EFFECTS OF THE GARLIC COMPONENTS DIALLYL SULFIDE AND DIALLYL DISULFIDE ON ARYLAMINE N-ACETYLTRANSFERASE ACTIVITY IN HUMAN COLON-TUMOR CELLS

Diallyl sulfide (DAS) and diallyl disulfide (DADS). major components o f garlic, were used to determine inhibition of arylamine N-acetyltrans ferase (NAT) activity in a human colon tumour (adenocarcinoma) cell li ne. Two assay Systems were performed, one with cellular cytosols (9000 g supernatant), the other with intact bacterial cell suspensions. The NAT activity in a human colon tumour cell line was inhibited by DAS a nd DADS in a dose-dependent manner in both system: that is, the greate r the concentration of DAS and DADS in the reaction, the greater the i nhibition of NAT activities in both systems. The data also indicated t hat DAS and DADS decrease the apparent values of K-m and V-max of NAT enzymes from human colon tumour cells in both systems examined. This i s the first report to demonstrate that garlic components do affect hum an colon tumour cell NAT activity. (C) 1998 Elsevier Science Ltd. All rights reserved.