Imamura Saiki, Kanezashi Hiromi, Goshima Tomoko, Suto Atsushi, Ueki You, Sugawara Naoko, Ito Hiroshi, Zou Bizhen, Uema Masashi, Noda Mamoru, Akimoto Keiko
1 Food Safety and Consumer Affairs Bureau, Ministry of Agriculture Forestry and Fisheries , Tokyo, Japan .
2 Miyagi Prefectural Government , Sendai, Japan .
Foodborne Pathog Dis. 2017 Sep;14(9):518-523. doi: 10.1089/fpd.2017.2294. Epub 2017 Jun 8.
The contamination of oysters with human noroviruses poses a human health risk, since oysters are often consumed raw. In this study, human norovirus genogroup II was allowed to bio-accumulate in oysters, and then the effect of high-pressure processing (HPP) on human noroviruses in oysters was determined through a polymerase chain reaction (PCR)-based method with enzymatic pretreatment to distinguish infectious noroviruses. As a result, oysters could be artificially contaminated to a detectable level of norovirus genome by the reverse transcription-PCR. Concentrations of norovirus genome in laboratory-contaminated oysters were log normally distributed, as determined by the real-time PCR, suggesting that artificial contamination by bio-accumulation was successful. In two independent HPP trials, a 1.87 log and 1.99 log reduction of norovirus GII.17 genome concentration was observed after HPP at 400 MPa for 5 min at 25°C. These data suggest that HPP is a promising process of inactivation of infectious human noroviruses in oysters. To our knowledge, this is the first report to investigate the effect of HPP on laboratory-contaminated noroviruses in oysters.
人类诺如病毒污染牡蛎会对人类健康构成风险，因为牡蛎常常生食。在本研究中，让人类诺如病毒II基因组在牡蛎中进行生物累积，然后通过基于聚合酶链反应（PCR）并采用酶预处理以区分感染性诺如病毒的方法，来测定高压处理（HPP）对牡蛎中人类诺如病毒的影响。结果，通过逆转录PCR可将牡蛎人工污染至诺如病毒基因组的可检测水平。通过实时PCR测定，实验室污染牡蛎中诺如病毒基因组的浓度呈对数正态分布，这表明通过生物累积进行的人工污染是成功的。在两项独立的HPP试验中，在25°C下400 MPa处理5 min后，观察到诺如病毒GII.17基因组浓度分别降低了1.87对数和1.99对数。这些数据表明，HPP是一种很有前景的灭活牡蛎中感染性人类诺如病毒的方法。据我们所知，这是首篇研究HPP对实验室污染的牡蛎中诺如病毒影响的报告。
