GC-MS分析法在人参有机氯农药残留检测中的应用

以丙酮－饱和氯化钠溶液－石油醚的一步法提取分离技术制备样品溶液，采用ＧＣ－ＭＳ分析方法对人参中有机氯农药残留进行了测定。加标人参样品的测定结果表明：两个水平加标回收率：０．１０ｍｇ／ｋｇ添加水平时，除ＰＣＮＢ平均回收率为５８．３％，其它组分的平均回收率为７６．０％～９０．１％，相对标准差为９．３％～１５．０％；０．０５０ｍｇ／ｋｇ添加水平时，平均回收率为６２．３％～８７．２％，相对标准差为６．０％～２２．５％。应用本方法测定人参中有机氯农药残留，基本上满足了灵敏、快速。

美人蕉叶挥发油的GC-MS分析

目的:采用水蒸气蒸馏法提取美人蕉叶的挥发油。方法:运用气质谱联用(GC-MS)技术研究海南美人蕉叶的挥发油化学成分。并采用峰面积归一化法确定各成分的相对百分含量。结果:共鉴定出45种成分,占总离子流出峰面积的25.38%。美人蕉叶挥发油主要有1,1-二乙氧基乙烷(5.56%),二甲基氰膦(4.53%)和邻苯二甲酸单(2-乙基己基)酯(3.61%)。结论:该研究为美人蕉的进一步开发和利用提供基础研究数据。

Chemical fingerprinting of Su-He-Xiang-Wan and attribution of major characteristic peaks for its quality control by GC-MS

A simple and facile gas chromatography-mass spectrometer （GC-MS） fingerprint of Su-He-Xiang-Wan （SHXW） was developed, the similarity analysis was conducted, and attribution of the major characteristic peaks was identified for SHXW quality control. GC-MS analysis was performed on a QP2010 instrument （Shimadzu, Japan） equipped with a capillary column of RTX-5MS. The column temperature was initiated at 50℃, held for 5 min, increased at the rate of 3 ℃/min to 120 ℃, held for 2 min, and then increased at the rate of 4 ℃/min to 220℃, held for 10 min. Helium carrier gas was used at a constant flow rate of 1.3 mL/min. Mass conditions were ionization voltage, 70 eV; injector temperature, 250℃; ion source temperature, 250 ℃; splitting ratio, 30：1; full scan mode in the 40-500 Da mass ranges with rate of 0.2 s per scan. Attribution of the major characteristic peaks was identified for SHXW by comparing the chemical standards, references of Chinese herbal medicines and the negative controls of prescription samples （NC） of SHXW. With the help of the temperature-programmed retention indices （PTRIs） used together with mass spectra and chemical standards, 25 major characteristic peaks have been identified. Nine volatile medicinal materials were identified in the prescription of SHXW by attributing to the 27 major characteristic peaks. The results demonstrate that the proposed method is a powerful approach to quality control of complex herbal medicines.

Identification of Volatile Compounds in Codfish(Gadus) by a Combination of Two Extraction Methods Coupled with GC-MS Analysis

Codfish is a kind of abyssal fish species with a great value in food industry. However, the flavor of codfish, especially the unpleasant odor, has caused serious problems in its processing. To accurately identify the volatile compounds in codfish, a combination of solid phase micro-extraction(SPME) method and simultaneous distillation extraction(SDE) method was used to extract the volatiles. Gas chromatography-mass spectrometry(GC-MS) along with Kovats indices(KI) and authentic standard compounds were used to identify the volatiles. The results showed that a total of 86 volatile compounds were identified in codfish, of them 24 were extracted by SDE, 69 compounds by SPME, and 10 compounds by both SDE and SPME. Seventy volatile compounds were found to have specific odors, of them 7 typical compounds contributed significantly to the flavor of codfish. Alcohols(i.e.,(E)-2-penten-1-ol and 2-octanol), esters(i.e., ethyl butyrate and methyl geranate), aldehydes(i.e., 2-dodecenal and pentadecanal) contributed the most to fresh flavor while nitrogen compounds, sulphur compounds, furans, as well as some ketones(i.e., 2-hydroxy-3-pentanone) brought unpleasant odor, such as fishy and earthy odor. It was indicated that the combination of multiple extraction methods and GC-MS analysis can enhance the accuracy of identification, and provide a reference for the further study on flavor of aquatic products.

