Gas chromatography/mass spectrometry (GC-MS) of the essential oil from the aerial parts of Rabdosia lophanthoides resulted in the identification of 108 compounds representing 78. 120% of the oil. Hydro-distillation of Rabdosia lophanthoides yielded a pale yellow oil. The compounds identified and their relative proportions are listed in Table 1 according to their order of elution on an HP-5 MS capillary column.

基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)是质谱分析中新型的大型仪器之一,通过开设新型大型仪器MALDI-TOF质谱的实验课程,有效地开拓学生的专业视野.针对不同的样品选择不同的基质和采取不同的检测模式,本实验以不同分子量范围的两种代表性样品聚乙二醇5000和牛血清白蛋白(66KD)为例,聚乙二醇5000选择2,5-二羟基苯甲酸作为基质;牛血清白蛋白选择芥子酸为基质,进行质谱检测.有效地让学生了解MALDI仪器的性能和应用范围,为他们今后从事科学研究工作奠定良好的基础,也让大型仪器全面支撑研究生教学,进一步提高了分析仪器的利用率.

A rapid, accurate and organic solvent saving procedure has been developed for the GC/MS determination of three phenolic antioxidants butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and butyl hydroquinone (TBHQ) in vegetable oils. The method involves two-step microextraction and a centrifugal procedure in a 2mL autosampler vial, consuming only 50mg sample and total 1mL acetonitrile. Recoveries of the phenolic antioxidants when spiked to soya bean oil, peanut oil and cereal cooking oil at 50, 200 and 250mg/kg, respectively were in the ranges 95.6–104.3% for BHT, 99.7–107.5% for BHA and 93.6–103.8% for TBHQ with the relative standard deviation (RSD) were less than 3% for their independent measurements. The developed method was repeatable and could be applied to determine trace amounts of phenolic antioxidants in vegetable oils.

A single-step large phase ratio spontaneous extraction procedure followed by gas chromatography–mass spectrometry (GC–MS) was successfully applied for the determination of caffeine in beverages. Before the GC–MS analysis, as little as 25 μL sample was spontaneously extracted with 1 mL chloroform in a 2 mL autosampler vial for 15 min. The methodology exhibited excellent linearity in the range of 0.001–20 mg L−1 with correlation coefficient of determination, r 2 > 0.9999 and a detection limit of 0.004 mg L−1. Good repeatability of extraction performance was obtained with relative standard deviation lower than 2% and the recovery of the caffeine when spiked to three different brand beverages was in the range of 98.8–102.3%. The new application-oriented single-step spontaneous extraction method was fast, efficient, and is a good alternative to routine methods for caffeine analysis in beverages.

The aim of this study was to determine the fatty acid composition of marine by-product oils.The effect of the oils on the obesity mice was also studied.Oils were separated from two different marine by-products(mackerel's head and squid's entrails) with Folch method.Fatty acid composition was analyzed by GC-MS after the oils were methyl esterified.The oils were administered respectively to mice fed with high-fat diet by gavage,and the effects of these were studied according to several indexes,such as growth and development condition,bodyweight growth rate,organ indexes and body fat accumulation rate of the mice.The results showed that both of the oils detected several unsaturated fatty acids,including oleic acid,eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA) et al.Both of the oils were effective in lowering bodyweight,organ indexes and body fat of mice.Our study showed that proper process technology could wtilize the compounds in marine by-products wltimately.

A rapid, accurate and organic solvent saving method has been developed for the ultraviolet spectrophotometric (UV) determination of caffeine in beverages. The centrifugal extraction procedure with large phase ratio was applied to sample micropreparation prior to instrumental analysis. The method involves the mixing of 100 mu L sample with 2 mL chloroform and a 3-min centrifugal extraction procedure in a centrifugal tube. The clear solution obtained was directly determined by UV detection at wavelength of 278 nm. The manipulation was simple and repeatable, and the relative standard deviation of the method was less than 3% for the independent measurement. When added different concentration of standard caffeine solution to three brand beverages, the recovery of the caffeine was in the range of 96.6% - 106.1%. A linear calibration curve was obtained with caffeine concentration ranging from 0.50 - 30 mg/L, giving the correlation coefficient as 0.9999. The method provides a 0.001 mg/L detection limit of caffeine. The developed method was applied to determine the caffeine content in commercial beverages with good results.

