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1.
The Lamiaceae is rich in aromatic plant species. Most of these species produce and store essential oils in specialised epidermal oil glands, which are responsible for their specific flavour. Two types of glands producing essential oil and possessing different morphological structure can be found in Salvia sclarea : peltate and capitate glands. The content of single oil glands from different positions on the plant (corolla, calyx and leaf) were sampled using an SPME fibre and analysed by gas chromatography in order to study variability of the essential oil composition. It was found that the composition of terpenoids is quite variable within an individual plant. Capitate oil glands mainly produce three essential oil compounds: the monoterpenes linalool and linalyl acetate, and the diterpene sclareol. Peltate oil glands, however, accumulate noticeable concentrations of sesquiterpenes and an unknown compound (m/z = 354). Furthermore, the oil composition varies within each gland type according to the plant organ. Linalool and linalyl acetate are characteristic substances of flowers, whereas the sesquiterpenes occur in higher proportions in leaves. Even within one gland type on a single leaf, the chemical variability is exceedingly high.  相似文献   

2.
Small-scale GC headspace analyses combined with SPME sampling of individual oil glands have been used to measure the variation in volatile content and composition in and within different oregano plants as affected by age, season and developmental state. The main monoterpenes found were p-cymene, carvacrol and their precursor gamma-terpinene. The early season preponderance of p-cymene over carvacrol was reversed as the season progressed and this pattern could also be seen at any time within the plant, from the latest leaves to be produced (low in cymene) to the earliest (high in cymene). Seedlings from the same mother plant developed this pattern at different rates. Within individual leaves the pattern was not observed, even within the youngest developing leaves. However it was found that the oil composition of individual glands within a single leaf varied considerably, most notably in respect of the production of carvacrol and its isomer thymol.  相似文献   

3.
The antifungal activities of cinnamon oil, clove oil, anise oil, and peppermint oil, and their main components (cinnamaldehyde, eugenol, trans-anethole, and menthol, respectively) against molds identified from areca palm leaf sheath (Mucor dimorphosporus, Penicillium sp., Aspergillus niger, and Rhizopus sp.) were investigated. An agar dilution method was employed to determine the minimum inhibitory concentration (MIC) of essential oils and their main components. Zone inhibition tests and the inhibitory effect of the leaf sheath dip-treated with essential oils against those molds were examined. Major components of essential oils on the leaf sheath during storage were quantified by gas chromatography analysis. The MIC values of essential oils on agar and on the leaf sheath were identical. With an MIC of 50 ??g ml−1, cinnamon oil had the strongest inhibitory effect. At their MICs the oils were capable of providing protection against mold growth on the leaf sheath for at least 12 weeks during storage at 25 °C and 100% RH. Scanning electron microscope examination showed that essential oils prevented spore germination. Except for menthol in peppermint oil, the main components of the essential oils, which were fairly stable over the storage period, largely contributed to the antifungal activity.  相似文献   

4.
The accumulation of terpenoid oil was examined in the leaves of Eucalyptus polybractea at scales ranging from individual oil glands to the whole plant. Variations in oil composition and concentration of oil were measured and related to both morphological and physiological parameters. Within a plant, all glands produced oil of broadly similar composition that was not regulated by leaf age or the position of the gland within the leaf. There were, however, distinct differences between plants, suggesting that composition is controlled primarily at the whole-plant level. Oil concentration, too, was regulated primarily at the whole-plant level and was limited by gland capacity. Gland capacity was linked to leaf area and thickness, the final products of leaf expansion. Leaf and plant oil composition is determined not by a mosaic of glands specializing in producing a single or a small group of compounds, but rather by glands with remarkably similar capacities for terpenoid biosynthesis, although oil concentration, limited by gland capacity, may be linked to leaf expansion rather than biosynthetic capacity.  相似文献   

5.
Foliar secretory cavities, commonly called leaf pellucid glands, have been reported in many families of vascular plants. In the Rubiaceae, these structures have only been found in the sister genera Rustia and Tresanthera, which are also anomalous within the family because they have poricidal anthers, and in the distantly related Heterophyllaea. General leaf anatomy, with particular attention to secretory cavities, as well as the chemical analysis of the secreted substances of Rustia formosa, is presented here for the first time. The secretory structures have been found in the lamina between the palisade and spongy parenchymas and in the cortical region of the petiole. The chemical analysis showed that the essential oil secreted is a complex mixture of at least 75 components, mostly of sesquiterpenoid composition. Illustrations of the leaf anatomy, details of the secretory structures of Rustia formosa, a gas chromatogram, and a table of the principal components of the leaf essential oil are included.  相似文献   

