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1.
An. acad. bras. ciênc ; 90(1): 449-459, Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886902

RESUMO

ABSTRACT This study evaluated the chemical composition and antioxidant activity of fatty acids from the marine red algae Pterocladiella capillacea (S. G. Gmelin) Santelices & Hommersand 1997 and Osmundaria obtusiloba (C. Agardh) R. E. Norris 1991. The gas chromatography mass spectrometry (GC-MS) identified nine fatty acids in the two species. The major fatty acids of P. capillacea and O. obtusiloba were palmitic acid, oleic acid, arachidonic acid and eicosapentaenoic acid. The DPPH radical scavenging capacity of fatty acids was moderate ranging from 25.90% to 29.97%. Fatty acids from P. capillacea (31.18%) had a moderate ferrous ions chelating activity (FIC), while in O. obtusiloba (17.17%), was weak. The ferric reducing antioxidant power (FRAP) of fatty acids from P. capillacea and O. obtusiloba was low. As for β-carotene bleaching (BCB), P. capillacea and O. obtusiloba showed a good activity. This is the first report of the antioxidant activities of fatty acids from the marine red algae P. capillacea and O. obtusiloba.


Assuntos
Rodófitas/química , Ácidos Graxos/análise , Ácidos Graxos/química , Antioxidantes/análise , Antioxidantes/química , Valores de Referência , Análise de Variância , Sequestradores de Radicais Livres/análise , beta Caroteno/análise , FMN Redutase/análise , Cromatografia Gasosa-Espectrometria de Massas
2.
An Acad Bras Cienc ; 90(1): 449-459, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29424393

RESUMO

This study evaluated the chemical composition and antioxidant activity of fatty acids from the marine red algae Pterocladiella capillacea (S. G. Gmelin) Santelices & Hommersand 1997 and Osmundaria obtusiloba (C. Agardh) R. E. Norris 1991. The gas chromatography mass spectrometry (GC-MS) identified nine fatty acids in the two species. The major fatty acids of P. capillacea and O. obtusiloba were palmitic acid, oleic acid, arachidonic acid and eicosapentaenoic acid. The DPPH radical scavenging capacity of fatty acids was moderate ranging from 25.90% to 29.97%. Fatty acids from P. capillacea (31.18%) had a moderate ferrous ions chelating activity (FIC), while in O. obtusiloba (17.17%), was weak. The ferric reducing antioxidant power (FRAP) of fatty acids from P. capillacea and O. obtusiloba was low. As for ß-carotene bleaching (BCB), P. capillacea and O. obtusiloba showed a good activity. This is the first report of the antioxidant activities of fatty acids from the marine red algae P. capillacea and O. obtusiloba.


Assuntos
Antioxidantes/análise , Antioxidantes/química , Ácidos Graxos/análise , Ácidos Graxos/química , Rodófitas/química , Análise de Variância , FMN Redutase/análise , Sequestradores de Radicais Livres/análise , Cromatografia Gasosa-Espectrometria de Massas , Valores de Referência , Fatores de Tempo , beta Caroteno/análise
3.
An Acad Bras Cienc ; 87(2): 1113-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25860969

RESUMO

Marine invertebrates are capable of synthesizing bioactive compounds, which may be beneficial to human health. The aim of this study was to evaluate the antioxidant, hemolytic, antimicrobial and cytotoxic activities of crude extract (70% EtOH), and dichloromethane (DCM), ethyl acetate (EtOAc), and aqueous (Aq) fractions of the marine zoanthid Palythoa caribaeorum. The phenolic compound contents of the crude extract, DCM, EtOAc and Aq fractions were 12.33, 18.17, 10.53, and 3.18 mg GAE per gram, respectively. DPPH radical scavenging activity showed slight variation. IC50 of crude extract, DCM, EtOAc and Aq fractions were 11.13, 11.25, 11.74, and 11.28 µg mL(-1), respectively. Among the sample, ferrous ion chelating was the highest in crude extract (IC50 302.90 µg mL(-1)), followed by EtOAc, Aq, and DCM fractions with 457.77, 547.91, and 641.82 µg mL(-1), respectively. Ferric-reducing antioxidant power showed optical density at about 0.5. The samples tested exhibited low hemolytic activity under 10% up to a concentration of 50 µg mL(-1). No antimicrobial activity was observed against any of the tested bacterial strains. For the cytotoxic activity, LC50 of DCM, crude extract, EtOAc, and Aq were 52.10, 83.06, 86.34, and 117.45 µg mL(-1), showing high toxicity.


