Oral epithelial cells were inoculated with HSV-1 strain 17+ (MOI = 0.05) in the presence of
the indicated concentration of blackberry extract. Following cell adsorption at 37°C and two
rinses with PBS, fresh cell culture media containing the indicated concentration of
blackberry extract was added and incubation was continued overnight at 37°C. Twenty four
hours post inoculation, cells were freeze-thawed 3 times and virus yield was quantified on
Vero cell monolayers by the direct plaque assay. Data represents the average +/− SD of
triplicate replication assays (i.e. n = 3). *, p < 0.005.