RESUMO
Schistosomiasis is a disease of global extent reaching populations in social vulnerability. One of the control measures of this parasitosis is the use of molluscicidal substances that can fight snails of the genus Biomphalaria, intermediate hosts of Schistosoma mansoni. The aim of this work was to study the toxic activity of three mangrove species (Avicennia schaueriana Stapf. & Leech, ex Moldenke, 1939, Laguncularia racemosa (L.) CF Gaertn, 1807 and Rhizophora mangle L. 1753) on the biological activities of snails Biomphalaria glabrata. Hydroalcoholic extracts were prepared from the stem and leaves of each of the three plant species to which mollusks were exposed. The phytochemical analysis of plants showed the presence of important metabolites in the leaves and stems of L. racemosa and R. mangle, such as tannins and saponins, but the absence of these metabolites in A. schaueriana. Leaf and stem extracts of the three plant species showed low molluscicidal activity, not reaching the standards determined by the World Health Organization (WHO, 1983). L. racemosa and R. mangle has interfered with motility, feeding and oviposition of snails, unlike the extracts of A. schaueriana, which had no effect on these activities.
Assuntos
Avicennia/química , Biomphalaria/efeitos dos fármacos , Combretaceae/química , Moluscocidas/farmacologia , Extratos Vegetais/farmacologia , Rhizophoraceae/química , Animais , Moluscocidas/isolamento & purificaçãoRESUMO
The action of extracts from the stem, leaves, and fruit of Jatropha gossypiifolia on Biomphalaria glabrata was studied by analyzing survival, feeding capacity and oviposition ability. The extracts were obtained by macerating the plant parts in 92% ethanol, which were then evaporated until a dry residue was obtained and phytochemically studied. The molluscicidal activity on B. glabrata was investigated using the procedures recommended by WHO (1965). The amount of food ingested and oviposition were measured during each experiment. The extract of leaves from J. gossypiifolia was shown to be a strong molluscicidal agent, causing 100% mortality of B. glabrata, even in the lowest concentration tested, of 25 ppm. Regarding the fruit extract, there was variation in the mortality, depending on the concentration used (100, 75, 50 and 25 ppm). The snails that were in contact with the fruit extract had significant reduction in feeding and number of embryos in comparison to the control. The stem extract did not present molluscicidal activity nor had any influence on the feeding and oviposition abilities of B. glabrata, in the concentrations tested. In conclusion, the extracts of leaves and fruits of J. gossypiifolia investigated in this work show molluscicidal effect and may be sources of useful compounds for the schistosomiasis control.
Estudou-se a ação dos extratos do caule, folhas e frutos de Jatropha gossypiifolia (Pinhão-roxo) sobre Biomphalaria glabrata analisando a sobrevivência, capacidade alimentar e de oviposição. Os extratos foram obtidos pela maceração das partes do vegetal em álcool etílico 92%, evaporados até obter-se um resíduo seco e estudados fitoquimicamente. A atividade moluscicida em B. glabrata seguiu os procedimentos recomendados pela WHO (1965). A medida de quantidade de alimento ingerido e a oviposição foi realizada durante cada experimento. O extrato das folhas de J. gossypiifolia mostrou-se um forte agente moluscicida, promovendo 100% de mortalidade de B. glabrata mesmo na menor concentração testada, 25 ppm. Com o extrato dos frutos houve variação na mortalidade, de acordo com a concentração utilizada (100, 75, 50 e 25 ppm). Os caramujos em contato com o extrato dos frutos apresentaram quando comparado ao controle uma diminuição significativa nos comportamentos alimentares e de número de embriões. O extrato do caule não apresentou atividade moluscicida e nenhuma influência sobre a capacidade alimentar e de oviposição de B. glabrata nas concentrações testadas. Em conclusão, os extratos de folhas e frutos de J. gossypiifolia investigados neste trabalho apresentam efeito moluscicida e possivelmente podem ser fontes de compostos no controle da esquistossomose.
Assuntos
Animais , Feminino , Biomphalaria/efeitos dos fármacos , Jatropha/química , Moluscocidas/farmacologia , Extratos Vegetais/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Oviposição/efeitos dos fármacos , SobrevidaRESUMO
The action of extracts from the stem, leaves, and fruit of Jatropha gossypiifolia on Biomphalaria glabrata was studied by analyzing survival, feeding capacity and oviposition ability. The extracts were obtained by macerating the plant parts in 92% ethanol, which were then evaporated until a dry residue was obtained and phytochemically studied. The molluscicidal activity on B. glabrata was investigated using the procedures recommended by WHO (1965). The amount of food ingested and oviposition were measured during each experiment. The extract of leaves from J. gossypiifolia was shown to be a strong molluscicidal agent, causing 100% mortality of B. glabrata, even in the lowest concentration tested, of 25 ppm. Regarding the fruit extract, there was variation in the mortality, depending on the concentration used (100, 75, 50 and 25 ppm). The snails that were in contact with the fruit extract had significant reduction in feeding and number of embryos in comparison to the control. The stem extract did not present molluscicidal activity nor had any influence on the feeding and oviposition abilities of B. glabrata, in the concentrations tested. In conclusion, the extracts of leaves and fruits of J. gossypiifolia investigated in this work show molluscicidal effect and may be sources of useful compounds for the schistosomiasis control.