Abstract:
As malaria burden persists in most parts of the developing world, the concept of implementation of new strategies to control the disease continue to gain support. ln Kenya, mosquito population has increased to unprecedented levels as the insects are now a common sight in places they were previously not known to habit. Mosquitoes species belonging to genera Anopheles, Culex, and Aedes are the principal vectors of etiologic agents of various diseases like malaria. filariasis, Japan encephalitis (JE), dengue fever, dengue hemorrhagic fever (DHF) and yellow fever to mention just but a few. It is known that elimination of the vector is one of the most effective ways of controlling disease transmission. This takes the approach of using adulticides and larvicides. Whereas the former is well established, it has limitations like the challenges of targeting mobile adult mosquitoes and resistance of mosquitoes to insecticides. Larval control has long been an option for disease control but it has been greatly under developed and underutilized approach especially in tropical Africa where it may be of much utility than is generally appreciated. Killing mosquito larvae before they emerge as adults can reduce or eliminate the need for ground or aerial application of pCnli\.i\.i¢> l.u kill mosquitoes. During the search for new. effective and environmentally bcnignnatural larvicidal compounds. larvicidal activity of nine enriched fractions and one pure compound from mycelium of basidiomycetes serialized JO5444 were investigated. Bioactivity-guided fractionation and purification afforded one pure novel compound identified as (oxiran-2-yl)methylpentanoate by its spectral data. The LC50 and LCQQ at 24 hours of the pure compound against larvae of Ae aegypti in their late third and early fourth instars were studied and found to be l.50ppm and l.90ppm respectively. The complete structure of the purified compound was obtained from both lD and 2D NMR experiments, and analysis of the spectra obtained allowed complete 1H and BC NMR assignments. The ‘H NMR and BC NMR data for the purified compound have been provided. Fungal secondary metabolites are therefore hereby reported and proposed as a complimentary tool for control of mosquitoes and hence reduce transmission of diseases that they vector.
