Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2019

Comparison of the Elution Buffer and Concentration Methods for Detecting Norovirus from Various Foods (#109)

Eun Sook An 1 , Min Hee Jeong 1 , Jeong Su Lee 1 , Jin Hee Hwang 1 , Hyo Sun Kwak 1 , In-Gyun Hwang 1
  1. National Institute of Food and Drug Safety Evaluation, Cheongju, CHUNGBUK, South Korea

Norovirus (NoV) is a leading cause of gastroenteritis outbreaks in human. Common sources of NoV outbreaks include contaminated foods such as fruits, produce and ready-to-eat foods. The detection methods for NoV in various foods are important for preventing and investigating foodborne outbreaks through foods contaminated with NoV. This study aimed to compare the elution buffers and concentration methods for detecting NoV from various foods. Twenty-five gram food samples were artificially inoculated with murine NoV (MNV). Spiking experiment with MNV-1 was conducted to determine the efficiency of viral elution-concentration methods. The inoculated virus on each food was washed using 0.25M threonine-0.3M NaCl (pH 9.5), TGBE (100mM Tris-HCl, 50mM glycine, 3% beef extract (pH 9.5)), 0.25M glycine-0.3M NaCl, Phosphate buffered saline (PBS) and TRIzol reagent. As the next procedure, viral concentration was conducted using polyethylene glycol (PEG) and ultrafiltration (UF). Real-time reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect MNV-1 RNA. The result showed that the recovery rate of the most efficient methods for the elution and concentration was 52.7% for lettuce by TGBE-PEG, 38.3% for cabbage by TGBE-ultrafiltration, 32.3 % for onion by TRIzol, 66.4% for cucumber by TGBE-PEG, 62.1% for tomato by TGBE-PEG, 59.1% for apple by TGBE-ultrafiltration, 71.6% for grape by TGBE-PEG, 24.1% for strawberry by TGBE-ultrafiltration, 68.9% for sesame leaf pickle by TRIzol, 70.0% for pickled radish by TRIzol, 71.8% for salmon by PBS, 72.8% for laver by PBS-PEG, 75.9% for Gimbab by TGBE-ultrafiltration, 37.0% for sandwich by Threonine-ultrafiltration, 38.3% for salad by TGBE-ultrafiltration, 54.8% for a boiled egg by TGBE-ultrafiltration, and 57.3% for raw beef by Glycine. Based on our results, it is concluded that these methods could be practically exploited for detection of NoV in various foods.