Study of the Conditions for a Nitrile Hydratase Producing Strain to Produce Enzyme Efficiently

A bacterial strain of Nocardia sp which was filtered from waste water of Fushun Acrylonitrile Factory having nitrile hydratase activity and acrylonitrile tolerance was developed by repeated subculturing in the broth containing acrylonitrile with successively slightly increased acrylonitrile concentration.Enzyme activity of the domesticated strain was 15 times higher than that of original Nocardia sp.The optimum conditions of cultivation were glucose 25 g/L,urea 0.06 g/L,acrylonitrile5%,acrylamide20%,Co~(2+) 0.02 g/L,pH=7.0 and temperature 22 ℃.An orthogonal experiment of L_9(3~4)was devised,which can make certain that temperature and urea are the prominent factors.