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1.
This paper describes the preparation of a new type of branched vegetable oil and its methyl ester that involves the formation of acetonides. A facile and environmentally friendly synthesis has been found to produce acetonides that entails the use of ferric chloride as a catalyst and is conducted at room temperature. The products have been fully characterized with the help of model compounds, including elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR), and gas chromatography-mass spectrometry (GC-MS).  相似文献   

2.
Applying organic sources has been recommended to increase soil fertility and crop growth in sustainable production systems. Less information is available on the effects of organic inputs on soybean oil quality in the presence of nano-iron chelate. Field experiments were conducted during 2012 and 2013 to investigate the impact of organic, nano- and chemical sources on oil content and fatty acid composition of soybean (Glycine max [L.] Merr.). In split-plot arrangement of treatments, the main plots consisted of four fertilization systems: (F1): cattle manure, (F2): chemical fertilizers, (F3): cattle manure + chemical fertilizers, and (F4): control (without fertilizers). The subplots were (N1): soybean treated with nano-iron chelate fertilizer and (N2): control. Results showed that the highest oil yield was obtained in F3 treatment. The application of farmyard manure with nano-iron chelate significantly increased oleic acid compared to chemical fertilizers. The highest stearic acid and linolenic acid were observed in chemical fertilizer-contained treatments. Finally, the organic manure increased the oil quality of soybean.  相似文献   

3.
Specialty chemicals based on renewable resources are desirable commodities due to their eco-friendly nature and "green" product characteristics. These chemicals can demonstrate physical and chemical properties comparable to those of conventional petroleum-based products. Suitably functionalized amines in the triacylglycerol structure can function as an antioxidant, as well as an antiwear/antifriction agent. In addition, the amphiphilic nature of seed oils makes them an excellent candidate as base fluid. The reaction of amine and epoxidized seed oils in the presence of a catalyst almost always leads to different intra/intermolecular cross-linked products. In most cases, the triacylglycerol structure is lost due to disruption of the ester linkage. Currently, there is no reported literature describing the aminolysis of vegetable oil without cross-linking. Here the epoxy group of the epoxidized soybean oil has been selectively reacted with amines to give amine-functionalized soybean oil. The optimization procedure involved various amines and catalysts for maximum aminolysis, without cross-linking and disruption of the ester linkage. Diethylamine and ZnCl2 were found to be the best. NMR, IR, and nitrogen analysis were used to characterize the products.  相似文献   

4.
该研究应用生命周期评价方法,以大豆油和地沟油分别制备1 t生物柴油为研究对象,计算生物柴油全生命周期过程中的能源消耗和周期排放,结果表明:以大豆油为原料制备生物柴油全生命周期总能耗约为地沟油的2.65倍,且以地沟油为原料制备生物柴油过程中CO2、SO2、NOx、CO和粉尘各项排放与大豆油为原料时相比分别降低了82.92%、45.68%、94.91%、53.40%和90.61%。通过对制备生物柴油生命周期排放的废气和废物对环境造成的影响进行量化分析,结果表明以大豆油为原料时生命周期环境影响潜值约为地沟油的11.70倍,其数值分别为8.42和0.72,大豆油制备生物柴油过程中对环境的影响主要是全球性的变暖,地沟油制备生物柴油过程中对环境的影响主要是地区性的酸化。  相似文献   

5.
Single cells prepared from autoclaved soybeans and cellulase treatment of the cells were effective in digesting the cell walls of and extracting the oil from soybeans. The first cell wall of the soybean single cell was completely removed using cellulases; the thin and transparent second cell wall of the cell was swollen. Oil in the cell formed spherical or hemispherical oil drops, and oil leaking from the oil bodies was observed. The oil was almost retained within the second cell wall. Water-extractable substances were obtained at approximately >60% of the weight. Flotation of oil drops by centrifugation was easily done. Ambient n-hexane extraction was also possible; however, residual oil remained in the oil bodies. Protease or peptidase digested the structure of the oil bodies; however, separation of the oil and the hydrolysates was impossible. The oil from the oil bodies was obtained effectively (>85%) by pressing the single cells and/or cellulase-treated single cells.  相似文献   

6.
7.
大豆油体乳液稳定性和流变性分析   总被引:1,自引:1,他引:1  
研究大豆油体乳液的基本物理化学性质,将为其工业应用提供参考。以水为介质提取大豆油体,方法无毒,利于食用。对其在不同pH值(pH值2~8)、NaCl浓度(0~250?mmol/L)和加热处理(30~90℃,30?min)条件下的Zeta电位、平均粒径和乳析稳定性进行测定,并对其流变性进行考察。大豆油体乳液的Zeta电位为+20?mV~-40?mV(pH值2~8),等电点约为4.5。在pH值≤3和pH值≥6条件下,平均粒径均为0.4?μm左右;而在3<pH<6时,产生了乳析现象。在较高NaCl浓度下(>25?mmol/L),粒径较大和发生了乳析现象。大豆油体乳液在30~90℃加热处理时较稳定。大豆油体乳液呈现出弱凝胶的性质,其黏度随着油质量分数的降低而降低。研究表明,大豆油体乳液在一定的环境条件下是稳定的。  相似文献   

