HPLC chromatograms indicated that transformation of gibberellic acid (
GA3) to the corresponding dicarboxylic acid via iso-GA3 occurred in we
ak alkaline solution. The bioactivity of this dicarboxylic acid was ab
out 20% that of GA3 and above 0.3 M NaOH this compound appeared to dec
ompose. Aqueous solutions of NaOH cannot, therefore, be used as solven
t in bioassays of GA3 activity.