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1.
Paula Guedes de Pinho Patrícia Valentão Rui F. Gonçalves Carla Sousa Paula B. Andrade 《Rapid communications in mass spectrometry : RCM》2009,23(15):2292-2300
Volatile and semi‐volatile components of internal and external leaves of Brassica oleracea L. var. costata DC, grown under different fertilization regimens, were determined by headspace solid‐phase microextraction (HS‐SPME) combined with gas chromatography/ion trap mass spectrometry (GC/ITMS). Forty‐one volatiles and non‐volatile components were formally identified and thirty others were tentatively identified. Qualitative and quantitative differences were noticed between internal and external leaves. In general, internal leaves exhibited more aldehydes and sulfur volatile compounds than external ones, and less ketone, terpenes and norisoprenoid compounds. The fertilization regimens influenced considerably the volatile profile. Fertilizations with higher levels of sulfur produced Brassica leaves with more sulfur volatiles. In opposition, N and S fertilization led to leaves with lower levels of norisoprenoids and terpenes. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
2.
Hye-Young Seo Jun-Hyoung Kim Hyun-Pa Song Dong-Ho Kim Myung-Woo Byun Joog-Ho Kwon Kyong-Su Kim 《Radiation Physics and Chemistry》2007,76(11-12):1869-1874
The study was carried out to determine the effects of gamma irradiation on the volatile flavor components including essential oils, of Angelica gigas Nakai. The volatile organic compounds from non- and irradiated A. gigas Nakai at doses of 1, 3, 5, 10 and 20 kGy were extracted by a simultaneous steam distillation and extraction (SDE) method and identified by GC/MS analysis. A total of 116 compounds were identified and quantified from non- and irradiated A. gigas Nakai. The major volatile compounds were identified 2,4,6-trimethyl heptane, α-pinene, camphene, α-limonene, β-eudesmol, α-murrolene and sphatulenol. Among these compounds, the amount of essential oils in non-irradiated sample were 77.13%, and the irradiated samples at doses of 1, 3, 5, 10 and 20 kGy were 84.98%, 83.70%, 83.94%, 82.84% and 82.58%, respectively. Oxygenated terpenes such as β-eudesmol, α-eudesmol, and verbenone were increased after irradiation but did not correlate with the irradiation dose. The yields of active substances such as essential oil were increased after irradiation; however, the yields of essential oils and the irradiation dose were not correlated. Thus, the profile of composition volatiles of A. gigas Nakai did not change with irradiation. 相似文献
3.
4.
Fátima Fernandes Paula Guedes de Pinho José A. Pereira Paula B. Andrade 《Microchemical Journal》2009,93(1):99-109
In this work, the evolution of the qualitative and quantitative profile of the volatile fraction of Pieris brassicae after feeding on Brassica oleracea var. acephala (kale) was monitored through time. HS-SPME/GC-MS was applied to both the host plant and the living insect and its excrements. A total of seventy seven compounds (lipoxygenase pathway by-products, nitrogen compounds, norisoprenoids, sulphur compounds, terpenes, among others) were identified. Thirty eight compounds were identified in insect after 2 h of starvation and forty eight compounds in excrements. Qualitative and quantitative changes were detected along time. Dimethyldisulfide, dimethyltrisulfide, limonene and eugenol were major compounds for all analysed times in both matrices, being limonene an important compound in insect after starvation. The accumulation by P. brassicae of some compounds, such as limonene, was verified, suggesting a mechanism by which the insect can take benefit from bioactive constituents from the diet. Along with accumulation, complete excretion of some compounds, including nitrogen bearing compounds, by-products of glucosinolates was detected. These results reflect one of the strategies used to overcome plant barriers, namely detoxification of toxic compounds. The findings contribute to the knowledge of the metabolization of the volatile compounds in insects and contribute to the body of knowledge of this ecologic system. 相似文献
5.
V. I. Grishkovets D. A. Panov E. A. Palii V. V. Kachala A. S. Shashkov 《Chemistry of Natural Compounds》2005,41(3):326-331
The new caffeylated triterpene glycosides hederagenin 3-O-(6-O-caffeyl-β-D-glucopyranosyl)-(1→4)-O-β-D-xylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-β-L-arabinopyranoside and its 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl and 28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl esters were isolated from leaves of Kalopanax septemlobum var. maximowiczii introduced in Crimea. The structures of these compounds were established using chemical methods and NMR spectroscopy.__________Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 263–267, May–June, 2005. 相似文献
6.
