Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Breeding progress and preparedness for mass-scale deployment of perennial lignocellulosic biomass crops switchgrass, miscanthus, willow and poplar
    Clifton-Brown, John ; Harfouche, Antoine ; Casler, Michael D. ; Dylan Jones, Huw ; Macalpine, William J. ; Murphy-Bokern, Donal ; Smart, Lawrence B. ; Adler, Anneli ; Ashman, Chris ; Awty-Carroll, Danny ; Bastien, Catherine ; Bopper, Sebastian ; Botnari, Vasile ; Brancourt-Hulmel, Maryse ; Chen, Zhiyong ; Clark, Lindsay V. ; Cosentino, Salvatore ; Dalton, Sue ; Davey, Chris ; Dolstra, Oene ; Donnison, Iain ; Flavell, Richard ; Greef, Joerg ; Hanley, Steve ; Hastings, Astley ; Hertzberg, Magnus ; Hsu, Tsai Wen ; Huang, Lin S. ; Iurato, Antonella ; Jensen, Elaine ; Jin, Xiaoli ; Jørgensen, Uffe ; Kiesel, Andreas ; Kim, Do Soon ; Liu, Jianxiu ; McCalmont, Jon P. ; McMahon, Bernard G. ; Mos, Michal ; Robson, Paul ; Sacks, Erik J. ; Sandu, Anatolii ; Scalici, Giovanni ; Schwarz, Kai ; Scordia, Danilo ; Shafiei, Reza ; Shield, Ian ; Slavov, Gancho ; Stanton, Brian J. ; Swaminathan, Kankshita ; Trindade, Luisa M. - \ 2019
    Global change biology Bioenergy 11 (2019)1. - ISSN 1757-1693 - p. 118 - 151.
    bioenergy - feedstocks - lignocellulose - M. sacchariflorus - M. sinensis - Miscanthus - Panicum virgatum - perennial biomass crop - Populus spp. - Salix spp.

    Genetic improvement through breeding is one of the key approaches to increasing biomass supply. This paper documents the breeding progress to date for four perennial biomass crops (PBCs) that have high output–input energy ratios: namely Panicum virgatum (switchgrass), species of the genera Miscanthus (miscanthus), Salix (willow) and Populus (poplar). For each crop, we report on the size of germplasm collections, the efforts to date to phenotype and genotype, the diversity available for breeding and on the scale of breeding work as indicated by number of attempted crosses. We also report on the development of faster and more precise breeding using molecular breeding techniques. Poplar is the model tree for genetic studies and is furthest ahead in terms of biological knowledge and genetic resources. Linkage maps, transgenesis and genome editing methods are now being used in commercially focused poplar breeding. These are in development in switchgrass, miscanthus and willow generating large genetic and phenotypic data sets requiring concomitant efforts in informatics to create summaries that can be accessed and used by practical breeders. Cultivars of switchgrass and miscanthus can be seed-based synthetic populations, semihybrids or clones. Willow and poplar cultivars are commercially deployed as clones. At local and regional level, the most advanced cultivars in each crop are at technology readiness levels which could be scaled to planting rates of thousands of hectares per year in about 5 years with existing commercial developers. Investment in further development of better cultivars is subject to current market failure and the long breeding cycles. We conclude that sustained public investment in breeding plays a key role in delivering future mass-scale deployment of PBCs.

    AQUAFARM van zuiveren naar oogsten
    Verdonschot, P.F.M. - \ 2017
    Aquafarm NL
    afvalwater - waterzuivering - industriële grondstoffen - biobased economy - afvalwaterbehandeling - aquacultuur - biomassa productie - waste water - water treatment - feedstocks - biobased economy - waste water treatment - aquaculture - biomass production
    Aquafarm ziet afvalwater als basis voor het produceren van hoogwaardige bouwstoffen, waarmee tegelijkertijd het water gezuiverd wordt.
    Microbial chain elongation based on methanol
    Chen, Wei-Shan - \ 2017
    Wageningen University. Promotor(en): C.J.N. Buisman; C. Kroeze, co-promotor(en): D.P.B.T.B. Strik. - Wageningen : Wageningen University - ISBN 9789463431989 - 201
    feedstocks - renewable resources - organic wastes - waste utilization - fermentation - methanol - industriële grondstoffen - vervangbare hulpbronnen - organisch afval - afvalhergebruik - fermentatie - methanol

    Our society relies heavily on fossil resources to fulfill our energy and commodity demands and this dependence has led to negative economic, environmental and societal consequences. The re-generation rate of fossil resources is much slower than their consumption rate, making these resources a non-renewable feedstock for the supply of energy and goods to our society. Moreover, the rapid consumption of fossil resources releases the carbon sequestrated in the last few million years in a much shorter time span, which contributes to the carbon dioxide (CO2) concentration increase in the atmosphere and potentially global warming. The geographically-uneven distribution of fossil resources also induces social insecurities and political conflicts. An alternative feedstock is necessary for energy and goods supply to our society, and such alternative feedstock should be renewable, economically sustainable, environmentally sound and geographically wide-spread,.

