Isolation and screening of thermotolerant yeast capable of producing ethanol at high temperatures were described in this study. Soil, plant decay and sugarcane bagasse samples from sugarcane plantations and sugar factories in Northeastern part of Thailand were collected to the isolation of thermotolerant yeast a total of 84 isolates and and 43 isolates ability to grow at temperature up to 45 ˚C.
Among the 43 isolates of thermotolerant yeast obtained in this study, 19 isolates showed strong fermentation activity at high temperatures (37, 40 and 45oC), as measured by the accumulation of CO2 gas in Durham tube.Thus, these isolates were subjected to the ethanol production tests by culturing the yeast cell in the YM medium containing 16% (w/v) glucose