核桃油中亚油酸分离工艺研究

通过尿素包合法分离出核桃油中的亚油酸,采用高效液相色谱法测定亚油酸的含量,讨论包合时间、脂肪酸/尿素(w/w)和甲醇/尿素(v/w)对亚油酸得率和纯度的影响。结果显示,当包合温度为-5℃,包合时间为24 h,脂肪酸/尿素(w/w)为0.5,甲醇/尿素(v/w)为5,亚油酸的纯度67.17%,得率87.61%。     

嗜酸乳酸杆菌转化亚油酸为共轭亚油酸工艺条件的研究

对嗜酸乳酸杆菌转化亚油酸为共轭亚油酸的工艺条件进行了优化,其优化的工艺条件为:亚油酸与发酵液的比例为0.1%(体积比)、反应温度36℃、培养时间36 h、pH值6.0,此时共轭亚油酸的产率达37.85%.同时对共轭亚油酸异构体的组成进行了气相色谱分析.     

共轭亚油酸锌的合成工艺研究

通过利用共轭亚油酸的弱酸性质,将共轭亚油酸制成盐,以期生理功能的改变,本文利用具有生物功能活性的共轭亚油酸,先与氢氧化钠反应得到共轭亚油酸的钠盐溶液,再加入氯化锌溶液得到共轭亚油酸锌盐,平均收率为67%。为共轭亚油酸锌制成制剂的进一步研究提供了原料。     

从棉籽油制备高纯度亚油酸甲酯研究

研究由棉籽油制备高纯度亚油酸甲酯的工艺过程 ,通过尿素包结法找到一种极为有效的分离不饱和脂肪酸的方法。     

尿素包合法纯化山核桃油中的不饱和脂肪酸

将山核桃油经皂化后酸化制得脂肪酸,再对脂肪酸进行尿素包合,使其中饱和脂肪酸与不饱和脂肪酸分离,从而提高不饱和脂肪酸的含量。实验中对皂化反应条件及尿素包合条件进行了优化。结果表明：在1mol/L氢氧化钾-无水乙醇溶液中反应5h,山核桃油能够皂化完全;在脂肪酸：尿素：无水乙醇比为1：2：10,温度为-18℃,时间为20h的条件下进行尿素包合,效果最佳,不饱和脂肪酸的含量由78.3％增加到94.2％。     

紫草油中亚麻酸的分离与提纯方法的研究

以中国东北地区产的紫草种籽为原料 ,气相色谱内标法进行跟踪定量分析 ,采用改进的尿素包合法 ,对从紫草种籽油中分离提纯亚麻酸的诸工艺条件进行了实验研究。实验结果表明 :每 2 0g紫草油最终可得不饱和脂肪酸甲酯 10 2g ,其中w(亚麻酸甲酯 ) =83 1%。最佳工艺条件为 :(1)水解反应 :m(KOH)∶m (CH3 CH2 OH)∶m(H2 O) =2∶15∶5 ,氮气保护 ,反应温度为 6 0℃ ,酸化时pH =3～ 4 ;(2 )甲酯化反应 :V(混合脂肪酸 )∶V(甲醇 )∶V(浓硫酸 ) =92∶4 0 0∶3;(3)尿素包合 :m(混合脂肪酸甲酯 )∶m(尿素 ) =1∶2 ,包合温度为 - 6℃ ,时间 8h。     

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%。     

尿素包合法分离火麻仁油不饱和脂肪酸的研究

研究了尿素包合法提取火麻仁油中不饱和脂肪酸的工艺条件。分析了温度、时间、尿素用量、溶剂用量对相对含量和收率的影响。结果表明:采用95%乙醇作为溶剂,尿素与火麻仁粗油的质量比为0.38∶1,包合温度-10℃,包合时间24 h,乙醇与尿素的体积质量比为7∶1,为较优条件。在此条件下,非饱和脂肪酸相对含量为98.6%,收率为70.5%。     

