Case study: biotechnological production of CoQ10 by fed-batch fermentation Coenzyme Q10 is a valuable lipidic product synthesized by several organisms. It’s an intracellular metabolite which plays a role in the electron transport chain. Synthesis is oxygen-dependent by R. sphaeroides, and reported yields are up to 770 mg/L (9 mg/g DCW) at 30 °C, controller agitation, pH and aeration in fed-batch culture after ~72 h. Carbon and nitrogen sources vary according to raw-material availability and alternative low-cost sources may be utilized. The product market is expected to grow to $1 billion by 2026 as it’s being widely used as a food and cosmetic supplement due to its bioactive properties. Let the overall bioreaction be: πΆ6 π»12 π6 + πΌπ2 + π½ππ»4 πΆπ → πΎπ + πΏπΆ59 π»90 π4 + ππΆπ2 + ππ»2 π + ππ»πΆπ Species G Glucos e O Oxygen N Ammoniu m chloride X Biomass P Coenzym e Q10 C Carbon dioxide W Water CO2 A Hydroge n chloride HCl Formula C6H12O6 O2 NH4Cl CH1.99O0.5N0.1 C59H90O4 Phase Solid Gas Solid Aqueous Solid Gas Aqueous 26.64 - 863.365 1? 36.46 1.49 - 50 insoluble 44 0.00197 7 1.7 Liquid . 18 1 MW Sp. Gr. 180.16 1.54 53.49 1.519 Tf Tb Solubilit y (water) 148 909 32.0 0.00142 9 -218 -183 0.007 337 383 720 0 100 - H2O 9 Bioreaction πΆ6 π»12 π6 + πΌπ2 + π½ππ»4 πΆπ → πΎπ + πΏπΆ59 π»90 π4 + ππΆπ2 + ππ»2 π + ππ»πΆπ π = πΆπ»1.99 π0.5 π0.19 π π = πΆ 0 0 1 59 1 π» 0 −4 1.99 90 0 π΄ π = −2 0 0.5 4 2 π 0 −1 0.19 0 0 [πΆπ ] [ 0 −1 0 0 0 π =2 πΌ 0 2 1 0 0 πΌ π½ π1 = 6 + (πΌ − π) 0 πΎ π2 = 12 1 0 ∗ πΏ = π3 = 6 + (2πΌ − 2π) π π4 = 0 0 ] π π5 = 0 1 [ ] [ π] Taking RQ = 2; 2α = ε, thus α = 0.5 y ε = 1: π1 = 5 π½ πΆ 0 1 59 0 0 π πΎ π» −4 1.99 90 2 1 2 = 12 π΄ π = 0 0.5 4 1 0 ∗ πΏ = π3 = 3 π π4 = 0 π −1 0.19 0 0 0 [πΆπ ] [−1 0 0 0 1] [ π] [ π5 = 0 ] πΆ6 π»12 π6 + 0.5π2 + 0.18ππ»4 πΆπ → 0.98π + 0.068πΆ59 π»90 π4 + 1πΆπ2 + 2.24π»2 π + 0.18π»πΆπ Hierarchical process synthesis LEVEL 1: DECISIONS ON BATCH vs CONTINUOUS - Technical information: Does any apparatus work in batch mode? Is the process sensitive to upsets & variations? Fed-batch mode suggested, sensitive to variations. - Production rate High or low production rate? Only few days production needed? Few days operational notice? Low production rate, process needs 3 days to complete. - Product lifetime One or two years or longer? Longer. - Value of product… Product value >> manufacturing cost? Yes. LEVEL 2: DECISIONS ON INPUT-OUTPUT STRUCTURE - - Raw materials – Impurities? If the impurities are inert, remove them after reaction, if they’re valuable – Non valuable. If the impurities are inert, present in large amounts, and can be easily separated, remove them before the reactor – Impurities in aqueous solution, inert or taken up for cell metabolism. If the