae-based biodiesel production.     

尿素包合法富集分离花生四烯酸的工艺研究

为提高尿素包合法富集花生四烯酸(AA)效率,研究了降温速度、甲醇用量、尿酯比及结晶温度对花生四烯酸(AA)晶体大小、收率及纯度的影响。结果表明,当结晶温度为-7℃,降温速度为10℃/h,m(脂肪酸甲酯)∶m(尿素):v(甲醇)为1 g∶2 g∶20 mL时,AA生成大颗粒晶体。AA的质量分数w(AA)=87.0%,收率为88.7%。杂质主要为亚麻酸(w=9.21%)。产品总不饱和脂肪酸质量分数大于99%。     

Supercritical extraction of evening primrose oil: Experimental optimization via response surface methodology

Supercritical carbon dioxide (CO₂) effective extraction parameters (pressure, temperature, static extraction time, and dynamic extraction time) of oil recovery from evening primrose seeds were optimized via response surface methodology (RSM). The results of this study indicated that the linear terms of static and dynamic time and the quadratics of temperature and pressure, as well as the interactions of temperature and static time, pressure and temperature had a significant effect on the oil recovery. The optimum extraction conditions of 14.2 MPa, 47.3°C, 30 min (static extraction time) and 150 min (dynamic extraction time) were obtained. Applying the optimum conditions, a mean experimental recovery of 92.98% (triplicate experiment) was achieved, which is well compatible with the RSM‐predicted value (93.61%). The fatty acid composition of extracted evening primrose oil using supercritical CO₂ was compared with that obtained by Soxhlet method in which minor difference was observed. © 2011 American Institute of Chemical Engineers AIChE J, 2011     

Subcritical co‐solvents extraction of lipid from wet microalgae pastes of Nannochloropsis sp.

In this paper subcritical co‐solvents extraction (SCE) of algal lipid from wet pastes of Nannochloropsis sp. is examined. The influences of five operating parameters including the ratio between ethanol to hexane, the ratio of mixed solvents to algal biomass (dry weight), extraction temperature, pressure, and time were investigated. The determined optimum extraction conditions were 3:1 (hexane to ethanol ratio), 10:1 ratio (co‐solvents to microalgae (dry weight) ratio), 90°C, 1.4 MPa, and 50 min, which could produce 88% recovery rate of the total lipids. In addition, electron micrographs of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were conducted to show that the algal cell presented shrunken, collapsed with some wrinkles and microholes after SCE extraction. The main composition of total lipids extracted under the optimum conditions was TAG which represented more than 80%. And the fatty acid profile of triglycerides revealed that C16:0 (35.67 ± 0.2%), C18:1 (26.84 ± 0.044%) and C16:1 (25.96 ± 0.011%) were dominant. Practical applications: The reported method could save energy consumption significantly through avoiding deep dewatering (for example drying). The composition of the extracted lipid is suitable for the production of high quality biodiesel.     

Production of dihomo-γ-linolenic acid byMortierella alpina 1S-4

The mycelial dihomo-γ-linolenic acid content of an arachidonic acid-producing fungus,Mortierella alpina 1S-4, was found to increase, with an accompanying marked decrease in its arachidonic acid content, on cultivation with sesame oil. The resultant mycelia were found to be a rich source of dihomo-γ-linolenic acid. This unique phenomenon was suggested to be due to specific repression of the conversion of dihomo-γ-linolenic acid to arachidonic acid by the oil. After fractionation of the oil with acetone into oil and non-oil fractions, it was found that the effective factor(s) was present in the non-oil fraction. In a study on optimization of the culture conditions for the production of dihomo-γ-linolenic acid byM. alpina 1S-4, a medium containing glucose, yeast extract and the non-oil fraction was found to be suitable for the production. Under the optimal conditions in a 50-1 fermentor, the fungus produced 107 mg of dihomo-γ-linolenic acid/g dry mycelia (2.17 g/l of culture broth). This value accounted for 23.1% of the total fatty acids in the lipids extracted from the mycelia. The mycelia were also rich in arachidonic acid (53.5 mg/g dry mycelia, 11.2%). Other major fatty acids in the lipids were palmitic acid (24.1%), stearic acid (7.0), oleic acid (20.1), linoleic acid (6.6) and γ-linolenic acid (4.1). On leave from Suntory Ltd.     

Measurement of the incorporation of orally administered arachidonic acid into tissue lipids

The applicability of a stable isotope method to monitor the mixing of dietary arachidonic acid with endogenous arachidonic acid in tissue lipids was evaluated. Rats were fed octadeuterated arachidonic acid during a 20-day period, and the entry of the dietary acid into lipid esters of various tissues was examined by gas chromatographymass spectrometric (GC-MS) analysis of their fatty acids. The rats were maintained on a fat-free diet from weaning until 63 days old to enhance the ratio of the dietary acid to endogenous arachidonate. Three separate forms of eicosatetraenoic acid in the tissue lipids could be distinguished by GC-MS: octadeuterated arachidonic acid (recent dietary origin), unlabeled arachidonic acid (maternal origin) and unlabeled, 4,7,10,13-eicosatetraenoic acid (originating from palmitoleic acid). The total eicosatetraenoic acid in the tissue lipids contained about 90% arachidonate from recent dietary origin in lung, kidney, heart and fat, 70% in muscle and liver and 27% in brain. The n−7 isomer of eicosatetraenoic acid was estimated to make up 6% or less of the total eicosatetraenoic acid in lung, kidney, brain, muscle and heart tissue lipids, but it comprised around 15% of the total eicosatetraenoic acid in liver. The unlabeled arachidonic acid of maternal origin thus comprised only about 10% of the eicosatetraenoic acid in all tissues examined except muscle and brain, where it was 24% and 70% of the eicosatetraenoic acid, respectively. The relative amounts of the three forms of eicosatetraenoic acid are consistent with a limited access of dietary arachidonate to the brain tissue and with a competition between the dietary n−6 isomer and the endogenous n−7 isomer for esterification in the liver. Because most muscle mass would have formed after weaning, the high proportion of maternal arachidonate in the muscle lipids suggested that maternal arachidonate may have been displaced from other tissues to muscle, from which it equilibrated slowly with dietary arachidonate acid. The combination of deuterated arachidonic acid and GC-MS analysis thus furnished more detailed information about the composition and origin of eicosatetraenoic, acid in tissue lipid esters than that previously available from radiotracer studies or GC-MS analyses alone.