In vitro ovicidal and larvicidal activities of aqueous and ethanolic extracts of the leaves of Bidens pilosa (Asteraceae) on Heligmosomoides bakeri (Nematoda: Heligmosomatidae) Gertrude Mbogning Tayo1, Payne V.K.1, Poné J. Wabo1, Claire Komtangi Marie1, Jeannette Yondo1, Alidou M. Ngangout1, Mbida Mpoame1, Bilong C.F. Bilong2 1Laboratory of Biology and Applied Ecology, Department of Animal Biology, Faculty of Science, University of Dschang, PO Box067 Dschang, Cameroon 2Laboratory of General Biology, Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, PO Box 812, Yaoundé, Cameroon Corresponding author: J. Wabo Poné e-mail: waboponejosue@yahoo.fr
Online published on 12 November, 2012. Abstract The development of parasitic resistance vis-a-vis conventional anthelmintics, and the relatively high cost of available anthelmintics have limited the efficiency of gastro-intestinal helminth control and thus, created an interest in studying medicinal plants as an alternative means of parasitic control. The aim of this study was to assess the ovicidal and larvicidal activities of aqueous and ethanolic extracts of leaves of Bidens pilosa on eggs (fresh and embryonated), first and second larval stages of Heligmosomoides bakeri. In order to achieve this objective, the extracts were diluted in distilled water to obtain five different concentrations: 625, 1250, 2500, 3750 and 5000 μg/ml. Fresh eggs obtained from artificially infected mice feaces, embryonnated eggs and larvae (L1 and L2) were exposed to these different concentrations for 48 hours, 6 and 24 hours respectively. Distilled water and 1.5% DMSO were used as negative controls in the bioassay. In fact, distilled water and 1.5% DMSO had no effect on embryonnation, hatching and larvae survival. Contrarily, extracts of B. pilosa showed concentration dependent activities. At 5000 μg/ml, ethanolic extract inhibited 82.2% embryonic development of fresh eggs and induced 66.4% mortality of L2 larvae. In a similar study, the infused extract inhibited hatching by 95.6% of embryonnated eggs and induced the mortality of 68.9% L1 larvae. These results showed the ovicidal and larvicidal properties of B. pilosa and indicate that, this medicinal plant can be a focus for the research of new source of anthelmintics. Top Keywords Bidens pilosa, Heligmosomoides bakeri, ovicidal, larvicidal, Dschang Cameroun. Top |