Essential oils for controlling multidrug-resistant pathogens in livestock: bridging in-vitro data to phytogenic additives

Abstract

Antibiotic resistance is a pressing global crisis fueled by overuse in medicine, farming, and agriculture, producing superbugs like MRSA (Methicillin-resistant Staphylococcus aureus) and extended-spectrum-lactamase (ESBL) E. coli, causing prolonged and untreatable infections. Essential oils (EO) provide a natural alternative, offering broad-spectrum antibacterial potency with reduced risk of rapid resistance. Present study assessed the antimicrobial efficacy of 71 essential oils against 144 clinical bacterial isolates by determining their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) as compared with 14 standard antibiotics. Twelve EOs such as thyme, holy basil, lemon grass, cinnamon, oregano, rosewood, cassia, rose, clove, palmrosa, carom seeds and betel leaf showed remarkable potency. Out of 12 Eos, thyme, cinnamon, cassia, oregano and carom seeds were found to be most effective and categorized as strong while holy basil, lemongrass, rosewood, palmrosa, rose, clove and betel leaf were considered as moderate effective EOs. Notably, oregano achieved the lowest MIC (0.039 μL) against E. coli and the lowest MBC (0.156 μL) against Klebsiella pneumoniae. EOs demonstrates powerful antibacterial effects against multidrug-resistant pathogens, frequently surpassing conventional antibiotics in efficacy. Judicious use of these natural oils as feed additives can effectively contribute to the livestock health.