Anti-viral Activity Of The Four Monomers Of Isatis Tinctoria L.against Coxsackievirus B3 And Adenovirus In Vitro

Objective: Screen the antiviral activity of the four monomers of Isatis tinctoria L. (No.6, 7, 8, and9) on Adenovirus and Coxsackievirus B₃ in vitro.Methods: In these experiments, virazole was used as positive control. Antiviral activity were investigated by observing cytopathic effect (CPE), by using MTT colorimetric assay for viable cell rate, by detecting CVB₃-RNA using semi-quantitative RT-PCR and testing viral titers, by using plaque reduction test and compounding the four monomers in HEp-2 cells. And the treatment index (TI=TC₅0/IC₅0) was utilized as a comprehensive criterion to assess the effects of the compounds.Results:1 All of the four monomers of Isatis tinctoria L. could inhibit the biosynthesis of CVB₃ in vitro. The anti- CVB₃ IC₅0 were 91.45, 169.5, 152.4, 242.1μg/mL respectively. The anti-CVB3 of the four monomers had no difference. And the antiviral activity of the four monomers is better than the virazole at the same doseage level (P>0.05). But the treatment index of No.8 was higher than others (P<0.05). This means it has the lowest toxicity to cell but can inhibit CVB3 more effectively. There are obvious dosage-effect relationship between the 3.9-500μg/mL dose of the four monomers and the anti- CVB3 inhibitory rate in vitro(.P<0.05). It was found as the dose of the drugs increased, the degree of CPE decreased but the viral inhibition rate increased.2 , All of the four monomers of Isatis tinctoria L. could inactivate the biosynthesis of AdV in vitro. The anti-AdV IC₅0 were572.57, 65.38, 58.16, 71.78μg/mL respectively. The anti- AdV of No. 6 was better than others. And the antiviral activity of the four monomers is better than the virazole at the same doseage level (P>0.05). But the treatment index of No.8 was higher than others (P<0.05). This means it has the lowest toxicity to cell but can inactivate AdV more effectively. There are obvious dosage-effect relationship between the 3.9-500μg/mL doses of the four monomers and the anti-AdV inhibitory rate in vitro(T<0.05). It was found as the dose of the compounds increased, the degree of CPE decreased but the viral inhibition rate increased.3^he four monomers of Isatis tinctoria L. could inhibit the biosynthesis of Adenovirus and Coxsackievirus B3 in vitro. But anti- Adenovirus and Coxsackievirus B3 of the treatment index of No.8 was higher than others (PO.05). The toxicity of No.8 was lowest than others, the antivirus effect was better than others.4> The compound of the the four monomers of Isatis tinctoria L. could inhibit the biosynthesis of Adenovirus in vitro.5>The antiviral activity of the four monomers of Isatis tinctoria L. (No.6, 7, 8, and9) on Adenovirus in vitro were interactional. The interactional compound of the four monomers were No.6 and No.7; No.6 and No.9; No.6 and No.7 and No.8; No.6 and No.8and No.9. The antiviral activities of these compounds were better than anyone of the four monomers (P<0.05).Conclusion:1, The four monomers (No.6, 7, 8, and9) were the valid distill antiviral component of Isatis tinctoria L..2^ The four monomers of Isatis tinctoria L. could inactivate the biosynthesis of CVB3 and Adenovirus in vitro.AI No.8 are found to be the most effective anti-CVB3 monomer, thus its respective component can be used to further purify the most active chemical monomers.3> The antiviral activities of the four monomers of Isatis tinctoria L. (No.6, 7, 8, and9) on Adenovirus in vitro were interactional.