温度及乳酸链球菌素对单增李斯特菌的抑制作用

Inhibition of temperature and Nisin on Listeria monocytogenes

通过Matlab软件拟合Gompertz生长模型,研究了温度对单增李斯特菌(Listeria.monocytogenes,LM)的影响;同时,研究了不同浓度(5、10、50、100、150μg/m L)、p H(1、3、5、7、9)、温度(45、75、95、115、121℃)条件下的乳酸链球菌素对LM杀菌活性的影响,旨在为LM的监控技术发展提供理论依据。结果表明:低温的抑制效果明显,最大细胞密度减少了4.3455 lg cfu/m L;乳酸链球菌素浓度低于5μg/m L时能促进LM的生长,高于10μg/m L时,对LM有一定的杀菌作用,高于150μg/m L时,48 h之内几乎可以杀死营养肉汤中的所有LM;乳酸链球菌素对酸性有协同效应;并有较好的热稳定性。

The effect of different temperatures on growth of Listeria monocytogenes （LM）was studied, and Gompertz model was fit using Matlab software. In order to provide theory foundation for the development of supervisory technique, the antibacterial activity of Nisin under the different concentrations （5, 10, 50, 100, 150 μg/mL） ,pH（ 1 ,3,5,7,9） and temperatures （45,75,95,115,12] ℃） were studied simultaneously.The results demonstrated that low temperature appeared significantly inhibiting effect,the maximum cell density was reduced by 4.3455 Ig cfu/mL. The growth of LM was promoted when the concentration of Nisin was 〈 5 μg/mL. The bactericidal effects was the concentration of Nisin 〉 10 μg/mL.When the concentration of Nisin was 〉 150 μg/mL,it was able to kill almost all L. rnonocytogenes in nutritional broth during the period of 48 h cultivation. Nisin has a synergistic effect under acidic environment and a good thermal stability.