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1.
Nat Prod Commun ; 9(4): 481-2, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24868861

RESUMO

A raw extract and four extractive fractions were obtained from Cedrus brevifolia (Cyprus cedar) bark. They were all studied regarding the phenolic content and profile using spectrophotometry and HPLC-DAD-ESI-MS. The antioxidant activity was investigated using in vitro assays: DPPH and ABTS radicals scavenging and reducing power assays. The ethyl acetate fraction had the highest total phenolic and proanthocyanidin contents; a taxifolin-O-hexoside, catechin, epicatechin and procyanidin oligomers (three dimers, two trimers) were identified in this fraction. The ethyl acetate fraction was found to possess the highest DPPH and ABTS radicals scavenging effects (EC50 = 13.9 +/- 0.3 and 2.3 +/- 0.0 microg/mL, respectively) and reducing capacity (EC50 = 9.1 +/- 0.1 microg/mL). Antioxidant effects were highly correlated with total phenolic and proanthocyanidin contents (r = 0.89-0.99). These results suggest that Cedrus brevifolia bark is a new source of antioxidants.


Assuntos
Antioxidantes/química , Cedrus/química , Fenóis/química , Casca de Planta/química , Benzotiazóis/química , Compostos de Bifenilo/química , Cromatografia Líquida de Alta Pressão/métodos , Sequestradores de Radicais Livres , Picratos/química , Extratos Vegetais/química , Proantocianidinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Ácidos Sulfônicos/química
2.
Rev Med Chir Soc Med Nat Iasi ; 117(2): 545-50, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24340544

RESUMO

UNLABELLED: The wood of mature Abies alba Mill. (silver fir) trees is used in construction and furniture industries, the bark being the main waste product. AIM: This study aimed to investigate possible therapeutic applications of Abies alba bark waste. MATERIAL AND METHODS: A raw extract and four extractive fractions were obtained from silver fir bark. They were also studied regarding their polyphenolic content (Folin-Ciocalteu assay). The ethyl acetate extractive fraction was further studied regarding its ability to scavenge free radicals (DPPH, superoxide anion and hydroxyl radicals) and to chelate ferrous ions. RESULTS AND DISCUSSION: The ethyl acetate fraction contained the highest amount of polyphenols (47.72 +/- 0.38 g gallic acid equivalents/100 g). Its DPPH scavenging and ferrous ions chelating abilities (EC50 = 7.9 +/- 0.1 and 1.56 +/- 0.05 microg/ml) were comparable to those of the positive controls, catechin (EC50 = 7.10 +/- 0.05 microg/ml) and EDTA-Na2 (EC50 = 1.27 +/- 0.01 microg/ml), respectively. It also scavenged superoxide anion and hydroxyl radicals with EC50 values of 53.30 +/- 5.91 and 63.12 +/- 1.78 microg/ml, respectively. CONCLUSIONS: The ability of the ethyl acetate fraction to scavenge free radicals and chelate ferrous ions justifies further studies on the possible therapeutic applications of its antioxidant potential.


Assuntos
Abies , Antioxidantes/farmacologia , Sequestradores de Radicais Livres/farmacologia , Quelantes de Ferro/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Antioxidantes/química , Sequestradores de Radicais Livres/química , Quelantes de Ferro/química , Fitoterapia/métodos , Extratos Vegetais/química , Polifenóis/análise
3.
Rev Med Chir Soc Med Nat Iasi ; 117(2): 551-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24340545

