CORTISOL DELTA-1-DEHYDROGENATION BY CELLS OF ARTHROBACTER-SIMPLEX IMMOBILIZED BY CAPTURE ON THE SURFACE OF UNWOVEN CLOTH COATED WITH A PYRIDINIUM-TYPE POLYMER

Cells of Arthrobacter simplex having 3-ketosteroid-DELTA-1-dehydromonogenase activity were immobilized by capture on the surface of unwoven cloth, which was coated with a copolymer of N-benzyl-4-vinylpyridinium chloride and styrene (soluble BVPS), a pyridinium-type polymer. The captured bacterial cells catalyzed the dehydrogenation of cortisol to prednisolone in solvents containing methanol. A fixed-bed column reactor 15 mm in diameter and 12 cm long was continuously operated. The reactor contained about 200 mg of A. simplex cells, captured on an unwoven cloth 12 cm wide, 20 cm long, and 0.5 mm thick coated with 6.5 g/m2 of the soluble BVPS, and yielded approximately 90% prednisolone during 6 d when the influent cortisol concentration was 1.0 mmol/l and the space velocity was 0.57 h-1 at 20-degrees-C and pH 8.2.