混合脂肪酸乳化分离原理

分解动植物油脂得到的混台脂肪酸含有饱和脂肪酸和不饱和脂肪酸。用乳化分离的方法把混合脂肪酸分离成为饱和程度     

尿素包合法分离橡胶籽油中的多价不饱和脂肪酸

用尿素包合法从橡胶籽油混合脂肪酸中分离多价不饱和脂肪酸 ,用正交设计实验法对分离工艺进行研究 ,其最佳分离条件是 :原料配比为m(混合脂肪酸 )∶m(尿素 )∶m(乙醇 ) =1 0 0∶1 5∶1 8,回流时间 12 0min。经一次尿素包合法分离即可得到多价不饱和脂肪酸质量分数大于90 %的产品 ,实验收率大于 35 %     

GC-MS法分析红树林内生真菌Nigrospora sp.的脂肪酸成分

文章采用(硫酸)=2%的甲醇溶液酯化法对红树林内生真菌Nigrospora sp.代谢产物的石油醚部位衍生化,以气相色谱-质谱联用仪分离和鉴定脂肪酸的组成和含量。结果表明:共分离鉴定出24种脂肪酸,占脂肪酸总量的91.32%,其中不饱和脂肪酸占脂肪酸总量的49.97%,饱和脂肪酸占脂肪酸总量的41.35%。     

干法冷冻在妥尔油脂肪酸提纯中的应用

以妥尔油脂肪酸为原料,经过低温梯度冷冻结晶将硬脂酸和不饱和脂肪酸进行分离,再经高速离心分离,得到纯度较高的油酸、亚油酸等不饱和脂肪酸。该法可实现规模生产和连续操作,产品收率可达90%～95%。     

由直链不饱和脂肪酸异构制备支链脂肪酸的研究进展

介绍了直链不饱和脂肪酸制备支链脂肪酸的研究现状,综述了脂肪酸异构机理,异构催化剂如白土催化剂、沸石催化剂,催化剂的筛选原则,着重讨论了各种常用沸石对于脂肪酸异构反应不同的影响以及现有的合成工艺。分析了脂肪酸的分离技术,包括精馏分离法、溶剂结晶法、尿素包结法、超临界流体萃取法的优缺点,指出沸石催化生产支链饱和脂肪酸的关键问题是需要解决混合脂肪酸作为原料反应的选择性问题,其相关的基础性工作,如更明确的反应机理和催化剂结构参数对反应的影响,仍是将来的研究方向。     

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％。     

C16、C18混合脂肪酸分离技术研究进展

C16、C18混合脂肪酸中含有很多经济价值很高的组分,若能将这些组分分离出来加以利用,将极大地提高混合脂肪酸的利用价值,因此研究C16、C18混合脂肪酸的分离技术具有非常重要的意义。本文介绍了减压精馏、低温结晶、尿素包合、银离子络合、生物酶催化法等C16、C18混合脂肪酸分离方法在近十年来的研究进展,并分析了各种分离方法的优缺点和适用范围。减压精馏可以有效地将混合脂肪酸分离成C16组分与C18组分,但该法的主要问题是加热易使不饱和组分变质。尿素包合法最常用来分离C16、C18混合脂肪酸中的饱和组分与不饱和组分,目前对该法的研究主要集中在工艺条件的优化与改善。生物酶催化法选择性高、反应条件温和、绿色环保,目前已被用来分离α-亚麻酸以及γ-亚麻酸且效果良好。最后展望了C16、C18混合脂肪酸分离技术的发展前景,指出两种或多种分离方法组合以及生物酶催化法将是未来的发展趋势。     

不饱和脂肪酸β-环糊精包合物的工业化制备研究

采用β-环糊精包合法从花椒油中提取α-亚麻酸,使之其中的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。通过中试考察实施了不饱和脂肪酸工业化提取的工艺设计及工艺条件,以提高α-亚麻酸的提取率。工业生产之最佳包合条件:95%乙醇∶FFΑ∶β-CD=1∶2∶16,包合温度为60℃,包合时间为1.5 h。通过气相色谱-质谱联用仪(GC-MS)对包合后的脂肪酸成分进行了分析,共检测出3种脂肪酸,使α-亚麻酸的相对含量得以明显提高。     

