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.

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10 Jaar Triade: een evaluatie...
Wagelmans, M. ; Derksen, A. ; Lud, D. ; Mesman, M. ; Faber, J.H. - \ 2010
Bodem 20 (2010)2. - ISSN 0925-1650 - p. 18 - 20.
bodemverontreiniging - methodologie - toxicologie - onderzoek - kwaliteitsnormen - bodemecologie - ecologische risicoschatting - soil pollution - methodology - toxicology - research - quality standards - soil ecology - ecological risk assessment
Sinds 1998 wordt de Triade gebruikt voor het schatten van locatiespecifieke ecologische risico's van bodemverontreiniging. In 2008 en 2009 is een proces-NEN ontwikkels voor ecologische risicobeoordeling. Ter ondersteuning hiervan is een evaluatie uitgevoerd van all in Nederland uitgevoerde Triade projecten.
10 years of terrestrial ecological risk assessment: An evaluation
Wagelmans, M. ; Derksen, A. ; Mesman, M. ; Lud, D. ; Faber, J.H. - \ 2009
Ecologische effecten van metaalverontreiniging in het overstromingsgebied van de Dommel. Triade onderzoek, ecologische risico's en mogelijkheden voor inrichting en beheer
Derksen, J.G.M. ; Lahr, J. ; Kort, T. de; Tuin, T. ; Postma, J.F. ; Klok, T.C. ; Brink, N.W. van den; Lange, H.J. de; Kools, S.A.E. ; Hout, A. van der; Harmsen, J. ; Faber, J.H. - \ 2008
Amsterdam : Grontmij/AquaSense, Alterra & Grontmij - 81
overstromingsgebieden - bodemverontreiniging - cadmium - zink - rivieren - lichte-matig zware kleigronden - toxicologie - ecologie - nederland - natuurbeheer - kempen - noord-brabant - bottomlands - soil pollution - cadmium - zinc - rivers - clay loam soils - toxicology - ecology - netherlands - nature management - kempen - noord-brabant
De rivier de Dommel is sterk verontreinigd met cadmium en zink als gevolg van historische activiteiten van de zinkindustrie. Bij overstroming worden deze metalen, gebonden aan organisch stof en kleideeltjes, afgezet op de bodem in het overstromingsgebied. Als gevolg hiervan is ook het overstromingsgebied van de Dommel plaatselijk sterk verontreinigd. De overheid heeft voor een belangrijk deel van het Dommeldal natuurdoelstellingen opgesteld, waaronder het realiseren van de Ecologische Hoofd Structuur. Onduidelijkheid over de invloed van de metaalverontreiniging op de ecologie en natuurontwikkeling heeft geleid tot stagnatie van grondaankopen om deze EHS te kunnen realiseren. Om deze stagnatie op te heffen heeft het projectbureau Actief Bodembeheer de Kempen nader onderzoek laten uitvoeren. Het onderzoek heeft zich gericht op de vraag wat de locatiespecifieke ecologische risico’s zijn van de cadmium- en zinkverontreinigingen bij verschillende natuur(doel)typen die in het Dommeldal aanwezig zijn of ontwikkeld gaan worden. Het betreft hier de natuur(doel)typen die zich in een gebied bevinden dat gemiddeld één of meerdere keren per tien jaar overstroomd wordt. Deze natuur(doel)typen zijn voornamelijk bloemrijk grasland, nat schraalgrasland, moeras en elzenbroekbos. Het onderzoek is stapsgewijs uitgevoerd en wordt TRIADE genoemd vanwege de drie componenten waaruit het is opgebouwd te weten chemie, toxicologie en veldmetingen
De ecopyramide : biomassa beter benutten
Derksen, J.T.P. ; Seventer, E. van; Braber, K.J. ; Liere, K.J. van; Kasteren, J.H. van; Wilt, J.G. de - \ 2008
Utrecht : InnovatieNetwerk Groene Ruimte en Agrocluster (Rapport / InnovatieNetwerk 08.2.193) - ISBN 9789050593687 - 64
