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1.
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
2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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
11.
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
12.
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
13.
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
14.
Antioxidants (Basel) ; 3(1): 81-98, 2014 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26784665

RESUMO

The essential oil of juniper berries (Juniperus communis L., Cupressaceae) is traditionally used for medicinal and flavoring purposes. As elucidated by gas chromatography/flame ionization detector (GC/FID) and gas chromatography/mass spectrometry (GC/MS methods), the juniper berry oil from Bulgaria is largely comprised of monoterpene hydrocarbons such as α-pinene (51.4%), myrcene (8.3%), sabinene (5.8%), limonene (5.1%) and ß-pinene (5.0%). The antioxidant capacity of the essential oil was evaluated in vitro by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging, 2,2-azino-bis-3-ethylbenzothiazoline-6 sulfonic acid (ABTS) radical cation scavenging, hydroxyl radical (ОН(•)) scavenging and chelating capacity, superoxide radical ((•)O2(-)) scavenging and xanthine oxidase inhibitory effects, hydrogen peroxide scavenging. The antioxidant activity of the oil attributable to electron transfer made juniper berry essential oil a strong antioxidant, whereas the antioxidant activity attributable to hydrogen atom transfer was lower. Lipid peroxidation inhibition by the essential oil in both stages, i.e., hydroperoxide formation and malondialdehyde formation, was less efficient than the inhibition by butylated hydroxytoluene (BHT). In vivo studies confirmed these effects of the oil which created the possibility of blocking the oxidation processes in yeast cells by increasing activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx).

15.
Biochimie ; 95(11): 2069-75, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23896375

RESUMO

Hydrogen sulfide (H2S) has been identified as the third gasotransmitter. Beside its role as signaling molecule in the cardiovascular and nervous system the antioxidant and cyto-protective properties of H2S have gained much attention. In the present study we show that cyanate, an uremic toxin which is found in abundant concentration in sera of patients suffering from chronic kidney disease (CKD), can abrogate the antioxidant and cytoprotective activity of H2S via S-carbamoylation reaction, a reaction that previously has only been shown to have a physiological effect on cysteine groups, but not on H2S. Carbamoylation strongly inhibited the free radical scavenging (ABTS(+·) and alkylperoxyl ROO(·)) properties of H2S. The extent of intracellular ROS formation induced by ROO(·) was diminished by H2S whereas carbamoylation counteracted the protective effect. Reagent HOCl was rapidly inactivated by H2S in contrast to the carbamoylated compound. Protein modification by HOCl was inhibited by H2S but carbamoylation significantly reduced the effect. Thus, S-carbamoylation of low molecular weight thiols by abrogating their antioxidant potential may contribute to the higher oxidative stress observed in CKD.


Assuntos
Cianatos/metabolismo , Sulfeto de Hidrogênio/metabolismo , Estresse Oxidativo , Insuficiência Renal Crônica/metabolismo , Antioxidantes/metabolismo , Linhagem Celular , Cianatos/química , Cisteína/análogos & derivados , Cisteína/química , Cisteína/metabolismo , Sequestradores de Radicais Livres/sangue , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/metabolismo , Humanos , Sulfeto de Hidrogênio/química , Insuficiência Renal Crônica/patologia , Transdução de Sinais
16.
Nat Prod Commun ; 7(8): 1095-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22978238

RESUMO

The essential oils of four chemotypes of Thymus vulgaris L. (Lamiaceae) were analyzed for their composition and antibacterial activity to assess their different properties. GC-MS and GC-FID analyses revealed that the essentials oils can be classified into the chemotypes thymol (41.0% thymol), geraniol (26.4% geraniol), linalool (72.5% linalool) and 4-thujanol/terpinen-4-ol (42.2% cis- and 7.3% trans-sabinene hydrate, 6.5 % terpinen-4-ol). The olfactory examination confirmed the explicit differences between these chemotypes. Furthermore, antibacterial activity was investigated against several strains of two Gram-positive (Brochothrix thermosphacta and Staphylococcus aureus) and four Gram-negative food-borne bacteria (Escherichia coli, Salmonella abony, Pseudomonas aeruginosa and P. fragi). All essential oil samples were demonstrated to be highly effective against Gram-positive strains, whereas the impact on Gram-negative microorganisms was significantly smaller, but still considerable. The results obtained indicate that, despite their different properties, the essential oils of selected T. vulgaris chemotypes are potent antimicrobials to be employed as useful additives in food products as well as for therapeutic applications.


Assuntos
Terpenos/química , Thymus (Planta)/química , Thymus (Planta)/classificação , Monoterpenos Acíclicos , Monoterpenos Bicíclicos , Monoterpenos/química , Odorantes , Timol/química
17.
Biochimie ; 94(11): 2441-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22776434

RESUMO

N-carbamoylation is the non-enzymatic reaction of cyanate with amino groups. Due to urea-formed cyanate in uremic patients beside carbamoylated proteins also free amino acid carbamoylation has been detected, a modification which has been linked to disturbed protein synthesis as NH(2)-derivatisation interferes with peptide bond formation. HOCl the product of the activated MPO/H(2)O(2)/Cl(-) system is known to react with the NH(2)-group of free amino acids to form chloramines which could exert some protective effect against protein modification and cytotoxicity induced by HOCl. As N-carbamoylation may inhibit formation of chloramines we have used N-carbamoyl-threonine as a model amino acid to study its ability to limit the reactivity of HOCl with proteins (LDL and human serum albumin) and cells (THP-1 monocytes and coronary artery endothelial cells). The data indicate that N-carbamoylation completely abolished the protein- and cell-protective effect of threonine against HOCl attack. In contrast to threonine the reaction of HOCl with carbamoyl-threonine resulted in the formation of volatile oxidant species with protein modifying and cytotoxic potential. The volatile lipophilic inorganic monochloramine (NH(2)Cl) was identified as a breakdown product of this reaction.


