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1.
Aeciospores of Cronartium fusiforme isolated from slash pine (Pinus elliottii) trees were analyzed for volatile terpenoids by GLC and GLC-MS. α-Pinene, β-pinene, Δ3-carene, myrcene, linonene, β-phellandrene, and δ-terpinene were the major monoterpenoid hydrocarbons present with only traces of camphene. A number of monoterpenoid alcohols were also present of which terpinen- 4-ol predominated. Among the various acyclic sesquiterpenes present, β-farnesene and β-citronellol were identified. Several aromatic compounds were also observed, including o-cresol.  相似文献   

2.
The composition and concentration of monoterpenoids in the leaves and stems ofArtemisia feddei andArtemisia scoparia were determined, and seasonal variation in the monoterpenoids ofArtemisia species were investigated. The two species possessed different compositions and concentrations of monoterpenoids. The total amount of monoterpenoid inA. scoparia was always higher than that of A.feddei, and the monoterpenoid yields of leaves were higher than stem yields in both species as compounds formed. The major constituents of A.scoparia were 25 while A.feddei consisted of 26 compounds. Sixteen common monoterpenoid compounds were found in both plants. Large differences in the relative amounts of the monoterpenoids were found between species and seasons. Extremely large differences in the relative amounts of naphtalene, sabinene, β-pinene, cyclohexene, and octatrine were found in the leaf monoterpenoids of the two species. The largest differences in relative amounts of stem monoterpenoids were in s abinene and β-pinene levels.  相似文献   

3.
A method for the assay of uridine diphosphate (UDP)-glucuronosyltransferase activities toward some phenolic compounds and monoterpenoid alcohols is described. The method is based on the disappearance of the free substrate after incubation with microsomes and UDP-glucuronate. This disappearance is recorded using a gas chromatographic process. This method has been used, for example, to characterize the glucuronidation process of eugenol (4-allyl-2-methoxyphenol). The method could be extended to other substrates. Analytical conditions are given for some of them, especially monoterpenoid alcohols since the studies of their conjugations are a growing field of interest in evaluation of heterogeneity of UDP-glucuronosyltransferase. The method could also be used with other biological materials including cell suspension and crude liver biopsies.  相似文献   

4.
Two new monoterpenoid indole alkaloids, melohenryines A and B (1 and 2), along with six known indole alkaloids, were isolated from the twigs and leaves of Melodinus henryi. Structures of the new alkaloids were established by extensive spectroscopic techniques including NMR spectroscopy and mass spectrometry. Melohenryine A (1) represents the first example of monoterpenoid indole alkaloids characterized an ester carbonyl group at C-19 position. All of the new compounds were evaluated for in vitro cytotoxicity against several human cancer cell lines.  相似文献   

5.
The phytochemical investigation of leaves of Melaleuca alternifolia (Maiden & Betche) Cheel led to the isolation of a new monoterpenoid glycoside derivative melaleuoside (1), together with four known monoterpenoid glycoside derivatives (25). Structure elucidation of these compounds was performed based on NMR spectral data and MS. Compounds 25 were isolated from the genus of Melaleuca for the first time. Furthermore, we also discussed the chemotaxonomic significance of the isolates in this thesis.  相似文献   

6.
Cortical essential oil from Pseudotsuga macrocarpa was analyzed for monoterpenoid compounds. Only minor differences were apparent between samples collected in different locations. Pseudotsuga macrocarpa and P. menziesii appeared to be quite distinct chemically. No evidence was obtained of any gene exchange between the two species in the southern California coastal region, where they grow a short distance from each other.  相似文献   

7.
The major components of the isoprenoid-rich essential oil of Artemisia annua L. accumulate in the subcuticular sac of glandular secretory trichomes. As part of an effort to understand isoprenoid biosynthesis in A. annua, an expressed sequence tag (EST) collection was investigated for evidence of genes encoding trichome-specific enzymes. This analysis established that a gene denoted Adh2, encodes an alcohol dehydrogenase and shows a high expression level in glandular trichomes relative to other tissues. The gene product, ADH2, has up to 61% amino acid identity to members of the short chain alcohol dehydrogenase/reductase (SDR) superfamily, including Forsythia × intermedia secoisolariciresinol dehydrogenase (49.8% identity). Through in vitro biochemical analysis, ADH2 was found to show a strong preference for monoterpenoid secondary alcohols including carveol, borneol and artemisia alcohol. These results indicate a role for ADH2 in monoterpenoid ketone biosynthesis in A. annua glandular trichomes.  相似文献   

