An extracellular neutral endo-beta-mannanase(endo-beta-1, 4-D-mannan mannanohydrolase, EC 3.2.1.78)of Bacillus subtilis BM9602 was purified to electrophoretic homogeneity by ammonium sulfate precipitation and DEAE-cellulose DE22 chromatography with 45.5 fold and 5.9% yield. It's molecular weight and