超临界CO_2萃取香料精油的研究

本文对熏衣草、百里香、野百里香和迷迭香４种香料单独或两种香料混合超临界ＣＯ２萃取和分级分离香料精油的工艺可行性，以及采用ＧＣ，ＧＣ－ＭＣ对萃取物的主要成分分析进行了初步研究。从两种香料混合物中革取所获产率等于从每种香料所获产率之平均值，混合萃取明显提高精油和树脂两种产品的分离效率，两种香料混合物的萃取物所含的主要成分与两种香料单独萃取的成分相同，但浓度有明显差别。     

不同方法提取姜精油的对比分析

介绍应用水蒸气蒸馏法和超临界CO2萃取法提取姜精油的工艺条件及各自主要成分的分析结果,发现超临界CO2萃取工艺得到的姜精油含有体现生姜独特风味的姜辣素,如以色谱峰面积归一法计算,CO2萃取法含量最高的姜醇占26.00%,且含量与萃取时间有关,而水气法萃取物不含姜醇。既说明超临界萃取有特色和优势,也为超临界提取姜精油操作时间的确定提供参考。     

超临界CO2萃取甲鱼油的研究

用超临界CO2 萃取技术从甲鱼中提取分离甲鱼油 ,着重探讨了影响萃取率的主要因素 ,并同传统的溶剂萃取法进行比较 ,分析了两种萃取方法得到甲鱼油的脂肪酸组成。结果表明 :超临界CO2 萃取甲鱼油的适宜工艺条件为 :2 0MPa ,4 5℃ ,CO2 流量为 1.8kg/ (h·g)原料 ,萃取时间为 6h ;超临界CO2 萃取法萃取率 (98.1% )明显高于乙酸乙酯萃取法 (85 .2 % ) ,两种方法所得到的甲鱼油主要脂肪酸组成基本一致 ,甲鱼油中含有的不饱和脂肪酸高达 70 %以上 ,其中多不饱和脂肪酸含量大于 2 6 %。     

辣木籽油两种提取方法的比较及研究

以辣木籽为原料,以石油醚热提法和超临界CO2萃取法对其中精油成分、食用油脂成分进行提取分离,得到2个辣木籽油样品。采用同时蒸馏萃取和气相色谱/质谱法对各样品的挥发性成分进行了分离鉴定。结果表明:辣木籽油主要成分多为各类脂肪酸类衍生物,富含反油酸、棕榈酸、油酸乙酯、硬脂酸。     

超临界CO2和有机溶剂提取艾蒿叶中风味物质的研究

采用有机溶剂提取法和超临界CO2 流体萃取法分别提取艾蒿叶风味物质 ,并用气相———质谱联用仪检测了提取的风味物质的化学成份。结果表明 ,采用不同方法得到的提取物的化学成分有所不同 ,超临界CO2 萃取物的化学成份较少 ,艾蒿叶精油纯度高 ,是提取艾蒿叶风味物质较优的工艺方法。     

利用超临界流体萃取制备百里香精油的工艺研究

介绍了超临界CO2萃取百里香精油的提取分离技术工艺,重点研究了超临界CO2萃取压力、温度、时间对出油率的影响,并且应用正交实验优化出较佳的工艺参数:CO2萃取压力为:25MPa;温度:40℃;时间:4h;流量:25L/min。由超临界CO2提取精油的出油率高达4.22%。     

超临界CO2流体萃取五味子精油及精油成分区域性差异研究

采用超临界CO2萃取法(SCDE)萃取来自四地的五味子,探讨其木质素含量的区域性差异。超临界CO2萃取提取工艺条件为:萃取釜压力18MPa,萃取温度40℃,萃取时间90min,解析釜压力6MPa。萃取结果采用高效液相色谱法(HPLC)进行分析,以得油率和五味子木质素含量为各地五味子的品质评价指标,并与有机溶剂法萃取所得木质素含量作对比。对于提取五味子精油,超临界CO2萃取法的精油品质明显优于有机溶剂萃取法。四地五味子中各种木质素的含量区域性差异显著,且吉林长白山北五味子的得油率和总木质素含量最高。     

超临界CO2萃取天然香辛料精油研究进展

近年来,超临界流体萃取在我国发展极其迅速,应用领域越来越广.本文就超临界CO2萃取的基本原理、超临界CO2萃取天然香辛料精油的工艺、夹带剂的选择与使用、精油组分的分析方法和影响超临界CO2萃取香辛料精油的工艺因素:原料粒度、萃取压力、萃取温度、CO2流量、提取时间等进行了综述,并展望了超临界CO2萃取香辛料精油的应用前景.     

