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Medium-chain-length poly-3-(R)-hydroxyalkanoates (mcl-PHAs) belong to the group of microbial polyesters. The minimum gene-set for the accumulation of mcl-PHAs from de novo fatty acid biosynthesis has been identified in prokaryotes [B. Rehm et al. (1998) J. Biol Chem 273:24044–24051] as consisting of the Pha-C1 polymerase and the ACP-CoA-transacylase. In this paper, the synthesis of mcl-PHAs has been attempted in transgenic potato (Solanum tuberosum L.) using the same set of genes that were introduced into potato by particle bombardment. Polymer contents of transgenic lines were analysed by gas chromatography and by a new simple method employing a size-exclusion filter column. The expression of the Pha-C1 polymerase and the ACP-CoA-transacylase in the plastids of transgenic potato led to the synthesis of a hydrophobic polymer composed of mcl-hydroxy-fatty acids with carbon chain lengths ranging from C-6 to C-12 in leaves of the selected transgenic lines. We strongly suggest that the polymer observed consists of mcl-PHAs and that this report establishes for the first time a possible route for the production of mcl-PHAs from de novo fatty acid biosynthesis in plants.

Water-soluble and native potato starches were modified with 1, 2, 3, 4-diepoxybutane (DEB) or 1, 2, 7, 8-diepoxyoctane (DEO). Optimal reaction conditions and the effectiveness of the cross-linkers were determined on the basis of yields of water-soluble and insoluble material. The presence of the introduced groups was confirmed by NMR spectroscopy in solution as well as in solid state. According to multi-angle laser light-scattering method, the weight average molecular masses of the water-soluble fractions prepared from water-soluble starch were larger (M-w = 471 kDa using DEB; M-w = 931 kDa with DEO) in comparison with the starting material (Mw = 291 kDa). Due to high molecular mass only new anomeric signals were observed by H-1 NMR in solution. Maximal yields of insoluble parts were 18 or 50% for DEB or DEO. On native starch the yields of insoluble products decreased with increasing concentration of cross-linker and NaOH in comparison to unmodified material. Solubilized components were dialyzed and we suppose that starch was degraded under these conditions. This material is not suitable for the modification when the goal is to increase the yield of insoluble part. With water-soluble starch the initial first order rate constants of cross-linking with E, DEB and DEO were determined with rheometer. From the relation of complex shear modulus and time by linear regression method at 20-70 degreesC, first-order rate constants of the same order of magnitude were calculated. The corresponding activation energies of the process are decreasing in the order: E (131 kJ/mol) > DEO (105 kJ/mol) > DEB (55 kJ/mol). We consider these results in agreement with the differences in the structure of the cross-linkers and the mechanism of cross-linking. Both crosslinkers gave spherical particles when cross-linked by the water-in-oil emulsion method with dimensions 60-610 (10% less than or equal to 192; 50% less than or equal to 294; 90% less than or equal to 425) mum, when cross-linked with DEB or 250-730 (10% less than or equal to 278; 50% less than or equal to 392; 90% less than or equal to 548) mum, when DEO was used. (C) 2003 Elsevier Ltd. All rights reserved.

Dit boekje heeft als doel een overzicht te schetsen over nieuwe composteerbare verpakkingsmaterialen. Het boekje is geschreven voor een breed publiek. Het boekje gaat in eerste instantie in op onderwerpen als: (1) wanneer is een materiaal composteerbaar en hoe is dat te zien, (2) milieubelasting van composteerbare materialen en (3) de wet en regelgeving rondom composteerbare producten. Vervolgens wordt meer materiaal technisch aandacht besteed aan de nieuwe composteerbare materialen die geschikt zijn om in te zetten als materiaal voor voedselverpakkingen. Daarbij wordt per materiaal ingegaan op specifieke aspecten wat betreft de herkomst, verwerking en beschikbaarheid. Tevens zal wordt ingegaan op specifieke eigenschappen en huidige toepassingsgebieden in het algemeen en als verpakkingsmateriaal in het bijzonder.

