Synthesis and Antioxidative Activity of Piperine Derivatives Containing Phenolic Hydroxyl

Figure 2

DPPH and ABTS free radical clearance curves of piperine and its derivatives. (a) The DPPH free radical clearance rate (IP) of piperine and its derivatives at different concentrations. (b) The ABTS free radical clearance rate (IP) of piperine and its derivatives at different concentrations.

(a)

(b)