牡蛎中脂肪酸在储藏过程中的稳定性

用超临界流体萃取 (SFE)及GC MS分析了新冷冻干燥及保存 1 5d ,30d ,45d ,60d ,75d ,90d后的鲜牡蛎粉中的 2 3种脂肪酸组分的质量分数。发现在存放过程中牡蛎脂肪酸的稳定性与其不饱和度有关 ;不饱和度越高 ,脂肪酸越易被氧化 ,其中多不饱和脂肪酸的氧化是逐渐进行的 ,没有特定的稳定期。放置 90d后 ,牡蛎脂肪酸中脑黄金EPA的质量分数由原来的 1 6 94%降至 5 43% ,DHA由 9 2 5%降至 2 86%。     

马齿苋及其籽中脂肪酸的比较研究

本实验利用ＧＣ－ＭＳ分析技术对马齿苋全草及其籽中的脂肪酸（以甲酯的形式）进行了分析，共鉴定出８种脂肪酸。全草中以亚麻酸（４７．１６％）、亚油酸（２２．００％）及棕榈酸（１７．４％）为主，籽中以亚油酸（４５．８６％）及亚麻酸（３０．６１％）为主。     

油菜蜂花粉中脂肪酸的GC-MS分析

以石油醚和乙醚为溶剂，采用索氏抽提法提取油菜蜂花粉中的粗脂肪，进行甲酯化处理，并用GC－MS技术对脂肪酸甲酯进行分离鉴定，共鉴定出10种脂肪酸；测定其相对含量，其中不饱和脂肪酸相对含量高达76.0%，多不饱和脂肪酸相对含量为53.2%。     

微波辅助衍生化GC-MS法测定食用油中的脂肪酸

利用微波技术,研究了用ＫＯＨ－甲醇,Ｈ２ＳＯ４－甲醇－甲苯、ＨＣｌ－甲醇等不同体系对食用油中的脂肪酸进行了衍生化,系统地比较了它们的优劣势,以及适合的分析对象,在１ｍｉｎ内完成衍生物生化反应,选用正庚烷代替传统方法的苯＋石油醚作为脂肪酸甲酯蝗提取剂,与传统消解及衍生化方法相比,具有节省溶剂,省时,易于操作等特点。     

GC-MS法分析植物油酸中的脂肪酸

植物油酸是以植物油的副产物 (皂角油 )为原料 ,经水解、精馏等工艺制成 ,常用作油漆、涂料的原料 ,也用以生产矿山浮选剂、乳化炸药、乳化农药、酰胺产品等 ,其中脂肪酸的组成日益引起人们重视 ,但未见植物油酸中脂肪酸组成的研究。本文用硫酸 -甲醇溶液作甲酯化试剂 ,以毛细管色谱 -质谱联用仪定性 ,气相色谱法定量 ,对植物油酸中的脂肪酸组成进行了分析 ,获得满意结果     

红橘油中脂肪酸组成的 GC-MS分析

用正己烷溶解达川和万县产的两种红橘油,将样品皂化和甲酯化后,以毛细管柱DB－WAX作为分离柱,用气相色谱－质谱法测定其中的脂肪酸组成,两种红橘油的主要脂肪酸成分有明显的差别,两者的不饱和脂肪酸相对含量分别为92．1％及76．7％。     

烤鳗油的脂肪酸组成及其利用价值

用ＧＣ－ＭＳ法测定了烤鳗油脱腥前后的脂肪酸组成,并对其利用价值进行了评价。实验结果表明,经高温减压水蒸汽蒸馏脱腥处理后,烤鳗油中不饱和脂肪酸含量占其脂肪酸总量的７０％,二十碳五烯酸（ＥＰＡ）和二十二碳六烯酸（ＤＨＡ０含量分别达４．０１％和７．７３％。利用烤鳗油的结构特点,有可能开发出一系列特殊的保健品。     

GC/MS法快速测定食用植物油中脂肪酸含量

脂肪酸以甘油三酯的形式存在于植物油中,我们先用KOH-甲醇方法将它转化为甲酯,用正交设计法探索出最佳的酯交换条件,整个过程5分钟可完成。然后用GC/MS/MSD进行定性定量分析。测定了8种食用植物油中六种脂肪酸的含量。     

兔骨骼肌肌质网磷脂组分及脂肪酸的分析

 分析了兔骨骼肌肌质网磷脂的组成及摩尔分数,并用气相色谱法对两种主要磷脂的脂肪酸组成及摩尔分数进行了测定。     

Biosynthesis of iso-fatty acids in myxobacteria: iso-even fatty acids are derived by alpha-oxidation from iso-odd fatty acids

The biosynthesis of iso-fatty acids was investigated in the myxobacteria Myxococcus xanthus and Stigmatella aurantiaca by feeding labeled precursors of these fatty acids and by conducting detailed analysis of the fatty acid profiles and fatty acid MS and NMR spectra. These experiments revealed that in S. aurantiaca all iso-even fatty acids are formed via alpha-oxidation of iso-odd fatty acids and not by using valine-derived isobutyryl-CoA.     

Exotic biomodification of fatty acids

Many biotransformations of mid- to long chain fatty acyl derivatives are intrinsically interesting because of their high selectivity and novel mechanisms. These include one carbon transfer, hydration, isomerization, hydrogenation, ladderane and hydrocarbon formation, thiolation and various oxidative transformations such as epoxidation, hydroxylation and desaturation. In addition, hydroperoxidation of polyunsaturated fatty acids leads to a diverse array of bioactive compounds. The bioorganic aspects of selected reactions will be highlighted in this review; 210 references are cited.     