柠檬油主要成分分析及应用研究

采用气相色谱-质谱联用技术检测并分析了柠檬油中的挥发性成分,共分离出50种挥发性成分,主要成分是柠檬烯(83.70%)、柠檬醛(4.56%)、β-蒎烯(1.83%)、芳樟醇(1.80%)、β-月桂烯(1.48%),萜类及其衍生物的质量分数占柠檬油挥发性成分质量分数的95%以上,这些成分构成了柠檬油的主体香韵。根据感官评价,柠檬油具有增进卷烟果香、清甜香,减少刺激性,提升卷烟吸食品质的作用。

3种桦木属植物木醋液成分分析

为深度开发桦木属植物资源,以白桦、枫桦和油桦为原料,采用热解法收集额定功率2000 W条件下的热解液,通过精制热解液以获得3种醋液。应用气相色谱-质谱联用(GC-MS)技术对3种木醋液的成分和各成分相对百分含量进行测定与分析。最终检测出白桦、枫桦和油桦3种木醋液中含有机物质种类分别为46、62、43种,主要成分均为酚类、醛类、酮类和酸类,白桦、枫桦和油桦木醋液中酚类物质含量最高,其种类和相对含量由大到小依次为:12种38.30%、10种25.87%、10种23.06%。结果显示,不同品种桦树木醋液成分具有显著性差异。研究结论可以为桦木属植物资源的整合与利用提供参考依据。

发酵小麦粉加热过程中挥发性成分分析

热加工是面食制品风味形成的主要过程。该文以发酵小麦粉为主要原料应用气质联用技术探究了其在热加工过程中挥发性物质的形成规律。结果表明,发酵小麦粉在加热过程中,共发现88种挥发性化合物,分别为醛类19种、醇类15种、酮类11种、含苯衍生物15种、呋喃类11种、酸酯类10种和杂环类化合物7种。当加热温度高于110℃时,挥发性物质的种类开始明显增加,温度达到120℃时,各挥发性物质的构成和含量变化最为显著。该文测定了各挥发性成分的形成温度,在60~100℃时,挥发性风味成分主要由C6~C10挥发性醛类和醇类组成。而在超过100℃,特别是在120℃时,形成了许多长碳链的醛类和醇类、呋喃类、酸类、酯类和含氮化合物。

超声-微波协同萃取分离、气相色谱-质谱联用测定土壤中多环芳烃

建立了常温常压条件下超声-微波协同萃取分离、气相色谱-质谱法(GC-MS)测定土壤样品中微量多环芳烃的方法,结果表明:在土壤含水量和无机盐质量分数分别为10%和6%时,以正已烷-二氯甲烷(1+1)混合溶液40 mL作萃取溶剂,采用100 W微波辐射功率(超声振动功率固定为50 W)萃取9 min,模拟土壤样品中多环芳烃平均回收率可达86.9%,其相对标准偏差为3.6%;通过与索氏抽提、高压密闭微波和开放式微波、直接超声波和间接超声波等萃取方法相比,证明此方法具有样品容量大、萃取时间短、萃取效率高、重现性好等优点。

中药透骨草的化学成分及药理活性探究

目的分析中药透骨草的化学成分及药理活性。方法于2017年8月—2018年4月在南通大学分析测试中心选择最优提取条件对透骨草进行提取,使用萃取法对中药透骨草的提取物进行萃取,使用GC-MS分析法对萃取导致的石油醚层内的挥发油的详细成分通过毛细管柱的色谱进行详细分析,鉴定中药透骨草的化学成分及其药理活性。结果本实验检测发现,共检测出52种化学物质,这52种化学物质中以棕桐酸乙酯和棕桐酸的含量最多,两者占29.03%,其中相对含量>10.0%的化学物质有棕桐酸、棕桐酸乙酯,相对含量在4.0%~10.0%的化学物质有1-甲氧基丁烷、(7、65、7A)圆氢2苯呋喃酮。在所有分类中酯类化合物的占比最高,达到了24.65%,其次为酸类化合物,占比为19.91%。结论透骨草相对含量最高的物质是棕桐酸乙酯和棕桐酸,其作为药物发挥作用的物质很可能是酯类化合物、酸类化合物中的一种或几种化合物。

亚临界丁烷萃取丁香挥发油的工艺优化

以丁香为材料,对亚临界丁烷萃取丁香挥发油成分的工艺进行了优化,并采用GC-MS法对比分析了超临界CO_2萃取法与亚临界丁烷萃取法获得的丁香挥发油成分。结果表明:亚临界丁烷萃取丁香挥发油的最佳工艺条件为萃取时间60 min,萃取温度40℃,萃取次数3次,在此条件下丁香挥发油的得率为18.65%,与超临界CO_2萃取(SCF)得到的丁香挥发油相比得率相当,主要成分及含量差异小。这表明亚临界丁烷适用于丁香挥发油的高效萃取。

