Research Group

Researchers
Dr Aris Xenakis, Researcher Director (Program Head)
Dr. Vassiliki Papadimitriou, Researcher C', Chemist
Dr. Maria Zoumbanioti, Research Engineer C'Chem. Eng.

Post-Doc Collaborating Researchers
Dr. Haris Stamatis, Chemist
Dr. Spyros Avramiotis, Chemist


PhD Students
Mrs. Evanggelia Tzika, Chemist

Msc. Students
Tina Filippou, Biologist

Technicians
Mr. G.Sotiroudis, MSc. Pharmasist
Mrs. Stathis Kaldanis

Aims of the Programme

Model of Reverse Micelle

The Biomimetics and Nanobiotechnology Programme deals with studies on the behavior of biomolecules, such as enzymes, in model systems simulating their natural environment. The studies are focused on structural and functional aspects of the biomolecules when hosted in environments with restricted water contents, such as microemulsions.

Water-in-oil microemulsions are fine dispersions of water in an organic non-polar solvent (oil) stabilized by one monolayer of surfactant molecules. These systems allow the simultaneous solubilization of compounds with different polarities, such as lipophilic ones located in the continuous organic phase, or hydrophilic ones enclosed in the dispersed aqueous phase, which can react through an enormous interface. It is, thus, possible to encapsulate enzymes and to use them as catalysts in reactions of substrates non soluble in water. Microemulsions can also be used to study membrane enzymes, as well as media for the protection of enzymes against denaturation.

Ενσωμάτωση ενζύμου σε αντίστροφα μικκύλια. Πιθανές θέσεις εντοπισμού του ενζύμου

Four main activities are developed within the Biomimetics programme:
Structure and function studies of enzymes in microemulsions
Structural studies of microemulsions, using spectroscopic techniques
Development of novel nanobiotechnological applications
Biotechnological applications of olive oil

Schematic representation of microemulsions

AOT in the absence of lipase    AOT in the presence of lipase

lecithin in the absence of lipase  lecithin in the presence of lipase

These studies have yielded various applications, which are developed within the Industrial Enzymology Unit of IBRB, in collaboration with Food, Pharmaceutics, and Cosmetics industries.

Current Externally Funded projects:

1. Program ΕΠAN - Liaison Offices of Universities and Research Centers. (2005-8) ''Development of a Liaison office at the NHRF''. Budget: 300.000,00 € Coordinator NHRF: A. Xenakis
2. Program ΠΑΒΕΤ 2005: ''Production of high added value products by the biotechnological application of lipases as biocatalysts'' Contractor: ΝΕΟΚΕΜ SA Budget: 35.000,00 €. Coordinator NHRF: A. Xenakis
3. Program ΕΠΑΝ Franco Hellenic Collaboration 2006-7 ''Biocatalysis by immobilized enzymes in mesoporous materials for the biotechnological production of high added value products'' Budget: 12.400,00 €. Coordinator NHRF: A. Xenakis
   Collaboration with the research group of: Dr M.J. Stébé, Equipe Physico-chimie des Colloides (UMR 7565) Faculté des Sciences Université de Nancy
4. Program ΕΠΑΝ Cyprus Hellenic Collaboration 2006-7 ''Quality and stability of virgin olive oil. The role of endogenous enzymes and antioxidants - biotechnological applications'' Budget: 11.740,00 €. Coordinator Dr V. Papadimitriou
   Collaboration with the research groups of: Prof. Ep. Leondidis, Chemistry Dept. University of Cyprus, Nicosia
5. MED Programme 2009-2011 ''Mediterranean Transnational Technology Transfer - MET3'' Budget: 360.000 €
6. South East Europe - Trasnational Cooperation Programme 2009-2011, ''Solutions and Interventions for the Technological Transfer and the Innovation of the Agro-Food Sector in the South East Regions'', SEE/A/160/1.1/X Budget: 238.118 €
   

Complete list of projects

Selected Recent Publications

1. A. Xenakis, V. Papadimitriou, T.G. Sotiroudis (2010) ''Colloidal structures in natural oils'' Curr.Opinion Colloid Interface Sci. accepted
2. F. Michaux, M. Zoumpanioti, M. Papamentzelopoulou, M. J. Stébé., J. L. Blin, A. Xenakis (2010) ''Immobilization and activity of Rhizomucor miehei lipase. Effect of the matrix properties prepared from nonionic fluorinated surfactants''. Proc.Biochem. 45, 39-46
3. E. D.Tzika, T.G. Sotiroudis, V.Papadimitriou, A.Xenakis (2009) ''Characterization of peroxidase activity in oil producing koroneiki olives" European Food Research and Technology., 228, 487- 495.
4. A. Xenakis, V. Papadimitriou, H. Stamatis, F. N. Kolisis (2009) ''Biocatalysis in microemulsuions'' in "Microemulsions: Properties and Applications" Surfactant Sci.Ser., Vol.144, pp.349-385. Ed. M.Fanun.,CRC Press, Jerusalem, Israel
5. E. D.Tzika, V.Papadimitriou, T.G. Sotiroudis, A.Xenakis (2008) ''Oxidation of oleuropein: Electron paramagnetic resonance and spectrophotometric studies'', Eur.J.Lipid Sci.Technol., 110, 149-157.
6. E. D.Tzika, V.Papadimitriou, T.G. Sotiroudis, A.Xenakis (2008) ''Antioxidant properties of fruits and vegetables shots and juices: An Electron Paramagnetic Resonance study'', Food Biophys. 3, 48-53
7. V. Papadimitriou, S. Pispas, S. Syriou, A.Pournara, M. Zoumpanioti, T. G. Sotiroudis, A.Xenakis (2008) ''Biocompatible Microemulsions based on Limonene: Formulation, Structure and Applications'' Lamgmuir, 24, 3380-3386.
8. M. Zoumpanioti, P. Parmaklis, P. Dominguez de Maria, H. Stamatis, J.V. Sinisterra, A. Xenakis. (2008) ''Esterification reactions catalyzed by lipases immobilized in organogels. Effect of temperature and substrate diffusion'' Biotechnol. Lett. 30,1627-1631
9. V. Papadimitriou, T.G. Sotiroudis, A. Xenakis, (2007) Olive oil microemulsions: enzymatic activities and structural characteristics, Langmuir, 23, 2071-7.
10. S. Avramiotis, V. Papadimitriou, E. Hatzara, V. Bekiari, P. Lianos, A. Xenakis (2007) ''Lecithin Organogels Used as Bioactive Compounds Carriers. A Microdomain Properties Investigation'' Langmuir, 23, 4438-4447
    

Complete list of publications

Collaborations with Industries