microbial and biocatalytic production of advanced ... · microbial and biocatalytic production of...
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PRODUCTIONbio
Bioproduction IP
Microbial and Biocatalytic Productionof Advanced Functional Polymers
Costas Kiparissides Department of Chemical Engineering, Aristotle University of
Thessaloniki, and Chemical Process Engineering Research Institute, Centre for Research and Technology Hellas
Thessaloniki, Greece
Biorefinica: International Symposium Biobased Products and Biorefineries,
Osnabruck, Germany, January 27-28, 2009
PRODUCTIONbio
Bioproduction IP
Bioproduction Objectives
• Development of an industrial R&D platform in sustainable productionof functional biopolymers , chemical building blocks and biosurfactants.
• Use of renewable agricultural sources (e.g., corn, wheat, sugar beets) and wastes as raw materials and biological processes (fermentation, biocatalysis).
• Development of novel biocatalysts (enzymes) for higher product efficiency, improved stability, reduction of the number of conversion steps and replacement of difficult syntheses by simpler processes.
• Application of advanced modeling, on-line monitoring and controlmethodologies to bioprocesses (Digital Bioprobuction).
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Bioproduction IP
Industries & SMEs - 11• KitoZyme SA (KitoZyme) – BELGIUM
• Procter & Gamble (P&G) – BELGIUM
• Tate and Lyle – FINLAND
• Artes Biotechnology GmbH (ARTES) – GERMANY
• FMC Biopolymer AS/Nova Matrix (FMC Biopolymer) – NORWAY
• Companhia Petroquímica do Barreiro S.A. (CPB) – PORTUGAL
• BIOMEDAL S.L. (BIOMEDAL) – SPAIN
• BIOPOLIS S.L. (BIOPOLIS) – SPAIN
• IMEnz Bioengineering BV (IMEnz) – THE NETHERLANDS
• Ciba Specialty Chemicals PLC (CIBA) – UK
• The Centre for Process Innovation (CPI) – UK
List of Partners
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Research Institutions - 6• Centre for Research and Technology Hellas / Chemical Process
Engineering Research Institute (CERTH/CPERI) – GREECE
• DWI an der RWTH Aachen (DWI/RWTH) – GERMANY
• Instituto di Ricerca Protos (PROTOS) – ITALY
• Consejo Superior De Investigaciones Científicas -Centro De Investigaciones Biológicas (CSIC-CIB) – SPAIN
• Instituto de Ciencia e Tecnologia de Polimeros (ICTPOL) – PORTUGAL
• Agrotechnology and Food Innovations (A&F) – THE NETHERLANDS
List of Partners (cont’d)
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Universities - 8• Institute of Chemical Technology Prague (ICT Prague) – CZECH REPUBLIC
• Technical University of Denmark (DTU) – DENMARK
• Université Louis Pasteur (ULP) – FRANCE
• University of Stuttgart (UST) – GERMANY
• Universidad del Pais Vasco (UPV/EHU) – SPAIN
• Royal Institute of Technology (Kungliga Tekniska Högskolan) (KTH) –SWEDEN
• University of Newcastle, Newcastle upon Tyne (UNEW) – UK
• University of Liege, (ULg) – BELGIUM
List of Partners (cont’d)
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Bioproduction IP
European Dimension of Partnership
CERTH/CPERI
BiomedalBiomedal
IMEnzBioengineering
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Bioproduction IP
From Microorgnisms to Functional Biomaterials
• Epimerases• Alginate C-5 epimerases• Proteases• Lipases & esterases• C. antarctica lipase B• PHA depolymerases, hydrolases • C-LYTAG-tagged PHA
depolymerases• Immobilised-encapsulated C-
LYTAG-tagged PHA depolymerases
• Chitinases, chitin deacetylases• Glycerol-dehydratases• Alcohol dehydrogenases,
carboxydrate oxidases and laccases
WP 2
• PLA• PHAs
Particles coated with BioF-protein fusionsAmorphous & semi-crystalline PHAPHA with unsaturated monomers and with monomers with carboxylic groupsPHB, P(3HB-co-3HV)Polyhydroxypropionate
• AlginatesAlginate biopolymers with tailored functionalityAlginate based wound care formats
• Chitin-glucan-chitosan biopolymers• Polyuronic acids• Polypeptides & proteins• Polycaprolactones• Antimicrobial, adhesive, repellent
FUNCTIONAL BIOPOLYMERSFUNCTIONAL BIOPOLYMERS
• Hansenula yeast strains (Staphylococcus, Arxula, Sordaria)
• Hansenula Polymorpha • E-coli• Ralstonia eutropha• Pseudomonas fluorescens mutants-
GK13• Pseudomonas & Rhodococcus species• Pseudomonas putida KT2442• Bacterial plasmid vectors• Bacillus, Lactococcus, Lactobacillus• Streptomyces exfoliatus &
hygroscopius• Streptomyces lavendulae • Actinoplanes utahensis• Candida antarctica
ENZYMESENZYMES--BIOCATALYSTSBIOCATALYSTS
STARTING MATERIALSSTARTING MATERIALS•Fungal biomass•Fructose, surcose,
lactose•Glucose/methanol•Hexoses and
pentoses•Glucerol, corn step,
molasses, oils•Recycled paper
sludge
MICROORGANISMSMICROORGANISMS--NEW STRAINSNEW STRAINS
WP 1
WP 3,5
BUILDING BLOCKSBUILDING BLOCKS• Alginate substrates• Hydroxy acid-lactic acid
(succinic acid, butanediol, pentaerythritol)
• (R)-3-hydroxyalckanoic acids• Carbohydrate-based building
blocks: homo- and hetero-monomers for polyester and polyamide synthesis (dehydrohexitols)
WP 4
BIOSURFACTANTSBIOSURFACTANTS
• Sugar Fatty Acid Esters (SFAEs) (peptide surfactants)
• Functional cross-linked polysaccharides
• Epimerases• Alginate C-5 epimerases• Proteases• Lipases & esterases• C. antarctica lipase B• PHA depolymerases, hydrolases • C-LYTAG-tagged PHA
depolymerases• Immobilised-encapsulated C-