    Organic waste is an emerging and promising alternative feedstock. The production of organic waste is inevitable, occurs in large quantities and is geographically wide-spread, especially the so-called “mixed organic waste,” e.g. organic fraction of municipal solid waste (OFMSW) and food processing waste. Mixed organic waste contains a large quantity of carbon materials that can be valorised into energy carriers and commodities. However, the extremely heterogeneous composition and the relatively high water content of mixed organic waste make its valorisation via the current waste management methods (e.g. incineration, composting and anaerobic digestion) less efficient and not economically attractive. Given this context, a novel bioprocess based on a mixed culture fermentation, i.e. microbial chain elongation, was developed to promote the valorisation of mixed organic waste. In microbial chain elongation, the diverse, complex organic matter in mixed organic waste are homogenised via hydrolysis and bacterial acidification into basic building blocks; like short chain fatty acids (SCFAs), CO2 and hydrogen (H2). After the homogenisation, energy-rich co-substrates like ethanol are added to these basic building blocks to synthesise medium chain fatty acids (MCFAs) via a mixed culture fermentation. MCFAs are organic compounds with a higher economic value and a higher energy content. Microbial chain elongation can be operated under a non-sterile condition, which makes it applicable to valorise mixed organic waste where diverse microorganisms exist. Caproate is the most dominant product in the microbial chain elongation of mixed organic waste and ethanol, which can be produced at a high rate and selectivity. Caproate has a higher economic value, a lower solubility in water and an interesting market potential. Thus, caproic acid production from mixed organic waste and ethanol via microbial chain elongation is currently undergoing up-scaling and commercialisation.

    Many studies were done to improve the process of caproate production via microbial chain elongation to make it of industrial interest. The on-going commercialisation of microbial chain elongation also supports the economic feasibility. However, until now, no study addressed the environmental sustainability of microbial chain elongation. Chapter 2 of this thesis took the first attempt in analysing the life-cycle environmental impacts of caproic acid production from organic waste via microbial chain elongation, based on the literature and existing business case. The use of ethanol as a co-substrate (i.e. the electron donor) was shown to be the largest cause the environmental impact. This was found in in all assessed cases and all impact categories studied, and regardless of the feedstocks from which ethanol was produced. An alternative for ethanol as electron donor in microbial chain elongation is, therefore, an effective way to improve the environmental sustainability of microbial chain elongation.

    In Chapter 3, we investigated the use of methanol as an alternative electron donor in microbial chain elongation, i.e. methanol chain elongation, for butyrate and caproate production. Methanol chain elongation was previously demonstrated using a pure culture, but never with a mixed culture. To employ organic waste as feedstock, the feasibility of applying methanol chain elongation in an open mixed culture condition needs to be investigated. In Chapter 3, it was demonstrated in a batch incubation that methanol chain elongation could occur with a mixed culture, where butyrate was the dominant product (4.2 g/L). Caproate production via methanol chain elongation was also demonstrated, though only in a low concentration (0.1 g/L). In a continuous reactor operation, continuous butyrate production (1.5 g/ was achieved via microbial chain elongation of acetate and methanol. However, caproate was not observed in the continuous methanol chain elongation. Interestingly, microorganisms that can perform methanol chain elongation were likely present in the inoculum taken from a previous ethanol chain elongation reactor without any methanol supplement.

    In Chapter 4, the use of methanol chain elongation to synthesise a novel product, i.e. isobutyrate, was proposed and investigated. Methanol chain elongation was found to continuously produce butyrate as the main metabolite, the accumulation of which was found to trigger isobutyrate formation in several previous methanogenic anaerobic digestion studies. It was, therefore, hypothesised that by elevating the butyrate concentration in the medium, methanol chain elongation might be able to produce isobutyrate as another metabolite. The result showed that isobutyrate could be produced as the main product, up to 6.2 g/L, when using acidified supermarket food waste and methanol as the substrate. A continuous methanol chain elongation using synthetic medium was also performed, which achieved a production rate of 2.0 g/ over five hydraulic retention times. Moreover, the production of isovalerate was also observed. Isobutyrate has a much larger market potential than caproate, though its production relies wholly on fossil-based feedstock. Isobutyrate biosynthesis was demonstrated in previous studies, but was only achieved using metabolically engineered microorganisms as the biocatalyst and glucose as the substrate. Methanol chain elongation, in contrast, could employ derivatives from organic waste as the substrates and a self-regenerating mixed culture biocatalyst for producing isobutyrate. Moreover, methanol chain elongation may be integrated into the current microbial chain elongation production facility without a significant infrastructure retrofit. All these advantages make methanol chain elongation an interesting and promising isobutyrate production process. The relatively large market potential of isobutyrate promotes the application of chain elongation and the use of organic waste for value-added chemical production.

