Krogsgård Nielsen Christina, Kjems Jørgen, Mygind Tina, Snabe Torben, Schwarz Karin, Serfert Yvonne, Meyer Rikke Louise
iNANO, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark.
DuPont Nutrition Biosciences, Edwin Rahrs Vej 38, 8220, Brabrand, Denmark.
Int J Food Microbiol. 2017 Feb 2;242:7-12. doi: 10.1016/j.ijfoodmicro.2016.11.002. Epub 2016 Nov 9.
Food-related biofilms can cause food-borne illnesses and spoilage, both of which are problems on a global level. Essential oils are compounds derived from plant material that have a potential to be used in natural food preservation in the future since they are natural antimicrobials. Bacterial biofilms are particularly resilient towards biocides, and preservatives that effectively eradicate biofilms are therefore needed. In this study, we test the antibacterial properties of emulsion-encapsulated and unencapsulated isoeugenol against biofilms of Lis. monocytogenes, S. aureus, P. fluorescens and Leu. mesenteroides in tryptic soy broth and carrot juice. We show that emulsion encapsulation enhances the antimicrobial properties of isoeugenol against biofilms in media but not in carrot juice. Some of the isoeugenol emulsions were coated with chitosan, and treatment of biofilms with these emulsions disrupted the biofilm structure. Furthermore, we show that addition of the surfactant Tween 80, which is commonly used to disperse oils in food, hampers the antibacterial properties of isoeugenol. This finding highlights that common food additives, such as surfactants, may have an adverse effect on the antibacterial activity of preservatives. Isoeugenol is a promising candidate as a future food preservative because it works almost equally well against planktonic bacteria and biofilms. Emulsion encapsulation has potential benefits for the efficacy of isoeugenol, but the effect of encapsulation depends on the properties of food matrix in which isoeugenol is to be applied.
与食物相关的生物膜会导致食源性疾病和食物变质，这两个问题在全球范围内都存在。精油是从植物材料中提取的化合物，由于它们是天然抗菌剂，因此未来有可能用于天然食品保鲜。细菌生物膜对杀菌剂具有特别强的抵抗力，因此需要能有效根除生物膜的防腐剂。在本研究中，我们测试了乳液包封和未包封的异丁香酚对胰蛋白胨大豆肉汤和胡萝卜汁中单核细胞增生李斯特菌、金黄色葡萄球菌、荧光假单胞菌和肠系膜明串珠菌生物膜的抗菌性能。我们发现乳液包封增强了异丁香酚在培养基中对生物膜的抗菌性能，但在胡萝卜汁中却没有。一些异丁香酚乳液用壳聚糖包被，用这些乳液处理生物膜会破坏生物膜结构。此外，我们还发现，食品中常用的用于分散油相的表面活性剂吐温80会削弱异丁香酚的抗菌性能。这一发现突出表明，常见的食品添加剂，如表面活性剂，可能会对防腐剂的抗菌活性产生不利影响。异丁香酚作为未来的食品防腐剂是一个有前景的候选物，因为它对浮游细菌和生物膜的作用几乎同样有效。乳液包封对异丁香酚的功效可能有好处，但包封效果取决于异丁香酚所应用的食品基质的特性。