LYTAG-tagged PHA depolymerases
• Chitinases, chitin deacetylases• Glycerol-dehydratases• Alcohol dehydrogenases,
carboxydrate oxidases and laccases
WP 2WP 2
• PLA• PHAs
Particles coated with BioF-protein fusionsAmorphous & semi-crystalline PHAPHA with unsaturated monomers and with monomers with carboxylic groupsPHB, P(3HB-co-3HV)Polyhydroxypropionate
• AlginatesAlginate biopolymers with tailored functionalityAlginate based wound care formats
• Chitin-glucan-chitosan biopolymers• Polyuronic acids• Polypeptides & proteins• Polycaprolactones• Antimicrobial, adhesive, repellent
FUNCTIONAL BIOPOLYMERSFUNCTIONAL BIOPOLYMERS
• PLA• PHAs
Particles coated with BioF-protein fusionsAmorphous & semi-crystalline PHAPHA with unsaturated monomers and with monomers with carboxylic groupsPHB, P(3HB-co-3HV)Polyhydroxypropionate
• AlginatesAlginate biopolymers with tailored functionalityAlginate based wound care formats
• Chitin-glucan-chitosan biopolymers• Polyuronic acids• Polypeptides & proteins• Polycaprolactones• Antimicrobial, adhesive, repellent
• PLA• PHAs
Particles coated with BioF-protein fusionsAmorphous & semi-crystalline PHAPHA with unsaturated monomers and with monomers with carboxylic groupsPHB, P(3HB-co-3HV)Polyhydroxypropionate
• AlginatesAlginate biopolymers with tailored functionalityAlginate based wound care formats
• Chitin-glucan-chitosan biopolymers• Polyuronic acids• Polypeptides & proteins• Polycaprolactones• Antimicrobial, adhesive, repellent
FUNCTIONAL BIOPOLYMERSFUNCTIONAL BIOPOLYMERSFUNCTIONAL BIOPOLYMERSFUNCTIONAL BIOPOLYMERS
• Hansenula yeast strains (Staphylococcus, Arxula, Sordaria)
• Hansenula Polymorpha • E-coli• Ralstonia eutropha• Pseudomonas fluorescens mutants-
GK13• Pseudomonas & Rhodococcus species• Pseudomonas putida KT2442• Bacterial plasmid vectors• Bacillus, Lactococcus, Lactobacillus• Streptomyces exfoliatus &
hygroscopius• Streptomyces lavendulae • Actinoplanes utahensis• Candida antarctica
ENZYMESENZYMES--BIOCATALYSTSBIOCATALYSTSENZYMESENZYMES--BIOCATALYSTSBIOCATALYSTS
STARTING MATERIALSSTARTING MATERIALSSTARTING MATERIALSSTARTING MATERIALS•Fungal biomass•Fructose, surcose,
lactose•Glucose/methanol•Hexoses and
pentoses•Glucerol, corn step,
molasses, oils•Recycled paper
sludge
MICROORGANISMSMICROORGANISMS--NEW STRAINSNEW STRAINSMICROORGANISMSMICROORGANISMS--NEW STRAINSNEW STRAINS
WP 1
WP 3,5
BUILDING BLOCKSBUILDING BLOCKSBUILDING BLOCKSBUILDING BLOCKS• Alginate substrates• Hydroxy acid-lactic acid
(succinic acid, butanediol, pentaerythritol)
• (R)-3-hydroxyalckanoic acids• Carbohydrate-based building
blocks: homo- and hetero-monomers for polyester and polyamide synthesis (dehydrohexitols)
WP 4
BIOSURFACTANTSBIOSURFACTANTSBIOSURFACTANTSBIOSURFACTANTS
• Sugar Fatty Acid Esters (SFAEs) (peptide surfactants)
• Functional cross-linked polysaccharides
PRODUCTIONbio
Bioproduction IP
Microorganisms-Biocatalysts
ObjectivesSelection of high yield microorganisms and enzymesMutation of bacteria strains for improved productivity of new compounds and/or enzyme generation with improved propertiesImmobilization of enzymes and microorganisms for increased operational stability, catalytic activity and efficient product separation/purificationAlternative Media of high compatibility with substrates and product for maximum enzymic reaction routesProduction of Biocatalysts
Microorganisms & Enzyme libraries
Selection
Modification
Purification
TestingTechnologies
Recombinant bacteria, Enzymes, Vectors, Gene expression
techniques
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PRODUCTIONbio
Bioproduction IP
Production, purification and characterization of prototype P(3HO) depolymerase from P. fluorescens GK13Production
-1
-0,5
0
0,5
0 30 60 90Time (h)
Log
(A60
0)
1
2
34 5
Cel
lgro
wth
(Log
A60
0 nm
)
Culture time (h)
Growth assessment
Biostat A Fermentor
P(3HO) depolymerase activity assay
SDS-PAGE analysis
25
5037
15
75
1 2 3 4 5kDa
1 2 3 4 5•Step 1: Hydrophobic interaction chromatographyThe enzyme was adsorbed on Accurel MP1000 andeluted by 80% (v/v) isopropanol•Step 2: Size-exclusion chromatographySephacryl S-200 (30 x 1.5 cm) equilibrated in 50 mMglycine-NaOH (pH 9.5) 0.15 M KCl in an ÄKTA equipment
Purification
1. MW Markers2. Coomassie Blue stain3. Silver stain
25
5037
75
150kDa
15
25
5037
75
150
15 1 2 3
2 mg of pure enzyme was obtained from 1 liter of
fermentation broth
Production of Enzymes
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Bioproduction IP
Extracellular and Intracellular Production of Lipase from Thermus Thermophilus
Production of Enzymes
0
0.5
1
1.5
2
2.5
3
3.5
4
0 20 40 60 80 100
Time (h)
O.D
. 600
nm
0.8
1
1.2
1.4
1.6
1.8
2
Bio
mas
s (g
/l cu
lture
)
O.D. 600 nmBiomass
0
50100
150200
250
300350
400450
500
0 20 40 60 80 100Time (h)
Intra
cellu
lar A
ctiv
ity U
/lt
0
2
4
6
8
10
12
14
16
Extra
cellu
lar A
ctiv
ity U
/lt c
ultu
re
IntracellularExtracellular
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PRODUCTIONbio
Bioproduction IP
Molecular Modelling
Force Field Description (Potential Energy Function)
Thermodynamic Properties & Parameters
Enzyme Activity
Enzyme Selectivity
Free-Energy Profiles
Objectives• Determination of information concerning
structural and dynamic properties of biomolecules.
