| 1. |
- Munthe, Christian, 1962
(författare)
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Precaution and Ethics: Handling risks, uncertainties and knowledge gaps in the regulation of new biotechnologies
- 2017
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- This volume outlines and analyses ethical issues actualized by applying a precautionary approach to the regulation of new biotechnologies. It presents a novel way of categorizing and comparing biotechnologies from a precautionary standpoint. Based on this, it addresses underlying philosophical problems regarding the ethical assessment of decision-making under uncertainty and ignorance, and discusses how risks and possible benefits of such technologies should be balanced from an ethical standpoint. It argues on conceptual and ethical grounds for a technology neutral regulation as well as for a regulation that not only checks new technologies but also requires old, inferior ones to be phased out. It demonstrates how difficult ethical issues regarding the extent and ambition of precautionary policies need to be handled by such a regulation, and presents an overarching framework for doing so.
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| 2. |
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| 3. |
- Sanli, Kemal, et al.
(författare)
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Metagenomic Sequencing of Marine Periphyton: Taxonomic and Functional Insights into Biofilm Communities
- 2015
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Ingår i: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; 6:1192
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Tidskriftsartikel (refereegranskat)abstract
- Periphyton communities are complex phototrophic, multispecies biofilms that develop on surfaces in aquatic environments. These communities harbor a large diversity of organisms comprising viruses, bacteria, algae, fungi, protozoans and metazoans. However, thus far the total biodiversity of periphyton has not been described. In this study, we use metagenomics to characterize periphyton communities from the marine environment of the Swedish west coast. Although we found approximately ten times more eukaryotic rRNA marker gene sequences compared to prokaryotic, the whole metagenome-based similarity searches showed that bacteria constitute the most abundant phyla in these biofilms. We show that marine periphyton encompass a range of heterotrophic and phototrophic organisms. Heterotrophic bacteria, including the majority of proteobacterial clades and Bacteroidetes, and eukaryotic macro-invertebrates were found to dominate periphyton. The phototrophic groups comprise Cyanobacteria and the alpha-proteobacterial genus Roseobacter, followed by different micro- and macro-algae. We also assess the metabolic pathways that predispose these communities to an attached lifestyle. Functional indicators of the biofilm form of life in periphyton involve genes coding for enzymes that catalyze the production and degradation of extracellular polymeric substances, mainly in the form of complex sugars such as starch and glycogen-like meshes together with chitin. Genes for 278 different transporter proteins were detected in the metagenome, constituting the most abundant protein complexes. Finally, genes encoding enzymes that participate in anaerobic pathways, such as denitrification and methanogenesis, were detected suggesting the presence of anaerobic or low-oxygen micro-zones within the biofilms.
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| 4. |
- Sandin, Per, et al.
(författare)
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Technology neutrality and regulation of agricultural biotechnology
- 2018
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Ingår i: Professionals in food chains: ethics, rules and responsibility. EurSafe 2018, Vienna, Austria 13 – 16 June 2018 / edited by: Svenja Springer, Herwig Grimm. - Wageningen, Netherlands : Wageningen Academic Publishers. - 9789086863211
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Konferensbidrag (refereegranskat)abstract
- Agricultural biotechnology, in particular genetically modified organisms (GMOs), is subject to regulation in many areas of the world, not least in the European Union (EU). A number of authors have argued that those regulatory processes are unfair, costly, and slow and that regulation therefore should move in the direction of increased ‘technology neutrality’. The issue is becoming more pressing, especially since new biotechnologies such as CRISPR increasingly blur the regulatory distinction between GMOs and non-GMOs. This paper offers a definition of technology neutrality, uses the EU GMO regulation as a starting point for exploring technology neutrality, and presents distinctions between variants of the call for technology neutral GMO regulation in the EU.
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| 5. |
- Sandhi, Arifin, 1986-, et al.
(författare)
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Phytofiltration of arsenic by aquatic moss (Warnstorfia fluitans)
- 2017
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424.