8.
A new route for the synthesis of fatty alcohol derivatives of hydroxytyrosol and other olive oil phenolic compounds was developed to allow the preparation of unsaturated derivatives. The biological activity of synthesized compounds was evaluated. Most of the compounds presented a significant antioxidant activity on low-density lipoprotein (LDL) particles. The activity of the tested products was significantly influenced by the number and position of unsaturations as well as modifications on the polar head of the synthesized compounds. Some of them presented modulation of food intake in rats and, due to their molecular similarity with CB(1) endogenous ligands, the endocannabinoid system and PPAR-α were also evaluated as potential targets. The pharmacodynamics could not be totally explained by CB(1) and PPAR-α receptor interactions because only two of the four compounds with biological activity showed a CB(1) activity and all of them presented low PPAR-α affinity, not justifying its whole in vivo activity. The hydroxytyrosol linoleylether (7) increased LDL resistance to oxidation with a capacity similar to that of hydroxytyrosol and was the most active in vivo compound with a hypophagic effect comparable to that of oleoylethanolamine. We consider that this compound could be a good lead compound for future drug development in obesity treatments.  相似文献   

9.
The two-step syntheses of the cyclic carbonates carbonated methyl oleate (CMO) and carbonated methyl linoleate (CML) are reported. First, synthesis of epoxides through well-precedented chemical reactions of unsaturated fatty methyl esters with hydrogen peroxide and formic acid was accomplished. Next, a carbonation reaction with a simple tetrabutylammonium bromide catalyst was performed, allowing the direct incorporation of carbon dioxide into the oleochemical. These syntheses avoid the use of the environmentally unfriendly phosgene. The carbonated products are characterized by IR, 1H NMR, and 13C NMR spectroscopy and studied by thermogravimetric analysis (TGA). Also reported is the synthesis of a similar cyclic carbonate from the commercially available 2-ethylhexyl epoxy soyate. These carbonates show properties that may make them useful as petrochemical replacements or as biobased industrial product precursors.  相似文献   

10.
11.
Ethyl esters (FAEE) and trideuterium-labeled methyl esters (d3-FAME) of fatty acids were prepared and investigated regarding their suitability as internal standards (IS) for the determination of fatty acids as methyl esters (FAME). On CP-Sil 88, ethyl esters of odd-numbered fatty acids eluted approximately 0.5 min after the respective FAME, and only coelutions with minor FAME were observed. Depending on the problem, one or even many FAEE can be added as IS for the quantification of FAME by both GC-FID and GC-MS. By contrast, d3-FAME coeluted with FAME on the polar GC column, and the use of the former as IS requires application of GC-MS. In the SIM mode, m/z 77 and 90 are suggested for d3-methyl esters of saturated fatty acids, whereas m/z 88 and 101 are recommended for ethyl esters of saturated fatty acids. These m/z values give either no or very low response for FAME and can thus be used for the analysis of FAME in food by GC-MS in the SIM mode. Fatty acids in sunflower oil and mozzarella cheese were quantified using five saturated FAEE as IS. Gravimetric studies showed that the transesterification procedure could be carried out without of loss of fatty acids. GC-EI/MS full scan analysis was suitable for the quantitative determination of all unsaturated fatty acids in both food samples, whereas GC-EI/MS in the SIM mode was particularly valuable for quantifying minor fatty acids. The novel GC-EI/MS/SIM method using fatty acid ethyl esters as internal standards can be used to quantify individual fatty acids only, that is, without determination of all fatty acids (the common 100% method), although this is present. This was demonstrated by the exclusive quantification of selected fatty acids including methyl-branched fatty acids, erucic acid (18:1n-9trans), and polyunsaturated fatty acids in cod liver oil and goat's milk fat.  相似文献   

