Bouttefroy A, Mansour M, Linder M, Milliere J B
Laboratoire de Fermentations et de Bioconversions Industrielles, Institut National Polytechnique de Lorraine, Ecole Nationale Supérieure d'Agronomie et des Industries Alimentaires (ENSAIA-INPL) 2, Vandoeuvre-Les-Nancy, France.
Int J Food Microbiol. 2000 Mar 10;54(1-2):109-15. doi: 10.1016/s0168-1605(99)00171-3.
The influence of pH (5.0-8.2), NaCl concentrations (0-6% w/v), and incubation time (0-24 h) on the inhibitory activity of nisin (0-100 I.U./ml) against Listeria monocytogenes (10(3) cfu/ml) was studied using the Doehlert experimental design and was confirmed by kinetic experiments. Predicted values were in agreement with experimental values. Experiments were carried out at 22 degrees C in reconstituted TSB-YE1 broth with or without NaCl. Nisin had an immediate pH-dependent bactericidal effect, which increased with decreasing pH values. In modified TSB-YE1 broth without NaCl, the bactericidal efficacy of nisin (50 I.U./ml) was maximum at pH 6.6, with no L. monocytogenes survivors until 120 h at 22 degrees C. Nisin (50 I.U./ml) action decreased in the presence of NaCl, with a minimal inhibitory effect between 2 and 4%. This partially protective effect was cancelled at higher levels of nisin.
采用Doehlert实验设计研究了pH值（5.0 - 8.2）、NaCl浓度（0 - 6% w/v）和孵育时间（0 - 24 h）对乳酸链球菌素（0 - 100国际单位/毫升）抑制单核细胞增生李斯特菌（10³ 菌落形成单位/毫升）活性的影响，并通过动力学实验进行了验证。预测值与实验值相符。实验在22℃下于添加或不添加NaCl的复溶胰酪大豆胨酵母浸出液（TSB - YE1）肉汤中进行。乳酸链球菌素具有直接的pH依赖性杀菌作用，随着pH值降低而增强。在不含NaCl的改良TSB - YE1肉汤中，乳酸链球菌素（50国际单位/毫升）在pH 6.6时杀菌效果最佳，在22℃下120小时内无单核细胞增生李斯特菌存活。在有NaCl存在时，乳酸链球菌素（50国际单位/毫升）的作用减弱，在2%至4%之间有最小抑制作用。在较高浓度的乳酸链球菌素作用下，这种部分保护作用被消除。
