Direct virucidal activity of baicalein against DENV-2. Foci forming unit reduction assay was used to determine the direct anti-dengue virus activity of the baicalein. Baicalein was added directly to virus inoculum prior to infecting cells (A) and the respective DENV-2 RNA copies were quantified using qRT-PCR (B). All experiments were conducted in triplicates. The percentages of foci reduction (%RF) and RNA copy number reduction were obtained by comparing against the controls maintained in parallel.