L-阿拉伯糖異構酶的酶學性質及酶法制備塔格糖研究.pdf

1、分類號江尚蓯。善碩士學位論文題耳：L，阿拉伯糖異構酶的酶學性質及酶法制糖塔格禧研究英文并列題目：PropeniesofL—ArabinoseIsomeraseandEnzyma士主cpreparationofD一魂atose密級硬究生：整萋羹專駐：，叁塞魁璺研究方向：一患蝗整苤蕉盒昌蟲盥鏖趟導師：。，逸鎏熬爨，揍魯小組成員：學位授予日期：答辯委員會主艨：夏文水江南大學建垃二無撼市二00六年六月江南大學碩：L學位論文AbatractD一切

2、gatose，ararenaturalhexoketose，isoneoftheraresugars，whicharedefinedasmonosaccharidesandtheirderivativesmatrarelvexistinnatI鵬0namolecularleveLDtagatoseissmlctIlrallyidenticaltoD—f砘ctose，exceptforaninversionofthehydroxyla11

3、dhydrogengmupsatthefourthcarbonatomThesweetnessofD—tagatoseis92％matofsucmse、vitllasimilartaSteIthasbeentestedthatDtagatosecanbeusedinfoodindustnrGRASD—ta_髀tosehaslowcaloricvalue，inaddj石on，“canpreventtootlldecayhasnoe丘bct

4、onplasmaglucoseleVels，impmVehealtllybacteri啪ForthesereaSons，D—tagatosehaSreceivedinterestrecentlyasanoncaloricsweetenersubstituteforsucroseItisveryimponallttoestabIishaf酤t，conveniema11de丘cctivememodfordataprocessin2Accor

5、diIlgtothecysteine—carbazoletestintroducedbyDische，westudiedtestconditionsandsetupasimpleaIldconvenient，reliablemomordAstramof￡口cf06口c刪kjSKl002whichcanDroduceLarabinoseisomerasewasstoredinollrlaboratorvtTheeabctofn喇entsa

6、IldotherculnlralconditionsontlleLarabinoseisomerasewerestudiedTheoptimalmediumcompositionsandculturalcondmonswere(2／L)：maltodex岫n28，yeaStextract10，comsteepliquor22，CH3COONa10，K3P0402，NaCl00l，F(xiàn)eS047H20O01，MgS047H20O2，ⅣmS0

7、42H20O05，Larabinose25Theoptim啪f鋤entationconditions、vereinitialpH84，cultivatetemperatLlre37℃，inoculationvolme3％，fe衄en詛tiontime12hTheenzvIlleactivitvreached728U，mLThecellsweredisruptedbysonicationaIldcemrifuged，山esupemlata

8、mwasfIlrtherpuri矗edbya￡砌onj啪sulfate舶ctionation，diaiysjsPjropeniesof出eL—arabinoseisomerasewerealsostudiedTheoptimalreactiontempemturea11dpHofL一啪binoseisomemsewere60℃and7O，respectivelMTheenzymewasstablewithinpH4O一8Ounder30

9、—60℃TheadditionofMn2，M一，F(xiàn)ez十ionse11llallcedtlleeIlzymeactivi饑Ⅵ，hereas廿1eadditionofB一，Zn肘ionsinhibited“completelyWithD—galactoseaSsubstrate，Km=119393mmol／L，V。。x135l“∥m證D—tagatosewaSisomerized疔omD—galactoseusingLarabinosei

10、sOmeraseinthreefomls：cell一療eeen巧me，lOand40％(w／w)wetweightwhole—cellEffbctsoftemperamre，en糾me，substrateconcentrationandreactiontimeontheD—galactoseconversionratioweredeteHniIledThesubstrateconcen仕ationwasfoundtobeoptimala

11、t0833mol／LAhigherconversionyieldof389％(w／rW)、vasobtainedaRerabout72hoursbyusing40％(w／w)wetweightwhole—cellFinally，byFTIRSpectmmetertest，wecon靠mledthatLarabinoseisomemsemediatedtheisomerizationofDgaIactoseintoD協(xié)gatoseThep