EFFECT OF PIPERACEAE EXTRACT IN SCHISTOSOMIASIS VECTOR

RAPADO LN (1), KATO MJ (2), KAWANO T (1).

(1) Lab Parasitology and Malacology, Institute Butantan, São Paulo, Brazil; (2) Lab. Chemistry, University São Paulo, São Paulo, Brazil.

Schistosomiasis occurs in 54 countries mainly in the South America, the Caribbean, Africa and east of the Mediterranean. In Brazil, 5-6 million people are infected and 30 thousand are exposed to infection risk. One of the methods more efficient to control this disease is molluscicides application that eliminates or reduces the intermediate host population. Concerning to with the environmental preservation, the high cost and recurrent resistance of snail to the synthetic molluscicide has been stimulated the study of molluscicides with plant origin. The extracts from the Piperaceae family has a diversified and bioactive chemistry compounds such as essential oils, unsaturated amides, pyrones, flavonoids, monoterpenes, sesquiterpenes, arylpropanoids and lignoids. It was studied the molluscicide action of the Piperaceae on adult snails of Biomphalaria glabrata. Studies with 13 plant species had been carried through, totalizing 15 extracts from stem, leaf and root. Screening was performed to choose a better molluscicide and snails were submitted to the concentrations of 100ppm and 500ppm from each extract. In eleven extracts the mortality rate with 100ppm was obtained 100%, then they were studied at the lower concentrations to get less lethal concentration. The leaf extracts of following plants had presented acute toxic effect with 100% of mortality in snail at the Piper crassinervium (60ppm), Piper hostmannianum (40ppm), Piper diospyrifolium (30ppm), Piper cuyabanum (20ppm) and Piper aduncum (10ppm). Due to the good molluscicidal action these extracts had been fractioned and submitted to blastula, gastrula, trochophore and veliger stage of B. glabrata for the study of the ovicida effect.

KEY WORDS: Biomphalaria glabrata, Schistosomiasis, Piperaceae, molluscicide.

CORRESPONDENCE TO: Ludmila Nakamura Rapado, Laboratory Parasitology and Malacology, Institute Butantan, Av. Vital Brazil, 1500 CEP 05503-900 São Paulo, São Paulo, Brazil. Phone: + 90 37267222 (2158/2281). Email: ludmila@butantan.gov.br