6.
In the study, we evaluated chemical composition and antimicrobial, antibiofilm, and antitumor activities of essential oils from dried leaf essential oil of leaf and flower of Agastache rugosa for the first time. Essential oil of leaf and flower was evaluated with GC and GC–MS methods, and the essential oil of flower revealed the presence of 21 components, whose major compounds were pulegone (34.1%), estragole (29.5%), and p-Menthan-3-one (19.2%). 26 components from essential oil of leaf were identified, the major compounds were p-Menthan-3-one (48.8%) and estragole (20.8%). At the same time, essential oil of leaf, there is a very effective antimicrobial activity with MIC ranging from 9.4 to 42 μg ml−1 and potential antibiofilm, antitumor activities for essential oils of flower and leaf essential oil of leaf. The study highlighted the diversity in two different parts of A. rugosa grown in Xinjiang region and other places, which have different active constituents. Our results showed that this native plant may be a good candidate for further biological and pharmacological investigations.  相似文献   

7.
裂叶荆芥不同部位香精油组成研究   总被引:1,自引:0,他引:1  
采用水蒸气蒸馏法,分别从裂叶荆芥的叶、茎和花三个不同部位提取香精油并进行气相色谱/质谱分析.结果发现,叶、茎、花的香精油分别含有23、29、26种组分.叶和花香精油的组成和含量基本相似,主要成分是含量分别为15.09%、14.51%的薄荷酮和29.26%、31.36%的(+)-胡薄荷酮等单萜化合物以及含量分别为17.09%、5.00%的α-律草烯等倍半萜.而茎香精油的萜类化合物含量较低,含薄荷酮为4.15%,(+)-胡薄荷酮为7.68%,但其乙酯含量相对较高,如(E)-9-十六碳烯酸乙酯含量为11.92%,异戊酸乙酯为9.38%.  相似文献   

8.
Alterations in essential oil gland number, distribution and fine structure, and the oil content in the leaf of Mentha arvensis L. were examined during its growth and senescence. Accumulation of essential oil occurred predominantly during the rapid leaf expansion phase followed by a similar decline. The oil gland (trichome) number increased upto leaf maturation and declined thereafter. Initially, cuticle remains tightly apposed to the secretory head of oil glands but progressively a sub-cuticular space appears to be created for the oil. Considerable enlargement of vacuole with ageing is witnessed, whereas cytoplasm gradually decreases to a thin peripheral layer. Some secretory cells from senescing leaf were found almost empty, having only a few remnant oil droplets. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

9.
【目的】为探讨马缨丹Lantana camara L.叶片精油化学成分以及其对3种害虫的生物活性,以应用于生物防治。【方法】马缨丹叶片经水蒸气蒸馏法提取精油,产率为0.21%。经过气-质联用仪(GCMS)分析,从马缨丹叶片精油中检测出主要的26种化合物,其中α-姜黄烯(α-curcumene,32.76%),β-石竹烯(β-caryophyllene,16.36%),石竹烯氧化物(Caryophyllene oxide,12.22%),桉油烯醇(Spathulenol,10.48%)含量较高,并对3种不同害虫进行生物活性测定。【结果】生物测定结果表明,马缨丹精油对米象Sitophilus oryzae成虫和Ⅳ龄埃及伊蚊Aedes aegypti幼虫的触杀效果显著,LC50分别为0.92 mg/cm2和32.33μg/m L。随着浓度的升高,对白蚁驱避作用增强,白蚁死亡率增加;高浓度精油对白蚁有触杀作用,但较低浓度对白蚁无显著影响。【结论】本研究证明马缨丹叶片精油对3种害虫有良好防治的效果。  相似文献   

10.
The chemical constituents of the essential oils from the leaves of Laurus nobilis L., have been identified both by capillary GC-MS and fused silica capillary GC Kovats retention in,lex of components. From laurel leaf oil, 45 compounds have been identified, among which, 19 compounds such as 1,4-cineole, sabinene hydrate etc. have not been found in the leaf oil previously. This paper studies systematically the constituents of essential oil from dry, fresh leaves, and those of annual, perennial, different district, and reported the changes of the chemical constituents month by month. Results showed that the yield of essential oil and 1,8-cineole content is the highest in July.  相似文献   

