Waste-derived volatile fatty acids as carbon source for added-value fermentation approaches

The establishment of a sustainable circular bioeconomy requires the effective material recycling from biomass and biowaste beyond composting/fertilizer or anaerobic digestion/bioenergy. Recently, volatile fatty acids attracted much attention due to their potential application as carbon source for the microbial production of high added-value products. Their low-cost production from different types of wastes through dark fermentation is a key aspect, which will potentially lead to the sustainable production of fuels, materials or chemicals, while diminishing the waste volume. This article reviews the utilization of a volatile fatty acid platform for the microbial production of polyhydroxyalkanoates, single cell oil and omega-3 fatty acids, giving emphasis on the fermentation challenges for the efficient implementation of the bioprocess and how they were addressed. These challenges were addressed through a research project funded by the European Commission under the Horizon 2020 programme entitled 'VOLATILE-Biowaste derived volatile fatty acid platform for biopolymers, bioactive compounds and chemical building blocks'.This work was supported by the European project 'Volatile-Biowaste-derived volatile fatty acid platform for biopolymers, bioactive compounds and chemical building blocks' and has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement number 720777

Waste-derived volatile fatty acids as carbon source for added-value fermentation approaches

The establishment of a sustainable circular bioeconomy requires the effective material recycling from biomass and biowaste beyond composting/fertilizer or anaerobic digestion/bioenergy. Recently, volatile fatty acids attracted much attention due to their potential application as carbon source for the microbial production of high added-value products. Their low-cost production from different types of wastes through dark fermentation is a key aspect, which will potentially lead to the sustainable production of fuels, materials or chemicals, while diminishing the waste volume. This article reviews the utilization of a volatile fatty acid platform for the microbial production of polyhydroxyalkanoates, single cell oil and omega-3 fatty acids, giving emphasis on the fermentation challenges for the efficient implementation of the bioprocess and how they were addressed. These challenges were addressed through a research project funded by the European Commission under the Horizon 2020 programme entitled ‘VOLATILE—Biowaste derived volatile fatty acid platform for biopolymers, bioactive compounds and chemical building blocks’.This work was supported by the European project ‘VolatileBiowaste-derived volatile fatty acid platform for biopolymers, bioactive compounds and chemical building blocks’ and has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement number 720777

Feasibility of grass co-digestion in an agricultural digester, influence on process parameters and residue composition

The European Union states that by 2020, 20% of the European energy consumption should come from renewable energy. This study investigated the potential of co-digestion of grass clippings (waste) in a typical Flemish agro-digester characterized by an input of 30% manure, 30% maize silage and 40% side streams. No significant adverse effects in the microbiological functioning of the reactors were detected when 10 to 20% out of the 30% maize input was replaced by grass. However at the highest dosage of grass input, dry matter content and the viscosity of the reactor content increases substantially. These elevated parameters could subsequently be reduced again by enzyme addition in the form of MethaPlus L100, although they remained higher than those of the reference reactor receiving maize. It can be concluded that co-digestion of 20% grass in a typical agricultural digester would not pose any problem if dry matter content and viscosity are improved by the use of an enzyme mixture. This is good news for a region like Flanders, where arable land for (energy) crop production is scarce and where grass wastes remain in many cases unused

Van gras tot groen gas

Gras dat afkomstig is van wegbermen en graslandbeheer wordt vaak als een ongewenste biomassastroom beschouwd waarmee de dag van vandaag weinig gedaan wordt. Aan de andere kant zijn voor biogasproductie via vergisting vaak dure biomassastromen zoals energiemaïs nodig, welke de economische rendabiliteit van de vergistingsinstallatie onder druk zetten. Het Vlaams-Europese project Graskracht (2010-2012) testte daarom de mogelijkheid van co-vergisting van gras ter vervanging van energiemaïs

<i>HES6</i> knockdown in human hematopoietic precursor cells reduces their <i>in vivo</i> engraftment potential and their capacity to differentiate into erythroid cells, B cells, T cells and plasmacytoid dendritic cells

Hematopoiesis is driven by molecular mechanisms that induce differentiation and proliferation of hematopoietic stem cells and their progeny. This involves the activity of various transcription factors, such as members of the Hairy/Enhancer of Split (HES) family, and important roles for both HES1 and HES4 have been shown in normal and malignant hematopoiesis. Here, we investigated the role of HES6 in human hematopoiesis using in vitro and in vivo models. Using bulk and scRNA-seq data, we show that HES6 is expressed during erythroid/megakaryocyte and pDC development, as well as in multipotent precursors and at specific stages of T- and B-cell development following preBCR and preTCR signalling, respectively. Consistently, knockdown of HES6 in cord blood-derived hematopoietic precursors in well-defined in vitro differentiation assays resulted in reduced differentiation of human hematopoietic precursors towards megakaryocytes, erythrocytes, pDCs, Band T-cells. In addition, HES6 knockdown HSPCs displayed reduced colony forming unit capacity in vitro and impaired potential to reconstitute hematopoiesis in vivo in a competitive transplantation assay. We demonstrate that loss of HES6 expression impacts cell cycle progression during erythroid differentiation and provide evidence for potential downstream target genes that impact these perturbations. Thus, our study uncovers new insights for a role of HES6 in human hematopoiesis

Towards a Circular Bioeconomy. VOLATILE FATTY ACID PLATFORM FOR BIOWASTE RECYCLING

Resources in general are not infinitely available, and also renewable resources if consumed outside their normal replacement cycles become scarce. Therefore, the establishment of a circular bioeconomy must respect natural systems and replacement cycles of organic carbon thereby reducing environmental pressure of human consumption. Upcycling of side and biowaste streams towards added value compounds represents hereby a critical aspect reducing land system change and fertilizer use for biomass supply for the bioeconomy. The development of a Volatile Fatty Acids Platform (VFAP) represents an important cornerstone for the upcycling of heterogenous municipal biowaste streams.This e-book was prepared in the context of the EU funded project VOLATILE in accordance with the grant agreement No 720777 (European Union’s Horizon 2020 research and innovation programme)