Purification of lumbrokinase from Eisenia fetida using aqueous two-phase systems and anion-exchange chromatography

An 8.1% polyethyleneglycol (PEG) 300/22.2% phosphate aqueous two-phase system was used to obtain a clear extract of the earthworm Eisenia fetida. Lumbrokinase was then purified from the extract by anion-exchange chromatography at pH 4.6. 80% enzyme activity was recovered with a purification factor of 8.0 and 97% purity. No further purification was achieved by submitting the final product to chromatography on benzamidine-agarose.