11.
月桂叶精油成分及逐月动态变化   总被引:1,自引:0,他引:1  
采用毛细柱 GC-MS 和弹性石英毛细柱 GC Kovats 指数的鉴定方法,从月桂(Laurusnobilis L.)叶精油中鉴定出45个化合物,其中1,4-桉叶油素、水合桧烯等19个系该种植物中首次报道。系统地研究了月桂干叶与鲜叶、不同产地、当年生与多年生成分,首次报道月桂叶精油成分逐月动态变化,表明其得率和主成分1,8-桉叶油素含量均以7月最高。  相似文献   

12.
The osmanthus volatile oil was welcomed by consumers even if the high price since the unique and pleasant odor. Meanwhile, the low yield of osmanthus volatile oil restricts industrial production. In this work, an osmanthus volatile oil was obtained by means of a novel ultrasonic-assisted flash extraction method and was compared with the oil from hydrodistillation and supercritical fluid extraction on yield, aroma, and biological activities. The volatile oil obtained from the ultrasonic-assisted flash extraction was obtained with the petroleum ether and got a high yield at 3.51 % within a 40-min process, an increase of nearly 81 % from the single solvent extraction. This oil also showed a high aroma intensity and aroma compound concentration. Meanwhile, the oil also has the highest antioxidant ability but lower antibacterial activity against oil from hydrodistillation. It was considered that this work was helpful for the optimization of the extraction method of osmanthus volatile oil.  相似文献   

13.
The leaf, stem bark and root bark oils of Isolona cooperi Hutchinson & Dalziel from the Ivory Coast have been analysed by GC (retention index), GC-MS and 13C-NMR spectroscopy. Two types of essential oil were produced by the plant. The leaf and stem bark oils were monoterpene-rich, containing principally (Z)-beta-ocimene and gamma-terpinene and three lactones, 5-[(E and Z)-hexylidene]-5H-furan-2-ones and massoia lactone, were present in appreciable amounts. Conversely, the root bark oil was dominated by 5-isopentenylindole and (E)-beta-caryophyllene. The strategy for the analysis of each oil was adapted according to the nature of the components.  相似文献   

14.
为了分析不同年限巨尾桉叶挥发油的化学成分及生长年限对化学成分组成的影响,采用水蒸气蒸馏法,分别提取2006~2010年种植的巨尾桉叶片中的挥发性成分,并用气相色谱质谱联用技术分析鉴定其化学成分。结果表明:不同生长年限的巨尾桉叶片挥发油产量在0.55%~1.35%之间,随生长年限的增加而升高。利用GC-MS共鉴定出63个化合物,占总挥发油的93.00%~97.07%。其中相对含量较高的物质为:1,8-桉叶油素(55.72%~63.47%)、α-松油醇(9.78%~14.15%)、乙酸松油酯(4.96%~7.06%)、α-蒎烯(0.99%~4.31%)、龙脑(2.40%~4.89%)。由于生长年限的不同,挥发油中物质的组成及相对含量均存在差异。  相似文献   

15.
1.罗汉果根、茎、叶的结构与葫芦科其它植物大致相似;不同之处有三方面:(1)叶子主脉中维管束为5个:(2)叶子中有硅质细胞成群分布;(3)块根具异常次生生长;在次生木质部中围绕导管形成形成层,由之分化出多个具韧皮部与木质部的小维管束。2.叶中的硅质细胞分布于表皮、栅栏组织、海绵组织中,多个细胞集合在一起。其细胞壁加厚并硅质化,细胞内容物消失。推测与增加叶子的支持力量有关。3.罗汉果雌株叶子上、下表皮气也数之比为0.04,雄株为0.03,比值均很低,同时根据叶的解剖结构推测罗汉果为C3植物。4.雌株叶子下表皮单位面积气孔数比雄株的多26%,差异很显著,值得进一步研究简化观察统计方法,以用于鉴别幼苗的性别。  相似文献   

16.
Secondary metabolites obtained from the indigenous plants with proven mosquito control potential can be used as an alternative to synthetic insecticides under the integrated vector control. The essential oil extract from the forest redgum, Eucalyptus tereticornis Sm. (Myrtaceae) was tested against mature and immature mosquito vector Anopheles stephensi Liston (Diptera) under laboratory condition. The extract showed strong larvicidal, pupicidal and adulticidal activity. The leaf oil extracts showed high bioactivity at high doses. Results obtained from the laboratory experiment showed that the leaf extracts suppressed the pupal and adult activity of Anopheles stephensi at higher doses. In general, first and second instar larvae were more susceptible to all treatments. Clear dose -response relationships were established with the highest dose of 160ppm plant extract evoking almost 100% mortality. The results obtained suggest that, in addition to their medicinal activities, E. tereticornis can also serve as a natural mosquitocide.  相似文献   

