Cyclopropenoid fatty acids of six seed oils from malvaceae

The seeds ofAlyogine hakeifolia, Alyogine huegelii,Gossypium australe, Hibiscus coatesii, Lawrencia viridigrisea andRadyera farragei (Malvaceae) contained 13.5-18.6% oil. Linoleic acid predominated (60.0-68.2%) in the component fatty acids of all the oils, followed by palmitic (9.9-18.1%) and oleic acids (7.8-15.8%). Cyclopropene fatty acids, malvalic and sterculic, were present in small concentrations (1.0-4.4%, 0.1-1.5% respectively). Dihydrosterculic acid was present in small quantities (trace-2.1%). *To whom correspondence should be addressed at Department of Chemistry, P.O. Box 320, University of Papua New Guinea, Papua, New Guinea.     

Validation of Two Methods for Fatty Acids Analysis in Eggs

A comparative study between two methods (lipid extraction followed by saponification and methylation, and direct methylation) to determine the fatty acids in egg yolk was evaluated. Direct methylation of the samples resulted in lower fatty acid content and greater variation in the results than the lipid extraction followed by saponification and methylation. The low repeatability observed for the direct HCl methylation method was probably due to a less efficient extraction and conversion of the fatty acids into their methyl esters as compared to the same procedure starting with the lipid extract. As the lipid extraction followed by esterification method was shown to be more precise it was validated using powdered egg certified as reference material (RM 8415, NIST) and applied to samples of egg, egg enriched with polyunsaturated omega-3 fatty acids (n-3 PUFA), and commercial spray-dried whole egg powder.     

气相色谱-质谱法分析山楂中的脂肪酸

为了促进山楂及山楂核在药物、精细化工领域的应用,用气相色谱-质谱联用仪,改良脂肪酸甲酯化法检测出山楂果肉中的7种脂肪酸,分别为棕榈酸、亚油酸、油酸、亚麻酸、硬脂酸、花生酸及山嵛酸。用CSASS软件进行峰识别及确定峰面积,峰面积归一化法计算每种脂肪酸的相对质量分数。分析测定了河北、安徽、山东、吉林、辽宁5个产地山楂药材中的脂肪酸相对质量分数,各产地去核山楂药材均以不饱和脂肪酸为主,其相对质量分数分别为59.10%、61.18%、63.08%、59.76%、60.76%。对河北、安徽、辽宁3个产地山楂核中的脂肪酸成分进行了较系统全面的研究,其脂肪酸以不饱和脂肪酸为主,相对质量分数分别为89.80%、61.59%、79.55%,均高于同一产地去核山楂中的不饱和脂肪酸相对质量分数。     

气相色谱法测定煤化工废水中酚类和脂肪酸的实验研究

建立了直接测定煤化工废水中酚类和短链脂肪酸的气相色谱分析方法,该法采用强极性毛细管柱,对脂肪酸和酚同时进行分析测定,用外标法进行定量计算。煤气化废水水样中各物质检出限在3 mg/L~10mg/L,标准曲线在考察质量浓度范围(0.01 g/L~10 g/L)内呈线性关系,相关系数在0.999 7以上,相对标准偏差≤7%。该方法无需复杂的前处理,操作简单易行,测定结果准确。     

鲩鱼脂肪酸的组成及其含量的GC-MS分析

采用气相色谱-质谱法分析了鲩鱼中脂肪酸的化学组成及各成分的含量。鲩鱼中的脂肪经石油醚提取、酸碱结合法甲酯化、GC-MS测定、总离子流图峰面积归一化法测定各组分相对含量。鲩鱼中检出26种脂肪酸,其中饱和脂肪酸含量为38.46%,不饱和脂肪酸61.54%。,含量较高的脂肪酸是亚麻油酸31.83%,油酸29.89%,棕榈油酸11.36%。     

Simultaneous Determination of Free Fatty Acids and Esterified Fatty Acids in Rice Oil by Gas Chromatography

Free fatty acids (FFA) in crude rice oil were selectively and stoichiometrically derivatized to fatty acid N,N-dimethylamides (FADMA) by catalytic condensation at 45 °C, and then esterified fatty acids (eFA) were directly converted to fatty acid methyl esters (FAME) at 37 °C. The mixture of FADMA and FAME formed in a single test tube was injected into the capillary column of a gas chromatograph (GC). No mutual contamination occurred between FFA and eFA, and reliability of the method was confirmed by comparison between GC data obtained by this method and by a conventional isolation method. The advantages of the present method are that no FFA isolation procedures are required, the reactions proceed under mild temperature conditions, and FFA and eFA can be analyzed simultaneously by GC.     

