Optimization of pancreatic trypsin extraction in peg/citrate aqueous two-phase systems

PEREZ, ROCIO LAURA; LOUREIRO, DANA B.; NERLI, BIBIANA; TUBIO, GISELA

PROTEIN EXPRESSION AND PURIFICATION

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2015 vol. 106 p. 66 - 71

1046-5928

Enzyme extraction using aqueous two-phase systems (ATPS) has been increasingly used as a primary recovery technique which integrates the clarification, concentration and partial purification of important biomolecules from their natural source in a single step. The goal of this work was to optimize the extraction of trypsin from pancreas homogenate with polyethylene glycol and sodium citrate (PEG/NaCit) ATPS by using the tools of experimental design. The variables NaCl concentration, added inert salt, the top/bottom phase volume ratio, Vr, and the biomass loaded into the system ?in percentage? were selected as the main factors in the trypsin extraction. The yield (%) and the purification factor of trypsin were considered the responses to be optimized. The Central Composite Design and the Response Surface Analysis proved to be suitable tools for a quick and efficient study. As a result, the optimal extraction conditions in PEG3350/NaCit system were 3.34% wt/wt for NaCl concentration, a biomass load which represented 9.30% wt/wt of the total ATPS mass and 6.37 top/bottom volume ratio giving a purification factor of 2.55 and a yield of 99.7 % in top phase.