EFFECTS OF CRUDE EXTRACTS OF VARIOUS PLANTS ON INFECTIOUS BOVINE-RHINOTRACHEITIS VIRUS-PLAQUE PRODUCTION

  • 1 January 1976
    • journal article
    • research article
    • Vol. 37  (2) , 215-218
Abstract
Extracts of 28 plants were tested without demonstrable antiviral activity in an agar-overlay plaque-reduction antiviral assay system, using infectious bovine rhinotracheitis virus and bovine endocardial cell cultures. Ethanolic extract of Narcissus tazetta bulb elicited antiviral activity by inhibition of viral plaque formation. Antiviral activity was demonstrated against infectious bovine rhinotracheitis and equine rhinopneumonitis viruses. N. tazetta bulb did not directly inactivate the virus extracellularly. The extract exhibited only limited toxicity to rapidly multiplying bovine endocardial cells at plaque-inhibitory levels and was not cytotoxic to preformed confluent cell monolayers. Narcissus extract did not induce the formation of drug-resistant viral strains.