ABSTRACT
Long chain aliphatic methyl ketone series of C7-C15 were tested for repellency activity against the malaria transmitting mosquito Anopheles gambiae s.s. All methyl ketones produced a dose dependent (P < 0.001) repellency response with 2-tridecanone giving comparable protection efficacy to DEET at 10% and 1% concentrations. Aliphatic methyl ketones of C7-C10 had lower activity than those of C11-C15. However, within this range compounds with odd carbon atoms (2-undecanone, 2-tridecanone and 2-pentadecanone) were more effective than compounds with even carbon atoms (2-decanone and 2- dodecanone). Comparable repellency activity of 2-tridecanone to DEET show that, it may save as Anopheles gambiae s.s. mosquito repellent.
Subject(s)
Anopheles/drug effects , DEET/pharmacology , Insect Repellents/pharmacology , Insect Vectors/drug effects , Ketones/pharmacology , Animals , Female , Humans , Ketones/chemistryABSTRACT
Long chain aliphatic methyl ketone series of C7-C15 were tested for repellency activity against the malaria transmitting mosquito Anopheles gambiae s.s. All methyl ketones produced a dose dependent (P0.001) repellency response with 2-tridecanone giving comparable protection efficacy to DEET at 10 and 1concentrations. Aliphatic methyl ketones of C7-C10 had lower activity than those of C11-C15. However; within this range compounds with odd carbon atoms (2-undecanone; 2-tridecanone and 2-pentadecanone) were more effective than compounds with even carbon atoms (2-decanone and 2- dodecanone). Comparable repellency activity of 2-tridecanone to DEET show that; it may save as Anopheles gambiae s.s. mosquito repellent
Subject(s)
Anopheles , Culicidae , Fatty Acids , Insect Repellents , KetonesABSTRACT
The behavioural responses of caged individual teneral Glossina morsitans morsitans on waterbuck and ox and on feeding membranes with and without smears of different doses of waterbuck sebum were compared. No significant difference was found in the initial landing behaviour on the two animals, nor on treated and control parts of the membrane. However, the subsequent behaviours of the flies were significantly different. Whereas none of the flies that landed on the ox showed any escape behaviour, more than a third of those that initially landed on waterbuck departed before probing. Similar results were obtained on feeding membranes treated in part with 1.0 or 1.4 mg cm(-2) of waterbuck sebum. Moreover, flies that landed on waterbuck or its sebum changed probing sites more often and probed significantly longer. The proportions that initiated feeding during the 10 min observation period were also significantly less. Our results suggest the presence of both volatile and non-volatile allomones on waterbuck which would account for low numbers of flies found attracted to and feeding on waterbuck in the wild.
