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1.
用乙醚/正已烷混合溶剂萃取柑籽中的脂肪酸甘油酯,用KOH-CH_3OH法甲酯化,以毛细管色谱/质谱/计算机法测定其脂肪酸组成,共检出7种脂肪酯,其中以棕榈酸(35.48%)、油酸(26.6%)及亚油酸(27.27%)为主。  相似文献   

2.
石榴籽中脂肪酸成分分析   总被引:12,自引:0,他引:12  
采用两种方法对石榴籽中的脂肪酸进行了甲酯化,所得脂肪酸甲酯经GC-MS分析.方法一共检测出14种脂肪酸,主成分为油酸、亚油酸、山嵛酸、棕榈酸、硬脂酸和二十碳烯酸;方法二共检测出24种脂肪酸,主成分为棕榈酸、硬脂酸、花生酸、山嵛酸、油酸、亚油酸、二十碳烯酸等.其中的山嵛酸等多种饱和脂肪酸均为首次从石榴籽中鉴定出.  相似文献   

3.
奶油甘油三酯的毛细管气相色谱-EI质谱分析   总被引:1,自引:0,他引:1  
以HP_5MS30m×0.25mm×0.25μm毛细管柱分离奶油中各甘油三酯 ,通过各自EI质谱确定其组成 ,共鉴定出108种甘油三酯 ,其中以丁酸双棕榈酸三甘油酯 (8.2% ,峰面积百分比 ,下同 )、癸酸双棕榈酸三甘油酯 (7.9% )、月桂酸双棕榈酸三甘油酯 (7.7% )、肉豆蔻酸双棕榈酸三甘油酯 (6.9% )、丁酸棕榈酸油酸三甘油酯 (6.2% )、丁酸棕榈酸硬脂酸三甘油酯 (5.9% )为主  相似文献   

4.
GC/MS 法测定超临界 CO2 萃取茼蒿籽油   总被引:2,自引:0,他引:2  
利用GC/MS分析了超临界CO2萃取茼蒿籽油的成分组成,共检出32种成分。茼蒿籽油主要由亚油酸(含量68.32%)、棕榈酸(10.80%)、油酸(6.39%)和长碳链脂肪酸组成;茼蒿籽油还含甾类(4.76%)和丰富的维生素E(3.9mg/g);研究了茼蒿籽油的理化特征。  相似文献   

5.
甲鱼油脂肪酸组成的研究   总被引:12,自引:2,他引:12  
用热提取方法抽取出甲鱼油,用KOH-CH3OH酯交换法甲酯化处理,以色谱/质谱方法测定脂肪酸的组成。共鉴定出21种脂肪酸,其中以棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸、二十碳五烯酸(EPA)、二十二碳五烯酸(DHA)为主  相似文献   

6.
痕量动物油和植物油的区分检验研究   总被引:2,自引:0,他引:2  
采用碱催化甲酯化的前处理方法,应用气相色谱-质谱联用技术对动物油和植物油的区分检验进行了研究。实验检出了6种主要脂肪酸:肉豆蔻酸、棕榈油酸、棕榈酸、亚油酸、油酸、硬脂酸。分析了动物油与植物油在成分及相对含量上的差异,并且找出了动物油和植物油在不饱和度上的差别。根据动物油与植物油的差异点,可以对动物油和植物油进行区分。  相似文献   

7.
桃核中脂肪酸成分分析   总被引:3,自引:0,他引:3  
:通过GC-MS方法对桃核(核壳,桃仁,种皮)中的脂肪酸化学成分进行分析。鉴定出各种脂肪酸成分及其相对含量,主要成分为棕榈酸,硬酯酸,亚油酸,亚麻酸,油酸等。  相似文献   

8.
运用水蒸气蒸馏和乙醇提取两种方法分别提取茭白中的化学成分,气相色谱-质谱联用技术进行分离鉴定,面积归一法进行定量分析。并对两种方法所得结果进行比较,分析其中的差异之处。结果显示,水蒸气蒸馏提取物中共分离出106种组分(占总峰面积的82.07%),其中棕榈酸(16.89%)、己二酸二(2-乙基己)酯(6.39%)、油酸酰胺(5.64%)、亚油酸(3.84%)和油酸(3.64%)为主要组分。乙醇提取物中共分离出89种组分(占总峰面积的91.75%),其中棕榈酸(33.71%)、油酸(11.24%)、2-羟基-1-(羟甲基)棕榈酸乙酯(6.84%)、反油酸乙酯(4.93%)和亚油酸乙酯(3.88%)为主要成分。还鉴定出香兰素、月桂酸、茉莉酸等香味成分,以及花生四烯酸等活性组分。结果表明,茭白中的化学成分十分丰富,两种方法提取的成分及其总量存在一定差异。  相似文献   

