Adulticidal and larvicidal efficacy of some medicinal plant extracts against tick, fluke and mosquitoes

The adulticidal and larvicidal effect of indigenous plant extracts were investigated against the adult cattle tick Haemaphysalis bispinosa Neumann, 1897 (Acarina: Ixodidae), sheep fluke Paramphistomum cervi Zeder, 1790 (Digenea: Paramphistomatidae), fourth instair larvae of malaria vector, Anopheles subpictus Grassi and Japanese encephalitis vector, Culex tritaeniorhynchus Giles (Diptera: Culicidae). The aim of this study was to evaluate the toxic effect of leaf hexane, chloroform, ethyl acetate, acetone and methanol extracts of Annona squamosa L, Centella asiatica (L) Urban, Gloriosa superba L., Mukia maderaspatensis (L) M.Roem, Pergularia daemia (Forsk.) Chiov. and Phyllanthus emblica L were exposed to different concentrations. All plant extracts showed moderate toxic effect on parasites after 24 h of exposure; however, the highest mortality was found in leaf hexane extract of A. squamosa, methanol extracts of G. superba and P. emblica against H. bispinosa (LC50 = 145.39, 225.57 and 256.08 ppm); methanol extracts of C asiatica, G. superba, P. daemia and P. emblica against A cervi (LC50 = 77.61, 60.16, 59.61, and 60.60 ppm); acetone, ethyl acetate extracts of A. squamosa, methanol extract of C asiatica, acetone extracts of G. superba, ethyl acetate, hexane and methanol extracts of P. daemia against A. subpictus (LC50 = 17.48, 18.60, 26.62, 18.43, 34.06, 13.63, and 50.39 ppm); and chloroform, ethyl acetate extracts of A squamosa, ethyl acetate extract of P. daemia, ethyl acetate and methanol extracts of P. emblica against C tritaeniorhynchus (LC50 = 63.81, 60.01. 31.94, 69.09, and 54.82 ppm), respectively. These results demonstrate that methanol extracts of C asiatica, G. superba, P. daemia and A emblica extracts may serve as parasites control even in their crude form. (C) 2009 Elsevier B.V. All rights reserved.