超临界CO2萃取人参挥发油工艺的研究

目的确定人参挥发油超临界CO2萃取的最佳条件。方法通过超临界CO2萃取人参挥发油的单因素试验和正交试验,研究其萃取工艺条件,考察萃取压力,萃取温度,萃取时间,CO2流量对挥发油得率的影响。结果确定了超临界萃取人参挥发油的最佳条件:萃取压力30MPa,萃取温度40℃,萃取时间100min,流量25~30L/h。结论该条件下人参挥发油(粗油)的得率为0.880%,远远高于传统索氏法提取的人参挥发油得率。     

超临界CO2萃取金柑籽油工艺

研究了超临界CO2萃取金柑籽油的最佳工艺,考察了萃取时间、萃取压力、萃取温度、CO2流量、解析压力、解析温度对萃取效果的影响。试验表明,在萃取温度为40℃、萃取压力为30 MPa、解析压力为10 MPa、解析温度为55℃和CO2流量为15 L·h^-1的条件下萃取率可达45.1%。     

姜油树脂的超临界CO_2萃取条件及其抑菌活性

采用正交试验,优化了超临界CO2萃取姜油树脂的工艺条件,在压力22 Mpa,时间15 min,温度50℃,萃取率可达5.38%。抑菌试验结果表明,姜油树脂对大肠杆菌、沙门氏菌、痢疾志贺菌、苏云金杆菌和金黄色葡萄球菌均有一定的抑制作用,抑菌最低质量浓度为0.5～1.0 mg/mL。在不同温度或不同时间紫外光照条件下,姜油树脂仍有一定的抑菌作用,表明其具有一定的光、热稳定性。     

云南大叶种茶树籽油的特征指标与脂肪酸组成研究

采用化学滴定及气相色谱等手段,对产自云南普洱的5个大叶种茶树籽油及8个常见食用植物油的特征指标(折光指数、相对密度、碘值、皂化值)和脂肪酸组成进行了对比研究.结果表明,5个大叶种茶树籽油折光指数为1.4629～1.4634;相对密度为0.9148～0.9167;碘值为859～903 g·kg-1;皂化值为189.0～1...     

超临界CO2萃取人参脂溶性成分的GC-MS分析

目的 用超临界CO2萃取人参脂溶性成分,分析并测定提取物的主要成分和含量.方法 用超临界CO2萃取人参脂溶性成分.提取物用气相色谱质谱(GC-MS)联用法进行分析鉴定.使用面积归一法测定各成分相对含量.结果鉴定了44个化合物,主要为脂肪酸和酯(34)、挥发油.结论用超临界萃取人参,可以较好的获得其脂溶性成分.     

基于籽油理化特性及脂肪酸组成的白木通种质资源评价

筛选适宜油用的白木通种质,为将其开发成新型油料作物提供参考。利用索氏提取法提取白木通种子 籽油,比较各种质的含油率,按照食用油国家标准检测籽油过氧化值、酸价、碘值和皂化值,采用气质联用（GC-MS） 系统对白木通各种质籽油脂肪酸组成进行检测分析。研究结果表明,白木通各种质含油率（36.57%~43.08%）、单果 平均含籽率（6.60%~11.51%）、种子千粒重（45.63~58.95g）和折干率（51.93%~64.28%）等经济性状指标受环境因子 的影响较大;籽油的过氧化值（0.073~0.126 mmol/kg）、酸价（0.418~1.337 mgKOH/g）、碘值（83.548~89.653 g/100g）和 皂化值（199.485~221.418 mg/g）均符合四级食用油国家标准;籽油脂肪酸成分中大多数种类为饱和脂肪酸,但不饱 和脂肪酸的含量最高,不饱和脂肪酸以油酸和亚油酸为主,二者含量达到70%左右,饱和脂肪酸以棕榈酸和硬脂酸 为主,含量在25%左右。白木通具有开发成新型油料作物的潜力,综合评价种子经济性状及籽油脂肪酸构成,白木 通种质黔通1号在研究的5份种质中表现较好,值得进一步的开发利用。     

