[Note: enteroviruses are a large family of viruses that infect through the gastrointestinal tract, the most common of which cause some 5 million annual bouts with gastroenteritis or upper respiratory illness in the US each year.]
Grape Seed Extract (GSE) is reported to have many pharmacological benefits, including antioxidant, anti-inflammatory, anticarcinogenic, and antimicrobial properties.
However, the effect of this inexpensive rich source of natural phenolic compounds on human enteric viruses has not been well documented.
In the present study, the effect of commercial GSE, Gravinol-S, on the infectivity of human enteric virus surrogates:
• (Feline calicivirus, FCV-F9;
• Murine norovirus, MNV-1; [“noroviruses cause most of the non-bacterial food-borne gastroenteritis in humans”]
• And bacteriophage MS2)
• And hepatitis A virus (HAV; strain HM175)
GSE at concentrations of 0.5, 1, and 2 mg/ml was individually mixed with equal volumes of each virus at titers [concentrations] of ~7 log(10) PFU/ml or ~5 log(10) PFU/ml and incubated for 2 hours at room temperature or 37°C [98° Fahrenheit].
The infectivity of the recovered viruses after triplicate treatments was evaluated by standardized plaque assays. At high titers (~7 log(10) PFU/ml), FCV-F9 was significantly reduced by 3.64, 4.10, and 4.61 log(10) PFU/ml; MNV-1 by 0.82, 1.35, and 1.73 log(10) PFU/ml; MS2 by 1.13, 1.43, and 1.60 log(10) PFU/ml; and HAV by 1.81, 2.66, and 3.20 log(10) PFU/ml after treatment at 37°C with 0.25, 0.50, and 1 mg/ml GSE, respectively (P < 0.05) in a dose-dependent manner.
GSE treatment of low titers (~5 log(10) PFU/ml) at 37°C also showed viral reductions.
Room-temperature treatments with GSE caused significant reduction of the four viruses, with higher reduction for low-titer FCV-F9, MNV-1, and HAV compared to high titers.
Our results indicate that Grape Seed Extract shows promise for application in the food industry as an inexpensive novel natural alternative to reduce viral contamination and enhance food safety.
Source: Applied and Environmental Microbiology, Jun 2011;77(12):3982-7. PMID:21498749, by Su X, D'Souza DH. Department of Food Science and Technology, University of Tennessee-Knoxville, Knoxville, Tennessee, USA. [Email: firstname.lastname@example.org]