Antibacterial efficacy of Trachyspermum ammi Oil against Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans: An in vitro study

Background: Ajwain (Trachyspermum ammi) oil is used widely because of its nutritional value, antioxidant and antibacterial activity against various microorganisms, but there are no studies that relate the antibacterial activity of Ajwain oil against periodontal pathogens. Aim: To evaluate and compare the minimum inhibitory concentration (MIC) and zone of inhibition of T. ammi (Ajwain seed) oil and 0.2% chlorhexidine gluconate against Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans through serial tube dilution and disc diffusion methods. Materials and Methods: An in vitro study was conducted. Ajwain oil (100%) and chlorhexidine solution (0.2%) were purchased. Blood agar media with hemin, Vitamin K and Kanamycin, crystal violet erythromycin blood agar, and thioglycolate broth with 1% horse serum were used to culture P. gingivalis, F. nucleatum, and A. actinomycetemcomitans, respectively. The MIC and minimum bactericidal concentration of test agents were assessed using the serial dilution method, and the zone of inhibition was assessed by the Agar disc diffusion method. Results: Ajwain oil had the ability to exert antibacterial activity against P. gingivalis, F. nucleatum, and A. actinomycetemcomitans at a MIC of 0.4, 0.4, and 0.8 μg/ml, respectively. Ajwain oil exerted bactericidal effect against P gingivalis, F. nucleatum, and A. actinomycetemcomitans at a minimum concentration of 0.4, 0.4, and 6.25 μg/ml, respectively, and bacteriostatic effect at a minimum concentration of 0.2, 0.2, and 3.12 μg/ml, respectively. At 50% μg/ml concentration, Ajwain oil exhibited a higher zone of inhibition compared to chlorhexidine against P. gingivalis, F. nucleatum, and A. actinomycetemcomitans. Conclusion: Ajwain oil demonstrated antibacterial effect against periodontal pathogens in vitro.