Lignin is one of the most abundant renewable raw materials available on earth. Despite its unique characteristics as a natural product with multiple chemical and biophysical functionalities, it is largely under-exploited because of its image as low quality and low added value material. Also a complete lack of any organised professional co-ordination and communication tools explicitly dedicated to lignin market promotion is one of the major drawbacks for the further development of commercial applications for lignin. As remedy, the thematic multi-partner network called EUROLIGNIN has been started in August 2002 till July 2005 with financial support of the European Commission. The major goal of this project is accelerated introduction of sustainable, high-value, lignin-based raw materials derived from leftovers in pulp and paper, and biomass processes to industry and consumers. This will be accomplished by compilation of fundamental information packages on existing and future lignin production and utilisation to create defined actions in research projects and technology activities that very precisely and with direct economic implications show the way to increased use of lignin. EUROLIGNIN consists of 26 participants including lignin producers, research centres, universities and lignin end users from 16 European countries resulting in a well-balanced consortium. (C) 2004 Elsevier B.V. All rights reserved.

Coconuts are abundantly growing in coastal areas of tropical countries. The coconut husk is available in large quantities as residue from coconut production in many areas, which is yielding the coarse coir fibre. The husk comprises ca. 30 wt.% coir fibres and 70 wt.% pith. Both fibre and pith are extremely high in lignin and phenolic content. The lignin is typically for monocotyledonous plants rich in syringyl with appreciable amounts of p-hydroxyphenyl units. The coir fibre is composed for at least one third of Mason lignin while lower molecular weight phenolics can be found as extractives in considerable amounts, especially in uounger nuts. The thermal behaviour of the original (chemically unmodified) lignin in the plant tissues at temperatures above 140degreesC, where it melts and shows thermosetting properties, has been investigated. This property,of, the coconut husk lignin was explored for application as intrinsic resin in board production, utilising whole fresh husks. Based on this concept, a simple and efficient technology has been developed to produce high strength-high density panels, without addition of chemical binders. Technical details will be reported in following papers. (C) 2003 Elsevier B.V. All rights reserved.

Inulin (general formulas GF(n) and F-m with G = anhydroglucose and F = anhydrofructose) naturally occurs as a homologous series of oligo- and polysaccharides with different chain lengths. For reasons of growing interest in the food and pet food industries, the short chain inulins have to be separated from their long chain analogues because their properties (digestibility, prebiotic activity and health promoting potential, caloric value, sweetening power, water binding capacity, etc.) differ substantially. To study these properties in relation to the number average degree of polymerization (DPn), ultrafiltration, specific crystallization from aqueous solution, and precipitation from solvent/water mixtures were used to enrich native chicory and dahlia inulin in the higher molecular weight fractions. Depending on the membrane module used, the DPn of chicory inulin (DPn = 8.1) and dahlia inulin (DPn = 29) could be increased by ultrafiltration to a maximum value of, respectively, 22 and 43. With crystallization from aqueous solutions (25 degreesC), similar results were obtained but at a much higher yield. Finally, long chain inulin could be precipitated from aqueous solutions in the presence of high concentrations of methanol, ethanol, and acetone. Acetone demonstrated to be the best solvent system to increase the DPn, followed by ethanol and methanol. However, for safety reasons and food purposes, ethanol was evaluated to be the best choice. With ethanol, the DPn could be raised to 25 for chicory inulin and up to 40 for dahlia inulin.

Wouter Elbersen is op ATO de man van het switchgrass (Panicum Virgatum L.), een gras dat voor tien à vijftien jaar wordt ingezaaid, nauwelijks bodembewerking behoeft, en dat laagwaardige vezel en / of energie levert. Een verkenning naar de mogelijkheden voor een multifunctioneel gewas

De Nederlandse regering heeft zich tot doel gesteld de administratieve lasten van ondernemersdrastisch te verlagen. Eén van de middelen daarbij is het beter gebruik maken vaninformatica- en communicatietechnologie, en het daarmee beter aansluiten op de bedrijfsprocessenvan ondernemingen. In opdracht van het Ministerie van LNV heeft een groeponderzoekers van Wageningen UR nagegaan of en hoe het centraal stellen van de ondernemerbij kan dragen aan de vermindering van administratieve lasten. Dit rapport beschrijftin een essay en negen wetenschappelijke hoofdstukken welke mogelijkheden en valkuilener zijn. Gepleit wordt voor een publiek-private samenwerking rond dit thema.