Alaize de P. Martins A. A. Craveiro M. I. L. Machado Fernanda N. Raffin T. F. Moura Cs. Novák Zsuzsanna éhen 《Journal of Thermal Analysis and Calorimetry》2007,88(2):363-371
Inclusion complex between the essential oil
of Mentha x villosa Hudson and β-cyclodextrin,
with a 1:9 mass/mass oil–β-cyclodextrin ratio was prepared by co-precipitation
and kneading methods in a hydroethanolic medium. The GC/MS analysis showed
a total volatile content of 99.5% in the Mentha x
villosa oil. The characterization of the complex involved the analysis
of the original essential oil, the surface and the total extracted oils. Among
28 detected compounds in the original essential oil, 13 are monoterpenes and
10 sesquiterpenes, furthermore, piperitenone-oxide is the major component
(35.4%). 12 compounds were totally and 11 partially complexed, 3 have been
adsorbed only on the surface of the β-CD and 2 have not been detected
neither in the surface oil nor in the complexed oil. A 13.6% encapsulation
efficiency was observed, while the total oil and volatiles retention was 15
and 77%, respectively. Non-parametric statistic analysis of the data showed
that the profile of the volatiles were not significantly different comparing
the original oil and the complexed oil (p>0.04).
The results of thermogravimetry-mass spectrometry and XRD analysis have proven
the inclusion complex formation between the essential oil and cyclodextrin. 相似文献
7.
Mohammad A. Bigdeli Shahram Moradi Firouzeh Nemati 《Journal of Molecular Structure》2008,860(1-3):64-79
Ab initio calculation at HF/6-31G* and MP2/6-31G* levels of theory for geometry optimization of some syn- and anti-1,8-di-pyridine 9H-fluorene, dibenzo[b,d]furan, 9H-carbazole and Dibenzo[b,d]thiophene are reported. The rotational barrier energy, heat of formation and Gibbs energy are determined for the conversion of the anti-(syn) to the syn (anti)-isomers at 25 °C in the gas phase. The models are chosen as isomers of 9H-fluorene, dibenzo[b,d]furan, 9H-carbazole and dibenzo[b,d]thiophene as scaffold with pyridine as module. Results obtained show that (at equilibrium) for most of atropisomers the syn- is favored over the anti-isomer. Moreover, the ground state structures show that the modules are not parallel to each other but are tilted away in order to increase separation and there by minimize electrostatic repulsion. In atropisomers of 9H-carbazole the isomers are showing an attraction due to the presence of nitrogen atom. Influence of the position of nitrogen atom on the magnitude of the rotational barriers in these atropisomers is also studied. 相似文献
8.
Huanhuan Qu Baixue Li Xu Li Guangzhong Tu Juan Lü Wenji Sun 《Microchemical Journal》2008,89(2):159-164
A high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) analytical method was developed to simultaneously detect and quantify three main distinctive compounds (forsythiaside, rutin and forsythin) in different parts of Forsythia suspensa (F. suspensa), an herbal medicine. This was the first report on the quantification of bioactive constituents in different parts of F. suspensa by HPLC-ESI-MS analytical method. The calibration curves of the three compounds showed good linearity (R2 > 0.9994). The method was reproducible with intra- and inter-day variation less than 1.35% and 2.00%, respectively. The recovery of the assay was in the range of 98.27–101.07%. The results indicated that the developed assay could be considered as a suitable quality control method for this commonly used herbal medicine. 相似文献
9.
Determination of volatile compounds in foliage of Fraser fir (Abies fraseri) and balsam fir (Abies balsamea) 总被引:1,自引:1,他引:0
Samantha J. Carlow Lauren Ayers Andy Bailey Betsy John Allyson Richardson Brad Shepherd Royce S. Woosley David J. Butcher 《Microchemical Journal》2006,83(2):91-97
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
10.
Hong Mei Li Wei Guang Wang Xiao Nian Li Yong Zhao Rong Tao Li Han Dong Sun 《中国化学快报》2008,19(12):1450-1452
A new cinnamic acid monoterpenoid ester, intermedin C (1), was isolated from the aerial parts of Schisandra propinqua var. interthedia. The structure of 1 was elucidated by spectroscopic methods including extensive ^1D and 2D NMR techniques. 相似文献
11.
