2023學(xué)年完整公開課版ApplicationsOfEnzymes2

生物技術(shù)及應(yīng)用專業(yè)教學(xué)資源庫EnglishForBiotechnology專業(yè)英語Chapter3EnzymeEngineeringUnit5

ApplicationsOfEnzymesApplicationsOfEnzymes

Enzymesareusedinindustriesindifferentways.InDairyindustryInDetergentIndustryInStarchIndustryInBrewingIndustryInWineIndustry酶以不同的方式用于工業(yè)乳品工業(yè)洗滌劑行業(yè)淀粉工業(yè)釀酒行業(yè)葡萄酒行業(yè)IndustrialUsesOfEnzymesApplicationsOfEnzymes

Foralongtime,calfrennethasbeenusedinthedairyindustry.Inrecentyears,calfrennetsarereplacedbymicrobialrennets(e.g.Mucormichei).Theyareacidaspartateproteases.TheyslightlydifferfromcalfrennetsastheydependforreactionwithcaseinonCa++,temperature,pH,etc.長期以來，小牛凝乳酶一直用于乳品工業(yè)。近年來，小牛凝乳酶被微生物凝乳酶（如米氏毛霉）所取代。它們是酸性天冬氨酸蛋白酶。它們與小牛凝乳酶稍有不同，因為它們與酪蛋白的反應(yīng)取決于鈣離子、溫度、pH值等。InDairyindustryApplicationsOfEnzymes

Lactase(producedbyBacillusstearothermophilus)isusedforhydrolysisoflactoseinwheyormilk,andlipaseforflavourdevelopmentinspecialcheeses.乳糖酶（由嗜熱脂肪芽孢桿菌產(chǎn)生）用于水解乳清或牛奶中的乳糖，脂肪酶用于特殊奶酪的風(fēng)味開發(fā)。InDairyindustryApplicationsOfEnzymes

Duringnormalwashingproteinaceousdirtoftenprecipitatesonsolidclothsandproteinsfacilitatetoadherethedirtontextilefibresandmakestainsoncloths.Thesestainsaredifficulttoremovefromclothes.Nevertheless,itcanbeeasilyremovedbyaddingproteolyticenzymestothedetergent.洗滌劑行業(yè)在正常的洗滌過程中，蛋白質(zhì)污垢通常會沉淀在固體布料上，蛋白質(zhì)有助于將污垢粘附在紡織纖維上，并在布料上留下污漬。這些污漬很難從衣服上除去。然而，在洗滌劑中加入蛋白水解酶很容易去除。InDetergentIndustryApplicationsOfEnzymes

Itattackspeptidebondsandtherefore,dissolvesprotein.ThealkalineserineproteaseobtainedfromB.licheniformisismostwidelypreferredtouseindetergent.Inaddition,theserineproteaseofB.amyloliquefaciensisalsousedforthispurpose.Itcontainsa-amylase,hencetosomeextentitmaybeadvantageous.它攻擊肽鍵，從而溶解蛋白質(zhì)。從地衣芽孢桿菌中提取的堿性絲氨酸蛋白酶被廣泛應(yīng)用于洗滌劑中。此外，解淀粉雙歧桿菌的絲氨酸蛋白酶也用于此目的。它含有α-淀粉酶，因此在某種程度上可能是有利的。InDetergentIndustryApplicationsOfEnzymes

Ithasbeenmentionedearlierthathydrolysisofstarchbeganintheearly1960stopreparedextroseandglucosesyrups.Furthermore,forcompleteacidhydrolysisofstarchtodextroseglucoamylasewascoupledwithbacteriala-amylase.Currently,variousenzymaticprocessesareappliedtovariousproducts.淀粉工業(yè)早在20世紀(jì)60年代初，人們就已經(jīng)提到了淀粉的水解，以制備葡萄糖和葡萄糖糖漿。此外，為了使淀粉完全酸水解為葡萄糖，還將葡萄糖淀粉酶與細菌α-淀粉酶偶聯(lián)。目前，各種酶法工藝應(yīng)用于各種產(chǎn)品。InStarchIndustryApplicationsOfEnzymes

Theuseofstarchdegradingenzymeswasthefirstlarge-scaleapplicationofmicrobialenzymesinfoodindustry.Mainlytwoenzymescarryoutconversionofstarchtoglucose:alpha-amylasecutsrapidlythelargealpha-1,4-linkedglucosepolymersintoshorteroligomersinhightemperature.Thisphaseiscalledliquefactionandiscarriedoutbybacterialenzymes.淀粉水解酶是微生物酶在食品工業(yè)的第一次大規(guī)模應(yīng)用。在食品工業(yè)中，主要有兩種酶將淀粉轉(zhuǎn)化為葡萄糖。在高溫下α-淀粉酶迅速將α-1,4-糖聚合物分解為低聚物，這一過程稱為液化，是由細菌酶完成的。InStarchIndustryApplicationsOfEnzymes

