Figure 1Structure of sakuranetin isolated from Sorbus commixta.
Figure 2Antiviral activity of sakuranetin against human rhinovirus (HRV) 3 in human epithelioid carcinoma cervix (HeLa) cells. Antiviral activity of the three extracts against HRV3 in HeLa cells is shown; (A) Antiviral activity of sakuranetin against HRV3 in HeLa cells. (B) Cytotoxicity of sakuranetin in HeLa cells. The diluted virus suspension, containing 30 mM MgCl2, 1% fetal bovine serum, and 50% tissue culture infective dose of the virus, was added to HeLa cells to produce the appropriate cytopathic effect (CPE) within 48 hours after infection. The antiviral activity and cytotoxicity of sakuranetin were investigated through the sulforhodamine B (SRB) assay with CPE reduction. Results are presented as the mean percentage values obtained from three independent experiments performed in triplicate ± standard deviation.
Figure 3The effect of sakuranetin on human rhinovirus (HRV) 3-induced cytopathic effect (CPE). The effects of sakuranetin on HRV3-induced CPE are shown. Culture medium in 96-well tissue culture plates was aspirated and the cells were washed with phosphate buffered saline. Thereafter, 0.09 mL of the diluted virus suspension, containing 30 mM MgCl2, 1% fetal bovine serum, and 50% tissue culture infective dose of the virus and 0.01 mL of medium were added to human epithelioid carcinoma cervix (HeLa) cells to produce the appropriate CPE within 48 hours after infection, and then sakuranetin or ribavirin (100 mg/mL) was added. After incubation at 32°C and 5% CO2 for 2 days, the cells stained by SRB, and cellular morphology was studied using photographs taken under a light microscope (×400). (A) Non-infected cells; (B) HRV3-infected cells without sakuranetin or ribavirin treatment; (C) non-infected cells treated with sakuranetin; (D) virus-infected cells treated with sakuranetin; (E) non-infected cells with treated ribavirin; (F) virus-infected cells treated with ribavirin.