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1、手性内酯论文:酶法合成生物素中间体手性内酯和拆分萘普生的研究【中文摘要】本论文主要研究了生物酶催化法合成生物素重要中间体手性内酯和固定化酶拆分萘普生,此外还对从生物素废水中回收原料醇胺进行了初步的研究。首先筛选到对底物二甲酯具有选择性水解能力的微杆菌,研究了各种条件对于酶的催化活性的影响,其中包括底物浓度、pH值、温度、有机溶剂、分散剂、添加剂等。实验结果显示酶的催化活性在底物浓度为10mg/mL,pH为7.5的磷酸盐缓冲溶液中转化率较高,反应与温度呈正相关,在40℃时转化率较高,达到90%以上。添加聚乙二醇(6000)和p-环
2、糊精对酶的催化效果有促进作用,其中p-环糊精效果明显,在相同的实验条件下,比不添加的转化率提高40%左右。通过酶催化结合化学【英文摘要】Biotinisanimportantvitaminwhichisessentialtothenormalphysiologicalactivitiesofanimalsandhumanlife.Thisthesisstudiesthebiocatalyticsynthesisofimportantintermediateofchirallactoneof(+)-biotin.Firstwesc
3、reenedamicro-bacteriumwhichcanselectivelyhydrolyzethesubstrateofdiester.Thenwestudiedthereactionconditionswhichcanaffecttheenzymeactivity,includingsubstrateconcentration,pH,temperature,organicsolvents,dispersants,additives,etc.Experimentalresultsshowthattheenzyme-cat
4、alyzedhydrolysisprocessshowshighconversionratewhenthesubstrateconcentrationis10mg/mLandpHvalueis7.5.Thereactionispositivelycorrelatedwithtemperatureandtheconversionhasreached90%whenthetemperatureis40℃.Theadditivesofpolyethyleneglycol(6000)andP-cyclodextrincanefficien
5、tlyimprovetheconversion.Theconversionisincreasedby40percentbyaddingβ-cyclodextrinintothereactionsystemcomparedwiththatwithoutβ-cyclodextrin.Thee.e.valueofchirallactoneobtainedbyenzymecatalysisis97.9%,thesameasthestandardindustrialsample.Andthespecificrotationofbiotin
6、lactoneis+60.5℃.Thesecondpartofthethesisexaminedhowtoisolateanimportantrawmaterialofalkanolaminefromthewastewaterof(+)-biotinproduction.Amongthetriedmethods,theonewhichextractthealkanolaminewithethylacetate,thenwashthecrudealkanolaminewithmixturesolventofmethanolandm
7、ethylenechlorideisthemostsuccessfulmethod.Therecoveryyieldandpurityaremuchhigherthanothermethods.Thethirdpartofthethesisstudiestheresolutionofracemicnaproxenbyanimmobilizedlipase.Inatrappedaqueous-organicbiphasicsystem,lipasefromCandidarogusaiseffectivelyimmobilizedo
8、nMCM-41mesoporousmolecularsieve.Theimmobilizationefficiencyis100%.Underthesamecondition,theimmobilizedenzymeactivityincrease5-foldc