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81.
Combinations of thyme, cowslip and liquorice roots are often used in the treatment of upper respiratory tract infections. Therefore the volatile fraction of herbal teas prepared from thyme (Thymus vulgaris) and the effect of combining with cowslip (Primula veris/P. elatior) and liquorice roots (Glycyrrhiza glabra) on the volatiles were analyzed. Volatile compounds were isolated by hydrodistillation and solid phase extraction and analyzed by GC-MS. Thymol was also quantified by HPLC. The total amount of volatiles as well the thymol content was decreased with increasing proportions of cowslip or liquorice in the infusion extracts whereas the proportion of monoterpene hydrocarbons increased. 相似文献
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84.
The research adopts open sampling method and TCT-GC/MS (Thermodesorption Cold Trap-Gas Chromatography/Mass Spectrometery) apparatus to collect and analyze the volatile organic compounds(VOCs) of Platycladus orientalis forest, with the intention of researching the compounds and diurnal variation of VOCs of P. orientalis forest in natural state in Beijing Western Hills in spring. The results are as follows: (1) There are 160 kinds (11 categories) of volatile organic compounds, containing Alkyl Hydrocarbon, Ketone, Alcohol, Acid, Aldehyde, Alkene, Ester, Aromatic hydrocarbon, Ether, Hydroxybenzene and Amide. The content of Alkyl Hydrocarbon, Ketone, Acid and Aldehyde occupy a greater percentage among all compounds. (2) The diurnal variation curve of total volatile organic compounds (TVOC) is characterized as "one peak at 11:00(36.44%) and one vale at 3:00(12.76%)". Generally, the concentration at daytime is higher than that of night, and higher in morning than in afternoon, with the maximum at noon. (3) The change of Alkyl Hydrocarbon concentration is greater in the morning and about midday, less in the afternoon and night. The diurnal variation curve of Ketone concentration appears as "three peaks and three vales". 1:00, 5:00—7:00 and 11:00 are peak time, 3:00, 9:00 and 17:00 are vale time. As to Acid, its concentration appears two obvious phases: the higher phase is from 9:00 to 17:00, with the maximum at 11:00, and the lower phase is from 19:00 to 7:00, with the minimum at 5:00. Concerning Aldehyde concentration, 17:00 and 19:00 are the higher phases and also has obvious difference with other time, while the lower phrase has no obvious difference with each other. (4) Alkene is the most important compound to human health. Its concentration appears as "one peak" at 15:00, which has obvious difference with other time. Totally, its content at daytime is higher than that at night, and higher in afternoon than in morning. 相似文献
85.
选择城市绿化重要树种圆柏为研究对象,探讨北美圆柏枝叶对小鼠自发活动及其生理生化指标的影响及挥发性物质与环境间的关系。采用旷场分析法,将入组的30只昆明小鼠分成3组:对照组、低剂量组和高剂量组,低剂量组和高剂量组分别对应地暴露于210 g和420 g圆柏枝叶中,每天4 h,连续处理6 d,观察小鼠各行为指标,结合医学手段分析小鼠相应的生理生化指标。结果表明,小鼠的中央格运动路程、总路程及中央格运动时间都呈现一定的剂量反应;体质量呈稳定增长趋势;生理指标正常,生化指标有部分超出正常范围。经低浓度枝叶挥发物处理的小鼠兴奋性增强,探究和认知能力增强,且其食欲没有受到影响,但是引起部分生化指标的异常,其作用机制还需进一步的探索。研究结果为圆柏作为生态保健树用于城市森林人居环境建设绿化配置提供科学依据。 相似文献
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以固相微萃取吸附采集木荷鲜花的香气成分,用GC/MS总离子流色谱峰的峰面积归一化法对木荷鲜花的挥发性成分进行了分析。鉴定结果表明,木荷鲜花能挥发出多种有益于人体健康的芳香气体物质,其香气成分包括:l-芳樟醇(16.83%)、桧烯(13.83%)、α-蒎烯(10.28%)、苯甲醇(8.78%)、3,7-二甲基-1,3,7-辛三烯(7.55%)、吉玛烯-D(5.23%)、2,6,6-三甲基环己-2-烯-1,4-二酮(4.84%)、反式-氧化芳樟醇(3.41%)、反式-石竹烯(3.14%)等48种化合物。结果为进一步研究及开发利用木荷林资源提供依据。 相似文献
88.
