The capacity of four cholesterol oxidases from Nocardia erythropolis (
Ne), Streptomyces species(Ss), Brevibacterium species (Bs) and Pseudom
onas fluorescens (Pf) to degrade cholesterol in egg yolk at 4, 25 and
37 degrees C has been determined. The effects of enzyme/substrate conc
entration and incubation temperature on the enzymatic activity of thes
e cholesterol oxidases have also been investigated. The cholesterol de
grading capacity of these enzymes follows the sequence Pf>Ne>Ss>Bs. Up
to 93.4% cholesterol was degraded by cholesterol oxidases from P. flu
orescens and Streptomyces species after 72 h of incubation at 37 degre
es C. At 4 degrees C, P. fluorescens cholesterol oxidase could degrade
up to 64.9% cholesterol after 48 h.