Assuntos
Carbamatos/metabolismo , Citotoxinas/toxicidade , Ácido Hipocloroso/toxicidade , Lipoproteínas LDL/metabolismo , Oxidantes/toxicidade , Albumina Sérica/metabolismo , Treonina/análogos & derivados , Treonina/metabolismo , Uremia/metabolismo , Aldeídos/metabolismo , Linhagem Celular , Humanos , Volatilização
18.
Biochimie ; 93(4): 772-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21277933

RESUMO

Carbamoylation is the non-enzymatic reaction of cyanate with amino-, hydroxy- or thiol groups. In vivo, amino group modification (N-carbamoylation) resulting in altered function of proteins/amino acids has been observed in patients suffering from uraemia due to urea-derived cyanate. Uraemia has been linked to impaired antioxidant defense. As thiol-compounds like cysteine, N-acetyl cysteine and GSH have oxidant scavenging properties one may speculate that thiol-group carbamoylation (S-carbamoylation) may impair their protective activity. Here we report on the effect of S-carbamoylation on the ABTS free radical and HOCl scavenging property of cysteine as well on its ability to protect LDL from atherogenic modification induced by AAPH generated peroxylradicals or HOCl. The results show that S-carbamoylation impaired the ABTS free radical and HOCl scavenging property of the thiol-compounds tested. The ability of the thiols to protect LDL from lipid oxidation and apolipoprotein modification was strongly diminished by S-carbamoylation. The data indicate that S-carbamoylation could impair the free radical and HOCl scavenging of thiol-amino acids reducing their protective property against LDL atherogenic modification by these oxidant species. As S-carbamoylation is most effective at pH 7 to 5 in vivo thiol-carbamoylation may especially occur at sites of acidic extracellular pH as in hypoxic/inflammatory macrophage rich areas like the atherosclerotic plaque where increased LDL oxidation has been found and may contribute to the higher oxidative stress in uraemia.


Assuntos
LDL-Colesterol/metabolismo , Cisteína/análogos & derivados , Cisteína/metabolismo , Radicais Livres/metabolismo , Uremia/metabolismo , Antioxidantes/metabolismo , Benzotiazóis/metabolismo , LDL-Colesterol/química , Cianatos/farmacologia , Cisteína/química , Glutationa/metabolismo , Humanos , Peroxidação de Lipídeos , Lipoproteínas LDL/metabolismo , Estresse Oxidativo/fisiologia , Compostos de Sulfidrila/metabolismo , Ácidos Sulfônicos/metabolismo
19.
Nat Prod Commun ; 5(9): 1349-54, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20922989

RESUMO

The chemical compositions of selected essential oils from North Africa, especially Morocco, of geranium, wild Moroccan chamomile and rosemary as well as absolutes of rose and geranium were determined using GC/FID and GC/MS. These oils and absolutes were tested concerning their antimicrobial activity against some food spoilage strains obtained from fresh milk and minced meat products, like sausages and pork fillet, in accordance with ISO testing procedures. Gram-positive (Bacillus cereus and Staphylococcus aureus) and Gram-negative (Escherichia coli, Salmonella abony and Pseudomonas aeruginosa) strains were used, as well as the yeast Candida albicans. Using a serial broth dilution method, all samples demonstrated weak antimicrobial activity against the Gram-negative bacteria and the yeast, compared with the activity towards the Gram-positive bacteria.


Assuntos
Anti-Infecciosos/farmacologia , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Camomila/química , Cromatografia Gasosa-Espectrometria de Massas , Geranium/química , Testes de Sensibilidade Microbiana , Marrocos , Rosmarinus/química , Olfato
20.
Nat Prod Commun ; 5(9): 1355-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20922990

RESUMO

Cumin oil samples (Cuminum cyminum L.) from four different geographical origins were analyzed using GC-MS and GC-FID for their qualitative and quantitative composition. The major compounds in all cumin oils were the monoterpenes beta-pinene, p-cymene and gamma-terpinene and the terpenoid aldehydes cuminic aldehyde and the isomeric menthadien carboxaldehydes. All essential oils, and cuminic aldehyde, were tested, using agar diffusion and serial dilution methods, against different Gram-positive and Gram-negative bacteria isolated from different sources of food (pork fillet, minced meat and sausages) and clinical isolates, as well as three different Candida albicans isolates. All cumin oils and cuminic aldehyde exhibited a considerable inhibitory effect against all the organisms tested, except Pseudomonas spp.


Assuntos
Anti-Infecciosos/farmacologia , Cuminum/química , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Cromatografia Gasosa , Testes de Sensibilidade Microbiana
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