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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A bacterium belonging to the Bacillus firmus/lentus-complex and capable of growth on native potato starch was isolated from sludge of a pilot plant unit for potato-starch production. Utilization of a crude enzyme preparation obtained from the culture fluid after growth of the microorganism on native starch, resulted in complete degradation of native starch granules from potato, maize and wheat at a temperature of 37°C. Glucose was found as a major product. Production of maltose, maltotriose and maltotetraose was also observed. Native-starch-degrading activity (NSDA) could be selectively adsorbed on potato-starch granules, whereas soluble-starch-degrading activity (SSDA) remained mainly in solution. The use of such a starch-adsorbed enzyme preparation on native starch resulted in a completely changed product pattern. An increase in oligosaccharides concomitant with less glucose formation was observed. An increased conversion of soluble starch to maltopentaose was possible with this starch-adsorbed enzyme preparation. It is concluded that NSDA comes from α-amylase(s) and SSDA from glucoamylase(s) and/or α-glucosidase(s). Cultivation of B. firmus/lentus on glucose, maltose, or soluble starch resulted in substantially smaller quantities of (native) starch-degrading activity.
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Thermal disinfection is probably the oldest water treatment method ever used. Similarly to other disinfection processes, it targets the inactivation of pathogenic (micro)organisms present in water, wastewater and other media. In this work, a pilot-scale continuous-flow thermal disinfection system was investigated using highly contaminated hospital wastewater as influent without any pre-treatment step for turbidity removal. The results proved that the tested system can be used with influent turbidity as high as 100 NTU and still provide up to log 8 microbial inactivation. Further results have shown energy consumption comparable to other commercially available thermal disinfection systems and relatively low influence on the investigated physical–chemical parameters.
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Dit projectvoorstel is gericht op de ontwikkeling van nieuwe moleculen om zelf, thuis infectieziekten te diagnosticeren. Om de diagnose van infectieziektes te bevorderen, met name in afgelegen gebieden, is de innovatieve strategie van point-of-care (POC), een snelle, accurate en sensitieve diagnostische test die door een patiënt zelf kan worden uitgevoerd, uitermate geschikt. Een simpel en klein toestel dat enzymatische activiteit uit microben kan meten is in ontwikkeling bij Enzyre B.V. Dit voorstel gaat over de ontwikkeling van nieuwe lichtgevende moleculen die de detectie van infectieziektes kunnen aantonen door middel van het Enzyre platform. Hiervoor wordt een nieuwe chemisch aanpak om dit soort lichtgevende moleculen te maken ontwikkeld. Dit is relevant voor de preventie en het monitoren controle van potentiële pandemieën zoals bijvoorbeeld de recente uitbraak van SARS-Cov-2, maar ook MERS, SARS, HIV, Ebola en meerdere influenza pandemieën uit het verleden
About 35-40 kton used mattresses available yearly for the recycling only in the Netherlands. Mattresses that are offered at recycling companies, municipal yards and retailers often find their way to incinerators. However, several fraction components of used mattresses can be reused/resale in a useful manner. One of the mattress fractions is textile cover with residue of Polyurethane (PU) foam. Effective removal of PU foam would enable further reuse of textile materials. Use of harsh chemicals/ thermo-, photo-, oxidative, processes including hydrolysis, aminolysis, phosphorolysis, glycolysis etc [1,2] for PU foam degradation is not a good solution, since it will cause non-specific damage to textiles and other parts, making recycle/ reuse difficult. Therefore, Mattress Recycling Europe BV (MRE) is looking for an eco-friendly mild process for selective degradation of PU foam component. PU is a mixed polymer; therefore, it is important to establish the physio-chemical nature of PU before identifying suitable and sustainable degradation route. The proposed solution is selective degradation of PU polymer using biotechnology. Enzymatic bio-catalysis enables a targeted, specific reaction at mild process conditions (pH, temperature) without harming other components in the process. Primarily hydrolase class of enzymes is assumed to be among the most effective options for the proposed degradation of PU foam residue [3,4]. From previous research, adding mechanical shear provides a synergistic effect for enzyme catalysed reaction [5-7]. Therefore, within the scope of this exploratory practice-oriented project, technical feasibility of bio-catalyst and shear (including well established PU degradation techniques) towards the selective degradation of PU foam residue attached to textile part from used mattresses will be explored together with cost estimation of the overall process and re-usability of enzymes using suitable immobilisation technique, addressing an urgent industrial need in the field of green chemistry.
