The transition to a biobased economy necessitates utilizing renewable resources as a sustainable alternative to traditional fossil fuels. Bioconversion is a way to produce many green chemicals from renewables, e.g., biopolymers like PHAs. However, fermentation and bioconversion processes mostly rely on expensive, and highly refined pure substrates. The utilization of crude fractions from biorefineries, especially herbaceous lignocellulosic feedstocks, could significantly reduce costs. This presentation shows the microbial production of PHA from such a crude stream by a wild-type thermophilic bacterium Schlegelella thermodepolymerans [1]. Specifically, it uses crude xylose-rich fractions derived from a newly developed biorefinery process for grassy biomasses (the ALACEN process). This new stepwise mild flow-through biorefinery approach for grassy lignocellulosic biomass allows the production of various fractions: a fraction containing esterified aromatics, a monomeric xylose-rich stream, a glucose fraction, and a native-like lignin residue [2]. The crude xylose-rich fraction was free of fermentation-inhibiting compounds meaning that the bacterium S.thermodepolymerans could effectively use it for the production of one type of PHA, polyhydroxybutyrate. Almost 90% of the xylose in the refined wheat straw fraction was metabolized with simultaneous production of PHA, matching 90% of the PHA production per gram of sugars, comparable to PHA yields from commercially available xylose. In addition to xylose, S. thermodepolymerans converted oligosaccharides with a xylose backbone (xylans) into fermentable xylose, and subsequently utilized the xylose as a source for PHA production. Since the xylose-rich hydrolysates from the ALACEN process also contain some oligomeric xylose and minor hemicellulose-derived sugars, optimal valorization of the C5-fractions derived from the refinery process can be obtained using S. thermodepolymerans. This opens the way for further exploration of PHA production from C5-fractions out of a variety of herbaceous lignocellulosic biomasses using the ALACEN process combined with S. thermodepolymerans. Overall, the innovative utilization of renewable resources in fermentation technology, as shown herein, makes a solid contribution to the transition to a biobased economy.[1] W. Zhou, D.I. Colpa, H. Permentier, R.A. Offringa, L. Rohrbach, G.J.W. Euverink, J. Krooneman. Insight into polyhydroxyalkanoate (PHA) production from xylose and extracellular PHA degradation by a thermophilic Schlegelella thermodepolymerans. Resources, Conservation and Recycling 194 (2023) 107006, ISSN 0921-3449, https://doi.org/10.1016/j.resconrec.2023.107006. [2] S. Bertran-Llorens, W.Zhou. M.A.Palazzo, D.I.Colpa, G.J.W.Euverink, J.Krooneman, P.J.Deuss. ALACEN: a holistic herbaceous biomass fractionation process attaining a xylose-rich stream for direct microbial conversion to bioplastics. Submitted 2023.
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The transition to a biobased economy necessitates utilizing renewable resources as a sustainable alternative to traditional fossil fuels. Bioconversion is a way to produce many green chemicals from renewables, e.g., biopolymers like PHAs. However, fermentation and bioconversion processes mostly rely on expensive, and highly refined pure substrates. The utilization of crude fractions from biorefineries, especially herbaceous lignocellulosic feedstocks, could significantly reduce costs. This presentation shows the microbial production of PHA from such a crude stream by a wild-type thermophilic bacterium Schlegelella thermodepolymerans [1]. Specifically, it uses crude xylose-rich fractions derived from a newly developed biorefinery process for grassy biomasses (the ALACEN process). This new stepwise mild flow-through biorefinery approach for grassy lignocellulosic biomass allows the production of various fractions: a fraction containing esterified aromatics, a monomeric xylose-rich stream, a glucose fraction, and a native-like lignin residue [2]. The crude xylose-rich fraction was free of fermentation-inhibiting compounds meaning that the bacterium S.thermodepolymerans could effectively use it for the production of one type of PHA, polyhydroxybutyrate. Almost 90% of the xylose in the refined wheat straw fraction was metabolized with simultaneous production of PHA, matching 90% of the PHA production per gram of sugars, comparable to PHA yields from commercially available xylose. In addition to xylose, S. thermodepolymerans converted oligosaccharides with a xylose backbone (xylans) into fermentable xylose, and subsequently utilized the xylose as a source for PHA production. Since the xylose-rich hydrolysates from the ALACEN process also contain some oligomeric xylose and minor hemicellulose-derived sugars, optimal valorization of the C5-fractions derived from the refinery process can be obtained using S. thermodepolymerans. This opens the way for further exploration of PHA production from C5-fractions out of a variety of herbaceous lignocellulosic biomasses using the ALACEN process combined with S. thermodepolymerans. Overall, the innovative utilization of renewable resources in fermentation technology, as shown herein, makes a solid contribution to the transition to a biobased economy.[1] W. Zhou, D.I. Colpa, H. Permentier, R.A. Offringa, L. Rohrbach, G.J.W. Euverink, J. Krooneman. Insight into polyhydroxyalkanoate (PHA) production from xylose and extracellular PHA degradation by a thermophilic Schlegelella thermodepolymerans. Resources, Conservation and Recycling 194 (2023) 107006, ISSN 0921-3449, https://doi.org/10.1016/j.resconrec.2023.107006. [2] S. Bertran-Llorens, W.Zhou. M.A.Palazzo, D.I.Colpa, G.J.W.Euverink, J.Krooneman, P.J.Deuss. ALACEN: a holistic herbaceous biomass fractionation process attaining a xylose-rich stream for direct microbial conversion to bioplastics. Submitted 2023.
