Impact of lysozyme and lactoferrin on oral Candida isolates exposed to polyene antimycotics and fluconazole

OBJECTIVE: To assess the antifungal activity of lysozyme and lactoferrin on 10 oral isolates each of Candida albicans and Candida tropicalis following their brief exposure (1 h) to subtherapeutic concentrations of two polyene drugs - nystatin, amphotericin B, and an azole - fluconazole. METHODS: Yeasts were sequentially exposed to subtherapeutic concentrations of antifungals and then to either lysozyme or lactoferrin and the viability evaluated by quantifying colony-forming units. RESULTS: The exposure of both C. albicans and C. tropicalis isolates to all three antifungal agents significantly increased their susceptibility to lysozyme (P < 0.05) but not to lactoferrin. Exposure to the two polyene drugs had a lesser impact on the lysozyme susceptibility of both Candida species compared with the azole drug. Both interspecies and intraspecies sensitivity to lysozyme was noted and C. albicans was less susceptible than C. tropicalis . CONCLUSIONS: Lysozyme, in addition to being a potent natural antifungal agent, may act synergistically with the studied antimycotics.