Table 1.

Effect of grape seed extract (GSE) against feline calicivirus (FCV-F9), murine norovirus (MNV-1), MS2 bacteriophage, and hepatitis A virus (HAV) at both high (∼7-log10-PFU) and low (∼5-log10-PFU) titers after 2 h of incubation at 37°C or room temperaturea

VirusTreatment37°CRoom temp
High titer (log10 PFU/ml)Low titer (log10 PFU/ml)High titer (log10 PFU/ml)Low titer (log10 PFU/ml)
Recovered titerReductionRecovered titerReductionRecovered titerReductionRecovered titerReduction
FCV-F9Water6.93 ± 0.17 A04.98 ± 0.08 A06.99 ± 0.16 A05.01 ± 0.06 A0
0.25 mg/ml GSE3.29 ± 0.35 B3.640.00 ± 0.00 B4.984.21 ± 0.21 B2.780.00 ± 0.00 B5.01
0.5 mg/ml GSE2.83 ± 0.73 B4.100.00 ± 0.00 B4.983.69 ± 0.06 BC3.300.00 ± 0.00 B5.01
1 mg/ml GSE2.32 ± 0.63 B4.610.00 ± 0.00 B4.983.19 ± 0.30 C3.800.00 ± 0.00 B5.01
MNV-1Water6.93 ± 0.12 A04.82 ± 0.09 A06.86 ± 0.07 A04.86 ± 0.06 A0
0.25 mg/ml GSE6.11 ± 0.18 B0.823.33 ± 0.42 AB1.496.42 ± 0.12 B0.443.49 ± 0.22 B1.37
0.5 mg/ml GSE5.58 ± 0.21 BC1.353.10 ± 0.64 B1.726.14 ± 0.08 B0.723.38 ± 0.37 B1.48
1 mg/ml GSE5.20 ± 0.32 C1.732.85 ± 0.67 B1.975.80 ± 0.21 C1.063.19 ± 0.38 B1.67
MS2Water7.04 ± 0.08 A05.17 ± 0.02 A07.14 ± 0.05 A05.15 ± 0.06 A0
0.25 mg/ml GSE5.91 ± 0.18 B1.133.82 ± 0.08 B1.356.11 ± 0.13 B1.034.12 ± 0.08 B1.03
0.5 mg/ml GSE5.61 ± 0.24 B1.433.65 ± 0.12 B1.526.05 ± 0.12 B1.093.99 ± 0.13 B1.16
1 mg/ml GSE5.44 ± 0.33 B1.603.32 ± 0.13 C1.855.48 ± 0.13 C1.663.99 ± 0.18 B1.16
HAVWater6.67 ± 0.04 A05.26 ± 0.12 A06.59 ± 0.04 A05.25 ± 0.07 A0
0.25 mg/ml GSE4.86 ± 0.16 B1.813.40 ± 0.13 B1.865.73 ± 0.10 B0.862.85 ± 0.09 B2.40
0.5 mg/ml GSE4.01 ± 0.09 C2.663.00 ± 0.09 C2.265.37 ± 0.05 C1.222.63 ± 0.09 C2.62
1 mg/ml GSE3.47 ± 0.07 D3.202.37 ± 0.17 D2.894.69 ± 0.13 D1.902.24 ± 0.11 D3.01
  • a Each treatment was replicated three times, and plaque assays for evaluating the infectivity of the viruses were carried out in duplicate. Within each column for each virus, different letters denote significant differences between treatments (P < 0.05). At P < 0.01, only low-titer MNV-1 reduction after GSE treatment at 37°C and only high-titer MNV-1 reduction by 0.25-mg/ml GSE treatment at room temperature were not significantly different.