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  • 1.
    Abghoui, Younes
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Computational design, synthesis, and characterization of oseltamivir molecularly imprinted polymers2012Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
  • 2.
    Abrahamsson, Victor
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Development of a fluorometric method for the quantification of sulfite and thiol-containing compounds in beer2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sulfite is the most important antioxidant in beer. Quantification of sulfite is crucial due to restrictions as an additive and for investigative purposes of sulfite and thiol-containing proteins role as redox mediators. A method based on fluorometric determination of sulfite and thiol-containing compounds in beer was developed. The analytes were derivatized with ThioGlo®  1 and subsequently separated on a C18 column with wide pore size, featuring a high-performance liquid chromatography system equipped with fluorescence detector. Two peaks corresponding to sulfite derivatives were observed. The two derivatives were assessed with exact mass spectrometry and both provided identical mass spectra. To compensate for adverse matrix effects in samples a matrix-matched calibration curve is proposed. Sulfite diminished in an inverse exponential manner upon hydrogen peroxide addition in beer. The amount of thiol groups decreased when beer was subjected to oxidative stress, thus confirming its antioxidative role in beer.

  • 3.
    Abrahamsson, Victor
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Hoff, Signe
    University of Copenhagen, Denmark.
    Nielsen, Nikoline J.
    University of Copenhagen, Denmark.
    Lund, Marianne N.
    University of Copenhagen, Denmark.
    Andersen, Mogens L.
    University of Copenhagen, Denmark.
    Determination of Sulfite in Beer Based on Fluorescent Derivatives and Liquid Chromatographic Separation2012In: Journal of the American Society of Brewing Chemists, ISSN 0361-0470, E-ISSN 1943-7854, Vol. 70, no 4, p. 296-302Article in journal (Refereed)
    Abstract [en]

    A method was developed for quantification of sulfite in beer based on derivatization with the maleimide-derived probe ThioGlo I followed by separation of fluorescent adducts by reversed-phase high-performance liquid chromatography and fluorescence detection. Sulfite gave two ThioGlo 1 derivatives and it was shown by mass spectrometry that both had identical mass spectra. Matrix effects were observed when constructing sulfite standard curves in different beers and, therefore, use of a matrix-matched calibration curve is proposed. ThioGlo I was found to generate fluorescent adducts with both bound and free sulfite, providing a quantification of the total sulfite content in beer. The limit of quantification of sulfite was 0.6 mg/L and the method can be used for quantification of sulfite in highly colored beers.

  • 4.
    Adbo, Karina
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Andersson, Håkan S.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ankarloo, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Karlsson, Jesper G.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Norell, M C
    Olofsson, Linus
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Svenson, Johan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Örtegren, U
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Enantioselective synthetic receptors for Tröger’s base1999In: Bioorganic Chemistry, Vol. 27, no 5, p. 363-371Article in journal (Refereed)
  • 5.
    Adbo, Karina
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Vidal Carulla, Clara
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Designing play-based learning chemistry activities in the preschool environment2019In: Chemistry Education Research and Practice, ISSN 1756-1108, E-ISSN 1756-1108Article in journal (Refereed)
    Abstract [en]

    This study focuses on the design of play-based learning activities for chemistry in preschool. Viewing chemistry as a part of our past and present culture instead of as a subject, provides the backdrop for a more holistic approach to chemistry within this specific environment. A cultural-historical perspective, together with scaffolding, emergent science skills and sustained shared thinking, made up the framework for the design of the learning activities. Results show that when scaffolding and emergent science skills are used within the design, they provide good support for both the content and the teacher in the actual learning situation. Working with scaffolding was also beneficial for professional development. However, for a progressive and inclusive activity design, it is essential to take into account aspects of the immediate environment and methods for direct evaluation.

  • 6.
    Agell, Blenda
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Effect of Antibacterial Mouthwash on Basal Metabolic Rate in Humans: A Randomized, Double-blinded, Cross-over Study2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of mouthwash is a common complement to oral care. However, the physiological implication of this use, besides of effects on oral hygiene, is poorly known. The research of the gut micro flora and its implications on the host is a very active area of research today. Many important connections between the gut micro flora and obesity and diabetes have been found. These billions of bacteria are part of the immune system, they produce essential vitamins and they make inaccessible polysaccharides more digestible to the host, just to mention a few of their symbiotic roles for the host.