霍霍巴籽油化学组成的测定

采用气相色谱(GC)及色谱一质谱联用(GC/MS)法测定了霍霍巴籽油化学组成。证实福建东山岛沙滩生长的霍霍巴籽粒提取的油与一般植物油大不相同,其主要成分不是通常植物油中所含的脂肪酸甘油酯而是一元不饱和脂肪酸(主要是20碳—烯酸及22碳—烯酸)和一元不饱和脂肪醇(主要是20碳—烯醇和22碳—烯醇)组成的长链脂肪酸酯。     

响应面优化超声强化超临界CO_2萃取大豆胚芽油工艺

研究超声强化超临界CO2萃取大豆胚芽油的提取工艺,通过响应面分析法优化得到的萃取条件为:萃取时间为138 min,萃取温度为37℃,萃取压力为26.3 MPa,超声波功率为300 W,超声波时间为29 min.在此条件下大豆胚芽油萃取率为87.24%左右.且大豆胚芽清油的颜色浅黄透明,香气纯正.     

超声波辅助提取苹果籽油工艺研究

通过二次回归正交旋转组合试验探讨了超声波辅助提取苹果籽油的最佳工艺条件，研究了液料比（石油醚体积与苹果籽质量之比）、提取时间、提取温度和超声波频率对苹果籽油提取率的影响。结果表明，当液料比为8，提取时间为35min，提取温度为35℃，超声波频率为60kHz时，苹果籽油提取率最高，可达到23.94％。通过与索氏提取法对比，证明超声波是一种可靠、高效的提取苹果籽油的方法。     

超临界CO_2提取茶叶中咖啡碱

用超临界萃取技术分离提取茶叶中的咖啡碱，再用CH2Cl2萃取分离，得到纯度为95．16％的咖啡碱，萃取率和得率分别为16．85％、0．55％。试验结果还表明，在一定条件下，利用超临界萃取技术能够有效地分离茶多酚和咖啡碱。     

Changes in fatty acids composition during seed growth and physicochemical characteristics of oil extracted from four safflower cultivars

Fatty acid contents at different stages ofmaturity and physicochemical characteristics of oilextracted from mature seeds of four safflowercultivars (S208, S400, S541, and S303) were studied. Results indicated that for all cultivars bothsaturated and unsaturated fatty acid contentsfluctuated with seed growth and development. Palmiticacid content decreased up to day 20 after which itstarted to increase for the S400, S541, and S303cultivars, while for S208 it progressively decreased.Stearic acid fluctuated with seed growth anddevelopment. Oleic acid showed slight changes withseed growth and development, while linoleic aciddecreased with seed growth and development for theS400, S541, and S303 cultivars while for S208 afterday 30, it started to increase significantly. For allcultivars, glyceride contents varied among thecultivars with maximum values of 97.70, 2.80 and0.20 for tri-, di- and monoglycerides, respectively. Physicochemical investigation of mature seed oilsshowed that the color, density, refractive index, free fatty acids, peroxide value, saponificationvalue and unsaponifiable matter were similar for allcultivars while viscosity, iodine value, and acetoneinsoluble matter varied among the cultivars.     

Characteristics, chemical composition and utilisation of Albizia julibrissin seed oil

The physicochemical characteristics, fatty acid and triacylglycerol compositions, DSC profile and UV/vis spectrum of oil extracted from Albizia julibrissin seeds were determined in this study. The oil content and the moisture of the seeds were 10.50% and 1.56%. The free fatty acid, the peroxide value, the p-anisidine value, the saponification value, the iodine value were 2.54%, 6.61 mequiv. O₂/kg of oil, 1.98, 190.63 (mg KOH/g) and 111.33 (g/100 g of oil), respectively. The specific extinction coefficients K₂₃₂, K₂₆₈ were 7.55 and 0.96, respectively. Linoleic acid (C_18:2, 58.58%), palmitic acid (C₁₆, 13.86%) and oleic acid (C_18:1, 10.47%) were the dominant fatty acids in the A. julibrissin seed oil. LLL (36.87%), OLL (21.62%), PLL (16.69%) and PLO + SLL (8.59%) were the abundant triacylglycerol representing > 83% of the seed oil (L: linoleic, O: oleic, P: palmitic, S: stearic). The DSC melting curves reveal that: melting point = −14.70° C and melting enthalpy = 54.34 J/g. A. julibrissin seed oil showed some absorbance in the UV-B and UV-C ranges. The results of the present analytical study show that A. julibrissin is a promising oilseed crop, which can be used for making soap, hair shampoo and UV protectors. Furthermore, the high level of unsaturated fatty acids makes it desirable in terms of nutrition.     