超临界CO2提取花椒精油的研究

为采用超临界CO2提取花椒精油,采用正交实验法对花椒精油的超临界CO2提取工艺进行优化,以精油的得率为指标,考察萃取压力、温度、时间对精油得率的影响.得到的最佳工艺条件为:萃取压力30 MPa, 萃取温度40℃,萃取时间130 min,花椒精油得率10.81%.超临界CO2提取花椒精油得率高,提取时间短,是提取花椒精油的适宜方法.     

提取姜油树脂的工艺参数及最佳因素水平组合的研究

目前提取姜油树脂的主要方法有:溶剂浸提法、压榨法、流体CO2浸提法和超临界CO2萃取法。超临界CO2萃取法分离物质是一种新的分离技术,有着良好的前景,它能使要分离的物质提高收率、提高品质。影响超临界CO2萃取姜油树脂的主要因素有萃取压力、萃取温度、萃取时间和萃取时CO2的流量。通过实验,我们确定了超临界CO2萃取姜油树脂的工艺参数,得出超临界CO2萃取姜油树脂的最佳因素水平组合是:A2B1C3D1,即萃取压力25MPa;萃取温度40℃;萃取时间2.5h;CO2泵频率15Hz。从极差R值可知,4个因素对超临界CO2萃取姜油树脂萃取率影响的主次顺序是:A>B>C>D,即萃取压力>萃取温度>萃取时间>CO2气体的流量,压力对超临界CO2萃取姜油树脂的影响最大。     

Central composite design for the optimization of supercritical carbon dioxide fluid extraction of fatty acids from Borago officinalis L. flower

Abstract: In the present study, fatty acids and essential oils of the flower of borage (Borago officinalis L.) were obtained by supercritical carbon dioxide fluid extraction under different conditions. The extracts obtained were compared to oils of borage flower oil isolated by hydrodistillation. The obtained oils were analyzed by gas chromatography mass spectrometry. The compounds were identified according to their retention indices and mass spectra. The experimental parameters of supercritical fluid extraction (SFE) were optimized using a central composite design after a full factorial experimental design. Extraction yields based on SFE varied in the range of 0.02% to 1.96% (w/w), and the oil yield based on the hydrodistillation was 0.05% (v/w). The optimum conditions of SFE were obtained at a pressure of 350 atm, a temperature of 65 °C, a methanol modifier volume of 100 μL, and static and dynamic extraction time of 10 min. Main components of the extracts under optimum SFE conditions were palmitic acid, linoleic acid, γ‐linolenic acid, and oleic acid. The results indicated that by using the suitable extraction conditions, SFE is more effective than the conventional hydrodistillation method in the extraction of fatty acids and the preservation of its quality. Practical Application: SFE is a good technique for the extraction of oils from plants. The extraction yields by SFE are more than the conventional method. SFE is used on a large scale for production of essential oils and pharmaceutical products from plants.     

Comparison of essential oils of clove buds extracted with supercritical carbon dioxide and other three traditional extraction methods

Supercritical fluid extraction (SFE) of essential oil from clove buds with CO₂ was explored. The effect of different parameters, such as temperature (30 °C, 40 °C, 50 °C), pressure(10 MPa, 20 MPa, 30 MPa) and particle size (three degree index), on the extraction yield and the content of eugenol in extracts was investigated using three-level orthogonal array design. The experimental results show that the temperature has the largest effect on the eugenol content of the extracts, and particle size has the maximum effect on the oil yield. The essential oil of 19.56% yield, in which the maximum content of eugenol in extracts is 58.77%, can be extracted from clove buds at pressure of 10 MPa and temperature of 50 °C. Essential oil of clove buds obtained by SFE, hydrodistillation, steam distillation and Soxhlet extraction were further analyzed by gas chromatography/mass spectrometric detection to compare the extraction methods. Twenty three compounds in the clove oils have been identified, showing that the composition of the clove oil extracted by different methods is mostly similar, whereas relative concentration of the identified compounds is apparently different. General characteristics of the clove oils obtained by different methods were further compared, and SFE is considered as the optimum process among the four processes for obtaining clove oil with high quality.     

