Characterization and in silico and in vivo insecticidal effects of marjoram essential oil and its nanoemulsion on Tribolium castaneum and Oryzaephilus surinamensis


ÇİÇEK S., BULAK KORKMAZ Y., TÜZÜN B., Işık S., ÖZOĞUL Y., ÖZOĞUL F.

Journal of Stored Products Research, cilt.117, 2026 (SCI-Expanded, Scopus) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 117
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1016/j.jspr.2026.103028
  • Dergi Adı: Journal of Stored Products Research
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Compendex
  • Anahtar Kelimeler: ADME/T, Insecticide activity, Marjoram essential oil, Molecular docking, Nanoemulsion
  • Sivas Cumhuriyet Üniversitesi Adresli: Evet

Özet

Marjoram essential oil (MEO) exhibits notable insecticidal activity; however, its practical application in stored-product protection is constrained by high volatility, low aqueous dispersibility, and physicochemical instability. To overcome these limitations, a nanoemulsion formulation of MEO (MEO-N) was developed using ultrasonic homogenization to enhance stability and bioefficacy. Physicochemical characterization included particle size and zeta potential analysis using dynamic light scattering (DLS) with a Zetasizer instrument and morphological evaluation by transmission electron microscopy (TEM), while chemical composition was determined by gas chromatography–mass spectrometry (GC–MS). MEO-N formed spherical nanoparticles with an average droplet size of 159 nm and a zeta potential of −19.1 mV, indicating good colloidal stability and uniform dispersion. GC–MS analysis identified carvacrol (43.07%), linalool (19.35%), γ-terpinene (7.53%), and terpinene (7.32%) as the principal constituents. Insecticidal activity was evaluated using a contact toxicity bioassay under controlled laboratory conditions against two major stored-product pests, Tribolium castaneum and Oryzaephilus surinamensis. MEO-N exhibited dose- and time-dependent insecticidal effects. In T. castaneum, 500 and 1000 ppm resulted in 43% and 56.67% mortality after 7 days, respectively. In O. surinamensis, 100% mortality was achieved within 120 h at 500 ppm and within 48 h at 1000 ppm. Molecular docking analysis revealed strong binding affinities of carvacrol and thujyl alcohol isomers to selected insect target proteins, suggesting potential molecular mechanisms underlying toxicity, while ADME/T predictions supported favorable bioactivity-related properties. Overall, the results indicate that MEO-N is a promising plant-based nanoformulation for the management of stored-product insect pests.