12.
原料及制油工艺对花生毛油中塑化剂含量的影响   总被引:1,自引:0,他引:1  
为了探究油料品质及制油工艺对花生毛油中邻苯二甲酸酯类塑化剂(phthalatic acid esters,PAEs)的影响规律,对未脱皮花生仁和脱皮花生仁分别采用压榨法和浸出法提取花生毛油,对未脱皮和脱皮花生仁及其对应毛油中PAEs含量进行检测分析,研究原料品质和制油工艺对花生毛油中PAEs含量的影响。结果表明:未脱皮和脱皮花生仁中均含有PAEs且在制油过程向毛油中迁移和富集,在不同制油工艺中迁移率的差别致使不同毛油中PAEs含量也有明显差别。7个未脱皮花生仁样品中邻苯二甲酸二丁酯(dibutyl phthalate,DBP)、邻苯二甲酸二(2-乙基)己酯(di(2-ethtlhexyl)phthalate,DEHP)、邻苯二甲酸二异壬酯(diisononyl ortho-phthalate,DINP)和8种塑化剂总的(total content of 8 PAEs,∑8PAEs)质量分数分别为0.085~0.540、0.325~1.372、0.422~0.771和0.964~3.403 mg/kg。花生浸出毛油中DBP、DEHP、DINP及∑8PAEs平均含量是压榨毛油的1.39、1.23、1.16、1.22倍。花生仁脱皮制油可使毛油中DBP、DEHP、DINP、∑8PAEs含量分别降低33.0%~36.4%、26.7%~29.4%、15.0%~18.7%、22.5%~23.0%。在花生油生产尤其是炒香型花生油生产时,严格对花生仁原料中PAEs含量进行监控,同时采用花生脱皮压榨取油,对花生油产品的PAEs风险防范和控制有重要意义。研究结果可为企业生产高品质花生油,降低PAEs风险提供参考。  相似文献   

13.
Two direct methylation procedures often used for the analysis of total fatty acids in biological samples were evaluated for their application to samples containing fatty amides. Methylation of 5 mg of oleamide (cis-9-octadecenamide) in a one-step (methanolic HCl for 2 h at 70 degrees C) or a two-step (sodium methoxide for 10 min at 50 degrees C followed by methanolic HCl for 10 min at 80 degrees C) procedure gave 59 and 16% conversions of oleamide to oleic acid, respectively. Oleic acid recovery from oleamide was increased to 100% when the incubation in methanolic HCl was lengthened to 16 h and increased to 103% when the incubation in methoxide was modified to 24 h at 100 degrees C. However, conversion of oleamide to oleic acid in an animal feed sample was incomplete for the modified (24 h) two-step procedure but complete for the modified (16 h) one-step procedure. Unsaturated fatty amides in feed and digesta samples can be converted to fatty acid methyl esters by incubation in methanolic HCl if the time of exposure to the acid catalyst is extended from 2 to 16 h.  相似文献   

14.
大豆色拉油包水乳化液乳化技术研究   总被引:1,自引:0,他引:1  
目前在生物医学领域已进行了白蛋白及胰岛素的控制释放的壳聚糖/海藻酸钠微胶囊研究,但其制备方法仅适合于实验室生产。用标准乳化剂确定了油水体系的HLB值,用油水体系的HLB值确定了单甘油酯的HLB值。以HLB值为依据,考虑乳化剂分子的结构、分子量及亲水亲油基的种类,选择乳化剂配对,讨论了不同乳化剂配对乳化效率的机理,探讨了选择乳化剂配对的方法,研究了乳化过程参数对乳化效率的影响。试验结果表明:最佳的乳化工艺参数是乳浊液配方为5.5 g复合乳化剂:7.2 g大豆色拉油:47.2 g水溶液, 搅拌时间为20 min,搅拌转速1000 r/min。该研究是大规模制备壳聚糖/海藻酸钠微胶囊的基础工作。  相似文献   

15.
Hydrogenated soybean oil was obtained after 10 min of hydrogenation with 0.5% selective type Ni catalyst at 230 degrees C, a hydrogenation pressure of 0.049 MPa, and an agitation rate of 300 rpm. The conjugated linoleic acid isomers in the hydrogenated soybean oil were isolated by using a silver ion-impregnated HPLC. Gas chromatography-mass spectrometry of 4,4-dimethyloxazoline (DMOX) derivatives of the isolated conjugated linoleic acid isomers were carried out for the identification of their chemical structures. By interpreting the mass spectra of the DMOX derivatives of conjugated linoleic acid isomers isolated by silver ion-impregnated HPLC, 20 different conjugated linoleic acid isomers present in hydrogenated soybean oil were identified. This is the first report for the mass spectrometric identification of the conjugated linoleic acid isomers present in hydrogenated vegetable oil.  相似文献   

