Fig. 2

Maintenance of viral inactivation activity of GTE. a-c Maintenance of viral inactivation activity of GTE solution. 0.01, 0.05, and 0.1% GTE solutions were stored at 4 °C (a), 25 °C (b), and 37 °C (c), and 0.001% GTE was incubated at 25 °C. The GTE solutions incubated for different time points were mixed with 10⁶ PFU of PR8 virus and further incubated for six h at 25 °C for viral inactivation. Residual viral titers were determined by plaque assay on MDCK cells. d Maintenance of viral inactivation activity of GTE powder. GTE powder was stored for 1 − 16 weeks at 25 °C, and then dissolved in distilled water to make 0.1% GTE solutions. The GTE solutions were incubated with 10⁶ PFU of PR8 virus for six h at 25 °C for viral inactivation. Residual viral titers were determined by plaque assay on MDCK cells. As a control, the virus was incubated with PBS under the same conditions, and the viral titer was indicated by upper dashed lines. Data are the mean of two independent experiments. Detection limit of plaque assay is 5, and error bars indicate the standard deviation (SD)