I纤维素降解菌的筛选及特性研究摘要生物堆肥是大部分养殖场固废资源化利用的主要手段，具有投资小、效益高、有机固体废弃物重复资源化利用效率高等优点，但堆肥过程中也存在一些缺陷，如发酵周期长、有臭味、纤维素木质素分解不彻底等。牛粪中含有大量未能消化的纤维素和半纤维素，它们是影响堆肥腐熟进程、决定其堆肥产品质量的关键因素。因此，在牛粪堆肥发酵中选择添加合适的堆肥发酵菌剂和高效纤维素降解菌剂，是解决畜禽粪便堆肥周期长，降解率低等问题的有效途径。本研究采用富集培养及纯培养法从牛粪中将纤维素降解细菌进行分离并分析其降解特性，以期获得一些高效纤维素降解菌。采用水解圈法和3，5-二硝基水杨酸（DNS）法进行菌株筛选与酶学特性研究，结合形态学方法对其初步鉴定，分子生物学方法对其鉴定其种属，共得到降解效果良好的菌株3株，分别命名为DH01、DH02、DC02，其中DH01为枯草芽孢杆菌，其纤维素酶活性最高；DH02为苏云金芽孢杆菌，纤维素酶活性次之；IIDC02为贝莱斯芽孢杆菌，纤维素酶活性低于前两者。三种菌株均能不同程度分解纤维素，因此，可为牛粪堆肥发酵提供菌种思路，具有重要应用价值。关键词：纤维素降解菌，纤维素酶，分离，酶学特性IIIAbstractBiologicalcompostingisthemainmethodfortheutilizationofsolidwasteresourcesinmostfarms.Ithastheadvantagesoflowinvestment,highefficiency,andhighefficiencyinthereuseoforganicsolidwaste.However,therearealsosomeshortcomingsinthecompostingprocess,suchaslongfermentationcyclesandOdor,incompletedecompositionofcelluloseandlignin,etc.Cowmanurecontainsalargeamountofundigestedcelluloseandhemicellulose,whicharethekeyfactorsthataffectthematurityofcompostanddeterminethequalityofthecompostproduct.Therefore,selectingandaddingappropriatecompostingfermentationinoculantsandhigh-efficiencycellulosedegradinginoculantsinthecattlemanurecompostingfermentationisaneffectivewaytosolvetheproblemsoflongcompostingcycleoflivestockandpoultrymanureandlowdegradationrate.Inthisstudy,enrichmentcultureandpureculturemethodswereusedtoisolatecellulose-degradingbacteriafromcowmanureandanalyzetheirdegradationIVcharacteristics,inordertoobtainsomehigh-efficiencycellulose-degradingbacteria.Usinghydrolysiscirclemethodand3,5-dinitrosalicylicacid(DNS)methodforstrainscreeningandenzymaticcharacteristicsresearch,combinedwithmorphologicalmethodsforpreliminaryidentification,molecularbiologicalmethodstoidentifyitsspecies,atotalofThreestrainswithgooddegradationeffectswerenamedDH01,DH02,andDC02.Amongthem,DH01isBacillussubtiliswiththehighestcellulaseactivity;DH02isBacillusthuringiensis,followedbycellulaseactivity;DC02isBacillusvelezsBacillus,cellulaseactivityislowerthantheformertwo.Thethreestrainscandecomposecellulosetodifferentdegrees,sotheycanprovidestrainideasforcattlemanurecompostingandfermentation,whichhasimportantapplicationvalue.Keywords:cellulolyticbacteria，Cellulase，isolation，enzymaticpropertiesV目录1.引言................................................................................................................................................................12.材料与方法....................................................................................................................................................22.1试验材料................................................................................................................................................22.1.1样品来源....................................................................................................................................22.1.2培养基........