8.
Phytochemical investigation on the aerial parts of Psychotria yunnanensis led to the isolation of four norisoprenoids (1–4), one monoterpenoid (5), and eleven phenolic compounds (616). To our knowledge, all compounds were isolated from this plant for the first time. Compounds 2–16 were reported for the first time from the genus Psychotria. The chemotaxonomic significances of these compounds were summarized.  相似文献   

9.
《Phytochemistry》1999,52(7):1239-1254
Epicuticular waxes from the aphid-resistant red raspberry (Rubus idaeus) cultivar Autumn Bliss and the aphid-susceptible cultivar Malling Jewel were collected from the newly emerging crown leaves, and also from the group of four more mature leaves immediately below the crown. Resistance and susceptibility status of the leaves to infestation by the large raspberry aphid, Amphorophora idaei, were determined by bioassay with the insect just prior to collection of the wax. Analysis showed the waxes to consist of a complex mixture of free fatty acids; free primary alcohols and their acetates; secondary alcohols; ketones; terpenoids including squalene, phytosterols, tocopherol and amyrins; alkanes and long chain alkyl and terpenyl esters. Compositional differences which may relate to A. idaei-resistance status were noticeably higher levels of sterols, particularly cycloartenol, together with the presence of branched alkanes, and an absence of C29 ketones and the symmetrical C29 secondary alcohol in wax from the resistant cultivar Bliss. There were also differences between the cultivars in the distribution of individual amyrins and tocopherols and in the chain length distribution for homologues of fatty acids, primary alcohols and alkanes, and these may also be related to resistance to A. idaei. Emerging leaves had lower levels of primary alcohols and terpenes, but higher levels of long-chain alkyl esters, and in general, more compounds of shorter chain-length than the more mature leaves. During bioassay A. idaei displayed a preference to settle on the more mature leaves. This may be due to greater wax coverage and higher levels of the compounds of shorter chain length found in the newly emerged younger leaves at the crown of the plant.  相似文献   

10.
One new monoterpenoid glycoside (1), together with seven known compounds, including two alkaloids (23), three phenylpropanoids (46), and two nucleosides (78) were isolated from the calyces of Physalis alkekengi var. franchetii. Their structures were elucidated by a combination of detailed spectroscopic analyses, chemical methods, and comparison with reported data. These eight compounds were isolated for the first time from the genus Physalis. The chemotaxonomic significance of these compounds was summarized.  相似文献   

11.
Over 20 new strains of methane-utilizing bacteria were isolated from lake water and soil samples. Cell suspensions of these and of other known strains of methane-utilizing bacteria oxidized n-alkanes (propane, butane, pentane, hexane) to their corresponding secondary alcohols (2-propanol, 2-butanol, 2-pentanol, 2-hexanol). The product secondary alcohols accumulated extracellularly. The rate of production of secondary alcohols varied with the organism used for oxidation. The average rate of 2-propanol, 2-butanol, 2-pentanol, and 2-hexanol production was 1.5, 1.0, 0.15, and 0.08 μmol/h per 5.0 mg of protein in cell suspensions, respectively. Secondary alcohols were slowly oxidized further to the corresponding methylketones. Primary alcohols and aldehydes were also detected in low amounts (rate of production were 0.05 to 0.08 μmol/h per 5.0 mg of protein in cell suspensions) as products of n-alkane (propane and butane) oxidation. However, primary alcohols and aldehydes were rapidly metabolized further by cell suspensions. Methanol-grown cells of methane-utilizing bacteria did not oxidize n-alkanes to their corresponding secondary alcohols, indicating that the enzymatic system required for oxidation of n-alkanes was induced only during growth on methane. The optimal conditions for in vivo secondary alcohol formation from n-alkanes were investigated in Methylosinus sp. (CRL-15). The rate of 2-propanol and 2-butanol production was linear for the 40-min incubation period and increased directly with cell protein concentration up to 12 mg/ml. The optimal temperature and pH for the production of 2-propanol and 2-butanol were 40°C and pH 7.0. Metalchelating agents inhibited the production of secondary alcohols. The activities for the hydroxylation of n-alkanes in various methylotrophic bacteria were localized in the cell-free particulate fractions precipitated by centrifugation between 10,000 and 40,000 × g. Both oxygen and reduced nicotinamide adenine dinucleotide were required for hydroxylation activity. The metal-chelating agents inhibited hydroxylation of n-alkanes by the particulate fraction, indicating the involvement of a metal-containing enzyme system in the oxidation of n-alkanes. The production of 2-propanol from the corresponding n-alkane by the particulate fraction was inhibited in the presence of methane, suggesting that the subterminal hydroxylation of n-alkanes may be catalyzed by methane monooxygenase.  相似文献   

