Metabolism of Caffeine and Related Purine Alkaloids in Leaves of Tea (Camellia sinensis L.)
スポンサーリンク
概要
- 論文の詳細を見る
Purine alkaloid catabolism pathways in young, mature and aged leaves of tea (Camellia sinensis L.) were investigated by incubating leaf sections with ^<14>C-labelled theobromine, caffeine, theophylline and xanthine. Incorporation of label into CO_2 Was determined and methanol-soluble metabolites were analysed by high-performance liquid chronratography-radiocounting and thin layer chromatography. The data obtained demonstrate that theobromine is the immediate precursor of caffeine, which accumulates in tea leaves because its conversion to theophylline is the rate limiting step in the purine alkaloid catabolism path-way. The main fate of [8-^<14>C]theophylline incubated with mature and aged leaves, and to a lesser extent young leaves, is conversion to 3-methylxanthine and onto xanthine which is degraded to ^<14>CO_2 via the purine catabolism pathway. However, with young leaves, sizable amounts of [8-^<14>C]-theophylline were salvaged for the synthesis of caffeine via a 3-methylxanthine → theobromine → caffeine pathway. Trace amounts of [2-^<14>C]xanthine were also salvaged for caffeine biosynthesis in young leaves, by conversion to 3-methylxanthine, and this was enhanced in the presence of 5 mM allopurinol which inhibits purine catabolism. Feeds of [2-^<14>C]xanthine to young leaves also indicated that 3-methylxanthine, as well as being salvaged for theobromine and caffeine production, is also converted, via N-1-methylation, to theophylline.
- 日本植物生理学会の論文
著者
-
Ashihara Hiroshi
Department of Biology, Faculty of Science, Ochanomizu University
-
Ashihara Hiroshi
Department Of Advanced Biosciences Graduate School Of Humanities And Sciences Ochanomizu University
-
Gillies Fiona
Bower Building Division Of Biochemistry And Molecular Biology Institute Of Biomedical And Life Scien
-
Crozier A
Univ. Glasgow Glasgow Gbr
-
Crozier Alan
Bower Building, Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life sci
関連論文
- Biosynthesis of Purine Alkaloids in Camellia Plants
- Transcatheter arterial infusion chemotherapy with cisplatin-lipiodol suspension in patients with hepatocellular carcinoma
- Metabolic Alterations in Organic Acids and γ-Aminobutyric Acid in Developing Tomato (Solanum lycopersicum L.) Fruits
- Biochemical Mechanism on GABA Accumulation During Fruit Development in Tomato
- The mechanism of changes in respiratory activity during callus formation in carrot root slices cultured in vitro
- Regulation of Cytoplasmic pH under Extreme Acid Conditions in Suspension Cultured Cells of Catharanthus roseus : a Possible Role of Inorganic Phosphate
- Metabolism of Caffeine and Related Purine Alkaloids in Leaves of Tea (Camellia sinensis L.)
- Changes in Levels and Rates of Biosynthesis of Amino Acids during the Growth of Catharanthus roseus Cells in Batch Suspension Culture
- WOUND RESPIRATION AND NUCLEOTIDE BIOSYNTHESIS IN POTATO (Solanum tuberosum) TUBER SLICES
- Metabolism of Aromatic Amino Acids during the Growth Cycle of Batch Suspension Cultures of Catharanthus roseus
- Optical Emission Spectroscopy of Arc Flame Plasma for Generation of Carbon Nanotubes
- Purine Alkaloid Biosynthesis in Young Leaves of Camellia sinensis in Light and Darkness
- Nucleotide Pools and Purine Metabolism in Tissue Cultures of Wild-Type Datura innoxia and Adenine-Requiring Auxotroph
- Long-Term Phosphate Starvation and Respiratory Metabolism in Suspension-Cultured Catharanthus roseus Cells
- Evidence for Deposition of Cellulose Prior to Dark-starvation Treatment During Spherulation in Physarum microplasmodia
- Profiles of Purine Metabolism in Leaves and Roots of Camellia sinensis Seedlings
- Biosynthesis and Metabolism of Purine Alkaloids in Leaves of Cocoa Tea(Camellia ptilophylla)
- A Case of Ectopic Adrenocorticotropic Hormone-producing Pancreatic Neuroendocrine Tumor with Multiple Liver Metastases
- Pyridine metabolism in tea plants : salvage, conjugate formation and catabolism