Larvicidal activity of methanol and chloroform extract of swertia celiata against three mosquito vectors
06 Jun 2018-The Journal of communicable diseases (Indian Society for Malaria and Communicable Diseases)-Vol. 50, Iss: 2, pp 17-24
TL;DR: The study clearly revealed that S. ciliata extract or bioactive compounds can be used as an alternative to synthetic insecticides.
Abstract: Background: Mosquitoes are an important public health concern as they spread life-threatening diseases such as malaria, filaria, Japanese encephalitis, dengue fever, chikungunya, and yellow fever. In the last decades, synthetic insecticides were extensively used for the control of these vector-borne diseases but it also reported the detrimental side-effects in human beings and pet animals. To overcome the side effects, plants-derived secondary metabolites were screened and tested for insecticidal properties. The present study deals with the insecticidal activity of chloroform and methanol extracts of Swertia celiata leaves against Culex quenquifasciatus, Aedes aegypti, and Anopheles stephensi larvae. Method: The S. celiata leaves were subjected to chloroform and methanol with 1:3 (Weight/ Volume) ratio and the extracted solvent was dried using rotary vacuum evaporator. The larvicidal activity of the extract was tested using WHO method and LC50 and LC90 were evaluated by probit analysis. Results: The LC50 value of chloroform extract of S. celiata was found to be 65.288, 67.406 and 71.608 ppm whereas LC90 was 184.721, 186.582 and 192.497 ppm against C. quinquefasciatus, Ae. aegypti and A. stephensi, respectively. The methanolic extract was also found potent; LC50 was 91.503, 101.574 and 99.104 ppm whereas LC90 was 230.823, 271.927 and 234.257 ppm against C. quinquefasciatus, Ae. aegypti and A. stephensi, respectively. Both chloroform and methanol extract were found significantly lethal to the tested mosquito vectors. Conclusion: Taken results together, chloroform extract showed higher toxicity as compared to methanolic extract against all the tested species. The study clearly revealed that S. ciliata extract or bioactive compounds can be used as an alternative to synthetic insecticides.
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