Solid-phase microextraction (SPME) in combination with gas chromatography-mass spectrometry (GC-MS) was applied to study the impurities in industrial caprolactam produced from toluene. Various nitriles, lactones, amides, and alcohols were detected to be the main impurities in caprolactam products. Trace amounts of heterocyclic compounds, which had great effects on the quality of caprolactam, were also successfully detected. Those were pyrrole, 2-ethyl-3-methyl pyrazine, 5,6,7,8-tetrahydroquinoxaline, quinoxaline, 2,3-dimethyl quinoxaline, 2-pyridinamide, etc. The effects of some impurities on caprolactam quality and the polymerization of caprolactam as well as the possible origin of the main impurities were also discussed. This could be of great importance to the industrial purity control of caprolactarn. (c) 2006 Wiley Periodicals, Inc.

A simple, quick and organic solvent saving procedure has been developed for the GC/MS determination of caffeine in beverages. The procedure involves the mixing of 25μL sample with 1mL ethyl acetate, and a following simple desiccation procedure in a 1.5mL autosampler vial. A linear calibration curve was generated with caffeine concentration ranging from 0.005mg/L to 30.0mg/L. The procedure developed provides a 0.001mg/L detection limit of caffeine in the final solution by injection of 1μL solution and the relative standard deviation (RSD) was less than 2% for independent measurement. The total amount of organic solvent used for individual detection is 1mL of nontoxic ethyl acetate. The developed method was repeatable and could be applied to determine trace amounts of caffeine in popular commercial beverages.

This research examined the typical flavor compounds in the commonest type of Khat called Harari Khat grown in the region of Ethiopia. Twenty-eight compounds, which includes 1,2-Propanedione, 1-Phenyl, Hexanol, Hexanal com-pounds, Limonene, Benzaldehyde with other flavors, were extracted by polydimethylsiloxane at room temperature for 30 min from Khat samples, and identified by solid-phase microextraction-gas chromatography-mass spectrometry (SPME- GC-MS). This method needs no organic solvents and required minimal sample.

卡氏乌头Aconitum carmichaeli Debx.为毛茛科乌头属植物,生于山地、丘陵地、林缘,分布于长江中下游各省,北至秦岭,南达广西北部.乌头为炮制后的膨胀大主根.生乌头酊外用能刺激皮肤,用作止痛剂.附子为其较大的侧根,有回阳救逆,补火助阳,逐风寒湿邪之功效,用于亡阳虚脱,肢冷脉微,阳痿、宫冷、心腹冷痛,虚寒吐泻,阴寒水肿,阳虚外感,寒湿痹痛.草乌为其干燥母根,有祛风除湿,温经止痛之效,用于风寒痹痛,关节疼痛,心腹冷痛,麻醉止痛.

A method for analyzing the composition of triacylglycerols in butterfat was developed by high temperature gas chromatography-electron impact mass spectrometry with HP-5 MS 30 m×0.25 mm×0.25 μm capillary column. According to the analysis of GC-MS, 108 triacylglycerols were identified. The main triacylglycerols include butyrodipalmitin, dipalmitocaprin, dipalmitolaurin, dipalmitomyristin, butyropalmito-olein and butyropalmitostearin with relative contents of 8.2%, 7.9%, 7.7%, 6.9%, 6.2% and 5.9%, respectively.

The essential oil from the aerial parts of Rabdosia macrocalyx was extracted by hydrodistillation method. The oil obtained was analyzed by gas chromatography/mass spectrometry (GC-MS). More than 116 peaks were separated and sixty compounds representing 75.77% of the oil were identified.

