Molluscicidal activity of crown of Christ (Euphorbia splendens var. hislopii) (Euphorbiaceae) latex submitted to pH variation
| Autor: | Maurício Carvalho de Vasconcellos, Fátima Eliana Ferreira Lopes, Ivonise Paz da Silva, Virgínia Torres Schall, José Augusto Albuquerque dos Santos |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2003 |
| Předmět: |
Euphorbia
Multidisciplinary biology lcsh:Biotechnology Euphorbiaceae Euphorbia splendens var. hislopii biology.organism_classification World health Biomphalaria sp Horticulture molluscicidal activity Bulinus sp lcsh:TP248.13-248.65 parasitic diseases Botany Bioassay Biomphalaria glabrata Bulinus pH variation |
| Zdroj: | Brazilian Archives of Biology and Technology, Volume: 46, Issue: 3, Pages: 415-420, Published: JUN 2003 Brazilian Archives of Biology and Technology, Vol 46, Iss 3, Pp 415-420 (2003) Brazilian Archives of Biology and Technology v.46 n.3 2003 Brazilian Archives of Biology and Technology Instituto de Tecnologia do Paraná (Tecpar) instacron:TECPAR |
| Popis: | Laboratory and field bioassays have confirmed the specificity of the molluscicidal activity of the Euphorbia splendens var. hislopii latex (crown of Christ) (Euphorbiaceae) over snails of the species Biomphalaria glabrata, B. tenagophila, B. straminea, B. pfeifferi and Bulinus sp. in the control of Schistosoma mansoni. In the present study, the effect of the pH variation on lethal concentration (LC90) over B. tenagophila was evaluated. Bioassays with the aqueous solutions of the latex ranging from 0.4 to 12 µl/l were adjusted for pH of 5.0; 6.0; 7.0 and 8.0, and tested in accordance with methods standardized by World Health Organization. The results obtained indicated that the minor concentration of the latex occurred at pH 6.0 (LC90 = 3.2 µl/l) and the maximum at pH 8.0 (LC90 = 10.3 µl/l). Lethal concentrations adjusted for pH 5.0 and 7.0 were 3.4 µl/l and 4,7µl/l, respectively. From the results it could be concluded that the molluscicidal toxicity was not altered when the concentrations were adjusted for pH 5.0 and 6.0, as we observed that mortality rate was 100% starting at a concentration of 2.0 µl/l, not the same for the concentrations with adjustment for pH 7.0 and 8.0.Bioensaios de laboratório e de campo têm comprovado a especificidade da ação moluscicida do látex da Euphorbia splendens var. hislopii (coroa-de-Cristo) (Euphorbiaceae) para os moluscos das espécies Biomphalaria glabrata, B. tenagophila, B. straminea, B. pfeifferi e Bulinus sp. No presente estudo foi investigado o efeito da variação do pH na concentração letal (CL90) testada para B. tenagophila. Bioensaios com soluções aquosas do látex variando de 0,4 a 12,0 µl/l foram ajustadas aos valores de pH 5,0; 6,0; 7,0 e 8,0, e testadas de acordo com os métodos padronizados pela Organização Mundial da Saúde. Os resultados obtidos indicam que a menor concentração letal do látex ocorreu em pH 6,0 (CL90 = 3,2 µl/l) e a maior em pH 8,0 (LC90 = 10,3 µl/l). As concentrações letais (LC90) ajustadas em pH 5,0 e 7,0 foram 3,4 µl/l e 4,7 µl/l, respectivamente. A partir destes dados conclui-se que a toxicidade do moluscicida não se alterou quando as concentrações foram ajustadas em pH 5,0 e 6,0, pois observou-se que a mortalidade foi de 100% a partir da concentração de 2,0 µl/l, o que não ocorreu nas concentrações com ajuste de pH 7,0 e 8,0. |
| Databáze: | OpenAIRE |
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