GC–MS法分析茵陈挥发油成分

采用水蒸气蒸馏法提取茵陈中挥发性成分挥发油,用气相色谱–质谱联用技术(GC–MS)对茵陈挥发油成分进行分析鉴定,并采用峰面积归一化法测定其相对含量。共检出52种挥发性成分,鉴定了其中31种主要挥发性成分,含量较高的组分为石竹素(15.27%)、(–)-斯巴醇(6.64%)、石竹烯(4.89%)等。GC–MS法适用于茵陈挥发性成分的定性分析,具有灵敏度高、分析速度快的特点。     

三种丁香花精油的挥发性成分比较分析

为了解紫丁香、白丁香和红丁香花蕾精油样品挥发性成分的差异,采用气相色谱-质谱联用技术（GC-MS）分析了三种丁香花精油样品的挥发性成分,并对三者的挥发性成分进行了主成分分析和聚类分析。结果从紫丁香、白丁香和红丁香精油中分别解析出46、64和56种挥发性物质,包括烷烃类、酯类、醇类、酮类、烯烃类、酚类、有机酸等,其中共有的挥发性成分为9种。三种丁香花精油样品的挥发性成分比较分析显示,酯类是含量最高的挥发性成分,其次是烷烃类,并且这两类物质在不同品种的丁香花精油中含量不同。统计分析结果表明三种样品的挥发性成分之间没有明显差别。本研究为增加丁香花精油的应用范围提供了理论依据。     

固相微萃取-气相色谱-质谱法分析火龙果果肉中挥发性成分

火龙果不仅具有保健功能,还具有降血压、降血脂、润肺、解毒、养颜等药用功效,被称为21世纪保健食品和果品珍品。目前关于火龙果的研究主要集中在茎、花、种籽、果实色素等方面[1-6],而对其果肉中挥发性成分的研究未见报道,但果肉中挥发性成分对于水果的保鲜具有重要的作用[7]。近年来,固相微萃取(SPME)技术在水果挥发性成分分析方面已得到了一定的应用[8-9],SPME具     

静态顶空-气相色谱法在烟草行业中的应用进展

综述了静态顶空-气相色谱法的发展现状、原理、技术类型、影响因素及其在烟草行业中的应用。主要介绍了在烟草挥发性成分、卷烟烟气挥发性成分、烟用添加剂挥发性成分及烟用辅料挥发性成分等方面的测定,并简要介绍了其应用前景(引用文献56篇)。     

微波蒸馏-固相微萃取-气相色谱-质谱-嗅觉检测器联用分析鳙鱼鱼肉中的挥发性成分

用微波蒸馏(MD)-固相微萃取装置(SPME)提取鳙鱼鱼肉中的挥发性成分,利用气相色谱-质谱联用仪(GC-MS)对气味化合物成分进行了定性分析,同时利用嗅觉检测器鉴别了部分挥发性物质的气味特征。实验中优化了MD的操作条件(加热功率、加热时间及载气流速等)、SPME参数(萃取头种类、萃取温度、萃取时间、无机盐离子浓度及搅拌速率等)。通过NIST 02质谱数据库检索共定性确定出鳙鱼鱼肉挥发性成分中的53种化合物,其中主要为 C6~C9 的羰基化合物和挥发性醇类。经过嗅觉检测器分析,这些成分分别具有青草味、鱼腥味、泥土味等气味特征,其协同作用构成了鳙鱼鱼肉特殊的鱼腥味、泥腥味。该方法可用于水产品中挥发性成分的分析,并可为不良风味化合物的定量研究提供参考。     

GC-MS法分析姜花属四种植物的挥发性成分

分析姜花属白姜花、黄姜花、小花姜花、圆瓣姜花这四种植物的挥发性成分。建立了同时蒸馏萃取GC/MS法对这四种植物的挥发性成分进行了分析,并探讨了这四种植物挥发性成分的差异。从四种植物中共分离鉴定了105个挥发性成分,主要是萜类及其含氧衍生物。四种姜花属植物中含有多种活性成分,四者化合物组成相似,但黄姜花中各成分含量与其他三者区别较大。     

顶空固相微萃取-气相色谱/质谱联用法结合化学计量学分析白肋烟烘焙前后挥发性、半挥发性成分

采用顶空固相微萃取-气相色谱/质谱法（HS-SPME-GC/MS）分析了白肋烟烟叶中挥发性、半挥发性成分。20 mg烟粉在60℃条件下孵化8 min,采用聚二甲基硅氧烷/二乙烯基苯（PDMS/DVB）65 μm纤维头萃取40 min,然后在250℃解吸3 min,通过与标准品和质谱数据库进行比对,初步定性了白肋烟烟叶中122种挥发性、半挥发性成分,并采用内标法进行半定量分析。通过主成分分析（PCA）和偏最小二乘-判别分析（PLS-DA）等化学计量学方法,直观反映了白肋烟烘焙前后挥发性、半挥发性成分的变化。该方法具有样品用量小、前处理简单、灵敏度高等特点,结合化学计量学方法可用于白肋烟烘焙前后化学成分变化分析,为白肋烟烘焙条件的优化提供了科学的检测方法。     

利用薯蓣皂甙元完整骨架合成澳洲茄胺

澳洲茄胺1是中药龙葵生物活性成分澳洲茄碱和澳洲茄边碱的甙元, 具有抗肿瘤等生物活性. 利用薯蓣皂甙元的完整骨架, 以16-羟基甾体皂甙元的溴代开环反应为关键反应, 经9步反应, 以21%的总收率完成了澳洲茄胺1的合成.     

