Bound sulphadimidine residues in raw fermented sausage: release under acidic conditions and bioavailability in rats

 Sulphadimidine (SDM), a drug frequently administered to pigs, is partially converted into other compounds by processing meat to produce raw, fermented sausage. With the aid of ¹⁴C-labelled SDM, evidence was obtained that part of the radioactive matter was covalently bound to the matrix. Part of these bound residues could be released in vitro by 4 M HCl at 21  °C or by 0.024 M HCl at 37  °C. Female rats were also able to release bound SDM residues and to excrete these in their urine, in amounts approaching those obtained by treatment with 4 M HCl. Both the parent compound and its main metabolite, N ⁴-acetyl-SDM, were observed in the urine of rats. Received: 29 December 1997 / Revised version: 20 February 1998