A Multiplatform Chemometric Approach to Modeling of Mosquito Repellents

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Figure 9.1: Some synthetic (1) and natural (2 - 4) compounds with repellent activity:

(1) DEET, (2) 2-hydroxy-6-methylbenzaldehyde, (3) catechol, (4) monoacetin; The com-

pounds 2 - 4 have been studied in the paper by Gaddaguti et al. (2016).

mosquito repellents were identified by Thireou et al. (2018). The authors used ligand-

based screening and odorant-binding protein-structure-based molecular docking. A set of

16 compounds was tested for their affinity to AgamOBP1 in vitro and repellence against

A. gambiae. Kröber et al. (2018) used an odorant-binding protein-based identification of

natural spatial repellents against A. gambiae. This study gave an insight into approach for

the identification of the biologically active molecules of natural origin that can be used

as mosquito repellents. In a research of Gaddaguti et al. (2016) repelling potential of the

Ocimum compounds (Figure 9.1) was tested against 3Q8I and 3N7H of A. gambiae.

If at least two compounds with best docking score are applied together, there is en-

hanced protection involved. So Ocimum compounds can be used further for eco-friendly

and safe repellents production. Molecular docking and molecular dynamics simulations

were utilized in a research by Mourão et al. (2021). They identified molecular scaffolds

from Caatinga Brazilian biome as potential inhibitors of the sterol carrier protein-2 from

Ae. aegypti. The biflavonoid loniflavone from leaves of Brazilian plant called catingueira

was the most promising regarding the interaction with target protein.

The attention should also be paid to the unexpected and adverse effects of different

repellents and pesticides on the human health. Roy et al. (2017) and Legeay et al. (2018)

published overviews of the unexpected and adverse effects of different repellents (DEET,

diethyl phthalate, permethrin, picaridin, DEPA, pyrethroid, tetramethrin and IR3535). Re-

cent chapter published by Khater et al. (2019) gathered a variety of commercial repellents

and gave an overview regarding safety concerns. The climate variability, primarily temper-

ature and rainfall, is an important geographic factor since climate changes have resulted

in the VBC increase (Rocklöv and Dubrow 2020; Fouque and Reeder 2019; Dhimal et al.

2015; Parham et al. 2015). Some studies indicate that temperature in Europe has increased

for 0.8C over the last 100 years (Githeko et al., 2000). Overall, the most important pre-

vention and control measures regarding VBD is vector control: reduction of the mosquito

populations and elimination of the breeding sites since “No mosquito – no VBD”.