烟用香精中风味成分的提取条件的优化与测定

分别采用溶剂萃取、同时蒸馏萃取、固相微萃取和水蒸汽蒸馏等4种方法提取烟用香精B3样品中的挥发性和半挥发性风味成分,并采用信息量和重现性两个指标考察最优提取方案。正己烷溶剂萃取法具有相对较高的信息量和理想的重现性。通过GC和GC-MS进行定性定量分析,共鉴定了34种成分,定性了的成分占总成分的85．4％。     

气相色谱-三重四极杆质谱分析人参炮制品中的挥发性成分

人参炮制的化学成分变化研究主要集中在皂苷和糖类,本文首次从挥发性成分角度阐释了人参不同炮制品的物质基础。利用气相色谱-质谱联用(GC-MS/MS)方法,对鲜参、生晒参和红参中挥发性成分及其衍生规律进行研究。采用TG-5SILMS非极性气相色谱柱,以He为载气,通过NIST MS Spectral Database对挥发性成分进行检测并鉴定。鲜参、生晒参、红参中分别检出30、33和34种挥发性成分,其中生晒参中(-)-斯巴醇含量为鲜参含量的31.98倍,辛醛等8种挥发性成分为鲜参中含量的3倍以上,红参中有环癸等10种挥发性成分为鲜参中含量的3倍以上。生晒参和红参中各有4种挥发性成分在鲜参中未检出。     

超声微波酶解协同提取油茶壳中原花青素

建立了超声微波酶解协同提取油茶壳中原花青素的方法。通过单因素试验,探讨了超声微波协同提取油茶壳中原花青素过程中各主要因素对原花青素提取率的影响规律。实验中发现,往提取液中加入适量纤维素酶,可显著提高原花青素的提取率。在此基础上,通过正交试验,优化并获得了超声微波酶解协同提取原花青素的最适宜条件。最适宜提取条件为:超声波频率40 KHz、微波功率200 W、提取时间60 s、料液比1∶6、提取温度50℃、0.1%纤维素酶0.5 mL、提取次数2次。在最适宜条件下,原花青素的提取率为4.46%,分别是超声提取、微波提取和超声-微波协同提取的4.0、3.3和1.8倍。本文所建立的超声微波酶解协同提取油茶壳中原花青素的方法具有简便、快速、高效和节能等优势,有利于应用推广。     

用不同方法收集端红玉兰(Magnolia Rufidula Law et Zhou)鲜花香气的研究

利用XAD-4树脂吸附、微波加热后XAD-4树脂吸附、减压水蒸汽蒸馏加尾气吸附．乙醚浸提等方法收集端红玉兰(Magnolia rufidula Law et zhou)鲜花香气，并用色-质联用法分析。乙醚浸提方法获得的香成分最丰富，与其它方法收集的香成分基本一致。微波加热法所需样品少，收集时间短，效果良好。     

Preparation and characterization of fragrance by extracting the essential oils from different raw materials

The extraction is a simple process and it is widely used to extract the fragrances in fragrance industries from essential oils. There are number of compounds (i.e. flowers, oils, leaves etc.) from which we can prepare the fragrance by extracting the essential oils from them. In this work, we have prepared the fragrance from the essential oils by the liquid-liquid extraction process, where the essential oil presented as the concentrated hydrophobic liquid containing volatile aroma compounds. We used the combination of Gas chromatography and Mass spectrometry (GC/MS) characterization techniques to make our product more useful, convenient and compitative with the other fragrance available in the market. This study would be helpful to understand the preparation of the fragrance from the concentrated hydrophobic liquid type essential oils which contains volatile aroma compounds by using a significant liquid-liquid extraction process.     

Microwave extraction of essential oils from dried fruits of Illicium verum Hook. f. and Cuminum cyminum L. using ionic liquid as the microwave absorption medium

Ionic liquid was used as microwave absorption medium and applied to the extraction of essential oils from dried fruits of the Illicium verum Hook. f. and Cuminum cyminum L. by microwave‐assisted extraction. The extraction time is less than 15 min at the microwave power of 440 W. The constituents of essential oils obtained by the proposed method were compared with those obtained by hydrodistillation. There is no obvious difference in the constituents of essential oils obtained by the two methods.     

Effect of sample handling on alkaloid and mineral content of aqueous extracts of greater celandine (Chelidonium majus L.)

