Biological and Agricultural Engineering, Univ. of California, Davis, Davis, CA, 95616, U.S.A.
Food Science and Technology, Univ. of California, Davis, One Shields Ave, Davis, CA, 95616, U.S.A.
J Food Sci. 2018 Jul;83(7):1871-1879. doi: 10.1111/1750-3841.14188. Epub 2018 Jun 15.
There is a significant unmet need to develop antimicrobial solutions to reduce the risk of contamination in fresh produce. Bacteriophages have been proposed as a potential approach for controlling foodborne pathogens. This study evaluated the combination of edible dip coatings with T7 bacteriophages on whole and cut produce. The evaluation includes an assessment of phage loading, phage storage stability, antimicrobial activity, and phage stability during simulated gastric digestion on sliced cucumbers, sliced apples, and whole cherry tomatoes. In this evaluation, phages coated on fresh produce using edible whey protein isolate (WPI) were compared with phages coated from an aqueous suspension (control coating). The results demonstrated that WPI coatings load more phages than the control and enhanced phage stability during cold storage (4 °C) for cut apples and whole cherry tomatoes. Phage stability decreased by 1 to 3 log(PFU) in a simulated gastric environment. Phage antimicrobial activity against Escherichia coli BL21 decreased 2 to 4 log(CFU) of bacteria on cut apples and whole cherry tomatoes, while no significant bacterial reduction was observed for sliced cucumbers. Overall, the results show that WPI dip coating provides phage loading, stability, and antimicrobial activity to produce surfaces compared to the control coating, and thus may be considered an effective approach for extending phage therapy on fresh produce.
The practical application is to prevent bacterial cross contamination of fresh produce by using a combination of edible coating with bacteriophages. The results demonstrate enhanced loading and stability of phages on fresh produce when used in combination with an edible coating.
开发抗菌解决方案以降低新鲜农产品污染风险的需求巨大。噬菌体已被提议作为控制食源性病原体的一种潜在方法。本研究评估了可食用浸渍涂层与 T7 噬菌体在整体和切片农产品上的结合。该评估包括对噬菌体负载量、噬菌体储存稳定性、抗菌活性以及模拟胃液消化过程中噬菌体在切片黄瓜、切片苹果和整颗樱桃番茄上的稳定性进行评估。在这项评估中，使用可食用乳清蛋白分离物 (WPI) 涂覆在新鲜农产品上的噬菌体与涂覆在水性悬浮液中的噬菌体 (对照涂层) 进行了比较。结果表明，WPI 涂层比对照涂层负载更多的噬菌体，并增强了冷藏（4°C）过程中切割苹果和整颗樱桃番茄中噬菌体的稳定性。噬菌体在模拟胃液环境中的稳定性下降了 1 到 3 个对数（PFU）。噬菌体对 BL21 大肠杆菌的抗菌活性在切割苹果和整颗樱桃番茄上降低了 2 到 4 个对数（CFU）的细菌，而在切片黄瓜上则没有观察到明显的细菌减少。总体而言，结果表明，与对照涂层相比，WPI 浸渍涂层为农产品表面提供了噬菌体负载、稳定性和抗菌活性，因此可能被认为是在新鲜农产品上扩展噬菌体疗法的有效方法。
通过使用抗菌涂层与噬菌体的组合来防止新鲜农产品的细菌交叉污染。结果表明，在与可食用涂层结合使用时，噬菌体在新鲜农产品上的负载和稳定性得到增强。
