Recovery of -galactosidase produced by Kluyveromyces lactis by ion-exchange chromatography: Influence of pH and ionic strength parameters

The use of beta-galactosidase in food products has been a major focus of the industry. Therefore, the development of efficient and inexpensive methodologies to purify it is essential. Thus, this study aimed to recover the enzyme beta-galactosidase (beta-gal) by ion-exchange chromatography in a fixed-bed column. Batch adsorption tests were performed using four types of adsorbents. The beta-gal adsorption capacity in batch mode using Streamline DEAE resin presented the best performance, with a retention capacity of 18.77 +/- 0.14 U/g at pH 6.0. A 2(2) experimental design was applied to optimize the beta-gal recovery using an AKTA Start system, evaluating the ionic strength and the pH as process parameters. The results showed that ionic strength exerted a greater influence on fold purification (FP). The beta-gal fraction in elution using 0.1-0.4 M of NaCl showed a yield of 51.65 +/- 0.17% and FP of 2.00 +/- 0.43. Electrophoresis confirmed the beta-gal recovery, where an evident band with a molecular weight between 60 and 120 kDa was observed. These results point to the recovery of a stable beta-gal of K. lactis with potential industrial applications.