Efficacy of Some Pyrethroid Nanoemulsions against cotton Leafworm Spodoptera littoralis (Boisd.): Toxicity, Biochemical and Molecular Docking Studies

Abd Elnabi, Amany Desoky; Badawy, Mohamed E.I.; Saad, Abdel-Fattah S. A.; Mohamed, Sondos A.

doi:10.21608/ejchem.2020.45275.2946

Efficacy of Some Pyrethroid Nanoemulsions against cotton Leafworm Spodoptera littoralis (Boisd.): Toxicity, Biochemical and Molecular Docking Studies

Document Type : Original Article

Authors

¹ Researcher at Plant Protection Research Institute, Agricultural Research Center, Egypt

² Department of Pesticide Chemistry and Technology, Faculty of Agriculture, 21545-El-Shatby, Alexandria University, Alexandria, Egypt

³ Plant Protection Department, Faculty of Agriculture (Saba Basha), Alexandria University, Alexandria, Egypt

⁴ Agriculture Research Center, Plant Protection Research Institute (PPRI). Egypt

10.21608/ejchem.2020.45275.2946

Abstract

Although pesticides are favorable for controlling the pests because more than 30– 40 % of the Although pesticides are favorable for pest controlling because more than 30– 40 % of the food production is lost due to pests, however, the extensive use of pesticides has harmful effects on the environment and health. Recently, nanotechnology techniques are used in developing agrochemical formulations, nanoemulsions as new approach have attracted great attention in delivery of many poorly soluble in water active compounds. In this study some most widely used pyrethroid insecticides (cypermethrin, deltamethrin and lambdacyhalothrin) were formulated as nanoemulsions by high energy method (ultrasonication). The droplet sizes of prepared nanoemulsions have been investigated by Dynamic Light Scattering (DLS) and Transmission Electron Microscope (TEM), characterization result reveals the size of particles in the range 24.42-84.99 nm. Formulated nanoemulsions in comparative with the active ingredient (ai) and emulsifier concentrate (EC) were evaluated against 4th instar larvae of S. littoralis, and the in vivo activity levels of targeted enzymes, acetylcholinesterase (AChE) and adenosine triphosphate (ATPase) were studied in two bioassay methods (leaf dipping and topical application). Our finding showed that cypermethrin nanoemulsion has the highest activity with LC50 = 19.92 mg/l and LD50= 2.11 ng/lavra. Furthermore, the developed nano-formulation showed good toxicity levels on AChE and ATPase compared to the active ingredient and EC formulations. The protein-ligands docking were also studied and the docking poses showed that the insecticides had a good binding affinity to the active site of the target enzymes. On this basis, these results suggest that oil in water (O/W) nanoemulsions would be very useful and can be applied for delivery insecticide formulations.

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