duurzaamheid (durability) - energiebronnen - energie - duurzame energie - durability - energy sources - energy - sustainable energy
De Nederlandse overheid probeert duurzame ontwikkeling te vergroten. De ecopyramide is daarbij een middel. De ecopyramide is een concept waarin het gebruik van biomassa wordt geoptimaliseerd. De ecopyramide brengt in beeld welke aspecten moeten worden afgewogen bij de inzet van biomassa en in welke volgorde de producten moeten worden benut. Leidraad daarbij is het maximaal gebruik van de ordening van moleculen. Daarbij staat het gebruik van biomassa voor medicijnen en voedsel voorop, gevolgd door materialen, chemische grondstoffen, transportbrandstoffen en arbeid (elektriciteit) en tot slot warmte. Het achterliggende motief is de plicht om natuurproducten, gestolde zonne-energie, zo efficiënt mogelijk te gebruiken
Detection of conformational changes in immunoglobulin G using isothermal titration calorimetry with low molecular weight probes
Rispens, T. ; Lakemond, C.M.M. ; Derksen, N.I.L. ; Aalberse, R.C. - \ 2008
Analytical Biochemistry 380 (2008)2. - ISSN 0003-2697 - p. 303 - 309.
1-anilino-8-naphthalene sulfonate - binding-sites - fluorescence - proteins - igg - ans - stability
Proteins for therapeutic use may contain small amounts of partially misfolded monomeric precursors to postproduction aggregation. To detect these misfolded proteins in the presence of an excess of properly folded protein, fluorescent probes such as 8-anilino-1-naphthalene sulfonate (ANS) are commonly used. We investigated the possibility of using isothermal titration calorimetry (ITC) to improve the detection of this type of conformational change using hydrophobic probes. As a case study, conformational changes in human polyclonal immunoglobulin G (IgG) were monitored by measuring the enthalpies of binding of ANS using ITC. Results were compared with those using fluorescence spectroscopy. IgG heated at 63 degrees C was used as a model system for "damaged" IgG. Heat-treated IgG can be detected already at levels below 5% with both ITC and fluorescence. However, ITC allows a much wider molar probe-to-protein ratio to be sampled. In particular, using reverse titration experiments (allowing high probe-to-protein ratios not available to fluorescence spectroscopy), an increase in the number of binding sites with a K(d)>10 mM was observed for heat-treated IgG, reflecting subtle changes in structure. Both ITC and fluorescence spectroscopy showed low background signals for native IgG. The nature of the background signals was not clear from the fluorescence measurements. However, further analysis of the ITC background signals shows that a fraction (8%) binds ANS with a dissociation constant of approximately 0.2 mM. Measurements were also carried out at pH 4.5. Precipitation of IgG was induced by ANS at concentrations above 0.5 mM, interfering with the ITC measurements. Instead, with the nonfluorescent probes 4-amino-1-naphthalene sulfonate and 1-naphthalene sulfonate, no precipitation is observed. These probes yield differences in the enthalpies of binding to heated and nonheated IgG similar to ANS. The data illustrate that ITC with low-molecular-weight probes is a versatile tool to monitor conformational changes in proteins with a wider application potential than fluorescence measurements.
