Chemical composition, antimicrobial activity and antiviral activity of essential oil of Carum copticum from Iran

Evaluation of therapeutic effects of Carum copticum (C. copticum) has been the subject of several studies in recent years. Thymol the major component of C. copticum is a widely known anti-microbial agent. In this study, the antibacterial and anti viral activities of essential oil of C. copticum fruit were determined. Essential oil of C. copticum was analyzed by means of gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity of the oil was evaluated against six Gram (+/-) bacteria and fungi, using the micro broth dilution technique. Antiviral activity of the essential oil was evaluated using a Bacillus phage CP51. From the ten identified constituents, representing 98.7% of the oil, thymol (72.3%), terpinolene (13.12%) and o-cymene (11.97%) were the major components. It was found that the oil exhibited strong antimicrobial activity against Staphylococcus aureus (S. aureus) and Bacillus subtilis (B. subtilis) (MIC, 0.00025% v/v). Furthermore, the antiviral activity of the oil was evaluated by plaque reduction assay. The essential oil showed an antiviral activity against phage when phage was pre-incubated with the essential oil prior to its exposure to B. cereus and without any pre-incubation with the phage, suggesting that the oil directly inactivated virus particles.