    In Chapter 5, isobutyrate production was integrated with the caproate production via microbial chain elongation, by concurrently feeding both methanol and ethanol to a mixed culture. The result from Chapter 3 supports the possibility of coexistence of ethanol and methanol chain elongation microorganisms in the same microbiome. In Chapter 4, the possible concurrence of methanol and ethanol chain elongation was also observed. Based on these observations, we hypothesised that methanol and ethanol chain elongation could be integrated to simultaneously produce caproate and isobutyrate. The result showed that such integration was possible when a stable pH was maintained. When pH was controlled between 6.2 – 6.5 and butyrate was supplied in the medium, caproate and isobutyrate could be produced simultaneously. Additionally, increasing the ethanol feeding rate promoted the chain elongation of butyrate to caproate via ethanol chain elongation. The outcome of this chapter demonstrated the possibility of producing two valuable products in a single reactor with a mixed culture which, coupled with further process improvement, may be of industrial interest.

    In Chapter 6, we reflected on the caproate production performance of methanol chain elongation, in comparison with other electron donors used in microbial chain elongation, i.e. ethanol and lactate. Furthermore, we also reflected on the isobutyrate production via methanol chain elongation, in comparison with other emerging products in microbial chain elongation. These reflections could serve as a benchmark for methanol chain elongation as a waste management strategy. Based on this benchmarking, we proposed that methanol chain elongation is a promising bioprocess for isobutyrate production but not for caproate production. A potential strategy for improving the isobutyrate production via methanol chain elongation was proposed and discussed. The outcomes of this thesis may contribute to future application and assessments of microbial chain elongation in waste management. It may fuel discussion on how to further promote microbial chain elongation for a more sustainable waste management.

    Stadium Coltan : artisanal mining, reforms and social change in eastern Democratic Republic of Congo
    Wakenge, Claude Iguma - \ 2017
    Wageningen University. Promotor(en): D.J.M. Hilhorst, co-promotor(en): K. Vlassenroot; J.G.R. Cuvelier. - Wageningen : Wageningen University - ISBN 9789463434560 - 210
    mining - conflict - economic sociology - cooperatives - reconstruction - poverty - rural sociology - workers - feedstocks - minerals - congo democratic republic - central africa - mijnbouw - conflict - economische sociologie - coöperaties - reconstructie - armoede - rurale sociologie - werkers - industriële grondstoffen - mineralen - democratische republiek kongo - centraal-afrika

    In the Democratic Republic of Congo (DRC), the mining sector has the potential to play a pivotal role in post-conflict reconstruction (World Bank, 2008), and artisanal mining sustains the livelihoods of millions people in the country (PACT, 2010). However, in the last 15 years, minerals from this artisanal mining have been ill-reputed. Eastern DRC has often been characterised by chronic instability and violent conflicts (Autesserre, 2010; Stearns, 2011) because it is widely believed that minerals in this region have attracted the greed of national and foreign armed groups, who benefit from the mining business.

    Although this ‘greed hypothesis’ has been criticised for its inconsistent performance in explaining resource-related conflicts (Le Billon, 2010; Ross, 2006), various national and international reform initiatives have gained momentum (Verbruggen et al., 2011). These initiatives aim to make the Congolese artisanal mining sector more transparent and to prevent ‘conflict minerals’ from entering the international market. In 2014, 13 reform initiatives—10 focusing on 3T (tantalum, tin and tungsten) and three on gold—were operational in eastern DRC (Cuvelier et al. 2014: 5). The implicit assumptions are that mining reforms will fully ‘clean’ artisanal mining of violence and corruption and that this will contribute to sustaining people’s livelihoods (Garrett and Mitchell, 2009: 12).

    This study investigated initiatives intended to ‘formalise’ artisanal mining in DRC—in other words, they aimed to bring mining under state control. The study especially focuses on the effects of one among these initiatives—the ITRI Tin Supply Chain Initiative (iTSCi)—on two groups of actors: miners (creuseurs) and middlemen (négociants). This thesis thus presents a fine-grained case study of the iTSCi. Designed by the International Tin Research Institute in 2009, iTSCi provides a means of determining the origin of 3T and documenting the trading chain for these minerals by ‘tagging and bagging’ the loads of 3T near miners’ shafts (at postes d’achat/selling points or buying stations), at counting offices (comptoirs) and in mineral depots, before the minerals are exported through the international market.

