Abstract：Experimental design was employed to study the effects of several factors on the production of nuclease P1 by Penicillium citrinum M02, such as carbon source, nitrogen source, phosphor source and corn steep liquor which acted as complementary nitrogen source. The results of two experiments showed that corn steep liquor could remarkably promote the production of nuclease P1. In addition, one model that can describe the fermentation perfectly was gained from these experiments. When nuclease P1 was produced on the optimized medium calculated from this model, its yield was 648.3 U/ml that is comparable with 661 U/ml from the model. And it is improved by 70% compared with the 380 U/ml, which was gained on the original medium at the same time. The possible reason for corn steep liquor promoting nuclease P1 fermentation is that corn steep liquor contains more useful amino acids such as glycin, alanine, serine and so on.
2003, Vol. 3 
