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1.
Planta Med ; 80(13): 1079-87, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25127023

RESUMO

Artemisia species possess pharmacological properties that are used for medical purposes worldwide. In this paper, the essential oils from the aerial parts of Artemisia nilagirica and Artemisia maritima from the western Indian Himalaya region are described. The main compounds analyzed by simultaneous GC/MS and GC/FID were camphor and 1,8-cineole from A. maritima, and camphor and artemisia ketone from A. nilagirica. Additionally, the oils were evaluated for their antibacterial, antifungal, mosquito biting deterrent, and larvicidal activities. A. nilagirica essential oil demonstrated nonselective antifungal activity against plant pathogens Colletotrichum acutatum, Colletotrichum fragariae, and Colletotrichum gloeosporioides, whereas A. maritima did not show antifungal activity. Both Artemisia spp. exhibited considerable mosquito biting deterrence, whereas only A. nilagirica showed larvicidal activity against Aedes aegypti. Antibacterial effects assessed by an agar dilution assay demonstrated greater activity of A. maritima essential oil against Staphylococcus aureus and Pseudomonas aeruginosa compared to A. nilagirica.


Assuntos
Antifúngicos/farmacologia , Artemisia/química , Cânfora/farmacologia , Cicloexanóis/farmacologia , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Aedes/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antifúngicos/isolamento & purificação , Cânfora/química , Cânfora/isolamento & purificação , Cicloexanóis/química , Cicloexanóis/isolamento & purificação , Eucaliptol , Cromatografia Gasosa-Espectrometria de Massas , Índia , Repelentes de Insetos/química , Repelentes de Insetos/isolamento & purificação , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Monoterpenos/química , Monoterpenos/isolamento & purificação , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
2.
Nat Prod Commun ; 12(4): 611-614, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30520607

RESUMO

This work aims to elucidate the chemical composition of two essential oil (EO) samples obtained from the leaves of Thymus vulgaris L. (Lamiaceae) collected in two regions of Northwestern Algeria (Tlemcen and Mostaganem) and to assess their in vivo acute toxicity and anti-inflammatory activity. Sixty-six compounds could be identified by means of simultaneous GC-FID and GC-MS, accounting for 99.3% of total thyme oil of Mostaganem (EO.TM) and 99.0% of Tlemcen (EO.TT). In both samples, thymol was the major component, amounting to 59.5% (EO.TM) and 67.3% (EO.TT) of the total oil. EO.TT proved to be acutely toxic to mice at a dose of 4500 mg/kg p.o., whereas EO.TM did not show signs of acute toxicity, even at the highest dose tested (5000 mg/kg p.o.). Both EO samples were proven to possess anti-inflammatory activities, significantly reducing carrageenan-induced paw edema in mice (after 6 hours at a dose -of 400 mg/kg p.o) at 58.4% for EO.TT and 50.4% for EO.TM, respectively. In conclusion, it could be demonstrated that EOs of T. vulgaris exhibit a considerable in vivo anti-inflammatory activity at non-toxic doses.


Assuntos
Anti-Inflamatórios/química , Edema/tratamento farmacológico , Óleos Voláteis/química , Óleos de Plantas/química , Thymus (Planta)/química , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Edema/imunologia , Feminino , Humanos , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Óleos Voláteis/administração & dosagem , Óleos Voláteis/isolamento & purificação , Folhas de Planta/química , Óleos de Plantas/administração & dosagem , Óleos de Plantas/isolamento & purificação
3.
Biochimie ; 88(7): 785-91, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16488068

RESUMO

Hypochlorite (HOCl) attacks amino acid residues in LDL making the particle atherogenic. Tryptophan is prone to free radical reactions and modification by HOCl. We hypothesized, that free tryptophan may quench the HOCl attack therefore protecting LDL. Free tryptophan inhibits LDL apoprotein modification and lipid oxidation. Tryptophan-HOCl metabolites associate with LDL reducing its oxidizability initiated by endothelial cells, Cu(2+) and peroxyl radicals. One tryptophan-HOCl metabolite was identified as 4-methyl-carbostyril which showed antioxidative activity when present during Cu(2+) mediated lipid oxidation, but did not associate with LDL. Indole-3-acetaldehyde, a decomposition product of tryptophan chloramine (the product of the tryptophan-HOCl reaction) was found to associate with LDL increasing its resistance to oxidation. Myeloperoxidase treatment of LDL in the presence of chloride, H(2)O(2) and tryptophan protected the lipoprotein from subsequent cell-mediated oxidation. We conclude that, in vivo, the activated myeloperoxidase system can generate antioxidative metabolites from tryptophan by the reaction of hypochlorite with this essential amino acid.