Extraction of Mentha spicata L. Volatile Compounds: Evaluation of Process Parameters and Extract Composition

Mint (Mentha spicata L.) is a European aromatic plant, with its essential oil used in food, pharmaceutical and cosmetic industries. Supercritical fluid extraction (SFE) is important for natural products, because it is residue free and preserves thermolabile compounds and product characteristics. The aim of this work was to obtain mint essential oil by sub-/supercritical extraction, with and without modifier and in different operational conditions, by hydro-distillation and by Soxhlet with different solvents. The results indicated the SFE highest yield (2.38% w/w) was obtained at 50 °C and 300 bar, with the crossover of yield isotherms occurring between 140 and 170 bar. When using a cosolvent for SFE, the ethanol showed the highest yield, compared to ethyl acetate. The mint essential oil was rich in compounds with therapeutic activities and several substances of industrial interest, such as carvone, cineol, and pulegone, presenting also good antioxidant activity performance.     

Comparative evaluation of the composition of vegetable essential and fixed oils obtained by supercritical extraction and conventional techniques: a chemometric approach

We compared by a chemometric approach the composition of essential (EO) and fixed (FO) oils previously obtained from several vegetable matrices by supercritical CO₂ extraction (CO₂-SFE) and conventional techniques (n-hexane in a Soxhlet apparatus and hydrodistillation). A multivariate approach, by determining the principal components analysis (PCA) applied to data of FO fatty acids and EO volatile compounds, generally indicated that the vegetable oils extracted with CO₂-SFE tightly clustered with those obtained by conventional methods. The graphical distances calculated in the PCA plots between the score of each SFE oil and the corresponding conventional oil revealed that the CO₂-SFE FO and EO profiles were quite similar to conventional oils, with the additional benefit of not having unwanted traces of solvent. SFE FO were more similar to conventional oils than SFE EO (mean values of calculated graphical distances were 0.83 and 1.46 for FO and EO, respectively). Our results strongly corroborate the role of CO₂-SFE as a suitable, environmentally safe and efficient method alternative to the traditional ones for the extraction of natural vegetable oils for food and pharmaceutical applications.     

Supercritical fluid extraction of tea seed oil and its comparison with solvent extraction

Supercritical fluid extraction (SFE) of tea seed oil was performed to study the effects of various parameters such as pressure, temperature, extraction time (dynamic) and modifier (ethanol) on the yield and composition of the oil. The results were also compared with those obtained by Soxhlet extraction, ultrasonic extraction, and DGF (Deutsche Gesellschaft für Fettwissenschaft) standard method B-I5 (87) in lab conditions. The yield of tea seed oil obtained using SFE was similar to or higher than the other methods. The results from SFE showed that the modifier and pressure have significant effects on the extraction efficiency. The oil extracted by SFE in the absence of modifier was clearer than the oils obtained in other conditions. The fatty acid composition of each extract was determined by gas chromatography. Palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2) and gadoleic (C20:1) fatty acids were observed in the oil samples. Since it contains high-unsaturated fatty acids (UFA) and low saturated fatty acids (SFA), edible tea seed oil is also relatively healthy.     