• Prediction of enzyme’s selectivity and substrate specificity.
• Assessment of theoretical tools as replacement of costly and time consuming experiments.
MD Software Tools•ABINIT (Density functional
theory)•AMBER (Molecular Mechanics)•CASTEP (ab-initio)•Car-Parrinello MD (Density
functional theory)•CHARMM (Molecular
Mechanics)
Enzyme Activity/Selectivity
PRODUCTIONbio
Bioproduction IP
Enzyme Immobilization Strategies
Improving catalyst efficiency, stability and recovery by immobilization.
Enzyme
S
P
S
P
SP
S P
S
P
S
PMonolithic reactor
Affinity binding tomulti-well plate
Entrapment within polymer, scaffold engineering
Encapsulation in micro/nano particles
Encapsulation/ immobilization in magnetic particle
S
P
N S
Covalent attachment on activated supports
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PRODUCTIONbio
Bioproduction IP
H2O
EnzymeSP
EnzymeS
PH2O
Organic
Organic
EnzymeS
P
Enzymes in Non-conventional Media
H2O
EnzymeS
ºCDeamidationPeptide hydrolysisCysteindecomposition
● Solvent property screening tools.
● Atomistic models to predict enzyme and substrate stabilityin new solvent environment (composition, pH, ionic strength, temperature, etc.).
● Other solvent aspects (mass transfer limitations, surface tension, toxicity, flammability, waste disposal, cost, etc.).
Medium engineering
Improving catalyst efficiency and stability by modifying its molecular environment.
Organic, reversed micelles, nanoemulsions.
S
PEnzyme
Enzyme instability/poor performance in aqueous media.
PRODUCTIONbio
Bioproduction IP
Production & Separation Systems
ObjectivesCost effective in-vivo production, separation and purification of biopolymers.
In-vitro or in-vivo production of intermediates from renewable sources.
Emphasis on process intensification, scaling-up, optimization of the production procedure and product end-use properties
Specifications of Bioproducts
Microorganisms & Biocatalysts
Process Development
Product Characterization
SeparationProcess scale-up
Strategies for optimal and economically efficient production
of bioproducts with desired properties
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PRODUCTIONbio
Bioproduction IP
Optimization of fermentation conditions for production of intermediates or end products.
Validation of nutrient sources.
Improved recombinant strains for PHA production and other products
Microbial Polymer Production
Optimization of PHA downstream polymer separation
• Bioreactor configuration• Feeding regimes• Process integration
PRODUCTIONbio
Bioproduction IP
PHA granule
Polymerases PhasinsDepolymerases
PHA
Regulators
Phospholipidmonolayer
0.5 μ
Pseudomonas Putida Producing PHA Granules
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PRODUCTIONbio
Bioproduction IP
End-use Properties `̀̀
Nutrients-Substrates
NutrientsSubstrates
Raw Materials
Bioreactor
Preculture
Cell Population
Single Cell
PHB Polymer
Applications
Bacteria Stock
Production Process-Flowchart
Extraction Techniques
PRODUCTIONbio
Bioproduction IP
Production of chiral hydroxyalkanoic acids from PHA
OH
O
CH2CH C
(CH2)5
OH
PHA
metabolism
PHA
PhaZ
In vitro
In vivo
Building Blocks
10
PRODUCTIONbio
Bioproduction IP
Recycled Paper Sludge conversion process
RPS(raw material)
BioproductEthanol
orLactic Acid
SSF(Enzymes + Microorganism)
Fermentation on SHF(Microorganism)
Saccharification(Enzymes)
Hydrolysis and downstream fermentation
Enzymatic hydrolysis of Cellulose + XylanFermentation of C5 (xylose) and C6 (glucose)
sugars
SHF, Separate Hydrolysis and Fermentation
SSF, Simultaneous Saccharification and (co-)Fermentation
Production of Lactic Acid
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Bioproduction IP
Advanced Functional Biomaterials
ObjectivesAdvanced functional biopolymers with specific properties for selected applications
Production of biosurfactants-SFAEs
Raw Materials
Synthesis Routes
Product Characterization
SeparationCommercial application screening
Advanced applications
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Bioproduction IP
ObjectivesSFAE that can be used as emulsifiers & surfactants
Tailored properties via variation of hydrophilic moieties
(carbohydrates, polysaccharides, ..) and hydrophobic chains
Acceptable colour/odour profiles for use in consumer
products
Sugar Fatty Acid Esters
PRODUCTIONbio
Bioproduction IP
Objectives Development of processes to produce novel lactic acid based copolymers with improved properties utilising biobased raw materials generated in the projectTesting and characterisation of the produced materialsModeling/simulation of PLA formation
Novel functional copolymers containing lactic acid
Improved properties compared to standard PLAComparable properties with traditional plastics for e.g. packaging applicationsMaterials with new properties for novel applications
Lactic Acid Based Copolymers
12
PRODUCTIONbio
Bioproduction IP
The main goals in the alginate part of the project are:• Make alginate based products for wound care applications and evaluate
the release of bioactive alginates and response to cellular biomarkers relevant to wound healing
• Production of alginate substrates by fermentation with available alginate over-producing Pseudomonas fluorescens strains.
