In vitro ovicidal and larvicidal activities of aqueous and ethanolic extracts of stem bark of Nauclea latifolia (Rubiaceae) on Heligmosomoides bakeri (Nematoda, Heligmosomatidae) Josué Wabo Poné1, Payne V. Khan1, Alidou M. Ngangout1, Claire Komtangi Marie1, Jeannette Yondo1, Gertrude Mbogning Tayo1, Mbida Mpoame1, Bilong C.F. Bilong2 1Laboratory of Biology and Applied Ecology, Department of Animal Biology, Faculty of Science, University of Dschang, PO Box 067, Dschang, Cameroon 2Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, PO Box 812, Yaoundé, Cameroon Corresponding author: Wabo Poné Josué, E-mail: waboponejosue@yahoo.fr
Abstract The use of synthetic anthelminthics is confronted with the development of resistant strains, high cost and unavailability. Available local resources which are efficient and less expensive are an alternative to the limits of these anthelminthics. This study evaluated the ovicidal and larvicidal efficacy of aqueous and ethanolic extracts of Nauclea latifolia. The eggs of the parasite were obtained from faeces of artificially infected mice, and after 3 and 4 to 5 days incubation at 25°C, L1 and L2 larvae were obtained respectively. The different stages were exposed to 5 concentrations and exposition periods were 48 and 24 hours for eggs and larvae respectively. Distilled water and 1.5% dimethylsulfoxide (DMSO) were included in the assay as negative control for aqueous and organic extract respectively. The aqueous and ethanolic extracts of N. latifolia had a negative effect on development of embryo, hatching rate and larval survival of Heligmosomodes bakeri. At the concentration 5000 μg/ml, the embryonation rate of 62.7, 21.7 and 17.4% were obtained respectively for hot, cold water and ethanolic extract. 22.4, 18 and 14.5% hatching rate were obtained with hot, cold water and ethanolic extract at 5000 μg/ml. The mortality rate of L1 for the high concentration was 77.3, 89.3 and 73.9% for hot, cold water and ethanolic extract respectively while for L2 larvae, 82.7, 77.5 and 83.3% mortality rate were obtained respectively with hot, cold water and ethanolic extract. These in vitro results suggested that extracts of N. latifolia possess ovicidal and larvicidal properties. Further experiment incorporating in vivo and toxicological studies is required. Top Keywords Nauclea latifolia, Heligmosomoides bakeri, ovicidal, larvicidal, Cameroon. Top |