The authors examined the extraction of alkaloids from the greater celandine (Chelidonium majus L.) by different methods (traditional pressing and tea making, microwave and supercritical fluid extraction). The extractants were water and propylene glycol. For comparison of the extraction methods, the yield was evaluated according to total alkaloid content measured by spectroscopy. The highest alkaloid yield was obtained by microwave extraction and by making tea. Distribution of the components was studied by thin-layer chromatography and densitometry. The concentration and the ratio of alkaloid components in extracts are significantly different depending on the extraction method. The solution obtained by supercritical fluid extraction contains coptisine and chelidonine, while berberine could be obtained by microwave extraction only. Extracts with high coptisine content were obtained by supercritical fluid extraction, followed by pressing and microwave extraction. Mineral element content of the drug and extracts was also determined by inductively coupled plasma atomic emission spectrometry. Element content (Na, Ca, Fe) was found to be highest in microwave extracts.     

Controlled Thermal Release of L-Menthol with Cellulose-Acetate-Fiber-Shelled Metal-Organic Framework

Fragrances have been widely used in many customer products to improve the sensory quality and cover flavor defects. The key to the successful application of fragrance is to realize controlled fragrance release, which relies on the use of an appropriate carrier for fragrance. An ideal fragrance carrier helps to achieve the stable storage and controlled release of fragrance. In this work, a novel composite fragrance carrier with MIL-101 (Cr) as the fragrance host and cellulose acetate fiber (CAF) as the protective shell was developed. The encapsulation effect of MIL-101 (Cr) and the protective function of the CAF shell significantly improved the storage stability of L-menthol (LM). Only 5 wt % of LM was lost after 40 days of storage at room temperature. Encapsulated LM could also be effectively released upon heating due to the thermal responsiveness of CAF. In addition, the composite carrier was highly stable with neglectable Cr leaching under different conditions. The results of this work showed that the developed composite carrier could be a promising carrier for the thermally triggered release of fragrance.     

Non-polar Solvent Microwave-Assisted Extraction of Volatile Constituents from Dried Zingiber Officinale Rosc.

A new method, non-polar solvent microwave-assisted extraction （NPSMAE）, was applied to the extraction of essential oil from Zingiber officinale Rosc. in closed-vessel system. By adding microwave absorption mediumcarbonyl iron powders （CIP） into extraction system, the essential oil was extracted by the non-polar solvent （ether） which can be heated by CIP. The constituents of essential oil obtained by NPSMAE were comparable with those obtained by hydrodistillation （HD） by GC-MS analysis, which indicates that NPSMAE is a feasible way to extract essential oil from dried plant materials. The NPSMAE took much less extraction time （5 min） than HD （180 min）, and its extraction efficiency was much higher than that of conventional polar solvent microwave-assisted extraction （PSMAE） and mixed solvent microwave-assisted extraction （MSMAE）. It can be a good alternative for the extraction of volatile constituents from dried plant samples.     

高压微波辅助提取法提取牛黄上清丸中的黄芩苷

采用高压微波辅助提取法提取牛黄上清丸中的黄芩苷, 利用蜜丸的粘性, 将蜜丸涂敷在自制毛玻璃片表面后, 置于高压微波提取装置中进行提取, 同时与直接将蜜丸切块置于微波装置进行了对比.     

Application of ionic liquid‐based surfactants in the microwave‐assisted extraction for the determination of four main phloroglucinols from Dryopteris fragrans

An ionic liquid‐based surfactant combined with microwave‐assisted extraction method, followed by RP‐HPLC‐diode array detection (DAD) with a core shell column, was successfully applied in extracting and quantifying four major phloroglucinols from Dryopteris fragrans. Eight ionic liquids with different cation and anion were investigated, and 1‐octyl‐3‐methylimidazolium bromide presented the best relative extraction efficiency for four phloroglucinols. The optimum conditions of this method were as follows: ionic liquid concentration 0.75 M, liquid/solid ratio 12:1 mL/g, extraction time 7 min, extraction temperature 50°C, and irradiation power 600 W. The quality analytical parameters of the method were obtained based on the linearity, precision, accuracy, detection, and quantification limits. The recoveries were between 96.90 and 103.5% with standard deviations not higher than 4.7%. Compared with ionic liquid‐based heat reflux extraction, ultrasonic‐assisted extraction, negative‐pressure cavitation extraction, and conventional microwave‐assisted extraction, the relative extraction efficiencies of the proposed method for four phloroglucinols increased 1.5–40.4%. The method was successfully applied for the quantification of four major phloroglucinols from D. fragrans. All these results suggest that the developed method represents an excellent alternative for the extraction and quantification of phloroglucinols in other plant materials.     

中药刺五加叶中有效成分的几种微波辅助提取方法研究

利用高压微波提取法、常压回流微波提取法、流动微波提取法和索氏提取法提取中药刺五加中黄酮和皂苷类化合物,考察各种提取方法提取效率随时间的变化。结果表明,高压微波提取法在压力为300kPa,完全提取的时间为10min;常压回流微波提取法完全提取的时间为14min;流动微波提取法完全提取的时间为10min;索氏提取法需8h尚能完成。各种提取方法总黄酮的提取率分别为43．7、48．2、42．7和34．7mg／g;总皂苷的提取效率分别为60．2、61．5、59．8和46．5mg/g。与索氏提取法比较,微波提取法提取黄酮和皂苷,提取时间大大缩短,且提取效率显著提高。