• Find new mannuronan C-5 epimerases with tailored functionality by high throughput screening of an epimerase library generated by gene shuffling and error prone PCR
• Generation of yeast and bacterial strains that efficiently produces natural or engineered mannuronan C-5 epimerases in amounts sufficient to enable industrial epimerase production
• Develop an efficient and scalable fermentation and purification process for production of epimerases. Test novel reactor technology and “model assisted”optimization of the epimerase production in high cell density fermentations
• Produce test quantities of epimerases and use these for in vitroepimerization of alginate substrates to yield alginates possessing bioactivity
Alginate Based ProductsAlginate Based Products
PRODUCTIONbio
Bioproduction IP
ObjectivesIdentify new functionalities to be added to fungal biopolymers
Select chemical, enzymatic or blend modifications routes that follow the “non-polluting” process: industrial viability, vegetal based ingredients, avoid organic solvents, single step process.
Three functionalities were selected according to marketneeds:Water-soluble chitosanHydrophobic chitosanProcessable chitosan
Fungal Biopolymers
13
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Bioproduction IP
Microbial Production Microbial Production of PHAsof PHAs
PRODUCTIONbio
Bioproduction IP
• Microbial Production of PHAsDevelopment of high productivity processes for 3HB homo-polymers and co-polymers with tailored molecular/mechanical properties from wild and modified strains using as carbon sources renewable and waste materialsDevelopment and assessment of strategies for product separation/purification
• Digital BioprocessesDevelopment of integrated metabolic/polymerization modelsAlgorithms for on-line adaptive metabolic flux analysis for biological systems with dynamic metabolic networksDevelopment of segregated population models for microbial cultures combined with multi-objective optimisation algorithmsScaling-up of selected bioprocesses
Production of Biopolymers
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Bioproduction IP
•Pure substrates– Glycerol– Lactose– Sucrose– Octanoic acid
•Wastes/Surplus– Glycerol from
Biodiesel– Fermented
molasses– Cheese Whey
Raw Materials
•mcl-PHAs–P(3HHx)–Other
•scl- PHAs–PHB–P(3HB-co-3HV)–P(3HB-co-4HB)
Products
•Genetically modified– E.coli– P. putida KTfadB
•Wild Strains-P. putida KT2442-C. necator DSM545-H. Meditarranei-A. latus
•Mixed Cultures
Microorganisms
Microrganisms/Raw Materials/Products
PRODUCTIONbio
Bioproduction IP
Polyhydroxyalkanoates (PHAs)
• Polyhydroxyalkanoates (PHAs) are completely biodegradable polyesters of hydroxyalkanoatesthat are synthesized by many bacteria. The molecular weight of these polymers is in the range of 200,000 – 3,000,000 Da and they are accumulated in the cells in the form of discrete granules as a carbon and energy storagematerial.
• Polyhydroxybutyrate (PHB) was the first PHA to be discovered and is also the most widely studied and best characterized. It has mechanical properties very similar to conventional plastics, like propylene.
O
R O
100-30000n
O
O
n
15
PRODUCTIONbio
Bioproduction IP
FERMENTATIONRECOVERY
PURIFICATION
PRODUCT CHARACTERIZATION
PHA PRODUCTION
CULTURE MEDIUMCARBON SOURCEPs. putida KT2442
• Operation mode: continuous, fed-batch
• Culture medium• Limiting nutrient/nutrients: • C limitation/C/N limitation• Ambient variables: • Oxygen concentration, temperature• Fermentation time
• Disruption method: mechanicallysis, solvent extraction
• Solvent extraction: type of solvent, length, temperature
• Precipation method:Liquid/liquid, temperature
• Composition• Chain length distribution• Mechanical properties• Thermal properties
YieldProductivity Yield
Productivity
CostMonitoring
Research Objectives
PRODUCTIONbio
Bioproduction IP
Tailor-made PHAs by fermentation technology:The variability of bacterial PHAs produced by fermentation is exThe variability of bacterial PHAs produced by fermentation is extraordinary traordinary large (150 different monomers). large (150 different monomers).