9.
低酚棉籽仁中脂肪酸成分的研究   总被引:4,自引:0,他引:4  
采用气相色谱法测定了9个低酚棉品种中棉籽仁的脂肪酸组成及相对含量。样品所含主要脂肪酸为棕榈酸、油酸、亚油酸。其中亚油酸含量最高,为58.90%~64.88%。与普通棉籽仁进行对比的结果表明,两者脂肪酸组成一致,但低酚棉的亚油酸与不饱和脂肪酸的平均含量均高于普通棉  相似文献   

10.
该文研究了血府逐瘀汤对颅脑损伤大鼠血浆代谢组的影响,采用气相色谱-质谱联用(GC-MS)技术对治疗组、模型组以及假手术组的血浆代谢物进行检测,定性定量分析了43种重要的代谢物。模型组和假手术组的t检验(t-test)结果显示13种代谢物存在显著差异。正交偏最小二乘-判别分析(OPLS-DA)分析结果也显示模型组和假手术组代谢差异明显。结合变量的投影重要性指标(VIP)及t检验结果,筛选出乳酸、组氨酸、棕榈酸、色氨酸、亚油酸、油酸、硬脂酸作为生物标志物。观测7种标志物在治疗组中第1、3、7、14 d的变化情况。结果显示:治疗组中乳酸、组氨酸、棕榈酸、亚油酸、硬脂酸的相对浓度逐渐降低,色氨酸的相对浓度先降低后升高,油酸的相对浓度先升高后降低,且7种代谢物的相对浓度在第14 d时均接近于假手术组的水平。表明血府逐瘀汤对颅脑损伤具有一定的治疗作用,乳酸、组氨酸、棕榈酸、色氨酸、亚油酸、油酸、硬脂酸7种代谢物可以作为生物标志物监测颅脑损伤的治疗效果及恢复情况。  相似文献   

11.
In order to obtain a rapid method that can detect adulteration of butter fats with cheaper vegetable fats, the use of NIR spectroscopy and multivariate modelling was explored. For model building and validation, an extensive set of samples was collected, consisting of 152 butter samples, 42 oils and 200 blends thereof. Variations in butter fat composition are reflected in distinct NIR spectral regions. Principal components analysis and partial least square discriminant analysis was used to inspect the variation within the sample set. As reference values for training partial least squares models, butter fat levels as declared by suppliers were taken, as well as C4:0 fatty acid levels as measured directly by GC. All samples were used for training, except for 100 blends, which were used later for validation. Different pre-processing and PLS approaches were explored, resulting in models that had a RMSEPs for butter fat and C4:0 fatty acid level in the range of 4.3-8.2 and 0.33-0.38% (w/w), respectively. The performance of NIR in assessment of C4:0 fatty acid levels is lower as for GC, but this disadvantage is outweighed by shorter measurement times and the lower skill levels required. Furthermore NIR is able to assess overall levels of butter fat, in addition to the indirect indicator provided by the C4:0 fatty acid level.  相似文献   