棉籽酸化油的理化性质及脂肪酸组成分析

采用气相色谱法分析了棉籽酸化油的脂肪酸组成,并对其理化性质进行了研究。分析结果表明,棉籽酸化油的含油率为91.33%,酸值为144.35mgKOH/g,碘值为116.58gI2/100g,皂化值为199.80mgKOH/g;其主要脂肪酸为棕榈酸(21.29%)、硬脂酸(2.29%)、油酸(23.72%)、亚油酸(50.23%)和亚麻酸(0.39%),其中不饱和脂肪酸的含量高达74%,具有很高的工业利用价值。     

Fatty Acids in Liver,Muscle and Gonad of three Tropical Rays including Non-Methylene-Interrupted Dienoic Fatty Acids

Scientific investigation of lipids in Elasmobranchs has been conducted mainly on shark species. Because rays seem to be neglected, this study was performed to examine the complete fatty acid (FA) composition with a particular interest for long-chain polyunsaturated FA (PUFA) content in different tissues of three ray species including parts usually discarded. The total FA and PUFA profiles of total lipids were determined in muscle, liver, and gonad of Rhinobatos cemiculus, Rhinoptera marginata, and Dasyatis marmorata, the most often caught ray species from the East Tropical Atlantic Ocean. Fifty FA were characterized as methyl esters and N-acyl pyrrolidides by gas chromatography/mass spectrometry, showing significant levels of 20:5n-3 (EPA) (up to 5.3%) and 22:5n-3 (DPA) (up to 7.3%), high levels of 20:4n-6 arachidonic (ARA) (4.8–8.6% of total FA) and 22:6n-3 (DHA) (up to 20.0%). The results show that muscle, liver and gonad of rays can provide high amounts of essential PUFA, specially DHA, for direct human nutrition or the food processing industry. High proportions of DHA were particularly found in all samples of R. cemiculus (11.6–20.0%), and in muscle and liver of D. marmorata (11.1–16.1%). Regarding the high amounts of (n-3) PUFA, this study shows that these rays deserve a better up-grading, including the normally discarded parts, and describes the occurrence of unusual NMID FA in all tissues studied. Five non-methylene-interrupted dienoic fatty acids (NMID FA) (0–3.4%) were reported, including previously known isomers, namely 20:2 Δ7,13, 20:2 Δ7,15, 22:2 Δ7,13, 22:2 Δ7,15, and new 22:2 Δ6,14. These acids are quite unusual in fish and unprecedented in rays. The 22:2 Δ6,14 acid occurred in gonads of male specimens of R. cemiculus at 2.9%.     

气相色谱-质谱联用法测定金属皂中的多环芳烃

建立了金属皂中16种美国环保局(EPA)优先监控的多环芳烃的气相色谱-质谱(GC/MS)联用测定方法,样品先用二甲基亚砜萃取,再用环己烷进行反萃取,经硅胶柱净化后,用GC/MS分离测定。优化了16种多环芳烃(PAHs)的分离测定条件,结果16种PAHs的平均回收率为75.32%￣98.72%,精密度实验相对标准偏差(RSD)为2.19%￣6.93%,检测限(S/N=5)为0.002￣0.010mg/kg。该方法灵敏度高、准确性好,完全可以满足金属皂中多环芳烃的检测要求。     

Polyhydroxy Fatty Acids Derived from Sophorolipids

Starting from 17-hydroxyoleic acid, which is readily available from acid alcoholysis of sophorolipids, several new polyhydroxy fatty acids have been synthesized. These compounds contain from 2 to 4 hydroxy groups, in some instances combined with other functional groups. The added hydroxy groups can be incorporated in the C₁₈ chain in a variety of geometries, for example spaced widely throughout the chain at C1, C8, and C17. This regiochemical control will be of use in structure/function studies involving materials constructed from these hydroxy fatty acids. A further benefit is that the hydroxy groups can be present in protected or free states. The principal reactions used to introduce extra hydroxy groups are selenium oxide-mediated allylic hydroxylation, osmium-catalyzed dihydroxylation, and borohydride reduction of a carboxylic ester. These new compounds are expected to be of use in a number of areas, but particularly as building blocks for polymers or components of lubricant formulations. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the US Department of Agriculture.     

