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不同方法提取艾纳香叶挥发性成分的气相色谱-质谱分析 总被引:1,自引:0,他引:1
采用气相色谱-质谱法(GC-MS)分析水蒸汽蒸馏法(SD)、同时蒸馏萃取法(SDE)和顶空固相微萃取法(HS-SPME)3种方法提取的艾纳香叶挥发性成分。结果表明:3种方法提取艾纳香叶挥发性成分中主要是醇类和烯类化合物,其中萜类物质占较大比例。3种方法的提取物中分别鉴定出化合物50种(SD)、24种(SDE)和49种(HS-SPME)。水蒸汽蒸馏法和同时蒸馏萃取法提取的油状挥发物中主要成分相似,水蒸汽蒸馏法提取油状挥发物与顶空固相微萃取法提取挥发性成分的种类和相对含量相似,同时蒸馏萃取法提取油状挥发物中低沸点化合物较少。 相似文献
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直接进样法分析烟草挥发性和半挥发性酸性成分 总被引:11,自引:2,他引:11
使用同时蒸馏萃取法,把从烟叶中萃取出的挥发性、半挥发性酸性成分,不经衍生化进行了气相色谱(GC)分析和气相色谱/质谱(GC/MS)鉴定。从一种烤烟中鉴定出了19种酸性成分,并对这些酸性成分进行了定量测试。本文还讨论了使用该方法测定烟叶中酸性成分的重复性及回收率。结果显示,该方法适宜分析不少于六个碳的挥发性、半挥发性酸性成分。其中包括β-甲基戊酸、肉豆蔻酸、棕榈酸、油酸、亚油酸、亚麻酸等重要酸性香味成分的测定。 相似文献
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为了分析不同方法萃取苦荞样品中挥发性物质的差异,采用同时蒸馏萃取法(SDE)和固相微萃取法(SPME)提取苦荞样品中的挥发性成分,用气相色谱-质谱联用(GC-MS)技术定性鉴定,并用总离子流色谱峰的峰面积进行归一化定量分析。同时蒸馏萃取-气谱-质谱法(SDE-GC-MS)分析出23种挥发性成分,固相微萃取-气相色谱-质谱法(SPME-GC-MS)分析出35种挥发性成分,2种方法均提取出酯类、烃类、酮类、醛类和醇类,其中酯类和醛类的含量较多,说明酯类和醛类对苦荞的风味贡献较大。同时蒸馏萃取法适合对高沸点、低挥发性物质进行分离,固相微萃取法具有快速简便、不使用溶剂和样品检测非破坏性等优点,适合易挥发性化合物的检测。将两种提取方法相结合对苦荞挥发性物质提取能得到比较全面的结果。 相似文献
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蒌叶鲜叶具有独特的辛香味,在我国南方地区常用作嚼槟榔青果的植物配料。为了探究蒌叶鲜叶的挥发性成分,采用气相色谱-串联质谱仪对不同方法(水蒸气蒸馏法、固相微萃取法、超声辅助正己烷法和超声辅助二氯甲烷法)提取的挥发性成分进行分析。结果显示,4种方法提取和鉴定出的挥发性成分共92种,相对含量较高为酚类、烯类、酯类和醇类,主要成分为蒌叶酚、乙酸丁香酚酯、香叶烯D、4-烯丙基邻苯二酚二乙酸酯、β-石竹烯、γ-衣兰油烯等;水蒸气蒸馏法提取的挥发性成分最多,共鉴定60种;固相微萃取法、超声辅助二氯甲烷和超声辅助正己烷法提取鉴定的挥发性成分分别为53种、42种和25种;4种提取方法共有组分17种,而固相微萃取法特有成分20种,水蒸气蒸馏法获得特有成分18种。不同提取方法获得挥发性成分的种类和含量差异较大,以挥发性活性成分为目的的提取方法,水蒸气蒸馏提取法较为合适,固相微萃取法结合水蒸气蒸馏法提取蒌叶鲜叶,能够获得更加全面的挥发性成分,可为蒌叶香气物质基础的开发与利用提供参考。 相似文献
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为探究不同提取方法以及不同提取参数对花椒提取物挥发性物质组成的影响,以红花椒为原料,通过油浸法浸提、水蒸气蒸馏及超临界CO2萃取获得花椒提取物,采用固相微萃取与气相色谱质谱联用法测定花椒提取物中挥发性物质种类及含量,并通过主成分分析法及相对气味活度值评价提取物品质。对三种提取方法鉴定出的挥发性物质总数进行统计,发现油浸法、水蒸气蒸馏法和超临界CO2萃取法提取物中分别鉴定出挥发性物质65种、100种和82种。超临界CO2萃取法得到花椒提取物中挥发性物质含量最高为13909.90 μg/mL、水蒸气蒸馏法次之为1152.61 μg/mL、油浸法最低为249.38 μg/mL,对香气物质进行主成分分析发现各组得分与香气物质总含量在各单因素条件下的变化趋势相同。其中油浸法在料液比1:5、浸提时间5 h、浸提温度140℃时,水蒸气蒸馏法在料液比1:10、浸提时间2 h时,超临界CO2萃取法在乙醇添加量7%、乙醇添加比例85%时挥发性物质总含量及香气物质综合得分最高。相对气味活度值结果表明三种提取方法样品关键香气物质不同,油浸法样品中月桂烯对香气贡献最大,水蒸汽蒸馏法样品中芳樟醇与桉树醇对香气贡献最大,超临界CO2萃取法样品中芳樟醇对香气贡献最大。综上所述,提取方法的差异会导致挥发性物质,特别是关键香气物质种类与含量的显著变化,超临界CO2萃取法提取物中挥发性物质与香气物质含量高于其他两种提取方法。 相似文献
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了解河南省部分食品中重金属污染的现状。方法 在河南省18个省辖市采集8大类3 657份食品样品,按照国家标准检测食品中铅、镉和汞的含量,检测结果按照GB 2762—2012《食品安全国家标准食品中污染物限量》进行评价。结果 河南省部分食品中铅含量的平均值为0.34 mg/kg,总体超标率为8.8%(320/3 656),其中粮食、肉类和蔬菜中超标率较高,分别为17.2%(95/552)、14.5%(85/587)和10.7%(57/534);部分食品中镉含量的平均值为0.054 mg/kg,总体超标率为3.9%(143/3 657),其中食用菌和蛋类中超标率较高,分别为9.6%(49/508)和8.1%(42/518);部分食品中汞含量的平均值为0.077 mg/kg,总体超标率为8.3%(303/3 657),其中蔬菜和粮食中超标率较高,分别为25.3%(135/534)和12.3%(68/551)。结论 河南省部分食品中铅、汞污染情况较为严重,其中粮食、蔬菜和肉类食品中污染情况尤为突出,需要加强监管。 相似文献
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Objectives
To analyse trends in smoking prevalence in Ukraine from three surveys conducted in 2001–5, and to explore correlates of observed changes, in order to estimate the stage of tobacco epidemic in Ukraine.Design