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Tidskriftsartikel (refereegranskat)abstract
- This work investigates whether aquatic moss (Warnstorfia fluitans) originating from an arsenic (As)-contaminated wetland close to a mine tailings impoundment may be used for phytofiltration of As. The aim was to elucidate the capacity of W. fluitans to remove As from arsenite and arsenate contaminated water, how nutrients affect the As uptake and the proportion of As adsorption and absorption by the moss plant, which consists of dead and living parts.Arsenic removal from 0, 1, or 10% Hoagland nutrient solution containing 0–100 μM arsenate was followed over 192 h, and the total As in aquatic moss after treatment was analysed. The uptake and speciation of As in moss cultivated in water containing 10 μM arsenate or arsenite were examined as As uptake in living (absorption + adsorption) and dead (adsorption) plant parts.Results indicated that W. fluitans removed up to 82% of As from the water within one hour when 1 μM arsenate was added in the absence of nutrients. The removal time increased with greater nutrient and As concentrations. Up to 100 μM As had no toxic effect on the plant biomass. Both arsenite and arsenate were removed from the solution to similar extents and, independent of the As species added, more arsenate than arsenite was found in the plant. Of the As taken up, over 90% was firmly bound to the tissue, a possible mechanism for resisting high As concentrations. Arsenic was both absorbed and adsorbed by the moss, and twice as much As was found in living parts as in dead moss tissue. This study revealed that W. fluitans has potential to serve as a phytofilter for removing As from As-contaminated water without displaying any toxic effects of the metalloid.
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| 6. |
- Zubair, Muhammad
(författare)
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Genetic variation, biochemical contents and wound healing activity of Plantago major
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Plantago major L. (greater plantain, common plantain) has been used as a wound healing remedy in different parts of the world for centuries. Different bioactive compounds have been proposed to contribute to the wound healing properties of this plant. The present study was undertaken to investigate the impact of some genetic and environmental factors on the wound healing activity of common plantain. Seeds of P. major were collected from five populations in different parts of Sweden, and were germinated and grown in a greenhouse. As expected for an inbreeding species, RAPD analyses demonstrated considerable between-population variation but very sparse within-population and within-subpopulation variation. Six major phenolic compounds were encountered in samples of P. major, four of which were identified for the first time in this thesis; PLMA 1–PLMA 4. Between-population and sub-population differences in the contents of these chemical compounds showed no correlation with RAPD-based estimates of genetic relatedness. The contents of these compounds differed greatly between different plant organs of P. major. The highest concentration of plantamajoside and PLMA 2 was found in leaves whereas the highest concentration of verbascoside was found in flower stalks and seeds. Contents were significantly higher in freeze-dried leaf samples compared to samples dried at higher temperatures. Both water and ethanol-based extracts of P. major leaves stimulated the cell proliferation and migration in an in vitro scratch assay, and also showed anti-inflammatory activity in an in vitro NF-kB assay with oral epithelial cell cultures. Similarly, these extracts stimulated wound healing activities in ex vivo tests using detached pig ears. Further breeding efforts aimed at developing P. major as a crop plant, and medicinal research aimed at elucidating and optimizing extracts with wound healing properties, are thus warranted.
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| 7. |
- Wang, Yang
(författare)
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Discovery and investigation of glycoside hydrolase family 5 enzymes with potential use in biomass conversion
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Glycoside hydrolases (GHs) cleave glycosidic bonds in glycoconjugates, oligosaccharides and polysaccharides such as cellulose and various hemicelluloses. Mannan is a major group of hemicelluloses. In higher plants, they usually serve as storage carbohydrates in seeds and tubers or as structural polysaccharides cross-linking with cellulose/lignin in cell walls. In industrial fields, this renewable biomass component can be used in various areas such as production of biofuels and health-benefit manno-oligosaccharides; and mannan degrading enzymes, especially mannanases, are important molecular tools for controlling mannan polysaccharides properties in biomass conversion. In this thesis, the evolution, substrate specificity and subfamily classification of the most important GH family, i.e., glycoside hydrolase family 5 (GH5), are presented providing a powerful tool for exploring GH5 enzymes in search for enzymes with interesting properties for sustainable biomass conversion. Additionally, three GH5_7 mannanases from Arabidopsis thaliana (AtMan5-1, AtMan5-2 and AtMan5-6) were investigated in the present study. Bioinformatics tools, heterologous expression, and enzymology were applied in order to reveal the catalytic properties of the target enzymes, increase understanding of plant mannanase evolution, and evaluate their potential use in biomass conversion. This approach revealed: (1) AtMan5-1 exhibits mannan hydrolase/transglycosylase activity (MHT), (2) AtMan5-2 preferably degrades mannans with a glucomannan backbone, and (3) AtMan5-6 is a relatively thermotolerant enzyme showing high catalytic efficiency for conversion of glucomannan and galactomannan making this plant mannanase an interesting candidate for biotechnological applications of digesting various mannans. Moreover, these studies suggest an evolutionary diversification of plant mannanase enzymatic function.
