Production of ValueAdded

1
Production of Value-Added Bacterial
Polysaccharides from Glycerol Byproduct from the
Biodiesel Industry
Maria A. M. Reis REQUIMTE/CQFB, Department of
Chemistry, FCT/Universidade Nova de Lisboa,
Portugal
2
INTRODUCTION
3
INTRODUCTION
Low-cost Substrates
Agricultural and Industrial wastes and byproducts
Glycerol

• 2007
• Europe 600.000 tons glycerol
• USA gt120.000 tons glycerol

4
OBJECTIVES
Reis et al. (2008) Patent WO 2008/127134
5
EPS PRODUCTION
Pseudomonas oleovorans
6
EPS PRODUCTION
7
EPS PRODUCTION
viscosity built up concomitant with EPS production
culture broth develops non-Newtonian
characteristics, acting as a pseudoplastic fluid
loss of homogeneity in the bioreactor (mixing,
mass, oxygen and heat transfer)
8
EPS PRODUCTION
1 crude polymer (a) Continuous process
9
EPS EXTRACTION
10
EPS CHARACTERIZATION
Freitas et al. (2009) Bioresource Technology,
100, 859-865
11
EPS CHARACTERIZATION
Rheology

• Newtonian behaviour at low shear rates

Polymer concentration 10 g L-1 in 0.1M NaCl, 25ºC
3
10
2
10
1
10
similar to Guar gum
(Pa.s)
0
h
10
better viscosity enhancing properties than CMC
and alginate
-1
10
less viscous than xanthan at low shear rates
-2
10
-2
-1
0
1
2
3
4
10
10
10
10
10
10
10
-1
g
(s
)
Hilliou et al. (2009) Carbohydrate Polymers (in
press) (doi 10.1016/j.carbpol.2009.05.011)
12
EPS CHARACTERIZATION
Rheology
Freitas et al. (2009) Carbohydrate Polymers (in
press) (dx.doi.org/10.1016/j.carbpol.2009.05.016)
13
EPS CHARACTERIZATION
Rheology
14
EPS CHARACTERIZATION
Emulsion forming and stabilizing capacity
E24 for 0.8 EPS solutions against several
hydrophobic compounds
6 mL hexadecane 4 mL EPS dispersion (wt)
15
EPS CHARACTERIZATION
Emulsion forming and stabilizing capacity
16
EPS CHARACTERIZATION
Flocculating capacity
(polymer dispersions 0.1 wt)
40 mL kaolin suspension 5 mL CaCl2 (10 wt)
0.25 mL polymer dispersion H2O (up to 50 mL)
17
EPS CHARACTERIZATION
Film-forming capacity

• flexible and transparent

• hygroscopic

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Emulsifying activity
foods cosmetics paints
bioemulsifier biosurfactant
Reology
foods pharmaceuticals, cosmetics paints, paper,
and petroleum industries
thickening, binding, texturing and stabilizing
agent in liquid systems
Flocculating activity
water and wastewater treatment, foods, mining
industry
bioflocculant agent
Film-forming capacity
barriers encapsulation packaging
biodegradable films
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CONCLUSIONS
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Team Rui Oliveira, Filomena Freitas Vítor D.
Alves, Cristiana Torres, Mónica Carvalheira Nuno
Costa