Identification of Bioactive Compounds against Aedes aegypti (Diptera: Culicidae) by Bioassays and in Silico Assays

Abstract

Most of the hematophagous insects act as disease vectors, including Aedes aegypti, responsible for transmitting some of the most critical arboviruses globally, such as Dengue. The use of repellents based on natural products is a promising alternative for personal protection compared to industrial chemical repellents. In this study, the repellent effect of essential oils extracted from Lippia thymoides, Lippia alba, Cymbopogon winterianus, and Eucalyptus globulus leaves was evaluated. Essential oils used showed repellent activity against Ae. aegypti in laboratory bioassays, obtaining protection rates above 70 % from 3.75 mg/mL and higher concentration for all analyzed oils. GC/MS identified 57 constituents, which were used in the ligand‐based pharmacophore model to expose compounds with requirements for repellents that modulate mosquitoes behavior through odorant‐binding protein 1 Ae. aegypti. Ligand‐based pharmacophore model approach results suggested that repellent activity from C. winterianus, L. alba, and L. thymoides essential oils’ metabolites is related to Citronelal (QFIT=26.77), Citronelol (QFIT=11.29), Citronelol acetate (QFIT=52.22) and Geranil acetate (QFIT=10.28) with synergistic or individual activity. E. globulus essential oil's repellent activity is associated with Ledol (0.94 %; QFIT=41.95). Molecular docking was applied to understand the binding mode and affinity of the essential oils’ data set at the protein binding site. According to molecular docking, Citronelol (ChemPLP=60.98) and geranyl acetate (ChemPLP=60.55) were the best‐classified compounds compared to the others and they can be explored to develop new repellents.

Biocidal activity of Ziziphora hispanica L and Satureja calamintha Scheele L essential oils against the Callosobruchus maculatus (Fabricius) pest on cowpea seeds during storage

“…Consequently, these biochemical substances impact negatively on female fecundity and fertility, as well as on adult emergence (Saeidi and Mirfakhraie, 2017;Romani et al, 2019;Boukraa et al, 2022). The repellent effect resides in various behavioral responses of the insects transmitted by sensory hairs in their antennae that detect the chemically volatile organic compounds in the EOs (Romani et al, 2019;De Brito et al, 2021;Boukraa et al, 2022).…”

Biological effects of Lippia alba essential oil against Anopheles gambiae and Aedes aegypti

“…As the tests were carried out in hermetically closed cylinders, the 2.5 and 5% concentrations could have started to intoxicate the mosquitoes or impaired their sensory systems. Cutaneous application of the citral chemotype of L. alba EO protects against mosquito bites 41 . The EO of L. alba , composed mainly of 2, 7 octadione-1-butoxy and 2-isopropenyl-5-methyl hex-4-enol, has a repellent activity, unlike that composed mainly of carvone and limonene 39 , 40 .…”

“…aegypti , in addition to acetylcholinesterase 72 , 73 . One of the potential mechanisms of action of the repellent compounds in EOs such as Lippia thymoides , Cymbopogon winterianus , Eucalyptus globulus and L. alba is their interaction with OBP 1 41 .…”

“…aegypti, in addition to acetylcholinesterase 72,73 . One of the potential mechanisms of action of the repellent compounds in EOs such as Lippia thymoides, Cymbopogon winterianus, Eucalyptus globulus and L. alba is their interaction with OBP 1 41 . The irritant effect observed in the contact repellency test may not only be as a consequence of the intrinsic irritancy of the EO, since a spatial repellency effect was observed for the two mosquito species.…”

Biological effects of Lippia alba essential oil against Anopheles gambiae and Aedes aegypti

“…quinquefasciatus [39,40]. L. alba EO could be used as skin repellents [40,41,42], although the one evaluated by Castillo et al [39] did not repel Ae. aegypti females.…”