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1.
The Physical and Rheological Parameters of Transesterificated Fats The model mixtures of triacylglycerols containing the various ratio of saturated and unsaturated fatty acids were prepared by noncontroling basic catalyzed interesterification. According to the ratio of palmitic acid and stearic acid three types of mixtures varying in the content of trisaturated triacylglycerols: a) tripalmitylglycerol, b) monopalmityldistearylglycerol, c) tristearylglycerol were prepared. The physical and rheological properties of transesterificated and nontransesterificated mixtures (especially the melting point, the solidification point, the solid fat content and the yield value – Haighton) were compared. These parameters were correlated in dependence on the ratio of saturated and unsaturated fatty acids and especially on the ratio of the content of palmitic acid and stearic acid which seemed to be of a great value in intended system.  相似文献   

2.
The composition and positional distribution of fatty acids in phospholipids isolated from four locations of a hog carcass is presented. Variations in fatty acid composition of phospholipids were found depending upon the location in the carcass. The total unsaturated fatty acid content averaged 34.3 mole % for lecithin, 52.5 mole % for phosphatidylethanolamine, 40.3 mole % for phosphatidylserine and 41.3 mole % in sphingomyelin. The cephalins had a much higher percentage of polyunsaturated fatty acids than lecithin. The chief saturated fatty acid in lecithin and sphingomyelin was palmitic and in cephalins it was stearic. A snake venom enzyme preparation(Crotalus adamanteus) hydrolyzed primarily unsaturated fatty acids in phosphoglycerides and the higher the percentage of unsaturation within the fatty acid the higher percentage of hydrolysis occurred. The unsaturated fatty acids were found chiefly at the theβ-position and the saturated fatty acids at thea-position in the phosphoglycerides. Michigan State Agricultural Experiment Station Publication No. 3389. Supported by the U.S. Public Health Service Research Grant No. GM 08801-03.  相似文献   

3.
Fatty acid compositions of oleaster pulp and pit oils were determined by gas chromatography in 4 samples of different varieties. Pit oils were highly unsaturated, containing >90% linoleic, oleic, and linolenic acids, as well as traces of palmitoleic acid. Saturated fatty acids consisted of palmitic and stearic acids with traces of arachidic acid. Pulp oils showed fatty acid compositions entirely different from that of pit oils. They contained 9 saturated fatty acids, C12 to C24, some of them with high quantities, up to 34.9%, of the total fatty acids. Unsaturated fatty acids, mainly oleic and linoleic, with low quantities of palmitoleic and linolenic acids composed about one-third of the total fatty acids.  相似文献   

4.
金高娃  章飞芳  薛兴亚  徐青  梁鑫淼 《精细化工》2006,23(8):760-761,770
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。  相似文献   

5.
The seeds of moth bean (Vigna aconitefolia) were found to contain 4.5 % of lipid. Fractionation of this lipid by silicic acid column chromatography yielded 44.5 % neutral lipids (NL), 23.4 % glycolipids (GL) and 32.1 % phospholipids (PL). Fatty acid composition of the total lipid and lipid fractions showed that palmitic acid (37.3-54.7 %), stearic acid (7.8-8.0%) oleic acid (6.8-13.9 %) linoleic acid (23.1-35.6 %) and linolenic acid (3.0-10.0%) are the major fatty acids. The phospholipid fraction was found to be different from the rest in containing higher palmitic acid (54.7%) and lower unsaturated fatty acids.  相似文献   

6.
TheMoringa peregrina kernel contains 1.8% moisture, 54.3% oil, 22.1% protein, 3.6% fiber, 15.3% carbohydrate and 2.5% ash. The composition and characteristics of the extracted oil were determined. Gas liquid chromatography of methyl esters of the fatty acids shows the presence of 14.7% saturated fatty acids and 84.7% unsaturated fatty acids. The fatty acid composition is as follows: palmitic 9.3%, palmitoleic 2.4%, stearic 3.5%, oleic 78.0%, linoleic 0.6%, linolenic 1.6%, arachidic 1.8% and behenic 2.6%.  相似文献   

