ABSTRACT
Galactooligosaccharides (GOS) occur naturally in trace amounts in human milk. Bifidobacterial intestinal microbiota appears to be established by the use of human milk oligosaccharides. ß-Galactosidase naturally occurs in a wide variety of organisms including microorganisms, plants, and animals. Microbial sources of ß-galactosidases are of great technological interest due to various advantages such as easy handling, high multiplication rate, and good production yield. Microbial ß-galactosidases for GOS production include native crude or purified enzymes, recombinant enzymes, immobilized enzymes, and whole-cell biotransformations. Reactions can start from lactose or lactose-containing products such as milk and whey. The maximal GOS yield can be influenced by reaction conditions such as lactose concentration, temperature, pH, and the reaction time. The initial lactose concentration is considered to be one of the key factors affecting the maximal GOS concentration achieved. Enzyme immobilization has always received a great deal of attention for use in industrial-scale processes.
