STUDY ON DOMESTICATION OF A NITRILE HYDRATASE PRODUCING STRAIN AND OPTIMIZATION ON ITS NITRILE HYDRATASE PRODUCING CONDITIONS

A bacterial strain having higher nitrile hydratase activity and acrylonitrile concent rationed tolerance,numbered Nocardia sp LNSY06,is developed by repeated subculturing of it in the broth containing acrylonitrile with slightly increased.The specific nitrile hydratase activity of it increased up to 62.5 unit U/mg of dry cells,16 times higher than that of Nocardia sp LNSY06.The results show that the factors influencing nitrle hydratase activity mostly are glucose,urea,acrylon,acrylamide,Co~(2+),pH and temperature etc;The optimum conditions of the best extraction ratio are as follows: glucose 20g/L,urea 0.06g/L,acrylon 4%,acrylamide 20%,Co~(2+) 0.3g/L,pH 7.0 and temperature 28℃.