三角褐指藻 LPAAT基因在酵母中表达对脂肪酸的影响

从三角褐指藻（Phaeodactylum tricornutum）中克隆到1 632bp的溶血磷脂酸酰基转移酶(LPAAT)全长cDNA,其中包含的开放阅读框被命名为PtLPAAT。在毕赤酵母中异源表达PtLPAAT基因,诱导培养45h时随机选取的3个酵母转化子总脂肪酸含量分别提高了2.68%、11.14%、31.28%;诱导培养72h时同样的转化子总脂肪酸含量分别提高11.59%、18.72%、46.63%。用薄层层析法分离48h后的酵母菌体的甘油三酯,并用气相色谱法测定其脂肪酸,结果显示：与非转基因对照菌株相比,其油酸提高了0.9倍、亚油酸提高了5倍。用荧光定量PCR检测发现PtLPAAT基因的表达量随三角褐指藻油脂不断积累逐渐升高。表明在酵母中表达PtLPAAT基因不仅能够明显地提高其脂肪酸含量,而且还能选择性结合不饱和脂肪酸到甘油三酯中。     

Fatty acid composition and oxidation stability of hemp (Cannabis sativa L.) seed oil extracted by supercritical carbon dioxide

Supercritical carbon dioxide (SC-CO₂) was employed to extract oil from hemp (Cannabis sativa L.) seeds. For ground seeds, the supercritical extraction was carried out at temperatures of 40, 60 and 80 °C and pressures of 300 and 400 bar. Different solvent-ratios were applied. Supercritical CO₂ extractions were compared with a conventional technique, n-hexane in Soxhlet. The extraction yields, fatty acid composition of the oil and oxidation stability were determined. The seed samples used in this work contained 81% PUFAs, of which 59.6% was linoleic acid (ω-6), 3.4% γ-linolenic (ω-3), and 18% α-linolenic (ω-6). The highest oil yield from seeds was 22%, corresponding to 72% recovery, at 300 bar and 40 °C and at 400 bar and 80 °C. The highest oxidation stability corresponding to 2.16 mM Eq Vit E was obtained at 300 bar and 80 °C.     

Characteristics, composition and thermal stability of Acacia senegal (L.) Willd. seed oil

The chemical composition, main physicochemical properties and thermal stability of oil extracted from Acacia senegal seeds were evaluated. The oil, moisture and the ash contents of the seeds were 9.80%, 6.92% and 3.82%, respectively. Physicochemical properties of the oil were iodine value, 106.56 g/100 g of oil; saponification value, 190.23 mg KOH/g of oil; refractive index (25 °C), 1.471; unsaponifiable matter, 0.93%; acidity, 6.41% and peroxide value, 5.43 meq. O₂/kg of oil. The main fatty acids in the oil were oleic acid (43.62%) followed by linoleic acid (30.66%) and palmitic acid (11.04%). The triacylglycerols (TAGs) with equivalent carbon number ECN 44 (34.90%) were dominant, followed by TAGs ECN 46 (28.19%), TAGs ECN 42 (16.48%) and TAGs ECN 48 (11.23%). The thermal stability analysed in a normal oxidizing atmosphere showed that the oil decomposition began at 268.6 °C and ended at 618.5 °C, with two stages of decomposition at 401.5 °C and 576.3 °C. According to these results, A. senegal seed oil has physicochemical properties, fatty acids composition and thermal characteristics that may become interesting for specific applications in several segments of food and non-food industries.     

