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1.
The Fraser fir (Abies fraseri) and balsam fir (Abies balsamea) are eastern North American conifers which have been infested by an exotic insect, the balsam woolly adelgid (BWA). BWA infestation has had particularly severe effects on Fraser fir, with up to 95% mortality rates at some sites, and is characterized by attack on mature trees only. The purpose of this research was to perform a chemosystematic study to evaluate whether differences in volatile chemical concentrations of various stands of fir were observed as a function of resistance to BWA infestation. The concentrations of volatiles were determined by a methylene chloride extraction procedure, followed by analysis by gas chromatography. First, comparisons were made of concentration levels of volatiles in Fraser and balsam fir foliage of seedlings, saplings, and mature trees. If a chemical provided resistance, one would expect higher volatile levels in the balsam foliage because of its greater resistance to BWA. Second, the volatile levels in Fraser fir saplings and mature trees at uninfested sites were compared to the levels in surviving Fraser fir saplings and mature trees at infested sites. For a compound that provided BWA-resistance, higher volatile levels would be expected at the infested site because of the greater resistance of the surviving trees. Lastly, the concentrations of volatiles in sapling foliage were compared to those in mature foliage, where higher levels of resistance-providing chemicals would be expected in the saplings. 3-Carene was shown to consistently follow the expected pattern for a compound that provides resistance against BWA and β-pinene followed the pattern for the majority of the comparisons. These results indicate that while maltol and total volatiles did not correlate with the expected pattern, 3-carene, and possibly β-pinene and sesquiterpenes may provide fir with defense against BWA infestation.  相似文献   

2.
The compositions of the mono- and sesquiterpenoids of the oleoresins of the Sakhalin fir (Abies sachalinensis Fr. Schmidt), Mayr's fir (Abies mayriana Miyabe et Kudo), and the slender fir (Abies gracilis Kom.) have been studied. In the oleoresin ofA. gracilis 37 compounds were identified, of which 11 were monoterpene hydrocarbons, seven were oxygen-containing monoterpenoids, 16 were sesquiterpene hydrocarbons, and three were sesquiterpene alcohols. In each of the oleoresins ofA. sachalinensis andA. mayriana eight oxidized monoterpenoids, 18 sesquiterpene hydrocarbons, and a sesquiterpene alcohol — bisabolol — were identified.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 195–199, March–April, 1980.  相似文献   

3.
Solid phase micro extraction (SPME) was investigated for the determination of volatile chemicals in the foliage of Fraser fir (Abies fraseri). Advantages of SPME include its speed, sensitivity, and ability to determine volatiles without chemical solvents. In this study, qualitative comparisons were performed of the volatiles emitted from living foliage (in situ), damaged living foliage (in situ damaged), and severed foliage (ex situ). These studies suggest that β-phellandrene and γ-terpinene may be emitted as a response to foliar injury. Comparisons were made of the volatiles collected by SPME with ex situ sampling to previous studies in our laboratory using methylene chloride extraction. Similar results were obtained by the two extraction methods.  相似文献   

4.
From the total extractive substances of the roots ofFerula stylosa two esters have been isolated: chimganin and a new one — stylosin. The structure of stylosin is suggested as the ester of 4-hydroxy-3-methoxybenzoic acid and the monoterpene alcohol fenchol.Azerbaidzhan SSR, Baku, and All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 789–791, November–December, 1980.  相似文献   

5.
Three new pyrroloazepine type alkaloids, stichoneurines A and B and 6-hydroxycroomine were isolated from the lipophilic root extracts of Stichoneuron caudatum and Stemona tuberosa collected in Thailand together with the already known croomine, tuberostemonine, and tuberostemonine A. The structures were elucidated by spectroscopic methods including H/H-COSY, HMQC, and HMBC. Information on the relative stereochemistries and conformational behaviour was obtained by analysis of the NOESY spectra. The formation of pyrroloazepine alkaloids in the genus Stichoneuron is reported for the first time and supports its affiliation to the family Stemonaceae. The occurrence of two different types of alkaloids, of the tuberostemonine and croomine series, in different geographical provenances of Stemona tuberosa is of special chemosystematic interest and may contribute to a more natural species delimitation within that complex group.  相似文献   

6.
Summary. Three new pyrroloazepine type alkaloids, stichoneurines A and B and 6-hydroxycroomine were isolated from the lipophilic root extracts of Stichoneuron caudatum and Stemona tuberosa collected in Thailand together with the already known croomine, tuberostemonine, and tuberostemonine A. The structures were elucidated by spectroscopic methods including H/H-COSY, HMQC, and HMBC. Information on the relative stereochemistries and conformational behaviour was obtained by analysis of the NOESY spectra. The formation of pyrroloazepine alkaloids in the genus Stichoneuron is reported for the first time and supports its affiliation to the family Stemonaceae. The occurrence of two different types of alkaloids, of the tuberostemonine and croomine series, in different geographical provenances of Stemona tuberosa is of special chemosystematic interest and may contribute to a more natural species delimitation within that complex group.  相似文献   

