Phytochemical profiling in vitro and in silico evaluation of antioxidant, antimicrobial, and insecticidal properties of Moroccan matricaria chamomilla essential oil

Abstract

Chamomile (Matricaria chamomilla L.), a widely recognized medicinal plant, was investigated for its chemical composition, functional properties, and molecular characterization, focusing on samples cultivated in the Taounate region of Morocco. Essential oil (EO) was extracted using a Clevenger apparatus, and GC/MS analysis identified 26 compounds, with germacrene (19.46%), α-curcumene (19.00%), and caprinic acid (15.81%) as the major components. The EO exhibited significant antioxidant activity, with an IC50 of 456.57 µg/mL against the DPPH radical. It demonstrated strong antibacterial effects, particularly against E. coli, with an inhibition zone of 21.50 ± 0.50 mm and a minimum inhibitory concentration (MIC) of 20.00 µg/mL. Antifungal activity was also notable, inhibiting Aspergillus niger by 31.19 ± 0.00 mm. In fumigation tests, the EO caused 100% insect mortality at 16 µL/L after 72 h, with an LC50 of 1.86 µL/L of air, and showed a 55% repellency rate at 12 µL/cm². DNA sequencing confirmed a 99.22% similarity with Matricaria chamomilla var. recutita (L.). Furthermore, molecular docking analysis revealed strong binding affinities between the major compounds of EO-MC and key microbial and antioxidant target proteins, supporting the observed biological activities. These results highlight the EO’s antioxidant, antimicrobial, and insecticidal properties, with molecular docking analyses providing further mechanistic support. These biological activities suggest potential applications as natural food preservatives, antimicrobial agents, and plant-derived biopesticides.