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1、1Fermentation Engineering 2IntroductionConcept of fermentationConcept of fermentationHistory of fermentationHistory of fermentationTypes of fermentation productsTypes of fermentation productsSteps in industrial fermentationSteps in industrial fermentation3The term fermentation is derived from the La
2、tin verb fervere, to boil, which describes the appearance of the action of yeast on extracts of fruit or malted grain during the production of alcoholic beverages. What is fermentation?4Biochemists opinion (narrow sense) Fermentation is an anaerobic process (“life without air”)where energy is produc
3、ed without the participation of oxygen or other inorganic electron acceptors.5Microbiologists opinion (broad sense) Any process for the production of a product by the mass culture of microorganisms. Definition of Fermentation Fermentation is the chemical transformation of organic substances into sim
4、pler compounds by the action of enzymes, which are produced by microorganisms such as molds, yeasts, or bacteria.7Fermentation is aunique process with great potentialEnvironment friendly Consume less energyEasy to manage 8History of fermentationHistory of fermentation Ethanol fermentation was one of
5、 the first chemical reactions observed by humans. In nature, various types of food go bad as a result of bacterial action. Early in history, humans discovered that this kind of change could result in the formation of products that were enjoyable to consume. 9Made the earliest microscopes which magni
6、fied up to 300X.Discovered micro-organisms.Pioneers in MicrobiologyAnthony van Leeuwenhoek(1632-1723)Leenvenhoek s microscope(1822-1895)(1822-1895)Louis PasteurShowed microbes caused fermentation & spoilageDisproved spontaneous generation of microorganismsDeveloped aseptic techniques12LouisPasteursg
7、ermtheoryOldTheory:spontaneousgenerationmicro-organismsaretheresultofdecayingmatter.NewTheory:germtheorymicro-organismscausedecayingmatter.Pasteurshowedyoucouldkillthemicro-organismsbyapplyingheatPasteurisation.14（1843-1910）Developed pure culture methods.Established a sequence of experimental steps
8、to show that a specific m.o. causes a particular diseaseKochs PostulatesRobert Koch15Singlestrain16The Nobel Prize in Chemistry 1907forhisbiochemicalresearchesandhisdiscoveryofcell-freefermentationEduard Buchner 1860-1917Germany 17 In 1897, Buchner ground up a group of cells with sand until they wer
9、e totally destroyed. Then he extracted the liquid and added it to a sugar solution. His assumption was that fermentation could no longer occur since the cells were dead. But he was amazed to discover that the cell-free liquid did indeed cause fermentation. 18StartfromanancienttimeLargescaleproductio
10、n Early 20th century beverage industry, vinegar, baking yeast, citric (or lactic) acid Late 20th century development of biotechnology from the antibiotic industrialHistory of Fermentation engineering1920Major Products of Industrial MicrobiologyIndustrial and agricultural productsFermented Food and F
11、ood additives Products for human and animal health21Micro-organismscausechangesinthefoodswhich:Extend the shelf life ( preservation ) Producing desirable taste and flavourImprovement of nutritional valueProducing required physicochemical properties22TheproductcaneitherbeThe cell itself: biomassprodu
12、ction.A microorganism own metabolite: aproductfromanaturalorgeneticallyimprovedstrain.23ProductsfromMicroorganismsvinegar24Q: Why antibiotics , amino acid and enzymes could be produced by microbial fermentation ? 2525Typesofmicrobialproducts Primary metabolites produce during growth stageincludeamin
13、oacids,nucleotides,fermentationendproductsandenzymes26 Secondary metabolites produce after growth stagehavenodirectrelationshiptosynthesisofcellmaterialandnaturalgrowthincludeantibiotics,mycotoxins,pigmentet al.272829PrimarymetabolitePrimarymetaboliteMicroorganismMicroorganismSignificanceSignificanc
14、eEthanolEthanolSaccharomyces Saccharomyces cerevisiaecerevisiaealcoholicbeveragesalcoholicbeveragesCitricacidCitricacidAspergillus nigerAspergillus nigerfoodindustryfoodindustryAcetoneandbutanolAcetoneandbutanolClostridium Clostridium acetobutyricumacetobutyricum solventssolventsLysineandLysineandGl
15、utamicacidGlutamicacidCorynebacterium Corynebacterium glutamaciumglutamaciumnutritionaladditivenutritionaladditiveandflavourenhancerandflavourenhancerXanthangumXanthangumXanthomonas Xanthomonas campestriscampestrisindustrialindustrialSecondarymetaboliteSecondarymetaboliteMicroorganismMicroorganismSi
16、gnificanceSignificancePenicillinPenicillinPenicillium Penicillium chrysogenumchrysogenumantibioticantibioticStreptomycinStreptomycinStreptomyces Streptomyces griseus griseus antibioticantibiotic30ContentsP.M.S.MGrowthneeded?YesNoSpeciesspecificity?NoYesProductionstageduringactivegrowthaftergrowthpha
17、seExamplesaminoacid,nucleotide,polysaccharide,vitaminantibiotics,toxin,hormones,pigmentProducedsteadilybycellregulationsdifferencessimilaritiesprimary metabolites vs. secondary metabolites31 Steps in Industrial FermentationScreen the best producing strainPrepare medium and sterilization Optimize pro
18、duction conditionDownstream processing32seed fermentershake flaskstock cultureraw materialsmedium formulationsterilizationrecoverypurificationfermenterairproducts33OutlineofafermentationprocessUpstream processingDownstream processingRaw MaterialsProduction microorganismFermentationProduct purificati
19、onProductEffluent waste34FERMENTATIONProcess ControlFermentation engineeringUPSTREAM PROCESSESDOWNSTREAM PROCESSES35UPSTREAM PROCESSES- Producer microorganism- Inoculum development- Media formulation- Sterilization- Fermentation ProcessFERMENTATIONProcess ControlFermentation engineering36The essenti
20、al components of a fermentor37DOWNSTREAM PROCESSES - product extraction, purification & assay - waste treatment -by product recoveryFERMENTATIONProcess ControlFermentation engineeringThe ratio of recovery to fermentation costs for L-asparaginase: 3.0 ethanol: 0.1638Howaremicroorganismscultivated?Pet
21、riDishesShakeFlasksFermentor39The Fermentation Process40Industrial production of yeast cells4142What are the main problems of current world?Energy FoodEnvironment43“Single-Cell Protein” (SCP)- the production of rich-protein food using single-cell fungi, which, when growing on an inexpensive food sub
22、strate, convert it into proteins of high biological value. 44 Review Questions1. Cite the following scientists outstanding contributions to the fermentation industry: leenvenhoek、Pasteur、Koch and Buchner2. What is fermentation and what are the main components of fermentation engineering?3. What are the primary metabolites and the secondary metabolites? Give the differences between them with examples.
