Novel tools into phytochemical profile, bioinsecticidal properties, and molecular docking analysis of Tunisian Diplotaxis erucoides (L.) DC. subsp. erucoides

Abstract

This study evaluated the insecticidal effects of Tunisian Diplotaxis erucoides (DXe) against Tribolium confusum . Active substances present in the extracts were identified through UHPLC-Q-Orbitrap-MS/MS. Repellency and mortality were assessed using different concentrations of the methanolic extract at various time points. The results revealed that D. erucoides is rich in bioactive phytochemicals, including delphinidin, eriodictyol, fisetin, gluconapine, isorhamnetin, petinidin 3-O-glucoside, quercetin, and sakuranetin. The findings showed a clear dose-dependent relationship for the repellency effects of the Diplotaxis extract. Specifically, larvae and adult beetles displayed repellency index (RI) values of 0.85 and 0.43, respectively, when treated with a low dose of DXe. At 0.318 µL/cm², the extract demonstrated a similar level of attractancy across both developmental stages of the beetle, with RI values >1. Further analysis revealed that the median lethal time (LT50) was approximately 1.5 days. Notably, the extract exhibited a significant toxic effect, with LT50 values for larvae and adults of 1.58 and 1.83 days, respectively, at concentrations of 0.238 and 0.389 µL/cm².. Remarkably, D. erucoides was observed to kill 85.00 ± 0.22% of larvae and 65.0 ± 0.1% of adult beetles within a 48-hour exposure period. Determination of the lethal dose (LD50) established a value of 0.13 µL/cm² for larvae and 0.29 µL/cm² for adults, indicating statistically ( P < 0.05) higher lethality in larvae compared to adults. In addition, in silico docking studies were conducted against the ' Tribolium castaneum Arylalkylamine N-acyltransferase' (PDB: 6V3T ), yielding significant findings. This report revealed the bioinsecticidal potential of the D. erucoides species.