Identification of a Major Cytokinin in Coconut Milk

Experientia. 1995 Nov 15;51(11):1081-4. doi: 10.1007/BF01946921.


A major cytokinin found in coconut milk was isolated by using the tobacco callus growth-promoting assay as a guide during purification. The structure of the factor was determined to be 14-O-(3-O-[beta-D-galactopyranosyl-(1-->2)-alpha-D-galactopyranosyl-(1-- >3)- alpha-L-arabinofuranosyl]-4-O-(alpha-L-arabinofuranosyl)-beta-D- galactopyranosyl)-trans-zeatin riboside [G3A2-ZR] by various NMR techniques, including heteronuclear multiple bond connectivity by 2D multiple quantum NMR (HMBC), as well as mass spectroscopy and sugar analysis. The optimum concentration of G3A2-ZR for cytokinin activity in the tobacco callus assay was estimated to be 5 x 10(-6) M, so that G3A2-ZR is one order of magnitude more potent than 1,3-diphenylurea and one order less potent than zeatin riboside. At least 20% of the cytokinin activity of coconut milk could be attributed to G3A2-ZR.

MeSH terms

  • Carbohydrate Conformation
  • Carbohydrate Sequence
  • Cocos / chemistry*
  • Cytokinins / chemistry*
  • Cytokinins / isolation & purification
  • Cytokinins / pharmacology
  • Magnetic Resonance Spectroscopy
  • Molecular Sequence Data
  • Molecular Structure
  • Oligosaccharides / chemistry*
  • Oligosaccharides / isolation & purification
  • Plants, Toxic
  • Spectrometry, Mass, Fast Atom Bombardment
  • Tobacco / drug effects
  • Tobacco / physiology


  • Cytokinins
  • Oligosaccharides