Assuntos
Ácido Hipocloroso/química , Lipoproteínas LDL/metabolismo , Triptofano/química , Acetaldeído/análogos & derivados , Acetaldeído/farmacologia , Células Cultivadas , Cobre/farmacologia , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Hidroxiquinolinas/farmacologia , Ácido Hipocloroso/metabolismo , Ácido Hipocloroso/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Quinolonas/farmacologia , Triptofano/metabolismo , Triptofano/farmacologia
4.
J Agric Food Chem ; 54(17): 6303-7, 2006 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-16910723

RESUMO

The antioxidant activity of a commercial rectified clove leaf essential oil (Eugenia caryophyllus) and its main constituent eugenol was tested. This essential oil comprises in total 23 identified constituents, among them eugenol (76.8%), followed by beta-caryophyllene (17.4%), alpha-humulene (2.1%), and eugenyl acetate (1.2%) as the main components. The essential oil from clove demonstrated scavenging activity against the 2,2-diphenyl-1-picryl hydracyl (DPPH) radical at concentrations lower than the concentrations of eugenol, butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA). This essential oil also showed a significant inhibitory effect against hydroxyl radicals and acted as an iron chelator. With respect to the lipid peroxidation, the inhibitory activity of clove oil determined using a linoleic acid emulsion system indicated a higher antioxidant activity than the standard BHT.


Assuntos
Antioxidantes/farmacologia , Eugenol/análise , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Folhas de Planta/química , Syzygium/química , Compostos de Bifenilo , Hidroxianisol Butilado , Hidroxitolueno Butilado , Sequestradores de Radicais Livres , Ácido Linoleico/química , Sesquiterpenos Monocíclicos , Picratos , Sesquiterpenos Policíclicos , Sesquiterpenos/análise , Substâncias Reativas com Ácido Tiobarbitúrico/análise
5.
Nat Prod Res ; 20(6): 593-7, 2006 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-16835093

RESUMO

A new phthalic acid ester 1,2-benzenedicarboxylic acid bis(2S-methyl heptyl) ester (1) was isolated from the hexane extract of the whole plant of Ajuga bracteosa. In addition, chloroform and methanol extracts yielded neo-clerodane diterpene ajugarin-I and two iridoid glycosides, reptoside and 8-O-acetyl harpagide. The structures of all the compounds were confirmed by extensive spectroscopic analysis. From the two oily fractions nine and six volatile constituents respectively were identified by GCMS. Linalyl acetate was found to be common in both the oil fractions. This plant is a new source of linalyl acetate, a valuable perfumery compound.


Assuntos
Ajuga/química , Ésteres/isolamento & purificação , Ácidos Ftálicos/isolamento & purificação , Diterpenos/isolamento & purificação , Ésteres/química , Cromatografia Gasosa-Espectrometria de Massas , Glicosídeos/química , Glicosídeos/isolamento & purificação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Ácidos Ftálicos/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho
6.
Nat Prod Commun ; 11(4): 519-22, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27396209

RESUMO

The essential oils of Juniperus phoenicea L. from Algeria were obtained by hydrodistillation and analyzed by GC-FID and GC-MS. Concerning their chemical composition, 74, 61 and 72 volatile compounds were identified from fresh leaves, dried leaves and berries, representing 88.8%, 91.3% and 94.7% of the total composition, respectively. The main monoterpene in the oils of fresh leaves, dried leaves and berries was a-pinene (29.6% / 55.9% / 56.6%), accompanied by lesser amounts of the sesquiterpenes ß-caryophyllene (2.6% / 1.6% /1.2%) and germacrene D (2.01% / 1.7% / 1.5%), respectively. Antibacterial activity of J. phoenicea essential oils was tested against one Gram-negative and four Gram-positive bacterial strains and the yeast Candida albicans, responsible for nosocomial infections. As references, 14 antibiotics and 5 antifungal agents were evaluated. The berry essential oil was ineffective against all but two of the strains tested, whereas the essential oil of dried leaves significantly inhibited all strains but Pseudomonas aeruginosa, which turned out to be the most resistant strain overall. However, Escherichia coli was the most susceptible to the essential oils tested. The essential oil of dry leaves was highly active against Candida albicans, outclassing even the standard antifungal substances. These promising results could substantiate the use of essential oils in the treatment of hospital-acquired infections.


