Antifungal Activity of Monolaurin Against Candida albicans In vivo

Objectives: Monolaurin is a natural compound found in coconut oil that has been known for its broad antimicrobial activities. The aim of this study was to evaluate the antifungal activity of monolaurin against Candida albicans in vivo using a novel bioluminescent model to longitudinally monitor oral fungal infection.
Methods: Oral fungal infection in vivo was performed using bioluminescent engineered C. albicans (SKCa23-ActgLUC) on 6-7 weeks old, 15 inbred Balb/c mice. The antifungal activity of monolaurin was determined by comparing three groups of mice (n=5 in each group): monolaurin (12.5 mM; equivalent to 100 x MIC), vehicle control (PBS), and positive control (nystatin 100 mM). All mice were rendered immunosuppressed with cortisone acetate (225 mg/kg) and oral topical treatments were applied for 30 sec, 2x/ day for 5 days. IVIS imaging was used to monitor the progression of infection over a 5-day period.Total photon flux and ex vivo microbiological analysis of the excised tongues were used to determine the overall fungal burden among the tested groups.
Results: Oral topical treatments of monolaurin have resulted in a significant decrease (p<0.05) in the total photon flux over 4 and 5 days post-infection in comparison to the vehicle control group. Furthermore, monolaurin treated group had a significant decrease in colony formation unit (CFUs)/ml/ gram of tongue tissue compared to the vehicle control.
Conclusions: Our findings support monolaurin as a promising antifungal natural compound, which may translate to its future use in clinical trials for the treatment of oral candidiasis.