Bioactive profiling, larvicidal and pupicidal activities of Crateva adansonii against two developmental stages of malaria vector, Anopheles gambiae.

Abstract

Mosquito-borne diseases continue to pose significant public health challenges globally. Synthetic insecticides, raise concerns regarding their environmental impact and human health risks. This study evaluates the effectiveness of Crateva adansonii crude extracts against malaria vector Anopheles gambiae. The leaf, stem and root were extracted with ethanol, GC-MS analysis was done and a concentration of 1%, 5%, 10%, 15% and 20% was used for the bioassay. Mortality data was recoded, and the lethal concentrations were estimated. Bioactive profiling of the crude extracts revealed the presence of hexadecanoic acid, 1-(2-cyclohexyliminocyclopentyl) ethanone, heptadecanoic acid, N-(2-amino-2-oxoethyl) tetradec-2-ynamide and octadecanoic acid for leaf extract. Presence of tetradecane, hexadecane, octadecane, 5-methoxyquinoline-6-carbonitrile, 1-methoxy-3-methylsulfanylbenzene, and Octadecanoic acid was revealed for bark extracts. Additionally, presence of (E)-octadec-6-enoic acid, diethyl bis(trimethylsilyl) silicate, 1-methyl-4-phenyl-5-sulfanylidene-1,2,4-triazolidin-3-one and 3-(furan-2-yl)-4-prop-2-enyl-1 H-1,2,4-triazole-5-thione was revealed for bark extracts. Larvicidal activity recorded 100% larval mortality at 15% and 20% concentrations within 12, 18, and 24 h for the root extracts. 20% concentration of the leaf extract recorded 100% mortality in 6 h. The root extract recorded the lowest lethal concentration against the larvae at 0.04% and 8.07% for LC₅₀ and LC₉₀ respectively at 24 h. Similarly, complete mortality was observed in the leaf and bark extract at 20% concentration in 6 h with the lowest LC₅₀ and LC₉₀ being 1.78 and 14.75 respectively. Ethanolic extract of C. adansonii plant exhibited strong insecticidal activities against malaria vector. Use of plant product as plant-based mosquito control agent will help in reducing the eco-toxic effects of synthetic chemicals.