IADR Abstract Archives
Shrimp Chitosan Inhibits Growth of Common Oral Candida Species
Objectives: Candidiasis is a common opportunistic infection in the oral cavity. Because resistance to current antifungal drug is increasing, we aimed to search for natural products with antifungal activity. Here, we examine the activity of shrimp chitosan, a natural product with antimicrobial activity, against common oral Candida species in vitro.
Methods: Two types of shrimp chitosan, oligomer (7,000-9,000 Da; 80 mesh) and polymer (900,000-1,000,000 Da; 40 mesh), were tested against Candida albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. dubliniensis, and C. krusei. Log-phase Candida cultures were incubated with serial dilutions of chitosan for 24 hours and plated on rich media to determine the Minimal Fungicidal Concentrations (MFC). Since chitosan was dissolved in 1% acetic acid, serial dilutions of acetic acid were also tested as a solvent control.
Results: Candida species failed to grow after exposure to acetic acid at concentrations above 0.25%, but the growth was not inhibited at 0.125%. Thus, the MFCs of chitosan were determined at acetic acid concentrations of 0.1% and lower. The MFCs of shrimp chitosan were in the range of 1.5-3 mg/ml for most species, although over 90% of Candida cells were killed at 0.75 mg/ml. However, neither types of chitosan tested could inhibit the growth of C.glabrata.
Conclusions: Shrimp chitosan is active against the majority of common oral Candida species. Further investigations will reveal its potential benefit as an antifungal agent for applications in the oral cavity.
Methods: Two types of shrimp chitosan, oligomer (7,000-9,000 Da; 80 mesh) and polymer (900,000-1,000,000 Da; 40 mesh), were tested against Candida albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. dubliniensis, and C. krusei. Log-phase Candida cultures were incubated with serial dilutions of chitosan for 24 hours and plated on rich media to determine the Minimal Fungicidal Concentrations (MFC). Since chitosan was dissolved in 1% acetic acid, serial dilutions of acetic acid were also tested as a solvent control.
Results: Candida species failed to grow after exposure to acetic acid at concentrations above 0.25%, but the growth was not inhibited at 0.125%. Thus, the MFCs of chitosan were determined at acetic acid concentrations of 0.1% and lower. The MFCs of shrimp chitosan were in the range of 1.5-3 mg/ml for most species, although over 90% of Candida cells were killed at 0.75 mg/ml. However, neither types of chitosan tested could inhibit the growth of C.glabrata.
Conclusions: Shrimp chitosan is active against the majority of common oral Candida species. Further investigations will reveal its potential benefit as an antifungal agent for applications in the oral cavity.