<b>Use of agroindustrial residues in biotechnological process by beta-galactosidase production from <em>Kluyveromyces marxianus</em> CCT 7082</b> - doi: 10.4025/actascitechnol.v33i2.9919

Abstract

The objective of this work was to evaluate the composition of the culture medium for the production of the enzyme β-galactosidase from Kluyveromyces marxianus CCT 7082 using an experimental design. Enzyme production was carried out in a medium consisting of cheese whey, corn steep liquor (CSL) and Prodex-lac^® yeast hydrolyzate. A factorial fractional design (25-1) was performed to determine the significant variables in the production of the enzyme. Different concentrations of lactose present in whey (10-70 g L^-1), CSL (10-100 g L^-1), Prodex-lac (40-20 g L^-1), (NH4)2SO4 (0-10 g L^-1) and pH (5-7) were tested. Lactose concentration, CSL and pH were the variables that showed a statistically significant effect on enzyme activity within the ranges studied, and these variables were used in a central composite rotatable design to optimize production of the enzyme. The ranges used were: lactose concentration 40-100 g L^-1, CSL 10-120 g L^-1, and pH 3.5-6.5. The conditions that resulted in higher enzyme activity (1400 U g ^-1) were 70 g L^-1 lactose, 65 g L^-1 CSL, 4 g L^-1 Prodex-lac and pH 5, yielding 61 U L^-1 h^-1