IN VITRO AND IN SILICO EVALUATIONS OF PARINARI EXCELSA AND CUSSONIA ARBOREA OILY EXTRACTS AS POTENTIAL BIOACARICIDES.

Cussonia arborea and Parinari excelsa hold significant value in traditional African medicine for treating parasitic infections. This study evaluated the acaricidal effects of oily extracts from Cussonia arborea and Parinari excelsa on two known cattle ticks (Amblyomma hebraeum and Rhipicephalus microplus) collected from infested cattle. Additionally, the impact of these oils on Triosephosphate isomerase (TIM) proteins of Rhipicephalus microplus retrieved from the RCSB Protein Data Bank (https://rcsb.org) was investigated through a molecular docking approach. Ten ticks were treated with 20 µL of oily extracts in Petri dishes for each concentration. The effects were observed for 24 h using n-hexane (20 µL) as the control. The sdf formats of the ligands were downloaded from https://pubchem.ncbi.nlm.nih.gov/, docked using the PyRx software, and visualized using the Biodiscovery studio. The ligands were harvested from the GC-MS analysis of our previous studies. The results demonstrated that the oil extracted from C. arborea achieved 100% mortality against Amblyomma hebraeum at concentrations of 2%, 5%, 10%, and 20% within 24 hours. Also, the extract achieved 100% mortality at 2% and 10% concentrations against Rhipicephalus microplus. In the in silico study, compounds 2 and 6 from C. arborea, with binding affinities of -7.9 and -7.8 kcal/mol, respectively, demonstrated stronger binding affinity against the ticks than the positive control (-7.5 kcal/mol). Compound 3 (-7.5 kcal/mol) from P. excelsa exhibited a binding affinity similar to the positive control (-7.5 kcal/mol) against the ticks. These findings suggest that the phytoconstituents from both plants hold promise as bioacaricides. [ABSTRACT FROM AUTHOR]