Nguyen V T, Gidley M J, Dykes G A
School of Land and Food Sciences, University of Queensland, St. Lucia, Qld., Australia.
Food Microbiol. 2008 May;25(3):471-8. doi: 10.1016/j.fm.2008.01.004. Epub 2008 Jan 29.
A bacterially produced cellulose film containing nisin was developed and used in a proof-of-concept study to control Listeria monocytogenes and total aerobic bacteria on the surface of vacuum-packaged frankfurters. Bacterial cellulose pellicles were produced by Gluconacetobacter xylinus K3 in Corn Steep Liquor-Mannitol Medium and were subsequently purified before nisin was incorporated into them. Investigations into the effect of nisin concentrations and contact times on incorporation of nisin into cellulose films showed that the lowest nisin concentration and shortest time needed for production of an effective antimicrobial cellulose film were 625IUml(-1) and 6h, respectively. The active cellulose films produced under these conditions did not, however, significantly reduce L. monocytogenes populations on frankfurters (P>0.05) during refrigerated storage for 14 days as compared to the controls. Films produced using a higher concentration of nisin (2500IUml(-1)) with the same exposure time (6h) resulted in a significant (P<0.05) decrease in L. monocytogenes counts on frankfurters of approximately 2logCFUg(-1) after 14 days of storage as compared to the control. Both the above-mentioned films showed a similar effectiveness in reducing total aerobic bacterial populations as measured by total aerobic plate counts on frankfurters. For both films, total aerobic bacterial levels were significantly (P>0.05) reduced by approximately 3.3logCFUg(-1) after 14 days of storage as compared to control samples. Bacterial cellulose films were demonstrated in this study to have potential applicability as antimicrobial packaging films or inserts for processed meat products.
开发了一种含有乳酸链球菌素的细菌生产纤维素膜，并将其用于一项概念验证研究，以控制真空包装法兰克福香肠表面的单核细胞增生李斯特菌和总需氧菌。木醋杆菌K3在玉米浆-甘露醇培养基中生产细菌纤维素薄膜，随后在将乳酸链球菌素掺入其中之前进行纯化。对乳酸链球菌素浓度和接触时间对其掺入纤维素膜效果的研究表明，生产有效抗菌纤维素膜所需的最低乳酸链球菌素浓度和最短时间分别为625IUml(-1)和6小时。然而，在这些条件下生产的活性纤维素膜在冷藏储存14天期间，与对照组相比，并未显著降低法兰克福香肠上的单核细胞增生李斯特菌数量（P>0.05）。使用较高浓度乳酸链球菌素（2500IUml(-1)）并在相同暴露时间（6小时）下生产的薄膜，与对照组相比，储存14天后法兰克福香肠上的单核细胞增生李斯特菌数量显著（P<0.05）减少了约2logCFUg(-1)。上述两种薄膜在通过法兰克福香肠上的总需氧平板计数测量减少总需氧细菌数量方面显示出相似的效果。对于这两种薄膜，与对照样品相比，储存14天后总需氧细菌水平均显著（P>0.05）降低了约3.3logCFUg(-1)。本研究证明细菌纤维素膜作为抗菌包装膜或用于加工肉类产品的插入物具有潜在的适用性。
