AS-2 thus obtained homogeneous as shown by Sepharose CL-4B column chromatography and cellulose acetate film electrophoresis.

• AS-2经Sepharose CL-4B柱层析为单一对称峰,经醋酸纤维素膜电泳为一条带,冻融后高速离心无沉淀可证明其为均一级分。