Assuntos
Anti-Infecciosos/análise , Juniperus/química , Óleos Voláteis/química , Testes de Sensibilidade Microbiana
7.
Nat Prod Commun ; 11(10): 1551-1554, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30549620

RESUMO

The present study evaluates the chemical composition and olfactory description of the essential oils of Asarum glabrum Merr., Calocedrs macrolepis Kurz, Cunninghamia lanceolata (Lamb.) Hook. and Glyptostrobus pensilis (Stainton ex D.Don) K. Koch. The essential oils were obtained by hydrodistillation in a Clevenger-type apparatus and analyzed by GC-FID and GC-MS. Concerning their chemical composition, 66, 42, 57 and 21 volatile compounds were identified from dried leaves in the case of Asarum glabrum Merr. and wood for the other three, representing 98.7%, 67.2%,,92.0% and 87.5 % of the total composition, respectively. The main compounds of Asarum glabrum oil were safrole (38.1%), apiole (10.8%) and myristicin (8.0%); of Calocedrus macrolepis verbenone (9.3%), piperitone (8.6 %), a-terpineol (6.0%) and (Z)-p-terpineol (5.3%); of Cunninghamia lanceolata oil cedrol (26.3%), a-terpineol (24.1%) and camphor (7.0%); and of Glyptostrobus pensilis oil dihydro-eudesmol isomer (assumed) (18.3%), cedrol (16.4%), occidentalol (13.2%) and elemol (9.0%).


Assuntos
Odorantes/análise , Óleos Voláteis/análise , Destilação , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Plantas/química , Vietnã
8.
Nat Prod Commun ; 11(11): 1697-1700, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30475510

RESUMO

The seed oils of twenty-six species of Apiaceae belonging to the genera Bunium, Cnidium, Ferula, Ferulago, Heracleum, Hippomarathrum, Malabaila, Myrrhoides, Olymposciadium, Pimpinella, Prangos, Szovitsia, Trigonasciadium, Trinia and Zosima, collected in Turkey, were investigated for their oil content, and amount of petroselinic acid (PA), as well as for the composition of their fatty acid methyl esters (FAMEs) by GC-MS. Seed oil content ranged from 7.1% in Szovitsia callicarpa to 29.3% in Ferda haussknechtii. The results showed that the seed oils of the studied species contained high amounts of PA (1.2-72.2%), followed by significant amounts of linoleic (LA, 13.8-50.8%) and oleic (OA, 4.2-61.6%) acids. PA was found in all the analyzed species, except for Olymposciadium caespitosum, which belongs to a monotypic endemic genus of the family. According to data from our study, PA was found to be predominantly in the seed oils of Hippomarathrum cristatum (72.2%), Trinia glauca (64.9%) and Bunium microcarpum (59.7%) and, therefore these species might be considered as new sources of PA, and represent a potential oleochemical raw material. This is the first extensive study of the composition ofTurkish Apiaceae species. The high amounts of PA may also have chemotaxonomic significance.


Assuntos
Apiaceae/química , Ácidos Graxos/química , Ácidos Oleicos/química , Óleos de Plantas/química , Sementes/química , Turquia
9.
Nat Prod Commun ; 11(11): 1701-1703, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30475511

RESUMO

Cinnamomum rigidifolium, Dasymaschalon longiusculum, Fissistigma maclurei and Goniothalamus albiflorus were collected from different landscapes in Vietnam and hydro distilled to produce essential oils with yields from 0.15 - 0.35%. The oils were analyzed by GC-MS-FID and rechecked by measurements on two different instrumentation configurations. The main components of the studied essential oils were for Cinnamomum rigidifolium linalool (19.4%), α-pinene (13.8%), verbenone (9.9%) and cis-verbenol (8.9%), total identified 90.5%; for Dasymaschalon longiusculum spathulenol (21.4%), caryophyllene oxide (17.6%), a-pinene (5.5%) and ß-pinene (5.2%), total identified 70.1%; for Fissistigma maclurei spathulenol (17.8%), guaia-6,10(14)-diene-40-ol (10.3%), (E)-ß-caryophyllene (7.3%) and caryophyllene oxide (7.0%), total identified 75.3% and for Goniothalamus albiflorus 1,8-cineole (13.2%), α-pinene (10.6%), ledol (7.5%) and caryophyllene oxide (7.3%), total identified 78.0%.