17.
以供试的5个高油玉米优良自交系为材料,建立了一个高效的高油玉米幼胚再生体系.研究表明,高油玉米幼胚组织培养的最适幼胚长轴长度在0.5 mm~2.0 mm左右;MB培养基是最适的胚性愈伤组织诱导培养基;各材料胚性愈伤组织诱导率差异较大,以4K261和4K296的胚性愈伤诱导率较高;不同材料最适的继代培养条件存在差异,但基因型仍然是决定各自交系胚性愈伤组织的继代能力的主导因素,其中以4K261最佳.5个自交系均能分化出幼苗,但分化率差异较大,以4K059分化率最高,达82.0 %;其次是4K261和4K296,分别为63.2 %和59.0 %;4K060和4K061表现最差.所以4K059、4K261和4K296均可作为遗传转化的受体材料.该体系的建立为高油玉米的遗传转化奠定了基础.  相似文献   

18.
Summary Levels of insect attack and yields of leaf essential oils in Eucalyptus vary widely within and among species. We tested the hypotheses that 1) metabolic cost of oil detoxification increases with increasing oil yield, resulting in lower herbivore growth rates and, consequently, 2) in lower herbivore damage to plants. Distribution of insect damage, eggs, immature insects and adults and feeding rates, growth and survivorship of insects do not support the hypotheses, although a threshold level of oil may be necessary to influence herbivorous insects. Herbivorous beetles tested do not detoxify essential oils. Levels of leaf nitrogen, rather than oil content, explained differences in insect feeding and growth.  相似文献   

19.
The levels of starch, soluble sugars, starch mobilizing enzymes(amylases and phosphorylase) and sodium [2-I4C] acetate incorporationinto essential oil have been examined during leaf ontogeny oflemongrass (Cymbopogon flexuosus Stapf., cv. OD-19). The degradationof starch was predominantly amylolytic and ß-amylasewas the major enzyme involved. Its activity was quite high duringthe period of active leaf growth accompanying active accumulationof essential oil. The activities of a-amylase and phosphorylasewere relatively lower. The change in starch to soluble sugarsratio was inversely related to ß-amylase activity.The time-course (12 h light followed by 12 h dark) monitoringof the [I4C]-radioactivity in starch and essential oil, afterexposure of the immature (15 days after emergence) leaf to 14CO2,revealed a progressive loss of label from starch and a parallelincrease in radioactivity in essential oil. The results havebeen discussed in relation to degradation of transitory starchserving as the source of carbon precursor for essential oil(monoterpene) biogenesis in the tissue. The amount of exogenouslysupplied acetate incorporated into essential oil increased tremendouslywith 5-10 fold decrease in specific activity of the labelledacetate (2,110 GBq mole–1). The effect was largely manifestedin ‘citral’, the chief (ca. 80%) constituent oflemongrass essential oil. Ontogenetically, the amount of essentialoil synthesized from the exogenously supplied precursor (acetate)was much higher in young (10 days after emergence) than in mature(30 days after emergence) leaf. Thus, the leaf developmentalphase influences the expression of essential oil metabolismand actual synthesis. Only young lemongrass leaves are substantiallyactive to synthesize essential oil. The oil biosynthetic phaseappears to be coordinated/integrated with the development ofelevated levels of certain primary metabolic activities likestarch mobilization. 1CIMAP Publication No. 706 2Present address: CSIR Complex, Palampur-176 061, Kangra Distt.Himachal Pradesh, India J Present address (until October 10, 1991): Department of Biology,Queen's University, Kingston, Ontario, K7L 3N6, Canada (Received November 30, 1990; Accepted May 31, 1991)  相似文献   

20.
GC-MS分析伊犁绢蒿挥发油化学成分   总被引:1,自引:1,他引:1  
利用水蒸气蒸馏法提取伊犁绢蒿挥发油,出油率为0.25%。采用色谱-质谱-计算机联用技术,从检出的30个成分中鉴定出28个,所鉴定成分占挥发油色谱总峰面积的98.66%。其主要化学成分为α-苎酮(78.74%)、樟脑(6.17%)、桧烯醇乙酸酯(1.94%)、β-苎酮(1.40%)、乙酸乙酯(1.14%)等,占总挥发油成分的89.46%。  相似文献   

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