Hepatic biotransformation profiles of sulphamonomethoxine in food-producing animals and rats in vitro

Hydroxylation and acetylation of sulphamonomethoxine (SMM) and deacetylation of N-4-acetyl SMM (N-4-AcSMM) were estimated in liver postmitochondrial 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. N-4-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 degrees C than at 37 degrees C.