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| 8. |
- Björk, Mats, 1960-, et al.
(författare)
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Methane emissions from macrophyte beach wrack on Baltic seashores
- 2023
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Ingår i: Ambio. - : Springer Nature. - 0044-7447 .- 1654-7209. ; 52:1, s. 171-181
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Tidskriftsartikel (refereegranskat)abstract
- Beach wrack of marine macrophytes is a natural component of many beaches. To test if such wrack emits the potent greenhouse gas methane, field measurements were made at different seasons on beach wrack depositions of different ages, exposure, and distance from the water. Methane emissions varied greatly, from 0 to 176 mg CH4-C m−2 day−1, with a clear positive correlation between emission and temperature. Dry wrack had lower emissions than wet. Using temperature data from 2016 to 2020, seasonal changes in fluxes were calculated for a natural wrack accumulation area. Such calculated average emissions were close to zero during winter, but peaked in summer, with very high emissions when daily temperatures exceeded 20 °C. We conclude that waterlogged beach wrack significantly contributes to greenhouse gas emissions and that emissions might drastically increase with increasing global temperatures. When beach wrack is collected into heaps away from the water, the emissions are however close to zero.
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| 9. |
- Almered Olsson, Gunilla, 1951, et al.
(författare)
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Food systems sustainability - For whom and by whom? : An examination of different 'food system change' viewpoints
- 2018
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Ingår i: Development Research Conference 2018: “Rethinking development”, 22–23 August 2018, Gothenburg, Sweden.
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Konferensbidrag (refereegranskat)abstract
- The United Nations identifies the food crisis as one of the primary overarching challenges facing the international community. Different stakeholders in the food system have widely different perspectives and interests, and challenging structural issues, such as the power differentials among them, remain largely unexamined. These challenges make rational discourse among food system actors from different disciplines, sectors and levels difficult. These challenges can often prevent them from working together effectively to find innovative ways to respond to food security challenges. This means that finding solutions to intractable and stuck issues, such as the food crisis often stall, not at implementation, but at the point of problem identification. Food system sustainability means very different things to different food system actors. These differences in no way undermine or discount the work carried out by these players. However, making these differences explicit is an essential activity that would serve to deepen theoretical and normative project outcomes. Would the impact and reach of different food projects differ if these differences were made explicit? The purpose of this initial part of a wider food system research project is not to search for difference or divergence, with the aim of critique, but rather to argue that by making these differences explicit, the overall food system project engagement will be made more robust, more inclusive and more encompassing. This paper starts with some discussion on the different food system perspectives, across scales, regions and sectors but focuses primarily on the design of processes used to understand these divergent and at times contradictory views of what a sustainable food system may be. This paper draws on ongoing work within the Mistra Urban Futures project, using the food system projects in cities as diverse as Cape Town, Manchester, Gothenburg and Kisumu as sites for this enquiry.