RESUMO

UNLABELLED: In the Eastern Mediterranean region the wood of Pinus brutia Ten. is used as building material, the bark being the main waste of the wood production processes. A study was designed to explore possible medicinal applications for the bark waste. This paper reports on the superoxide dismutase-like and NO scavenging effects of bark extracts. MATERIAL AND METHODS: Bark extracts (a raw hydromethanolic extract and its fractions) were initially screened regarding their ability to scavenge DPPH radical. The superoxide dismutase-like and NO scavenging effects were further evaluated. Catechin and quercetin were the positive controls in all antioxidant assays. RESULTS AND DISCUSSION: According to the EC50 values, all extracts (11.8 +/- 0.1 - 21.10 +/- 0.05 microg/ml) efficiently scavenged DPPH radical in comparison to quercetin (3.13 +/- 0.05 microg/ml) and catechin (6.36 +/- 0.05 microg/ml). The raw extract, diethyl ether and ethyl acetate fractions (449.46 +/- 1.75, 115.43 +/- 0.25 and 278.3 +/- 2.3 microg/ml, respectively) exhibited higher superoxide dismutase-like effects in comparison to catechin (> 645.1 microg/ml). In NO scavenging assay, the raw extract, ethyl acetate and aqueous fractions (160.63 +/- 0.85, 162.96 +/- 0.52 and 160.23 +/- 2.35 microg/ml, respectively) showed a scavenging ability similar to that of quercetin (156.76 +/- 5.05 microg/ml) and higher than the one developed by catechin (242.66 +/- 7.65 microg/ml). CONCLUSIONS: As superoxide anion and NO are important mediators in inflammation, our results support a possible use of Pinus brutia bark waste to develop nutraceuticals with efficiency in disorders involving oxidative and inflammatory stress.


Assuntos
Sequestradores de Radicais Livres/farmacologia , Óxido Nítrico/farmacologia , Fitoterapia , Pinus , Extratos Vegetais/farmacologia , Superóxido Dismutase/farmacologia , Suplementos Nutricionais , Óxido Nítrico/química , Extratos Vegetais/química , Superóxido Dismutase/química
4.
J Med Food ; 16(11): 984-91, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24195749

RESUMO

A crude hydromethanolic extract from Pinus brutia bark and its fractions (diethyl ether, ethyl acetate, n-butanol, and aqueous fractions) were studied with regard to their phenolic content and antioxidant activities. The total phenolics and proanthocyanidins in each extract were quantified by spectrophotometric methods; the polyphenolic profile was analyzed by RP-HPLC-DAD-ESI-MS. All extracts were tested with regard to their ability to scavenge free radicals (ABTS radical cation, superoxide and hydroxyl radicals), reduce ferric ions, and inhibit 15-lipoxygenase. P. brutia bark extracts had high phenolic contents (303.79±7.34-448.90±1.39 mg/g). Except diethyl ether extract, all other extracts contained proanthocyanidins ranging from 225.79±3.94 to 250.40±1.44 mg/g. Several polyphenols were identified by RP-HPLC-DAD-ESI-MS: taxifolin in diethyl ether extract, a taxifolin-O-hexoside, catechin, procyanidin dimers, and trimers in ethyl acetate extract. Except diethyl ether extract, all other extracts were effective scavengers of superoxide and hydroxyl radicals (EC50=33.5±1.1-54.93±2.85 µg/mL and 0.47±0.06-0.6±0.0 mg/mL, respectively). All extracts had noticeable 15-lipoxygenase inhibitory effects (EC50=22.47±0.75-34.43±2.25 µg/mL). We conclude that P. brutia bark is very promising for the dietary supplements industry due to its high free radical scavenging and 15-lipoxygenase inhibitory effects.


Assuntos
Antioxidantes/farmacologia , Araquidonato 15-Lipoxigenase/metabolismo , Inibidores Enzimáticos/farmacologia , Radicais Livres/metabolismo , Pinus/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Antioxidantes/análise , Inibidores Enzimáticos/análise , Casca de Planta/química , Polifenóis/análise
5.
Rev Med Chir Soc Med Nat Iasi ; 117(1): 250-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24505924

RESUMO

UNLABELLED: Cedrus brevifolia (Hook. f.) Henry, a species endemic to Cyprus, has not been studied regarding its constituents and potential biological activities. MATERIAL AND METHODS: A crude extract from Cedrus brevifolia bark and its four fractions (diethyl ether, ethyl acetate, n-butanol and aqueous fractions) were investigated regarding their capacity to inhibit 15-lipoxygenase and scavenge reactive oxygen species (superoxide anion and hydroxyl radicals). Catechin was used as positive control in all antioxidant assays. RESULTS AND DISCUSSION: In the superoxide anion radical scavenging assay, the crude extract showed the highest activity (EC50 = 57.73 +/- 1.25 microg/mL) comparable to that of the positive control, catechin (EC50 = 52.60 +/- 1.65 microg/mL). All other fractions exhibited noticeable scavenging effects against superoxide radical, their EC50 values ranging from 76.33 +/- 3.50 to 91.06 +/- 4.45 microg/mL. The ethyl acetate and n-butanol fractions were the most active in the hydroxyl radical scavenging (EC50 = 580.20 +/- 18.72 and 792.10 +/- 15.36 microg/mL, respectively) and 15-lipoxygenase inhibition assays (EC50 = 34.0 +/- 0.9 and 40.96 +/- 0.45 microg/mL, respectively). CONCLUSIONS: Cedrus brevifolia bark is a valuable source of compounds with reactive oxygen species and 15-lipoxygenase inhibitory activities. These results support further studies for the identification and isolation of the bioactive constituents.


