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Updated: Jun 8, 2026

Caffeine Extraction, Enzymatic Activity and Gene Expression of Caffeine Synthase from Plant Cell Suspensions
Published on: October 2, 2018
Distribution, biosynthesis and catabolism of methylxanthines in plants
Hiroshi Ashihara1, Misako Kato, Alan Crozier
1Department of Biological Sciences, Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan. ashihara.hiroshi@ocha.ac.jp
Abstract:
Methylxanthines and methyluric acids are purine alkaloids that are synthesized in quantity in a limited number of plant species, including tea, coffee and cacao. This review summarizes the pathways, enzymes and related genes of caffeine biosynthesis. The main biosynthetic pathway is a sequence consisting of xanthosine → 7-methylxanthosine → 7-methylxanthine → theobromine → caffeine. Catabolism of caffeine starts with its conversion to theophylline. Typically, this reaction is very slow in caffeine-accumulating plants. Finally, the ecological roles of caffeine and the production of decaffeinated coffee plants are discussed.
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