Depression of lactose hydrolysis by yeasts.

To investigate the role that the known disaccharidase depression may play in the aetiology of infant gastroenteritis caused by Candida albicans, C. albicans and the rarely pathogenic, Saccharomyces cerevisiae were studied by three different methods. Both types of yeast significantly depressed the lactose-hydrolysis activity of beta-galactosidase, and both depressed lactose hydrolysis in the ligated small intestine of infant rabbits, either in intact animals allowed to survive for 10 h, or in a physiological bath for 20 h. The depression of lactose activity was not temperature dependent; living and inactivated yeast preparations produced comparable degrees of depression of enzyme activity. It is concluded that the depression of lactose hydrolysis is not a virulence factor of C. albicans, but contributes to the often observed disaccharide intolerance associated with candida gastroenteritis in infants.