PHA production processes:
• Single, continuous or fed-batch mode or in two-stage fed-batch mode with usual productivities ranging between 0.5 and 5 g PHA/L•h depending on strain and specifications of the productive procedure.
• Oxygen transfer rate becomes limiting at high cell densities and special reactor configurations are required.
4.9498.7111.7PHBA. latus
4.6141194PHBRecombinant E. coli
PHB
mcl-PHA
Product
3.14232281C. necator
1.9072141 P. putidaKT2442
Overall productivityg/L·h
PHA concentrationg/L
Cell concentrationg/L
Strain
Tailor-made PHAs
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PRODUCTIONbio
Bioproduction IP
P(3HB-co-3HV) copolymers – Microstructure Analysis
Batch experiments with alternated pulses of acetate and propionate and mixtures of acetate and propionate were performed.
• A copolymer P(3HB-co-3HV) was obtained and the 3HV fraction ranged from 34% to 78%, depending on the type and frequency of the substrate supplied.
• Monomers of 3HB produced with acetate pulses while production of 3HV was almost constant, the opposite was observed with propionate pulses.
• SEC analysis showed chromatograms with unimodal behaviour- copolymer;• The molecular weights were in the range 0.4-1.6×106;• One peak of Tg and Tm for the P(HB/HV) analysed ⇒ true copolymers obtained; • Tm between 88.5ºC and 93.8ºC and Tg between -14.3ºC and -5.4ºC which are in
accordance with the range of the HV proportion.
PHAsPHAs--Mixed culturesMixed cultures
PRODUCTIONbio
Bioproduction IP6 8 10 12 14 16 18 20
1.0x105
1.0x106
2
3
4
5
Mol
ecul
ar W
eigh
t (g/
mol
)
C/N ratio (g/g)
Mw
Mn
PDI
Pol
ydis
pers
ity In
dex
6 8 10 12 14 16 18 200.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
20
25
30
35
40
45
50
55
PHB
Conc
entra
tion
(g/l)
C/N ratio (g/g)
PHB Concentration (g/l) PHB Content (% g/g)
% P
HB
Cont
ent (
g/g
DCW
)
Same initial sucrose concentration (20 g/l) and different ammonium sulphate initial loadings (from 1 to 3 g/l).
Cultivation up to the stationary phase.
Molecular Weights
Molecular WeightDistributions
PHB Production
PHB-Medium CompositionStudy of the influence of the initial C/N ratio on the PHB production by Alcaligenes Latus
Batch Experiments
3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.50.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
Wf/[
dlog
MW
]
Log[MW]
C/N = 20 C/N = 13.3 C/N = 10 C/N = 8 C/N = 6.6
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PRODUCTIONbio
Bioproduction IP
Molecular PropertiesMw = 1,073,000 DaMn = 373,000 DaPD = 2.87Thermal PropertiesDegree of Crystallinity = 66%Tm = 176 oC
0 2 4 6 8 100.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
O.D
. @ 6
00 n
m
Time (h)
Optical Density Dry Cell Weight
DCW
(g/l)
0 2 4 6 8 10
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
0
5
10
15
20
25
30
35
40
45
50
PHB
Conc
entra
tion
(g/l)
Time (h)
PHB Concentration (g/l) PHB Content (% g/g)
% P
HB C
onte
nt (g
/g D
CW)
0 2 4 6 8 10
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
10.5
11.0
11.5
12.0
12.5
Amm
oniu
m C
once
ntra
tion
(g/l)
Time (h)
Phosphorous Ammonium Ph
osph
orou
s C
once
ntra
tion
(g/l)
Growth Curve
Nutrients Consumption
PHB Production
PHB-Kinetic StudiesMicrobial PHB production by Alcaligenes Latus in a 2 lt. Flask
PRODUCTIONbio
Bioproduction IP
0 5 10 15 20 25 30 35 40 450
10
20
30
40
50
60
70
80 PHB Content PHB Concentration Residual Biomass Concentration
Cultivation Time (h)
PHB
Con
tent
% (g
/g D
CW
)
0
1
2
3
4
5
6
7
8
9
10
PHB
Con
cent
ratio
n (g
/l) &
Res
idua
l Bio
mas
s C
once
ntra
tion
(g/l)
0 5 10 15 20 25 30 35 40 450
1
2
3
4
5
6
7
8
9
10
11
12
Dry Cell Weight Phosphates Conc. (NH4)2SO4 Conc.
