Analysis of transformation and excretion of β-asarone in rabbits with GC-MS.

The objective of this work was to analyze transformation and excretion of β-asarone in rabbits with gas chromatography-mass spectrometry (GC-MS). The rabbits were administered IV at a dose of 30 mg/kg body weight β-asarone-water-propylene glycol (6:34:60, v/v/v), and urine and feces were collected within 6, 12 and 24 h. At 24 h, the animals were killed and bile was collected. Urine (2 mL) and bile (2 mL) samples were extracted with ether (4 mL), and the feces samples (2 g) were prepared by making an ether-feces (2:1, v/w) homogenate. Ether phase was evaporated and 25 µL psoralen-ether (2.95:1 w/v) was added. All samples were measured with GC-MS. β-Asarone was excreted in urine, feces and bile, and the excretion efficiency was about 62% in urine, 22% in feces, and 16% in bile. About 22% β-asarone was converted into α-asarone. Most β-asarone were excreted in 12 h. Gender differences accounted for no significant influence on the transformation and excretion of β-asarone.