Field Des, Daly Karen, O'Connor Paula M, Cotter Paul D, Hill Colin, Ross R Paul
Department of Microbiology, University College Cork, Cork, Ireland
Department of Microbiology, University College Cork, Cork, Ireland.
Appl Environ Microbiol. 2015 Apr;81(8):2762-9. doi: 10.1128/AEM.00070-15. Epub 2015 Feb 6.
The food-borne pathogenic bacterium Listeria is known for relatively low morbidity and high mortality rates, reaching up to 25 to 30%. Listeria is a hardy organism, and its control in foods represents a significant challenge. Many naturally occurring compounds, including the bacteriocin nisin and a number of plant essential oils, have been widely studied and are reported to be effective as antimicrobial agents against spoilage and pathogenic microorganisms. The aim of this study was to investigate the ability of semipurified preparations (SPP) containing either nisin A or an enhanced bioengineered derivative, nisin V, alone and in combination with low concentrations of the essential oils thymol, carvacrol, and trans-cinnamaldehyde, to control Listeria monocytogenes in both laboratory media and model food systems. Combinations of nisin V-containing SPP (25 μg/ml) with thymol (0.02%), carvacrol (0.02%), or cinnamaldehyde (0.02%) produced a significantly longer lag phase than any of the essential oil-nisin A combinations. In addition, the log reduction in cell counts achieved by the nisin V-carvacrol or nisin V-cinnamaldehyde combinations was twice that of the equivalent nisin A-essential oil treatment. Significantly, this enhanced activity was validated in model food systems against L. monocytogenes strains of food origin. We conclude that the fermentate form of nisin V in combination with carvacrol and cinnamaldehyde offers significant advantages as a novel, natural, and effective means to enhance food safety by inhibiting food-borne pathogens such as L. monocytogenes.
食源致病菌李斯特菌以发病率相对较低但死亡率较高而闻名，死亡率可达25%至30%。李斯特菌是一种顽强的微生物，对其在食品中的控制是一项重大挑战。许多天然存在的化合物，包括细菌素乳酸链球菌素和多种植物精油，已得到广泛研究，并据报道可作为抗腐败和致病微生物的抗菌剂。本研究的目的是调查含有乳酸链球菌素A或增强型生物工程衍生物乳酸链球菌素V的半纯化制剂（SPP）单独以及与低浓度的精油百里香酚、香芹酚和反式肉桂醛联合使用时，在实验室培养基和模拟食品体系中控制单核细胞增生李斯特菌的能力。含乳酸链球菌素V的SPP（25μg/ml）与百里香酚（0.02%）、香芹酚（0.02%）或肉桂醛（0.02%）的组合产生的迟缓期比任何精油-乳酸链球菌素A组合都显著更长。此外，乳酸链球菌素V-香芹酚或乳酸链球菌素V-肉桂醛组合实现的细胞计数对数减少是同等的乳酸链球菌素A-精油处理的两倍。重要的是，这种增强的活性在模拟食品体系中针对食品源单核细胞增生李斯特菌菌株得到了验证。我们得出结论，乳酸链球菌素V的发酵产物与香芹酚和肉桂醛联合使用，作为一种通过抑制食源性病原体如单核细胞增生李斯特菌来提高食品安全的新型、天然且有效的手段，具有显著优势。