    A less explored area is the micro flora in the oral cavity. On the back of the tongue, anaerobic bacteria can reduce dietary nitrate to nitrite which then further can be reduced to nitric oxide, NO. NO is important in several important biological functions, e.g. as a signal substance, vasoregulation, mucus production and antibacterial effects. Vegetables as beetroot and spinach are dietary sources with a high nitrate content. Also drinking water and processed meats can be of relevance. Nitrite is added to processed meat for the prevention of botulism but also adds taste and color.  

    Experiments on humans indicate that mitochondrial efficiency increases after nitrate load, manifested as a decreased oxygen demand during physical exercise. This can also be relevant under conditions where the mitochondrial function is impaired, such as in diabetes and cardiovascular diseases.

    First a pilot study was made to evaluate the nitrate reducing effect from the antibacterial mouthwash. The mouthwash proved very effective. The concentrations of nitrate and nitrite in saliva was analyzed by HPLC and saliva from the antibacterial treatment showed greatly reduced concentrations of nitrite and high concentrations of nitrate. Saliva from placebo mouthwash showed high concentrations of nitrite and low concentrations of nitrate as expected.

    To study the importance of oral bacteria on metabolism, we performed a randomized, cross-over double-blinded study with 19 healthy males between 22-43 years. During two separate three-day periods they used an antibacterial and placebo mouthwash, respectively. On the fourth day their basal metabolic rate (BMR) was measured with an indirect calorimetric system. Moreover, samples from saliva, urine and blood were collected but these results are not included in this thesis. An earlier, unpublished study has demonstrated that nitrate administration reduces the basal metabolic rate. Accordingly, our aim was to study potential effects on the basal metabolic rate following reduction of the number of oral bacteria by aid of antibacterial mouthwash. Our hypothesis was that the reduced availability of nitrite would decrease the availability of NO in the body and manifest as an increased basal metabolic rate.

    The results from indirect calorimetry measurements showed no significant difference between placebo and antibacterial mouthwash, but there may be confounding factors. Further study is needed to assess the potential effects on host metabolism by these bacteria.

  • 7.
    Ahlin, Ellen
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Utvärdering av dricksvattenkvaliteten i Bjuv: Kartläggning av klagomål och eftersökning av orsak2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vid bytet från grundvattentäkt till ytvattentäkt i Bjuvs kommun började klagomål om dricksvattnets kvalitet att strömma in till Nordvästra Skånes Vatten och Avlopp (NSVA), ansvarig för vattenverksamheten i kommunen. Syftet med denna studie är att kartlägga klagomålen kring dricksvattnet, ringa in problemet och eftersöka orsaken. Detta har skett genom intervjuer med konsumenter liksom vattenprovtagningar hos dessa. En geografisk spridning låg till grund vid valet av provtagningspunkterna. Utöver mikrobiologiska, kemiska och fysikaliska parametrar som inkluderas i Livsmedelsverkets föreskrifter om dricksvatten har vattnet analyserats för innehåll av geosmin, 2-metylisoborneol och 2,4,6-trikloranisol då dessa föreningar är kända för att orsaka dålig lukt och bismak på dricksvatten. Analysresultaten visar generellt på ett vatten med god kvalitet. Av de intervjuer som gjorts hos de utvalda konsumenterna framgår det dock att vattenkvaliteten inte är tillfredsställande. Det är i huvudsak vattnets lukt och smak som kritiseras där unken och mögel är den vanligaste beskrivningen. Vad denna lukt och smak beror på har inte kunnat fastställas. En kartläggning av klagomålen och definiering av problemet har dock påbörjats vilket underlättar för fortsatta studier och eventuella åtgärder.