从脂肪酸的尿素包合法固相物中回收尿素的工艺

比较5种回收尿素包合法固相物中的脂肪酸和尿素的方法,其中,甲醇和甲苯的混合溶剂法的回收效果最好。当尿包固相物∶甲醇∶甲苯(g∶mL∶mL)用量比为1∶3∶3时,脂肪酸和尿素的回收率分别为99.12%、99.46%。对回收脂肪酸进行FT-IR、GPC和GC-MS分析:回收的脂肪酸中含有饱和脂肪酸和不饱和脂肪酸(Unsaturated Fatty Acids,UFAs)结构;回收脂肪酸相对分子质量为443,含量93.92%;UFAs含量为93.96%。回收尿素的EMS微观结构分析:回收尿素为针状透明晶体结构和良好的结晶度。考察了回收尿素多次分离多不饱和脂肪酸的效果,重复回收和利用的结果显示:回收尿素6次分离得到的产品中PUFAs含量在81%～89%、UFAs含量为100%、收率在60%～72%。     

气质联用技术分析大兴安岭野生玫瑰花的脂肪酸组成

目的采用气质联用技术分析生长于黑龙江北部地区大兴安岭野生玫瑰花脂肪酸的组成。方法将同一天采摘并储存于相同条件下的野生玫瑰花,采用索氏提取法,以石油醚为溶剂对野生玫瑰花的不同部位萃取得到玫瑰花脂肪酸,经三氟化硼-甲醇酯化后,用气质联用技术进行定性和定量分析。结果野生玫瑰花不同部位(花瓣、花蕊、花托及花萼)的脂肪酸组成不同,花瓣中共检测出14种脂肪酸,其中不饱和脂肪酸相对含量为63.78%;花蕊中共检测出15种脂肪酸,其中不饱和脂肪酸的相对含量为59.1%;花托中共检测出13种脂肪酸,其中不饱和脂肪酸的相对含量为47.02%;花萼中共检测出20种脂肪酸,其中不饱和脂肪酸的相对含量为40.3%。结论野生玫瑰花不同部位(花瓣、花蕊、花托及花萼)的脂肪酸组成不同,花瓣部位富含不饱和脂肪酸,对提升玫瑰花精油的质量,充分利用野生玫瑰花资源提供了参考。     

中华猕猴桃种子提取不饱和脂肪酸的研究

用中华猕猴桃种子提取不饱和脂肪酸 ,宜用石油醚作萃取剂 ,经过萃取、脱蜡、浓缩、精制后 ,其得率约为种子质量的 2 8% ,经分析 ,其亚麻酸与亚油酸含量占总脂肪酸含量的 89.4 %。     

单体酸混合物成分的GC-MS分析

研究了生产二聚酸时得到的副产品单体酸的化学组成的GC MS分析方法,样品首先用质量浓度为140g/L KOH M eOH进行甲酯化,然后用GC MS进行分析和鉴定,共鉴定出棕榈酸、肉豆蔻酸、10甲基月桂酸、12甲基十四烷酸、十八烯酸等13种物质,总脂肪酸的质量分数占76.71%,其中饱和酸占66.36%,不饱和酸占10.35%,其中直链酸占饱和脂肪酸的41.02%,支链酸即异构酸占饱和脂肪酸的58.98%。     

