Arsenal for survival: secondary plant products

Summary Harborne, J. B.: Arsenal for survival: secondary plant products. ‐ Taxon 49: 435–449. 2000.‐ISSN 0040‐0262. The rise and fall over the first fifty years of plant chemosystematics, employing secondary products, is outlined here. The retention of some degree of activity in this field is recommended, especially with the flavonoids that are of universal occurrence. This is not only to further refine systems of plant classification below the family level, but also to map the still largely uncharted territory of bioactive metabolites in plants. Almost every plant species has a unique collection of secondary constituents distributed throughout its tissues, a proportion of which is likely to respond positively to an appropriate medical bioassay. The success of the chemosystematic approach to the search for a renewable source of taxol, the anti‐cancer drug from Taxus brevifolia , is described.