Abstract:

Objective: To establish the optimal enrichment and RNA extraction procedures for detecting hepatitis A virus
(HAV) in strawberries. Methods: After artificial contamination of known negative samples, HAV enrichment under
optimized conditions and RNA extraction were performed for analysis by real-time fluorescence PCR. Results: The virus
was enriched by elution with Tris glycine 1 g/100 mL beef extract buffer (TGBE), removal of the inhibitors using 30 U of
pectinase and a mixture of chloroform with n-butanol, precipitation with PEG, and 1 h incubation at 5 ℃. The detection
method was sensitive. The best RNA extraction results were achieved with a RNA extraction kit from ABI. The
sensitivity of the optimized method for detecting HAV particles was 31.36 CCID50/20 g of sample. Negative results
were reported for all 50 samples tested. Conclusion: The established method is suitable for the detection of HAV in
strawberry samples with high sensitivity.

Key words: strawberry, hepatitis A virus, virus enrichment, RNA extraction