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The postdoc candidate, Giuliana Scuderi, will strengthen the connection between the research group Biobased Buildings (BB), (collaboration between Avans University of Applied Sciences and HZ University of Applied Sciences (HZ), and the Civil Engineering bachelor programme (CE) of HZ. The proposed research aims at deepening the knowledge about the mechanical properties of biobased materials for the application in the structural and infrastructural sectors. The research is relevant for the professional field, which is looking for safe and sustainable alternatives to traditional building materials (such as lignin asphalt, biobased panels for bridge constructions, etc.). The study of the mechanical behaviour of traditional materials (such as concrete and steel) is already part of the CE curriculum, but the ambition of this postdoc is that also BB principles are applied and visible. Therefore, from the first year of the programme, the postdoc will develop a biobased material science line and will facilitate applied research experiences for students, in collaboration with engineering and architectural companies, material producers and governmental bodies. Consequently, a new generation of environmentally sensitive civil engineers could be trained, as the labour market requires. The subject is broad and relevant for the future of our built environment, with possible connections with other fields of study, such as Architecture, Engineering, Economics and Chemistry. The project is also relevant for the National Science Agenda (NWA), being a crossover between the routes “Materialen – Made in Holland” and “Circulaire economie en grondstoffenefficiëntie”. The final products will be ready-to-use guidelines for the applications of biobased materials, a portfolio of applications and examples, and a new continuous learning line about biobased material science within the CE curriculum. The postdoc will be mentored and supervised by the Lector of the research group and by the study programme coordinator. The personnel policy and job function series of HZ facilitates the development opportunity.
Recent research by the renowned Royal Institution of Chartered Surveyors (RICS) shows that more than 2/3 of all CO2 is emitted during the building process and less than 1/3 during use to heat the building and the tap water. Lightweight, local and biobased materials such as biocomposites to replace concrete and fossil based cladding are in the framework of climate change, a necessity for future building. Using plant fiber in polymer composites is especially interesting for construction since natural fibers exhibit comparative good mechanical properties with small specific weight, which defines the potential for lightweight constructions. The use of renewable resources, will affect the ecosystem favorably and the production costs of construction materials could also decrease. However, one disadvantage of natural fibers in plastics is their hydrophilic properties. In construction the materials need to meet special requirements like the resistance against fluctuating weather conditions (Ticoalu et al., 2010). In contrast to synthetic fibers, the natural ones are more moisture- and UV-radiation-sensitive. That may lead to degradation of these materials and a decreasing in quality of products. (Lopez et al., 2006; Mokhothu und John, 2017) Tanatex and NPSP have approached CoE BBE/Avans to assist in a study where fibres impregnated with the (modified) Tanatex products will be used for reinforcement of thermoset biopolymers. The influence of the different Tanatex products on the moisture absorption of natural/cellulosic fibers and the adhesion on the fibers on main composite matrix will be measured. The effect of Tantex products can optimize the bonding reaction between the resin and the fibers in the (bio) composite and result to improved strength and physico-chemical properties of the biocomposite materials. (word count: 270)
Phosphorus is an essential element for life, whether in the agricultural sector or in the chemical industry to make products such as flame retardants and batteries. Almost all the phosphorus we use are mined from phosphate rocks. Since Europe scarcely has any mine, we therefore depend on imported phosphate, which poses a risk of supply. To that effect, Europe has listed phosphate as one of its main critical raw materials. This creates a need for the search for alternative sources of phosphate such as wastewater, since most of the phosphate we use end up in our wastewater. Additionally, the direct discharge of wastewater with high concentration of phosphorus (typically > 50 ppb phosphorus) creates a range of environmental problems such as eutrophication . In this context, the Dutch start-up company, SusPhos, created a process to produce biobased flame retardants using phosphorus recovered from municipal wastewater. Flame retardants are often used in textiles, furniture, electronics, construction materials, to mention a few. They are important for safety reasons since they can help prevent or spread fires. Currently, almost all the phosphate flame retardants in the market are obtained from phosphate rocks, but SusPhos is changing this paradigm by being the first company to produce phosphate flame retardants from waste. The process developed by SusPhos to upcycle phosphate-rich streams to high-quality flame retardant can be considered to be in the TRL 5. The company seeks to move further to a TRL 7 via building and operating a demo-scale plant in 2021/2022. BioFlame proposes a collaboration between a SME (SusPhos), a ZZP (Willem Schipper Consultancy) and HBO institute group (Water Technology, NHL Stenden) to expand the available expertise and generate the necessary infrastructure to tackle this transition challenge.