Chemical Characterization of Volatile Terpenoids in Teucrium polium L. Essential Oil Evaluated by GC-MS/FID and Its Associated Biological Properties.

The study aimed to characterize the chemical composition, and evaluate the antioxidant, antibacterial, and insecticidal activities of Teucrium polium essential oil (TP-EO) collected from the northeast of Morocco. The antioxidant activity was carried out using ABTS and DPPH radical scavenging assays, whereas the insecticidal properties of TP-EO were evaluated against Sitophilus granarius and Tribolium confusum. In addition, the antibacterial effects of TP-EO were tested against a broad spectrum of Gram-positive and Gram-negative bacterial strains. GC-MS/FID analyses allowed to identify a total of 64 volatile compounds in TP-EO. The major constituents were β-eudesmol (10.91%), β-pinene (10.63%), α-eudesmol acetate (9.22%), and α-pinene (7.69%). Furthermore, TP-EO exhibited remarkable bactericidal effects against all tested bacteria except Klebsiella pneumoniae 1 and Proteus penner, with the MIC values ranging from 2.5 ± 0.1 to 20 ± 0.1 µL/mL. In addition, TP-EO displayed notable insecticidal effects against both Sitophilus granarius and Tribolium confusum, and moderate antioxidant activity. Therefore, TP-EO could serve as a valuable, natural alternative in food safety, organic farming, and pest management, providing a sustainable option to reduce reliance on synthetic chemicals.