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采用超临界CO2萃取蝼蛄总脂肪酸,对影响萃取效果的各个因素应用正交设计试验,优化了各萃取参数。各个因素的影响顺序为:压力〉温度〉时间〉流量。萃取的优化条件为压力35MPa,温度50℃,时间1h,流量45kg/h。运用该萃取条件改善了萃取物的物理性状,脂肪酸的纯度提高,总脂肪酸的含量可达83.29%;而采用常规的有机溶剂提取法,脂肪酸的纯度仅为60%左右。甲酯化采用气相色谱-质谱分析技术对其中的16个成分进行了鉴定,并测定了相对含量,其中主要有油酸甲酯(30.40%)、十六烷酸甲酯(14.19%)、9,12-十八碳二烯酸甲酯(11.99%)、油酸乙酯(11.75%)、9-十六碳烯酸甲酯(7.77%)、十六烷酸乙酯(5.97%)、9,12-十八碳二烯酸乙酯(4.53%)及9-十六碳烯酸乙酯(2.87%)等。 相似文献
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超临界萃取蝼蛄脂肪酸成分及其气相色谱-质谱分析 总被引:1,自引:0,他引:1
采用超临界CO2萃取蝼蛄总脂肪酸,对影响萃取效果的各个因素应用正交设计试验,优化了各萃取参数.各个因素的影响顺序为压力>温度>时间>流量.萃取的优化条件为压力35 MPa,温度50℃,时间1 h,流量45 kg/h.运用该萃取条件改善了萃取物的物理性状,脂肪酸的纯度提高,总脂肪酸的含量可达83.29%;而采用常规的有机溶剂提取法,脂肪酸的纯度仅为60%左右.甲酯化采用气相色谱-质谱分析技术对其中的16个成分进行了鉴定,并测定了相对含量,其中主要有油酸甲酯(30.40%)、十六烷酸甲酯(14.19%)、9,12-十八碳二烯酸甲酯(11.99%)、油酸乙酯(11.75%)、9-十六碳烯酸甲酯(7.77%)、十六烷酸乙酯(5.97%)、9,12-十八碳二烯酸乙酯(4.53%)及9-十六碳烯酸乙酯(2.87%)等. 相似文献
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自制氨基哌嗪功能化丹磺酰氯(DNS-CL)荧光衍生试剂(DNS-Pi-NH_(2)),并用其衍生化小球藻中碳原子数为10~20的典型脂肪酸[十二烷酸、十四烷酸、顺-9,12-十八(碳)烯酸、顺-7,10,13-十六(碳)烯酸、十六烷酸、顺-9-十八(碳)烯酸、十八烷酸、二十烷酸],用高效液相色谱法(HPLC)测定8种脂肪酸的含量。将小球藻脂肪酸甲酯样品用含氢氧化钾的乙醇溶液于79℃皂化60 min,滴加盐酸溶液,直至酚酞指示剂由红色变为无色。蒸发除去乙醇,所得固体经水清洗、离心、振荡、过滤,即制得小球藻脂肪酸样品。以DNS-CL和N-(2-氨基乙基)哌嗪为原料制备DNS-Pi-NH_(2),并用红外光谱、核磁共振碳谱、质谱对其结构进行表征。取制备好的DNS-Pi-NH_(2)、二丙基二硫醚、三苯基磷的乙腈溶液和1.0 mg小球藻脂肪酸样品在室温下振荡衍生10 min,所得溶液用90%(体积分数,下同)乙腈溶液稀释后,用HPLC测定其中脂肪酸衍生物的含量。以Eclipse XDB C_(8)色谱柱为固定相,以90%乙腈溶液为流动相进行等度洗脱,分离得到的目标物用荧光检测器检测。结果显示:8种脂肪酸衍生物在30 min内可实现完全分离;各脂肪酸的浓度在2.0×10^(-10)~2.0×10^(-4)mol·L^(-1)内与其对应的峰面积呈线性关系,检出限(3s/k)为21~65 pmol·L^(-1);对微藻培养液样品进行加标回收试验,所得回收率为95.3%~102%,测定值的相对标准偏差(n=5)为1.7%~2.6%;方法用于小球藻脂肪酸甲酯样品的分析,检出了十六烷酸、顺-9,12-十八(碳)烯酸、顺-7,10,13-十六(碳)烯酸、顺-9-十八(碳)烯酸,检出量分别为3.08,0.64,0.83,2.57 mg·g^(-1)。 相似文献
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月光花素甲(Calonyctin A)是从月光花[Calonyction aculeatum(L.)House]叶中分离获得的一种高活性的植物生长抑制剂,经IR、NMR及MS分析证明,它是药喇叭酸乙酯的五聚糖甙,其甙元为dl-11-羟基十六烷酸乙酯。 Tomecko和Adams及Davies和Adams曾合成11-羟基十六烷酸甲酯。我们采用如下改进方法合成dl-11-羟基十六烷酸乙酯。 相似文献
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蓝布正挥发油化学成分的GC-MS分析 总被引:7,自引:0,他引:7
研究贵州产蓝布正(Herba Gei)挥发油的化学成分,采用水蒸气蒸馏法提取蓝布正挥发性成分,用气相色谱-质谱进行分离测定,结合计算机检索技术对分离的化合物进行鉴定,应用色谱峰面积归一化法测定各成分的相对含量;水蒸气蒸馏提取物得率是0.10%,共分离出103种成分,鉴定出40个化学成分,其主要成分为脂肪酸及其甲酯类化合物、萜烯类及其含氧衍生物等,主要有棕榈酸(13.2%)、11,14,17-二十碳三烯酸甲酯(10.4%)、亚油酸(8.6%)、石竹烯氧化物(3.9%)、丁子香酚(3.4%)和反式-植醇(3.2%)等。 相似文献
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毛细管气相色谱和气相色谱/质谱法分析五灵脂挥发性成分 总被引:2,自引:0,他引:2
利用同时蒸馏萃取法(SDE)提取五灵中的挥发性组分。SE-54柱和PEG-20M柱上用气相色谱-质谱法分别检出122个和96个峰。其中有51种峰质谱检索结果相同,它们占总峰面积的56.3%。进一步用程序升温保留指数确认了其中33种化合物,占总峰面积的35.7%。含量较高的组分有:十二酸(7.00%),α-雪松醇(4.41%),四甲基吡嗪(4.10%),寸上酸(3.37%),1-(3-甲苯基)乙酮(2.53%),苯甲醛(2.42%),2-甲氧基苯酚(2.11%)。从化合物的种类来看,主要为醇类(10种),酮类(8种),醛类(8种),醛类(6种)、烯类(5种)、酸类(4种),酚类(4种)。 相似文献
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Identification of aroma active compounds in orange essence oil using gas chromatography-olfactometry and gas chromatography-mass spectrometry 总被引:3,自引:0,他引:3
