Miles, Christopher O.Wilkins, A.L.Erasmus, G.L.Kellerman, T. StephanusVerwoerd, Daniel Wynand2013-12-092013-12-0920131994Miles, CO, Wilkins, AL, Erasmus, GL, Kellerman, TS & Coetzer, JAW 1994, 'Photosensitivity in South Africa. VII. Chemical composition of biliary crystals from a sheep with experimentally induced geeldikkop’, Onderstepoort Journal of Veterinary Research, vol. 61, no. 3, pp. 215-222.0330-2465http://hdl.handle.net/2263/32747The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Geeldikkop was induced in a sheep by oral administration of crude saponins from Tribulus terrestris. Centrifugation of the bile from this sheep gave a pale green sediment of crystalloid material which was insoluble in common organic solvents, but soluble in acetic acid. Analysis of the crystalloid material by ¹H and ¹³C NMR, EDXA, TLC, LSIMS, and by acidic hydrolysis followed by TLC and GC-MS, revealed it to be composed principally of a 6:1 mixture of the calcium salts of the β-D-glucuronides of the steroidal sapogenins epismilagenin and episarsasapogenin. The administered saponin was found to contain glycosides of the steroidal sapogenins diosgenin, yamogenin, epismilagenin, tigogenin, neotigogenin, gitogenin and neogitogenin in the ratio 10:7:1:11:7:35:25. A metabolic pathway for the conversion of diosgenin and yamogenin saponins to the biliary glucuronides is proposed.en© ARC-Onderstepoort (original). © University of Pretoria. Dept of Library Services (digital).Veterinary medicineSheepPlant poisoningVeterinary medicine -- South AfricaPoisonous snakes -- VenomArticle