It is the optimal time for subjecting creatine to the medium when cultured to 12h and the concentration of creatine was 0 . 75 % . creatine , sarcosine and choline chloride could induce the creatinase production and creatine was the optimal inducer , but creatinine and urea could not induce the creatinase production . 3 purification of creatinase the process of creatinase purification was performed as follows : first the enzyme was completely precipitated in the range of 40 - 80 % of saturation with ammonia sulfate fraction precipitation 最佳氮源为玉米浆和蛋白胨，最佳比例为2 ： 3 ，最佳浓度为1 . 6 ；加入其它碳源时有助于菌株稳定产酶； 100ml摇瓶的最佳装液量为15ml ；肌酸、肌氨酸和氯化胆碱都能诱导菌株产酶，其中肌酸诱导产酶的效果最好，而肌酐和尿素不能诱导菌株产酶；诱导物肌酸的最适加入时间为接种培养12小时后，最适加入量为0 . 75 。