    This is a qualitative study undertaken at three coltan mining sites of northern Katanga: Kahendwa, Kisengo and Mai-Baridi. Coltan has been extracted at these sites since 2007. From March 2013 to September 2014, data were collected using participant observation of people’s practices (extraction/sale of coltan and various types of interactions between trading houses, cooperatives, mineworkers (creuseurs) and middlemen (négociants), as well as detailed in-depth interviews with creuseurs, négociants and their households. Data were also collected from the staff of mining cooperatives, trading houses, state authorities and civil servants—predominantly of the Service d’Assistance et d’Encadrement du Small-Scale Mining (SAESSCAM) and the Division des Mines. The last group of informants were a group of clandestine coltan négociants (known as hiboux—literally, ‘owls’), who were followed in the study.

    The purpose of this research is to study the micro-dynamics of changes after the reforms following the implementation of iTSCi. The study thus provides insights into how iTSCi is concretely implemented and how it has altered the organisation of mining and the trade of coltan. The study also aims to examine how this organisation affected creuseurs and négociants. The main research question of this study is as follows:

    How have initiatives to reform artisanal mining (iTSCi in particular) affected institutional change, how does this relate to changes in patterns of coltan production and trade, how were creuseurs and négociants affected by these changes, and how did these groups respond in the coltan mining areas of Kahendwa, Kisengo and Mai Baridi (northern Katanga) from 2009 to 2014?

    Analytically, the study adopted three main theoretical perspectives. First, an actor-oriented approach was taken, building on the premise that individual actors have the agency, knowledge and experience to reflect upon their situation and to respond to changes in their surrounding context (Giddens, 1984). Although the examined mining reforms consist predominantly of ‘ready-made’ techniques such as iTSCi’s ‘tagging and bagging’, analysing reforms with an actor orientation helps to highlight people’s reactions and responses. This includes how reform policies are applied in institutions (e.g. mining cooperatives), how they interact, how they are assigned meaning and how they are negotiated by social actors (Christoplos and Hilhorst, 2009).

    Second, the study builds on the sociology of economic life, which holds that economic action is a form of social action that is socially ‘embedded’, meaning that it is linked with or dependent on actions and institutions (such as social networks) that are noneconomic in content, goals and processes (Granovetter, 2005). This perspective facilitates the analysis of the livelihoods of négociants, including mechanisms of smuggling minerals into and beyond the mining areas where iTSCi is in force.

    Third, this thesis introduced the original concept of ‘enclaves of regulations’. These enclaves refer to the mining areas where iTSCi or other reforms are in force. This thesis has shown that, although these ‘enclaves’ appear to be ‘closed’ and insulated from the environment in terms of the locally applied rules for the mining and trading of minerals (e.g. ‘tagging and bagging’), in reality, such closure is not complete. This thesis has demonstrated that it would therefore be more appropriate to consider these ‘enclaves’ as semi-autonomous fields with porous boundaries.

    Apart from the introduction and the concluding chapters, this thesis is composed of five chapters. Chapter 2 explores the evolution of the mineral sector in the Katanga province. It analyses the history of mining, the initiation of artisanal mining and how the ongoing reforms have been informed by this history. In this chapter, it is shown that there is a long history of the organisation of mining in the Katangese province. The reforms therefore did not enter into a stage of anarchy, or an institutional void, but they added a layer to already existing forms of organisation.

    Chapter 3 focuses on mining cooperatives as newly introduced institutions aimed at governing the artisanal mining sites. Through a single case study, the chapter analyses how these cooperatives —especially the Coopérative des Artisanaux Miniers du Congo, CDMC—were introduced into the mining areas and how they interacted and blended with pre-existing miners’ organisations. This chapter demonstrates that cooperatives have been an emergent—rather than durable—solution in terms of representing the interests of artisanal miners.

    In Chapter 4, I provide a different perspective on ‘conflict minerals’. I thus introduce the notion of ‘reform conflicts’ to emphasise that, although ongoing reforms aim to sever the supposed linkages between the artisanal mining business and violent conflicts, these reforms have become a driving force behind the emergence of new conflicts over property rights and access to minerals.

    Chapter 5 is about livelihoods. It analyses how the reforms have influenced the livelihoods and socioeconomic position of négociants. This chapter also explores what kind of opportunities the reforms have offered to this group of mineral brokers often considered powerful in the mineral supply chain and explains what kind of constraints the négociants have confronted and why they have opted to diversify their livelihood portfolios. The chapter has shown that the reforms have affected this group of mineral brokers in different ways. Some négociants were well off, whereas others have been excluded from the mineral commodity chain. These findings contradict the widespread opinion that négociants are always abusive brokers in the mineral production and commodity chain.

