高產(chǎn)2，5-二甲基-4-羥基-3(2H)-呋喃酮酵母菌株的選育及培養(yǎng)環(huán)境的研究.pdf

1、江南大學(xué)碩士學(xué)位論文高產(chǎn)2，5二甲基4羥基3（2H）呋喃酮酵母菌株的選育及培養(yǎng)環(huán)境的研究姓名：張海林申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：發(fā)酵工程指導(dǎo)教師：范文來20090801AbstractAbstract2，5Dimethyl一4hydroxy3(2H)furanone(DMHF)isoneofahigh—gradehydroxyl—furanonearomacompoundsDMHFexhibitsstrawberry—likeflavori

2、ndilutesolutionsand。caramel1ikeflavorinconcentratesDMHFisextensivelyusedasfoodflavoringduetoitslowodorthresholdsandflavorenhancingpropertiesDMHFproductionbymicrobialfermentationhasgoodprospectbecauseofitsexpensivepriceAc

3、complishingbreedyeaststrains謝th11igllproductionofDMHFandstudyonrelatedfactorsintheprocessofDMHFbiosynthesisinthedissertation，n地maincontentsofthisdissertationCallbesummarizedasfollows：(1)Screeingafineyeaststrainproducing3

4、62mg／LDMHFnamedasSX一21neSX21yeaststrainwasidentifiedasPichiaguilliermondifbv18SrDNA(2)Treatedwithultravioletmyandnitrosoguanidine(NTG)，screeingahighproductionmutantofDMHFnamedasNTGSX103IntheculturecontaininglOOg／LDfructo

5、se1，6一diphosphate(FDP)，theconcentrationofDMHFCanreach925mg／L，whichWas15timehigherthanSX21’S(3)StudyonfactorsofDMHFbiosynthesisbyNTGSX一103throughsinglefactorexperiment，F(xiàn)DPasprecursorNaCl，initialpHandrotationalspeedwerekey

6、factorsintheproceesofDMHFbiosynthesisIntheconditionofinitialpH58and250r／minandinthewortcontaining1OOg／LFDPand1209／LNaCI。theconcentrationofDMHFcallreach2052mg／L，whichWas45timehigherthanintheintialcultureIntheculturecontai

7、ning4009／LFDPtheconcentrationofDMHFCanreach7047mg／L，above100mg／Lreportedinpublishedliterature(4)HighconcentrationNaClCangreatlypromoteproductionofDMHFnleconcentrationofDMHFintheculturecontaining1209／LNaClWas26timehighert

8、hanwithoutNaClExogenoussorbitolinsteadingofNaClCallalsopromoteproductionofDMHFgreatlyExogenousCaasanessentialmessengerinsaltstressconditionpromotedincrcasionofDMHFby50％(5)Inhighsaltstresscondition，membranepermeabilitymcr

9、easedbydeterminationofextracellularnucleicacidin260nmand2nitropehenylin420nmIntheprocessoffermentation，F(xiàn)DPalmostwasn’tutilizedbyNTGSX103strainpresentinginfermentationbrothduringthefermentationnleincreaseofmembranepermeab

10、ilityinhighconcentrationofNaCl，promotedFDPitsmetabolitecombiningwithrelatedenzymesofbiosyntheticD^嗄HFandDMHFyieldincreaseIncreasingmembranepermeabilitybyadditionofsurfactantsandorganicsolventsCanalSOpromoteproductionofDM

11、HFMembranepermeabilityWasakeyfactorduringtheprocessofDMHFbiosynthesis(6)AddingexogenousFDPandNADPHintoextractionsofenzymesolutioninextracell，cellandcellmembraneDMHFWasonlyformedinthecellmembraneextraction。nekeyenzymesofb