Cultural conditions optimization for production of β-galactosidase from Bacillus licheniformis ATCC 12759 under solid-state fermentation

Abstract

Objective: The aim of this work was to study the optimal cultivation conditions for β-galactosidase production by Bacillus licheniformis ATCC 12759. Materials and methods: The screening of β-galactosidase production from B. licheniformis ATCC 12759 was performed by solid state fermentation method on media rich with rice bran (RB). Different factors were tested for the optimization of β-galactosidase production. Results: Certain fermentation parameters involving incubation time, incubation temperature, inoculum level, moisture content, initial pH, agitation speed, size of fermentation medium and optimum temperature of β-galactosidase activity were studied separately. Maximal amount of β-galactosidase production was obtained when solid-state fermentation (SSF) was carried out using RB, having inoculum level 35%, moisture content of 20%, initial pH 7.5 at 37°C for 48 h. Conclusion: Results indicated that optimal fermentation conditions play a key role in the maximum production of β-galactosidase from B. licheniformis ATCC 12759. This study shows the potential of the studied enzymes to be promoting candidates for the degradation of lactose and production of important bioproducts.