共轭亚油酸盐的研究进展

本文通过共轭亚油酸的结构、生理功能,引出了共轭亚油酸盐的应用。并分别从共轭亚油酸的钙盐、锌盐、镁盐、钠盐和钾盐的应用出发综述了近年来有关共轭亚油酸盐的研究进展,阐述了其广泛的开发应用前景。     

碱法异构化亚油酸甲酯制备共轭亚油酸

该文探索在乙二醇溶剂中以氢氧化钠碱法异构化亚油酸甲酯制备共轭亚油酸的方法,适宜的异构化条件为m(氢氧化钠)∶m(亚油酸甲酯)∶m(乙二醇)=1∶5∶8.4,170℃反应4 h,亚油酸甲酯转化率和共轭亚油酸产率分别为92.4%和89.3%。该法比目前常用的亚油酸原料法的优越之处体现在:以氢氧化钠取代常用碱氢氧化钾,降低成本;以亚油酸甲酯取代亚油酸为原料,避免了原料本身大量消耗碱;反应初期避免原料大量皂化,减小了体系的传质阻力,因而减少了溶剂乙二醇消耗量。     

Cost of producing linoleic acid from safflower oil

Linoleic acid of 97% purity can be made from safflower oil by liquid-liquid extraction at a “cost to make” of about 21 cents a 1b. Calculations for the cost estimate were based on pilot-plant investigations. Fixed capital investment for a plant with an annual capacity of 20 million 1b has been estimated at approximately $1,800,000. Such a plant could be converted readily to the production of a variety of other fatty acids. A laboratory of the No. Utiliz. Res. & Dev. Div. ARS, U.S.D.A.     

Preparation of conjugated linoleic acid from safflower oil

Synthetically prepared mixtures of conjugated linoleic acid (CLA) are widely used in animal and cell culture studies to investigate the potential effects of the Δ9c, 11t-18:2 isomer found in food products from ruminant animals. Alkali isomerization of linoleic acid is a common method used in the synthesis of a mixture of CLA isomers containing predominantly the Δ9c, 11t-18:2 and Δ10t, 12c-18:2 isomers. Some biological activity might also be mediated by the Δ10t, 12c-18:2 isomer. Currently few published methodologies exist describing procedures for the enrichment of these two isomers. A method is described herein to take advantage of an inexpensive oil, safflower oil, for use in synthesis of CLA and a procedure to enrich the Δ10t, 12c-18:2 isomer.     

Photochemical production of conjugated linoleic acid from soybean oil

Conjugated linoleic acid (CLA), an anticarcinogenic compound with numerous other health benefits, is present mainly in dairy and beef lipids. The main CLA isomer present in dairy and beef lipids is cis 9, trans 11 CLA at a 0.5% concentration. The typical minimum human dietary intake of CLA is 10 times less than the 3 g/d suggested requirement that has been extrapolated from animal and cell-line studies. The objectives of this study were to produce CLA isomers from soybean oil by photoisomerization of soybean oil linoleic acid and to study the oxidation status of the oil. Refined, bleached, and deodorized soybean oil with added iodine concentrations of 0, 0.1, 0.25, and 0.5% was exposed to a 100-W mercury lamp for 0 to 120 h. An SP-2560 fused-silica capillary GC column with FID was used to analyze the esterified CLA isomers in the photoisomerized oil. The CLA content of the individual isomers was optimized by response surface methodology. Attenuated total reflectance (ATR)-FTIR spectra in the 3400 to 3600 cm⁻¹ range and ¹H NMR spectra in the 8 to 12 ppm range of the photoisomerized soybean oil were obtained to follow hydroperoxide formation. The largest amount of cis 9, trans 11 CLA isomer in soybean oil was 0.6%, obtained with 0.25% iodine and 84 h of photoisomerization. Lipid hydroperoxide peaks in the ATR-FTIR spectra and aldehyde peaks in the ¹H NMR spectra were not observed in the photoisomerized soybean oil, and the spectra were similar to that of fresh soybean oil. This study shows that CLA isomers can be produced simply and inexpensively from soybean oil by photoisomerization.     