Biobrood van eigen bodem: een ketenproject
Postma, R. ; Bakker, A. den; Derksen, V. ; Kruiger, K. ; Maassen, J. ; Osman, A.M. ; Schepers, H.E. - \ 2008
Wageningen [etc.] : Nutriënten Management Instituut (Rapport / NMI 1136) - 30
biologische voedingsmiddelen - graanproducten - brood - landbouwplantenteelt - akkerbouw - ketenmanagement - regionale voedselketens - organic foods - cereal products - bread - crop husbandry - arable farming - supply chain management - regional food chains
In 2007 is het ketenproject “Biobrood van eigen bodem” uitgevoerd in het kader van het coinnovatieprogramma biologische afzetketens. Het betrof een samenwerkingsproject van een aantal ketenpartijen uit de biologische broodketen en een aantal kennisinstellingen. Het doel van het project was gericht op het verbeteren van het imago van biologisch brood door het verhogen van het aandeel Nederlandse tarwe, wat mogelijk een bijdrage kan leveren aan het vergroten van de afzetmogelijkheden ervan. Daartoe is een consumentenonderzoek uitgevoerd en zijn veldproeven met bemestingsvarianten uitgevoerd. Tenslotte zijn met de tarwe uit de veldproeven bakproeven uitgevoerd.
Het Buys Ballot symposium 2006
Beersma, J.J. ; Berg, W.J. van de; Derksen, J. ; Kuipers Munneke, P. ; Mathies, J. ; Overeem, A. ; Pieterse, G. ; Schroter, J.S. ; Vigano, I. ; Vis-Star, N. ; Steeneveld, G.J. - \ 2007
Meteorologica / Nederlandse Vereniging van Beroeps Meteorologen 16 (2007)1. - ISSN 0929-1504 - p. 13 - 17.
Modulation of cell wall structure and composition using a fungal cellulose-binding domain
Quentin, M.G.E. ; Indemans, M.H.G. ; Derksen, J. ; Jong, E. de; Valk, H.C.P.M. van der - \ 2004
In: Wood fibre cell walls : methods to study their formation, structure and properties / Schmitt, U., Ander, P., Barnett, J.R., Emons, A.M.C., Jeronimidis, G., Saranpää, P., Tschegg, S., Uppsala : Swedish University of Agricultural Sciences - ISBN 9157668035 - p. 45 - 56.
Two Validated HPLC Methods for the Quantification of Alizarin and other Anthraquinones in Rubia tinctorum Cultivars
Derksen, G.C.H. ; Lelyveld, G.P. ; Beek, T.A. van; Capelle, A. ; Groot, Æ. de - \ 2004
Phytochemical Analysis 15 (2004)6. - ISSN 0958-0344 - p. 397 - 406.
cell-suspension cultures - performance liquid-chromatography - madder root - morinda-citrifolia - quantitative-analysis - tissue-cultures - lucidin - hydroxyanthraquinones - growth - identification
Direct and indirect HPLC-UV methods for the quantitative determination of anthraquinones in dried madder root have been developed, validated and compared. In the direct method, madder root was extracted twice with refluxing ethanol-water. This method allowed the determination of the two major native anthraquinone glycosides lucidin primeveroside and ruberythric acid. In the indirect extraction method, the anthraquinone glycosides were first converted into aglycones by endogenous enzymes and the aglycones were subsequently extracted with tetrahydroturan-water and then analysed. In this case the anthraquinones alizarin, purpurin and nordamnacanthal may be determined. The content of nordamnacanthal is proportional to the amount of lucidin primeveroside 14 originally present. The indirect extraction method is easier to apply. Different madder cultivars were screened for their anthraquinone content. Copyright (C) 2004 John Wiley Sons, Ltd.
Verwijdering van hormoonverstorende stoffen in rwzi's
Loeffen, P. ; Lahr, J. ; Derksen, A. ; Uijterlinde, C. ; Roeleveld, P. - \ 2004
H2O : tijdschrift voor watervoorziening en afvalwaterbehandeling 37 (2004)5. - ISSN 0166-8439 - p. 19 - 21.