Fan Hui Li Jiquan Jin YoujuCollege of Biological Sciences Biotechnology Beijing Forestry University Beijing P. R. China 《中国林学(英文版)》2003,(1)
Electrophysiological and behavioral responses of adult A. glabripennis (Motsch.) to volatiles from ashleaf maple (Acer negundo L.) were investigated to identify semiochemicals involved in host location. Measurable electroantennogram (BAG) responses were elicited to all compounds tested, the most effective antennal stimulants were trans-2-hexen-1-al,decyl aldehyde and trans-2-hexenl-ol.These profiles were similar between males and females. In Y-tube olfactometer bioassays, above three compounds with certain concentration, trans-2-hexen-l-al (1%), trans-2-hexen-l-ol (1%) and decyl aldehyde (10%), were significantly attractive to the adults in laboratory. The results show that either BAG or olfactory responding to a particular volatile compound are markedly influenced by the concentration. 相似文献
89.
兴安落叶松鞘蛾对寄主挥发物的反应 总被引:2,自引:1,他引:2
运用触角电位仪(EAG)和"Y"型嗅觉仪测试鞘蛾对落叶松9种挥发物,即R-α-蒎烯、S-α-蒎烯、β-蒎烯、罗勒烯、水芹烯、3-蒈烯、月桂烯、莰烯和叶醇的EAG和行为反应.结果表明:在0.4 mol·L-1浓度下,雌蛾除了对R-α-蒎烯、雄蛾除了对R-α-蒎烯和水芹烯没有明显EAG反应外,对其余挥发物的EAG反应与对照相比差异均达到显著水平(P<0.05),并且雌、雄虫之间的EAG反应也存在一定的差异.利用"Y"型嗅觉仪测试鞘蛾对9种挥发物在0.000 4,0.004,0.04,0.4,0.8 mol·L-1这5个浓度梯度下的行为反应.结果表明:雌虫对S-α-蒎烯、S-β-蒎烯、水芹烯、3-蒈烯、月桂烯、叶醇这6种物质在一定浓度下表现出明显的趋向偏好(P<0.05);雄虫对罗勒烯、月桂烯、莰烯、叶醇这4种物质在一定浓度下表现出明显的趋向偏好(P<0.05).由于鞘蛾幼虫具有潜叶取食的特殊习性,为探索利用外源植物挥发物对其取食行为的调控作用,进一步筛选对雌虫有活性的挥发物成分,喷施到健康落叶松苗上,观察幼虫的取食行为.结果表明:喷施挥发物的样枝上,0.004 mol·L-1月桂烯造成幼虫的死亡虫数最少,与对照差异不显著(P>0.05),其他样枝上幼虫死亡率较对照差异极显著(P<0.01),表明挥发物可能对幼虫有致害作用,其中,S-α-蒎烯0.04 mol·L-1造成幼虫的死亡率最高,达86.67%. 相似文献
90.
[目的]本研究明确2种浓香型石斛花朵的香气成分及其含量,探明其香气组成,以期为石斛花的保健开发提供参考。[方法]采用顶空固相微萃取(HS-SPME)结合气相色谱-质谱联用(GC-MS)技术,分析了2种浓香型石斛花朵的挥发性成分。[结果]发现细叶石斛花含挥发性成分52个,翅梗石斛花含挥发性成分35个,主要成分皆为烯烃类。[结论]首次测定了翅梗石斛新鲜花朵的挥发性成分,其特征香气成分为罗勒烯、β-石竹烯和d-柠檬烯。细叶石斛花的特征香气成分为罗勒烯、β-石竹烯、芳樟醇。 相似文献