Bài giảng Kỹ thuật phản ứng sinh học: Chương 3 Động học phản ứng tạo sinh khối, cung cấp cho người học những kiến thức như: Quá trình tạo sinh khối vi sinh vật; Kỹ thuật nuôi cây theo mẻ; Kỹ thuật nuôi cây theo mẻ có bổ sung cơ chất; Phương trình Monod và Động học tạo sinh khối vi sinh vật. Mời các bạn cùng tham khảo!
http://buihongquan.com Chương Động học phản ứng tạo sinh khối 3.1 Cá c khá i niệ m bả n 3.2 Quá trình tạ o sinh khó i vi sinh vạ t 3.3 Kỹ thuạ t nuoi cá y thêo mể 3.4 Kỹ thuạ t nuoi cá y thêo mể có bỏ sungcơ chá t 3.5 Phương trình Monod và Đọ ng họ c tạ o sinh khó i vi sinh vạ t 12/23/2018 Bioreaction engineering 152 http://buihongquan.com BIOLOGICAL REACTIONS •BIOREACTORS Lab Scale Bioreactor Industrial Scale Bioreactor 12/23/2018 Bioreaction engineering 153 http://buihongquan.com Fermentation Process 12/23/2018 Bioreaction engineering 154 http://buihongquan.com Major Functions of a Bioreactor 1) Provide operation free from contamination; 2) Maintain a specific temperature; 3) Provide adequate mixing and aeration; 4) Control the pH of the culture; 5) Allow monitoring and/or control of dissolved oxygen; 6) Allow feeding of nutrient solutions and reagents; 7) Provide access points for inoculation and sampling; 8) Minimize liquid loss from the vessel; 9) Facilitate the growth of a wide range of organisms Ref;(Allman A.R., 1999: Fermentation Microbiology and Biotechnology) 12/23/2018 Bioreaction engineering 155 http://buihongquan.com Biotechnological Processes Microorganisms In A Bioreactor Of Growing 1) Batch culture: microorganisms are inoculated into a fixed volume of medium and as growth takes place nutrients are consumed and products of growth (biomass, metabolites) accumulate 2) Semi-continuous: fed batch-gradual addition of concentrated nutrients so that the culture volume and product amount are increased (e.g industrial production of baker’s yeast); Perfusion-addition of medium to the culture and withdrawal of an equal volume of used cell-free medium (e.g animal cell cultivations) 3) Continuous: fresh medium is added to the bioreactor at the exponential phase of growth with a corresponding withdrawal of medium and cells Cells will grow at a constant rate under a constant condition.Bioreaction engineering 12/23/2018 156 http://buihongquan.com Biotechnological processes of growing microorganisms in a bioreactor 12/23/2018 Bioreaction engineering 157 http://buihongquan.com A Fermenter / Bioreactor And Its Parts by Genentech, Corporate Communication 12/23/2018 Bioreaction engineering 158 http://buihongquan.com Single System for Anchorage-Dependent and Suspension Cultures New Brunswick Scientific Company 12/23/2018 Bioreaction engineering 159 http://buihongquan.com 1500L-Scale Bioreactors (courtesy of Tanox ) 12/23/2018 Bioreaction engineering 160 http://buihongquan.com Batch Culture VS Continuous Culture Continuous systems: limited to single cell protein, ethanol productions, and some forms of waste-water treatment processes Batch cultivation: the dominant form of industrial usage due to its many advantages Ref;(Smith J.E, 1998: Biotechnology) 12/23/2018 Bioreaction engineering 161 http://buihongquan.com Advantages of Batch Culture VS Continuous Culture 1) Products may be required only in a small quantities at any given time 2) Market needs may be intermittent 3) Shelf-life of certain products is short 4) High product concentration is required in broth for optimizing downstream processes 5) Some metabolic products are produced only during the stationary phase of the growth cycle 6) Instability of some production strains require their regular renewal 7) Compared to continuous processes, the technical requirements for batch culture is much easier 12/23/2018 Bioreaction engineering 162 http://buihongquan.com Fermentation Technology What is it important to know the kinetics of the reaction in the fermenter? 12/23/2018 Bioreaction engineering 163 http://buihongquan.com Cell Growth Typical pattern of growth cycle during batch fermentation I II III Lag phase Acceleration phase Exponential (logarithmic) phase IV Deceleration phase V Stationary phase VI Accelerated death phase VII Exponential death phase VIII Survival phase 12/23/2018 Bioreaction engineering 164 http://buihongquan.com Cell Growth cont Lag Phase •Little increase in cell conc •Cell adjusting their new environment, synthesizing enzymes & ready to reproducing 12/23/2018 Exponential Growth Phase •Cell are dividing at max rate •Cell able to use the nutrients most efficiently Stationary Phase •Cell reach a minimum biological space (lack of 1@> nutrients limits cell growth) •Net growth = •Fermentation product produce Bioreaction engineering Death Phase •Decrease in live cell conc occur •Results of toxic byproduct 165 http://buihongquan.com Rate Laws Rate law for the cell growth rate of new cells, Cells + Substrate More Cells + Product The most commonly used expression is the Monod equation for exponential growth; rg Cc Where, rg cell _ growth _ rate( g / dm3 s) specific _ growth _ rate(s 1 ) Cc cell _ concentrat ion( g / dm3 ) 12/23/2018 Bioreaction engineering 166 http://buihongquan.com Rate Laws cont Specific cell growth rate can be expressed as, max Cs 1 ,s K s Cs Where, max a _ max_ specific _ growth _ reaction _ rate(s 1 ) K s the _ monod _ cons tan t ( g / dm3 ) Cs substrate(nutrient )concentrat ion( g / dm3 ) 12/23/2018 Bioreaction engineering 167 http://buihongquan.com Rate Laws cont Combine, rg Cc Will get, rg and max max C s Cc K s Cs max 1.3h 1 K s 2.2 X 10 5 mol / dm3 Cs , s 1 K s Cs Monod equation for bacterial cell growth rate Parameter value for the E.coli growth on glucose Ks is small for a numb of different bacteria in which case the rate law reduce to, rg max Cc 12/23/2018 Bioreaction engineering 168 ... •BIOREACTORS Lab Scale Bioreactor Industrial Scale Bioreactor 12/ 23/ 2018 Bioreaction engineering 1 53 http://buihongquan.com Fermentation Process 12/ 23/ 2018 Bioreaction engineering 154 http://buihongquan.com... 2) Semi-continuous: fed batch-gradual addition of concentrated nutrients so that the culture volume and product amount are increased (e.g industrial production of baker’s yeast); Perfusion-addition... Communication 12/ 23/ 2018 Bioreaction engineering 158 http://buihongquan.com Single System for Anchorage-Dependent and Suspension Cultures New Brunswick Scientific Company 12/ 23/ 2018 Bioreaction