HSV-1 strain 17+ was added to oral epithelial cells at an MOI = 0.05 and allowed to adsorb
and enter for 1 hr at 37°C. Fresh cell culture media, containing the indicated concentration
of blackberry extract, was added and incubation was continued overnight, followed by two
PBS rinses. 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.