Identification of a major cytokinin in coconut milk.
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.
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D003059:Cocos / Q000737:chemistry*; D003583:Cytokinins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009844:Oligosaccharides / Q000737:chemistry* / Q000302:isolation & purification; D010947:Plants, Toxic; D016339:Spectrometry, Mass, Fast Atom Bombardment; D014026:Nicotiana / Q000187:drug effects / Q000502:physiology
D003583:Cytokinins; D009844:Oligosaccharides