OBJECTIVETo establish the best hydrolytic conditions from phorbol esters.

METHODThe orthogonal experiment was used to optimize 4 factors, which were reaction time, ratio of solid-to-liquid, hydrolytic times, and temperature. Diamonsil C18 column (4. 6 mm x 250 mm, 5 microm) was used and the mobile phase was consisted of acetonitrile and water for HPLC detection. The detection wavelength was set at 234 nm, the flow rate was 1 mL x min(-1), and the column temperature was 25 degrees C.

RESULTThe optimum conditions were 10 h of reaction time, 1:6 of solid-to-liquid (BaOH/MeOH) ratio, 25 degrees C of temperature, and one time of hydrolysis. There was a good linear relationship of phorbol in the range of 4.28-107 mg x L(-1) (r = 0.999 9), and the average recovery was 97.89%, with RSD 0.78%.

CONCLUSIONThe method is steady, reliable and reproducible, and it provides a mean for future study.