Cultivation Time (h)
Dry
Cel
l Wei
ght (
g/l)
&Ph
osph
ates
Con
cent
ratio
n (g
/l)
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
(NH
4) 2SO
4 Con
cent
ratio
n (g
/l)
0 5 10 15 20 25 30 35 40 450
4
8
12
16
20
24
28
32
36
40
44
Optical Density Sucrose Concentration
Cultivation Time [h]
Opt
ical
Den
sity
@ 6
00 n
m
0
2
4
6
8
10
12
14
16
18
20
Sucr
ose
Con
cent
ratio
n (g
/l)
Molecular PropertiesMw = 436,300 DaMn = 199,100 DaPD = 2.19Thermal PropertiesDegree of Crystallinity = 63.24%Tm = 175.71 oC
Nutrients Consumption
PHB Production 80% wt. of DCW
PHB Kinetic Studies - Fed-BatchMicrobial PHB production by A. Latus in a 2 lt. Flask Fed-Batch
Substrate feeding
Substrate feeding
Substrate feeding
18
PRODUCTIONbio
Bioproduction IP2,210,0000.7748.0537.01
745,0000.5129.7015.00
595,8000.5428.3015.40
2,576,0000.7920.2016.10
860,0000.5037.5818.88
1,213,0000.6136.6722.37
1,576,1000.6638.1025.30
365,300
177,000
1,710,000
Molecular Weight of Recovered Polymer (g/mol)
0.45
0.41
0.63
Efficiency of the Recovery Method
32.8814.73
31.4613.03
11.687.35
PHB Content Determined by GC-MS/FT-IR Analysis (%)
Content of Precipitated PHB (%)
• Fermentation of A. latus in flasks and bioreactors
• Recovery Method: Cell disruption with sonication-CHCl3-based PHB extraction
• MW is the weight average molecular weight and [EF] the extraction efficiency ratio 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85
1x105
2x105
4x105
6x105
8x1051x106
2x106
4x106
MW = 5.970x106*[EF] - 2.305x106
R2 = 0.9584
Experimental Data Linear Fit
Mol
ecul
ar W
eigh
t (g/
mol
)
Extraction Efficiency
Study of the efficiency of the product recovery method depending on polymer Mw
PHB Processing
PRODUCTIONbio
Bioproduction IP
(a)(b)
(a)
3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.50.0
0.2
0.4
0.6
0.8
1.0
Wf/[
dlog
MW
]
Log[MW]
(a)(b)
(c)
(a) Sonication:40% amplitude 30 minMw = 1.8·106
(b) Sonication:50% amplitude 30 minMw = 1.2·106
(d) Reflux:65 oC 20 hrMw = 2.0·106
(e) Reflux:65 oC 40 hrMw = 1.0·106
(c) Sonication:50% amplitude 40 minMw = 0.5·106
(a)(b)
(c)
(d)
(a)(b)
(c)
(d)
(e)
Effect of the product recovery method on the polymer MWD
PHB-Downstream Processing
19
PRODUCTIONbio
Bioproduction IP
Digital BioprocessesDigital Bioprocesses
Model Developments Hardware Sensors
Software Sensors
1800,0 1700 1600 1500 1400 1300 1200 1100 1000,0Wavenumber, cm-1
A
z-v
z-v
OutputsNew Inputs
Optimization & Control
Model Developments Hardware Sensors
Software Sensors
1800,0 1700 1600 1500 1400 1300 1200 1100 1000,0Wavenumber, cm-1
A
1800,0 1700 1600 1500 1400 1300 1200 1100 1000,0Wavenumber, cm-1
A
z-v
z-v
OutputsNew Inputs
Optimization & Control
PRODUCTIONbio
Bioproduction IP
Multi-Scale Modeling Framework
MetabolicModels
• Unstructured• Structured• MFA
• Moment Methods• Distribution Methods
Reactor Models
PopulationModels
Polymerization Models
• Population Ensemble• Cell Ensemble• PBEs
• Ideal Mixing• Multizonal• CFD/Multizonal• Full CFD
Time Scale
Length Scale
PolymerizationModelling
PolymerizationModelling
Metabolic ModellingMetabolic Modelling
Population Modeling
Population Modeling
ReactorModelingReactor
Modeling
Time Scale
Length Scale
PolymerizationModelling
PolymerizationModelling
Metabolic ModellingMetabolic Modelling
Population Modeling
Population Modeling
ReactorModelingReactor
Modeling
Initiation
(Monomer Unit) (Synthase Dimer)
+ +(Coenzyme A)
Propagation
+
(Active [n]mer)
(Active [n+1]mer)
Coenzyme A
Chain Transferto Water H2O
Depolymerization
(Depolymerase)
(Inactive [n]mer)
(Inactive Monomer)
+
+
(Active Monomer)
Synthase Dimer
(Inactive [n+1]mer)
H2O
Depolymerase
Initiation
(Monomer Unit) (Synthase Dimer)
+ +(Coenzyme A)
Propagation
+
(Active [n]mer)
(Active [n+1]mer)
Coenzyme A
Chain Transferto Water H2O
Depolymerization
(Depolymerase)
(Inactive [n]mer)
(Inactive Monomer)
+
+
(Active Monomer)
Synthase Dimer
(Inactive [n+1]mer)
H2O
Depolymerase
P(3HB)n
Substrate
AcCoA
Ac-AcCoA
3-HB
Biomass
3-HBCoA
KrebsCycle
KrebsCycleCO2
O2NADHATP
Nitrogen
ATP
PhaA
PhaB
PhaC
PhaZ
Entner-Doudoroff Pathway
P(3HB)nP(3HB)n
SubstrateSubstrate
AcCoAAcCoA
Ac-AcCoAAc-AcCoA
3-HB3-HB
BiomassBiomass
3-HBCoA3-HBCoA
KrebsCycle
KrebsCycleCO2CO2
O2O2NADHNADHATPATP
NitrogenNitrogen
ATPATP
PhaA
PhaB
PhaC
PhaZ
Entner-Doudoroff Pathway
20
PRODUCTIONbio
Bioproduction IP
Reactor Models
PopulationModels
• Population Ensemble• Cell Ensemble• PBEs
• Ideal Mixing• Multizonal• CFD/Multizonal• Full CFD
•••Nutrients•••Substrates
•••Substrates•••Nutrients
•••Nutrients•••Substrates
•••Substrates•••Nutrients
MetabolicModels
• Unstructured• Structured• MFA
• Moment Methods• Distribution Methods
Polymerization Models
Time Scale
Length Scale
PolymerizationModelling
PolymerizationModelling
Metabolic ModellingMetabolic Modelling
Population Modeling
Population Modeling
ReactorModelingReactor
Modeling
Time Scale
Length Scale
PolymerizationModelling
PolymerizationModelling
Metabolic ModellingMetabolic Modelling
Population Modeling
Population Modeling
ReactorModelingReactor
Modeling
Multi-Scale Modeling Framework
PRODUCTIONbio
Bioproduction IP
Cell-Level: Metabolic Flux AnalysisComplete metabolic pathway of biomass growth and PHB accumulation in A. latus
“Bacteria Fermentation Culture for Synthesis of PHA Biopolymers as
Intracellular Product”Sucrose
glucose fructose
G6P
F6P
GAP
PEP
PYR
AcCoA
ICT
KG
OAA
SUC
AcAcCoA HBCoA PHB
Biomass
CO2,int CO2,ext
FADH 2 ATP
NADH 3 ATP
ATP energyNADH
ATP
ATP
ATP
ATP
NADHCO2
CO2
NADH
NADHCO2
NADHATP
CO2
NADHFADH
NADH
AcCoA
Jsuc1 Jsuc2
Jglu
Jg6p
Jgap
Jpep
Jpyr
Jacc Jaca Jhbc
Jfru
Joaa
Jict
Jkg
Jsuc
Jbio
Jco2
Jatp
Jnad
Jfad
Jppc
Jglx
Jf6p
Metabolism of sucrose towards the accumulation of PHB through Glucolysis as energy carbon storage and biomass growth through Krebs Cycle
The PHB production rate and the biomass growth rate are functions of sucrose diffusion from the culture medium through the cell membrane and its assimilation rate inside the cell.