impurities have boiling points lower than the reactants and products, and they’re also inert, recycle them (note: purge unit will be needed!!) – Reaction occurs at liquid state, well below species’ boiling point. If the impurities are also products from the reactor, place feed stream before the unit that will remove the impurities – biomass must be removed, fed-batch is proposed. - Product streams? Recycle unreacted reactants – OK… Recycle intermediate reactants (products) – No Recycle/remove azeotropes with reactants – No Remove (recover) the main product – OK Remove (recover) the valuable by-products – None Remove (as waste)/recycle by-products that are not valuable – OK. - Recycle? Purge Units? For <100% conversion of reactants and reaction in the gas phase. - - Recycle of gases will be necessary – Not necessary. (Check CO2, water) If impurities are present, purge units will be necessary – No. (Check CO2, water). For < 100% conversion and reaction in the liquid phase, Recycle of liquids (reactants) will be necessary – May be possible to recycle carbon source stream. If impurities are present, purge units will be necessary – YES Reversible by-products? Selectivity vs costs? EP2 = Product value – By-products value – Raw-material value Product value (standard): $450 USD/gram*(1000 gram/kg) – 0(no valuable by-products) – $0.6 USD/kg CS - $2.25 USD/kg NS… Approximately $450,000 USD/kg of product. Noting each batch takes around 72 h, reported scale-up volume of up to 150 L: 0.77 g/L*(150 L/3 days)*($450K/kg)*(300 days/year) = $5.2 Million/yr. mm LEVEL 3: DECISIONS ON RECYCLE STRUCTURE & REACTORS - - - Number of reactors? If more than one reactor is needed to get the desired product, more than one reactor will be needed if the conditions are very different 1 reactor? Number of recycle streams? Depends on the number of raw materials and conversion of all reactants… Oxygen comes from air; sugar may be reused (1 stream), find conversion from yield. Take biomass out (centrifuge). Need for compressor/pump? Air is fed at atmospheric pressure. Pump needed for recycle stream. Compressor for CO2 stream. - - Reactor type? Adiabatic or Isothermal? If temperature change is too high or low, heating/cooling will be needed – Isothermal (jacketed reactor). Reaction equilibrium or kinetics? Kinetically controlled or equilibrium reached? - ??? EP3 = EP2 – (reactor cost + pump cost + compressor + heat exchr). LEVEL 4: DECISIONS ON SEPARATION SYSTEMS - Vapour recovery and/or liquid recovery? – Rules If reactor stream is in liquid phase, use liquid recovery If reactor stream has 2 phases (separate the 2 phases first) – Liquid phase only Reactor stream is gas (vapour) phase: may need to condense CO2 How to locate & perform