title: Insecticidal activities of bark, leaf and seed extracts of Zanthoxylum heitzii against the African malaria vector Anopheles gambiae.
abstract: The olon tree, Zanthoxylum heitzii (syn. Fagara heitzii) is commonly found in the central-west African forests. In the Republic of Congo (Congo-Brazzaville) its bark is anecdotally reported to provide human protection against fleas. Here we assess the insecticidal activities of Z. heitzii stem bark, seed and leaf extracts against Anopheles gambiae s.s, the main malaria vector in Africa. Extracts were obtained by Accelerated Solvent Extraction (ASE) using solvents of different polarity and by classical Soxhlet extraction using hexane as solvent. The insecticidal effects of the crude extracts were evaluated using topical applications of insecticides on mosquitoes of a susceptible reference strain (Kisumu [Kis]), a strain homozygous for the L1014F kdr mutation (kdrKis), and a strain homozygous for the G119S Ace1R allele (AcerKis). The insecticidal activities were measured using LD50 and LD95 and active extracts were characterized by NMR spectroscopy and HPLC chromatography. Results show that the ASE hexane stem bark extract was the most effective compound against An. gambiae (LD50 = 102 ng/mg female), but was not as effective as common synthetic insecticides. Overall, there was no significant difference between the responses of the three mosquito strains to Z. heitzii extracts, indicating no cross resistance with conventional pesticides.
authors.affiliation: Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, P.O. Box 5003, Ås 1432, Norway. hans.overgaard@nmbu.no.
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Overgaard
authors.affiliation: Department of Entomology, Faculty of Agriculture, Kasetsart University, 50 Ngam Wong Wan Rd, Ladyaow, Chatuchak, Bangkok 10900, Thailand. golf.patcharawan@gmail.com.
authors.forename: Patcharawan
authors.initials: P
authors.lastname: Sirisopa
authors.affiliation: National Polytechnic High School, Marien Ngouabi University, BP 69, Brazzaville, Congo. mikolobertin@yahoo.fr.
authors.forename: Bertin
authors.initials: B
authors.lastname: Mikolo
authors.affiliation: School of Pharmacy, Department of Pharmaceutical Chemistry, Section Pharmacognosy, University of Oslo, P.O. Box 1068 Blindern, Oslo 0316, Norway. k.e.malterud@farmasi.uio.no.
authors.forename: Karl E
authors.initials: KE
authors.lastname: Malterud
authors.affiliation: School of Pharmacy, Department of Pharmaceutical Chemistry, Section Pharmacognosy, University of Oslo, P.O. Box 1068 Blindern, Oslo 0316, Norway. helle.wangensteen@farmasi.uio.no.
authors.forename: Helle
authors.initials: H
authors.lastname: Wangensteen
authors.affiliation: School of Pharmacy, Department of Pharmaceutical Chemistry, Section Pharmacognosy, University of Oslo, P.O. Box 1068 Blindern, Oslo 0316, Norway. yuanfengzou860315@163.com.
authors.forename: Yuan-Feng
authors.initials: YF
authors.lastname: Zou
authors.affiliation: School of Pharmacy, Department of Pharmaceutical Chemistry, Section Pharmacognosy, University of Oslo, P.O. Box 1068 Blindern, Oslo 0316, Norway. b.s.paulsen@farmasi.uio.no.
authors.forename: Berit S
authors.initials: BS
authors.lastname: Paulsen
authors.affiliation: National Polytechnic High School, Marien Ngouabi University, BP 69, Brazzaville, Congo. danielmassamba@yahoo.fr.
authors.forename: Daniel
authors.initials: D
authors.lastname: Massamba
authors.affiliation: Department of Entomology, Faculty of Agriculture, Kasetsart University, 50 Ngam Wong Wan Rd, Ladyaow, Chatuchak, Bangkok 10900, Thailand. stephane.duchon@ird.fr.
authors.forename: Stephane
authors.initials: S
authors.lastname: Duchon
authors.affiliation: Department of Entomology, Faculty of Agriculture, Kasetsart University, 50 Ngam Wong Wan Rd, Ladyaow, Chatuchak, Bangkok 10900, Thailand. vincent.corbel@ird.fr.
authors.forename: Vincent
authors.initials: V
authors.lastname: Corbel
authors.affiliation: Institut de Recherche pour le Développement (IRD), Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (IRD 224-CNRS 5290 UM1-UM2), Montpellier Cedex 5 34394, France. Fabrice.Chandre@ird.fr.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Chandre
mesh_terms: D000818:Animals; D000852:Anopheles / Q000187:drug effects*; D005260:Female; D007303:Insect Vectors / Q000187:drug effects*; D007306:Insecticides / Q000302:isolation & purification / Q000494:pharmacology*; D007928:Lethal Dose 50; D009032:Mosquito Control; D024301:Plant Bark / Q000737:chemistry*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D012639:Seeds / Q000737:chemistry; D032106:Zanthoxylum / Q000737:chemistry
chemical_list: D007306:Insecticides; D010936:Plant Extracts