    Chapter 6 analyses the responses of creuseurs and négociants to iTSCi. Although the mining sites where iTSCi is in force appear to be ‘enclaves of regulations’, I explore the strategies of creuseurs and négociants to bypass iTSCi and the reforms, especially around the coltan trade. This chapter demonstrates that coltan smuggling is a deeply rooted practice. Despite the reforms, smuggling continues in different forms.

    All of the elements highlighted above suggest that mining reforms have undergone a major shift, from addressing the initial problems associated with ‘conflict minerals’ to creating or reinforcing various types of problems, such as the influence of ‘big men’ in the mining business, coltan smuggling and the emergence of new conflicts over accessing minerals. This means that reform initiatives such as iTSCi should be based on knowledge about the actual situation. Thus, understanding and addressing these new types of problems calls for a comprehensive approach at both local and broader levels.

    Sugar beet has more to offer
    Horsman, K. ; Haveren, J. van - \ 2015
    biobased economy - sugarbeet - biomass - feedstocks - biobased materials - sugars - lignin - fibres
    Primary Food Processing : Cornerstone of plant-based food production and the bio-economy in Europe
    Logatcheva, K. ; Galen, M.A. van - \ 2015
    The Hague : LEI Wageningen UR (Report / LEI 2015-121) - 41
    primaire sector - agro-industriële ketens - landbouwindustrie - agro-industriële sector - voedselverwerking - industriële grondstoffen - biobased economy - primary sector - agro-industrial chains - agribusiness - agroindustrial sector - food processing - feedstocks - biobased economy
    This report describes the supply chains and special characteristics of plant-based primary food processors; producers of (wheat) flour, starches, vegetable oils and fats, sugar, and cocoa. The production value, direct employment in the industry, and indirect employment in farming were calculated. The significance of the plant-based primary food processing industry in terms of production value and share in the total food processing industry in the EU was estimated, and threats and opportunities were identified on the basis of desk research and interviews with PFP member organisations and companies.
    Genetics and bioenergy potential of forage maize: deconstructing the cell wall
    Torres, A.F. - \ 2014
    Wageningen University. Promotor(en): Richard Visser, co-promotor(en): Luisa Trindade; Oene Dolstra. - Wageningen : Wageningen University - ISBN 9789462570375 - 202
    zea mays - maïs - voedergewassen - plantengenetica - bio-energie - celwanden - bioethanol - bioconversie - industriële grondstoffen - brandstofgewassen - zea mays - maize - fodder crops - plant genetics - bioenergy - cell walls - bioethanol - bioconversion - feedstocks - fuel crops

    Despite gaining prominence in scientific spheres and political agendas worldwide, the production of biofuels from plant biomass is yet to achieve an economic stronghold in the renewable-energy sector. Plant lignocellulose has evolved to resist chemical and enzymatic deconstruction, and its conversion into liquid fuels requires energetically stringent processes that currently render the industry economically and environmentally unviable.

    To address this challenge, experts have envisioned the development of advanced bioenergy crops which require lower energetic and chemical inputs for their effective fractionation. At its core, this approach requires an in-depth understanding of the composition, synthesis and breeding amenability of the plant cell wall; the principal constituent of total plant dry biomass and the most recalcitrant fraction of the crop at physiological maturity to deconstruction. To this end, the primary aim of this thesis was to dissect and elucidate the biochemical and genetic factors controlling cell wall characteristics relevant to the development of bioenergy grasses with improved processing quality for cellulosic based fuel production. A focus on maize was warranted as it currently represents the de facto model system for bioenergy crop research; offering an unrivalled platform to underpin the complex genetic architecture of cell wall biosynthesis, develop advanced bioenergy-crop breeding strategies and translate cell wall research into innovations and commercial products.

    This thesis exposed that the biomass-to-fuel conversion of crops is a highly complex trait dependent on both, the balance and synergy between multiple cell wall components, and the inherent effectiveness of the conversion technology. Concerning the production of cellulosic ethanol via the combined operations of dilute-acid pretreatment and enzymatic saccharification, our results revealed that the chemical mechanisms affecting biomass conversion efficiency depend on pretreatment severity. Whereas at harsh pretreatments biomass conversion efficiency was primarily influenced by the inherent efficacy of thermochemical cell wall deconstruction, at milder pretreatments, maximum fermentable glucose release was observed for maize genotypes exhibiting systematic cell wall changes leading to higher ruminal cell wall digestibility. These results confirmed that the selection and use of cellulosic feedstocks that best match the processing conditions used in the industry can aid in reaching industrial goals aimed at improving the commercial and environmental performance of cellulosic fuels.

