Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576 S205

oriented view. A goal is a link to the database on seed content ofplants SOFA (Aitzetmüller et al., 2003). Our database is dynami-cally linked with other databases of biological information as KEGG(http://www.genome.jp/kegg/pathway.html).

The database is organized in records starting with the organismidentification at the species and infraspecific level of plants, eukary-otic algae, fungi, and Cyanobacteria. The data can be extracted informat usuful for analysis with statistical tools.

Future development will aim to integrate BIOLIP with othermore general purpose biological information database (Genbank,PDB and so on) to favourish a better understanding of the connec-tion between the presence of a specific fatty acid with the geneticknowledge of an organism.

New data sent to the BIOLIP database by researchers shouldbe sent in Excel or tab delimited text format, containing all thenecessary information: organism with appropriate identification,provenance, published article and/or analytical method and thetotal amount of lipids and the relative amount of each fatty acid.

Acknowledgements

We thank the Fondazione Cassa di Risparmio di Pistoia e Pesciafor the financial support.

References

Aitzetmüller, K., Matthäus, B., Friedrich, H., 2003. A new database for seed oil fattyacids – the database SOFA. Eur. J. Lipid Sci. Technol. 105, 92–103.

Schenk, P.M., Thomas-Hall, S.R., Stephens, E., Marx, U.C., Mussgnug, J.H., Posten,C., Kruse, O., Hankamer, B., 2008. Second Generation Biofuels: High-EfficiencyMicroalgae for Biodiesel Production. Bioenerg. Res. 1, 20–43.

doi:10.1016/j.jbiotec.2010.09.012

[P-C.47]

Determination of the rheologic behavior of fermentation brothin biogas plants

J. Renpenning 1, P. Mähnert 2, V. Pelenc 3, R. Lopez-Ulibarri 4, P.Neubauer 1, S. Junne 1,∗, R.G. Berger 2

1 Technische Universität Berlin, Germany2 KTG Biogas AG, Germany3 DSM Biopract GmbH, Germany4 DSM Nutritional Products Ltd., SwitzerlandKeywords: Biogas; Rheology; Viscosity; Shear rate

The knowledge of the rheologic behavior of the fermentationbroth for the production of biogas from agricultural streams as sub-strates is important for process and plant optimization. It directlyinfluences the power input required for efficient mixing and thedegree of inhomogeneity within the reactor. The exact determina-tion of this parameter is crucial, since the culture broth in samplesis still active and changes its rheologic behavior during the trans-port for analysis. Due to the inhomogeneity in the sample, whichcontains solid particles of an uneven size, the utilization of con-ventional viscometers is not suitable. A portable device that canbe transported to the biogas plant and where the viscosity can bemeasured immediately after sampling is presented in this study.The theoretical background of the determination of the viscosityrelies on the torque measurement under strongly laminar condi-tions at Reynolds numbers below 10. This methodology has alreadybeen used to determine the viscosity and rheologic characteristicsof substrate slurries or filamentous fungi culture broths(Houchinand Hanley., 2004), (Bongenaar. et al., 1973).

The device was characterized by determining the constants forthe system and shear rate. The sensitivity of the method was provenat different stirrer rates and geometries. Different models describ-ing the viscosity having shear rates as variable were applied. Wehave observed that the change of viscosity of the culture brothdue to substrate degradation can be monitored with the presentedmethod. Regression analysis between rheologic and product mea-surement can be performed in order to evaluate the influence ofrheology on the biogas yield, energy consumption and process sta-bility.

References

Houchin, T.L., Hanley, T.R., 2004. Measurement of rheology of distiller’s grain slurriesusing a helical impeller viscometer. Applied Biochemistry and Biotechnology113–16, 723–732.