Repeated national interview surveys in Ukraine in 2001, 2002 and 2005.Main outcome measure
Prevalence of current smoking among the population aged ⩾15 years.Results
The age‐standardised prevalence of current smoking in Ukrainian men was 54.8% in 2001 and 66.8% in 2005. Among Ukrainian women, prevalence increased from 11.5% in 2001 to 20.0% in 2005. ORs for yearly increase in prevalence were estimated as 1.164 (95% CI 1.111 to 1.220) for men and 1.187 (1.124 to 1.253) for women, which implies that, on average, 3–4% of men and 1.5–2% of women living in Ukraine join the smoking population each year.Conclusions
In Ukraine, smoking prevalence is increasing in most population groups. Among men, the medium deprivation group with secondary education has the highest smoking prevalence. Among women, while the most educated, young and those living in larger cities are the leading group for tobacco use, other groups are also increasing their tobacco use. Tobacco promotion efforts appear to have been significantly more effective in Ukraine than smoking control efforts. The decrease in real cigarette prices in Ukraine in 2001–5 could be the main factor explaining the recent growth in smoking prevalence.Ukraine is a large eastern European country with high smoking prevalence. Tobacco products are widely available at very low prices, and the transnational tobacco industry is extremely successful in promoting its products and lobbying for its interests in the legislative field. Advocacy of tobacco control has only recently achieved some success in the legislative field, with the first tobacco control law being adopted in late 2005. Ukraine ratified the Framework Convention on Tobacco Control in 2006, but there is still much cause for concern regarding the enforcement and effectiveness of the adopted legislative measures. Unfortunately, the government is not yet involved in nationwide surveillance of the tobacco problem, and the available data have mostly been gathered with funding from foreign donors. Several attempts have been made to measure the extent of the tobacco epidemic in the countries of the former Soviet Union (FSU).1,2,3,4,5,6,7 Most of these studies have shown rather high smoking prevalence among men (50–70%) and comparatively low prevalence among women (5–20%). Most countries in the FSU have similar smoking rates, while certain trends are shown to be related to the differences in how the transnational tobacco industry succeeds in every national tobacco market.6 Unfortunately, few studies have been published showing trends in smoking prevalence in the FSU.7 In Ukraine, two studies3,4 provided point estimates of smoking prevalence.The aim of this study was to analyse trends in smoking prevalence in Ukraine, on the basis of three surveys conducted in 2001–5, and to explore correlates of observed changes in order to estimate the stage of the tobacco epidemic in Ukraine. 相似文献17.
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