    In turn, the exhaustive characterization of a forage maize doubled haploid (DH) population demonstrated the vast degree of genetic diversity in maize cell wall composition and bioconversion potential amenable to breeding. Principally, these findings suggest that natural diversity in the biochemical composition of the maize cell wall and its physical properties is primarily ascribed to variation in the balance, monomeric make-up, and extent of cross-linking of non-cellulosic cell wall polymers (i.e. lignin and hemicellulose). Indeed, correlation analyses confirmed that the extent of enzymatic depolymerization of maize biomass was strongly and negatively associated to the concentration of cell wall phenolics, but positively impacted by the degree of glucuronoarabinoxylan (GAX) glycosylation and extent of hemicellulose-to-hemicellulose cross-linking. Our results also showed that natural variation in cell wall content and composition is quantitatively inherited and putatively ascribed to the segregation of multiple genetic loci with minor additive effects. In our population, genotypic diversity for cell wall composition and quality was found to be controlled by 52 quantitative trait loci (QTLs). From eight QTLs regulating bioconversion properties, five were previously unidentified and warrant further investigation.

    Despite the apparent complexity of cell wall genetics, however, the high heritability and environmentally stability of cell wall compositional and degradability properties guarantee high selection efficacy during the development of superior DH/inbred material, and predispose that multi-environment testing will only be necessary at advanced stages of bioenergy-maize breeding programs. Moreover, because genetic variation for complex cell wall characteristics appears to be predominantly additive, preliminary selection at the inbred level will expectedly lead to successful hybrid selection; thereby minimizing the need for recurrent test-crossing procedures and evaluations. In this regard, maize cell wall bioconversion efficiency constitutes an excellent selection criterion for immediate application in modern maize breeding programs.

    Ultimately, the convergence of classical selection schemes with inexpensive genotyping, advanced biometric models, high-throughput cell wall phenotyping and doubled haploid (DH) production technologies can accelerate development and commercial release of maize cultivars for bioenergy applications. To play a determinant role in the development and realization of sustainable and cost-effective cellulosic fuel processing technologies, however, novel dual-purpose maize cultivars (i.e. delivering both, grain for feed or food and fiber materials for bioconversion) will have to surpass the performance in lignocellulose processing quality and biomass yields of the best elite germplasm. These prospects seem realistic as the parallel advance of grain yield and stover productivity and quality characteristics is a feasible undertaking. Conceptually, the advance of superior bioenergy cultivars (surpassing the performance of modern elite material) would allow us to make the currently available biomass-to-fuel conversion systems more cost-effective and sustainable, and may also have favorable consequences for the ideal size and geographical distribution of biofuel refineries.