7.
Spruce–fir forests form unique ecosystems in the eastern United States and Canada. These forests are composed of Fraser fir (Abies fraseri) and red spruce (Picea rubens) in the Southern Appalachians, and balsam fir (Abies balsamea) and red spruce in the middle and northern Appalachians. Decline of spruce–fir forests has been observed since the 1960s that has been attributed, at least in part, to acidic deposition. Acidic deposition has been reported to decrease the availability of calcium and increase the availability of aluminum and induce decline of red spruce at high elevation sites above 1800 m. Aluminum, calcium, and magnesium were determined in Fraser fir, balsam fir, and red spruce foliage and soil from sites in the southern and middle Appalachians in order to evaluate whether acidic deposition may play a role in the decline of the conifers. Our nutrient studies did not provide any evidence that acidic deposition was affecting the conifers.  相似文献   

8.
The complete chemical composition of the oleoresin of the Chinese pine growing in the Far East has been studied. It has been shown that the main components of the monoterpenes are -pinene, -phellandrene, and -terpineol. The sesquiterpenes contain longifolene and compounds related to it. The oleoresin of the Chinese pine is distinguished by a high content of diterpene cembrane compounds. Among the resin acids, dehydroabietic acid predominates (42.4%).Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 444–448, July–August, 1984.  相似文献   

9.
A. Orav  T. Kailas  M. Liiv 《Chromatographia》1996,43(3-4):215-219
Summary The essential oils of Estonian spruce and pine needles have been analysed by a combination of steam distillation/extraction, GC and GC-MS. According to their monoterpene composition Estonian pines belong to a high carene chemotype with monoterpenes representing up to 85% of total oil. Estonian spruce needle oil contains up to 70% of oxygenated terpenes and more limonene and 1,8-cineole than the same spruce species [Picea abies (L.) Karst.] from other localities.A total of 60 components were identified. Coefficients of variation describe the range of component contents in individual trees within the population.  相似文献   

10.
根据刺五加挥发油中24个挥发性成分在5个程序升温条件下的保留时间,采用基于Levenberg-Marquardt法的软件GC_AB计算得到相应成分的气相色谱保留参数(A, B值)。通过对其中的萜烯及萜烯氧化物之间A, B关系的相关性分析,发现相同碳数的单萜烯、倍半萜烯和其氧化物分别具有良好的A-B线性相关性,但单萜烯与倍半萜烯、单萜烯与其氧化物、倍半萜烯与其氧化物的A-B关系不共线。研究表明,在中草药挥发油之类的复杂未知混合物体系的分析中,通过色谱保留参数进行萜烯及萜烯氧化物的分类是一种很有潜力的辅助定性方法。  相似文献   

11.
The chemical composition of the oleoresin of the Kamchatka larch has been studied. Mono-, sesqui-, and diterpenoids have been found in it. The monoterpenes were represented by nine components (the main one being 3-carene), and among the sesquiterpene hydrocarbons -element, longifolene, and germacrene D predominated. The main oxygen-containing diterpenoid was larixyl acetate. Seven resin acids were determined, the main one being isopimaric and palustric and/or levopimaric.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 790–793, November–December, 1985.  相似文献   

12.
A method is described for quantitative analysis of monoterpenes in western redcedar (Thuja plicata) foliage by gas chromatography with flame ionization detection. Response factors for monoterpenes identified in redcedar are evaluated to determine similarities among monoterpene responses. Evaluation demonstrates that redcedar monoterpenes yield detector responses that fall into two groups. One monoterpene from each group is used as a standard for quantitative analysis. Redcedar monoterpenes are quantitated by comparing analyte response with the response factor of one of the standards in single-point calibrations. Homogenized foliage samples are extracted with ethyl acetate and the extracts passed through a solid phase extraction column of graphitized carbon to remove plant pigments. Method bias and repeatability are evaluated by fortifying foliage samples with (1S)-(+)-carvone and (1S)-(+)-2-carene and subjecting the samples to the extraction and analysis procedures. Detection limits are also assessed from fortified samples. Excellent recovery (> 95.0%) and precision (< 5%) are obtained from the analysis of 2-carene from fortified samples. Carvone recovery is approximately 80% with excellent precision (< 4%). The method limits of detection obtained from 2-carene and carvone fortified samples are 4.7 and 13.5 microg/g, respectively.  相似文献   