Wouter Elbersen is op ATO de man van het switchgrass (Panicum Virgatum L.), een gras dat voor tien à vijftien jaar wordt ingezaaid, nauwelijks bodembewerking behoeft, en dat laagwaardige vezel en / of energie levert. Een verkenning naar de mogelijkheden voor een multifunctioneel gewas

Dit boekje heeft als doel een overzicht te schetsen over nieuwe composteerbare verpakkingsmaterialen. Het boekje is geschreven voor een breed publiek. Het boekje gaat in eerste instantie in op onderwerpen als: (1) wanneer is een materiaal composteerbaar en hoe is dat te zien, (2) milieubelasting van composteerbare materialen en (3) de wet en regelgeving rondom composteerbare producten. Vervolgens wordt meer materiaal technisch aandacht besteed aan de nieuwe composteerbare materialen die geschikt zijn om in te zetten als materiaal voor voedselverpakkingen. Daarbij wordt per materiaal ingegaan op specifieke aspecten wat betreft de herkomst, verwerking en beschikbaarheid. Tevens zal wordt ingegaan op specifieke eigenschappen en huidige toepassingsgebieden in het algemeen en als verpakkingsmateriaal in het bijzonder.

Docosahexaenoic acid (DHA) is a polyunsaturated fatty acid composed of 22 carbon atoms and six double bonds. Because the first double bond, as counted from the methyl terminus, is at position three, DHA belongs to the so-called omega-3 group. In recent years, DHA has attracted much attention because of its beneficial effect on human health. At present, fish oil is the major source of DHA, but alternatively it may be produced by use of microorganisms. Marine microorganisms may contain large quantities of DHA and are considered a potential source of this important fatty acid. Some of these organisms can be grown heterotrophically on organic substrates without light. These processes can be well controlled and DHA with constant quality can be produced all year round. This paper reviews recent advances in the biotechnological production of DHA by marine microorganisms.

Coconuts are typically growing in coastal areas of tropical countries. The husk is abundantly available as cheap residue from coconut production in many areas, which is known to yield the coarse coir fibre. In this project a simple and efficient technology has been developed to produce high strength-high density board materials from whole coconut husks, without the addition of chemical binders. The board exhibits excellent properties, which are comparable with or even superior to commercial wood based panels. The pressed coconut husk boards can be handled with common wood working equipment for drilling and sawing, planing and polishing. Screwing, however, is only possible after pre-drilling and the board product is too hard for nailing. (C) 2004 Elsevier B.V. All rights reserved.

As part of a broader technical and economic feasibility study, we studied production of bioethanol from two types of lignocellulosic biomass by way of concentrated acid impregnation at low temperature. Willow chips and switchgrass were submitted to various impregnation techniques with concentrated sulfuric acid at varying acid: biomass ratios and impregnation times. Goal of the experiments was to investigate the technical feasibility of concentrated acid pretreatment technology as part of an industrial process that employs recycling of acid through biological means. Experimental results showed that significant amounts of fermentable sugars including glucose (up to 78 f max. obtainable glucose) and xylose can be obtained by relatively simple impregnation techniques at room temperature. Fermentation of willow-derived hydrolysates with S. Cerevisiae yielded 0.45 - 0.49 g ethanol/g glucose. Ethanol production rates however were 38 ower compared to standard glucose fermentation, prompting the need for further optimization to reduce the formation of acetic acid and furfural, two fermentation inhibitors. Novel impregnation techniques, including employment of sulfur trioxide, were also investigated but require more work to assess technical feasibility

As part of a broader technical and economic feasibility study, we studied production of bioethanol from two types of lignocellulosic biomass by way of concentrated acid impregnation at low temperature. Willow chips and switchgrass were submitted to various impregnation techniques with concentrated sulfuric acid at varying acid: biomass ratios and impregnation times. Goal of the experiments was to investigate the technical feasibility of concentrated acid pretreatment technology as part of an industrial process that employs recycling of acid through biological means. Experimental results showed that significant amounts of fermentable sugars including glucose (up to 78 f max. obtainable glucose) and xylose can be obtained by relatively simple impregnation techniques at room temperature. Fermentation of willow-derived hydrolysates with S. Cerevisiae yielded 0.45 - 0.49 g ethanol/g glucose. Ethanol production rates however were 38 ower compared to standard glucose fermentation, prompting the need for further optimization to reduce the formation of acetic acid and furfural, two fermentation inhibitors. Novel impregnation techniques, including employment of sulfur trioxide, were also investigated but require more work to assess technical feasibility