12.
Quantitative analyses of fatty acids from five triacylglycerol products, coconut oil, palm kernel oil, palm oil, lard and cocoa butter, were carried out using two analytical methods: matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and gas chromatography (GC), in an effort to validate the application of MALDI-TOFMS in quantitative fatty acid analysis. For the GC analysis, transmethylated products were used, whereas, for the MALDI-TOF analysis, saponified products were used. Under MALDI-TOF conditions, the acids were detected as sodiated sodium carboxylates [RCOONa + Na](+) consistent with the mode of ionization that was previously reported. Thus, the MALDI-TOF mass spectrum of saponified coconut oil showed the presence of sodiated sodium salts of caprylic acid (7.5 +/- 0.67, m/z 189), capric acid (6.9 +/- 0.83, m/z 217), lauric acid (47.8 +/- 0.67, m/z 245), myristic acid (20.4 +/- 0.51, m/z 273), palmitic acid (9.8 +/- 0.47, m/z 301), linoleic acid (0.9 +/- 0.07, m/z 325), oleic acid (4.8 +/- 0.42, m/z 327) and stearic acid (2.0 +/- 0.13, m/z 329). Saponified palm kernel oil had a fatty acid profile that included caprylic acid (3.5 +/- 0.59), capric acid (4.7 +/- 0.82), lauric acid (58.6 +/- 2.3), myristic acid (20.9 +/- 1.5), palmitic acid (7.2 +/- 1.1), oleic acid (3.8 +/- 0.62) and stearic acid (1.2 +/- 0.15). Saponified palm oil gave myristic acid (0.83 +/- 0.18), palmitic acid (55.8 +/- 1.7), linoleic acid (4.2 +/- 0.51), oleic acid (34.5 +/- 1.5), stearic acid (3.8 +/- 0.26) and arachidic acid (0.80 +/- 0.22). Saponified lard showed the presence of myristic acid (1.5 +/- 0.24), palmitic acid (28.9 +/- 1.3), linoleic acid (13.7 +/- 0.67), oleic acid (38.7 +/- 1.4), stearic acid (12.8 +/- 0.64) and arachidic acid (2.4 +/- 0.35). Finally, for saponified cocoa butter, the fatty acid distribution was: palmitic acid (32.3 +/- 1.0), linoleic acid (2.6 +/- 0.35), oleic acid (34.9 +/- 1.7) and stearic acid (30.3 +/- 1.6). Quantitative gas chromatographic analysis of the corresponding methyl esters from these triacylglycerol products yielded data that were mostly in agreement with the MALDI-TOFMS data. The MALDI-TOF experiment, however, proved to be superior to the GC experiment, particularly with regard to baseline resolution of unsaturated acids. Furthermore, the ability of MALDI-TOFMS to detect low concentrations of fatty acids rendered it more sensitive than the GC methodology.  相似文献   

13.
Hepatic encephalopathy (HE) is a neuropsychiatric disorder caused by chronic and acute liver diseases. It is believed that ammonia played an important role on the pathogenesis of the disease. Herein, acid-loaded water-in-oil-in-water (W1/O/W2) multiple emulsions with over 95% encapsulation efficiency were prepared and used to absorb colonic ammonia. The study of citric acid release from W1 to W2 in bulk deionized water indicated that only 17% acid released in 8 hours, which proved the stability of the multiple emulsions and hence prevented the intestine from being irritated by acid burst release. In vitro, the W1/O/W2 emulsion could remove around 90% ammonia in 1.5 hours from either the 3 mmol/L ammonia solution or the artificial colonic fluid with 1 and 0.5 mmol/L ammonia without acidifying the artificial colonic fluid. In vivo, compared with lactulose, W1/O/W2 emulsions could efficiently reduce the blood ammonia to the similar level in the rat models with HE without increasing the water content in feces. All these results indicated a potential application of W1/O/W2 multiple emulsions for the treatment of HE.  相似文献   

14.
Cocoa butter equivalent was prepared by enzymatic acidolysis reaction of substrate consisting of refined palm olein oil and palmitic?Cstearic fatty acid mixture. The reactions were performed in a batch reactor at a temperature of 60?°C in an orbital shaker operated at 160?RPM. Different mass ratios of substrates were explored and the compositions of the five major triacylglycerol (TAG) of the structured lipids were identified and quantified using cocoa butter-certified reference material IRMM-801. The reaction resulted in production of cococa butter equivent with TAG compostion (POP 26.6 %, POS 42.1, POO 7.5, SOS 18.0 %, and SOO 5.8 %) and melting temperature between 34.7 and 39.6?°C which is close to that of the cocoa butter. The result of this research demonstrated the potential use of saturated fatty acid distillate (palmitic and stearic fatty acids) obtained from palm oil physical refining process into a value-added product.  相似文献   