13.
Fragrance monoterpenes are widely used commercially due to their pleasant scent. In previous studies, we have shown that air‐exposed monoterpenes form hydroperoxides that are strong skin sensitizers. Methods for detection and quantification of the hydroperoxides in essential oils and scented products are thus desirable. Due to thermolability and low UV absorbance, this is a complicated task. We have recently developed a sensitive LC–ESI‐MS method, but with limited structural information and separation efficiency for positional isomers and stereoisomers. In the present study, we investigated derivatization with a trimethyl silyl reagent and subsequent GC with electron ionization MS for the determination of monoterpene hydroperoxides. All investigated monoterpene hydroperoxides could be chromatographed as thermostable trimethyl silyl derivatives and yielded the fragment m/z 89 ([OSi(CH3)3]+) at a higher extent compared to corresponding alcohols. Limonene‐2‐hydroperoxide and four other hydroperoxide isomers of limonene were separated and detected in sweet orange oil autoxidized for two months. The concentration of limonene‐2‐hydroperoxide isomers was found to be 19 μg/mg in total. Also isomers of linalyl acetate hydroperoxide and linalool hydroperoxide were detected in autoxidized petitgrain oil (two months). The presented GC–MS method showed concentrations in the same order as previous LC–MS/MS analysis of the same type of oils.  相似文献   

14.
New photochromic (2Z)-2-(N-acyl-N-arylaminomethylidene)benzo[b]thiophen-3(2H)-ones containing L-amino acid derivatives as migrating groups were synthesized. Light irradiation of their solutions at 436 nm leads to the photoinduced acylotropic rearrangement N → O accompanied by migration of the chiral fragment. The bulky N-acyl group causes steric strain thus destabilizing the amide form of compounds and facilitating the photorearrangement. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2690–2696, December, 2005.  相似文献   

15.
An analytical separation has been performed of the essential oil of the bark of one-year winter shoots ofL. sukaczewii andL. sibirica. Out of the 37 terpenes detected, 13 monoterpenes have been identified. The two species have identical sets of monoterpenes with significant differences in their relative amounts.Botanical Garden-Institute, Ufa Scientific Center of the Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 640–642, September–October, 1994.  相似文献   

16.
The terpenoid compositions of the oleoresins of the oriental spruce and of the Nordmann fir growing in the Caucasus have been studied. From the oleoresin ofPicea orientalis (L.) Link, which belongs to the sectionOmorica, 32 mono-, sesqui-, and diterpene compounds have been identified, and fromAbies nordmanniana Stev. 37 mono-, sesqui, and diterpene compounds. Together with other diterpenoids that are characteristic for the oleoresins of all species of fir, methyl dehydroabietate and methyl 15-hydroxy dehydroabietate have been found in the oleoresin of the Nordmann fir. Three new sesquiterpene hydrocarbons have been isolated.  相似文献   

17.
A novel monoterpene, (1S, 2S, 6S)-(+)-1,6-epoxy-4(8)-p-menthen-2-ol, was isolated from an elicitor-treated cell culture of Cupressus lusitanica (Mexican cypress). Ten known monoterpenes--limonene, myrcene, beta-ocimene, sabinene, terpinolene, 4-terpineol, alpha-terpineol, 4(8)-p-menthen-1,2-diol, 4-hydroxyphellandric acid methylester and beta-thujaplicin methylether--were also identified. Regioselective metabolisms of monoterpenes were observed in this culture.  相似文献   

18.
Synthetic approaches to (±)- and (3S)-analogs of the AI component of the Aonidiella aurantii sex pheromone (3S)-methyl-6R-isopropenyldec-9-en-1-ylacetate based on stepwise alkylation of acetoacetic ester by 3-butenylbromide and 1,5-bifunctional 3-methylpentanes were investigated. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 589–591, November–December, 2005.  相似文献   

19.
A new monoterpene, sachalol, and three new monoterpene glycosides, sachalosides VI, VII, VIII, were isolated from Rhodiolae Radix, the roots of Rhodiola sachalinensis. The absolute stereostructures of new monoterpenes were elucidated on the basis of chemical and physicochemical evidence including the application of the modified Mosher's method.  相似文献   

20.
Conclusions It has been shown that an industrial sample of the turpentine oil from the oleoresin ofPinus silvestris contains, in addition to monoterpenes of the p-menthane series, monoterpenes of the m-menthane series: m-mentha-6,8-diene and m-mentha-1,3(8)-diene.Institute of Physical Organic Chemistry of the Academy of Sciences of the Belorussian SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 318–321, May–June, 1974.  相似文献   

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