12.
Extraction, thin layer chromatography and gas chromatography–mass spectrometry of Solena amplexicaulis (Lam.) Gandhi, commonly known as creeping cucumber, (Cucurbitaceae) leaves revealed 21 long-chain primary alcohols, and 100 g leaves indicated presence of 3651.59 ± 327.18 SE µg long-chain primary alcohols. 1-Heptadecanol and 1-triacontanol were the predominant and least abundant primary alcohols, representing for 780.44 ± 42.59 and 3.28 ± 0.55 SE μg, respectively. Antibacterial property of the complete synthetic blend (0.1%), comparable to long-chain alcohols as detected by GC-FID of 100 g S. amplexicaulis leaf extracts was evaluated on the pathogenic bacteria Salmonella gallinarum by agar well diffusion method, and exhibited 20.4, 26.7 and 38.2 mm zone of inhibition at 25, 50 and 100 μl doses, respectively. One hundred µl dose of 6 individual pure synthetic compounds, 1-tridecanol, 1-pentadecanol, 1-heptadecanol, 1-nonadecanol, 1-eicosanol and 1-tricosanol comparable to the amounts present in 0.1% solution of pure isolated alcohols from S. amplexicaulis leaves displayed 16.2, 17.7, 18.6, 22.8, 15.8 and 14.5 mm zone of inhibition against this bacterium, respectively. Hundred µl dose from a synthetic blend of above 6 compounds (comparable to the proportions as present in 0.1% solution of pure isolated alcohols from 100 g S. amplexicaulis leaves) exhibited 38.1 mm zone of inhibition against this bacterium. Furthermore, 100 μl dose from a mixture (1:1) comprising of chloramphenicol (1 µg/ml) and a synthetic blend of above 6 compounds displayed 38.8 mm inhibition zone against S. gallinarum, and hence, this combination might be used against this pathogenic bacteria.  相似文献   

13.
The interaction of 1-(2-acetamido-3,4,6,-tri-O-acetyl-2-deoxy-β-D-glucopyranosyloxy)benzotriazole with primary and secondary aliphatic and cycloaliphatic alcohols or diisopropylidenegalactose in refluxing methylene chloride under the catalysis of Lewis acids resulted in alkyl-O-glucosaminides with the 1,2-trans-configuration of the glycoside bond. Other glucosaminides of substituted hydroxylamine were shown not to react under these conditions. The structures of the synthesized glucosaminides were confirmed by 1H NMR spectroscopy and comparison with the authentic compounds.  相似文献   

14.
Terpenoid emissions from ponderosa pine (Pinus ponderosa subsp. scopulorum) were measured in Colorado, USA over two growing seasons to evaluate the role of incident light, needle temperature, and stomatal conductance in controlling emissions of 2-methyl-3-buten-2-ol (MBO) and several monoterpenes. MBO was the dominant daylight terpenoid emission, comprising on average 87 % of the total flux, and diurnal variations were largely determined by light and temperature. During daytime, oxygenated monoterpenes (especially linalool) comprised up to 75 % of the total monoterpenoid flux from needles. A significant fraction of monoterpenoid emissions was dependent on light and 13CO2 labeling studies confirmed de novo production. Thus, modeling of monoterpenoid emissions required a hybrid model in which a significant fraction of emissions was dependent on both light and temperature, while the remainder was dependent on temperature alone. Experiments in which stomata were forced to close using abscisic acid demonstrated that MBO and a large fraction of the monoterpene flux, presumably linalool, could be limited at the scale of seconds to minutes by stomatal conductance. Using a previously published model of terpenoid emissions, which explicitly accounts for the physico-chemical properties of emitted compounds, we were able to simulate these observed stomatal effects, whether induced experimentally or arising under naturally fluctuation conditions of temperature and light. This study shows unequivocally that, under naturally occurring field conditions, de novo light-dependent monoterpenes comprise a significant fraction of emissions in ponderosa pine. Differences between the monoterpene composition of ambient air and needle emissions imply a significant non-needle emission source enriched in Δ-3-carene.  相似文献   

