Present sterilization methods for biofilms in medical devices have limitations. Therefore, an alternative sterilization method using supercritical carbon dioxide (SC-CO2) was tested on Candida albicans biofilms. The effect of varying pressure, temperature, and treatment time on the inactivation of C. albicans spores in suspensions and in biofilms was examined. The parameters such as treatment time, pressure, and temperature that led to the complete inactivation of C. albicans biofilms ranged 5–20 min, 100–200 bar, and 35–45 °C, respectively. Notably, treatment of SC-CO2 at either 100 bar and 40 °C or 200 bar and 30 °C induced complete inactivation of spores within 5 min. Furthermore, it was found that wet biofilms (0.4 %, w/w) had higher sensitivity to SC-CO2 than dried biofilms. Finally, spore inactivation was confirmed by confocal laser scanning microscopy. In this study, the use of a low-temperature SC-CO2 sterilization method was proven to be effective in fungal biofilm inactivation, and the moisture content of biofilms was revealed to be the key factor for biofilm inactivation.
Bibliographical noteFunding Information:
This work was supported by grants from the Advanced Biomass R&D Center of Korea (2011-0031353) funded through the Korean Government (MSIP) and also from the Ministry of Trade, Industry and Energy (10047873). This research was performed at the Korea University Food Safety Hall for the Institute of Biomedical Science and Food Safety.
© 2015 Springer-Verlag Berlin Heidelberg
- Candida albicans
- Supercritical carbon dioxide