separation? EP4 = EP3 – (vapor recovery cost + liquid recovery cost) - Vapour recovery system (VS) – Location No vapour - Liquid recovery system (LS) Decisions on… - No distillation; other types of separations ARE possible. - Cell harvesting? Microfiltration/centrifugation? - Cell disruption: homogenization/bead milling/ultrasound - Cell debris removal: centrifugation/microfiltration. - Extraction by: ORGANIC SOLVENTS (Hexane). It’s not been reported though reversed micelle technology suitable. - Purification: SEC, liquid-liquid extraction, crystallization in vacuum dryer. Mixture analysis: ??? MASS BALANCES BY UNIT U01 + U02 = U11 + U12 U11 = U21 + U22 U21 + U03 = U31 U31 = U41 + U42 U41 + U04 = U51 U51 = U61 + U62 + U63 U61 + U05 = U71 U71 = U81 + U81 BY COMPONENT: REACTOR If the working volume is 2800 L, fed with media containing 50 g/L glucose and 4 g/L NH4Cl, and considering glucose comes as a solution 70%w/v, then the pure water volume would be 2600 L. Additionally, if bioreactor operates at 0.5 vair/vmed/min, that’d make 30 v/v/h. If reactor operates (2800 L/72 h = 38.83 L), then our air volume would be 30 La/Lm/h * 38.83 Lm = 1166.6 Lair/h. By the ideal gas law (1 mol = 22.4 L) and O2 in air is at 21%: 1166.6 Lair/h*(1 gmol/22.4 Lair)*0.21 Lo/Lair = 10.94 mol/h. Thus: UG01 = 10.8 mol/h UN01 = 2.91 mol/h Uo01 = 10.94 mol/h Uw01 = 2000 mol/h. The fixed conversion reactor given by substrate consumption is fixed to 0.9. UG11= UG01(1-0.9) = 0.1 UG01 = 1.08 mol/h UN11= UN01 – 0.18*(0.9 UG01) = 1.2 mol/h Uo12= Uo01 – 0.5*0.9 UG01 = 6.1 mol/h (leaves as gas) Uw11= Uw01+2.24*0.9 UG01 = 2021.8 mol/h UX11 = 0.98*0.9 UG01 = 9.6 mol/h UC12 = 0.9 UG01 = 9.7 mol/ h (leaves as gas) UH11 = 0.18*0.9 UG01 = 1.8 mol/h UP11 = 0.068*0.9 UG01 = 0.66 mol/h IN FIRST DIVIDER (Centrifuge) Mixture contains biomass (X), product (P), water (W), and waste glucose and ammonium chloride (G & N) and produced acid chloride (H, supposed to be neutralized during reactor operation). Also, cell water content is around 70%: Input: π11 = 9.6 πππ 0.66πππ πππ πππ πππ πππ π+ π + 2022 π + 1.08 πΊ + 1.16 π + 1.75 π» β β β β β β Output: π21 = 9.6 πππ πππ πππ π + 0.66 π + 22 π β β β π22 = 2000 πππ πππ πππ π + 1.08 πΊ + 1.16 π β β β IN FIRST MIXER At the first mixer a neutralization reaction occurs, so cell is disrupted. π03 is a solution with 0.25 L of H2SO4 (3%) + 0.4 L of NaOH (14%) are fed are mixed to U21 and heated to 90 °C. Salts are to be removed. π»2 ππ4 + 2ππππ» → ππ2 ππ4 + 2π»2 π Input: UH2SO403 = 0.08 mol/h UNaOH03 = 1.4 mol/h Uw03 = 35 mol/h U21 = 9.6 mol/h X + 0.66 mol/h P + 22 mol/h W Output: UNa2SO431 = 0.08 mol/h UNaOH31 =1.24 mol/h UX31 = 9.6 mol/h UP31 = 0.66 mol/h Uw31 = 58.4 mol/h IN CLARIFIER Assuming total