title: Larvicidal effect of aqueous and ethanolic extracts of Senna alata on Anopheles gambiae, Culex quinquefasciatus and Aedes aegypti.
abstract: Senna alata is locally used in South Eastern Nigeria in the treatment of several infections which include ringworm and other parasitic skin diseases.The larvicidal activities of aqueous and ethanolic leaf and stem extracts of S. alata were evaluated in static bioassays, on fourth instar larvae of Anopheles gambiae, Culex quinquefasciatus and Aedes aegypti, at extract concentrations of 0.15, 0.30, 0.45, 0.60 and 0.75% w/v, for 72 hours. Mortality of larvae exposed to the different extracts increased with increase in extract concentration and time of exposure. This study revealed a differential potency of the extracts used and a difference in susceptibility of larvae to the extracts as evident by the 72hLC₅₀ values obtained. The leaf extract proved to be more lethal to the larvae than the stem extract as judged by the 72hLC₅₀ values obtained both for the aqueous as well as the ethanolic extracts assayed. Phytochemical screening of the plant parts investigated revealed the presence of some plant metabolites, which have been reported in separate studies to be lethal to mosquito larvae. Results obtained from this study suggest that the leaf and stem extracts of S. alata possess a promising larvicidal potential which can be exploited in mosquito vector control.
authors.affiliation: Faculty of Pharmacy, University of Uyo, Nigeria. upema84@yahoo.com
authors.forename: Ubulom Peace Mayen
authors.initials: UP
authors.lastname: Edwin
authors.forename: Imandeh Godwin
authors.initials: IG
authors.lastname: Nyiutaha
authors.forename: Akpabio Eno
authors.initials: AE
authors.lastname: Essien
authors.forename: Opara Kenneth
authors.initials: OK
authors.lastname: Nnamdi
authors.forename: Ekanem Mfon
authors.initials: EM
authors.lastname: Sunday
mesh_terms: D000330:Aedes / Q000187:drug effects*; D000818:Animals; D000852:Anopheles / Q000187:drug effects*; D003465:Culex / Q000187:drug effects*; D000431:Ethanol / Q000737:chemistry; D007306:Insecticides / Q000737:chemistry / Q000494:pharmacology; D007814:Larva / Q000187:drug effects; D009032:Mosquito Control / Q000379:methods; D018515:Plant Leaves / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D012676:Senna Extract / Q000737:chemistry* / Q000494:pharmacology*; D029846:Senna Plant / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D007306:Insecticides; D014867:Water; D000431:Ethanol; D012676:Senna Extract