Using GC-MS and GC-flame ionization detection (FID)/olfactometry, 95 volatile components were detected in orange essence oil, of which 55 were aroma active. In terms of FID peak area the most abundant compounds were: limonene, 94.5%; myrcene, 1%; valencene, 0.8%; linalool, 0.7%, and octanal, decanal, and ethyl butyrate, 0.3% each. One hundred percent of the aroma activity was generated by slightly more than 4% of the total volatiles. The most intense aromas were produced by octanal, wine lactone, linalool, decanal, beta-ionone, citronellal, and beta-sinensal. Potent aroma components reported for the first time in orange essence oil include: E-2-octenal, 1-octen-3-ol, Z-4-decenal, E,E-2,4-nonadienal, guaiacol, gamma-octalactone, and m-cresol. Over 20 compounds were identified for the first time in orange essence oil using MS, however, most did not exhibit aroma activity. 相似文献
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蛇龙珠干红葡萄酒香气成分的GC-MS分析 总被引:47,自引:0,他引:47
研究宁夏贺兰山东麓地区蛇龙珠(Cabemet Gemischt)干红葡萄酒香气的化学成分,采用溶液萃取法提取蛇龙珠干红葡萄酒中的香气成分;用气相色谱一质谱进行分离测定,结合计算机检索技术对分离化合物进行鉴定,应用TIC峰面积归一法测定各成分的相对含量;分离出32个峰,鉴定出29个香气化学成分,共占其色谱流出组分总量的98.06%;其中相对含量以3-甲基丁醇(47.97%)、丁二酸二乙酯(16.49%)、苯乙醇(10.33%)、2-羟基丙酸乙酯(6.41%)、2-甲基丙醇(3.51%)、二氢化-2[3氢]-呋喃酮(2.07%)、2,3-丁二醇(1.93%)、四氢化2-甲基噻吩(1.68%)、乙酸乙酯(1.21%)、己醇(0.95%)等成分为主。 相似文献
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Bahar Bilgin Sokmen Belma Hasdemir Ayse Yusufoglu Refiye Yanardag 《Applied biochemistry and biotechnology》2014,172(3):1358-1364
A series of some 3-,6-,7-,9-,12- monohydroxy tetradecanoic acids were evaluated for their antiurease, antielastase and antioxidant activities for the first time in this study. All the test compounds exhibited antioxidant, antielastase and antiurease activities. The relationship between the position of the hydroxy group and the enzyme inhibition effect is studied in this work. The mentioned biological activities are depending on the position of hydroxy group of tetradecanoic acid isomers. The results obtained in this work are indicating that 3-,6-,7-,9-,12-monohydroxy tetradecanoic acid isomers can be used in agriculture, pharmacy and cosmetic industries due to their excellent antielastase, antiurease and antioxidant activities. 相似文献
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Analysis of ethyl glucuronide and ethyl sulfate using aqueous normal‐phase chromatography with mass spectrometry
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The use of aqueous normal‐phase chromatography is explored as a possible format for the analysis of the forensically significant compounds ethyl glucuronide and ethyl sulfate. Standard solutions of the two compounds are used to verify the retention capabilities of two stationary phases (diamond hydride and undecanoic acid). These results are then compared to data obtained on hair extracts to determine if any matrix effects exist with respect to both retention and peak shape. The undecanoic stationary phase is used for the establishment of calibration curves for quantitative analysis. These curves are utilized to determine the concentration of ethyl glucuronide in several hair samples tested. 相似文献
