Plant Essential Oils and Their Active Ingredients: Antifungal and Therapeutic Potential

The search for plant-based anti-infective products in combating infectious diseases has gained appreciable impetus in recent years, particularly due to the increased cases of fungal diseases in immunocompromised patients. Furthermore, the development of resistance to common antifungal drugs complicates the treatment. This has triggered the need to look for alternative treatment strategies through the use of natural products exhibiting minimal toxicity, bioavailability, and broad-spectrum efficacy against fungal pathogens. Among the plethora of plant products, essential oils like thyme oil, clove oil, cinnamon oil, oregano oil, tea tree oil, and their active compounds offer significant antimicrobial activity, prompting exploration into their antifungal therapeutic potential. Essential oils have demonstrated significant antifungal efficacy against many important fungal pathogens, including Candida, Aspergillus, Cryptococcus, and Dermatophytes. Attempts have been made to evaluate their in- vitro and in- vivo efficacies, safety, and bioavailability. This chapter explores the recent advances in the field of antifungal drug discovery, with special focus on antifungal and therapeutic potential of essential oils and/or their active ingredients. We discuss the mechanism of action of such compounds, the progress of in- vitro examination of their activity, in- vivo efficacy, improved formulations, and probable barriers in successful therapeutic applications in the struggle against fungal infections.