Data/hora: 05/06/2024 04:35:37

Provedor de dados: | 61
País: | Brazil
Título: | Metabolism of alkaloids in coffee plants
Autores: | Ashihara,Hiroshi.
Data: | 2006-03-01
Ano: | 2006
Palavras-chave: | Coffea; Caffeine; Purine alkaloids; Pyridine alkaloids; Theobromine; Trigonelline.
Resumo: | Coffee beans contain two types of alkaloids, caffeine and trigonelline, as major components. This review describes the distribution and metabolism of these compounds. Caffeine is synthesised from xanthosine derived from purine nucleotides. The major biosynthetic route is xanthosine -&gt; 7-methylxanthosine -&gt; 7-methylxanthine -&gt; theobromine -&gt; caffeine. Degradation activity of caffeine in coffee plants is very low, but catabolism of theophylline is always present. Theophylline is converted to xanthine, and then enters the conventional purine degradation pathway. A recent development in caffeine research is the successful cloning of genes of N-methyltransferases and characterization of recombinant proteins of these genes. Possible biotechnological applications are discussed briefly. Trigonelline (N-methylnicotinic acid) is synthesised from nicotinic acid derived from nicotinamide adenine nucleotides. Nicotinate N-methyltransferase (trigonelline synthase) activity was detected in coffee plants, but purification of this enzyme or cloning of the genes of this N-methyltransferase has not yet been reported. The degradation activity of trigonelline in coffee plants is extremely low.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000100001
Editor: | Brazilian Journal of Plant Physiology
Relação: | 10.1590/S1677-04202006000100001
Formato: | text/html
Fonte: | Brazilian Journal of Plant Physiology  v.18 n.1 2006
Fonte: | info:eu-repo/semantics/openAccess