从脂肪酸中提取精制亚油酸的研究

本文介绍了从脂肪酸中提取精制亚油酸的方法，并讨论了结晶温度和结晶时间对产品质量的影响，得出了最佳工艺条件，最终制成的精制亚油酸收率可达65％左右；溶剂回收率可达80％～85％。     

Concentration of linoleic acid from cottonseed oil by starch complexation

The extraction of linoleic acid from fatty acids(FA) of the cottonseed oil using starch–FA complexes was developed for the first time. We showed that starch can form inclusion complexes of different strengths with FA and that the different strengths stem from the differences in chain length, degree of unsaturation, and position of double bonds of FA. The optimal separation conditions were determined as follows: The inclusion temperature is 69 °C, the inclusion time is 30 min, the starch/FA mass ratio is 10:1, and the ratio of the volume of methanol–water solution and the mass of FA is 18:1. Compared to urea inclusion complexation, starch complexation has milder reaction temperature and shorter reaction time. Under these conditions, linoleic acid can be concentrated from 38.9% to 70.04% by one-off extraction. Moreover, the experimental results demonstrate the almost perfect reusability of starch. These results show that starch complexation is a promising method that can be used to obtain highly concentrated linoleic acid from cottonseed oil.     

月苋草油制备共轭亚油酸的研究

GC—MS分析月苋草油中脂肪酸的组成,其亚油酸含量很高。探讨制备和富集提纯亚油酸反应条件,研究在高压条件下金属催化剂对亚油酸共轭化的影响。     

Conjugated linoleic acid production from linoleic acid by lactic acid bacteria

After screening 14 genera of lactic acid bacteria, Lactobacillus plantarum AKU 1009a was selected as a potential strain for CLA production from linoleic acid. Washed cells of L. plantarum with high levels of CLA production were obtained by cultivation in a nutrient medium with 0.06% (wt/vol) linoleic acid (cis-9,cis-12-octadecadienoic acid). Under the optimal reaction conditions with the free form of linoleic acid as the substrate, washed cells of L. plantarum produced 40 mg CLA/mL reaction mixture (33% molar yield) from 12% (wt/vol) linoleic acid in 108 h. The resulting CLA was a mixture of two CLA isomers, cis-9,trans-11 (or trans-9,cis-11)-octadecadienoic acid (CLA1, 38% of total CLA) and trans-9,trans-11-octadecadienoic acid (CLA2, 62% of total CLA), and accounted for 50% of the total FA obtained. A higher yield (80% molar yield to linoleic acid) was attained with 2.6% (wt/vol) linoleic acid as the substrate in 96 h, resulting in CLA production of 20 mg/mL reaction mixture [consisting of CLA1 (2%) and CLA2 (98%)] and accounting for 80% of total FA obtained. Most of the CLA produced was associated with the cells (ca. 380 mg CLA/g dry cells), mainly as FFA.     

Buttonweed seed oil a source of linoleic acid

Summary Buttonweed seeds (Abutilon theophrasti) contain 15 to 17% oil. The oil contains about 58% linoleic acid which may be concentrated by simple fractionation into fractions containing as high as 83% of the acid. This suggests the possible use of the oil as a source of linoleic acid. The seed also has an appreciable sterol content.     

Isolation of a natural isomer of linoleic acid from a seed oil1,2

trans-10-trans-12-Octadecadienoic acid was found to be a component of the glyceride oil of the seeds ofChilopsis linearis (Cav.) Sweet. It was isolated by fractional crystallization of the acids at low temperatures. Identification was made by absorption spectra, by the adduct with maleci anhydride, and by identification of degralative products. The conjugated triene of the oil was also isolated and identified astrans-9-trans-11-cis-13octadecatrienoic acid. in two samples of seed, the diene acid constituted about 9% of the oil and the triene acid 18% and 25%. Presented at the AOCS meeting in Toronto, Canada, 1962. Issued as NRC No. 7592.