Monomer unit
Metabolic Flux Analysis reveals that the PHB production rate is most sensitive to the manipulation of the F6P flux.
21
PRODUCTIONbio
Bioproduction IP
Intracellular PHB Accumulation in A. Latus
“Bacteria Fermentation Culture for Synthesis of PHA Biopolymers as
Intracellular Product”
`̀̀
Polymer GranulesPolymer GranulesPolymer Chains Below Critical LengthPolymer Chains Below Critical Length
PHB accumulation in Alcaligenes latus’ cytoplasm:Two-Phase Emulsion-Like Polymerization MechanismPHB accumulation in Alcaligenes latus’ cytoplasm:
Two-Phase Emulsion-Like Polymerization Mechanism
CytoplasmCytoplasm
Microbial CultureMicrobial Culture
Poly(3-hydroxybutyrate) PHB
Poly(3-hydroxybutyrate) PHB
PRODUCTIONbio
Bioproduction IP
Metabolic pathway of synthesis and degradation of P(3HB).
P(3HB)n
Substrate
AcCoA
Ac-AcCoA
3-HB
Biomass
3-HBCoA
KrebsCycle
KrebsCycleCO2
O2NADHATP
Nitrogen
ATP
PhaA
PhaB
PhaC
PhaZ
Entner-Doudoroff Pathway
Model Integration at the Cell Level
The activated monomer 3-HBCoA constitutes the link between the two models.
22
PRODUCTIONbio
Bioproduction IP
Initiation
(Monomer Unit) (Synthase Dimer)
+ +(Coenzyme A)
Propagation
+
(Active [n]mer)
(Active [n+1]mer)
Coenzyme A
Chain Transferto Water H2O
Depolymerization
(Depolymerase)
(Inactive [n]mer)
(Inactive Monomer)
+
+
(Active Monomer)
Synthase Dimer
(Inactive [n+1]mer)
H2O
Depolymerase
Polymerization MechanismPolymerization Model
1m ik kE SH M SCoA ESH M P ES SH CoA− + − ⎯⎯→ − ⎯⎯→ − + −
1pm kk
n n nP ES M SCoA P ES M P ES SH CoA+− + − ⎯⎯→ − − ⎯⎯→ − + −
2tk
n nP ES H O D E SH− + ⎯⎯→ + −
Initiation
Depolymerization
Propagation
Termination with H2O
1 1dk
n nD E OH D D E OH−+ − ⎯⎯→ + + −
Assumptions• Polymerase (PhaC), depolymerase (PhaZ) and
water concentrations are constant throughout the course of polymerization.
• Cell death occurring after a certain period of time (i.e. 30h) causes polymer degradation to gradually decrease.
• Kinetic rate constants are independent of chain length.
PRODUCTIONbio
Bioproduction IP
Formulation of Differential Equations
Polymerization Model
Metabolic Model
Live polymer chains of length n
[ ] [ ] [ ][ ] [ ][ ]ni m n p n-1 t n 2
d P * = k E-SH-M δ(n-1) - k P M + k P (n-1) - k P H Odt
⎡ ⎤⎢ ⎥⎣ ⎦
H
[ ][ ]*n *
m n p n
d P= k P M - k P
dt
⎡ ⎤⎣ ⎦ ⎡ ⎤⎣ ⎦
[ ] [ ][ ] [ ] [ ]n * * *t n 2 d n d n d n+1
n=2
d D = k P H O - k D (n-1) + k D δ(n-1) + k D
dt∞
∑H
[ ] ( ) [ ] [ ] [ ]*m m n
n=1
d M= - k M - k M P
dt MJ t∞
∑
[ ] [ ] [ ]*m i
d E-SH-M= k M - k E-SH-M
dt
Intermediate polymer chains of length n
Dead polymer chains of length n
Monomer
Monomer-Synthase Complex
( ) ( )MJ t g , , , , tk Y C J=
23
PRODUCTIONbio
Bioproduction IP
Model Tuning (Fructose 5 g/l)
• The polymerization model was solved with two different numerical methods. • Parameters are estimated using the General Regression Software (GREG).• The model is able to predict the evolution of Mn and polymer yield.• There is a very good agreement between numerical methods.
