STABILITY AND ACTIVITY OF IMMOBILIZED HYDROLYTIC ENZYMES IN 2-LIQUID-PHASE SYSTEMS - ACID-PHOSPHATASE, BETA-GLUCOSIDASE, AND BETA-FRUCTOFURANOSIDASE ENTRAPPED IN POLY(2-HYDROXYETHYL METHACRYLATE) MATRICES

Enzyme storage stability and hydrolysis yield were measured in experim ents carried out with three model hydrolytic enzymes:acid phosphatase (EC3.1.3.2), beta-glucosidase (EC3.2.1.4), and beta-fructofuranosidase (EC 3.2.1.26) entrapped in hydrogels of poly(2-hydroxyethyl methacryl ate). Runs were performed at 30-degrees-C, under intensive stirring (5 00 rev min-1), in 50% v/v biphasic media prepared with buffer and orga nic solvents, whose log P value varied from 0.68 to 8.8. Storage stabi lity was also monitored in the pure solvents. The small average partic le size (125-210 mum) and the intensive stirring eliminate hindrances of intra- and interphase mass transfer resistances. The hydrophilic ma trix protects the enzymes against thermal and chemical deactivation, t hus allowing good production per unit weight of biocatalyst. In biphas ic media, storage stability, with the exception of acid phosphatase, w as not dependent on solvent polarity. On the contrary, a significant t rend was observed when the enzymes were stored in neat organic solvent s.