Reduction of Enteric Viruses by Blueberry Juice and Blueberry Proanthocyanidins.
Blueberry and blueberry extracts are known for their health benefits and antimicrobial properties. Natural therapeutic or preventive options to decrease the incidences of foodborne viral illnesses are becoming popular and being researched. This study aimed to determine the antiviral effects of blueberry juice (BJ) and blueberry proanthocyanidins (BB-PAC, B-type PAC structurally different from A-type PAC found in cranberries) against the infectivity of hepatitis A virus (HAV) and human norovirus surrogates (feline calicivirus (FCV-F9) and murine norovirus (MNV-1)) at 37 °C over 24 h using standard plaque assays. Viruses at ~5 log PFU/ml were mixed with equal volumes of BJ (pH 2.8), neutralized BJ (pH 7.0), BB-PAC (1, 2, 4, and 10 mg/ml), malic acid (pH 3.0), or phosphate-buffered saline (pH 7.2) and incubated over 24 h at 37 °C. Each experiment was carried out in duplicate and replicated thrice. FCV-F9 titers were found to be reduced to undetectable levels with 1 and 2 mg/ml BB-PAC after 5 min, with 0.5 mg/ml BB-PAC after 1-h, and with BJ after 3-h. MNV-1 titers were reduced to undetectable levels after 3 h with 1, 2, and 5 mg/ml BB-PAC and after 6 h with BJ. HAV titers were reduced to undetectable levels after 30 min with 2 and 5 mg/ml BB-PAC, after 3 h with 1 mg/ml BB-PAC, and by ~2 log PFU/ml with BJ after 24-h. BB-PAC shows preventive potential against infection by the tested enteric viruses in a dose- and time-dependent manner, although further in vitro studies in model food systems and in vivo studies using animal models are warranted.
Department of Food Science and Technology, University of Tennessee, Knoxville, TN, USA.
Snehal S
SS
Joshi
Marucci Center for Blueberry and Cranberry Research, Rutgers, State University of New Jersey, Chatsworth, NJ, USA.
Amy B
AB
Howell
Department of Food Science and Technology, University of Tennessee, Knoxville, TN, USA. ddsouza@utk.edu.
Doris H
DH
D'Souza
D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D029798:Blueberry Plants / Q000737:chemistry*; D017250:Caliciviridae Infections / Q000821:virology*; D005638:Fruit / Q000737:chemistry; D000067030:Fruit and Vegetable Juices / Q000032:analysis*; D006506:Hepatitis A / Q000821:virology*; D030041:Hepatitis A virus / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D029322:Norovirus / Q000187:drug effects* / Q000502:physiology; D010936:Plant Extracts / Q000494:pharmacology*; D044945:Proanthocyanidins / Q000494:pharmacology*
D000998:Antiviral Agents; D010936:Plant Extracts; D044945:Proanthocyanidins
Blueberry (B-type) proanthocyanidins; Blueberry juice; Enteric viruses; Reduction