Estimation of Protein and Fatty Acid Composition in Shell-Intact Cottonseed by Near Infrared Reflectance Spectroscopy

Rapid and accurate analysis of cottonseed protein content and the composition of fatty acids (especially, saturated fatty acids) is often required in cotton production and breeding programs. This study aimed to establish a set of effective estimation models for these parameters. Near infrared reflectance spectroscopy (NIRS) calibration equations using partial least-squares regression for protein concentration, oil concentration, and five fatty acids of shell-intact cottonseeds were established based on 90 varieties, and the prediction abilities of the calibration models were verified using 45 other varieties. The prediction abilities of the NIRS calibration equations were basically consistent with external validation results. Each equation was assessed based on the ratio of performance to deviation (RPD_p). Protein content and seed total fatty acid (STA) content had high RPD_p values (3.687 and 3.530, respectively), whereas cottonseed kernel total fatty acid (KTA) content, linoleic acid (18:2), stearic acid (18:0), myristic acid (14:0), and palmitic acid (16:0) exhibited relatively high RPD_p (2.866, 2.836, 2.697, 2.676, and 2.506, respectively). The calibration model for oleic acid (18:1) had a low RPD_p (1.945). The results indicated that NIRS can be used to rapidly determine contents of STA, KTA, protein, stearic acid (18:0), myristic acid (14:0), and palmitic acid (16:0) in shell-intact cottonseed.     

正常小鼠和肿瘤小鼠毛发中长链脂肪酸含量测定及比较

以正十七酸为内标 ,氯化氢 甲醇抽提和酯化 ,对正常、肿瘤、抗肿瘤小鼠毛发中长链脂肪酸——豆蔻酸、棕榈酸、棕榈油酸、油酸、硬脂酸和亚油酸进行毛细管柱气相色谱定量分析和比较。结果显示 :肿瘤小鼠或抗肿瘤小鼠毛发中长链脂肪酸含量明显升高 ,不饱和长链脂肪酸比例升高而饱和长链脂肪酸比例下降 ,提示毛发中不饱和长链脂肪酸尤其亚油酸与生物体内肿瘤的发生和存在有密切关系。本实验方法简单 ,所需样品量少 ,实验重现性好 ,回收率达定量分析要求。     

Analysis of Intact Cholesteryl Esters of Furan Fatty Acids in Cod Liver

Furan fatty acids (F‐acids) are a class of natural antioxidants with a furan moiety in the acyl chain. These minor fatty acids have been reported to occur with high proportions in the cholesteryl ester fraction of fish livers. Here we present a method for the direct analysis of intact cholesteryl esters with F‐acids and other fatty acids in cod liver lipids. For this purpose, the cholesteryl ester fraction was isolated by solid phase extraction (SPE) and subsequently analyzed by gas chromatography with mass spectrometry (GC/MS) using a cool‐on‐column inlet. Pentadecanoic acid esterified with cholesterol was used as an internal standard. GC/MS spectra of F‐acid cholesteryl esters featured the molecular ion along with characteristic fragment ions for both the cholesterol and the F‐acid moiety. All investigated cod liver samples (n = 8) showed cholesteryl esters of F‐acids and, to a lower degree, of conventional fatty acids. By means of GC/MS‐SIM up to ten F‐acid cholesteryl esters could be determined in the samples. The concentrations of cholesteryl esters with conventional fatty acids amounted to 78–140 mg/100 g lipids (mean 97 mg/100 g lipids), while F‐acid cholesteryl esters were present at 47–270 mg/100 g lipids (mean 130 mg/100 g lipids).     

