Acaricidal activity of Lippia adoensis var. koseret essential oil against Varroa destructor: molecular insights into the potential molecular interactions of its major constituent, linalool

Honey bees are vital pollinators, responsible for about one-third of global food crop pollination. Despite their importance, their populations are declining worldwide, largely due to Varroa destructor , an ectoparasitic mite that feeds on both adult bees and pupae. Although synthetic acaricides have been widely used, their overuse has driven mite resistance development. In Ethiopia, Lippia adoensis var. koseret has been used to control mites and ticks, though not yet specifically tested against Varroa mites. Hydrodistillation of L. adoensis var. koseret leaves yielded 0.5% (v/w) essential oil, with 21 compounds identified by GC–MS, accounting for 88.22% of the oil. Linalool was the predominant constituent (56.46%). Both the oil and linalool exhibited dose-dependent moderate acaricidal activity against adult female V. destructor mites under laboratory conditions, with 4 h-LC 50 values of 583 µg/mL (95% CI: 370–1288 µg/mL) and 244 µg/mL (95% CI: 140–439 µg/mL), respectively. Docking analysis of (R)-linalool yielded predicted docking scores of − 4.699 kcal/mol against the homology-modeled octopamine β2 receptor (Octβ2R) and − 4.773 kcal/mol against the AlphaFold-predicted structure of acetylcholinesterase (AChE) from V. destructor . The study was limited to adult female mites under laboratory conditions, and no direct assessment of honey bee or brood safety was performed. Overall, these findings provide preliminary evidence warranting further investigation of L. adoensis var. koseret essential oil and linalool, particularly regarding their efficacy, selectivity, safety, and molecular targets under semi-field and colony conditions. The moderate susceptibility of adult V. destructor to linalool also supports further evaluation of its potential for structural optimization to enhance acaricidal efficacy.