Avaliar métodos de extração da β-galactosidase produzida por Kluyveromyces marxianus a partir do permeado de soro de leite

Abstract

Whey permeate is a byproduct of the BOD and COD high-load dairy industry. It is obtained by concentrating cheese whey, its composition is basically water and lactose, which makes it an interesting medium for microorganisms capable of ferment this molecule, such as Kluyveromyces marxianus which converts lactose to galactose and glucose due to the enzymatic activity of β-galactosidase. This yeast produces the enzyme intracellularly, so extraction methods are required to obtain the enzyme. The aim of the study was to extract β-galactosidase, produced by k. marxianus in whey permeate by different cell disruption methods. The methods performed were abrasion with glass beads, ultrasonic rupture, thermal shock, and chemical agents such as SDS and Triton X-100. The results showed that the methods used achieved good yields, being the thermal shock the one with best result, a yield of 203%, with enzymatic activity values of 19.1 UONPG /gcel.