ANTIMICROBIAL POTENTIAL OF CLOVE (SYZYGIUM AROMATICUM), CINNAMON (CINNAMOMUM VERUM), AND LEMON (CITRUS LIMON) ESSENTIAL OILS: MECHANISMS, APPLICATIONS, AND FUTURE PERSPECTIVES

Nandani Thakur*, Priya Rani, Daisy Sharma, Khushbu Chandel, Mainka Devi

The rapid emergence of antimicrobial resistance (AMR) has become a major global health concern, reducing the effectiveness of conventional antimicrobial therapies and increasing the burden of infectious diseases. Consequently, there is growing interest in alternative antimicrobial agents derived from natural sources. Essential oils, complex mixtures of volatile bioactive compounds produced by aromatic plants, have attracted considerable scientific attention because of their broad-spectrum antimicrobial activity, biodegradability, and relatively low propensity for inducing microbial resistance. Among the numerous plant-derived essential oils, clove (Syzygium aromaticum), cinnamon (Cinnamomum verum), and lemon (Citrus limon) essential oils are particularly noteworthy because of their potent antibacterial, antifungal, antioxidant, and antibiofilm properties. This review summarizes current knowledge regarding the chemical composition, antimicrobial mechanisms, and therapeutic potential of these three essential oils. The major bioactive constituents, including eugenol, cinnamaldehyde, and limonene, are discussed in relation to their antimicrobial activities against bacterial and fungal pathogens. Particular emphasis is placed on their activity against multidrug-resistant microorganisms, biofilm-forming pathogens, and healthcare-associated infections. Recent advances in nanoencapsulation, synergistic combinations with conventional antibiotics, and emerging pharmaceutical applications are also highlighted. Furthermore, current limitations, safety considerations, and future research directions are critically evaluated. Available evidence suggests that clove, cinnamon, and lemon essential oils possess significant antimicrobial potential and may serve as valuable complementary agents in combating antimicrobial resistance. Continued research focusing on standardization, formulation development, mechanistic studies, and clinical validation is required to facilitate their successful translation into therapeutic and industrial applications.