Document Type : Original Research Article


1 Islamic Azad university Khoy, West Azerbaijan Province, Iran

2 Assistant professor at Islamic Azad University, Khoy Branch, Khoy, Iran


The use of plants, especially medicinal plants, for treating diseases and controlling pests biologically has increased significantly in recent years. Wild Mountain Thyme is one of these plants widely used in Iran, especially Khoy, Iran. Concerning the importance of this plant in the traditional medicine of the region and the need for controlling grain pests, we decided to study the plant’s chemical compounds, the antibacterial effects of its essential oil, and its repelling and lethality effect. Wild Mountain Thyme was collected from the southeast of Khoy in the spring and identified in the Institute of Forests and Pastures. The plant’s essential oil was extracted by distillation with water using a Clevenger machine. The resulting oil had a yellow color and a pungent smell, and its percentage was 1.64% compared to the dry weight of the plant. A total of 37 chemical compound was identified and isolated using a gas-mass chromatography device, the main of which was carvacrol (36.8%), thymol (36.8%), gamma-terpinene (10.6%), and paracymene (8.5%). The microbial test of the essential oil of the Thymus Fedtschenkoi plant was performed on three Gram-positive bacteria (E. faecalis, S. aureus, and B. anthracis) and three Gram-negative bacteria (P. aeruginosa, Sa. paratyphi, and E. coli). Thymus Fedtschenkoi plant essential oil was effective on all Gram- and Gram-negative bacteria except for Pseudomonas aeruginosa. In addition, plant essential oil’s repellent and lethal effect on rice weevil were evaluated in three repetitions with different concentrations. The highest removal rate was at the highest concentration of 25 µl and 72 hours. The lethal effect of the plant on the weevil was at a maximum concentration of 20 µl and duration of 72 hours. LC50 and LC90 of essential plant oil were calculated and determined based on probit analysis software. Based on the results, the plant essential oil can have a good effect in controlling the rice weevil pest both in the field and warehouse0.

Graphical Abstract

Evaluation of Chemical Compound of Thyme Essential Oil and Repelling and Lethality Effect of Thyme Plant Essential Oil on Rice Weevil


Main Subjects

  1. Suggestions

    1. The desired essential oil should be extracted and compared with the plant collected from different regions for one year.
    2. The environmental effect on the amount and type of secondary metabolisms should be investigated.
    3. The effect of different stresses on the plant’s essential oil should be assessed.
    4. The type of other compounds present in this plant extract cannot be determined by extracting essential oils.
    5. Negotiating with pharmaceutical companies to prepare antibacterial solutions is necessary because the essential plant influences all warm (+) bacteria and many warm (-) bacteria.


    1. Hak, N. Zagh. The effect of flowers and plants on the human state of mind. The 8th Conference of New Researches in Science and Technology., (2015) 1-12.
    2. H. Sharifi. Secrets of medicinal plants. Hafez Navin Publications. 2003.
    3. Chi. Medical vocabulary and medicinal plants of Iran. Tehran University Publications. 1991.
    4. Chi. Iranian Medical Vocabulary and Medicinal Plants, University of Tehran Publications. 137
    5. A. Bakht, A. Hosseini, F. Mouloud, The necessity of standardizing medicinal plant extracts in research and how to do it. Razi Journal of Medical Sciences., (2015) 10-23.
    6. Mehboodi, Extraction, isolation, and identification of wheat flower plant and investigation of their cytotoxic effects. Master’s thesis, Yasouj University., (2013).
    7. Rudy, Studying the essential plant components and investigating the essential oil’s antimicrobial properties. Master thesis of Payam Noor University. (2009).
    8. Bakht, Classification of medicinal plants, Taimurzadeh Publishing Cultural Institute, Tabib Publication. (1999).
    9. M. Beygi, Approaches to producing and processing of medicinal plants, Tehran publishing house. (1995) 2.
    10. T. Khani, K. Tat, P. Han. A review of various extraction methods in plant extracts. The 4th International Conference on Recent Innovations in Chemistry and Chemical Engineering. 2017.
    11. Zargari, Medicinal Plants. Tehran University Publications. (2019).
    12. Robiston. Plant chemistry, translated by Hamad Izaddoost, Tehran University Press. 1985.
    13. Naqvi. Fighting warehouse pests using plant essences and natural toxins. New technologies in the food industry., (2016)7.
    14. Gholami, A. Nasser. Investigating the antifungal properties and identifying the chemical compounds of the essential oil of the mountain thyme plant (Thymus kotscuyanus Boiss. & Hohen.). Iranian Journal of plant physiology and biochemistry., 1 (2016) 52-62.
    15. Delazar, M. Bahmani, H.H. Shoar, A. Tabatabaei-Raisi, S. Asnaashari, L. Nahar, et al. Effect of altitude, temperature, and soil on essential oil production in Thymus fedtschenkoi flowers in Osko and surrounding areas in Iran. Journal of Essential Oil Bearing Plants., 14 (2011) 23-9.
    16. Oryzae, Effects of six plant extracts on rice weevil Sitophilus oryzae L. in the stored wheat grains. Journal of Agricultural and Biological Science., 1 (2006).
    17. I. Kim, J.Y. Roh, D.H. Kim, H.S. Lee, Y.J. Ahn. Insecticidal activities of aromatic plant extracts and essential oils against Sitophilus oryzae and Callosobruchus chinensis. Journal of Stored products research.; 39 (2003) 293-303.
    18. B. Devi, N.V. Devi, S.N. Singh, The effects of six botanical plant powder extracts on controlling rice weevil, Sitophilusoryzae L. in stored rice grains. International Journal of Agriculture Innovations & Research., 2 (2014) 683-6.
    19. Sighamony, I. Anees, T. Chandrakala, Z. Osmani, Efficacy of certain indigenous plant products as grain protectants against Sitophilus oryzae (L.) and Rhyzopertha dominica (F.). Journal of Stored Products Research., 22 (1986) 21-3.
    20. Karungi, E. Adipala, S. Kyamanywa, M. Ogenga-Latigo, N. Oyobo, L. Jackai, Pest management in cowpea. Part 2. Integrating planting time, plant density, and insecticide application for management of cowpea field insect pests in eastern Uganda. Crop Protection., 19 (2000) 237-45.
    21. Lucas, J. Riudavets, Biological and mechanical control of Sitophilus oryzae (Coleoptera: Curculionidae) in rice. Journal of Stored Products Research., 38 (2002) 293-304.