Thymol

Thymol (also known as 2-isopropyl-5-methylphenol, IPMP) is a natural monoterpene phenol derivative of cymene, C₁₀H₁₄O, isomeric with carvacrol, found in oil of thyme, and extracted from Thymus vulgaris (common thyme) and various other kinds of plants as a white crystalline substance of a pleasant aromatic odor and strong antiseptic properties. Thymol also provides the distinctive, strong flavor of the culinary herb thyme, also produced from T. vulgaris.

Biological activity

Thymol is part of a naturally occurring class of compounds known as biocides, with strong antimicrobial attributes when used alone or with other biocides such as carvacrol. In addition, naturally occurring biocidal agents such as thymol can reduce bacterial resistance to common drugs such as penicillin. Numerous studies have demonstrated the antimicrobial effects of thymol, ranging from inducing antibiotic susceptibility in drug-resistant pathogens to powerful antioxidant properties. Research demonstrates that naturally occurring biocides such as thymol and carvacrol reduce bacterial resistance to antibiotics through a synergistic effect, and thymol has been shown to be an effective fungicide, particularly against fluconazole-resistant strains. This is especially relevant given that opportunistic Candida fungal infections can cause severe systemic infections in immunocompromised patients, and current treatments are highly toxic, often result in drug-resistant Candida strains, and have low efficacy. Compounds in the essential oils of one type of oregano have demonstrated antimutagenic effects, and in particular carvacrol (isomeric with thymol) and thymol were demonstrated to have a strong antimutagenic effect. In addition, there is evidence that thymol has antitumor properties. Though the exact mechanism is unknown, some evidence suggests thymol effects at least some of its biocidal properties by membrane disruption.