ABSTRACT
Vatairea macrocarpa (Benth.) Ducke, Fabaceae, is popularly known as 'angelim'. Its heartwood macerate is used to treat inflammation, gastric ulcer, diabetes and infections. The oral acute and subchronic toxicity of the methanol extract of V. macrocarpa heartwood (MEVm) was evaluated. In the Hippocratic screening, a single administration of MEVm was given orally to mice at doses ranging from 100 to 5000 mg/kg. In the subchronic study, MEVm was given orally as a daily administration for thirty days to Wistar rats at doses of 20, 100 and 500 mg/kg. In Hippocrtaic screening, doses of MEVm up to 5000 mg/kg did not cause any relevant behavioral changes or deaths thus making it impossible to establish the LD50. In subchronic assay, body weight gains and food intake were significantly reduced at the last week of treatment with 20 and 500 mg/kg dose. Serum triacylglycerides, total proteins and γ-glutamyltransferase activity were significantly reduced, while alkaline phosphatase activity was elevated. In hematological parameters, MEVm increased the percentage of segmented neutrophils cells at the highest dose. All alterations observed were minor in nature and were not accompanied by any relevant clinical signs or any histopathological changes. In conclusion, the results demonstrate relative safety profile of MEVm in the experimental animals.
ABSTRACT
Stem-bark extracts, fractions and the isolated constituent, ellagic acid of Lafoensia pacari St. Hil. (Lythraceae) were in vitro assayed for antifungal activity against a panel of yeasts, hialohyphomycetes as well as dermatophytes with the microbroth dilution method. The EtOH extract and its fractions and ellagic acid exhibited activity against Candida spp and Saccharomyces cerevisiae with MIC values between 250-1000 µg/mL, but they showed no action against filamentous fungi and dermatophytes (MIC>1000 µg/mL). Active extracts were evaluated in Neurospora crassa hyphal growth inhibition and sorbitol assays and then the effect of ergosterol on the MIC of ellagic acid was studied. The active extracts and its fractions and ellagic acid showed a blotchy zone around the paper disk and induced malformations of the hypha. Besides, MIC of the ellagic acid against the Saccharomyces cerevisiae was raised from 62 to 250 µg/mL in the presence of sorbitol 0.8 M, suggesting that the ellagic acid would probably exert its action on fungal cell wall. These results indicate that ellagic acid might be the main active antifungal compound of Lafoensia pacari and further suggest that the mode of antifungal action of these extracts and ellagic acid could be associated with the inhibition of fungal cell wall.
Os extratos, frações e ácido elágico, isolados da entrecasca de Lafoensia pacari A. St.-Hil., Lythraceae, foram testados in vitro para atividade antifúngica, frente a um painel de leveduras, hialo-hifomicetos e dermatófitos, utilizando o método de microdiluição. O extrato EtOH, frações e ácido elágico exibiram atividade contra Candida spp. e Saccharomyces cerevisiae com valores de CIM entre 250-1000 µg/mL, porιm não mostraram ação contra fungos filamentosos e dermatófitos (CIM>1000 µg/mL). Os extratos ativos foram avaliados nos ensaios de inibição do crescimento das hifas de Neurospora crassa, no teste do sorbitol, e pelo estudo do efeito do ergosterol na CIM do ácido elágico. Os extratos ativos, frações e ácido elágico mostraram zonas manchadas ao redor dos discos de papel e induziram malformações nas hifas. Além disso, a CIM do ácido elágico contra Saccharomyces cerevisiae passou de 62 para 250 µg/mL na presença do sorbitol 0,8 M, sugerindo que o ácido elágico provavelmente poderia exercer ação na parede celular fúngica. Esses resultados indicam que o ácido elágico pode ser o principal composto antifúngico de Lafoensia pacari, sugerindo que o modo de ação antifúngico desses extratos e ácido elágico poderia estar associado à inibição da parede celular fúngica.