OPTIMIZATION OF ISOLATION AND PURIFICATION OF THE BACTERIOCIN FROM ENTEROCOCCUS ITALICUS ONU 547 BY ANION-EXCHANGE CHROMATOGRAPHY

Aim. The aim of the work was to optimize isolation and purification of the bacteriocin from E. italicus ONU 547, which has biotechnological potential by low pressure anion exchange chromatography. Methods. Anion exchange chromatography by the BioLogic LP system with the cartridge Bio-Scale Mini Macro-Prep High Q was used for isolation of the bacteriocin from the culture liquid and for its partial purification. Two-step and three-step elution protocols were tested in order to increase yield of the bacteriocin and its purity. Results. The bacteriocin from culture liquid of E. italicus ONU 547 (320 AU/mL) was isolated and partially purified by anion-exchange chromatography with low-pressure system. The slightly alkaline hydrogen potential (pH = 8.0) of culture liquid and mobile phase was suitable for effective binding of the bacteriocin to the column with a positive charged matrix. The two-step (10% and 100% Buffer B with 1 M NaCl) elution procedure resulted in 4.4% yield of the bacteriocin, while three-step elution (10%, 50% and 100%) – 5%. The simplified procedure for bacteriocin isolation and purification is proposed. Conclusions. Low pressure anion-exchange chromatography with pH 8.0 of the mobile phase is effective for isolation of the bacteriocin directly from culture liquid of E. italicus ONU 547 and for its partial purification. Three-step elution procedure with 10%, 50% and 100% 1M NaCl leads to higher purity and yield of the bacteriocin.