Pharmacokinetic and Bioavailability Studies of Embelin after Intravenous and Oral Administration to Rats

Embelin exhibits the broad bioactivities such as antitumor, antifertility, antidiabetic, anti-inflammatory, antioxidant, anticonvulsant, anxiolytic, antimicrobial, and hepatoprotective activity. In order to further understand the pharmacokinetic characteristics and oral bioavailability of embelin in vivo, the concentration of embelin in rat plasma was determined by a sensitive high-performance liquid chromatography with diode array detector (HPLC-DAD). The preparation of samples was accomplished by a simple precipitating protein with methanol. Emodin was selected as the internal standard (IS). Embelin and IS were completely separated on an analytical column (Extend-C(18), 4.6 × 250 mm, 5 μm) using 0.1% phosphoric acid in methanol and 0.1% phosphoric acid in aqueous solution (90:10, v/v) as the mobile phase. The lower limit of quantification was 0.15 μg/mL. Oral bioavailability of embelin was 30.2 ± 11.9%. This study could provide the information about pharmacokinetics and oral bioavailability of embelin, which was useful to assess the clinic efficacy and safety and promote further development of embelin.