afvalwaterbehandeling - rioolafvalwater - hormonen - oestrogenen - waterzuivering - oppervlaktewater - waterverontreiniging - zuiveringsinstallaties - hormoonverstoorders - waste water treatment - sewage effluent - hormones - oestrogens - water treatment - surface water - water pollution - purification plants - endocrine disruptors
Door de STOWA is eind vorig jaar een literatuurstudie naar de verwijdering van hormoonverstorende stoffen (ook wel endocrine disrupting chemicals of EDC's genoemd) in rioolwaterzuiveringsinstallaties verricht. Hieruit blijkt dat, ondanks een redelijke verwijdering in de rwzi, de concentraties van bepaalde EDC's in het effluent nog steeds kunnen leiden tot biologische effecten. De grootste risico's geven de oestrogene hormonen 17a-ethinyloestradiol ('de pil'), 17beta-oestradiol en oestron en de industriële detergenten nonylfenol en nonylfenolethoxylaten. Het is onduidelijk hoe de huidige rioolwaterzuiveringsinstallaties geoptimaliseerd kunnen worden om hormoonverstorende stoffen te verwijderen. Geavanceerde technieken lijken de beste resultaten op te leveren
Cloning, characterisation and assessment of the cell wall modifying ability of a fungal cellulose-binding domain
Quentin, M.G.E. - \ 2003
Radboud University Nijmegen. Promotor(en): C. Mariani, co-promotor(en): Johan Derksen; H.C.P.M. van der Valk. - Nijmegen : Katholieke Universiteit Nijmegen - ISBN 9064642583 - 149
plantenvezels - celwanden - enzymactiviteit - bindende eiwitten - chemische samenstelling - genexpressie - arabidopsis thaliana - schimmels - cellulose - genetische modificatie - bacteriën - dierkloneren - fungi - bacteria - plant fibres - cell walls - enzyme activity - binding proteins - chemical composition - gene expression - genetic engineering - animal cloning
Chemical and enzymatic hydrolysis fo anthraquinone glycosides from madder roots
Derksen, G.C.H. ; Naayer, M. ; Beek, T.A. van; Capelle, A. ; Haaksman, I.K. ; Doren, H.A. ; Groot, Æ. de - \ 2003
Phytochemical Analysis 14 (2003)3. - ISSN 0958-0344 - p. 137 - 144.
rubia-tinctorum l - alcoholic aroma formation - tea leaves - hydroxyanthraquinones - primeverosidase - mutagenicity - genotoxicity - derivatives - extracts - lucidin
For the production of a commercially useful dye extract from madder, the glycoside ruberythric acid has to be hydrolysed to the aglycone alizarin which is the main dye component. An intrinsic problem is the simultaneous hydrolysis of the glycoside lucidin primeveroside to the unwanted mutagenic aglycone lucidin. Madder root was treated with strong acid, strong base or enzymes to convert ruberythric acid into alizarin and the anthraquinone compositions of the suspensions were analysed by HPLC. A cheap and easy method to hydrolyse ruberythric acid in madder root to alizarin without the formation of lucidin turned out to be the stirring of dried madder roots in water at room temperature for 90 min: this gave a suspension containing pseudopurpurin, munjistin, alizarin and nordamnacanthal. Native enzymes are responsible for the hydrolysis, after which lucidin is converted to nordamnacanthal by an endogenous oxidase
Analysis of anthraquinones in Rubia tinctorum L. by liquid chromatography coupled with diode-array UV and mass spectrometric detection
Derksen, G.C.H. ; Niederländer, H.A.G. ; Beek, T.A. van - \ 2002
Journal of Chromatography. A, Including electrophoresis and other separation methods 978 (2002). - ISSN 0021-9673 - p. 119 - 127.
A liquid chromatographic (LC) method for the separation of both anthraquinone glycosides and aglycones in extracts of Rubia tinctorum was improved. For on-line MS detection atmospheric pressure chemical ionisation as well as electrospray ionisation (ESI) were used. The glycosides were ionised in both positive and negative ionisation (NI) mode, the aglycones only in the NI mode. With ESI ammonia was added to the eluent post-column to deprotonate the compounds. The efficiency of mass detection of the hydroxyanthraquinone aglycones was found to depend on the pKa value of the component. LC–diode-array detection and LC–MS provide useful complementary information for the identification of anthraquinones in plant extracts, which was proven with the identification of munjistin and pseudopurpurin.