Assuntos
Cedrus , Sequestradores de Radicais Livres/farmacologia , Inibidores de Lipoxigenase/farmacologia , Extratos Vegetais/farmacologia , Casca de Planta
6.
Rev Med Chir Soc Med Nat Iasi ; 116(4): 1223-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23700916

RESUMO

Nowadays cancer is still a major public health issue. Despite all the progresses made in cancer prevention, diagnosis and treatment, mortality by cancer is on the second place after the one caused by cardiovascular diseases. The high mortality and the increasing incidence of certain cancers (lung, prostate, colorectal) justify a growing interest for the identification of new pharmacological agents efficient in cancer prevention and treatment. In the last fifty years many plant-derived agents (vinblastine, vincristine, vindesine, paclitaxel, docetaxel, topotecan, irinotecan, elliptinium) played a major role in cancer treatment. Other very promising plant-derived anticancer agents (combrestatins, betulinic acid, roscovitine, purvalanols, indirubins) are in clinical or preclinical trials. Curcumin, a liposoluble polyphenolic pigment isolated from the rhizomes of Curcuma longa L. (Zingiberaceae), is another potential candidate for new anticancer drug development. Curcumin has been reported to influence many cell-signaling pathways involved in tumor initiation and proliferation. Curcumin inhibits COX-2 activity, cyclin D1 and MMPs overexpresion, NF-kB, STAT and TNF-alpha signaling pathways and regulates the expression of p53 tumor suppressing gene. Curcumin is well-tolerated but has a reduced systemic bioavailability. Polycurcumins (PCurc 8) and curcumin encapsulated in biodegradable polymeric nanoparticles (NanoCurc) showed higher bioavailability than curcumin together with a significant tumor growth inhibition in both in vitro and in vivo studies. BILITY.


Assuntos
Antineoplásicos/uso terapêutico , Curcumina/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Antineoplásicos/farmacologia , Curcumina/farmacologia , Medicina Baseada em Evidências , Humanos , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
7.
Pneumologia ; 51(1): 21-5, 2002.
Artigo em Romano | MEDLINE | ID: mdl-12043272

RESUMO

This modest study is trying to surprise the clinic shades spectrum of the pulmonary tuberculosis met at adults in the Romanati Plain zone, which was high consumption at the end of the second millennium without avoiding the new tones which AIDS and the MDR-TB brought. This things determined people to speak about the "NEW TUBERCULOSIS" of the third millennium. It had started from a number of 393 patients suffering from pulmonary tuberculosis and age over twenty. This people were in hospital between 1997-2000 at the Pneumophysiology section in the Caracal's Municipal hospital. They were grouped after this parameters: the disease type, sex, environment, occupation, beginning form, clinic form, bacteriologic exam BK, diagnosis delay, lesion stretch and associated diseases, looking to discover the profile which is the most frequently used which satisfies in high percentage many of the studied parameters. We underline that the HIV test was negative to all the new cases and readmitted positive at T3 and to all the sick people who were registered with therapeutic failure in 1997 and 1999, so the AIDS impact with tuberculosis in this zone was null. Also systematic in the last two years we made ABG at relapses, failures and chronic; the bacillus resistance was not put in evidence, thing also hard to accept. The profile the most frequently met no matter the environments life, disease type, sex, age is the fibro-cases-cavitary farm (50%) followed by the infiltrative one (35%) with an "classic" onset in more than two third of the cases, bilaterally of the injures and the diagnosis delay with at least two months at 60% from all cases and a positively of the sputum in microscopy of about 50%. At least one third of the sick people are unemployed. This profile has of course epidemic consequences an therapeutic especially.


Assuntos
Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Adulto , Antituberculosos/uso terapêutico , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Romênia/epidemiologia , Índice de Gravidade de Doença , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar/tratamento farmacológico
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