Solvent-Assisted Crystallization of Fatty Acid Alkyl Esters from Animal Fat

An easy and efficient method for the separation of saturated and unsaturated fatty acid mono alkyl esters, prepared from animal fat, was developed. The most efficient separation was achieved by the use of solvents such as methanol and acetone at low temperatures. The dilution of the alkyl esters with 10 times the amount of solvent (10:1 v/w) and storage of the mixture for 4 h at ?22 °C could be defined as optimum conditions. After filtration of the saturated fraction at the corresponding temperature very pure fractions were obtained. For fatty acid methyl esters deriving from tallow, with an initial content of saturated fatty acids of almost 50 %, a saturated ester fraction with only 5 % unsaturated fatty acids and an unsaturated ester fraction with about 9 % of saturated fatty acids could be obtained. The solvent easily could be recovered by distillation. In addition fatty acid ethyl, 1‐propyl, 2‐propyl, 1‐butyl, tert‐butyl and 3‐methyl‐1‐butyl esters were prepared and separated into saturated and unsaturated fractions. All fractions were analyzed according to the fatty acid compositions and showed similar or slightly worse results compared to the methyl esters. The cold filter plugging points of the unsaturated fractions were measured, showing the lowest value for the unsaturated methyl ester fraction at ?26 °C. The fractionation with the use of solvents is an easy tool in order to obtain fatty acid alkyl esters with excellent cold temperature behavior out of animal fat.     

Synthesis of Chloroalkoxy eicosanoic and docosanoic acids from meadowfoam fatty acids by oxidation with aqueous sodium hypochlorite

Chloroalkoxy substituted C₂₀ and C₂₂ fatty acids can be synthesized from the unsaturated fatty acids in meadow-foam oil by reaction of the fatty acids with primary or secondary alcohols and an aqueous sodium hypochlorite solution (commercial bleach). The reactions are conducted at room temperature for 3 h. Chlorohydroxy fatty acid derivatives are formed as by-products owing to the presence of water in the reaction mixture. Chlorinated δ-lactones are also produced by direct reaction of sodium hypochlorite with the Δ5 unsaturated fatty acids present in meadowfoam or by ring closure of the 6-chloro-5-hydroxy fatty acids. The product yield of chloroalkoxy fatty acids is dependent on the nature and volume of the alcohol used in the reaction, as well as the concentration and pH of the sodium hypochlorite solution. Primary alcohols such as methanol and butanol produce maximal yields (50–60%) of chloroalkoxy fatty acids whereas the secondary alcohol 2-propanol gives a 30% yield. Chloroalkoxy fatty acid yields can be increased to 75–80% by elimination of water from the reaction mixture through a procedure that partitions sodium hypochlorite from water into hexane/ethyl acetate mixtures. All of the reaction products were fully characterized using nuclear magnetic resonance and gas chromatography-mass spectrometry.     

海南油棕果肉中脂肪酸的成分分析

用乙醚萃取海南油棕果肉中的油脂,油脂中的脂肪酸采用氢氧化钾-甲醇溶液进行甲酯化后,利用气相色谱-质谱联用技术（GC—MS）对其中的脂肪酸成分进行分析。结果分离鉴定出4种脂肪酸成分,它们分别是棕榈酸（45．62％）、油酸（37．70％）、亚油酸（8．39％）、硬脂酸（8．29％）。其中不饱和脂肪酸高达46％以上,有进一步开发利用的潜力。     

不同性质的脂肪酸对脂肪变性L02肝细胞凋亡和葡萄糖调节蛋白78表达的影响

目的探讨不同性质脂肪酸对脂肪变性L02肝细胞凋亡和葡萄糖调节蛋白78(GRP78)表达的影响。方法用油酸(不饱和脂肪酸)和软脂酸(饱和脂肪酸)分别诱导建立L02细胞脂肪变性模型;油红O染色观察细胞内脂滴的变化;甘油三酯(TG)试剂盒检测细胞内TG含量;流式细胞术Annexin-V/PI双染检测细胞凋亡率;AO/EB染色法观察细胞凋亡形态;Westernblot和RT-PCR法分别检测GRP78蛋白和mRNA的表达。结果不同性质的脂肪酸均可导致L02细胞发生以甘油三酯升高为特点的脂肪变性。流式细胞术及AO/EB染色形态观察显示,两种类型的脂肪酸均可引起不同程度的肝细胞凋亡,软脂酸组在48和72h的细胞凋亡率显著高于对照组、DMSO组以及油酸组,同时伴有GRP78蛋白及mRNA表达的明显增加。结论油酸不能影响GRP78的表达,饱和脂肪酸可能通过上调葡萄糖调节蛋白78的表达诱导脂肪变性肝细胞的凋亡。     