Description of a cellulose-binding domain and a linker sequence from Aspergillus fungi
Quentin, M. ; Ebbelaar, M. ; Derksen, J. ; Mariani, C. ; Valk, H. van der - \ 2002
Applied Microbiology and Biotechnology 58 (2002)5. - ISSN 0175-7598 - p. 658 - 662.
Rubia Tinctorum L.
Derksen, G.C.H. ; Beek, T.A. van - \ 2002
In: Studies in natural products chemistry / Atta-ur-Rahman Amsterdam : Elsevier - ISBN 9780444510044 - p. 629 - 684.
Method for the production of a dye preparation based on madder root
Derksen, G.C.H. ; Beek, T.A. van; Capelle, A. - \ 2001
Octrooinummer: EP1191070, verleend: 2001-09-26.
The present invention relates to a method for the production of a dye preparation from madder root, comprising extraction of madder root in water at a temperature below 70-75 DEG C, preferably below 65 DEG C, while providing oxygen to the reaction mixture of madder root in water to obtain the dye preparation and to the dye preparation thus obtained
Red, redder, madder : analysis and isolation of anthraquinones from madder roots (Rubia tinctorum)
Derksen, G.C.H. - \ 2001
Wageningen University. Promotor(en): Æ. de Groot; A. Capelle; T.A. van Beek. - S.l. : S.n. - ISBN 9789058084620 - 150
antrachinonen - rubia tinctorum - analyse - plantextracten - anthraquinones - rubia tinctorum - analysis - plant extracts

The roots of Rubia tinctorum L. (madder) are the source of a natural dye. The dye components are anthraquinones with alizarin being the main dye component. Alizarin as such is present in madder root in only small quantities, most of the alizarin is present as its glycoside ruberythric acid. The sugar in this disaccharide is primeverose. Madder roots have been used to dye textiles in many parts of the world since ancient times. From 1600-1900 there was a heavy trade in madder throughout Europe. Madder root was an important export product for Holland. In 1868 Graebe and Liebermann discovered how to prepare alizarin synthetically. At the end of the 19 thcentury the madder culture rapidly declined due to the cheaper production of synthetic alizarin. Production of synthetic alizarin gives polluting side products. Nowadays the use and production of natural dyes becomes more popular due to the growing awareness for the environment and the need for alternative crops. An important element in the revitalisation of madder as an industrial crop is that the dye preparation from madder should be able to compete in quality and price with synthetic alizarin.Due to this renewed interest this research was initiated with this thesis as result.

For the simultaneous identification of the anthraquinone glycosides and aglycones in extracts of madder root a high-pressure liquid chromatography method (HPLC) was developed. The anthraquinones were separated on an end-capped C 18 -RP column with a water-acetonitrile gradient as eluent and measured with ultra violet (UV) detection at 250 nm. For the identification of anthraquinones on-line a mass spectrometer (MS) and a diode-array detector were used.

The main anthraquinones in an ethanol-water extract of madder root are the glycosides lucidin primeveroside and ruberythric acid and the anthraquinones pseudopurpurin and munjistin, which contain a carboxylic acid moiety. Beside these compounds also small amounts of the aglycones alizarin and purpurin could be detected and sometimes also lucidin was present.

For the production of a commercially useful dye preparation from madder, the glycoside ruberythric acid should be hydrolysed to the aglycone alizarin, which is the main dye component. An intrinsic problem of the hydrolysis of ruberythric acid in madder root is the simultaneous conversion of lucidin primeveroside to the unwanted mutagenic aglycone lucidin. Madder root was treated with strong acid, strong base or enzymes to convert ruberythric acid into alizarin. The anthraquinone composition of the suspensions was analysed with HPLC-UV, HPLC-DAD and HPLC-MS.

