Abstract: This study investigated the stability of carnosic acid(CA) in simulated body fluid using HPLC and preparative HPLC.The body fluid,including simulated gastric juice,simulated intestinal juice,blank simulated gastric juice and blank simulated intestinal juice,was prepared according to “Chinese Pharmacopoeia”.It was revealed that no significant changes of carnosic acid content was observed in simulated gastric juice and blank simulate juice,while several degradation products,such as rosmanol,epirosmanol,and carnosol,were detected in simulated intestinal juice and blank simulated intestinal juice.Specifically,the pH value exerted a significant impact on the stability of CA in body fluid,which guided further development of CA.

Key words: carnosic acid, simulated body fluid, stability, degradation products