Ecological significance Flavonoids

HARBORNE, J.B., Flavonoid sulfates A new class of natural products of ecological significance in plants, in Progress in Phytochemistry, Vol. 4 (L. Reinhold, J.B. Harbome, T. Swain, eds.). Pergamon Press, New York. 1977, pp. 189-208. 

There are two major classes of natural products primary and secondary metabolites. Primary metabolites are compounds that exist in all organisms and are involved in basal and vital metabolism (e.g., glucose, fatty acids, amino acids, etc.). Secondary metabolites, alkaloids, terpenoids, and flavonoids, are unique to a particular species and vary in their basic structures. Secondary metabolites are usually accumulated, as most of their end metabolites are in plants, but are excreted in animals and microorganisms and some of these are proven to have pharmacological and ecological significance. 

Kajiyama, K. et al., Flavonoids and isoflavonoids of chemotaxonomic significance from Glycyr-rhiza pallidiflora (Leguminosae), Biochemical Systematics and Ecology, 21, 785, 1993. 

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