Assuntos
Annonaceae/química , Cinnamomum/química , Óleos Voláteis/química , Óleos de Plantas/química , Vietnã
10.
Nat Prod Commun ; 11(11): 1717-1720, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30475515

RESUMO

The chemical composition, antioxidant, antimicrobial and insecticidal properties of essential oil obtained by hydro-distillation from Bubonium imbricatum Cav. have been investigated. The essential oil of aerial parts was analyzed by GC-FID and GC-MS. A total of 63 compounds were identified representing more than 82% of the oil. The major components were cis-chrysanthenyl acetate (31.2%) and thymol isobutyrate (3.4%). The antioxidant activity was evaluated by the DPPH and reducing power test. The data showed moderate activity compared with the reference compounds. Our results showed strong activity of the investigated oil against all tested microorganisms. The highest antibacterial activity was observed against Bacillus subtilis (inhibition zone= 18 ± 0.21, MIC= 0.18 mg/mL). In general, Gram-positive bacteria were more susceptible than Gram-negative ones. Candida parapsilosis was the most sensitive among the Candida strains tested. LD50 and LD90 values were 33.1 and 53.1 ppm against 1-d-old larvae of Aedes aegypti L.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Asteraceae/química , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Aedes/efeitos dos fármacos , Animais , Anti-Infecciosos/química , Antioxidantes/química , Bactérias/efeitos dos fármacos , Bioensaio , Candida/efeitos dos fármacos , Inseticidas/química , Larva/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Marrocos , Óleos Voláteis/química , Óleos de Plantas/química
11.
Nat Prod Commun ; 10(1): 139-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25920236

RESUMO

The polar and apolar fractions of Curcuma longa and C. zanthorriza enriched by ar-turmerone, ar-curcumene and xanthorrizol were screened for cytotoxic activity against the HeLa cell line. Actinomycin D and curcumin were used as reference samples, both known for their cytotoxic properties. Amongst all fractions tested, the xanthorrizol fraction (CC50: 26.1 ± 1.9 µM) showed the strongest cytotoxic properties similar to those of curcumin (CC50: 8.1 ± 1.7 µM). Further studies also revealed that the cytotoxic effects of the extracts and pure compounds are caused by apoptosis induction identified by the cleaved form of PARP protein.


Assuntos
Antineoplásicos Fitogênicos/análise , Curcuma/química , Óleos Voláteis/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos
12.
Nat Prod Commun ; 10(6): 1085-90, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26197557

RESUMO

In the present study, the chemical composition and antioxidant potential of an essential oil of ginger rhizomes from Ecuador was elucidated. The analysis of the essential oil by GC/FID/MS resulted in identification of 71 compounds, of which the main are citral (geranial 10.5% and neral 9.1%), α-zingiberene (17.4%), camphene (7.8%), α-farnesene (6.8%) and ß-sesquiphellandrene (6.7%). The in vitro antioxidant activity of the essential oil expressed by IC50 in descending order is: hydroxyl radical (OH*) scavenging (0.0065 µg/mL) > chelating capacity (0.822 µg/mL) > 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical cation (ABTS*+) scavenging (3.94 µg/mL) > xanthine oxidase inhibition (138.0 µg/mL) > oxygen radical (O2*) scavenging (404.0 µg/mL) > 2,2- diphenyl-1-picrylhydrazyl radical (DPPH*) scavenging (675 µg/mL). Lipid peroxidation inhibition of the essential oil was less efficient than butylhydroxytoluol (BHT) in both stages, i.e. hydroperoxide and malondialdehyde formation. In vivo studies in Saccharomyces cerevisiae demonstrated a significant dose-dependent increase in antioxidant marker enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), blocking the oxidation processes in yeast cells. Moreover, ginger essential oil in concentrations of 1.6 mg/mL increases the viability of cells to oxidative stress induced by H2O2.


