Sunday, May 3, 2009
2-18
Yeast strains for ethanol production from lignocellulosic hydrolysates in situ detoxification
Yang XIushan and Tian Shen V. College of Life Science, Capital Normal University, No.105, Xisanhuan North Road, Haidian District, Beijing, China, Beijing, China
Yeast strains of Y1, Y4, and Y7 exhibiting high conversion efficiency of sugars and high ability of tolerating/metabolizing inhibitors in the dilute-acid lignocellulosic hydrolysates developed in our lab were presented in this work. Strains Y1 and Y4 consumed glucose completely in dilute-acid lignocellulosic hydrolysate in situ detoxification within 24h and the highest ethanol yield reached to 0.49g and 0.45g ethanol/g glucose, corresponding to the maximum theoretical value of 96% and 88.2%, respectively. Strain Y1 could metabolize xylose to xylitol with the yield of 0.64g /g xylose, whereas, Y4 was not able to utilize xylose as a substrate. Strain Y7 could consume sugars (glucose and xylose) in hydrolysate in situ detoxification within 72h and a high ethanol yield (equivalent to 93.6% of the maximum theoretical value) was also achieved. Y7 is one of the most efficient yeast strains reported so far for ethanol production from non-detoxified dilute-acid lignocellulosic hydrolysates. It may offer huge potential for improving the economics of the bio-ethanol production from lignocellulosic hydrolysates.