Metabolic (Catabolic) Modifications of Alkaloids by Plants

Abstract

The study of alkaloid biosynthesis has been a major effort of natural products chemists, biochemists, and pharmaceutical chemists during the past several decades. Alkaloid catabolism studies have been a minor effort of a small group of scientists, some of whom are oriented primarily toward botany or plant physiology. As Robinson (1974) states, “Alkaloids appear to be active metabolites, but their usefulness to plants remains obscure.” It is incorrect to conclude that the problem of metabolism has been solved merely because the routes of biosynthesis have been described; the other half of the problem is what happens to the alkaloid after it is synthesized. Catabolic reactions of some alkaloids have been studied using microorganisms (especially soil microorganisms), and biochemical pharmacology has yielded data on modifications of alkaloids which may be interpreted as detoxification processes in animals. Altschul (1970, 1973) recently completed a study of 2.5 million specimens of flowering¹ plants that have been described as restorative of health, according to medicinal folklore. Altschul (1970) and Schultes (1975a,b) indicate that many species offer, somewhat vaguely, hope for relief of cancer, heart disease, mental illness, and diverse metabolic disorders, but these authors have not yet explored the plants influencing the function and diseases of the reproductive tract of the human female.

This chapter was written by George R. Waller, L. Skursky of the University of J. E. Purkijne, Brno, Czechoslovakia, and T. M. Heinze of the Medical Research Foundation, Oklahoma City, Oklahoma.