Physical,morphological and chemical characteristics,oil recovery and fatty acid composition of Balanites aegyptiaca Del. kernels

Balanites aegyptiaca Del. kernels were chemically,physically and morphologically characterized. Crude oil (49.0%) andcrude protein (32.4%) were the two major constituents of the kernels.Phytic acid content was relatively high compared to other legumes. Incontrast, antitryptic activities of the kernel flours were very low.Sapogenin contents of the full fat, defatted and testa flours were 1.5, 2.7and 3.0%, respectively. The hardness of the kernel was found to be about10.4 × 10⁵ N/m², which was somewhat high. The morphologicalstructure of the kernel using a scanning electron microscope revealedthat the protein matrix was embedded in a lake of oil droplets. Oilrecovery, as a function of pressing time, pressure, temperature and particlesize was investigated. With increasing temperature up to 70 ^°C at 400 bar, for 120 min, an oil recovery of 79.4% wasobtained. Using an expeller at 115 ^°C, about 85% of thekernel oil was recovered. The reduction of particle size had a negativeeffect on oil recovery under the same conditions. The fatty acidcomposition was not affected by the pressing temperature up to 115 ^°C. The total amount of the unsaturated fatty acids was found tobe up to 74.8% (50 ^°C) and 75.1% (115 ^°C)of the total fatty acids content.     

Method for analysis of fatty acid distribution and oil content on a single Lesquerella fendleri seed

Lesquerella fendleri is a developing oilseed crop suitable for temperate growing regions in the US. The seed oil is rich in lesquerolic acid (57%) and could serve as a domestic source of hydroxy fatty acids. A method for the analysis of fatty acids and total oil content of a half or single lesquerella seed was developed. Lesquerella seeds are small with 1000 seed weights around 0.6 g (half seed mass of 200–500 μg). Conventional analytical balances provide mass accuracy to ±40 μg which fails to provide sufficient accuracy/precession (4–40% mass error) for the initial seed mass. A microbalance which measures to ±2 μg provided good reproducibility in initial seed weights but was not suitable for mass balance of the extracted oil. A normal phase HPLC coupled to an evaporative light scattering detector gave good response for oil in the mass range of 22 μg to 110 μg/mL. Therefore, micelle concentrations from single or half seed extractions could be determined with good reproducibility. This method was then evaluated on bulk seed that had been fractionated on a gravity table. Gravity table fractionation of L. fendleri seeds obtained from a large field plot provided seven fractions with increasing bulk density. These fractions were then analyzed in sets of 30 individual seeds and as an aggregate of 50 seeds. Oil content for individual seeds varied widely (15.6–44.2%) as did lesquerolic acid content (42.2–63.7%). The mean oil content increased (27–33%) with increasing bulk density (684–745 g/L). The mean lesquerolic acid content did not correlate with bulk density.     

Variation in essential oil and fatty acid composition in different organs of cultivated and growing wild Ruta chalepensis L.

The essential oil and fatty acid composition of two provenances of Ruta chalepensis from four organs (leaves, flowers, stems and fruits) was determined. The effect of the plant part on total fatty acid contents, essential oil yields, fatty acid and volatile constituents was significant.Fatty acid profiles varied significantly among the studied provenances and organs. Linolenic acid had the highest amount in leaves of the two provenances. From R. chalepensis, in all organs, the main fatty acids were palmitic (13.10-25.31%), followed by palmitoleic (0-15.72%), stearic (1.03-6.85%), oleic (1.90-24.04%), arachidic (0.11-4.03%), eicosatetraenoic (0.10-5.60%) and behenic (0.47-6.09%) acids. Saturated fatty acids had the highest amounts in growing wild R. chalepensis flowers, and cultivated R. chalepensis stems were characterized by the predominance of polyunsaturated fatty acids. Oil composition of all studied organs has a healthy and nutritionally value. Essential oil yields varied from 0.39% to 2.46% and showed a remarkable variation with plant organs. Thirty-six volatile compounds were identified in different analyzed essential oils; 2-undecanone, 2-nonanol and 2-dodecanone had the highest percentages.