甜高粱秸秆纤维素降解研究.doc

北方民族大学本科毕业论文（设计）甜高粱秸秆纤维素降解研究第PAGE\*MERGEFORMAT1页甜高粱秸秆纤维素降解研究摘要伴随着经济的不断增长，化石能源在不断减少，而能源需求越来越多，使用化石能源还带来一系列的环境问题。人们在不断寻找新的清洁能源，以取代化石能源，其中由植物纤维素生产的燃料乙醇成为研究热点。本实验以甜高粱秸秆为原料，将其经氨水预处理之后，先后用木聚糖酶和纤维素酶处理，将秸秆中的半纤维素和纤维素转化为还原糖，在木聚糖酶和纤维素酶水解液分别接入红酵母和酿酒酵母，利用还原糖转化成所需产物。实验结果表明，木聚糖酶水解秸秆的最适反应条件为50℃，pH5.0，添加量3000U/g（酶/秸秆），反应12h得到最高的还原糖含量；纤维素酶最适的反应条件为50℃，pH4.5，添加量540U/g（酶/秸秆）的条件下反应36h得到最高的还原糖含量。在两种酶的水解液中分别接入的红酵母和酿酒酵母都得到了较好的生长。关键词：木聚糖酶，纤维素酶，降解，秸秆第PAGE\*MERGEFORMAT2页STUDYONDEGRADATIONOFSWEETSORGHUMSTRAWCELLULOSEAbstractWiththegrowingofeconomy,thefossilenergyisshrinking,thedemandforenergyismoreandmore,theuseoffossilenergyhasbroughtaseriesofenvironmentalproblems.Peoplearelookingforanewcleanenergytoreplacefossilfuels,whichproducedbyplantcellulosefuelethanolbecomearesearchhotspot.Thisexperimenttakethesweetsorghumstrawastherawmaterial,afterammoniapretreatment,successivelytreatedwithxylanaseandcellulase,hemicelluloseandcelluloseofstrawcanbeconvertedtoreducingsugar,thexylanaseandcellulasehydrolysateandrespectivelyconnectedtotheredyeastsaccharomycescerevisiae,makeuseofthereducingsugarintotherequiredproduct.Itshowedthatthexylanasehydrolysisofstrawoptimumreactionconditionof50℃,pH5.0,addingamountof3000U/g(enzyme/straw),12htogetthehighestreducingsugarcontentinreaction;Cellulaseoptimumreactionconditionof50℃,pH4.5,addingamountof540U/g(enzyme/straw)undertheconditionofreaction36htogetthehighestreducingsugarcontent.Respectivelyinthetwokindsofenzymatichydrolysateofaccessofredyeastsaccharomycescerevisiaeandgotabettergrowth.Keywords:xylanase,cellulase,degradation,straw第PAGE\*MERGEFORMAT4页目录第1章文献综述-----------------------------------------------------------------------------------------------11.1研究背景------------------------------------------------------------------------------------------------11.2国内外秸秆的利用现状-------------------------------------------------------------------------------11.2.1国外秸秆利用发展概况-------------------------------------------------------------------------11.2.2国内秸秆利用发展现状-----