Li-Gen Lin Henry Pak-Ho Leung Jian-Yu Zhu Chun-Ping Tang Chang-Qiang Ke John A. Rudd Ge Lin Yang Ye 《Tetrahedron》2008,64(44):10155-10161
Three new croomine-type Stemona alkaloids, tuberocrooline (1), 10-hydroxycroomine (2), and dehydrocroomine (3), and four new tuberostemonine-type alkaloids, tuberostemoline (4), tridehydrotuberostemonine (5), 9α-bisdehydrotuberostemonine (6), and 9α-bisdehydrotuberostemonine A (7), along with ten known constituents, were isolated from the roots of Stemona tuberosa collected from Yunnan province. The structures of the new compounds were established on the basis of one- and two-dimensional NMR spectra and other spectroscopic studies. The antitussive activity of the major alkaloids was tested using the citric acid-induced guinea pig cough model. Croomine (8) exhibited a dose-dependent inhibition of coughing with an ID50 value of 0.18 mmol/kg. 相似文献
12.
Marta Francisco Diego A. Moreno María Elena Cartea Federico Ferreres Cristina García-Viguera Pablo Velasco 《Journal of chromatography. A》2009,1216(38):6611-6619
Brassica raparapa group is widely distributed and consumed in northwestern Spain. The consumption of Brassica vegetables has been related to human health due to their phytochemicals, such as glucosinolates and phenolic compounds that induce a variety of physiological functions including antioxidant activity, enzymes regulation and apoptosis control and the cell cycle. For first time in Brassica crops, intact glucosinolates and phenolic compounds were simultaneously identified and characterized. Twelve intact glucosinolates, belonging to the three chemical classes, and more than 30 phenolic compounds were found in B. rapa leaves and young shoots (turnip greens and turnip tops) by LC–UV photodiode array detection (PAD)–electrospray ionization (ESI). The main naturally occurring phenolic compounds identified were flavonoids and derivatives of hydroxycinnamic acids. The majority of the flavonoids were kaempferol, quercetin and isorhamnetin glycosylated and acylated with different hydroxycinnamic acids. Quantification of the main compounds by HPLC-PAD showed significant differences for most of compounds between plant organs. Total glucosinolate content value was 26.84 μmol g−1 dw for turnip greens and 29.11 μmol g−1 dw for turnip tops; gluconapin being the predominant glucosinolate (23.2 μmol g−1 dw). Phenolic compounds were higher in turnip greens 51.71 μmol g−1 dw than in turnip tops 38.99 μmol g−1 dw, in which flavonols were always the major compounds. 相似文献
13.
Ju-Woon Lee Sang-Hee Oh Eui-Baek Byun Jae-Hun Kim Jang-Ho Kim Jae-Ho Woon Myung-Woo Byun 《Radiation Physics and Chemistry》2007,76(11-12):1858-1861
Enterobacter sakazakii has been implicated as a causal organism in a severe form of neonatal meningitis, with reported mortality rates of 20%. The population at greatest risk is immunocompromised infants of any age. Dried infant formula has been identified as a potential source of the organism in both outbreaks and sporadic cases. The objective of this study was to investigate theirradiation effect of the inactivation on E. sakazakii (ATCC 29544) of a dehydrated infant formula. The D10-values were 0.22–0.27 and 0.76 kGy for broth and dehydrated infant formula, respectively. The irradiation at 5.0 kGy was able to completely eliminate the E. sakazakii inoculated at 8.0 to 9.0 log CFU g−1 onto a dehydrated infant formula. There was no regrowth for all samples during the time they were stored at 10 °C for 6 h after rehydration. The present results indicated that a gamma-irradiation could potentially be used to inactivate E. sakazakii in a dehydrated powdered infant formula. 相似文献
14.
V. I. Grishkovets D. A. Panov V. V. Kachala A. S. Shashkov 《Chemistry of Natural Compounds》2005,41(2):194-199
Eight known glycosides of hederagenin and the new triterpene glycoside 3-O-β-D-xylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin were isolated by chromatographic methods from leaves of Kalopanax septemlobum var. maximowichii introduced to Crimea. The known 3-O-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin was observed for the first time in Kalopanax septemlobum.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 156–159, March–April, 2005. 相似文献
15.
