Biocontrol of Mosquitoes using Biocoil Produced from Cola millenii Extracts

Abstract

Malaria is one of the major causes of mortality and morbidity among various population in the tropics. Mosqiutoes are the vectors of this important disease. Presently, due to the resistance of insects to synthetic chemicals, there are ongoing efforts by researchers to develop biological substances for controlling the vectors in a bid to eradicate the disease. This research investigated C. millenii for its insecticidal potential against Anopheles mosquito. The leaf extracts of C. millenii were obtained using ethanol and n-Hexane. The extracts were screened for bioactive substances using standard analytical protocols. Biocoil was developed from the extract and the insecticidal efficacy was evaluated in the laboratory against larvae and adults of Anopheles stephensi. The qualitative results revealed that the plant contained alkaloids, saponins, tannins, glycosides, flavonoids and terpenoids in varying amounts. Furthermore, the leaf extract had a significant (P < 0.05) lethal effect on mosquito larva at very low concentration recording a median lethal concentration (LC₅₀) of 1.71 ppm in ethanol extract, while the pulp extract had LC₅₀ of 792.34 ppm. The biocoil produced from the leaf extracts of the plant gave highly promising results in the control of the adult mosquito. These suggest that Cola millenii leaf contain bioactive substances that may be exploited in the control of mosquito.