New advances in coal structure model

Although human beings have come to understand and utilize coal for a very long history, no theoretical breakthrough in the study of coal structure has been made, which still needs continuous efforts of coal chemical workers. Based on the viewpoint of ‘vague/clear', the species classification and accurate analysis on coal were conducted by using the natural clustering all-component separation method. A more systematic and detailed coal embedded structure model theory which is suitable for coal of all ranks was developed from the previous one and a more complete theoretical system about the component and structure of coal was constructed. The whole establishment process of the theory was summarized and some of the main support data and analysis test results, including TEM, AFM, FTIR, GC/MS, MALDI/TOF/MS, DART/MSD, fractal analysis and so on were provided. The coal embedded structure theory fully considers both the identity and the particularity of all-rank coal, reflects the coal component and structure in the full range of coal rank, solves the systematic cognitive problem of coal component and structure on macro and micro level, and provides a valuable and meaningful theoretical approach for the coal processing and conversion technology.

Component Analysis of Volatile Oil of Garlic from Different Districts and Assay of Allicin Content

[ Objective] The aim was to study the chemical component of volatile oil of garlic in different districts. [ Method] GC-MS was used to an- alyze the composition of the garlic volatile oil in Guiyang, Guizhou Majiang, Shandong, Yunnan and Chongqing and the HPLC method was used to assay the content of gadicin. [ Result]Gadicin in different essential oil had the highest content but varied a lot. The sampling amount of garlicin be- tween 0.562 and 2.810 μg was in a good linear relation （R =0.999 2, n = 5 ） with peak area, the average recovery rate was 99.39, RSD = 1.76%. [ Conclusion] GC-MS can be used to analysis the composition of essential oil quickly and effectively. The liquid chromatographic analysis of garlicin was simple, reliable and reproducible. The study provided the theoretical basis for selecting garlic in gadic flavor oil production and improving quality of gadicin oil.

Preparation and Evaluation of Microcapsule Containing Volatile Oil of Herba Schizonepetae by Emulsion Solvent Diffusion Method

Microcapsules of volatile oil containing Herba Schizonepetae(VOHS) were prepared by emulsion solvent diffusion method to improve the drug loading and reduce the amount of pharmaceutical excipients.Orthogonal assay was applied to optimize the preparation condition of microcapsulation,and the results illustrated that the ratio of ethyl cellulose(EC) to VOHS influenced the property of VOHS microcapsule significantly.GC-MS analysis indicated that some volatile components with low concentration in VOHS were lost after microencapsulation.The microcapsules prepared with optimum condition had good fluidity,and the holes on the surface of the microcapsules contributed to the release of VOHS.The particles of the microcapsule conformed to a normal distribution with the diameter of 45—220 μm.In the simulated intestinal fluid containing 0.2% sodium dodecyl sulfate,pulegone in VOHS microcapsule showed a certain degree of slow release.Compared with β-cyclodextrin method,the microencapsulation used in the present work could reduce the amount of excipients and increase the drug loading.It was beneficial to reduce the dose of Chinese medicines containing volatile oils.

Study on the Antioxidant Component of Fermented Rice Bran by Bacillus Natto

Each component of rice bran fermentation(RBF)of Bacillus natto was extracted and its antioxidant activity was tested.By dint of thin layer chromatography,the antioxidant components were separated.The sample isolated from TLC for ethyl acetate phase and ether phase was analyzed by GC-MS.Results indicated that the antioxidant activity of large components in rice bran fermentation was low.The constituents of extracted phase had antioxidant activity apart from the petroleum ether phase.The constituents of ethyl acetate phase and Ether phase had best antioxidant activity,163 and 168 kU/g,respectively.The main composition of ethyl acetate phase was allyl group methyl-thioether and the main composition of ether phase included 3,5-dimethyl phenol,2,4-dipl-tert-Butyl and Fluazifop.

Study on the basic nitrogen compounds from coal-derived oil

The distillation range analysis and elemental analysis of fractioned direct liquefied oil were conducted. Each fraction of liquefied oil contains some nitrogen compounds. Using the acid extraction method and gas chromatography/mass spectrometry （GC-MS）, the basic nitrogen compounds have been separated and identified. Compared with the nitrogen content of the liquefied oil before and after separation, the basic nitrogen compounds account for more than half of all nitrogen compounds. The basic nitrogen compounds in the light liquefied oil are easily separated, and contain more types of basic nitrogen compounds. The results also show that there are many basic nitrogen compounds in liquefied oil, such as pyrrole, aniline, pyridine, quinoline and so on. However, there are fewer other types of basic nitrogen compounds.