Macromolecular degradation of starch by heating and shear forces was investigated using a newly developed shear cell. With this equipment, waxy corn starch was subjected to a variety of heat and shear treatments in order to find the key parameter determining the degree of macromolecular degradation. A model based on the maximal shear stress during the treatment gave an improved prediction compared to existing models in literature based on specific mechanical energy input (SME) or shear stress multiplied by time (tau(.)t). It was concluded that molecular weight reduction of starch at the temperatures investigated (85-110degreesC) is a time-independent process, during which the starch molecules are broken down virtually instantaneously by high shear force within time scales investigated. Consequences for design of shear based processes (especially extrusion) are shortly discussed. (C) 2003 Elsevier Ltd. All rights reserved.

Sweet sorghum cultivation was carried out in South-west Greece. The fresh biomass yield was about 126 t/ha. Stalks weight accounts for 82% of total crop weight while leaves and panicle account for 17% and 1%, respectively. The major components in variety 'Keller' stalks were, based on dry weight, sugars (45%), (hemi)cellulose (35%), lignin (9%) and ash (3%). This means that per hectare, 14.5 ton sugars is produced for hydrogen fermentation. Hydrogen fermentations by the extreme thermophilic bacterium, Caldicellulosiruptor saccharolyticus, using sweet sorghum juice as carbon and energy substrate showed that it is an excellent substrate with a H2 yield of 58% of the theoretical maximum at a maximal production rate of 21 mmol/L.h. Besides the sugary juice, 15 ton/ha bagasse (dry weight) is obtained from the sweet sorghum crop. The pre-treatment of bagasse for increasing biomass fermentability was optimised. After hydrolysis with commercial enzymes, 37 g glucose and 26 g xylose from 100 g bagasse could be obtained which corresponded to conversion efficiencies of 60% for cellulose and 100% for xylan. Defined media with glucose, xylose or a mixture corresponding to the sugars in the sweet sorghum bagasse hydrolysate supported growth and hydrogen production by Caldicellulosiruptor saccharolyticus. The theoretical production in the complete bioprocess under consideration from the 14.5 t sugars/ha could amount to 1.3 ton hydrogen/ha and to 2.1 ton when the bagasse is also converted to hydrogen.

Obtaining high-quality crystals for X-ray diffraction from membrane proteins has proven to be a difficult task. One recently presented method utilises the cubic phases formed by 1-monooleoyl-rac-glycerol (MO). Removing the proteins from their native environment requires the use of surfactants. One commonly used surfactant is n-octyl-beta-D-glucopyranoside (OG). Using NMR techniques and visual observations, the ternary phase diagram of MO/OG/(H2O)-H-2 was outlined at 25 degreesC. The preliminary data show that all phases present in the binary systems at this temperature are also found in the ternary. Further, at the OG-rich side, an additional phase that appears to be hexagonal occurs. Addition of minor amounts (approximate to1.5 wt/wt %) of OG converts the cubic phases of MO to a lamellar structure, while the OG-rich cubic phase is able to dissolve about 15 wt/wt % MO. OG in water forms a large micellar solution phase;. Increasing the MO concentration at constant water content leads to a series of two- and three-phase areas in which one or two phases are in equilibrium with almost pure water.

The present invention pertains to the use of at least one Brönsted superacid or metal salt of said Brönsted superacid with a DeltaGacid value of 316 kcal/mol or less, as a heat and/or colour stabiliser for polyvinyl halide resin compositions. The superacid is not a perchlorate or a trifluoromethane sulphonate. The metal in the metal salt of the Brönsted superacid is preferably selected from the group consisting of alkali metals, alkali earth metals, transition metals, lanthanide metals, actinide metals, Al, Ga, In, TI, Ge, Sn, Pb, and Sb.

The objectives of the tasks of Agrotechnology & Food Innovation (formerly ATO) in the project are: to determine at laboratory level the best conditions for producing high-yield pulps from whole jute for utilisation in wood containing papers; to test the potential of using recommended enzyme recipes in both extruder and refiner processes in terms of pulp quality, chemicals and energy consumption, brightness and production cost; to evaluate the potential of a micro-biological pre-treatment with selected strains of fungi; to establish process conditions for pilot confirmatory trials.