FIG 2.

Delphinidin and its conversion products are all active against HCVcc. (A) Toxicity of delphinidin was quantified in Huh-7 cells. Huh-7 cells were cultured in the presence of the delphinidin concentrations shown. Their viability was monitored with an MTS-based viability assay after 24, 48, and 72 h. Data are expressed as a ratio with respect to the control, i.e., the condition without delphinidin. Error bars represent the SEM from three independent experiments performed in triplicate. (B) Delphinidin at 50 μM in HEPES buffer was incubated at 37°C, and the optical density at 596 nm was determined every 5 min. (C) Delphinidin was preincubated or not for 1 h at 37°C in culture medium. Huh-7 cells were infected with the virus in the presence of increasing concentrations of freshly dissolved (circles) or preincubated (squares) delphinidin. Infected cells were quantified by immunofluorescence assay. Data are normalized to the DMSO control, which is expressed as 100% infection. Data are the mean value ± SEM obtained in three independent experiments performed in triplicate.