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梨圆蚧性信息素3,7-二甲基-2,7-辛二烯-1-醇丙酸酯的合成 总被引:3,自引:1,他引:2
Gieselmann等鉴定出梨圆蚧性信息素的主要组分为(Z)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(1a)及相应的E-体(1b)。 相似文献
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Gaowa Jin Lijie Liu Yuanliu Yang Yan Zhang Ping Zhao Dongping Yu Yongzheng Zhou Zhimou Guo Hui Wang Xinmiao Liang 《Journal of separation science》2022,45(11):1866-1873
The availability of various high-purity unsaturated fatty acids has a wide range of needs due to their different activities. The nonlinear preparative chromatography behavior and principle for purification of palmitoleic acid with octadecyl bonded stationary phases were studied. The peak broadening and the concentration distribution of the target compounds were used to compare different C18 stationary phases. In preparative liquid chromatography, the C18 stationary phases with low, medium, and high bonding density showed different peak broadening and concentration distribution results. Medium bonding density C18 was suitable for the purification of ethyl palmitoleic acid. The forward broadening was much greater than the backward broadening on medium bonding density C18 column. And the highest concentration distribution of impurities and the main peak was not crossed in this column. Due to the low content of crude ethyl palmitoleic acid sample, a two-step purified method yields an oily product with purity of 96.57% in the GC method. This method would be universal and extensible for constructing purification method for other unsaturated fatty acids. 相似文献
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鸽子粪挥发性成分的毛细管气相色谱分析 总被引:2,自引:0,他引:2
利用同时蒸馏萃取法(SDE)提取了有治疗痔疮效果的鸽子粪中的挥发性成分。用毛细管GC/MS/DS联用法分离鉴定了47种组分,占总峰面积的71.59%,再用保留指数和标样进一步确证了其中39种化合物,占总峰面积的57.15%,其中含量较高的组分是十六碳酸(9.03%)、乙酸乙酯(6.85%)、乙醇(4.03%)、1-乙氧基-2-甲基丙烷(3.87%)。从化合物的种类看,主要为醇类(4个)、醛类(11个)、酮类(4个)、酸类(8个)、酯类(5个)和酚类(2个),它们共占总峰面积的43.68%。 相似文献
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Several packing materials were evaluated for their sampling performance with a cold programmed temperature vaporizing injector operated in the solvent split (solvent elimination) mode. Evaluations were made by comparing accuracy and precision of the data for mixtures of n-alkanes, ethyl esters, n-alcohols, and carboxylic acids covering polarity and volatility ranges typical of compounds present in food samples. Tenax exhibits the most desirable retention characteristics. Careful selection of the experimental conditions lowers losses of volatile compounds by co-evaporation with the solvent and allows a reliably quantitative analysis. Coefficients of variation of relative (normalized) peak areas and absolute peak area ratios of each compound to the standard are generally less than 2%. 相似文献