Stirring of dried madder root in water at room temperature for 90 min gave a suspension with pseudopurpurin, munjistin, alizarin and nordamnacanthal. Nordamnacanthal originates from lucidin primeveroside, which is hydrolysed to lucidin and subsequently oxidised to the corresponding aldehyde nordamnacanthal by an endogenous hydrolase and oxidase respectively. Nordamnacanthal is not mutagenic. During this conversion oxygen is obligatory and can be added by stirring the suspension. This stirring is an easy method for simultaneously hydrolysing ruberythric acid and to getting rid of the mutagenic lucidin.

Different madder root cultivars were screened for their anthraquinone composition and amount of the main anthraquinones. The concentration of alizarin varied from 6.1 to11.8 mg/g root. If madder root was cultivated for three instead of two years the amount of alizarin increased from 6.7 mg/g to 8.7 mg/g.

A number of different methods were compared for their capacity to isolate alizarin from the rest of the plant material. To make a first selection attention was mainly paid to the yield of alizarin. Three routes were selected as most promising for an industrial application. These three methods were tested at a larger scale. The first method consisted of the following steps: conversion of madder root (250 g) by endogenous enzymes, extraction of madder root with refluxing ethanol-water, hot filtration, evaporation to half of the original volume and precipitation at 4°C. An extract of 14.7 g was obtained which consisted for 35 % of anthraquinones. Of the total amount of alizarin available in the starting material 78% was extracted. The second method consisted of the following steps: extraction of madder root (250 g) with refluxing water, hot filtration, conversion of the glycosides in the filtrate by a madder root enzyme extract and precipitation at 4°C. An extract of 3.2 g was obtained of which 38 % were anthraquinones. Of the total amount of alizarin available in the starting material 19% was extracted. The third method consisted of the following steps: extraction of madder root with an aqueous surfactant solution, twice C 18 chromatography for extracting alizarin, elution of alizarin with methanol and evaporation. An extract of 17.1 g was obtained of which 11 % were anthraquinones. Of the total amount of alizarin available in the starting material 98% was extracted.

For the development of an economically feasible route these three methods have to be further optimised. After optimisation the three routes have to be compared in terms of amount of extract obtained, alizarin content, dyeing capacity, costs and industrial applicability of the procedure.

Succes- en faalfactoren van agrificatie in Nederland
Roekel, G.J. van; Koster, A.C. ; Stijnen, D.A.J.M. ; Derksen, H. ; Fossen, M. ; Maasen, R. - \ 2000
Wageningen : ATO (ATO Rapport 607) - ISBN 9085850088 - 56
industriële gewassen - industriële toepassingen - vervangbare hulpbronnen - duurzaamheid (sustainability) - landbouwbeleid - beoordeling - kwantitatieve analyse - kwalitatieve analyse - industrial crops - industrial applications - renewable resources - sustainability - agricultural policy - assessment - quantitative analysis - qualitative analysis
Oils and fats in the food industry
Veldsink, J.W. ; Muuse, B.G. ; Derksen, J.T.P. - \ 2000
In: Raw ingredient quality in processed foods : the influence of agricultural principles and practices / Springett, M.B.,
Heat curing polymeric powder coating compositions for coating metal and other substrates have a content of unsaturated long chain fatty acid or ester to improve adhesion and appearance after baking.
Cuperus, F.P. ; German, A.L. ; Es, J.J.G.S. van; Derksen, J.T.P. ; Hamersveld, E.M.S. van - \ 1999
Octrooinummer: NL1009254, verleend: 1999-11-26.
Incorporation of unsaturated fatty acids or esters of these into polymer based powder coatings to improve adhesion and appearance after stoving. Powder coating lacquers or binders for pigmented powder coatings which comprise one or more polymers (I) and 20-80 wt. % on total weight of binder of an unsaturated fatty acid (II) or an ester of this.
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