The Divergent Immunomodulatory Effects of Short Chain Fatty Acids and Medium Chain Fatty Acids

Fatty acids are derived from diet and fermentative processes by the intestinal flora. Two to five carbon chain fatty acids, termed short chain fatty acids (SCFA) are increasingly recognized to play a role in intestinal homeostasis. However, the characteristics of slightly longer 6 to 10 carbon, medium chain fatty acids (MCFA), derived primarily from diet, are less understood. Here, we demonstrated that SCFA and MCFA have divergent immunomodulatory propensities. SCFA down-attenuated host pro-inflammatory IL-1β, IL-6, and TNFα response predominantly through the TLR4 pathway, whereas MCFA augmented inflammation through TLR2. Butyric (C4) and decanoic (C10) acid displayed most potent modulatory effects within the SCFA and MCFA, respectively. Reduction in TRAF3, IRF3 and TRAF6 expression were observed with butyric acid. Decanoic acid induced up-regulation of GPR84 and PPARγ and altered HIF-1α/HIF-2α ratio. These variant immune characteristics of the fatty acids which differ by just several carbon atoms may be attributable to their origins, with SCFA being primarily endogenous and playing a physiological role, and MCFA exogenously from the diet.     

GC-EI-MS Analysis of Fatty Acid Composition in Brain and Serum of Twitcher Mouse

Globoid cell leukodystrophy or Krabbe disease is an inherited autosomal recessive disorder caused by mutations in the galactosylceramidase gene. The objective of the study was to present information about the fatty acid (FA) composition of the brain and serum of twitcher mice, a mouse model of Krabbe disease, compared to wild type, in order to identify biomarker of disease progression. We defined the FA profiles by identifying the main components present in serum and brain using GC‐EI‐MS analysis. The FA percentage composition was measured and data were analyzed considering the disease and the mouse age as experimental factors. Significant correlations were established, both in brain and in serum, in the fatty acid percentage composition of twitcher compared to wild type mice. The most abundant saturated fatty acid in brain was the palmitic acid (C16:0) with mean values significantly increased in twitcher mouse (p = 0.0142); moreover, three monounsaturated, three polyunsaturated (PUFA) and a plasmalogen were significantly correlated to disease. In the serum highly significant differences were observed between the two groups for three polyunsaturated fatty acids. In fact, the docosahexaenoic acid (C22:6n3c) content was significantly increased (p = 0.0116), while the C20 PUFA (C20:3n6c and C20:5n3c) were significantly decreased in twitcher serum samples. Our study shows a specific FA profile that may help to define a possible pattern that could distinguish between twitcher and wild type; these data are likely to provide insight in the identification of new biomarkers to monitor the disease progression and thereby permit the critical analysis of therapeutic approaches.     

Dietary Fatty Acids Differentially Regulate Secretion of Adiponectin and Interleukin‐6 in Primary Canine Adipose Tissue Culture

The aim of this study was to determine the effect of n3 polyunsaturated fatty acids (PUFA) on canine adipose tissue secretion of adiponectin, interleukin‐6 (IL6), and tumor necrosis factor‐α (TNFα). Subcutaneous and omental visceral adipose tissue samples were collected from 16 healthy intact female dogs. Concentrations of adiponectin were measured in mature adipocyte cultures, and concentrations of IL6 and TNFα were measured in undifferentiated stromovascular cell (SVC) cultures following treatment with eicosapentaenic acid (EPA, 20:5n‐3), arachidonic acid (ARA, 20:4n‐6), or palmitic acid (PAM, 16:0) at 25, 50, or 100 μM. Secretion of adiponectin from mature adipocytes was higher (p < 0.001) following EPA treatment at 50 μM compared to control in subcutaneous tissue, and higher following EPA treatment compared to PAM treatment at 25 μM in both subcutaneous (p < 0.001) and visceral tissues (p = 0.010). Secretion of IL6 from SVC derived from subcutaneous tissue was lower following EPA treatment and higher following PAM treatment compared to control both at 50 μM (p = 0.001 and p = 0.041, respectively) and 100 μM (p = 0.013 and p < 0.001, respectively). These findings of stimulation of adiponectin secretion and inhibition of IL6 secretion by EPA, and stimulation of IL6 secretion by PAM, are consistent with findings of increased circulating concentrations of adiponectin and decreased circulating concentration of IL6 in dogs supplemented with dietary fish oil, and show that the effect of fish oil on circulating concentrations of adiponectin and IL6 is, at least partially, the result of local effects of EPA and PAM on adipose tissue.     

