Antibacterial activity of the leaf essential oil of Chuc (Citrus hystrix) from Vietnam: In silico and In vitro approaches

Abstract

Citrus hystrix is a highly valued commercial plant in Vietnam, widely used in culinary and medicinal practices. Although its traditional applications are well established, the antibacterial properties and mechanisms of its leaf essential oil (COL), particularly from plants cultivated in Vietnam, remain insufficiently explored. In this study, we investigated the antibacterial activity of COL using both in silico and in vitro approaches. Previous chemical profiling identified citronellol, citronellal, linalool, and nerolidol as the dominant constituents of COL. Molecular docking simulations demonstrated considerable binding affinities of these constituents with three key enzymes related to bacterial survival and antibiotic resistance such as DNA gyrase, PBP2a, and PBP-4 with binding energies ranging from -4.2 to -6.0 kcal/mol. These computational results were supported by minimum inhibitory concentration (MIC) assays, which showed COL antibacterial activity against Pseudomonas aeruginosa, Yersinia enterocolitica, Staphylococcus aureus, and Enterococcus faecium (MIC range: 0.61–2.43 mg/mL). The antibacterial effect was primarily bactericidal against Y. enterocolitica, S. aureus, and E. faecium, whereas P. aeruginosa exhibited tolerance with no detectable minimum bactericidal concentration. Collectively, these findings highlight the potential of COL as a source of antibacterial agents, warranting further mechanistic and pharmacological investigations.