Ovine metabolism of saponins: evaluation of a method for estimating the ovine uptake of steroidal saponins from Narthecium ossifragum.
A sheep was dosed three times per day over six consecutive days with 70 g Narthecium ossifragum, and once on the seventh day with 70 g N. ossifragum. Additionally, it was dosed once on days 1-7 with 20 mg of [20,23,23-2H3]sarsasapogenin. After 7 days, the sheep was killed and GC-MS analysis of the free and conjugated sapogenin content in bile, urine, rumen, duodenum, jejunum, colon and rectum samples collected from the sheep, faecal samples collected on days 4-7, and dosed plant material was performed. The N. ossifragum contained mainly sarsasapogenin and smilagenin. Only neglible levels of deuterium-labelled sarsasapogenins were detected in the samples from the animal. Ingested saponins were quickly hydrolysed in the rumen to free sapogenins and, in part, epimerized at C-3 to afford episapogenins. The absorption of free sapogenins appeared to occur in the jejunum. The concentration of sapogenins in faeces reached a plateau 108 h after dosing started.
Flåøyen
A
A
National Veterinary Institute, Oslo, Norway.
Wilkins
A L
AL
Deng
D
D
Brekke
T
T
D000818:Animals; D005243:Feces / Q000737:chemistry; D005260:Female; D007408:Intestinal Absorption; D007583:Jejunum / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D010936:Plant Extracts / Q000378:metabolism / Q000493:pharmacokinetics / Q000633:toxicity; D010947:Plants, Toxic / Q000378:metabolism*; D012503:Saponins / Q000378:metabolism / Q000493:pharmacokinetics / Q000633:toxicity; D012756:Sheep / Q000378:metabolism*; D013150:Spirostans / Q000378:metabolism* / Q000493:pharmacokinetics / Q000633:toxicity
D010936:Plant Extracts; D012503:Saponins; D013150:Spirostans; C046297:sarsasapogenin