Bongenaar, J.J.T.M., et al., 1973. Method for Characterizing Rheological Properties ofViscous Fermentation Broths. Biotechnology and Bioengineering 15.1, 201–206.

doi:10.1016/j.jbiotec.2010.09.013

[P-C.48]

Novel eco-friendly aliphatic copolyesters: structure-propertyrelationship and biodegradation behaviour

Annamaria Celli 1,∗, Paola Marchese 1, Simone Sullalti 1, CorradoBerti 1, Giancarlo Barbiroli 1, Sophie Commereuc 2

1 Univesity of Bologna, Italy2 Université Blaise Pascal and Ecole Nationale Supérieure de Chimie deClermont-Ferrand, FranceKeywords: biopolyesters; Copolymerization; Biodegradation; 1,4-cyclohexylene

Nowadays, literature shows a great interest in developing newpolyesters, with the desired final properties according to the possi-ble applications, by combining different monomers available frompetrolchemical industry or, more recently, from biomass.

1,4-cylohexanedicarboxylic acid (or the corresponding diester)is a very interesting monomer, relatively less studied and charac-terized, instead, by notable properties, such as a potential originfrom renewable resources. The 1,4-cyclohexylene unit is struc-turally rigid and can induce relative stiffness in the macromolecularchain in which it is inserted and, then, improve the poor physicaland mechanical properties typical of the aliphatic polyesters. More-over, it has been found that the final properties of the polyesterscontaining 1,4-cyclohexane dicarboxylate units strongly dependon the stereochemistry of the rings. Indeed, a high percentage ofthe trans isomer in the cycloaliphatic units favours a high level ofcrystallinity and relatively high melting temperature. On the otherhand, a low trans content induces low crystallinity up to a fullyamorphous phase.

Therefore, we have combined this monomer with diols andother diacids, for example with 1,4-butanediol, dimethyl adi-pate or 1,12-dodecanedioic acid, to obtain novel copolyesters.Interesting correlation between molecular structure and thermo-mechanical properties have been found, indicating that the finalproperties can be easily modulated by changing the length of the–(CH2)- sequences, the isomeric ratio of the 1,4-cyclohexyleneunits, and the molar composition of the copolyesters. Moreover,biodegradation tests have been carried out in an aqueous mineralnutrient medium inoculated by micro-organisms resulting fromactive ground or compost. Some copolyesters present a very highbiodegradation rate, mainly connected to a low level of crystallinity.

Therefore, the use of the 1,4-cycloaliphatic unit as buildingblocks for novel aliphatic polyesters can lead to opti-

S206 Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576

mum combinations of thermo-mechanical properties andbiodegradability.

doi:10.1016/j.jbiotec.2010.09.014

[P-C.49]

New polymers from renewable resources: synthesis, character-ization, and photodurability of aliphatic polyesters containingglycerol

Annamaria Celli 1,∗, Paola Marchese 1, Simone Sullalti 1, CorradoBerti 1, Sophie Commereuc 2, Vincent Verney 2

1 University of Bologna, Italy2 Université Blaise Pascal and Ecole Nationale Supérieure de Chimie deClermont-Ferrand, FranceKeywords: Biopolyesters; Glycerol; Photodegradability;Poly(alkylene dicarboxylate)

Aliphatic polyesters, synthesized from monomers obtainablefrom biomasses, are an interesting class of materials which combineexcellent properties, such as biodegradability and biocompatibility,with quite poor physical properties and often high costs. For thisreason modification of aliphatic polyesters have recently attractedconsiderable attention.

In particular, by considering the poly(alkylene dicarboxylate)s,linear aliphatic polyesters synthesized by combination of diols withdicarboxylic acids, one of the possible strategies to improve thethermo-mechanical characteristics is the chemical modificationof the macromolecular architecture, by addition of a multifunc-tional monomer. Here we present the results of the chemicalmodification of the poly(butylene dodecanoate), derived from 1,4-butanediol and 1,12-dodecanedioic acid, by addition of glycerol, athreefunctional alcohol, byproduct of the production of biodiesel.The synthesis of the novel polyesters, characterized by a glyc-erol content varying from 0.5 to 2.0 mol%, has been optimized.The analysis of the molecular structure, carried out by 1H NMRspectroscopy, and the chemical properties of the materials (forexample, solubility) reveal a complex polymer network, due to thereactivity of all the –OH groups of glycerol. Even if the thermalproperties of the crystal phase seem not affected by the presenceof the glycerol, the mechanical properties change with respectto those of the homopolymer. Moreover, as the materials, duringtheir service life, can be submitted to photodegradation, as well asbiodegradation and hydrolytic degradation, due to outdoor use, thedurability is a property of great importance. Therefore, a study ofthe photodegradability of the novel polyesters has been carried outand attention has been paid on the molecular structure evolutionupon photodegradation monitored by melt rheology. The differ-ent mechanisms occurring during photoageing, chain scissions andthree-dimensional network formation, have been identified.

