Résumé
Aromatic plant distillation produces residues rich in phenolic compounds known to be bioactive. In this context, residues from the hydrodistillation of Mentha piperita L., Cymbopogon citratus Stapf, and Eucalyptus camaldulensis Dehnh were chemically and biologically analyzed. The ethanol percentages (70%, 50%, and 30%) were evaluated by determining antioxidant activity using 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging, total phenolic content, and total flavonoid content. Antifungal activity was evaluated “in vitro” against Fusarium oxysporum, Alternaria alternata, Trametes versicolor, and Coniophora puteana using the diffusion method in malt-agar medium. Antitermite activity was also assessed against Reticulitermes flavipes using the most active extract with low ethanol concentrations (50% and 30%). The optimum ethanol concentration to extract phenolic compounds is 70% for TFC and 30% for TPC, and the antioxidant activity was 0.45 ± 0.01 mg/mL (IC50). The most active extracts were the ethanolic ones, particularly for Eucalyptus camaldulensis, presenting 100% inhibition against the mycelial growth of Coniophora puteana and Alternaria alternata at 1 mg/mL and 0.5 mg/mL, respectively. For antitermite activity, EE50 was the most effective, with a 24% termite survival rate and a degraded food supply surface of 28%. These data suggest the potential use of hydrodistillation residues for biopesticide development.