    Suiker als grondstof voor de Nederlandse chemische industrie; Gewassen, processen, beleid
    Harmsen, P.F.H. ; Lips, S.J.J. ; Bos, H.L. ; Smit, B. ; Berkum, S. van; Helming, J. ; Jongeneel, R. - \ 2014
    Wageningen : FBR Wageningen (Rapport / Wageningen UR Food & Biobased Research 1494)
    industriële grondstoffen - chemicaliën uit biologische grondstoffen - chemische industrie - suikergewassen - biobased economy - feedstocks - biobased chemicals - chemical industry - sugar crops - biobased economy
    Suiker speelt een belangrijke rol in de biobased economy. Voor de chemische industrie kan suiker als vervanging dienen van fossiele grondstoffen voor de productie van chemicaliën en materialen zoals bioplastics. Door zeer veel partijen wordt er momenteel gewerkt aan de verdere ontwikkeling van een scala aan chemicaliën en materialen uit suikers. Dit rapport bestaat uit 2 delen: deel 1 beschrijft de potentiele vraag naar suikers voor de chemie, deel 2 beschrijft de bedrijfseconomische aspecten.
    The cellulose resource matrix
    Keijsers, E.R.P. ; Yilmaz, G. ; Dam, J.E.G. van - \ 2013
    Carbohydrate Polymers 93 (2013)1. - ISSN 0144-8617 - p. 9 - 21.
    plant fibers - biofuels - biorefinery - feedstocks - chemistry - ethanol - biomass - systems
    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where large scale competition can be expected and already is observed for the traditional industries such as the paper industry. Cellulose and lignocellulosic raw materials (like wood and non-wood fibre crops) are being utilised in many industrial sectors. Due to the initiated transition towards biobased economy, these raw materials are intensively investigated also for new applications such as 2nd generation biofuels and 'green' chemicals and materials production (Clark, 2007; Lange, 2007; Petrus & Noordermeer, 2006; Ragauskas et al., 2006; Regalbuto, 2009). As lignocellulosic raw materials are available in variable quantities and qualities, unnecessary competition can be avoided via the choice of suitable raw materials for a target application. For example, utilisation of cellulose as carbohydrate source for ethanol production (Kabir Kazi et al., 2010) avoids the discussed competition with easier digestible carbohydrates (sugars, starch) deprived from the food supply chain. Also for cellulose use as a biopolymer several different competing markets can be distinguished. It is clear that these applications and markets will be influenced by large volume shifts. The world will have to reckon with the increase of competition and feedstock shortage (land use/biodiversity) (van Dam, de Klerk-Engels, Struik, & Rabbinge, 2005). It is of interest - in the context of sustainable development of the bioeconomy - to categorize the already available and emerging lignocellulosic resources in a matrix structure. When composing such "cellulose resource matrix" attention should be given to the quality aspects as well as to the available quantities and practical possibilities of processing the feedstock and the performance in the end-application. The cellulose resource matrix should become a practical tool for stakeholders to make choices regarding raw materials, process or market. Although there is a vast amount of scientific and economic information available on cellulose and lignocellulosic resources, the accessibility for the interested layman or entrepreneur is very difficult and the relevance of the numerous details in the larger context is limited. Translation of science to practical accessible information with modern data management and data integration tools is a challenge. Therefore, a detailed matrix structure was composed in which the different elements or entries of the matrix were identified and a tentative rough set up was made. The inventory includes current commodities and new cellulose containing and raw materials as well as exotic sources and specialties. Important chemical and physical properties of the different raw materials were identified for the use in processes and products. When available, the market data such as price and availability were recorded. Established and innovative cellulose extraction and refining processes were reviewed. The demands on the raw material for suitable processing were collected. Processing parameters known to affect the cellulose properties were listed. Current and expected emerging markets were surveyed as well as their different demands on cellulose raw materials and processes. The setting up of the cellulose matrix as a practical tool requires two steps Firstly, the reduction of the needed data by clustering of the characteristics of raw materials, processes and markets and secondly, the building of a database that can provide the answers to the questions from stakeholders with an indicative character. This paper describes the steps taken to achieve the defined clusters of most relevant and characteristic properties. These data can be expanded where required. More detailed specification can be obtained from the background literature and handbooks. Where gaps of information are identified, the research questions can be defined that will require further investigation. (C) 2012 Elsevier Ltd. All rights reserved.
    Biomassahubs in de regio Emmen - Coevorden
    Smakman, G.J.J. ; Annevelink, E. - \ 2013
    Lelystad : PPO-AGV - ACRRES - 58
    logistiek - biomassa - biomassa cascadering - karteringen - terminalfaciliteiten - regionale ontwikkeling - haalbaarheidsstudies - industriële grondstoffen - ketenmanagement - biobased economy - drenthe - logistics - biomass - biomass cascading - surveys - terminal facilities - regional development - feasibility studies - feedstocks - supply chain management - biobased economy - drenthe
    Doelstelling van deze verkenning is om aan te geven welke kansen er liggen voor een of meerdere biomassahubs, hoe deze eruit zouden kunnen zien en op welke manier deze zouden kunnen bijdragen aan het tot stand komen van regionale activiteiten op het gebied van de biobased economy. De biomassahub verbindt de leveranciers van biogene grondstoffen met de verwerkende industrie, door deze grondstoffen aan te leveren op een manier dat de industrie ze rechtstreeks en op een efficiënte manier kan toepassen in hun halffabricaten of eindproducten. De biomassahub kent verschillende uitvoeringsvormen, afhankelijk van de vraag en aanbod van biogene producten. Een belangrijk kenmerk van de biomassahub is de mogelijkheid om door middel van raffinagetechnieken ruwe grondstoffen te splitsen in componenten en deze allemaal een nuttige toepassing te bieden, waardoor (vrijwel) geen onbruikbare restproducten meer voorkomen.