Assuntos
Antioxidantes/química , Óleos Voláteis/química , Extratos Vegetais/química , Zingiber officinale/química , Antioxidantes/isolamento & purificação , Catalase/metabolismo , Equador , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Superóxido Dismutase/metabolismo
13.
Nat Prod Commun ; 10(6): 1071-4, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26197554

RESUMO

The Himalayan region is very rich in a great variety of medicinal plants. In this investigation the essential oils of two selected species are described for their antimicrobial and larvicidal as well as biting deterrent activities. Additionally, the odors are characterized. Analyzed by simultaneous GC-MS and GC-FID, the essential oils' chemical compositions are given. The main components of Skimmia laureola oil were linalool and linalyl acetate whereas sabinene was found as the main compound for Juniperus macropoda essential oil. Antibacterial testing by agar dilution assay revealed highest activity of S. laureola oil against all tested bacteria, followed by J. macropoda oil. Antifungal activity was evaluated against the strawberry anthracnose causing plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides. Juniperus macropoda essential oil indicated higher antifungal activity against all three pathogens than S. laureola oil. Both essential oils showed biting deterrent activity above solvent control but low larvicidal activity.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Juniperus/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Rutaceae/química , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Testes de Sensibilidade Microbiana
14.
Nat Prod Commun ; 10(1): 133-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25920235

RESUMO

The essential oils of two representatives of the Lamiaceae, Dracocephalum heterophyllum Benth. and Hyssopus officinalis L., are described for their antifungal, antibacterial, larvicidal and inect biting deterrent activities. Additionally, the chemical compositions of the essential oils, analyzed by simultaneous GC-MS and GC-FID, and odor descriptions are given. The main components of H. officinalis oil were pinocarvone, cis-pinocamphone, and ß-pinene. Citronellol was found as the main compound of D. heterophyllum essential oil. Antibacterial testing by agar dilution assay revealed greater activity of D. heterophyllum against Staphylococcus aureus compared with H. officinalis. D. heterophyllum essential oil also showed promising antifungal activity against Colletotrichum species and was more toxic to Aedes aegypti larvae in a larvicial bioassay. Both essential oils showed high activity in the biting deterrent bioassay.


Assuntos
Antibacterianos/análise , Antifúngicos/análise , Repelentes de Insetos/análise , Lamiaceae/química , Óleos Voláteis/química , Aedes , Animais , Ásia , Testes de Sensibilidade Microbiana
15.
Nat Prod Commun ; 10(1): 143-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25920237

RESUMO

Nerolidol and its derivatives, namely cis-nerolidol, O-methyl-nerolidol, O-ethyl-nerolidol, (-)-α-bisabolol, trans,trans-farnesol and its main natural source cabreuva essential oil, were tested for their antimicrobial activity against airborne microbes and antifungal properties against plant pathogens. Among the tested compounds, α-bisabolol was the most effective antimicrobial agent and trans,trans-farnesol showed the best antifungal activity.


Assuntos
Microbiologia do Ar , Anti-Infecciosos/análise , Sesquiterpenos/química , Fabaceae , Testes de Sensibilidade Microbiana , Óleos Voláteis
16.
Nat Prod Commun ; 10(1): 149-51, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25920238

RESUMO

In the present study, the chemical composition of the essential oil obtained from the aerial parts of Aaronsohnia pubescens (Desf.) K.Bremer & Humphries (Asteraceae), a chamomile-like medicinal plant, was studied. Using both GC-MS and GC-FID methods, 58 volatile compounds could be identified representing 96.6% of the total essential oil composition. The main compounds in the essential oil were monoterpene hydrocarbons such as (Z)-ß-ocimene (53.8%), myrcene (15.2%) and α-pinene (7.7%). Moreover, the essential oil of A. pubescens was tested for its antifungal activity against seven strains of phytopathogenic fungi , i.e. Aspergillus niger, A. flavus, Penicillium purpurogenum, P. jensenii, P. expansum, and Fusarium oxysporum f.sp. albedinis, using the disc diffusion method. With the exception of P. jensenii, A. pubescens essential oil demonstrated a considerable antifungal activity against all tested strains. The present results confirm the traditional use of A. pubescens as a food preservative.


Assuntos
Antifúngicos/análise , Matricaria/química , Óleos Voláteis/química , Argélia , Testes de Sensibilidade Microbiana
17.
Phytochemistry ; 61(8): 923-6, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12453518

RESUMO

Six novel alkylated p-Benzoquinones irisoquin (A-F) (1-2, 4-7) together with a known cytotoxic quinone, irisoquin (3) along with three known isoflavones, tectoregenin, iristectorin and irigenin were isolated from the rhizomes of Iris kumaonensis and characterized. The structures of compounds 1-2, 4-7 were confirmed by extensive spectroscopic analysis, IR, MS, HRMS, GC, GC-MS, 1D (1H, 13C, NOE) and 2D (HMQC and HMBC) NMR and comparison with literature data of known compounds.


