Partitioning of beta-glucosidase from Trichoderma reesei in poly(ethylene glycol) and potassium phosphate aqueous two-phase systems:Influence of pH and temperature

摘要

This study evaluates the influence of pH and temperature on the partition coefficient of beta-glucosidase and total protein in order to determine the best conditions for the purification of the enzyme in poly(ethylene glycol) (PEG) 4000 (8%,w/w) and potassium phosphate salt (13%,w/w) aqueous two-phase systems.The partition coefficient increased with pH and temperature for the ranges investigated (i.e.,pH:6.0-7.5;temperature:25-55 deg C).Yield and selectivity were key criteria for the selection of the optimum separation condition for enzyme purification.The highest selectivity was achieved at a pH of 6.5 and a temperature of 25 deg C.A beta-glucosidase yield greater than 92% was obtained in the bottom phase for pH values less than 7.0 and temperatures below 35 deg C.