Title: | Novel use of stir bar sorptive extraction (SBSE) as a tool for isolation of oviposition site attractants for gravid Culex quinquefasciatus |
Author(s): | Carson C; Birkett MA; Logan JG; Mawa K; Pates HV; Pickett JA; Rwegoshora RT; Tungu PK; Cameron MM; |
Address: | "Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK. c.carson@warwick.ac.uk" |
DOI: | 10.1017/S0007485309006701 |
ISSN/ISBN: | 1475-2670 (Electronic) 0007-4853 (Linking) |
Abstract: | "Mosquitoes such as Culex quinquefasciatus Say (Diptera: Culicidae) are important vectors of organisms that cause disease in humans. Research into the development of effective standardized odour baits for blood-fed females (oviposition attractants), to enable entomological monitoring of vector populations, is hampered by complex protocols for extraction of physiologically active volatile chemicals from natural breeding site water samples, which have produced inconsistent results. Air entrainment and solvent extraction are technically demanding methods and are impractical for use in resource poor environments where mosquito-borne disease is most prevalent. This study reports the first use of a simple, robust extraction technique, stir bar sorptive extraction (SBSE), to extract behaviourally active small lipophilic molecules (SLMs) present in water samples collected from Cx. quinquefasciatus breeding sites in Tanzania. Extracts from a pit latrine and from a cess pool breeding site attracted more gravid Cx. quinquefasciatus in pair choice bioassays than control extracts, and coupled gas chromatography-electroantennography (GC-EAG) allowed tentative identification of 15 electrophysiologically active chemicals, including the known oviposition attractant, skatole (3-methylindole). Here, we have demonstrated, using simple pair choice bioassays in controlled laboratory conditions, that SBSE is effective for the extraction of behaviourally and electrophysiologically active semiochemicals from mosquito breeding site waters. Further research is required to confirm that SBSE is an appropriate technique for use in field surveys in the search for oviposition cues for Cx. quinquefasciatus" |
Keywords: | "Animals Behavior, Animal/drug effects Biological Assay/methods Chemistry Techniques, Analytical/*methods Chromatography, Gas Culex/*chemistry Female Fresh Water/*chemistry Gas Chromatography-Mass Spectrometry Oviposition/drug effects/*physiology Pheromone;" |
Notes: | "MedlineCarson, C Birkett, M A Logan, J G Mawa, K Pates, H V Pickett, J A Rwegoshora, R T Tungu, P K Cameron, M M eng Biotechnology and Biological Sciences Research Council/United Kingdom Research Support, Non-U.S. Gov't England 2009/03/24 Bull Entomol Res. 2010 Feb; 100(1):1-7. doi: 10.1017/S0007485309006701. Epub 2009 Mar 23" |