Synthesis of benzophenone-containing fatty acids

Syntheses of new benzophenone-containing fatty acids (FABPs) 1, 5, and 6 and a new route to FABP 3 are described. Combined with the known 2 and 4, these FABPs comprise a set of photoactivatable fatty acid analogues with the crosslinking site at defined distances from the carboxylic acid hydroxyl group oxygen atoms ranging from 7.9 to 25.0 A.     

Dicarboxylic acids and hydroxy fatty acids in different species of fungi

Secondary metabolites of fungi can be responsible for allergies; therefore, the identification of compounds produced by these organisms is very important. Fungi produce large amounts of secondary metabolites, which belong to groups of chemicals such as: dicarboxylic acids, hydroxy acids, alcohols, hydrocarbons, esters, fatty acids, sterols, amino acids and mycotoxins. The presence of all these compounds in human proximity contributes to many diseases. Therefore, the aim of the study was a qualitative and quantitative analysis of hydroxy and dicarboxylic acids produced by fungi occurring in student hostel in Poland, in the province of Pomerania. The following species of fungi were subjected to extraction: Aspergillus niger, Aspergillus fumigatus, Aspergillus candidus, Rhizopus sp., Geotrichum candidum, and Penicillium chrysogenum. A mixture of ethyl acetate and methanol was used for the extraction. The obtained extracts were further analyzed by gas chromatography mass spectrometry (GC–MS). In all samples of fungi, the presence of a total of 22 acids, including 13 dicarboxylic and 9 hydroxy acids, was confirmed. Most acids (17 different acids) were identified in A. fumigatus. Only 10 acids were identified in the mycelium of G. candidum and A. niger. Acids which were identified in all samples of the mycelium were 22-hydroxydocosanoic acid, 24-hydroxytetracosanoic acid and adipic acid. The most abundant compounds were 22-hydroxydocosanoic acid in A. fumigatus, A. candidus, Rhizopus sp., G. candidum and P. chrysogenum, and succinic acid in A. niger. More experiments are needed to understand the physiological role of hydroxy and dicarboxylic acids. We hope that our results are an important contribution to further studies on the human health.     

Paper chromatography of fatty acids and halogenated organic acids

A paper chromatographic method is described for the identification of the volatile fatty acids and some of their bromo- and iodo-derivatives. Some new spraying reagents are suggested which enable the different classes of acids to be detected in presence of one another.     

Gas chromatographic analysis of infant formulas for total fatty acids, including trans fatty acids

Twelve powdered and 13 liquid infant formulas were analyzed by using an extension of AOAC Official Method 996.01 for fat analysis in cereal products. Samples were hydrolyzed with 8 N HCl and extracted with ethyl and petroleum ethers. Fatty acid methyl esters were prepared by refluxing the mixed ether extracts with methanolic sodium hydroxide in the presence of 14% boron trifluoride in methanol. The extracts were analyzed by gas chromatography. In powdered formulas, saturated fatty acid (SFA) content (mean +/- SD; n = 12) was 41.05 +/- 3.94%, monounsaturated fatty acid (MUFA) content was 36.97 +/- 3.38%, polyunsaturated fatty acid (PUFA) content was 20.07 +/- 3.08%, and total trans fatty acid content was 1.30 +/- 1.27%. In liquid formulas, SFA content (mean +/- SD; n = 13) was 42.29 +/- 2.98%, MUFA content was 36.05 +/- 2.47%, PUFA content was 20.65 +/- 2.40%, and total trans fatty acid content was 0.88 +/- 0.54%. Total fat content in powdered formulas ranged from 4.4 to 5.5 g/100 kcal and linoleic acid content ranged from 868 to 1166 mg/100 kcal. In liquid formulas, total fat content ranged from 4.1 to 5.1 g/100 kcal and linoleic acid content ranged from 820 to 1100 mg/100 kcal. There were no significant differences between powdered and liquid infant formulas in concentrations of total fat, SFA, MUFA, PUFA, or trans fatty acids.     

杉木针叶磷脂酰甘油脂肪酸组成分析

 用改进的DEAE阴离子交换柱色谱法和硅胶薄层色谱法分离制备杉木针叶磷脂酸甘油，用气相色谱法测定了它的脂肪酸组成。分析结果表明，抗寒性强的杉木品种的针叶磷脂酰甘油脂肪酸的（18:1＋18:2＋18:3）／[16:0＋16:1（3t）]比值比不抗寒品种的高。     

Stability of reduced molybdosilicic acids

The effect of reduction on the stability of molybdosilicic acids (MSA) has been investigated. It has been found that when two or more of the 12 Mo(VI) atoms in alpha or beta-MSA are reduced to Mo(V), the products are stable in alkaline medium. Also, beta-MSA reduced to this extent is stable at higher temperature and is not transformed into alpha-MSA. Solutions in which the apparent degree of reduction is less than 2 Mo(V) per MSA ion should be treated as a mixture of unreduced MSA and MSA reduced exactly to 2 Mo(V) per MSA ion. A mixture of unreduced MSA and MSA reduced to contain 4 Mo(V) per MSA ion is not a stable system. The yellow unreduced MSA is reduced by the reduced form to give the product with 2 Mo(V) per MSA ion. The consequences for determining silicon as MSA are given, as well as a method of obtaining pure beta-MSA from a mixture of alpha-MSA and beta-MSA.