Inhibitory Activity of Scutellaria baicalensis Flavonoids against Tick-Borne Encephalitis Virus

Bull Exp Biol Med. 2020 Mar;168(5):665-668. doi: 10.1007/s10517-020-04776-y. Epub 2020 Apr 4.


We studied virus-inhibiting activity of Baikal skullcap (Scutellaria baicalensis) flavonoids against tick-borne encephalitis virus using various model schemes. The half-maximum cytotoxic concentration (CC50) for the plant extract was found (363.9±58.6 μg/ml). Based on the CC50 and IC50, selective index (SI) was calculated for viricidal (53.4), preventive (50.5), and direct antiviral actions (39.1) and for-intracellular replication of the virus (40.4). Suppression of virus reproduction ≥2.0 lg TCID50 was observed at extract concentration ≥5 μg/ml (viricidal effect), ≥11.2 μg/ml (preventive and direct antiviral effects), and ≥9 μg/ml (intracellular replication). Flavonoids of Baikal skullcap extract produced an in vitro inhibitory effect on tick-borne encephalitis virus due to their direct viricidal activity and direct inhibition of adsorption and intracellular replication of tick-borne encephalitis virus, which determines their value as highly effective antiviral drugs.

Keywords: Baikal skullcap; inhibition; tick-borne encephalitis virus (TBEV).

MeSH terms

  • Animals
  • Antiviral Agents / isolation & purification
  • Antiviral Agents / pharmacology
  • Cells, Cultured
  • Dose-Response Relationship, Drug
  • Embryo, Mammalian
  • Encephalitis Viruses, Tick-Borne / drug effects*
  • Encephalitis Viruses, Tick-Borne / physiology
  • Encephalitis, Tick-Borne / pathology
  • Encephalitis, Tick-Borne / virology
  • Flavonoids / isolation & purification
  • Flavonoids / pharmacology*
  • Models, Theoretical
  • Plant Extracts / pharmacology*
  • Scutellaria baicalensis / chemistry*
  • Swine / embryology
  • Virus Replication / drug effects


  • Antiviral Agents
  • Flavonoids
  • Plant Extracts
  • Scutellaria baicalensis extract