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| 10. |
- Roos, Jonas
(författare)
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Verticillium longisporum and plant immunity responses in Arabidopsis
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Verticillium spp. are soil-borne ascomycete fungi belonging to a subgroup of Sordariomycetes, and the three major plant pathogens Verticillium longisporum, V. dahliae and V. albo-atrum cause disease on numerous plant species worldwide. In Sweden, V. longisporum poses a threat to Brassica oilseed crops, and is thus emphasized in this thesis. Here the early immune responses to V. longisporum in the model plant Arabidopsis and recent data on the V. longisporum genome are presented. Three genes of importance in the Arabidopsis–V. longisporum interaction were studied. The genes were identified via transcriptome and single nucleotide polymorphism (SNP) analysis. RabGAP22, a RabGTPase-regulating protein, was found to contribute to V. longisporum resistance. Pull-down assays revealed SERINE:GLYOXYLATE AMINOTRANSFERASE (AGT1) as an interacting partner during V. longisporum infection and the two proteins were shown to co-localize in the peroxisomes. Unexpectedly, a role for RabGAP22 was also found in stomatal immunity. The monoterpene synthase TPS23/27 was on the other hand found to contribute to fungal invasion, by triggering germination of V. longisporum conidia. The third gene codes for a nitrate/peptide transporter, NPF5.12. Pull-down experiments and fluorescent imaging revealed interaction between NPF5.12 and a major latex protein family member, NPFBP1. Implications in plant immunity processes of these three genes are further discussed. The genomes of two Swedish V. longisporum isolates were sequenced and found to have a size of approximately 70 Mb and harbor ~21,000 protein-coding genes. Initial analyses revealed that 86% of the V. longisporum genomes are shared with V. dahliae and V. albo-atrum, with a high extent of gene duplications. Large numbers of proteins were predicted to contain secretion motifs, and this group of proteins is presumed to play major roles in the interactions with V. longisporum host plants. In conclusion, this thesis work has revealed new fungal and plant host genes and thereby laid the basis for new plant breeding and disease protection strategies.
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| 11. |
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| 12. |
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| 13. |
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| 14. |
- Ahlman, Linnéa, 1987, et al.
(författare)
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Stress Detection Using Proximal Sensing of Chlorophyll Fluorescence on the Canopy Level
- 2021
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Ingår i: AgriEngineering. - : MDPI AG. - 2624-7402. ; 3:3, s. 648-668
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Tidskriftsartikel (refereegranskat)abstract
- Chlorophyll fluorescence is interesting for phenotyping applications as it is rich in biological information and can be measured remotely and non-destructively. There are several techniques for measuring and analysing this signal. However, the standard methods use rather extreme conditions, e.g., saturating light and dark adaption, which are difficult to accommodate in the field or in a greenhouse and, hence, limit their use for high-throughput phenotyping. In this article, we use a different approach, extracting plant health information from the dynamics of the chlorophyll fluorescence induced by a weak light excitation and no dark adaption, to classify plants as healthy or unhealthy. To evaluate the method, we scanned over a number of species (lettuce, lemon balm, tomato, basil, and strawberries) exposed to either abiotic stress (drought and salt) or biotic stress factors (root infection using Pythium ultimum and leaf infection using Powdery mildew Podosphaera aphanis ). Our conclusions are that, for abiotic stress, the proposed method was very successful, while, for powdery mildew, a method with spatial resolution would be desirable due to the nature of the infection, i.e., point-wise spread. Pythium infection on the roots is not visually detectable in the same way as powdery mildew; however, it affects the whole plant, making the method an interesting option for Pythium detection. However, further research is necessary to determine the limit of infection needed to detect the stress with the proposed method.
