Friday November 4, 2016

Transcription

1 Friday November 4,

2 Feedback Have you studied biochemistry and microbiology in your earlier studies? (17) Yes (4) No (6) Studied related subject Have you studied fermentation and purification aspects of bioprocess technology earlier? (16) Yes (11) No Have you studied biochemical (mathematical equations) aspects of bioprocess technology in your earlier studies? (7) Yes (6) No (14) Partly 16

3 What do expect and other comments Learn about technical uses of living microorganisms or biochemistry in industry, as an engineer Liked background music. Hope study seems such fun all over the course. I hope I pass this... 5 credits To learn new interesting things about biotechnology basic knowledge and concept of bioprocess technology. Have a common view to use bioprocess technology in biomass refining. Not too deep or too detail now. Understanding of the process flow and equation et some specific biochemistry process I hope I pass How to optimize processes I'm hoping to learn more about bioprocesses in general Want to know modern techniques to design a bioprocess plant and applying learning outcomes for future thesis or research work Basic knowledge of bioprocess technology The mechanisms of microbial processes Very excited to be here! To have best possible tools for biomass refining Combination of biochemistry and technical chemistry Learn more about bioprocess technology To learn more about bioprocess I want to learn more from large scale production processes Knowledge about bioprocess technologys latest R&D To learn about different types of bioprocesses that may prove usegul to me in the future. I might even start a brewery some day :) This is a nice chat! Understand the basic concepts of Bioprocess technology and study the mathematical equations.

4 We discussed. Obligate aerobes Faultative anaerobes Obligate anaerobes Aerotolerant anaerobes Microaerophiles Lag phase Log Phase Stationary Phase Death Phase Logarithmic Scale Number of Bacteria Time 18

5 Fermentation Biochemical meaning - energy-generation process in which compounds act as both electron donors and terminal electron acceptors. Industrial microbiology meaning - any process for the production of product by the mass culture of a micro-organism. Under-aerobic conditions, reoxidation of reduced pyridine nucleotide occurs by electron transfer, via the cytochrome system, with oxygen acting as the terminal electron acceptor. Under anaerobic conditions, reduced pyridine nucleotide oxidation is coupled with the reduction of an organic compound, which is often a subsequent product of the catabolic pathway. Different microbial taxa are capable of reducing pyruvate to a wide range of end products. Thus, the term fermentation has been used in a strict biochemical sense to mean an energy-generation process in which organic compounds act as both electron donors and terminal electron acceptors. Image source -

6 The range of fermentation process There are five major groups of commercially important fermentations: Those that produce microbial cells (or biomass) as the product. Those that produce microbial enzymes Those that produce microbial metabolites. Those that produce recombinant products. Those that modify a compound which is added to the fermentation - the transformation Further reading - Peter F. Stanbury, Allan Whitaker, Stephen J. Hall, Principles of Fermentation Technology, second edition, Butterworth-Heinemann, pp

7 The component parts of a fermentation process (1) Formulation of media to be used in culturing the process organism during the development of the inoculums (2) Sterilization of the medium, fermenters and ancillary equipment. (3) Production of an active, pure culture in sufficient quantity to inoculate the production vessel. (4) Growth of the organism in the production fermenter under optimum conditions for product formation. (5) Extraction of the product and its purification. (6) Disposal of effluents produced by the process. 21 Stanbury et al., 1995, pp 9-10

8 Microbial Growth kinetics - Autocatalytic reaction: The rate of growth is directly related to cell concentration substrates + cells extracellular products + more cells S + X P + nx S: substrate concentration (g/l); X: cell mass concentration (g/l); P: product concentration (g/l); n: increased number of biomass. Net specific growth rate (1/time): t: the time µ net 1 X dx dt µ net = µ g k d μ net is net specific growth rate (h -1 ). The net specific growth is difference between gross specific growth rate, μ g (h -1 ) and rate of loss of cell mass due to cell death or endogenous metabolism (k d h -1 ) 22 Shuler and Kargi, 2002

9 Batch growth kinetics Yield coefficients: based on the amount of consumption of another material. Growth yield : ΔX Y X / S ΔS Product yield : ΔP Y P / S ΔS Growth yield based on consumption of Y X / O2 ΔX ΔO 2 oxygen : Yx/s = g/g glucose Yx/ O2 = g/g O 2 ΔS = ΔS assimilation into biomass +ΔSassimilation into an extracellular product 23 +ΔS growth energy+ ΔS maintenance energy Shuler and Kargi, 2002

10 Growth kinetic quantification Growth models are used to describe the cell growth system Unstructured model - fixed cell composition (balanced growth), cell population is treated as single component Structured Models - Variable cell composition (unbalanced growth), cell population is treated as a multi-component system Nonsegregated Models - Cells are treated as homogeneous Gernaey et al., Trends in Biotechnology 28, Segregated Models - cells are treated heterogeneous 24