Changes in content and biosynthetic activity of caffeine and trigonelline during growth and ripening of Coffea arabica and Coffea canephora fruits

摘要: Caffeine and trigonelline are major nitrogenous alkaloids found in coffee seeds. Accumulation of these two cultivars Coffea arabica a cultivar canephora seeds was monitored. Growth stages specified by letters, A to G. They correspond the pinhead small (A), rapid expansion pericarp growth (B), endosperm formation (C), early dry matter accumulation (D), mature (green) (E), ripening (pink) (F) fully ripened (red) (G) stages. content increased at D E. The concentrations caffeine ripe (stage G) C. were respectively 1.0% 1.9% weight. high biosynthetic activity caffeine, which estimated via incorporation [8-14C]adenine into purine alkaloids, whole fruits (perisperm pericarp) B C, developing (endosperm) activities reduced both F In cv. Mokka canephora, transcripts CmXRS1, CTS2 CCS1, three N-methyltransferase genes for biosynthesis, methionine synthase gene (MS) detected every stage growth, although amounts significantly less pattern expression synthesis during is roughly related situ from adenine nucleotides, exceptions very later fruit growth. CCS1 higher than pericarp, but reverse true MS fruits. Similarly, (N3-methyltransferase) also pericarp. Concentrations Mokka, Catimor ca. 1.3%, 1.4% weight, respectively. High young (stages A–C) E). markedly These results suggest that active biosynthesis occurs Although final concentration varies plants, patterns fluctuations all plants similar.