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| 15. |
- Berglund, Jennie
(författare)
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Wood Hemicelluloses - Fundamental Insights on Biological and Technical Properties
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hemicelluloses are a group of heterogeneous polysaccharides representing around 30 % of wood where the dominating types are xylans, glucomannans and xyloglucans. Hemicelluloses complex molecular structure makes it difficult to understand the relationship between structure and properties entirely, and their biological role is not yet fully verified. Additionally, hemicelluloses are sensitive to chemical processing and are not utilized to their full potentials for production of value-added products such as materials, additives to food and pharmaceutical products, etc. Increased knowledge regarding their functions is important for the development of both processes and products. The aim with this work has therefore been to increase the fundamental understanding about how the structure and properties of wood hemicelluloses are correlated, and properties such as flexibility, interaction with cellulose, solubility, resistance to chemical-, thermal-, and enzymatic degradation have been explored.Molecular dynamics (MD) simulations were used to, in detail, study the structures found in wood hemicelluloses. The flexibility was evaluated by comparing the impact of backbone sugars on the conformational space and also the impact of side groups was considered. Based on the conformational space of backbone glycosidic linkages the flexibility order of hemicelluloses in an aqueous environment was determined to be: xylan > glucomannan > xyloglucan. Additionally, the impact of xylan structure on cellulose interaction was evaluated by MD methods.Hemicelluloses were extracted from birch and spruce, and were used to fabricate different composite hydrogels with bacterial cellulose. These materials were studied with regards to mechanical properties, and it was shown that galactoglucomannans mainly contributed to an increased modulus in compression, whereas the most significant effect from xylan was increased strain under uniaxial tensile testing. Besides, other polysaccharides of similar structure as galactoglucomannans were modified and used as pure, well defined, models. Acetyl groups are naturally occurring decorations of wood hemicelluloses and can also be chemically introduced. Here, mannans with different degrees of acetylation were prepared and the influence of structure on solubility in water and the organic solvent DMSO were evaluated. Furthermore, the structure and water solubility influenced the interaction with cellulose. Acetylation also showed to increase the thermal and biological stability of mannans.With chemical pulping processes in mind, the degradability of spruce galactoglucomannans in alkaline solution were studied with regards to the structure, and the content of more or less stable structural regions were proposed.
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| 16. |
- Guschanski, Katerina, et al.
(författare)
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The evolution of duplicate gene expression in mammalian organs
- 2017
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Ingår i: Genome Research. - : Cold Spring Harbor Laboratory. - 1088-9051 .- 1549-5469. ; 27:9, s. 1461-1474
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Tidskriftsartikel (refereegranskat)abstract
- Gene duplications generate genomic raw material that allows the emergence of novel functions, likely facilitating adaptive evolutionary innovations. However, global assessments of the functional and evolutionary relevance of duplicate genes in mammals were until recently limited by the lack of appropriate comparative data. Here, we report a large-scale study of the expression evolution of DNA-based functional gene duplicates in three major mammalian lineages (placental mammals, marsupials, egg-laying monotremes) and birds, on the basis of RNA sequencing (RNA-seq) data from nine species and eight organs. We observe dynamic changes in tissue expression preference of paralogs with different duplication ages, suggesting differential contribution of paralogs to specific organ functions during vertebrate evolution. Specifically, we show that paralogs that emerged in the common ancestor of bony vertebrates are enriched for genes with brain-specific expression and provide evidence for differential forces underlying the preferential emergence of young testis-and liver-specific expressed genes. Further analyses uncovered that the overall spatial expression profiles of gene families tend to be conserved, with several exceptions of pronounced tissue specificity shifts among lineage-specific gene family expansions. Finally, we trace new lineage-specific genes that may have contributed to the specific biology of mammalian organs, including the little-studied placenta. Overall, our study provides novel and taxonomically broad evidence for the differential contribution of duplicate genes to tissue-specific transcriptomes and for their importance for the phenotypic evolution of vertebrates.
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| 17. |
- Stedt, Kristoffer, 1991, et al.
(författare)
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Post-harvest cultivation with seafood process waters improves protein levels of Ulva fenestrata while retaining important food sensory attributes
- 2022
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Ingår i: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745.
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Tidskriftsartikel (refereegranskat)abstract
- Seaweed aquaculture can provide the growing human population with a sustainable source of proteins. Sea-based cultivation is an effective method for farming seaweeds on a large scale and can yield high biomass output. However, the quality and biochemical composition of the biomass is seasonally dependent, which limits the harvests to certain periods of the year. Here we show the possibility to extend the sea-based cultivation season of Ulva fenestrata when aiming for high protein levels, by post-harvest treatment in herring production process waters. We harvested U. fenestrata at an optimal period in terms of yield, but suboptimal in terms of protein content. We then cultivated the seaweed in onshore tank systems with the nutrient-rich process waters for 14 days. We monitored biomass yield, crude protein content, amino acid composition, and content of the health concerning metals arsenic, mercury, lead, and cadmium, as well as the sensory properties of the dried biomass. After cultivation in the process waters, biomass yields were 30 - 40% higher (210 – 230 g fresh weight) compared to in seawater (160 g fresh weight). Also, the crude protein and amino acid content increased three to five times in the process waters, reaching 12 - 17 and 15 – 21% dry weight, respectively. The protein enriched biomass followed food graded standards for heavy metal content, and consumption of the biomass does not exceed health based reference points. Additionally, no sensory attributes regarded as negative were found. This rapid, post-harvest treatment can help extend the cultivation season of sea-based seaweed farms, maximizing their output of sustainable proteins.
