Purine Alkaloids of the Fruits of Camellia sinensis L. and Coffea arabica L. during Fruit Development*

Abstract

The amounts of two purine alkaloids, caffeine and theobromine, in the fruit of tea ( Camellia sinensis L.) increased markedly during the growing season until the fruit was full-ripened and dried. In the dry fruit, the pericarp contained the most alkaloids, but there were also considerable amounts in the seed coat and, to a lesser extent, the fruit stalk and the seed. The shed seeds also contained significant amounts of the alkaloids, especially in the seed coats. In contrast with the dry fruit of tea, seeds and pericarp of coffee ( Coffea arabica L.) fruit contained a considerable amount of caffeine and a small amount of theobromide. A small amount of theophylline was also present in the pericarp of the ripened fruit. Relationships between growth and purine alkaloid content in tea and coffee fruits and their roles during seed formation are discussed.