7.
Ten soybean genotypes grown in 1992 with seed size ranging from 7.6 to 30.3 g/100 seeds and maturity group V or VI were selected and tested for oil and protein content and for fatty acid composition. In these germplasm, protein varied from 39.5 to 50.2%, oil, 16.3 to 21.6%, and protein plus oil, 59.7 to 67.5%. Percentages of individual fatty acids relative to total fatty acids varied as follows: palmitic, 11.0 to 12.8; stearic, 3.2 to 4.7; oleic, 17.6 to 24.2; linoleic, 51.1 to 56.3 and linolenic, 6.9 to 10.0. Seed size showed no significant correlations with individual saturated fatty acids, protein or oil content. However, significant correlations were found between seed size and individual unsaturated fatty acids: positive with oleic, and negative with linoleic and linolenic. Oil and protein content were negatively correlated with each other. Among the major fatty acids, only the unsaturated were significantly correlated with each other: negative between oleic and linoleic or linolenic, and positive between linoleic and linolenic. A subsequent study with soybeans grown in 1993 generally confirmed these findings. Variation in relative percentages of unsaturated fatty acids andr values for most pairs of relationships were even higher than those obtained from the 1992 crop. Presented at the 85th AOCS Annual Meeting and Expo, Atlanta, Georgia, May 8–12, 1994.  相似文献   

8.
Physico-chemical analysis of seven seeds of indigenous species of plants belonging to six different botanical families have been carried out with the help of UV, IR, TLC-GLC techniques. All the seed oils were found in agreement with the simple fatty acid composition i.e. linoleic-oleic-palmitic type. The chief components among unsaturated acids in the six seed oils are oleic and linoleic acids together forming 40.0-86.0 %. Polygonum sp. surprisingly is found to have combined content of oleic and linoleic acid 13.3 % only but having unexpected high amount of linolenic acid (37.8 %). Among saturated acids, palmitic acid was predominant acid found in the range of 10.0-483 %. This chemical screening of seed oils reveals that the species producing highly unsaturated oils merit attention for utilization as minor seed oils.  相似文献   

9.
The common unsaturated fatty acids present in many vegetable oils (oleic, linoleic and linolenic acids) can be quantitated by 1H‐nuclear magnetic resonance spectroscopy (1H‐NMR). A key feature is that the signals of the terminal methyl group of linolenic acid are shifted downfield from the corresponding signals in the other fatty acids, permitting their separate integration and quantitation of linolenic acid. Then, using the integration values of the signals of the allylic and bis‐allylic protons, oleic and linoleic acids can be quantitated. The procedure was verified for mixtures of triacylglycerols (vegetable oils) and methyl esters of oleic, linoleic and linolenic acids as well as palmitic and stearic acids. Generally, the NMR (400 MHz) results were in good agreement with gas chromatographic (GC) analyses. As the present 1H‐NMR‐based procedure can be applied to neat vegetable oils, the preparation of derivatives for GC would be unnecessary. The present method is extended to quantitating saturated (palmitic and stearic) acids, although in this case the results deviate more strongly from actual values and GC analyses. Alternatives to the iodine value (allylic position equivalents and bis‐allylic position equivalents) can be derived directly from the integration values of the allylic and bis‐allylic protons.  相似文献   

10.
Physiological Effect of Various Mixtures of Oleic, Linoleic and Linolenic Acids on Growing Pigs: 2. Influence on Depot Fats and Blood Lipids At the end of the feeding trials described extensively in the first contribution, from all animals saddle bacon and leaf fat as well as serum lipids have been investigated on effects of the various food fats. Earlier results have been confirmed according to which the increased supply of unsaturated fatty acids results in an increase of the content in depot fat and in a decrease of palmitic and stearic acid. The storage of linoleic and linolenic acids is linked to the consumed amount of these acids in a linear way. Some hints have been found for the occurrence of yellow fat desease that besides the deficiency of vitamin E an enzyme activating effect of higher amounts of linolenic acid may be responsible. Furthermore the attacked animals showed a linear dependence of the fat content in the yellow tissue from its peroxide value. As well linolenic acid as oleic acid led to a significant decrease of the serum triglycerides. Besides, linolenic acid lowered the content of serum cholesterol, whereas linoleic acid caused a significant increase of the HDL content.  相似文献   

