da Silva Luz Isabelle, Gomes-Neto Nelson Justino, Magnani Marciane, de Souza Evandro Leite
Laboratory of Food Microbiology, Department of Nutrition, Health Sciences Center, Federal University of Paraíba, João Pessoa, Brazil.
Laboratory of Microbiological Processes in Foods, Department of Food Engineering, Center of Technology, Federal University of Paraíba, João Pessoa, Brazil
Food Sci Technol Int. 2015 Dec;21(8):571-80. doi: 10.1177/1082013214554467. Epub 2014 Oct 7.
This study assessed the efficacy of Origanum vulgare L. essential oil (OVEO) and carvacrol in inhibiting the growth of Pseudomonas aeruginosa ATCC 9027, as well as the development of direct tolerance and cross-tolerance when this bacterium was challenged with sublethal amounts of these substances in a meat-based broth and in a meat model. OVEO and carvacrol at their minimum inhibitory concentrations (MICs), 1/2 MIC and 1/4 MIC decreased the viable cell counts of P. aeruginosa in meat-based broth. Direct tolerance or cross-tolerance was not induced after exposure of the assayed bacterial strain to sublethal amounts of OVEO or carvacrol in meat-based broth and in an artificially contaminated ground beef. Bacterial cells progressively subcultured in meat-based broth with increasing amounts of the tested substances survived up to the MIC of OVEO and to 1/2 MIC of carvacrol. The results reveal a lack of induction of tolerance in P. aeruginosa by exposure to OVEO or carvacrol in meat-based broth and in a meat model.
本研究评估了牛至精油(OVEO)和香芹酚对铜绿假单胞菌ATCC 9027生长的抑制效果,以及当该细菌在肉汁培养基和肉类模型中受到亚致死量的这些物质刺激时直接耐受性和交叉耐受性的发展情况。在肉汁培养基中,处于最低抑菌浓度(MIC)、1/2 MIC和1/4 MIC的OVEO和香芹酚降低了铜绿假单胞菌的活菌数。在肉汁培养基和人工污染的碎牛肉中,将受试菌株暴露于亚致死量的OVEO或香芹酚后,未诱导出直接耐受性或交叉耐受性。在含有逐渐增加量受试物质的肉汁培养基中连续传代培养的细菌细胞,存活至OVEO的MIC和香芹酚的1/2 MIC。结果表明,在肉汁培养基和肉类模型中,铜绿假单胞菌暴露于OVEO或香芹酚不会诱导耐受性。