In silico investigation and experimental validation of pistagremic acid isolated from Pistacia integerrima against Rhipicephalus microplus and Sarcoptes scabiei

<i>Rhipicephalus microplus</i> and <i>Sarcoptes scabiei</i> are major ectoparasites affecting both humans and animals, causing significant economic losses to the dairy and agricultural sectors. This study aimed to evaluate the <i>in vitro</i> and <i>in silico</i> efficacy of pistagremic acid (PA), a natural compound isolated from <i>Pistacia integerrima</i>, against these parasites. Different concentrations of the compound were tested using the adult immersion test (AIT) and larval packet test (LPT) to assess their <i>in vitro</i> effects on mites and various tick life stages. Molecular docking was conducted to examine the interactions of PA with glutathione S-transferases (GSTs) of <i>S. scabiei</i> and <i>R. microplus</i> proteins. The results demonstrated high <i>in vitro</i> acaricidal activity, with significant efficacy in both AIT and LPT assays. <i>In silico</i> studies identified PA as a key bioactive compound, showing strong binding interactions with <i>S. scabiei</i> GST (binding energy: 10.0 kcal/mol) compared to permethrin (-8.1 kcal/mol) and with <i>R. microplus</i> GST (docking score: 7.8 kcal/mol) compared to ivermectin (-8.3 kcal/mol). Overall, PA shows strong potential as a plant-derived alternative for managing tick and mite infestations, supporting its further exploration as a novel acaricidal agent.