Larissa Nayhara Soares Santana Falleiros

Sucrose hydrolysis by invertase immobilized on Duolite A-568 employing a packed-bed reactor

ABSTRACT The conversion of sucrose to a highly concentrated commercial syrup by immobilized invertase by combining the processes of adsorption and cross-linking using Duolite A-568 as the carrier was studied. Central Composite Design (CCD) was used to assess the effect of glutaraldehyde concentration and cross-linking reaction time on immobilized enzyme activity throughout the hydrolysis of sucrose in a batch reactor. Cross-linking optimization allowed us to find the optimum conditions for activity with a glutaraldehyde concentration of 0.6 g · L−1 and a cross-linking time of 6 h. The temperature and pH that maximized the activity of the immobilized biocatalyst in the cross-linking process were 50°C and 4.0, respectively. Cross-linking allows the biocatalyst to be active at higher temperatures and lower pH. High-sucrose conversions to invert sugar using a continuous fixed-bed reactor were obtained. The immobilized biocatalyst also demonstrated greater thermal stability at low temperatures.