1,10-Phenanthrolinium N-ylides,can react with malonitrile and aromatic aldehydes via a domino-Knoevenagel cyclization to afford a new class of trihydropyrrolo[1,2-a][l,10]phenanthroline derivatives as stable helical compounds in a simple,mild,and efficient protocol in excellent yields. 相似文献
16.
The continuous chemical investigation on the ethyl acetate (EtOAc) soluble fraction of the MeOH extract afforded two new lanostane triterpenoid derivatives including one with a rearranged lanostane skeleton. They were identified as 3,4-seco-8-(14→13R)abeo-17,13-friedo-9β-lanosta-4(28), 7,14(30),24-tetraen-26,23-olide-23-hydroxy-3-oic acid (1) and 7,14-mariesa- dien-3oL-hydroxy-25-methoxy-26-oic acid (2). Structural determination of these compounds were carried out by the spectral studies especially by the two digital (2D)-NMR and high-resolution MS experiences. 相似文献
17.
Marcos Taveira 《Microchemical Journal》2009,93(1):67-557
The volatile compounds of Rumexinduratus leaves were studied for the first time. In order to achieve the most complete volatile profile four different extractive techniques (hydrodistillation, solid-phase microextraction, Soxhlet system and direct solvent extraction) were applied. The different extracts were analysed by gas chromatography/ion trap-mass spectrometry (GC/IT-MS) which allowed the identification of 81 compounds, distributed by several chemical classes: esters, terpenes, aldehydes, acids, norisoprenoids, ketones, naphthalene derivatives, steroids derivatives and alcohols, among others. The different techniques lead to different compounds' extraction. Using hexane and dichloromethane, 9 and 4 compounds were extracted, respectively. Hydrodistillation, solid-phase microextraction and Soxhlet extraction allowed the extraction of 43, 24 and 29 compounds, respectively. Hydrodistillation was revealed to be the most effective technique, allowing the extraction of a higher number of compounds, both in the hydrolat (20 compounds) and essential oil (34 compounds), having 11 compounds in common. 相似文献
18.
Ce Lβ emission spectra of CeF3 and CeO2 have been measured with energy resolution of ~ 3 eV by a wave-dispersive spectrometer. The observed Ce Lβ7 band shows certain difference between the two compounds both in profile and intensity. The chemical effects can be reproduced by a band calculation using WIEN2k, which suggests that the Ce Lβ7 reflects valence-band structure of compounds, and therefore, is hopeful as a probe of selective X-ray absorption fine structure. 相似文献
19.
Young-hee Kim Paul A Cooke Robert Greatrex John D Kennedy Mark Thornton-Pett 《Journal of organometallic chemistry》1998,550(1-2)
[7,7-(PMe2Ph)2-9-(η6-isoPrC6H4Me)-7,9-PtRuB9H11] has a formal closo Wadian cluster-electron count, but a nido geometry, whereas [1-(η6-isoPrC6H4Me)-4,4-(PMe2Ph)2-1-4-RuPtB9H9], which does have a closo geometry, has a formal sub-closo cluster electron count; both compounds are formed in the reaction between [6-(η6-isoPrC6H4Me)-nido-6 RuB9H13], KH and [PtCl2(PMe2Ph)2]. 相似文献
20.
Friedrich Asinger Alfons Saus Magdalena von Wachtendonk 《Monatshefte für Chemie / Chemical Monthly》1980,111(2):385-398
Thiomorpholine as well as alkyl substituted thiomorpholines and their Sdioxides, respectively, are transformed into the corresponding N-Aminothiomorpholines by nitrosation (1–5) followed by the reduction with zinc in acetic acid/acetic acid anhydride under simultaneous formation of the corresponding N-acetyl derivates, and hydrolysis by hydrochloric acid (6–9). Examples of this method are described. 4-Aminothiomorpholines and their Sdioxides react with aldehydes or ketones to give azomethines (10–31). Acylation with mono-and dicarbonic acid chlorides leads to the N-acyl derivatives32–44.Mannich condensation is also possible. By oxidation with yellow mercury oxide tetracenes are formed (46–47).
Teil der DissertationM. Schmitz, Techn. Hochschule Aachen, 1975. 相似文献