Production of β‐galactosidase by Trichoderma sp. through solid‐state fermentation targeting the recovery of galactooligosaccharides from whey cheese

Abstract

Optimization of β-galactosidase production by Trichoderma sp. under solid-state fermentation using wheat bran as solid substrate through an experimental design and its application targeting the recovery of galactooligosaccharides (GOS) from whey cheese. The β-galactosidase production by Trichoderma sp. increased 2·3-fold (2·67Ug-1 of substrate) culturing the fungus at 30°C for 187h, at an inoculum of 105 spores per ml, and a 1:1·65 (w/v) ratio of wheat bran to tap water. The best enzyme activity was obtained at 55°C and pH 4·5. The catalytic activity was maintained for up to 180min incubating at 35-45°C, and above 50% at acidic or alkaline pH for up to 24h. It also presented resistance to chemical compounds. β-galactosidase catalysed the hydrolysis of the lactose and the transgalactosylation reaction leading to the production of GOS. Trichoderma sp. produced β-galactosidase with transgalactosylation activity that may be used to recover GOS, products with high added value, from whey cheese. β-galactosidases are used in different industrial sectors. Therefore, the Trichoderma β-galactosidase is a promising alternative for the production of GOS as prebiotic from the dairy effluents, contributing to the reduction in the environmental impact.