15.
The fatty acid profiles of frequently consumed oils and crops cultivated in Turkey were investigated in regard to omega fatty acids. Analyses were carried out on commercially sold oils, sunflower, olive, and fish oils, and oils extracted from fatty seeds of hazelnut, walnut, olive, sunflower, poppy, sesame, and pumpkin, and butter produced in Turkey. Hazelnut and olive oils were found to be rich in omega-9 (oleic acid 18:1), walnut, poppy seed, sesame, and pumpkin seed were rich in omega-6 (linoleic acid 18:2), and butter was rich in short chain fatty acids and omega-9. Fish oil, from mackerel, was the richest in omega-3 fatty acids and fatty acid diversity. There were some alterations between commercially sold oils and oils extracted from seeds in regard to fatty acid percentages and variety.  相似文献   

16.
The development and in-house testing of a method for the detection and quantification of cocoa butter equivalents in cocoa butter and plain chocolate is described. A database consisting of the triacylglycerol profile of 74 genuine cocoa butter and 75 cocoa butter equivalent samples obtained by high-resolution capillary gas liquid chromatography was created, using a certified cocoa butter reference material (IRMM-801) for calibration purposes. Based on these data, a large number of cocoa butter/cocoa butter equivalent mixtures were arithmetically simulated. By subjecting the data set to various statistical tools, reliable models for both detection (univariate regression model) and quantification (multivariate model) were elaborated. Validation data sets consisting of a large number of samples (n = 4050 for detection, n = 1050 for quantification) were used to test the models. Excluding pure illipé fat samples from the data set, the detection limit was determined between 1 and 3% foreign fat in cocoa butter. Recalculated for a chocolate with a fat content of 30%, these figures are equal to 0.3-0.9% cocoa butter equivalent. For quantification, the average error for prediction was estimated to be 1.1% cocoa butter equivalent in cocoa butter, without prior knowledge of the materials used in the blend corresponding to 0.3% in chocolate (fat content 30%). The advantage of the approach is that by using IRMM-801 for calibration, the established mathematical decision rules can be transferred to every testing laboratory.  相似文献   

17.
The cold unspreadable consistency of butter after taking it out of the refrigerator is a rightful objection on behalf of consumers. The possibilities to improve the cold spreadability of butter are: the enrichment with low melting point triglycerides and the application of a good cream-ripening method. In our investigations milk fat fractions of different low melting points and plant oils of low melting points obtained by cold pressing and extraction have been used to change the original fatty acid composition of milk fat. The cream-ripening, the traditional method and the heat-step ripening method, which seemed to be the most effective to our earlier research, have been applied. The consistency of butter was examined by penetration measurements and its thermal characteristics by differential scanning calorimetric (DSC) method. The cold unspreadable consistency of butter can only be improved by the combination of the heat-step cream ripening and enrichment with low melting point triglycerides to get stable consistency at room temperature. The milk fat fraction of melting point below 5°C made the spreadability better but the spreadable consistency of margarine still cannot be attained. Plant oils with melting point below 0°C improved the cold spreadability of butter to a significantly higher degree than the former did. In the case of the same melting point the plant oil obtained by a cold method (pressing) was more effective. There is a close relationship between the consistency of butter and its product characteristics. From DSC curves the cold spreadability and room temperature stability of butter can be directly concluded. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

18.
Fuh MR  Hsieh CJ  Tai YL 《Talanta》1999,49(5):158-1075
This paper describes a newly developed high performance liquid chromatography/electrospray/mass spectrometry (HPLC/ES/MS) method for the determination of flunarizine (FZ) in artificial cerebrospinal fluid. The optimization for the detection of FZ in biological fluid by LC/ES/MS was investigated. The effects of solvent composition, the addition of modifier and flow rate on the detection of FZ by ES/MS were examined. The detection limit of this method (0.8 nM) proved to be much better than previously reported methods. Satisfactory accuracy (98.2–106.0%) of this newly developed method was obtained. The application of this method was demonstrated by analyzing FZ in rat microdialysis samples.  相似文献   

19.
醇脱氢制酯Cu/Zn/Al/Zr催化剂的表征   总被引:1,自引:0,他引:1  
醇脱氢制酯Cu/Zn/Al/Zr催化剂的表征温涛潘伟雄孙旭辉(清华大学化学系C1国家重点实验室,北京100084)关键词Cu/Zn/Al/Zr催化剂,乙醇,乙酸乙酯,脱氢,表征分类号O643/TQ42自Eliott等[1]报道在Cu/Zn/Al催化...  相似文献   

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