Saccharomyces cerevisiae KNU5377 with multiple stress tolerance and its potential as a worldwide on-site industrial strain for alcohol fermentation

Abstract

Saccharomyces cerevisiae KNU5377 was examined to assay the recovering capacity against heat and other stressors. Along with a particular fermentation ability that is able to produce ethanol even at high temperature such as 40°C with a comparable rate to the fermentation at 33°C, this strain also exhibited higher viability than a reference strain owing to its own thermotolerance that conferred the survival after the severe heat shock at 60°C for 30 minutes. Furthermore, this strain showed outstanding tolerances against H2O2, ethanol and some chemical compounds. But, especially due to the thermotolerance, this strain has been suspected of other species of yeast. However, ITS (intemally transcribed spacer) 1 and 2 sequencing data confirmed this strain was a typical strain of S. cerevisiae. The outstanding tolerances to various environmental stressors indicate this S. cerevisiae KNU5377 is enough to use both as an on-site potential strain for world-wide alcohol fermentation industry and as a model strain for researches into the routes to acquire the tolerance to various stressors.