Application of response surface methodology and central composite design for the optimisation of supercritical fluid extraction of essential oils from Myrtus communis L. leaves

Essential oils of Myrtus communis L. leaves were obtained using supercritical fluid extraction (SFE) and hydrodistillation methods. The experimental parameters of SFE such as pressure, temperature, modifier volume, static and dynamic extraction time were optimised using a central composite design after a 2ⁿ⁻¹ fractional factorial design. The chemical compositions of the SFE extract were identified by GC–MS and determined by GC–FID. The major components of essential oils obtained by hydrodistillation were α-pinene (31.8%), 1,8-cineole (24.6%), limonene (14.8%), linalool (8.3%) and α-terpinolene (4.8%). However, by using the supercritical carbon dioxide in optimum conditions, only three components represented more than 85% of the extract. Therefore, by using the proper SFE conditions, the supercritical extraction is more selective than the conventional hydrodistillation methods. The oil yields based on the hydrodistillation was 0.47% (v/w). Extraction yields based on the SFE varied in the range of 0.5–6.3% (w/w) under different conditions.     

Flavour compounds of Lavandula angustifolia L. to use in food manufacturing: Comparison of three different extraction methods

Sixty compounds of Lavandula angustifolia L. cultivated in Friuli Venezia Giulia (North-East Italy) were identified and quantified by GC-MS and GC-FID from essential oils obtained by means of hydrodistillation, and from extracts obtained by supercritical CO₂ extraction (SFE) and ultrasound-assisted extraction (US). Using absolute calibration, a true quantification of 1-8 cineol, camphor, linalool, linalyl acetate and β-caryophyllene was carried out. The best extracts, in terms of amount of isolated compounds, flavour quality and stability were those obtained with SFE. Sonication performed at low amplitude for 5 min offered respect to high amplitude a promising alternative to hydrodistillation as a source of lavender flavouring ready to use for alcoholic beverages or/and confectionery products.     

Essential oil composition and antimicrobial activity of Origanum majorana L. extracts obtained with ethyl alcohol and supercritical carbon dioxide

Volatile components of marjoram (Origanum majorana L.) essential oil obtained by hydrodistillation and extracts obtained by solvent extraction with ethyl alcohol and supercritical fluid extraction (SFE) were investigated. The compositions of volatile compounds in essential oil, ethanolic and SFE extracts were determined by GC and GC–MS. The antimicrobial properties of marjoram solvent extracts were investigated with microbiological tests against food borne fungi and bacteria strains. Extracts obtained by SFE at high pressure and temperature showed significantly stronger antimicrobial properties in comparison to the slight inhibitory effects of the ethanolic extract. The results support the notion that extracts obtained by SFE might have a role as flavourings and natural colourants as well as use as preservatives in food and cosmetic systems.     

白豆蔻精油超临界CO2萃取工艺优化及挥发性成分分析

以白豆蔻为原料,利用水蒸气蒸馏（SDE）法和超临界流体萃取（SFE）法提取白豆蔻精油。以萃取率为评价指标,采用单因素试验及正交试验优化萃取工艺,并采用气质联用（GC-MS）法分析两种提取方法所得白豆蔻精油的组成。结果表明,最佳萃取工艺条件为：萃取压力25 MPa、萃取温度50 ℃、CO2流量14 mL/min、提取时间4.0 h。在此优化条件下,SFE提取白豆蔻精油得率为6%,为SDE提取精油的1.5倍。GC-MS分析结果表明,共检出挥发性化合物158种,其中SDE和SFE提取精油中分别检出97种、111种,独有化合物分别有47种、61种,共有化合物有50种。两种提取方法所得精油的组成相似,主要成分有桉叶油醇、α-蒎烯、4-异丙基甲苯、顺式十五烯酸、棕榈酸等,但含量差异较大。结果表明SFE是提取白豆蔻精油的有效方法。     

白果油的提取及脂肪酸组成分析

以白果为原料,用索氏提取和超临界萃取(SFE)两种方法从中提油,比较了不同提取方法对油得率的影响,测定了索氏提取油的理化特性,用气相色谱法和高效液相色谱法分别测定两种方法提取油的脂肪酸组成和VE的含量。结果表明,与常规植物油脂理化指标相比,白果油比重偏高,碘值较大,说明白果油不饱和程度较高;气相色谱分析结果表明两种方法提取的白果油中均含有多种不饱和脂肪酸,且不饱和脂肪酸含量均大于91%,而其中亚油酸和油酸的总含量均大于75%,索氏提取和超临界萃取的油中VE的含量分别为670 mg/kg和610 mg/kg。