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| 18. |
- Steinhagen, Sophie, et al.
(författare)
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Harvest time can affect the optimal yield and quality of sea lettuce (Ulva fenestrata) in a sustainable sea-based cultivation : Seasonal Cultivation of Ulva fenestrata
- 2022
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Ingår i: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Seaweed biomass is a renewable resource with multiple applications. Sea-based cultivation of seaweeds can provide high biomass yields, low construction, operation, and maintenance costs and could offer an environmentally and economically sustainable alternative to land-based cultivations. The biochemical profile of sea-grown biomass depends on seasonal variation in environmental factors, and the optimization of harvest time is important for the quality of the produced biomass. To identify optimal harvest times of Swedish sea-based cultivated sea lettuce (Ulva fenestrata), this study monitored biomass yield, morphology, chemical composition, fertility, and biofouling at five different harvesting times in April - June 2020. The highest biomass yields (approx. 1.2 kg fw [m rope]-1) were observed in late spring (May). The number and size of holes in the thalli and the amount of fertile and fouled tissue increased with prolonged growth season, which together led to a significant decline in both biomass yield and quality during summer (June). Early spring (April) conditions were optimal for obtaining high fatty acid, protein, biochar, phenolic, and pigment contents in the biomass, whereas carbohydrate and ash content, as well as essential and non-essential elements, increased later in the growth season. Our study results show that the optimal harvest time of sea-based cultivated U. fenestrata depends on the downstream application of the biomass and must be carefully selected to balance yield, quality, and desired biochemical contents to maximize the output of future sea-based algal cultivations in the European Northern Hemisphere.
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| 19. |
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| 20. |
- Schrader, J., et al.
(författare)
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Cambial meristem dormancy in trees involves extensive remodelling of the transcriptome
- 2004
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Ingår i: The Plant Journal. - Malden : Wiley-Blackwell. - 0960-7412 .- 1365-313X. ; 40:2, s. 173-187
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Tidskriftsartikel (refereegranskat)abstract
- The establishment of the dormant state in meristems involves considerable physiological and metabolic alterations necessary for surviving unfavourable growth conditions. However, a global molecular analysis of dormancy in meristems has been hampered by the difficulty in isolating meristem cells. We used cryosectioning to isolate purified cambial meristem cells from the woody plant Populus tremula during active growth and dormancy. These samples were used to generate meristem-specific cDNA libraries and for cDNA microarray experiments to define the global transcriptional changes underlying cambial dormancy. The results indicate a significant reduction in the complexity of the cambial transcriptome in the dormant state. Although cell division is terminated in the dormant cambium, the cell cycle machinery appears to be maintained in a skeletal state as suggested by the continued presence of transcripts for several cell cycle regulators. The downregulation of PttPIN1 and PttPIN2 transcripts explains the reduced basipetal polar auxin transport during dormancy. The induction of a member of the SINA family of ubiquitin ligases implicated in auxin signalling indicates a potential mechanism for modulation of auxin sensitivity during cambial dormancy. The metabolic alterations during dormancy are mirrored in the induction of genes involved in starch breakdown and the glyoxysomal cycle. Interestingly, the induction of RGA1 like gene suggests modification of gibberellin signalling in cambial dormancy. The induction of genes such as poplar orthologues of FIE and HAP2 indicates a potential role for these global regulators of transcription in orchestrating extensive changes in gene expression during dormancy.
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| 21. |
- Sweetlove, Lee J., et al.
