Antiviral Effect of Lithium Chloride and Diammonium Glycyrrhizinate on Porcine Deltacoronavirus In Vitro

Zhai, Xiaofeng; Wang, Shilei; Zhu, Mengyan; He, Wei; Pan, Zhongzhou; Su, Shuo

The cytotoxicity of LiCl and DG was assessed in vitro using the Cell Counting Kit-8 (CCK8, APE×BIO, Houston, TX, USA) according to the manufacturer's instructions. LLC-PK1 cells were seeded into 96-cell plates and grown to 100% confluence for 24 h. After washing three times with PBS, the cells were treated with increasing concentrations of LiCl ranging from 0 to 100 mM or DG ranging from 50 to 5000 µg/mL. Mock-treated cells served as a control. After 36 h, the cells were washed with PBS and incubated with 90 µL DMEM and 10 µL of CCK-8 solution at 37 • C for 2 h. Absorbance was measured with a microplate reader (Tecan, M200 PRO, CH) at 450 nm. Cytotoxicity was expressed according to the following formula: Cytotoxicity(%) = (Abs sample) − (Abs blank) (Abs negative control) − (Abs blank) × 100