A survey of bacterial, fungal and plant metabolites against Aedes aegypti (Diptera: Culicidae), the vector of yellow and dengue fevers and Zika virus

Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. Some bacterial, fungal and plant metabolites belonging to different chemical subgroups, including Amaryllidaceae alkaloids, anthracenes, azoxymethoxytetrahydropyrans, cytochalasans, 2,5-diketopiperazines, isochromanones, naphthoquinones, organic small acids and their methyl esters, sterols and terpenes including sesquiterpenes and diterpenes, were tested for their larvicidal and adulticidal activity against Ae. aegypti. Out of 23 compounds tested, gliotoxin exhibited mosquitocidal activity in both bioassays with an LC50 value of 0.0257 ± 0.001 μg/μL against 1st instar Ae. aegypti and LD50 value of 2.79 ± 0.1197 μg/mosquito against adult female Ae. aegypti. 2-Methoxy-1,4-naphthoquinone and cytochalasin A showed LC50 values of 0.0851 ± 0.0012 μg/μL and 0.0854 ± 0.0019 μg/μL, respectively, against Ae. aegypti larvae. In adult bioassays, fusaric acid (LD50= 0.8349 ± 0.0118 μg/mosquito), 3-nitropropionic acid (LD50 = 1.6641 ± 0.0494 μg/mosquito) and α-costic acid (LD50 = 2.547 ± 0.0835 μg/mosquito) exhibited adulticidal activity. Results from the current study confirm that compounds belonging to cytochalsin, diketopiperazine, naphthoquinone and low molecular weight organic acid groups are active and may stimulate further SAR investigations.