Objective: To develop a method for the determination of ligustilide in Angelica sinensis essential oil. Methods: GC - MS method using American HP 5973 GC - MS apparatus, HP - 5 (30 m ×0. 25 mm × 0. 25 μm) capillary column, HP chemical station, NIST MS library and HP7683 autosampler. The carrie gas is heli-um. Column temperature rises by programming. The injector temperature is 250℃ and the detector temperature is 280℃. Ligustilide was determined by means of GC - MS with selected ion and qualifier ion monitoring. Results: The Standard curve is linear for ligustilide within 1. 34 ng -1. 34 pg and the sensitivity is 0. 1 ng · mL-1 ( S/N = 10). The average recovery is 98. 9% and RSD is 2. 2% . Conclusion: The results show this method is sensitive, rapid and accurate.

The essential oil from the aerial parts of Rabdosia macrocalyx was extracted by hydrodistillation method. The oil obtained was analyzed by gas chromatography/mass spectrometry ( GC-MS). More than 116 peaks were separated and sixty compounds representing 75.77% of the oil were identified.

1 引言 油脂是人类的主要食品之一,其主要成分是脂肪酸甘油三酯,它参与人体正常生理代谢.油脂香气成分是其微量成分,含量一般在油脂总量的1%以下,却构成其各自特征香气.奶油、玉米油、牛油等均有较详细的报道.本文以GC/MS分析猪油香气成分,70种成分被确定.

OBJECTIVE To make a solid form of Angelica Sinensis essential oil by preparing its inclusion compound with beta-cyclodextrin and evaluate the inclusion rate, dissolution rate and liberating rate of this complex. METHOD GC-MS, X-ray diffraction and thin-layer chromatography were applied to characterize the essential oil and the inclusion compound. RESULT The inclusion compound was shown to form a new phase by X-ray diffraction analysis. GC-MS and TLC check-up corroborated the composition of the free oil and the inclusion oil remaining the same. CONCLUSION The results showed Angelica Sinensis essential oil was more stable with beta-cyclodextrin inclusion. The preparation of this inclusion compound has advantages in limited amount, long time effect, easily preserved and convenient administration as a new dosage form.

A high temperature gas chromatography(GC)-electron impact (EI) mass spectrometric (MS) method was developed for analyzing the composition of triacylglycerols in coconut oil. Portions (1muL) of coconut oil solution (1 g/L in hexane), with a split ratio of 1:50, were analysed on a column (30 m x 0.25 mm i.d.) coated with HP5MS (0.25 mum), with He as carrier gas, temperature programing from 300degreesC (hold for 3 min) to 350degreesC at 2degreesC/min and EIMS detection in scan mode (m/z = 30 similar to 800) for identification. According to the analysis of GC/MS, 36 triacylglycerols were identified. The main triacylglycerols were octoyl dilauroyl glycerol and didecoyl lauroylglycerol (12.48%, area percent), decoyl dilauroylglycerol (7.69%), octoyl lauroyl myristoylglycerol (10.81%), trilaurin and decoyl lauroyl myristoylglycerol (15.34%), octoyl lauroyl palmitoylglycerol (6.51%), dilauroyl myristoylglycerol and decoyl lauroyl palmitoylglycerol (17.01%), dilauroyl palmitoylglycerol and decoyl lauroyl stearoylglycerol (11.09%), dilauroyl stearoylglycerol and lauroyl myristoyl palmitoylglycerol (5.35%).

葡萄酒是风行世界的饮料酒。其酒精度低且含有较多的果酸，是一种具有美容作用的酒饮料。近年来中国葡萄酒工业发展较快，但由于葡萄酒水分多、糖度高，呈味物质复杂，且葡萄产地，气候、生产工艺、储存条件均会影响其风味，给生产控制带来了一些困难，本文以GC/MS研究中国干红葡萄酒香味成分，48种成分被确定。