Assuntos
Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Iridaceae/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Rizoma/química
18.
Phytochemistry ; 64(4): 851-3, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14559280

RESUMO

Two new long chain alkyl p-coumaric acid esters (2-3) along with eicosanyl trans-p-coumarate (1) were isolated from chloroform extract of the roots of Tanacetum longifolium. The structures of new compounds were assigned as 21'-hydroxyheneicosanyl-4-hydroxy-(cis and trans) p-coumarate (2a, 2b) and 27'-hydroxy heptacosanyl-cis-p-coumarate (3) by extensive chromatographic and spectroscopic analysis and by comparison with literature data of known compounds.


Assuntos
Ácidos Cumáricos/química , Ácidos Cumáricos/isolamento & purificação , Tanacetum/química , Ésteres/química , Ésteres/isolamento & purificação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Estruturas Vegetais/química
19.
J Chromatogr A ; 976(1-2): 265-75, 2002 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-12462618

RESUMO

The investigation of aroma compounds of the essential oils of dried fruits of black pepper (Piper nigrum) and black and white "Ashanti pepper" (Piper guineense) from Cameroon by means of solid-phase microextraction (SPME) was carried out for the first time to identify the odorous target components responsible for the characteristic odor of these valuable spices and food flavoring products. By means of GC-flame ionization detection (FID) and GC-MS (using different polar columns) the main compounds (concentration >3.0%, calculated as area of GC-FID analysis using a non-polar fused-silica open tubular RSL-200 column) of the SPME headspace samples of P. nigrum (black) and P. guineense (black and white) were found to be: P. nigrum (black)--germacrene D (11.01%), limonene (10.26%), beta-pinene (10.02%), alpha-phellandrene (8.56%), beta-caryophyllene (7.29%), alpha-pinene (6.40%) and cis-beta-ocimene (3.19%); P. guineense (black)--beta-caryophyllene (57.59%), beta-elemene (5.10%), bicyclogermacrene (5.05%) and alpha-humulene (4.86%); and P. guineense (white)--beta-caryophyllene (51.75%), cis-beta-ocimene (6.61%), limonene (5.88%), beta-pinene (4.56%), linalool (3.97%) and alpha-humulene (3.29%). The most intense odor impressions of the essential oils of the various dried pepper fruits were given byprofessional perfumers as follows: P nigrum (black)--fine, pleasant black pepper note; P. guineense (black)--black pepper top-note; and P. guineense (white)--pleasant white pepper note. These analytical results for the SPME headspace samples of three different pepper species from Cameroon are in accordance with the olfactoric data of the corresponding essential oils. A GC-sniffing technique was used to correlate the single odor impression of the identified SPME headspace volatiles of the three investigated pepper samples with the following results: themain compounds such as beta-caryophyllene, germacrene D, limonene, beta-pinene, alpha-phellandrene and alpha-humulene, as well as minor constituents such as delta-carene, beta-phellandrene, isoborneol, alpha-guaiene, sarisan, elemicin, calamenene, caryophyllene alcohol, isoelemicin, T-muurolol, cubenol and bulnesol, are of greatest importance for the characteristic pepper odor notes of these three Piper samples. Further aroma impressions can be attributed to mono- and sesquiterpenes, hexane, octane and nonane derivatives.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Óleos Voláteis/análise , Piper/química
20.
J Agric Food Chem ; 50(16): 4643-6, 2002 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-12137490

RESUMO

The aroma compounds of rocket salad (Eruca sativa) SPME headspace samples of fresh leaves were analyzed using GC, GC-MS, and olfactometry. More than 50 constituents of the Eruca headspace could be identified to be essential volatiles, responsible for the characteristic intense green; herbal; nutty and almond-like; Brassicaceae-like (direction of cabbage, broccoli, and mustard); and horseradish-like aroma of these salad leaves. As aroma impact compounds, especially isothiocyanates, and derivatives of butane, hexane, octane, and nonane were identified. 4-Methylthiobutyl isothiocyanate (14.2%), cis-3-hexen-1-ol (11.0%), cis-3-hexenyl butanoate (10.8%), 5-methylthiopentyl isothiocyanate (9.3%), cis-3-hexenyl 2-methylbutanoate (5.4%), and 5-methylthiopentanenitrile (5.0%) were found in concentrations higher than 5.0% (calculated as % peak area of GC analysis using a nonpolar column).


Assuntos
Brassicaceae/química , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Folhas de Planta/química , Olfato , Alcanos/análise , Butanos/análise , Hexanos/análise , Isotiocianatos/análise , Octanos/análise
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