Candidacidal activities of the glucose oxidase-mediated lactoperoxidase system

Objective rpose of this study was to investigate the candidacidal activity of the glucose oxidase-mediated lactoperoxidase system at various levels of glucose and glucose oxidase. a albicans ATCC strains 18804, 10231, 11006, bovine lactoperoxidase (25 and 50 μg/mL), and KSCN (1 mM) were used. Different levels of glucose oxidase (1, 5, 10, and 20 units/mL) and glucose (0.03, 0.3, and 3.0 mg/mL) were added to complete the system. The candidacidal activity of the system was examined by preincubating its components for 0–60 min, and then with C. albicans. Candidacidal activity was determined by comparing the numbers of CFU and calculating the percent loss of cell viability. s stem displayed 13.9–27.4% (without preincubation) to 28.6–34.3% (preincubation for 60 min) loss of viability at 25 μg/mL of bovine lactoperoxidase, 10 units/mL of glucose oxidase, and 0.03 mg/mL of glucose; similar results were obtained with 20 units/mL of glucose oxidase or 0.06 mg/mL of glucose. The candidacidal activity of the system increased markedly as the glucose concentration increased. The candidacidal activity displayed 87.2% (without preincubation) to 100.0% (preincubation for 60 min) at 3.0 mg/mL of glucose. At 3.0 mg/mL of glucose, the system containing 1 or 5 units of glucose oxidase also showed significant levels of candidacidal activity. sions ndidacidal activity of the glucose oxidase-mediated lactoperoxidase system at physiological concentrations of salivary glucose was moderate, but was greatly elevated with increases of glucose level.