The Study On Producing Ethanol From Jerusalem Artichoke

This study got 14 sorts of microorganism bacterium through general preliminary and second screening for chosing several different culture mediums. The B02 has the highest enzyme activity, the I(endoinulinase) is 4.34U·mL^-1,and the S(exoinulinsase) is 5.97U·mL^-1. The B02 strain was identified as the penicillium through the flat colonial morphology and the Microscopic observation.To obtain strains that are able to efficiently produce ethanol directly from Jerusalem artichoke material, the protoplast fusion technique was used and some appropriate conditions were chosen for the protoplast preparation and fusion. The hybrids strain was constructed between Saccharomyces cerevisiae and a penicillium strain which comes from filtration for high-yielding inulinase. The abilty of inulinase and the alcohol producing, and the genetic stability were determined after detected the fusants optionally. The superior strain called R8 was chosen to do the alcoholic fermentation. Finally, the yield of alcohol is 41.16% and the raw material utilization is 75.52%.The strain called R8 which can produce inulinase and alcohol was chosen to optimize the alcoholic fermentation in order to get high-yielding alcohol culture conditions. Using six single factor experiments and the orthogonal test obtains the optimum condition is: 160g·L^-1JAE, 25g·L^-1BE, 8g·L^-1 NH₄H₂PO₄, 0.1g·L^-1 ZnCl₂, PH6.0, 30℃, 180rpm. Finally, the yield of alcohol is 46.30% and the raw material utilization is 84.96%.Using the response surface data processing software Design-expert to optimize the carbon and the nitrogen source of the culture medium. At last, the carbon source concentration is 150.70g·L^-1JAE,and the nitrogen source concentration is 35.67g·L^-1 BE,15.08g·L^-1 NH₄H₂PO₄, the yield of alcohol is 51.46% and the raw material utilization is 94.8%.