Inthenextphasecalledsaccharification,glucoamylasehydrolysestheoligomersintoglucose.Thisisdonebyfungalenzymes,whichoperateinlowerpHandtemperaturethanalpha-amylase.下一階段叫糖化，糖化酶將低聚物轉(zhuǎn)化成葡萄糖，這一過程在比α-淀粉酶低些的pH和溫度下進行，由真菌酶完成。InStarchIndustryApplicationsOfEnzymes

Glucoseisomeraseisanimportantenzymeusedcommerciallyintheconversionofglucosetofructoseviaisomerisation.Fructoseisusedinthepreparationoffructosesyrup.Thereactionmixtureattheendcontains42%fructose,52%glucose,and6%dextrins.Themixtureissweeterthanglucoseandassweetassucrose.Now,techniqueshavebeendevelopedtoobtain55%fructoseconcentrationinsyrup.葡萄糖異構(gòu)酶是一種重要的酶，商業(yè)上用于通過異構(gòu)化將葡萄糖轉(zhuǎn)化為果糖。果糖用于制備果糖糖漿。最后的反應(yīng)混合物含有42%的果糖、52%的葡萄糖和6%的糊精。這種混合物比葡萄糖甜，像蔗糖一樣甜。現(xiàn)在，技術(shù)已經(jīng)發(fā)展到在糖漿中獲得55%的果糖濃度。InStarchIndustryApplicationsOfEnzymes

Enzymesusedinthebrewingindustryarea-amylase,b-glucanaseandproteasewhicharerequiredformaltinsubstitutionofbarley.SourceoftheseenzymesisB.amyloliquefaciens.a-amylaseisnotrequiredforliquefactionorbrewingadjunctsandb-glucanasealleviatesfiltrationproblemsduetopoormaltqualityandneutralproteasehelpsintheinhibitionofalkalineproteasebyaninhibitor.釀酒行業(yè)釀酒工業(yè)中使用的酶是a-淀粉酶、b-葡聚糖酶和蛋白酶，這些酶是麥芽替代大麥所必需的。這些酶的來源是解淀粉雙歧桿菌。液化或釀造輔料不需要α-淀粉酶，β-葡聚糖酶可緩解因麥芽質(zhì)量差而產(chǎn)生的過濾問題，而中性蛋白酶有助于通過抑制劑抑制堿性蛋白酶。InBrewingIndustryApplicationsOfEnzymes

Pecticenzymesareutilisedinthewinebusinessfortopyieldofproductofimprovedquality.Thepecticenzymesarepectintranseliminase(PTE),polymethylgalacturonase(PMG),polygalacturonases(PG),pectinesterase(PE),etc.However,teaseglucoamylase,etc.葡萄酒行業(yè)果膠酶用于葡萄酒行業(yè)，以提高產(chǎn)品的最高產(chǎn)量和質(zhì)量。果膠酶有果膠轉(zhuǎn)胺酶（PTE）、聚甲基半乳糖醛酸酶（PMG）、多聚半乳糖醛酸酶（PG）、果膠酯酶（PE）等。然而，纖維素酶與不同的酶（如蛋白酶、糖化酶等）結(jié)合后，效果更佳.InWineIndustryApplicationsOfEnzymes

Industrialenzymemarketgrowssteadily,Thereasonforthisliesinimprovedproductionefficiencyresultingincheaperenzymes,innewapplicationfieldsandinnewenzymesfromscreeningprogrammesorinengineeredpropertiesoftraditionalenzymes.工業(yè)酶制劑市場穩(wěn)步增長，源于生產(chǎn)效率的提高和價格的降低，源于新的應(yīng)用領(lǐng)域，源于通過篩選而來的新酶的應(yīng)用，源于具有工程特性傳統(tǒng)的酶的應(yīng)用。FuturetrendsinindustrialenzymologyApplicationsOfEnzymes

Newapplicationsaretobeexpectedinthefieldoftextiles,newanimaldietslikeruminantandfishfeed.Itcanbeexpectedthatbreakthroughsinpulpandpaperwillmaterialise.Theuseofcellulasestoconvertwastecelluloseintosugarsandfurthertoethanolbyfermentativeorganismshasbeenamajorstudytopicforyears.Increasingenvironmentalpressure