Effect of by-products from the dairy industry as alternative inducers of recombinant β-galactosidase expression.

Objective: The aim of the present study was to evaluate the efficiency of lactose derived from cheese whey and cheese whey permeate as inducer of recombinant Kluyveromyces sp. β-galactosidase enzyme produced in Escherichia coli. Two E.

Chelation by collagen in the immobilization of Aspergillus oryzae β-galactosidase: A potential biocatalyst to hydrolyze lactose by batch processes.

This work is the first study of the immobilization of Aspergillus oryzae β-galactosidase (Gal) on powdered collagen (Col) that had formed a chelate with aluminum (Col-Al-Gal). Other collagen treatments, including those with acetic acid, glutaraldehyde, and a combination of aluminum and glutaraldehyde (Col-Al-Glu-Gal), were also tested. High-yield (superior to 80%) and high-efficiency (superior to 99%) immobilization was obtained for the derivatives Col-Al-Gal and Col-Al-Glu-Gal, even at high protein loads (500-1,000 mg g of support).