EXTRACTION OF CYTOKININ NUCLEOTIDES WITH BIELESKI SOLVENTS - IS THE INCONVENIENCE WARRANTED

Two widely used cytokinin extraction techniques were compared when [8-C-14]benzyladenine was fed and subsequently extracted from five-week-old soybean callus. The effectiveness of a modified Bieleski's (1964) method was compared with a traditional 80 % ethanolic extraction. Phosphatases present in plant tissues convert [9R-MP]BA to [9R]BA. Thus high nucleoside ([9R]BA) levels relative to detectable monophosphate ([9R-MP]BA) could be indicative of high phosphorolytic activity during extraction of the tissue, particularly after homogenisation of the material. No substantial difference in the proportions of nucleoside and ribotide resulted from the two extraction methods. Both methods resulted in successful recovery of the nucleotide. This indicates that neither of the extraction techniques investigated have a lesser or greater effect on plant phosphatases. However, with the modified Bieleski method, more of the breakdown product Ade was detected in the extract.