16.
基于近红外分析技术检测大豆脂肪酸含量的研究   总被引:4,自引:2,他引:4  
为探索近红外光谱技术在大豆脂肪酸测试中的应用,寻找一种快速的检测方法。以黑龙江省各地的25份大豆品种为材料,采用Perten8620型近红外光谱仪对搜集到的样品进行扫描并得到光谱数据,采用多元线性回归(MLR)和偏最小二乘法(PLS)对试验数据进行了多元统计分析。结果表明:在1700~2300 nm范围内检测大豆脂肪酸含量是可靠的,并且PLS模型的性能优于MLR模型。该文还对近红外仪中的滤光片组合作了初步探讨,表明不同的滤光片组合对测量精度有一定影响。  相似文献   

17.
The composition and structures of triacylglycerols (TAG) in a commercially prepared hydrogenated soybean oil margarine basestock [iodine value (IV) 65, 39.7% trans fatty acids] were determined by high-performance liquid chromatography (HPLC) in tandem with atmospheric pressure chemical ionization (APCI) mass spectrometry (MS). The basestock was separated by preparative HPLC into four fractions. Fractions 1 and 4, constituting approximately 8% of the total, were shown to consist of LOO, PLO, and LLS and OSS and PSS, respectively (where L = linoleic, O = oleic, S = stearic, and P = palmitic). APCI will not distinguish between O, oleic cis C18:1, and E, elaidic trans C18:1. Thus, O and E may be used interchangeably in discussion of TAG isomer structures. Fraction 2 consisted of OOO and POO. Fraction 3 consisted of OOO, POO, OOS, and POS. About 80% of the total triglycerides consisted of OOO, POO, and OOS. The trans fatty acid content of the fractions was determined, and the results showed that 92% of the total trans content was found in fractions 2 and 3. A shortening basestock (IV 81.7, 31.8% trans fatty acids) was partially characterized.  相似文献   

18.
The effect of riboflavin or fatty acid methyl esters on cholesterol photooxidation was studied. Samples containing cholesterol, either alone or in combination with riboflavin or fatty acid methyl esters, were illuminated at 25 degrees C in an incubator for 28 days. The various cholesterol oxidation products (COPs) and cholesterol were analyzed by gas chromatography-mass spectrometry (GC-MS), and riboflavin was determined by HPLC. Results showed that the presence of riboflavin or fatty acid methyl esters facilitated production of COPs and degradation of cholesterol, and the degradation fits a first-order model. The COPs formed during light storage included 7 alpha-OH, 7 beta-OH, 7-keto, 3,5-cholestadien-7-one, 5,6alpha-EP, and 5,6beta-EP. The addition of riboflavin caused formation of 3,5-cholestadien-7-one through dehydration of 7-keto, whereas in the presence of docosahexaenoic acid methyl ester, the formation of 5,6alpha-EP or 5,6beta-EP was favored. Riboflavin was more effective for generation of COPs than fatty acid methyl esters.  相似文献   

19.
The aim of the present work was to establish the limiting factors affecting the biosynthesis of volatile esters present in virgin olive oil (VOO). Oil volatile fractions of the main Spanish olive cultivars, Arbequina and Picual, were analyzed. It was observed that acetate esters were the most abundant class of volatile esters in the oils, in concordance with the high content of acetyl-CoA found in olive fruit, and that the content of C6 alcohols is limited for the synthesis of volatile esters during the production of VOO. Thus, the increase of C6 alcohol availability during VOO production produced a significant increase of the corresponding ester in the oils in both cultivars at two different maturity stages. However, the increase of acetyl-CoA availability had no effect on the VOO volatile fraction. The low synthesis of these C6 alcohols seems not to be due to a shortage of precursors or cofactors for alcohol dehydrogenase (ADH) activity because their increase during VOO production had no effect on the C6 alcohol levels. The experimental findings are compatible with a deactivation of ADH activity during olive oil production in the cultivars under study. In this sense, a strong inhibition of olive ADH activity by compounds present in the different tissues of olive fruit has been observed.  相似文献   

20.
Approaches for the capillary gas chromatographic (GC) based analysis of intact plant stanyl esters in enriched foods were developed. Reference compounds were synthesized by enzyme-catalyzed transesterifications. Their identities were confirmed by means of mass spectrometry. Using a medium polar trifluoropropylmethyl polysiloxane stationary phase, long-chain plant stanyl esters could be separated according to their stanol moieties and their fatty acid chains. Thermal degradation during GC analysis was compensated by determining response factors; calibrations were performed for ten individual plant stanyl esters. For the analysis of low-fat products (skimmed milk drinking yogurts), the GC separation was combined with a "fast extraction" under acidic conditions. For fat-based foods (margarines), online coupled LC-GC offered an elegant and efficient way to avoid time-consuming sample preparation steps. The robust and rapid methods allow conclusions on both, the stanol profiles and the fatty acid moieties, and thus provide a basis for the authentication of this type of functional food ingredients.  相似文献   

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