Assuntos
Antozoários/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Artemia/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Animais , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bioensaio , Relação Dose-Resposta a Droga , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana
4.
Int J Biol Macromol ; 72: 1136-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25192853

RESUMO

Resveratrol can also inhibit the activation of proinflammatory mediators and cytokines at the early gene expression stage. It is well known that lectins are sugar-binding proteins that act as both pro- and anti-inflammatory molecules. Thus, the objective of this work was to verify the binding of a polyphenol compound with a lectin of Canavalia maritima (ConM) based on their ability to inhibit pro-inflammatory processes. To accomplish this, ConM was purified and crystallized, and resveratrol was soaked at 5mM for 2h of incubation. The crystal belongs to the monoclinic space group C2, the final refinement resulted in an Rfactor of 16.0% and an Rfree of 25.5%. Resveratrol binds in the rigid ß-sheet through H-bonds and hydrophobic interaction with amino acids that compose the fifth and sixth ß-strands of the rigid ß-sheet of ConM. The ConM and resveratrol inhibited DPPH oxidation, showing synergic activity with the most effective ratio of 2:3 and carbohydrate binding site is not directly related to antioxidant activity. It is the interaction between ConM and resveratrol that indicates the synergism of these two molecules in acting as free radicals scavengers and in reducing the inflammatory process through the inhibition of many pro-inflammatory events.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Polifenóis/química , Polifenóis/metabolismo , Estilbenos/química , Estilbenos/metabolismo , Sítios de Ligação , Compostos de Bifenilo/química , Canavalia , Cristalografia por Raios X , Sequestradores de Radicais Livres/farmacologia , Glicosilação/efeitos dos fármacos , Ligação de Hidrogênio/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Simulação de Acoplamento Molecular , Picratos/química , Ligação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína , Quercetina/farmacologia , Resveratrol
5.
An Acad Bras Cienc ; 86(1): 251-63, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24676166

RESUMO

Natural antioxidants found in marine macroalgae are bioactive compounds known to play an important role in the prevention of diseases associated with aging cells protecting them against the oxidative damage. The purpose of this study was to evaluate the antioxidant and cytotoxic activity of ethanolic extracts of two species of red seaweeds, Amansia multifida and Meristiella echinocarpa. In vitro antioxidant activity was determined by DPPH radical scavenging assay, ferric-reducing antioxidant power (FRAP) assay, ferrous ion chelating (FIC) assay, ß-carotene bleaching (BCB) assay and total phenolic content (TPC) quantification. Cytotoxicity was evaluated with the brine shrimp Artemia sp. lethality test. The TPC values observed in the present study indicated that both species A. multifida and M. echinocarpa are rich in phenolic compounds, reaching values of 45.40 and 28.46 mg gallic acid equivalent (GAE) g-1 of ethanolic extract, respectively. DPPH radical scavenging and ferrous ion chelating showed values of 60% and 17%, respectively. Both seaweed extracts inhibited ß-carotene oxidation by approximately 40%. None of the algal extracts were potentially cytotoxic. The results have showed that extracts of both species of marine red algae exhibit antioxidant potential and low toxicity. They are sources of natural antioxidant compounds.


Assuntos
Antioxidantes/farmacologia , Alga Marinha/química , Animais , Antioxidantes/toxicidade , Artemia/efeitos dos fármacos , Bioensaio , Brasil , Oxirredução
6.
Pharm Biol ; 49(2): 167-74, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20942613

RESUMO

CONTEXT: Lobophora variegata J.V. Lamouroux (Dictyotaceae) is a brown marine alga widely encountered in the Brazilian sea coast that presents high content of fucans. Anti-inflammatory effects of fucans are reported mostly in models in vitro, but little is known about its effects in vivo. OBJECTIVE: To investigate vascular and cellular effects of a sulfated polysaccharide from the brown marine algae L. variegata (SP-Lv) in acute inflammatory models. MATERIALS AND METHODS: SP-Lv was isolated by DEAE-cellulose and analyzed by agarose gel electrophoresis and evaluated for its inhibitory effect on paw edema, vascular permeability, leukocyte migration and peritoneal nitrite content induced by zymosan in Wistar rats. Anticoagulant activities and possible systemic toxicity were also evaluated. RESULTS: SP-Lv inhibited the paw edema (120 min: 1.42 ± 0.11 vs. 0.95 ± 0.05 mL), plasma exudation (21.53 ± 0.62 vs. 11.96 ± 0.68 µg/g), nitrite content (4.42 ± 0.33 vs. 2.86 ± 0.003 µM) and leukocyte migration (5.15 ± 1.21 vs. 1.99 ± 0.16 cells/10(3) mL) induced by zymosan. SP-Lv and L-NAME reduced the paw edema (60-120 min) elicited by L-arginine. However, at 180 min SP-Lv effect was more accentuated and sustained until 240 min, while that of L-NAME was abolished. Similarly to indomethacin, SP-Lv inhibited the entire edema time-course induced by phospholipase A(2), except for the time of 60 min. DISCUSSION AND CONCLUSION: The anti-edematogenic effect of SP-Lv seems to occur via inhibition of nitric oxide synthase and cyclooxygenase activities. These results suggest a potential applicability of polysaccharides from alga origin in acute inflammatory conditions.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Phaeophyceae/química , Polissacarídeos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/toxicidade , Anticoagulantes/isolamento & purificação , Anticoagulantes/farmacologia , Anticoagulantes/toxicidade , Brasil , Modelos Animais de Doenças , Edema/tratamento farmacológico , Edema/fisiopatologia , Eletroforese em Gel de Ágar , Indometacina/farmacologia , Inflamação/fisiopatologia , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Polissacarídeos/isolamento & purificação , Polissacarídeos/toxicidade , Prostaglandina-Endoperóxido Sintases/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo
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