Caffeic acid phenethyl ester exhibiting distinctive binding interaction with human serum albumin implies the pharmacokinetic basis of propolis bioactive components

•Probing a distinctive pharmacokinetic interaction between caffeic acid phenethyl ester (CAPE) and human serum albumin (HAS) in vitro.•Binding affinity of CAPE and HAS is much stronger than that of the other propolis components.•CAPE binds on HSA subdomain IIA through hydrogen bonds and van der Waals force.•Binding distance of CAPE and HAS (5.7nm) is longer than that of the other propolis components.