Berezina N.,Materia Nova
Biotechnology Journal | Year: 2012
In the current context of global warming, the substitution of conventional plastics with bioplastics is a challenge. To take up this challenge, we must meet different technical and economic constraints. In the case of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), the technical properties can be modulated by varying the 3-hydroxyvalerate content. 3-Hydroxyvalerate (3-HV) enhancement is an issue; therefore, simultaneous evaluation of several 3-hydroxyvalerate-enhancing substrates through fractional factorial design of experiments is described. Eight substrates citric, valeric, propionic, and levulinic acids; propanol; pentanol; and sodium propionate were studied for 3-HV enhancement, and sodium glutamate was studied for biomass and polyhydroxyalkanoate (PHA) enhancement. The most efficient 3-hydroxyvalerate-enhancing factors were levulinic acid, sodium propionate, and pentanol; however, pentanol, at a concentration of 1 g/L, had an extremely negative influence on biomass production and the PHA content of cells. The effect of the inoculum nutrient composition on the final 3-HVcontent was also evaluated. These results showed that the most efficient combination for the production of high 3-HVcontent in PHBV was primary inoculum growth on mineral medium followed by fermentation for 48 h with levulinic acid and sodium propionate (at 1 g/L) as the only carbon sources. This allowed us to produce PHBV with a 3-HVcontent of 80 mol % and overall volumetric and specific productivities of 2 mg/L/h and 3.9 mg/gCDW/h, respectively, with the addition of only 2 g/L of inducing substances. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Berezina N.,Materia Nova
New Biotechnology | Year: 2013
In the global context of increased concerns for our environment, the use of bioplastics as a replacement for existing petroleum-based polymers is an important challenge. Indeed, bioplastics hardly meet economical and technical constraints. One, of the most promising among currently studied bioplastics, is the polyhydroxyalkanoate (PHA). To circumvent the economical issue for this particular biopolymer one solution can be the enhancement of the overall productivity by the improvement of the nutritional medium of the microorganism producing the biopolymer. Thus, several nutrition media, supplemented or not with sodium glutamate, were tested for the growth and the PHA production by Cupriavidus necator DSM 545 strain. The most efficient for the biomass and the PHA production improvement were found to be the Luria broth (LB) and the Bonnarme's media, both supplemented with 10. g/L sodium glutamate. Hence the overall productivity was 33 times enhanced comparing to traditional cultivation methods. These results open a new route for the PHA production by C. necator which appears to be more suitable on a rich, or enriched, medium with no limiting factors. © 2012 Elsevier B.V. Source
Kanta A.-F.,University of Mons |
Poelman M.,Materia Nova |
Decroly A.,University of Mons
Solar Energy Materials and Solar Cells | Year: 2015
TiO2 nanotubes have demonstrated perspective applications in the photovoltaic field. They can reduce both the transport dimensionality and the recombination of the photoinjected electrons. In this paper, arrays of TiO2 nanotubes were fabricated by anodization of Ti foils in an ethylene glycol solution containing hydrofluoric acid (HF) under a constant voltage. From field emission scanning electron microscopy (FE-SEM) images, we observed the microstructure of titania nanotubes. Images show that, as-anodized, the surface of the nanotubes is covered with a precipitate. Ultrasonic treatment was used to remove this precipitate. X-ray diffraction (XRD) results show that the as-anodized amorphous TiO2 nanotubes are converted to crystalline anatase after the samples have been annealed at 500 °C during 2 h. Electrochemical behaviour (in terms of charge transfer resistance) was investigated by electrochemical impedance spectroscopy (EIS). The annealed samples were characterized by electrochemical tests. A schematic representation of the TiO2 nanotubes consisting of two layers (i.e. dense and nanoporous) is proposed to explain the obtained results. © 2014 Elsevier B.V. All rights reserved. Source
Materia Nova and University of Mons | Date: 2011-01-26
A conventional polymer is grafted from a plasma polymer layer provided at a substrate surface by radical polymerisation initiated from plasma induced radicals present at or in the plasma polymer, particularly radicals provided during deposition of the plasma polymer.
Agency: Cordis | Branch: FP7 | Program: CP | Phase: OCEAN 2013.3 | Award Amount: 9.97M | Year: 2013
The BYEFOULING project will address high volume production of low toxic and environmentally friendly antifouling coatings for mobile and stationary maritime applications. The technology will fulfil the coating requirements as a result of the incorporation of novel antifouling agents and a new set of binders into coating formulations for maritime transportation and fishing vessels, floating devices and aquaculture. The main vision of BYEFOULING is to provide the means for industrial, cost-effective and robust manufacturing of antifouling coatings in Europe, where SMEs are both coating components developers and production technology providers. A set of procedures, guidelines and fabrication tools will be developed, enabling short time to market for new coating concepts. The main goal of BYEFOULING is to design, develop and upscale antifouling coatings with enhanced performance compared to current available products. The approach in BYEFOULING is to tackle the different stages of the biofouling process using innovative antifouling agents, covering surface-structured materials, protein adsorption inhibitors, quorum sensing inhibitors, natural biocides and microorganisms with antifouling properties. Encapsulation of the innovative compounds in smart nanostructured materials will be implemented to optimize coating performance and cost all along their life cycle. A proof-of-concept for the most promising candidates will be developed and demonstrators will be produced and tested on fields. BYEFOULING will combine a multidisciplinary leading research team from 11 European countries, which are already acting worldwide in the scientific community, with highly relevant and skilled technological partners, to build a consortium able to develop a full production line for antifouling coatings in Europe. Readily available low toxic and cost-effective antifouling coatings will increase the efficiency of maritime industry and be the enabling technology to realize new products.