11.
Neutral, glyco- and phospholipids of garlic were resolved into their component fractions by thin layer chromatography. Neutral lipids contained considerable quantities of monoglycerides (18.5%), diglycerides (14.2%), sterols (16.3%) and triglycerides (41.5%) respectively. The phospholipid fraction was rich in phosphatidyl choline (23.5%), phosphatidyl ethanolamine (17.9%), lysophosphatidyl choline (11.8%) and lysophosphatidyl ethanolamine (8.2%). Digalactosyl diglyceride (10.1%), sterol glycoside (15.6%), cerebrosides (8.1%), acylsterol glycoside (38.6%) and monogalactosyl diglyceride (22.5%) were the major components of the glycolipids of garlic. Lauric, myristic, palmitic and linoleic acids constituted the major fatty acids of monoglycerides, diglycerides and free fatty acid fractions whereas palmitic, linoleic and linolenic acids were the major fatty acids of triglycerides. Palmitic and linoleic acids were the major fatty acids of garlic phospholipids. Except the acylsterol glycoside fraction glycolipids were rich in lauric, palmitic, linoleic and linolenic acids; palmitic acid was the only major fatty acid of acylsterol glycosides.  相似文献   

12.
In their natural form, fats and vegetable oils melt at temperatures useful for thermal energy storage. Incremental improvement of their heat release characteristics could pave the way for commercial applications as phase change materials (PCM). These chemicals could provide a biomaterial alternative to a technology dominated by paraffin and salt products.Mixture heats of fusion and melting points were evaluated for single acid derivatives of stearic, palmitic, and oleic acids to develop a fundamental understanding of the solid-liquid transition and to better understand how to convert natural compositions to useful PCM products. Many mixtures of monoacid derivatives of a single fatty acid formed single sharp solid-liquid phase transitions useful for PCM applications. These mixtures also qualitatively exhibited freezing point depression therein allowing the mixture composition to be used as a means to control the temperature of the phase transition. In mixtures of monoacid derivatives from different fatty acids, melting occurred over wider temperature ranges with eventual separation of the solid-liquid transition to at least two different events. This work demonstrates that it is possible to fully convert natural fatty acid mixtures into high performance phase change materials.  相似文献   

13.
Summary Organic soil that had gradually accumulated on cotton garments and was unremovable by normal washing procedures was analyzed for free and combined fatty acids by gas-liquid chromatography. The fatty acid composition of this material was similar to sebum and hair fat and was remarkably uniform although from several different sources and geographical locations. The predominant fatty acids were C15, C16, and C18 straight-chain acids. More than 30% of the total fatty acid was palmitic acid. The amount of oleic acid was considerably less than is reported for hair and skin fat. No linoleic acid or linolenic acid was detected. The small amount of unsaturated acids is probably the result of their oxidation to polymers and other oxidation products. The amount of free fatty acids was very small because they were converted to insoluble heavy metal soaps. Most of the combined fatty acids were present as esters,i.e., triglycerides.  相似文献   

14.
The fatty acid distribution in the seed flour from 31 Vicia taxa distributed throughout southern Spain was analyzed by gas chromatography. Fatty acids ranged from myristic acid to araquidic acid. Linoleic acid (from 28.7 to 66.3% of the fatty acids), oleic acid (from 7.2 to 32.5% of the fatty acids) and linolenic acid (from 2.7 to 16.6% of the fatty acids) were the most abundant among unsaturated ones and palmitic acid among saturated ones. The total unsaturated to saturated fatty acids ratio ranged between 2.6 in V. hirsuta and 4.2 in V. hybrida. Polyunsaturated to monounsaturated fatty acids ratio ranged between 1.3 in V. ervilia and 9.0 in V. pyrenaica. The ω-6 to ω-3 ratio ranged between 1.7 in V. articulata and 17.3 in V. faba. The fatty acids distribution observed in the Vicia species studied supports the use of these plants as a source of important dietary lipids.  相似文献   

15.
About 60% of the total sterols in the cotton bud appeared in the free state; the esterified sterol glycosides contained about 50% saturated fatty acids, largely palmitic acid; the principal unsaturated fatty acid was linolenic acid. β-Sitosterol was the major sterol in all classes of sterol derivatives. The sugar moiety of the esterified sterol glycosides and the sterol glycoside was galactose. Efforts are continuing to evaluate the minor sterols of cotton buds, some of which appear to be hydroxylated ecdysones, and to study their relationship to the development of the Boll weevil,Anthonomus grandis Boheman.  相似文献   