15.
Nine phenolic compounds were metabolized by the soft rot fungus Lecythophora hoffmannii via protocatechuic acid and subsequently cleaved by protocatechuate 3,4-dioxygenase as determined by oxygen uptake, substrate depletion, and ring cleavage analysis. Catechol was metabolized by catechol 1,2-dioxygenase. Fungal utilization of these aromatic compounds may be important in the metabolism of wood decay products.  相似文献   

16.
Foliar epicuticular waxes of specimens of 13 Croton species native in Brazil were extracted. The fractions containing alkanes and primary alcohols were isolated by preparative thin layer chromatography. Derivatized n-primary alcohols were identified by gas chromatography (GC) coupled with mass spectrometry and n-alkanes by GC and comparison with known standards. Relative abundances were estimated by GC coupled with flame ionization detector. The distribution of constituents of both classes was analyzed by cluster analysis, using the UPGMA method and Euclidean distances. The chemical affinities among species were compared with published data of molecular phylogenetic relationships. The distribution of n-alkanes and primary alcohols were shown to be useful markers of Croton species. Primary alcohols were more consistent than n-alkanes for species fingerprinting.  相似文献   

17.
The effect of moisture stress on monoterpenoid yield and composition of Satureja douglasii was studied under controlled conditions and in the field. Large differences in monoterpenoid yield observed among field populations were closely correlated with moisture stress. In greenhouse transplants grown under uniformly moist conditions these differences were significantly reduced. In all plants studied yield per leaf dry weight decreased with development. A growth chamber study using clones grown under different soil moisture regimes showed that high moisture stress reduced leaf weight and monoterpenoid yield per leaf, but had little effect on yield per leaf dry weight. Effects on monoterpenoid composition were less striking with high moisture stress causing a small decrease in the percentage of monoterpenoids with a p-menthane carbon skeleton and perhaps accelerating the rate of developmental conversions.  相似文献   

18.
Several radioactive analogues of abscisic acid have been tested for their growth-inhibitory effects and their metabolism in excised embryonic axes of Phaseolus vulgaris. The compounds tested were the methyl and ethyl esters of 2-14C-abscisic acid and the cis- and trans-1′,4′-diols of 2-14C-abscisic acid. All four compounds cause less growth inhibition than abscisic acid, and all four compounds are converted to abscisic acid in the axes at rates which are sufficient to account for most, if not all, of the observed growth-inhibitory activity. None of the four compounds is metabolized to the extent that abscisic acid is metabolized in the axes, suggesting that the structural requirements for growth-inhibitory activity and metabolism may be similar.  相似文献   

19.
Di-n-butyl phthalate and other dialkyl phthalates are used as carbon sources by three Nocardia sp. isolates; mono-n-butyl phthalate is used as a carbon source by an Arthrobacter sp. isolate and a Pseudomonas sp. isolate. The compounds were metabolized in these organisms by hydrolysis to the corresponding monoesters and free phthalic acid. Phthalic acid was then metabolized via protocatechuic acid by 3,4-dioxygenative ring cleavage.  相似文献   

20.
In this study a new insight was provided to understand the functions of membrane-bound alcohol dehydrogenase (mADH) and aldehyde dehydrogenase (mALDH) in the bio-oxidation of primary alcohols, diols and poly alcohols using the resting cells of Gluconobacter oxydans DSM 2003 and its mutant strains as catalyst. The results demonstrated that though both mADH and mALDH participated in most of the oxidation of alcohols to their corresponding acid, the exact roles of these enzymes in each reaction might be different. For example, mADH played a key role in the oxidation of diols to its corresponding organic acid in G. oxydans, but it was dispensable when the primary alcohols were used as substrates. In contrast to mADH, mALDH appears to play a relatively minor role in organic acid-producing reactions because of the possible presence of other isoenzymes. Aldehydes were, however, found to be accumulated in the mALDH-deficient strain during the oxidation of alcohols.  相似文献   

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