    Traceerbaarheid van grondstoffen in voedingsmiddelen
    Spiegel, M. van der; Roest, J.G. van der; Veer, J.C. van der; Kok, E.J. - \ 2013
    Voeding Nu 3/4 (2013). - ISSN 1389-7608 - p. 12 - 13.
    voedselsamenstelling - vleeswaren - naspeurbaarheid - analytische methoden - industriële grondstoffen - voedselveiligheid - food composition - meat products - traceability - analytical methods - feedstocks - food safety
    Recente incidenten met paardenvlees in voedingsmiddelen laten zien dat bij het etiketteren van complexe voedingsmiddelen, zoals lasagne, fouten worden gemaakt. Juiste informatie over de aard van grondstoffen in voedingsmiddelen is echter van belang voor de keuzevrijheid van consumenten. Dit geldt vooral voor consumenten met specifieke dieetwensen vanwege bijvoorbeeld allergieën, religie, vegetarisme, of de wens om duurzame producten te produceren en consumeren. Kennis van de samenstelling van het product is nodig om fraude te kunnen opsporen.
    Food commodities from microalgae
    Draaisma, R.B. ; Wijffels, R.H. ; Slegers, P.M. ; Brentner, L.B. ; Roy, A. ; Barbosa, M.J. - \ 2013
    Current Opinion in Biotechnology 24 (2013)2. - ISSN 0958-1669 - p. 169 - 177.
    nitrogen starvation - biofuel production - biodiesel - oil - light - feedstocks - economics - protein - impact - algae
    The prospect of sustainable production of food ingredients from photoautotrophic microalgae was reviewed. Clearly, there is scope for microalgal oils to replace functions of major vegetable oils, and in addition to deliver health benefits to food products. Furthermore, with a limited production surface, a substantial portion of the European Union market could be supplied with edible oils and proteins from microalgae. Yet, before microalgal ingredients can become genuinely sustainable and cost effective alternatives for current food commodities, major breakthroughs in production technology and in biorefinery approaches are required. Moreover, before market introduction, evidence on safety of novel microalgal ingredients, is needed. In general, we conclude that microalgae have a great potential as a sustainable feedstock for food commodities.
    Renewable linear alpha olefins by selective ethenolysis of decarboxylated fatty acids
    Klis, F. van der; Notre, J.E.L. le; Blaauw, R. ; Haveren, J. van; Es, D.S. van - \ 2012
    European Journal of Lipid Science and Technology 114 (2012)8. - ISSN 1438-7697 - p. 911 - 918.
    productive catalyst turnovers - metathesis catalysts - cross-metathesis - methyl oleate - natural oils - dimethyl carbonate - high conversion - diesel fuel - deoxygenation - feedstocks
    A two-step concept for the production of linear alpha olefins from biomass is reported. As a starting material an internally unsaturated C17 alkene was used, which was obtained by the decarboxylation of oleic acid. Here, we report on the ethenolysis of this bio-based product, using commercially available metathesis catalysts. The desired alpha olefin products, 1-nonene and 1-decene, were obtained in excellent yield (96%) and selectivity (96%). Practical applications: The two-step conversion described in this contribution, starting from unsaturated fatty acids, provides a method for the production of industrially important linear alpha olefins. These valuable products are widely used as starting materials for the production of surfactants and polymers such as linear low density polyethylene (LLDPE).
    Growth of oil accumulating microalga Neochloris oleoabundans under alkaline-saline conditions
    Santos, A.M. ; Janssen, M.G.J. ; Lamers, P.P. ; Evers, W.A.C. ; Wijffels, R.H. - \ 2012
    Bioresource Technology 104 (2012). - ISSN 0960-8524 - p. 593 - 599.
    carbon-dioxide - flue-gas - biomass - photobioreactor - feedstocks - metabolism - economics - biodiesel - biofuels
    The effect of elevated pH and salt concentration on the growth of the freshwater microalga Neochloris oleoabundans was investigated. A study was conducted in 24-well plates on the design of a growth medium and subsequently applied in a photobioreactor. An artificial seawater medium with reduced Ca(2+) and PO(4)(3-) could prevent mineral precipitation at high pH levels. Growth was characterized in this new medium at pH8.1 and at pH10.0, with 420mM of total salts. Specific growth rates of 0.08h(-1) at pH8.1 and 0.04h(-1) at pH10.0 were obtained under controlled turbidostat cultivation. The effect of nitrogen starvation on lipid accumulation was also investigated. Fatty acids content increased not only with nitrogen limitation but also with a pH increase (up to 35% in the dry biomass). Fluorescence microscopy gave visual proof that N. oleoabundans accumulates oil bodies when growing in saline conditions at high pH.
    Cellulose, een eindeloze bron van mogelijkheden
    Keijsers, E.R.P. ; Dam, J.E.G. van; Yilmaz, G. - \ 2011
    Wageningen : Wageningen UR - Food & Biobased Research (Rapport / Food & Biobased Research nr. 1274) - ISBN 9789461730787 - 35
    chemie op basis van biologische grondstoffen - cellulose - biobrandstoffen - biobased economy - economische ontwikkeling - industriële grondstoffen - chemische industrie - marktonderzoek - biobased chemistry - cellulose - biofuels - biobased economy - economic development - feedstocks - chemical industry - market research
    Vanwege de grote diversiteit van potentiële cellulose bronnen en de grote verschillen in kwalitatieve eigenschappen en samenstelling van deze cellulose types is het van belang in kaart te brengen voor welke toepassingen de verschillende grondstoffen het meest geschikt zijn. Voor het opstellen van een dergelijke “cellulose matrix” dient aandacht te zijn voor de kwalitatieve aspecten van de grondstof alsook voor de kwantitative beschikbaarheid en praktische verwerkbaarheid van de grondstof in de applicatie. WUR-FBR heeft tijdens deze initiële studie een gedetailleerde matrix opgesteld, waarbij de verschillende componenten van de matrix zijn geïdentificeerd en een eerste invulling van de matrix is opgezet.
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