Table 1.

Purification of extracellular endoxylanase expressed by E. coli

Step	Volume (mL)	Protein (mg/mL)	Activity (U/mL)	Spec. activity (U/mg protein)	Yield (%)	Purification (fold)
Crude extract	400	0.90	450	500	100	1
Nickel column	95	0.16	1400	8750	74	17.5