Saponin components exhibit antiviral properties against porcine epidemic diarrhea virus <i>in vitro</i>

Piglets afflicted with porcine epidemic diarrhea virus (PEDV) experience severe diarrhea and elevated death rates, leading to substantial financial losses in the pig farming sector. The objective of this study is to investigate the impact of saponins on PEDV within Vero cells by utilizing different methodologies to evaluate their anti-PEDV effect. By producing 40 saponins, we have discovered that No. 29, No. 31, No. 35, and No. 38 exhibit properties that make them effective against PEDV, serving as potential drugs. The findings showed that in a clear dose-dependent manner, the mRNA levels of PEDV were significantly inhibited in the high, middle, and low-dose groups of No. 29, No. 31, No. 35, and No. 38, when compared to the PEDV control. The four tested saponins significantly inhibited the levels of PEDV N contents and viral titers. Furthermore, concentration of cytotoxicity 50% (CC₅₀) values for No. 29, No. 31, No. 35, and No. 38 saponins were 37.13 μM, 52.86 μM, 44.98 μM, and 43.81 μM, respectively, demonstrating the safety of these medications in clinical environments. Collectively, these findings indicate that the four examined saponins could efficiently modulate the immune response against PEDV and hold promise for utilization in antiviral treatments.