Абстрактный

Evaluation of 64oC and 76oC dry saunas as an environment for survival and growth of mesophilic and thermophilic bacteria

Jae Ran Seo, Bong Su Kim, Doo Hyun Park

In this study, the diversity and variations of bacteria that were sampled from the floor of dry saunas operated at 64°C and 76°C for 6 days (Monday–Saturday) wereanalyzed to determineif the bacteria contaminating the dry saunas can grow, survive, or die. Bacteria sampled from the 64°C sauna grew at 45°C and 60°C but those from the 76°C sauna didnot growat either45°C or60°C. Sixteen and eightspecies of bacteria grewat 45°C and 60°C,respectively. Eight of 16 species grown at 45°C werethermophiles and all bacteria grown at 60oCwerethermophiles. DNA of non-growing bacteria sampled from a 76°C sauna wasdirectly extracted and analyzed by temperature gradient gel electrophoresis (TGGE). The non-growing bacteria included13 species based onthe band number of16S-rDNA separatedby TGGE. Thermophilescontaminating the64°C sauna were more frequently detected than mesophilesover the6 experimental days. Most of the mesophiles may have temporarily survivedand some of thermophilic bacteria survived for 4–5 days during sampling for the 6 days,whereas all bacteria contaminating the76°C sauna may lose their physiological function in a short time by drying out.