RESUMO
An extract from the pericarps of I. lancifolia afforded two dihydrochalcones (1 and 2) and two flavonolignans (3 and 4), with compounds 2-4 being of novel structure. The antioxidant activities of compounds 1-4 were evaluated through the measurement of malondialdehyde production, and Q(1/2) (concentration necessary for 50% inhibition of autoxidation) data were calculated. The Q(1/2) values obtained for 1-4 and the standard compounds alpha-tocopherol and quercetin were 6.9, 4.7, 5.5, 4.8, 12.1, and 7.6 microg/mL, respectively.
Assuntos
Antioxidantes/química , Chalcona/química , Flavonoides/química , Lignanas/química , Plantas Medicinais/química , Animais , Antioxidantes/farmacologia , Química Encefálica/efeitos dos fármacos , Brasil , Sequência de Carboidratos , Chalcona/análogos & derivados , Chalcona/farmacologia , Flavonoides/farmacologia , Lignanas/farmacologia , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Ratos , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Substâncias Reativas com Ácido Tiobarbitúrico/químicaRESUMO
The association between an in vivo oxidative stress condition of the liver and hepatic porphyria during HCB intoxication is postulated. After 30 days of treatment, HCB (25 mg/kg b.w.) promotes an induction of microsomal cytochrome P450 system, increase in microsomal superoxide anion generation accompanied by increased levels of liver lipid peroxidation, as measured by the production of thiobarbituric acid reactants and by spontaneous visible chemiluminescence. Concomitantly, liver antioxidant defenses are slightly modified, with decreased activity of glutathione peroxidase, superoxide dismutase and glucose-6-phosphate dehydrogenase contributing to an oxidative stress condition of the liver. These liver biochemical alterations are closely related to increased levels of urinary coproporphyrin, plasma AST and ALT activities and to the onset of liver morphological lesions.
Assuntos
Fungicidas Industriais/toxicidade , Hexaclorobenzeno/toxicidade , Fígado/efeitos dos fármacos , Animais , Coproporfirinas/urina , Sistema Enzimático do Citocromo P-450/metabolismo , Eritrócitos/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Fígado/metabolismo , Masculino , Estresse Oxidativo , Porfirias/induzido quimicamente , Porfirias/metabolismo , Ratos , Ratos WistarRESUMO
The hydroethanol extract of the roots of Petiveria alliacea L. (Phytolaccaceae) has been investigated previously as an antitumor agent against mouse Ehrlich ascites. The extract and its methanol, butanol and ether fractions exhibited an antimitotic effect on sea urchin egg development. The aqueous fraction did not produce inhibition of cell cleavage. At the first cleavage the inhibition, at the lowest concentration (10 micrograms/ml), produced by the ether fraction was 42%, whereas the inhibition produced by the total extract and by the other fractions was only 5 to 10% showing that the ether fraction was the most active. Even at higher concentrations the butanol and methanol fractions inhibit the cleavage about 30%. At the first cleavage, the ED50 of the hydroethanol extract and of the ether fraction were 45.02 and 12.40 micrograms/ml, respectively. Furthermore, in the second cleavage, the hydroethanol extract was about twice as potent as the methanol or butanol fractions (ED50 of 22.40, 44.80 and 54.10 micrograms/ml, respectively).
Assuntos
Mitose/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Óvulo/crescimento & desenvolvimento , Ouriços-do-MarRESUMO
The hydroethanol extract of the roots of Petiveria alliacea L. (Phytolaccaceae) has been investigated previously as an antitumor agent against mouse Ehrlich ascites. The extract and its methanol, butanol and ether fractions exhibited an antimitotic effect on sea urchin egg development. The aqueous fraction did not produce inhibition of cell cleavage. At the first cleavage the inhibition, at the lowest concentration (10 micrograms/ml), produced by the ether fraction was 42 per cent , whereas the inhibition produced by the total extract and by the other fractions was only 5 to 10 per cent showing that the ether fraction was the most active. Even at higher concentrations the butanol and methanol fractions inhibit the cleavage about 30 per cent . At the first cleavage, the ED50 of the hydroethanol extract and of the ether fraction were 45.02 and 12.40 micrograms/ml, respectively. Furthermore, in the second cleavage, the hydroethanol extract was about twice as potent as the methanol or butanol fractions (ED50 of 22.40, 44.80 and 54.10 micrograms/ml, respectively)
Assuntos
Animais , Mitose/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Divisão Celular , Óvulo/crescimento & desenvolvimento , Ouriços-do-MarRESUMO
The antibacterial and antifungic activities of two kaurenic acids, ent kaurenoic acid and cinnamoylgrandifloric acid isolated from a hexane extract of aerial parts of Mikania laevigata, were investigated and compared with the activities of other kaurenic acid derivatives substituted on carbon-15. Only acetylgrandifloric acid (ent-kaur-16-en-15 alpha-acetyloxy-19-oic) and its epimer xylopic acid (ent-kaur-16-en-15 beta-acetyloxy-19-oic) displayed significant antibacterial activity at concentrations greater than or equal to 250 micrograms/ml, the 15 alpha epimer being the most active.
Assuntos
Diterpenos/farmacologia , Fungos/efeitos dos fármacos , Bacillus cereus/efeitos dos fármacos , Brasil , Fenômenos Químicos , Química , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Plantas Medicinais , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacosRESUMO
The antibacterial and antifungic activities of two kaurenic acids, ent kaurenoic acid and cinnamoylgrandifloric acid isolated from a hexane extract of aerial parts of Mikania laevigata, were investigated and compared with the activities of other kaurenic acid-derivatives substituted on carbon-15. Only acetylgrandifloric acid (en-kaur-16-en-15 alfa-acetyloxy-19-oic) and its epimer xylopic acid (ent-kaur-16-4n-15 beta-acetyloxy-19-oic) displayed significant antibacterial activity at concentrations >=250 microng/ml., the 15 alfa epimer being the most active
Assuntos
Bactérias/efeitos dos fármacos , Diterpenos/farmacologia , Fungos/efeitos dos fármacos , Bacillus cereus/efeitos dos fármacos , Brasil , Química , Extratos Vegetais/farmacologia , Plantas Medicinais , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacosRESUMO
The antibiotic activity of 16 diterpenes and of 2 phenanthrene derivatives of diterpene origin, isolated from Brazilian plants was investigated against bacteria, yeasts, dermatophytes and aflatoxin-producing fungi. Eight of the compounds were completely inactive. None showed inhibitory activity against the Gram-negative bacteria assayed or against the Aspergillus species. The phenanthrene derivatives, chemically very similar to phytoalexins isolated from orchids, were especially active.
Assuntos
Bactérias/efeitos dos fármacos , Diterpenos/farmacologia , Fungos/efeitos dos fármacos , Fenantrenos/farmacologia , Leveduras/efeitos dos fármacos , Brasil , Fenômenos Químicos , Química , Extratos Vegetais/farmacologiaRESUMO
The antibiotic activity of 16 diterpenes and of 2 phenanthrehene derivatives of diterpene origin, isolated from Brazilian plants was investigated against bacteria, yeasts, dermatophytes and aflatoxin-producing fung. Eight of the compounds were completely inactive. None showed inhibitory activity against the Gram-negative bacteria assaywed or aginst the Aspergillus species. The phenanthrene derivatives, chemically very simular to phytoalexins isolated from orchids, were especially active
