Production of Thermostable Beta-Galactosidase from Thermophilic Fungi

Many people suffer from lactose intolerance because of lack of the required enzyme, lactase (beta-galactosidase) in their digestive system. Lactose intolerance is common as much as 70-90% of most populations. Some commercial solutions have been found against lactose intolerance such as low lactose milk and oral enzyme tablets. Fungal -galactosidases are generally used for the production of oral enzyme tablets due to their high stability at stomach acidity. While, yeast -galactosidases obtained from K. lactis, K. fragilis are used for low-lactose milk production due to their activity at neutral pH (pH of milk). Lactase is also used in food industry for other purposes like improving functional properties of dairy products, oligosaccharide formation to be used in functional foods and hydrolysis of lactose in whey...etc. Previous studies indicate that enzymes of thermophilic fungi generally show their activity at or above neutral pH in contrast to what is observed in other fungi. In this respect, this research illustrates the production and partial purification of -galactosidase from a thermophilic fungus, determination of conditions for better activity and production.

Autorentext

Meltem SOYDAN KARABACAK, MSc on Food Engineering at Middle East Technical University (METU), Scientific Prog. Ass. Expert in The Scientific and Technological Research Council of Turkey (2006-), Ankara. Zumrut Begum OGEL, PhD on Biotechnology at Leeds University,UK, Professor at Food Engineering and Biotechnology Departments at METU, Ankara, Turkey.