Enzymatic detoxification using lipophilic hollow-fiber membranes: II. Sulfation reactions

A lipophilic hollow-fiber technique was used in the enzymatic sulfation of lipophilic toxins. Endogenous and exogenous toxins, for which glucuronidation reactions already were demonstrated with this technique, were submitted to sulfate transferase reaction as an alternative phase-II detoxification route. Native enzyme was circulated on the external side of a lipophilic hollow-fiber membrane while the toxin-containing media (serum or aqueous solution) were circulated inside the hollow fiber. Sulfation reactions were catalyzed by rabbit liver cytosol, with a specific sulfate transferase activity of 626 nmol/min-mg protein. Clearance of the hollow-fiber module for phenol, p-cresol, paracetamol, 2-aminophenol, and 5-hydroxyindol were determined to be 38.1, 47.2, 2.7, 5.3, and 3.2 pmol/mg protein/h/cm2 hollow-fiber surface, respectively. This technique allows sulfation reactions with crude enzyme preparations over long periods without loss of activity from covalent immobilization and without immunological hazards.