fatty acid content in dry cells is about 10%. We’ll assume a fraction of water content boiled at previous step and crystals are left dry. Input: U31 = 69.9 mol h Output: UP41 = 0.66 mol/h UX41 = 1 mol/h (lipid crystals, biomass base) UX42 = 8.6 mol/h (as cell debris) UNa2SO442 = 0.08 mol/h UW42 = 58.4 mol/h UNaOH42 = 1 mol/h IN SOLVENTIZER This stage will assume all product mass is going to be dissolved (absorbed) by the organic solvent (hexane). 0.5 L/h is added = 3.8 mol/h. INPUT U41 = 0.66 mol/h P + 1 mol/h lipid crystals = 1.66 mol/h U04 = 3.8 mol/h Output: U51 = 5.46 mol/h IN VAPORIZER All solvent is vaporized and leaves as gas. Cell debris fatty crystals are removed, and we may consider some product leaves attached to debris. Input U51 = 5.46 mol/h Output UP61 = 0.59 mol/h UX61 =0.1 mol/h U62 = 3.8 mol/h UP63 = 0.07 mol/h UX63 = 0.9 mol/h PREPARATION FOR PURIFICATION Raw product stream U61 is diluted in a hexane/isopropanol mixture (10:2) as mobile phase for chromatography. Input UH05 = 2 mol/h UI05 = 0.69 mol/h U61 = 0.69 mol/h Output U71 = 3.38 mol/h CHROMATOGRAPHY UNIT Assume continuous chromatographer. All product is recovered? Assuming pure product stream: Input U71 = 3.38 mol/h Output UP81 = 0.59 mol/h UH81 = 0.026 mol/h UI81 = 0.005 mol/h U81 = 0.621 mol/h UH82 = 1.974 UI82 = 0.685 mol/h UX82 = 0.1 mol/h U82 = 2.759 mol/h %MASS BALANCE FOR GLUCOSE %GLOBAL BALANCE %Coefficients Y_G=-1 Y_N=-0.18 Y_O=-0.5 Y_X=0.98 Y_P=0.068 Y_C=1 Y_W=2.24 Y_A=0.18 ETA_G=0.95 ETA_S=1 Y2_OH=-2 Y2_S=-1 Y2_F=1 Y2_W=2 %SPLIT FRACTIONS Z1_G=1 Z1_N=1 Z1_A=1 Z1_X=1 Z1_P=1 Z1_O=0 Z1_W=0.01 Z2_X=0.1 Z2_P=0.95 Z2_W=1 Z2_F=1 Z2_OH=1 Z3_X=0.05 Z3_P=0.95 Z3_H=1 Z4_P=0.99 Z4_X=0.001 Z4_H=0.001 Z4_I=0.001 x1=0.5 x2=5 x3=6 %Across reactor: M01_G=0.05*M01 M11_G=M01_G+Y_G*ETA_G*M01_G M21_G=0 M22_G=Z1_G*M11_G %MASS BALANCE FOR NITROGEN SOURCE M01_N=0.004*M01 M11_N=M01_N+(Y_N)*(ETA_G)*M01_G M21_N=0 M22_N=Z1_N*M11_N %MASS BALANCE OXYGEN: M02_O=0.5*M01_G M12_O=M02_O+Y_O*ETA_G*M01_G M22_O=M12_O %MASS BALANCE CARBON DIOXIDE M12_C=Y_C*ETA_G*M01_G %MASS BALANCE HYDROCHLORIC ACID M11_A=Y_A*ETA_G*M01_G M22_A=Z1_A*M11_A M21_A=0 %MASS BALANCE BIOMASS M11_X=Y_X*ETA_G*M01_G M21_X=Z1_X*M11_X M22_X=(1-Z1_X)*M11_X M31_X=M21_X M41_X=Z2_X*M31_X M42_X=(1-Z2_X)*M31_X M51_X=M41_X M61_X=Z3*M51_X M63_X=(1-Z3_X)*M51_X M71_X=M61_X M81_X=Z4_X*M71_X M82_X=(1-Z4_X)*M71_X %MASS BALANCE PRODUCT M11_P=(Y_P)*(ETA_G)*M01_G M21_P=Z1_P*M11_P M22_P=(1-Z1_P)*M11_P M31_P=M21_P M41_P=Z2_P*M31_P M42_P=(1-Z2_P)*M31_P M51_P=M41_P M61_P=Z3*M51_P M63_P=(1-Z3_P)*M51_P M71_P=M61_P M81_P=Z4_P*M71_P M82_P=(1-Z4_P)*M71_P %MASS BALANCE SULFURIC ACID M03_S=x1 M31_S=(Y2_S)*(ETA_S)*M03_S %MASS BALANCE SODIUM HYDROXIDE M03_OH=18*x1 M31_OH=M03_OH+(Y2_OH)*(ETA_S)*(M03_S) M42_OH=Z2_OH*M31_OH