Metabolite profile analysis and pharmacokinetic study of emodin,baicalin and geniposide in rats

1.Emodin, baicalin and geniposide are the major bioactive components in Da-Huang, Huang-Qin and Zhi-Zi which are herbal medicines widely used in Asian nations.

2.The metabolism of the three compounds was found to undergo hydroxylation, decarboxylation, dehydration, methylation, hydrolysis, hydrogenation, dihydrogenation, sulfation, glucosidation and/or glucuronidation. A total of 63 metabolites were detected in urine, plasma and bile of rats given a mixture of the three compounds.

3.Pharmacokinetic properties of the three compounds were determined in rats given the extracts of Da-Huang, Huang-Qin and Zhi-Zi. The pharmacokinetic parameters for emodin, baicalin and geniposide were found to be 0.13?±?0.11, 0.25?±?0.12 and 0.40?±?0.09?h (T_max); 21?±?9, 1515?±?254 and 482?±?50?ng/mL (C_max); 8.6?±?5.5, 18.3?±?2.8 and 22.1?±?17.2?h (t_1/2); 29?±?20, 16886?±?3734 and 2936?±?551?ng/mL?h (AUC_(0–t)); and 37?±?20, 22624?±?6295 and 3582?±?820?ng/mL?h (AUC_(0–∞)).

4.The metabolism and pharmacokinetic studies facilitate appropriate employment of Da-Huang, Huang-Qin and Zhi-Zi in clinic.