(författare)
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Engineering central metabolism – a grand challenge for plant biologists
- 2017
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Ingår i: Plant Journal. - : Wiley. - 0960-7412 .- 1365-313X. ; 90:4, s. 749-763
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Tidskriftsartikel (refereegranskat)abstract
- The goal of increasing crop productivity and nutrient-use efficiency is being addressed by a number of ambitious research projects seeking to re-engineer photosynthetic biochemistry. Many of these projects will require the engineering of substantial changes in fluxes of central metabolism. However, as has been amply demonstrated in simpler systems such as microbes, central metabolism is extremely difficult to rationally engineer. This is because of multiple layers of regulation that operate to maintain metabolic steady state and because of the highly connected nature of central metabolism. In this review we discuss new approaches for metabolic engineering that have the potential to address these problems and dramatically improve the success with which we can rationally engineer central metabolism in plants. In particular, we advocate the adoption of an iterative ‘design-build-test-learn’ cycle using fast-to-transform model plants as test beds. This approach can be realised by coupling new molecular tools to incorporate multiple transgenes in nuclear and plastid genomes with computational modelling to design the engineering strategy and to understand the metabolic phenotype of the engineered organism. We also envisage that mutagenesis could be used to fine-tune the balance between the endogenous metabolic network and the introduced enzymes. Finally, we emphasise the importance of considering the plant as a whole system and not isolated organs: the greatest increase in crop productivity will be achieved if both source and sink metabolism are engineered.
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| 22. |
- Vågsholm, Ivar
(författare)
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Statement on a request from the European Commission for the assessment of the scientific elements supporting the prohibition for the placing on the market of GM potato EH92-527-1 for cultivation purposes in Austria
- 2012
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Ingår i: EFSA Journal. - : Wiley. - 1831-4732. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Austria notified to the European Commission its ordinance implementing a national safeguard measure prohibiting the placing on the market of GM potato EH92-527-1 for cultivation purposes in Austria, after which the European Commission asked the European Food Safety Authority to assess the scientific elements supporting the prohibition. Having considered the information package provided by Austria and all relevant scientific publications, the GMO and BIOHAZ Panels concluded that: i) no new data specific to the safety of the nptII gene have been provided; ii) the risk posed by the formation of mosaic structures of aminoglycoside phosphotransferase genes could not be assessed without data documenting the existence of such structures among the existing gene variants and such data were not provided; iii) the therapeutic relevance of kanamycin and neomycin was already addressed in the EFSA's opinion on ARM genes and as of yet there is no evidence to indicate that resistance to these antibiotics in clinically-relevant bacteria has developed as a result of acquisition of the nptII gene; iv) the knowledge gaps and uncertainties highlighted in the Austrian document have already been considered in the EFSA's opinion on ARM genes. Austria did not provide any new or additional information on the molecular characterisation or PMEM of potato EH92-527-1 after the date of consent for this GM event that would require the reassessment of existing information. The EFSA GMO Panel reiterates its scientific opinion on the 2010 monitoring report of GM potato EH92-527-1 in which it provides specific recommendations to improve the methodology of the PMEM of the GM potato. Further, the EFSA GMO Panel concludes that no grounds exist to date that would lead to reconsideration of its opinion on GM potato EH92-527-1.
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| 23. |
- Ivarson, Emelie, et al.
(författare)
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Effects of overexpression of WRI1 and hemoglobin genes on the seed oil content of Lepidium campestre
- 2017
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Ingår i: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- The wild species field cress (Lepidium campestre), belonging to the Brassicaceae family, has potential to be developed into a novel oilseed- and catch crop, however, the species needs to be further improved regarding some important agronomic traits. One of them is its low oil content which needs to be increased. As far as we know there is no study aiming at increasing the oil content that has been reported in this species. In order to investigate the possibility to increase the seed oil content in field cress, we have tried to introduce the Arabidopsis WRINKLED1 (AtWRI1) or hemoglobin (Hb) genes from either Arabidopsis thaliana (AtHb2) or Beta vulgaris (BvHb2) into field cress with the seed specific expression. The hypothesis was that the oil content would be increased by overexpressing these target genes. The results showed that the oil content was indeed increased by up to 29.9, 20.2, and 25.9% in the transgenic lines expressing AtWRI1, AtHb2, and BvHb2, respectively. The seed oil composition of the transgenic lines did not significantly deviate from the seed oil composition of the wild type plants. Our results indicate that genetic modification can be used in this wild species for its fast domestication into a future economically viable oilseed and catch crop.
