AbstractBACKGROUNDPolyamines are essentially involved in cell division and differentiation. Transport of polyamines is adenosine triphosphate (ATP)‐dependent, while phytic acid is the major reserve of phosphate essential to the energy‐producing machinery of cells. Thus polyamines might enhance phytic acid degradation during mung bean germination. In this study, different polyamines (putrescine (Put), spermidine (Spd) and spermine (Spm)) and dicyclohexylamine (DCHA, an inhibitor of Spd synthesis) were applied to investigate the function of polyamines on phytic acid degradation.RESULTSSpd exhibited the best effect at the same concentration. Simultaneously, exogenous Spd improved sprout growth and enhanced the accumulation of gibberellin acid 3 (GA3), indole‐3‐acetic acid (IAA), abscisic acid (ABA) and cytokinin (CTK). This must be due to the increased endogenous polyamine contents. Apart from dramatically reducing phytic acid content, Spd resulted in the up‐regulation of PA, PAP, MIPP and ALP transcript levels and the enhancement of phytase and acid phosphatase activities. However, DCHA application caused the opposite results, because it decreased endogenous polyamine contents. Furthermore, Spd alleviated the DCHA‐induced inhibitory effect to some extent.CONCLUSIONOverall, polyamines, especially Spd, could accelerate phytic acid degradation in mung bean sprouts by inducing the synthesis of endogenous polyamines and phytohormones and enhancing the growth of sprouts. © 2017 Society of Chemical Industry