Open AccessCharacterization of free and immobilized invertase regarding activity and energy of activation
Author(s) -
Rosângela Bergamasco,
Fátima de Jesus Bassetti,
Flávio Faria de Moraes,
Gisella Maria Zanin
Publication year - 2000
Publication title -
brazilian journal of chemical engineering/brazilian journal of chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.313
H-Index - 52
eISSN - 1678-4383
pISSN - 0104-6632
DOI - 10.1590/s0104-66322000000400051
Subject(s) - invertase , glutaraldehyde , chemistry , immobilized enzyme , sucrose , activation energy , yield (engineering) , nuclear chemistry , enzyme , silane , covalent bond , hydrolysis , chromatography , biochemistry , organic chemistry , materials science , metallurgy
Invertase from NOVO Nordisk has been immobilized in controlled pore silica particles (diameter: 0.351 mm and mean pore size: 37.5 nm) by covalent binding with the silane-glutaraldehyde method. The activity of the free and immobilized enzyme (IE) was determined with 5% (w/v) sucrose, at 35 to 65ºC and pH from 3 to 7. Maximum activities were found in the pH range from 5 to 6 for free invertase, and pH 4.5 for the IE. Activity yield for the IE was 24%. The Energy of Activation (Ea) was found to be a function of pH, giving for free invertase, Ea = 7.0 and 6.86 kcal/mol at pH 5.0 and 5.5, respectively, whereas for the immobilized enzyme, Ea = 6.55 and 5.93 kcal/mol at pH 4.5 and 5.0, respectively