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| 24. |
- Kianersi, Farzad, et al.
(författare)
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Biosynthesis of rutin changes in Capparis spinosa due to altered expression of its pathway genes under elicitors' supplementation
- 2020
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Ingår i: Plant Cell Tissue and Organ Culture. - : Springer Nature. - 0167-6857 .- 1573-5044. ; 141:3, s. 619-631
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Tidskriftsartikel (refereegranskat)abstract
- Caper plant is (Capparis spinosa L.) a good source of rutin which plays a key role in the human diet. In this study, the effect of different concentrations of salicylic acid (SA) and methyl jasmonate (MeJA) on the weight of anther-derived calli and their rutin contents were assessed in caper plants. Also, we investigated the rutin content and expression pattern of some rutin related genes in leaves of caper plants at vegetative and fresh fruiting growth stages under SA and MeJA treatments. In the first experiment, the highest rutin contents were observed in anther-derived calli treated with 10 mu M MeJA and 100 mg L-1 SA after 2 weeks from initial treatments, which were 2.44 and 2.22-fold higher than control. Also, the treatment of caper plants with150 mu M MeJA and 100 mg L-1 SA resulted in a higher increase in the rutin content of leaves at the fresh fruiting stage (61.46 and 9.99 mg g(-1) DW, respectively), in the second experiment. Among the studied genes, the FLS gene showed the highest expression in the leaves of the MeJA- and SA-treated plants at vegetative growth stage, while in the fresh fruiting stage the highest expression was related to the RT gene. Use of 150 mu M MeJA and 100 mg L-1 SA enhanced the expression levels of the RT gene up to 7.36 and 2.89 times of the control, respectively. These results suggest that rutin content and the expression patterns of rutin biosynthesis genes in caper can be significantly enhanced by the SA and MeJA treatments in a growth stage-dependent manner. Key message Methyl jasmonate and salicylic acid treatments enhance the rutin contents of Capparis spinosa in vitro and in vivo and up-regulate the rutin biosynthetic related genes at two different growth stages.
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- Niazi, Adnan, et al.
(författare)
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Genome Analysis of Bacillus amyloliquefaciens Subsp. plantarum UCMB5113: A Rhizobacterium That Improves Plant Growth and Stress Management
- 2014
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- The Bacillus amyloliquefaciens subsp. plantarum strain UCMB5113 is a Gram-positive rhizobacterium that can colonize plant roots and stimulate plant growth and defense based on unknown mechanisms. This reinforcement of plants may provide protection to various forms of biotic and abiotic stress. To determine the genetic traits involved in the mechanism of plantbacteria association, the genome sequence of UCMB5113 was obtained by assembling paired-end Illumina reads. The assembled chromosome of 3,889,532 bp was predicted to encode 3,656 proteins. Genes that potentially contribute to plant growth promotion such as indole-3-acetic acid (IAA) biosynthesis, acetoin synthesis and siderophore production were identified. Moreover, annotation identified putative genes responsible for non-ribosomal synthesis of secondary metabolites and genes supporting environment fitness of UCMB5113 including drug and metal resistance. A large number of genes encoding a diverse set of secretory proteins, enzymes of primary and secondary metabolism and carbohydrate active enzymes were found which reflect a high capacity to degrade various rhizosphere macromolecules. Additionally, many predicted membrane transporters provides the bacterium with efficient uptake capabilities of several nutrients. Although, UCMB5113 has the possibility to produce antibiotics and biosurfactants, the protective effect of plants to pathogens seems to be indirect and due to priming of plant induced systemic resistance. The availability of the genome enables identification of genes and their function underpinning beneficial interactions of UCMB5113 with plants.
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