Kouakou Privat, Ghalfi Hakim, Destain Jacqueline, Duboisdauphin Robin, Evrard Pol, Thonart Philippe
Faculté Universitaire des Sciences Agronomiques de Gembloux, 2 Passage des Déportés, B-5030 Gembloux, Belgium.
Meat Sci. 2008 Nov;80(3):640-8. doi: 10.1016/j.meatsci.2008.02.015. Epub 2008 Feb 26.
This work focused on Listeria monocytogenes growth inhibition and growth rebound in raw and cooked pork meat inoculated with Lactobacillus curvatus strains. During storage of raw meat homogenates in the presence of the bacteriocin-producing strain Lactobacillus curvatus CWBI-B28wt, the Listeria monocytogenes cfu count was initially reduced to an undetectable level, but a growth rebound occurred after two weeks, coinciding with loss of 70% of the bacteriocin activity present at the end of week 2. The Listeria growth rebound was suppressed when proteolysis of bacteriocin was countered by the absence of proteases (bacteriocin addition to cooked meat) or the presence of 1% soy flour (added to provide competing substrates). Further experiments confirmed that bacteriocin is sensitive to the action of proteolytic enzymes isolated from both Lactobacillus curvatus CWBI-B28wt and the meat matrix. Bacteriocin proteolysis thus emerges as a cause of Listeria growth rebound.
这项工作聚焦于用弯曲乳杆菌菌株接种的生猪肉和熟猪肉中单核细胞增生李斯特菌的生长抑制及生长反弹情况。在含有产细菌素的弯曲乳杆菌CWBI - B28wt的生肉匀浆储存期间，单核细胞增生李斯特菌的菌落形成单位（cfu）计数最初降至检测不到的水平，但两周后出现生长反弹，这与第2周结束时存在的细菌素活性丧失70%同时发生。当通过不存在蛋白酶（向熟肉中添加细菌素）或存在1%大豆粉（添加以提供竞争性底物）来对抗细菌素的蛋白水解时，李斯特菌的生长反弹受到抑制。进一步的实验证实，细菌素对从弯曲乳杆菌CWBI - B28wt和肉基质中分离出的蛋白水解酶的作用敏感。因此，细菌素的蛋白水解成为李斯特菌生长反弹的一个原因。
