Essential oils as nature-engineered antifungals: a comprehensive review of pharmacological mechanisms, drug synergism, and advanced formulation strategies

Essential Oils (EOs) and their active compounds are more effective than traditional antifungal drugs. They are effective against a wide range of pathogens and can neutralise multiple targets simultaneously. Fungal resistance development is minimised due to multi-target effects. EOs that are rich in phenols and terpenoids are derived from plants such as Cinnamomum , Thymus , Origanum , and Syzygium . These compounds act against fungal pathogens, namely, Candida , Aspergillus , and dermatophyte fungi. They function by disrupting cell membranes and inhibiting ergosterol biosynthesis in fungi. Oxidative stress also plays a significant role in this context. When antifungal agents such as amphotericin B and fluconazole are combined with active compounds in EOs, they create synergy, increasing the efficacy of the active compounds while reducing the drug dose. This decreases the toxicity of the drugs. In recent days, new drug manufacturing processes, such as nano emulsions and natural deep eutectic solvents, have emerged, thereby increasing the stability of volatile compounds in EOs. This increases the drug’s solubility, thereby enhancing its absorption. This review highlights the mechanisms by which EOs act against fungi, the mechanisms involved, and their compatibility with other treatments.