番荔枝籽油脂脂肪酸组成的GC-MS分析

研究了番荔枝籽油脂中脂肪酸的组成.用索氏脂肪抽提器提取番荔枝籽的油脂,并以GC-MS分析油脂脂肪酸的组成.结果表明,番荔枝籽油脂收率达29.2％;番荔枝籽油脂中含有8种脂肪酸,主要为:油酸(45.37％)、亚油酸(30.68％)、棕榈酸(13.60％)和硬脂酸(8.94％),其中不饱和脂肪酸含量达76.29％.番荔枝籽含油量高,脂肪酸种类丰富,尤其是不饱和脂肪酸含量较高,具有较高的开发利用价值.     

番荔枝籽油脂脂肪酸组成的GC—MS分析

研究了番荔枝籽油脂中脂肪酸的组成。用索氏脂肪抽提器提取番荔枝籽的油脂,并以GC-MS分析油脂脂肪酸的组成。结果表明,番荔枝籽油脂收率达29．2％;番荔枝籽油脂中含有8种脂肪酸,主要为：油酸（45．37％）、亚油酸（30．68％）、棕榈酸（13．60％）和硬脂酸（8．94％）,其中不饱和脂肪酸含量达76．29％。番荔枝籽含油量高,脂肪酸种类丰富,尤其是不饱和脂肪酸含量较高,具有较高的开发利用价值。．     

Fatty acid selectivity of lipases: Erucic acid from rapeseed oil

The fatty acid selectivity of several commercial lipases was evaluated in the hydrolysis of high-erucic acid rapeseed oil (HEARO). The lipase ofPseudomonas cepacia catalyzed virtually complete hydrolysis of the oil (94–97%), while that ofGeotrichum candidum discriminated strongly against erucic acid, especially in esterification. A two-step process is suggested for obtaining a highly enriched erucic acid in which theG. candidum lipase is employed to selectively esterify the fatty acid residues of unsaturated C-18, and shorter chain acids, from a mixture of HEARO fatty acids obtained from total hydrolysis of the oil withP. cepacia lipase.     

Microbial Conversion of Vegetable Oil to Rare Unsaturated Fatty Acids and Fatty Alcohols by an <Emphasis Type="Italic">Aeromonas hydrophila</Emphasis> Isolate

We isolated two new microorganisms capable of converting vegetable oil to several rare unsaturated fatty acids and rare unsaturated fatty alcohols from a soil sample. The strains were identified as belonging to the same genus and species, Aeromonas hydrophila. The rare unsaturated fatty acids and rare unsaturated fatty alcohols were accumulated as a wax ester form by the strains. Compared to other strains, the A. hydrophila isolates effectively decreased fatty acid chain lengths and converted rapeseed oil, which is rich in 9-C18:1 fatty acid, into rare fatty acids, such as 7-C16:1 fatty acid and 5-C14:1 fatty acid. Furthermore, the A. hydrophila isolates converted the resulting fatty acids to rare unsaturated fatty alcohols, such as 7-C16:1 fatty alcohol and 5-C14:1 fatty alcohol. The isolates also converted safflower oil, which is rich in 9,12-C18:2 fatty acid, to 7,10-C16:2 fatty acid, 5,8-C14:2 fatty acid, 9,12-C18:2 fatty alcohol, 7,10-C16:2 fatty alcohol, and 5,8-C14:2 fatty alcohol. 7,10,13-C16:3 fatty acid, 9,12,15-C18:3 fatty alcohol, and 7,10,13-C16:3 fatty alcohol were also converted from linseed oil, which is rich in 9,12,15-C18:3 fatty acid, by the A. hydrophila isolates. These fatty acids and fatty alcohols are rarely found in natural oils. Since decreasing fatty acid carbon chain lengths from the carboxyl end and reducing unsaturated fatty acids to unsaturated fatty alcohols are both difficult reactions to accomplish by chemical means, we suggest that these A. hydrophila isolates may facilitate introduction of new bioprocess for producing rare unsaturated fatty acids and rare unsaturated fatty alcohols, especially fatty alcohols harboring more than two double bonds.