Nature-Identical Safranal and Dihydrocoumarin from Ageratina adenophora ((Spreng., 1970) King and H. Rob.) Target Energy Metabolism to Control Solenopsis invicta Buren, 1972 (Hymenoptera: Formicidae)

The bio-prospecting of bioactive phytochemicals from invasive flora presents a sustainable paradigm for the ecologically conscious management of major invasive pest <i>S. invicta</i>. <i>Ageratina adenophora</i>, while recognized for its allelopathic insecticidal properties, exhibits poorly characterized toxicological profiles and mechanistic underpinnings against <i>S. invicta</i>, warranting systematic investigation to elucidate its mode of action. This study elucidates the bioactive insecticidal compounds of <i>A. adenophora</i> and their toxicological impacts on <i>S. invicta</i>, including behavioral, metabolic, and enzymatic perturbations, via liquid chromatography-mass spectrometry (LC-MS) profiling. The ethanol extracts of the roots, stems, and leaves of <i>A. adenophora</i> have shown control effects on <i>S. invicta</i>, with an LC₅₀ (50% lethal concentration) of 331.847, 188.256, and 166.253 mg/mL at 48 h, respectively. Metabolite profiling of <i>A. adenophora</i> revealed that safranal and dihydrocoumarin are relatively high in plant leaves, and they showed significant insecticidal activity and behavioral inhibitory effects on <i>S. invicta</i> with LC₅₀ 349.042 mg/L and 118.336 mg/L at 48 h, respectively. Notably, these two bioactive compounds disrupted the normal energy production through glucose metabolism and the citrate cycle, which eventually led to the death of <i>S. invicta</i>. Further, these two compounds also activated the detoxification metabolic pathway of <i>S. invicta</i>. These findings provide a theoretical basis for the use of these bioactive compounds in the integrated management of <i>S. invicta</i> and may lead to the development of a new biopesticide.