Fungal direct production of ethanol from high concentration of pulps by ethanol-fermenting white-rot fungus Phlebia sp. MG-60

White-rot fungus Phlebia sp. MG-60 was tried to ferment of high solid loading of hardwood kraft pulp (2, 5, 10, 20% w/w) without addition of cellulase. In all conditions, ethanol production was reached at maximum value within 240 h incubation. From the 2% (w/w) of UHKP, 8.6 g/L ethanol was produced, it was equivalent to the conversion rate at 72.1% of theoretical maximum. From 5% (w/w) of UHKP, 19.6 g/L ethanol was produced, it was equivalent to 61.7% of theoretical maximum. The highest ethanol concentration was observed in the culture with 10% of UHKP, 25.9 g/L ethanol indicating 46.7% of theoretical maximum. So far, ethanol concentration produced by Phlebia sp. MG-60 was increased in a substrate concentration-dependent manner. On the other hand, from the culture with 20% of UHKP, the produced ethanol concentration was 14.4 g/L indicating only 12.9% of theoretical maximum. Solubilization of 10% of UHKP was observed, however, there is no solubilization in 20% of UHKP although growth of the fungal mycelium was observed. The highest FPase activity was observed in the culture with 5% (w/w) UHKP, and the culture with 2 and 10% of UHKP also accumulate the FPase activity. However, the production of the FPase in 20% of culture was severely low revel. This phenomenon might be caused by the water contents of substrate. In this presentation, the UV-mutants derived from protoplasts of MG-60 will be screened for improvement of fermentability.