Changes in phenolic acid composition and associated enzyme activity in shoot and kernel fractions of brown rice during germination

•PAL activity increased during germination for 2 days, but decreased thereafter.•Insoluble phenolic acid contents and CW-PRX activity increased during germination.•PAL and CW-PRX play important roles in changing the composition of phenolic acids.•Antioxidant activity of GBR continually increased during germination.