Fino Viviana R, Kniel Kalmia E
Department of Animal and Food Sciences, University of Delaware, 044 Townsend Hall, 531 South College Avenue, Newark, Delaware 19716-2150, USA.
J Food Prot. 2008 May;71(5):908-13. doi: 10.4315/0362-028x-71.5.908.
A majority of illnesses caused by foodborne viruses are associated with fresh produce. Fruits and vegetables may be considered high-risk foods, as they are often consumed raw without a specific inactivation step. Therefore, there is a need to evaluate nonthermal treatments for the inactivation of foodborne pathogens. This study investigates the UV inactivation of three viruses: feline calicivirus (a surrogate for norovirus), and two picornaviruses, hepatitis A virus and Aichi virus. Three produce types were selected for their different surface topographies and association with outbreaks. Green onions, lettuce, and strawberries were individually spot inoculated with 10(7) to 10(9) 50% tissue culture infective doses (TCID50) of each virus per ml and exposed to UV light at various doses (< or = 240 mW s/cm2), and viruses were eluted using an optimized recovery strategy. Virus infection was quantified by TCID50 in mammalian cell culture and compared with untreated recovered virus. UV light applied to contaminated lettuce resulted in inactivation of 4.5 to 4.6 log TCID50/ml; for contaminated green onions, inactivation ranged from 2.5 to 5.6 log TCID50/ml; and for contaminated strawberries, inactivation ranged from 1.9 to 2.6 log TCID50/ml for the three viruses tested. UV light inactivation on the surface of lettuce is more effective than inactivation on the other two produce items. Consistently, the lowest results were observed in the inactivation of viruses on strawberries. No significant differences (P > 0.05) for virus inactivation were observed among the three doses applied (40, 120, and 240 mW s/cm2) on the produce, with the exception of hepatitis A virus and Aichi virus inactivation on green onions, where inactivation continued at 120 mW s/cm2 (P < 0.05).
大多数食源性病毒引起的疾病与新鲜农产品有关。水果和蔬菜可能被视为高风险食品，因为它们通常未经特定的灭活步骤就直接生食。因此，有必要评估用于灭活食源性病原体的非热处理方法。本研究调查了三种病毒的紫外线灭活情况：猫杯状病毒（诺如病毒的替代物）以及两种小RNA病毒，甲型肝炎病毒和爱知病毒。选择了三种农产品，因其表面形貌不同且与疫情爆发有关。分别将每毫升含有10⁷至10⁹个50%组织培养感染剂量（TCID₅₀）的每种病毒点接种到青葱、生菜和草莓上，并使其暴露于不同剂量（≤240 mW s/cm²）的紫外线下，然后使用优化的回收策略洗脱病毒。通过在哺乳动物细胞培养中测定TCID₅₀来量化病毒感染情况，并与未处理的回收病毒进行比较。施加于受污染生菜上的紫外线导致4.5至4.6 log TCID₅₀/ml的灭活率；对于受污染的青葱，灭活率范围为2.5至5.6 log TCID₅₀/ml；对于受污染的草莓，在所测试的三种病毒中，灭活率范围为1.9至2.6 log TCID₅₀/ml。生菜表面的紫外线灭活比其他两种农产品更有效。一致地，在草莓上病毒灭活的结果最低。在所施加的三种剂量（40、120和240 mW s/cm²）下，除了甲型肝炎病毒和爱知病毒在青葱上的灭活情况外，农产品上病毒灭活情况未观察到显著差异（P>0.05），在青葱上，120 mW s/cm²时灭活仍在继续（P<0.05）。
