Antibacterial activity of essential oil extracted from Citrus hystrix (Kaffir Lime) peels: An in vitro study

摘要

The exploration of antimicrobial activities from various herbal plants such asCitrus species might be a solution to reduce the emergency of antimicrobial resistance.This study was conducted to determine the chemical composition of Citrus hystrix essentialoil (CHEO) and its antibacterial activity against a broad range of Gram positive and Gramnegative bacteria. CHEO was extracted from the peels of kaffir lime by steam distillation.The chemical composition was analyzed by gas chromatography-mass spectrometry (GCMS).In vitro antibacterial activity was determined by the agar disk diffusion and brothmacrodilution methods against 6 standard bacterial strains as well as 39 clinical bacterialisolates. GC-MS revealed twenty-seven compounds in CHEO with most predominantcompounds like; D-limonene, followed by β-pinene and sabinene. CHEO had inhibitoryeffects on all tested bacterial isolates except for Klebsiella pneumoniae, Salmonellaparatyphi A, Salmonella enteritidis, Edwardsiella tarda and Pseudomonas aeruginosa.Gram positive bacteria were generally more susceptible than Gram negative bacteria(ranged MIC; 1.0-8.0 mg/mL vs. 8.0 to 16.0 mg/mL) with Staphylococcus aureus andElizabethkingia meningoseptica being the most susceptible. These findings demonstratedthat CHEO has a potential to be developed as an antibacterial agent to combat the emergingantimicrobial resistant bacteria.