Go toArchive
Browse byFacets
Bookbag ( 0 )
'14C L Phenylalanine' in keywords
Results  1 Item
Sorted by   
Section
Publication Year
1985 (1)
1Author    U. Margna, L. Laanest, E. Margna, T. VainjärvRequires cookie*
 Title    L-Tyrosine as a Precursor of Flavonoids in Buckwheat Cotyledons  
 Abstract    Exogenous L-tyrosine was incorporated 1 3 -1 4 tim es less effectively than exogenous L-phenyl-alanine into flavonoids in excised cotyledons o f 3 days old buckw heat seedlings but proved to be an only 5 times poorer precursor when the experim ents were carried out with 5 days old material. Simultaneous administration o f L-phenylalanine m arkedly reduced incorporation o f L-tyrosine into flavonoids. A similar decrease in the utilization o f exogenous L-tyrosine for flavonoid b io­ synthesis occurred in kinetin-treated cotyledons. H owever, in cotyledons treated with high doses o f glyphosate, an inhibitor o f the shikim ic acid pathway, an increase in the formation o f flavonoids from exogenously supplied L-tyrosine was observed. Under all conditions the relative incorporation rate o f exogenous L-tyrosine was highest for anthocyanins and lowest for C-glyco-sylflavones while within the latter class o f com pounds the luteolinic derivatives orientin and iso-orientin incorporated more label than their apigeninic analogues vitexin and isovitexin. PAL and TAL activities were found to be present in the cotyledons in a ratio o f 50:1. The possible role o f L-tyrosine as an alternative natural precursor for the biosynthesis o f flavonoids and other related polyphenols is discussed. 
  Reference    Z. Naturforsch. 40c, 154 (1985); received April 24/O ctober 29 1984 
  Published    1985 
  Keywords    Anthocyanins, Flavonoids, Biosynthesis, [14C-L]Tyrosine, [14C-L]Phenylalanine, Kinetin, Glyphosate, Fagopyrum esculentum 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/40/ZNC-1985-40c-0154.pdf 
 Identifier    ZNC-1985-40c-0154 
 Volume    40