PHARMACOKINETICS AND DISPOSITION OF β-ELEMENE IN RATS

AIM　To study the pharmacokinetics, absorption, distrbution and excretion of β-elemene obtained from the roots and stems of Curcuma wenynjin Y.H Chen et C.Ling. in rats. METHODS　A GC method for isolation and determination of β-elemene in biological specimens was used. RESULTS　After a single iv dose to rats, the plasma concentration-time course of β-elemene fitted well to a two-compartment open model. With regard to ip administration of a single dose of 100 mg.kg^-1 to rats, the absorption of the drug was rapid. Elimination of the drug from plasma was found to be in accord with linear kinetics, whereas the elimination half-lives were longer than that of iv administration. Only small amount of unchanged β-elemene was excreted in urine, feces and bile after iv and ip administration. Plasma protein binding ratio was obtained from two different levels of β-elemene, 97.7% from 60 μg.mL^-1 and 96.5% from 100 μg.mL^-1. CONCLUSION　β-elemene was eliminated at a rapid rate and distributed widely in the body. The protein binding was found to be high. Unchanged β-elemene excreted via urine, feces and bile were very few.