Study on sugarcane bagasse pretreatment and high thermotolerable yeast strain

纤维素燃料酒精技术的开发与利用一直是国内外研究的热点，而如何降低纤维素燃料酒精的生产成本越来越成为其产业化发展的关键。 本论文对纤维素预处理方法及耐高温酵母的选育进行了研究。提出酸、碱法预处理甘蔗渣，即甘蔗渣充分吸水后挤出多余水分，再分别浸泡酸、碱液20min，对多余的酸、碱回收，其用量降低90%。采用酸法对甘蔗渣进行预处理最佳处理条件为：1%的H2SO4，105℃处理40min。对预处理后的蔗渣进一步酶解，还原糖得率为16.3%。采用碱法对甘蔗渣进行预处理最佳处理条件为：2%的NaOH，105℃处理40min。对预处理后的蔗渣进一步酶解，还原糖得率为34.7%。通过扫描电子显微镜观察比较，...The research and production of alcohol from lignocellulosic biomass has become the world hotspot recent year. How to reduce the production cost is become more and more important for its industrialization. In this research, the pretreatment of sugarcane bagasse and ethanol fermentation of sugarcane juice were studied. The bagasses were firstly dipped into water and absorbed water fully. Then it w...学位：理学硕士院系专业：生命科学学院生物学系_微生物学学号：2162007115188

Study on Hydrogen Production Activity of Klebsielal oxytoca HP1 and Stability of Its Soluble Hydrogenase under Atmosphere with O_2

目的:考察产酸克雷伯氏菌(Klebsielal oxytoca HP1)耐氧产氢特性及其可溶性氢酶的氧耐受特性。方法:研究K.oxytoca HP1在不同气相氧浓度条件下利用葡萄糖(1%,m/v)、丙酮酸钠(0.5%,m/v)及甲酸(0.1%,v/v)等底物产氢活性的以及K.oxyto-ca HP1可溶性氢酶在空气及氧饱和溶液中催化产氢活性。结果:K.oxytoca HP1在葡萄糖(1%,m/v)底物中具有较高耐氧产氢活性,6h内在气相氧浓度为5%、10%和21%条件下的氢产量分别为厌氧条件下的20.9%、13.7%、8.3%;K.oxytoca HP1可溶性氢酶在空气中孵育12h后,其活性残余85.4%,在氧饱和溶液中活性损失一半约3h。结论:试验结果提示K.oxytoca HP1具有耐氧产氢特性,其可溶性氢酶具有较高氧耐受性,在氢能源的开发中具有潜在的应用前景。Objective: To study the hydrogen production activity of K. oxytoca HP1 under condition with oxygen stress and the oxygen tolerance ability of its soluble hydrogenase. Method: The hydrogen production activity of K. oxytoca HP1 incubated in glucose (1%,m/v), sodium pyruvate (0.5%,m/v)or formate (0.1%,v/v) under atmosphere with 0%,5%,10% and 21% O2 were studied on, and the remain activity of its soluble hydrogenase incubated in air or pure O2 during 0-12h were studied on. Result: The results show that K. oxytoca HP1 has high hydrogen production activity in glucose (1%,m/v) substrate under atmosphere with oxygen. Compared to in anaerobic condition, the hydrogen production of K. oxytoca HP1 under atmosphere with 5%, 10% and 21% oxygen was 20.9%,13.7% and 8.3% respectively in 6h. The soluble hydrogenase from K. oxytoca HP1 exhibits considerable oxygen toleration ability, the remain activity was 85.4% after the hydrogenase exposure to air 12h and its activity lost half after the hydrogenase exposed to oxygen 3h. Conclusion:These results suggest that K. oxytoca HP1 and its soluble hydrogenase have potential to be applied in hydrogen production and application.福建省青年科技人才创新项目资助(No.12005J003