Quantification of Fatty Acids and their Regioisomeric Distribution in Triacylglycerols from Porcine and Bovine Sources Using 13C NMR Spectroscopy

The uptake of specific fatty acids in humans is dependent on their position on the glycerol backbone. There is a great interest in methods that can access this information fast and accurately. By way of high-resolution NMR, we have analyzed TAG extracted from pig and beef tissues and obtained quantitative data for the composition and regioisomeric distribution of all major unsaturated fatty acids usually found in these source materials, using a combination of manual integration and deconvolution of ¹³C NMR spectra. In addition, we have developed a method for determining composition and regioisomeric distribution of the two main saturated fatty acids found in pork (16:0, 18:0). The results are discussed in relation to species-specific genetic characteristics of fatty acid and TAG biosynthesis. The developed method could support decisions related to breeding for desired fatty acid profiles, and stimulate further methodology developments using high field NMR.     

气相色谱法测定食品油脂中的十八碳反式脂肪酸

反式脂肪酸是在油脂的加氢反应或高温精炼过程中伴随产生的一类不饱和脂肪酸,过多的食用这些成分可能会对人体健康产生危害。食品油脂中以十八碳反式脂肪酸最为常见。采用气相色谱法对食品中十八碳反式脂肪酸的检测进行了实验摸索,获得了一套准确度高、精确度好的方法,可应用于日常监督检测。     

Up to 21 Different Sulfur-Heterocyclic Fatty Acids in Rapeseed and Mustard Oil

Three sulfur-heterocyclic fatty acids (SHFA) had been tentatively identified in rapeseed oil in the late 1980s. In this study we aimed to enrich and verify the presence of potential SHFA in one sample of native rapeseed oil, refined rapeseed oil and mustard seed oil. Fifty-gram samples of the three oils were individually saponified and converted into methyl esters. The resulting samples were hydrogenated and subjected three times to urea complexation. The resulting extracts of native rapeseed oil and mustard oil contained 21 different SHFA with 18, 20, 22 or 24 carbons. The refined rapeseed oil contained only nine C₁₈-SHFA. Structure investigation of the SHFA was performed by gas chromatography with mass spectrometry (GC/MS) using methyl esters and also 3-pyridylcarbinol esters. A direct screening of non-enriched samples by GC/MS in the selected ion monitoring mode and by GC with flame photometric detector (sulfur-selective) verified that the SHFA were native compounds of the oils and no artefacts of the sample preparation. Similar abundances of the four isomer groups of SHFA with monoenoic fatty acids of the same carbon number in these and five further rapeseed and mustard samples indicated that these could be the precursors of the SHFA.     

A Facile and Efficient Method for the Synthesis of Labeled and Unlabeled Very Long Chain Polyunsaturated Fatty Acids

Several methods are available for elongation of fatty acid acyl chains. The present paper describes adaptation to the fatty acid field of a previously published protocol for manganese-based Wurtz type coupling of alkyl bromides. 22-Bromo-3(Z),6(Z),9(Z),12(Z),15(Z),18(Z)-docosahexaene, easily prepared from 4(Z),7(Z),10(Z),13(Z),16(Z),19(Z)-docosahexaenoic acid, was coupled to homologous ω-bromoesters by stirring for 4 hours at 40°C in the presence of manganese powder, a nickel catalyst and terpyridine. This afforded in yields of 70–75% a series of ω3-hexaenoates of chain lengths of 32–40 carbons. The corresponding fatty acids of >98% purity were obtained following saponification and final purification. By using methyl [2,2,3,3,4,4-²H₆]10-bromodecanoate as coupling partner it was possible to prepare a very long chain fatty acid in isotopically labeled form, i.e., [2,2,3,3,4,4-²H₆]14(Z),17(Z),20(Z),23(Z),26(Z),29(Z)-dotriacontahexaenoic acid. Also prepared were the monounsaturated long chain fatty acids 15(Z)-octadecenoic acid and 15(Z)-tetracosenoic acid. Very long chain fatty acids have been isolated from retina and other tissues and are of biological relevance. The methodology described will assist in further analytical and biological studies in this field.