Figure 1. Antiviral activity of morin hydrate against A/PR/8 and oseltamivir-resistant influenza A virus in vitro. A549 cells were infected with 1×10³ pfu of A/PR/8 (A, B) or oseltamivir-resistant influenza A virus (C, D) and incubated with oseltamivir carboxylate and/or morin hydrate at the indicated concentrations for 48 h. Cell viability was determined using SRB assay. (E) Western blotting to detect NP in A/PR/8-infected and non-infected A549 cells after 24 h-treatment with vehicle or 250 μM of morin hydrate. (F) The ratios of NP to β-actin levels based on the quantification of the bands in the immunoblot shown in (E). (G) A549 cells were infected with 1×10³ pfu of A/PR/8, and harvested at the indicated time points after treatment with 250 µM morin hydrate or 10 µM oseltamivir carboxylate. Total RNA was isolated and expression levels of viral PA RNA was analyzed using RT-qPCR. Data are expressed as the mean±SEM of the values from three independent experiments.

^*p<0.05, ^**p<0.01 and ^***p<0.001 based on the ANOVA with Bonferroni's multiple comparison test.