doi:10.1016/j.jbiotec.2010.09.015

[P-C.50]

Studies on glucose assay in real samples using glucose oxidasebiosensors with different membrane supports

O. Bizerea Spiridon 1, G. Preda 1, B. Vlad-Oros 1, M. Vintila 1, M.Dragomirescu 1,2,∗

1 West University of Timisoara, Romania2 Banat’s University of Agricultural Science and Veterinary MedicineTimisoara, RomaniaKeywords: Glucose oxidase; Glucose potentiometric biosensor;PVA membrane; Glutaraldehyde

Biosensors for glucose using glucose oxidase (GOx) (EC 1.1.3.4.)were developed. The sensors could be used for glucose assay in0.75·10-4 M – 10-2 M concentration range (Pisoschi and Danet,2004),(Pisoschi et al., 2006). Our preliminary studies were focusedon the influence of the GOx immobilization in/on the biosensormembrane with glutaraldehyde (GA) or tetrakis (2-hydroxyethyl)orthosilicate (THEOS)) (Vlad-Oros et al., 2009). The results showedthat, in the case of enzyme immobilization with glutaraldehyde, thebiosensor sensitivity increases significantly, especially at low glu-cose concentrations (0.75·10-4 M – 1.25·10-4 M). We attempted todevelop a biosensor with biodegradable membrane, but the perfor-mances of this biosensor proved to be lower, especially regardingthe enzymatic reaction rate and sensitivity (Bizerea-Spiridon etal., 2008). The glucose biosensor using polyvinyl alcohol (PVA) asmembrane lead to improved performances for dilute glucose solu-tions assays (10-4 M). Thus, the sensibility, the response time anddata reproducibility were enhanced.The biosensors with enzymebounded with GA on celophane and PVA respectively can be usedto assay glucose in synthetic solutions (physiological serum, per-fusable solutions) or natural products (juices or vines).

References

Pisoschi, A.M., Danet, A.F., 2004. Constructia si determinarea caracteristiciloranalitice ale unui biosenzor potentiometric pentru glucoza. Rev. Chim. 55 (11),843–850.

Pisoschi, A.M., Danet, A.F., Negulescu, Gh.P., 2006. Glucose determination bycellophane-based and nylon-based enzymic electrodes; application on juicesand wine analysis. EJEAFChe 5 (1), 1185–1194;.

Vlad-Oros, B., Bizerea-Spiridon, O., Preda, G., Chiriac, A., 2009. Studies regardingthe influence of the enzyme immobilization methods on the electrodic surfaceupon the performances of the glucose biosensor. Rev. Chim. (Bucuresti) 60 (7),639–648.

Bizerea-Spiridon, O., Vlad-Oros, B., Preda, G., Chiriac, A., Obtaining and characteri-zation of a biosensor based on biodegradable membrane used for glucose assay,ECOMAT sept. 2008, Bucuresti, Romania, p.110 – 113.

doi:10.1016/j.jbiotec.2010.09.016

[P-C.51]

Steam explosion of cane bagasse using phosphoric acid as thepretreatment catalyst

A.P. Pitarelo 1, D. Szczerbowski 1, P.M. Ndiaye 1, A. ZandonáFilho 1,2, L.P. Ramos 1,∗

1 Federal University of Paraná, Brazil2 Tuiuti University, BrazilKeywords: Cane bagasse; Pretreatment; Hydrolysis; Bioethanol

The criteria for pretreatment optimization is changing remark-ably as more efficient enzyme cocktails are made available forsaccharification together with microorganisms that are capableof fermenting pentoses and hexoses simultaneously. This workwas carried out as part of the CaneBioFuel project to revisit the