Evaluation of antiviral effect and toxicity of total flavonoids extracted from Robinia pseudoacacia cv. idaho

[Display omitted] •Total flavonoids from Robinia pseudoacacia cv. idaho (RPTF) was extracted by 70% ethanol.•RPTF have significant inhibitory effects on HSV-1 and EV-71 viruses.•Long-term high doses group of RPTF may cause a decrease in appetite and affect weight gain in rats.•RPTF is a promising traditional natural-based antiviral therapeutic with relative safety in use. In this study, we aimed to evaluate the antiviral effect of total flavonoids extracted from Robinia pseudoacacia cv. idaho (RPTF) in vivo and its toxicity on rats with oral gavage. RPTF was prepared by percolation with 70% ethanol for 24 h and its antiviral effect on different kinds of viruses was evaluated in vitro by MTT staining. The long-term toxicity of RPTF on rats was evaluated through the detection of general behavior, body weight, food intake and related organ tissue sections of experimental animals. We found that RPTF produced significantly inhibitory effects on HSV-1 and EV-71 viruses with the therapeutic index TI values 113.8 and 46.2, respectively. Moreover, toxicity evaluation in vivo showed no significantly adverse effects in rats, indicating that RPTF was safe in use. In conclusion, we demonstrated that RPTF, natural compounds in the Chinese traditional medicine, could act as promising and effective antiviral therapeutics with relative safety in use.