Identification and quantification of octanoyl glucuronide in the urine of children who ingested medium-chain triglycerides.
In addition to the previously described metabolites, octanoyl glucuronide was identified in the urine of four children who received medium-chain triglycerides. Octanoyl glucuronide in the urine of a child after ingestion of medium-chain triglycerides (C8:C10, 3:1) was quantitated as octanoic acid after glucuronidase treatment by means of gas chromatography/mass spectrometry. The urinary excretion increased rapidly to a maximum 1-2 h after ingestion, and decreased thereafter. During 0-3 h, 6.11 mumol of octanoyl glucuronide was excreted, which comprised 0.034% octanoic acid administered as glyceride, and 0.07% octanoic acid was postulated to be excreted as glucuronide within 24 h. Neither decanoyl glucuronide nor hexanoyl glucuronide was detected. Glucuronidation of branched medium-chain fatty acids, whose beta-oxidation is hindered, has been described previously. The present findings show that even straight-chain fatty acids undergo glucuronidation, although to a lesser extent, in addition to omega-oxidation and beta-oxidation.
D002210:Caprylates / Q000652:urine*; D002648:Child; D002849:Chromatography, Gas; D005965:Glucuronates / Q000652:urine; D006801:Humans; D008970:Molecular Weight; D014280:Triglycerides / Q000008:administration & dosage / Q000378:metabolism*
D002210:Caprylates; D005965:Glucuronates; D014280:Triglycerides; C047456:octanoylglucuronide