Baccharis reticularia DC. and Limonene Nanoemulsions: Promising Larvicidal Agents for Aedes aegypti (Diptera: Culicidae) Control.

DC. is a plant species from the Asteraceae family that is endemic to Brazil. Despite the great importance of genus, no study has been carried out regarding either the phytochemical composition of or the evaluation of its larvicidal potential. Considering the intrinsic immiscibility of essential oils, this study shows larvicidal nanoemulsions containing the phytochemically characterized essential oil and its main constituent against . The major compound found was d-limonene (25.7%). The essential oil inhibited the acetylcholinesterase, one of the main targets of insecticides. The required hydrophile-lipophile balance of both nanoemulsions was 15.0. The mean droplet sizes were around 90.0 nm, and no major alterations were observed after 24 h of preparation for both formulations. After 48 h of treatment, the estimated LC values were 118.94 μg mL and 81.19 μg mL for essential oil and d-limonene nanoemulsions, respectively. Morphological alterations evidenced by scanning electron micrography were observed on the larvae treated with the d-limonene nanoemulsion. This paper demonstrated a simple and ecofriendly method for obtaining essential oil and d-limonene aqueous nanoemulsions by a non-heating and solvent-free method, as promising alternatives for control.