16.
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 %。  相似文献   

17.
Any new crop for which there is a market, and which appears to be adapted to the region, would be attractive to replace nonprofitable traditional crops in Northwestern Argentina. Chia (Salvia hispanica L.) is especially attractive because it can be grown to produce oil for both food and industry. The fatty acids of chia oil are highly unsaturated, with their main components being linoleic (17–26%) and linolenic (50–57%) acids. Seeds from a chia population harvested in Catamarca were sown in five Northwestern Argentina locations. The oil from the chia seeds produced under these five field conditions was measured. Linolenic, linoleic, oleic, palmitic, and stearic fatty acid contents of the oil were determined by gas chromatographic analysis. The results showed variations in oil content, and the oleic, linoleic, and linolenic fatty acid concentrations of the oil were significantly affected by location.  相似文献   

18.
建立了分析越南安息香种子油、果实和果壳的脂肪酸组成的在线甲基化-气相色谱法。将微克级的安息香样品与2μL衍生化试剂三甲基氢氧化硫(0.2 mol/L)加入裂解器,在350℃下瞬间反应,由气相色谱在线检测到8种脂肪酸甲酯成分,主要有棕榈酸( C16∶0)、硬脂酸( C18∶0)、油酸( C18∶1)、亚油酸( C18∶2)和亚麻酸( C18∶3),不饱和脂肪酸含量在84.5%以上,其中亚油酸含量最高,达47.29%。5次平行测定的相对标准偏差( RSD)小于3.81%。并结合相似性分析法比较了4种不同产地的安息香种仁与6种食用油的脂肪酸组成,相似性结果表明不同产地的安息香种仁的脂肪酸组成相似,其脂肪酸组成与食用植物油相近,与玉米油的组成分布最为接近,相似系数在0.987~0.990,且越南安息香种子中人体必需的多不饱和脂肪酸含量( C18∶2和C18∶3)与大豆油和葵花籽油相近,高于一般植物油,具有较高的营养价值。结果表明该法简便、快速、准确,适合越南安息香种子油脂的测定。  相似文献   

19.
The genetic diversity in seed lipid and fatty acid composition in nine accessions of sesame, comprising six cultivated and three wild relatives, was studied and compared. Seed oil content was 53.23–55.12% in cultivated and 53.35–58.56% in wild accessions. The principal fatty acids in the accessions were palmitic, stearic, oleic (OLE), linoleic (LIN) and linolenic (LIL) acids, of which lower OLE and higher LIN acids were observed in all the accessions. Principal component analysis revealed that OLE acid, total unsaturated fatty acids, total saturated fatty acids (SFAs), LIN acid and the unsaturated to SFA ratio had the highest loading in the first component, which accounted for 54.01% of the total variation. For the second principal components, lauric, palmitoleic, capric, lignoceric, arachidic and LIL acids had the highest loading, accounting for 26.94% of the total variation. Three principal components explained 89.01% of the total variation. The dendrogram generated by the UPGMA cluster analysis grouped the nine accessions into five distinct clusters, indicating genetic diversity; this can be used to plan crosses and maximise the expression of heterosis. Practical applications : This research work provides information on the fatty acid profile of seed oil from nine morphologically distinct accessions of sesame selected from thirty‐three accessions collected in 2003. This is intended to establish genetic diversity on the basis of fatty acid profile, identify accessions with high seed oil quality that may be adopted for large scale cultivation in Nigeria and justify the suitability of the nine accessions in serving as base materials in the ongoing breeding efforts for sesame seed oil quantity and quality improvement.  相似文献   

20.
混合脂肪酸的分离   总被引:17,自引:0,他引:17  
陈永  赵辉  江鸿  曹红霞  康定学 《化学世界》2000,41(3):156-159
以一般油脂加工副产物十八碳混合脂肪酸为原料,采用配合结晶梯度冷冻反萃取分离技术,不经任何热处理以避免聚合作用的发生,使混合脂肪酸中的饱和脂肪酸与不饱和脂肪酸分离,同时将不饱和脂肪酸分成油酸和(亚油酸+亚麻酸)两组分。后者含量可达95%以上。  相似文献   

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