0.00.51.01.52.02.53.03.54.04.55.0
0 10 20 30 40 50
Time (h)
PHB
(gr/
lt)
ExperimentalPHB - MOMPHB - Fixed Pivot
0.0E+001.0E+052.0E+053.0E+054.0E+055.0E+056.0E+057.0E+058.0E+059.0E+051.0E+06
0 10 20 30 40 50
Time (h)
Mn
ExperimentalM n - M OMM n - Fixed Pivot
PRODUCTIONbio
Bioproduction IP
Model Validation (Fructose 10 g/l)
• The model is able to predict the evolution of Mn and polymer yield.• There is a very good agreement between numerical methods.• In batch cultures a maximum Mn and polymer yield are achieved and
subsequently there is a decrease to a steady-state value.
0.0E+005.0E-01
1.0E+001.5E+002.0E+002.5E+003.0E+003.5E+004.0E+004.5E+005.0E+00
0 10 20 30 40 50
Time (h)
PHB
(gr/
lt)
ExperimentalPHB - MOMPHB - Fixed Pivot
0.0E+001.0E+052.0E+053.0E+054.0E+055.0E+056.0E+057.0E+058.0E+059.0E+051.0E+06
0 10 20 30 40 50
Time (h)
Mn
ExperimentalMn - MOMMn - Fixed Pivot
24
PRODUCTIONbio
Bioproduction IP
1.0E-20
2.0E-08
4.0E-08
6.0E-08
8.0E-08
1.0E-07
1.2E-07
1.4E-07
1.6E-07
1.8E-07
2.0E-07
1.E+02 1.E+03 1.E+04 1.E+05
Chain Length
Con
cent
ratio
n (m
ol lt-1
)
t=2ht=10ht=20ht=30ht=50h
0.0E+00
2.0E-08
4.0E-08
6.0E-08
8.0E-08
1.0E-07
1.2E-07
1.4E-07
1.6E-07
1.8E-07
2.0E-07
1.E+02 1.E+03 1.E+04 1.E+05
Chain Length
Con
cent
ratio
n (m
ol lt-1
)
t=2ht=10h
t=20ht=50h
Fructose 5 g/l Batch Fructose 5 g/l Fed-batch
• Chain length distributions reflect the behavior of Mn and polymer yield.
Investigation of MWD Evolution
PRODUCTIONbio
Bioproduction IP
The evolution of the cell mass distribution under the combined action of cell growth and division is described by the following equation:
( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )m
n m,tG m,S n m,t 2 Γ m ,S P m,m n m ,t dm Γ m,S n m,t
t m
∞∂ ∂ ′ ′ ′ ′+ = −⎡ ⎤⎣ ⎦∂ ∂ ∫
The PBE is coupled to the mass balance for the substrate concentration.
( ) ( )0
dS 1 G m,s n m, t dmdt Y
∞
= ∫
The Population Balance Equation (PBE)
( )n m t, : number of cells with mass between [ ], +m m dm per unit biovolume at time t, 1 3− −⋅g m .
( )G m,S : growth of cells with mass m, g/s.
( ),Γ m S : division rate (intensity) of cells with mass m, 1−s .
( )′P m m, : partitioning function, i.e., probability that a mother cell with mass ′m will give birth to a daughter cell with mass m, 3−m .
Y: yield coefficient(g substrate/g biomass)
25
PRODUCTIONbio
Bioproduction IP
Case I: Linear Growth - Equal partitioning
1020
30
0
0.5
1
0
1
2
3
4
5
Time (h)
Cell Mass (m/m0 )
n(m
,t)
Case II: Linear Growth – Unequal Partitioning
1020
30
0
0.5
1
0
1
2
3
4
5
Time (h)
Cell Mass (m/m 0 )
n(m
,t)
Constant Substrate Concentration
For linear cell growth rate and equal partitioning the cell mass distribution exhibits a periodic behavior with a frequency equal to the cell doubling time Td=5h. For linear cell growth rate and unequal partitioning a state of balanced growth is gradually achieved.
PRODUCTIONbio
Bioproduction IP
Reactor level
Modelling Challenges
Ideal Mixing
Full CFD Model
Multizonal Model
CFD/Multizonal Model
Distributed SegregatedCell population level
Single-cell level
• Define the level of the model complexity.
• Detailed mathematical descriptions are of great value for the design of bioprocesses, usually lead to computationally intractable models.
UnstructuredStructured
Reactor level
26
PRODUCTIONbio
Bioproduction IP
Conclusions
• The microbial PHA production process is a multi-parametric system
• The physiological state of the culture is determinant for both the quality and the quantity of the produced biopolymers
• Exhaustive investigation and mapping of the influence of all the operating parameters on both the physiological state of the culture and the productivity and quality of the biopolymers is necessary
• A model-based optimization of these production processes and simulation of the biopolymer molecular properties will enhance their competitiveness and will assist their economic viability.
• Operating profiles, product recovery techniques, and reactor configuration were explored through an experimental- and a model-based approach
• The conceptual framework for the development of integrated metabolic, polymerization and population models at a reactor level accounting for heat and mass transfer phenomena was presented
• An integrated metabolic/polymerization model was developed based on experimental data from fermentation of Alcaligenes species.