Hepatic Biotransformation Profiles of Sulphamonomethoxine in Food-Producing Animals and Rats in Vitro

Abstract

Hydroxylation and acetylation of sulphamonomethoxine (SMM) and deacetylation of N4-acetyl SMM (N4-AcSMM) were estimated in liver post-mitochondrial supernatants (S-9) from laying hens, female cattle, swine and rats. The formation of hydroxylated SMM, 2,6-dihydroxy SMM (2,6-diOH-SMM), was found only with hen S-9s. N4-acetylation rate of SMM was the highest in pig S-9s, followed by rat, then hen or cow S-9s. All S-9s from the four species deacetylated N4-AcSMM. In hen S-9s, the rate of 2,6-dihydroxylation was higher during incubation at 41 °C than at 37 °C.

Characterization and estimation of sulfaquinoxaline metabolites in animal tissues using liquid chromatography coupled to tandem mass spectrometry

“…18 Moreover, acetylated metabolites of sulfonamides have no bacterial activity, a lower solubility in physiological pH, which may lead to kidney precipitation, de-acetylation of the parent drug both in vivo and in vitro and higher plasma protein binding than the parent drug. [19][20][21][22][23][24] Considering the differences found among animal species in sulfonamide metabolization, especially for liver mediated biotransformation, further knowledge of these processes can be considered relevant not only for pharmacological studies, but also for the analysis of sulfonamide residues in food. 25 Like other sulfonamides, SQX has a maximum residue limit (MRL) established for several food matrices.…”