ABSTRACT
The authors have barely scraped the bark in their efforts to exploit the plant world for antiviral compounds. Plant resources are unlimited, as far as the search for useful phytochemicals is concerned. Identification and final purification of a bioactive phytochemical is a job for a chemist and final confirmation requires laboratory synthesis of the proposed structure and verification of its activity. In India, there are several pharmaceutical preparations, consisting of one or more crude plant materials, for the treatment of several kinds of hepatitis. Antiviral activity could also "disappear" during the course of fractionation and repeated extractions, and this could be due to masking, sequestering by another compound, dilution, or loss of protective substances, or real inactivation. It is conceivable that success in the future may come from custom-designed antivirals that work on unique features of individual viruses, but this will clearly require numerous designer antivirals, preceded by much time and expensive research.