M41_OH=(1-Z2_OH)*M31_OH %MASS BALANCE SODIUM SULPHATE M31_F=(Y2_F)*(ETA_S)*(M03_S) M42_F=M31_F %MASS BALANCE HEXANE M04_H=x2 %FEED TO EVAPORIZE, SOLVATIZER M51_H=Z3_H*M04_H M62_H=M51_H M05_H=x3 M71_H=M05_H M82_H=(1-Z4_H)*M71_H M81_H=Z4_H*M71_H %MASS BALANCE ISOPROPANOL M05_I=(1/6)*x3 M71_I=M05_I M82_I=(1 - Z4)*M71_I M81_I=Z4_I*M71_I %MASS BALANCE WATER M01_W=M01-M01_G-M01_N M11_W=M01_W+(Y_W)*(ETA_G)*(M01_G) M21_W=Z1_W*M11_W M22_W=(1-Z1_W)*M11_W M03_W=(100/97)*M03_S+(100/86)*M03_N M31_W=M03_W+(Y2_W)*(ETA_S)*(M03_S) M41_W=0 M42_W=(Z2_W)*M31_W %streams M01=M01_G+M01_N+M01_W M02=M02_O M11=M11_G+M11_N+M11_X+M11_P+M11_A+M11_W M12=M12_O+M12_C M21=M21_P+M21_X+M21_W M22=M22_G+M22_N+M22_A+M22_W M03=M03_S+M03_OH+M03_W M31=M31_OH+M31_F+M31_W+M31_P+M31_X M41=M41_P+M41_X M42=M42_X+M42_W+M42_OH+M42_F M04=M04_H M51=M51_P+M51_X+M51_H M61=M61_P+M61_X M63=M63_P+M63_X M63=M63_H M05=M05_H+M05_I M71=M71_X+M71_P+M71_H+M71_I M81=M81_P+M81_X+M81_H+M81_I M82=M82_P+M82_X+M82_H+M82_I μ01 μ02 μ03 μ04 μ05 μ11 μ12 μ21 k G O N X P C A W H S B F I Streams μ22 μ31 μ41 μ42 μ51 μ61 μ62 μ63 μ71 μ81 μ82 k G O N X P C A W H S B F I SUM 2013.71 0.00536324 0 0.00144509 0 0 0 0 0.99319167 0 0 0 0 0 1 μ01 μ02 36.48 10.94 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0.95942982 0 0 0 0.00219298 0 0.03837719 0 0 0 0 1 1 μ03 μ04 2.69 3.8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0.74349442 0 0 0 0 0 0 0 0.25650558 1 1 μ05 μ12 μ21 32.26 15.8 2036.14 0 0 0.00053042 0 0 0.38607595 0 0 0.00058935 0 0.29758215 0.0047148 0 0.02045877 0.00032414 0 0 0.61392405 0 0 0.00088403 0 0.68195908 0.99295726 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 μ11 Streams μ62 μ61 μ51 μ42 μ41 μ31 0.69 5.46 68.32 1.66 69.98 2004.04 0 0 0 0 0 0.00053891 0 0 0 0 0 0.00057883 0 0 0 0 0 0 0 0.13718205 0.60240964 0.12587822 0.18315018 0.14492754 0 0.12087912 0.85507246 0 0.00943127 0.39759036 0 0 0 0 0 0 0 0 0 0 0 0.00089819 0 0 0 0.85480094 0.99798407 0.83452415 0 0 0.6959707 0 0 0 0 0 0 0 0 0 0 0 0 0.01814988 0 0.01771935 0 0 0 0.00117096 0 0.00114318 0 0 0 0 0 0 1 1 1 1 1 1 μ22 μ82 μ81 μ71 μ63 2.759 0.621 3.38 0.97 3.8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.03624502 0 0.92783505 0.0295858 0 0 0.07216495 0.17455621 0.95008052 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0.59171598 0.04186795 0.71547662 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.20414201 0.00805153 0.24827836 0 1 1 1 1 1 E = I1 * R1 1/R1 = 1/Ra + 1/Rb1 E = I2 * R2 1/R2 = 1/Ra + 1/Rb2 Rb1 = 1 Rb2 = 10 E = 12
0
You can add this document to your study collection(s)
Sign in Available only to authorized usersYou can add this document to your saved list
Sign in Available only to authorized users(For complaints, use another form )