  • 8.
    Ahlstrand, Emma
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Hermansson, Kersti
    Uppsala University.
    Friedman, Ran
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Interaction Energies in Complexes of Zn and Amino Acids: A Comparison of Ab Initio and Force Field Based Calculations2017In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 121, no 13, p. 2643-2654Article in journal (Refereed)
    Abstract [en]

    Zinc plays important roles in structural stabilization of proteins, eniyine catalysis, and signal transduction. Many Zn binding sites are located at the interface between the protein and the cellular fluid. In aqueous solutions, Zn ions adopt an octahedral coordination, while in proteins zinc can have different coordinations, with a tetrahedral conformation found most frequently. The dynainics of Zn binding to proteins and the formation of complexes that involve Zn are dictated by interactions between Zn and its binding partners. We calculated the interaction energies between Zn and its ligands in complexes that mimic protein binding sites and in Zn complexes of water and one or two amino acid moieties, using quantum mechanics (QM) and molecular mechanics (MM). It was found that MM calculations that neglect or only approximate polarizability did not reproduce even the relative order of the QM interaction energies in these complexes. Interaction energies calculated with the CHARMM-Diode polarizable force field agreed better with the ab initio results,:although the deviations between QM and MM were still rather large (40-96 kcallmol). In order to gain further insight into Zn ligand interactions, the free energies of interaction were estimated by QM calculations with continuum solvent representation, and we performed energy decomposition analysis calculations to examine the characteristics of the different complexes. The ligand-types were found to have high impact on the relative strength of polarization and electrostatic interactions. Interestingly, ligand ligand interactions did not play a significant role in the binding of Zn. Finally) analysis of ligand exchange energies suggests that carboxylates could be exchanged with water molecules, which explains the flexibility in Zn:binding dynamics. An exchange between earboxylate (Asp/Glii) and imidazole (His) is less likely.

  • 9.
    Ahlstrand, Emma
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Spångberg, Daniel
    Uppsala University.
    Hermansson, Kersti
    Uppsala University.
    Friedman, Ran
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Interaction energies between metal ions (Zn2+ and Cd2+) and biologically relevant ligands2013In: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 113, no 23, p. 2554-2562Article in journal (Refereed)
    Abstract [en]

    Interactions between the group XII metals Zn2+ and Cd2+ and amino acid residues play an important role in biology due to the prevalence of the first and the toxicity of the second. Estimates of the interaction energies between the ions and relevant residues in proteins are however difficult to obtain. This study reports on calculated interaction energy curves for small complexes of Zn2+ or Cd2+ and amino acid mimics (acetate, methanethiolate, and imidazole) or water. Given that many applications and models (e.g., force fields, solvation models, etc.) begin with and rely on an accurate description of gas-phase interaction energies, this is where our focus lies in this study. Four density functional theory (DFT)-functionals and MP2 were used to calculate the interaction energies not only at the respective equilibrium distances but also at a relevant range of ion–ligand separation distances. The calculated values were compared with those obtained by CCSD(T). All DFT-methods are found to overestimate the magnitude of the interaction energy compared to the CCSD(T) reference values. The deviation was analyzed in terms of energy components from localized molecular orbital energy decomposition analysis scheme and is mostly attributed to overestimation of the polarization energy. MP2 shows good agreement with CCSD(T) [root mean square error (RMSE) = 1.2 kcal/mol] for the eight studied complexes at equilibrium distance. Dispersion energy differences at longer separation give rise to increased deviations between MP2 and CCSD(T) (RMSE = 6.4 kcal/mol at 3.0 Å). Overall, the results call for caution in applying DFT methods to metalloprotein model complexes even with closed-shell metal ions such as Zn2+ and Cd2+, in particular at ion–ligand separations that are longer than the equilibrium distances.

  • 10.
    Ahlstrand, Emma
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Zukerman Schpector, Julio
    Universidade Federal de São Carlos, Brazil.
    Friedman, Ran
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Computer simulations of alkali-acetate solutions: Accuracy of the forcefields in difference concentrations2017In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 147, p. 1-10, article id 194102Article in journal (Refereed)
    Abstract [en]

    When proteins are solvated in electrolyte solutions that contain alkali ions, the ions interact mostlywith carboxylates on the protein surface. Correctly accounting for alkali-carboxylate interactionsis thus important for realistic simulations of proteins. Acetates are the simplest carboxylates thatare amphipathic, and experimental data for alkali acetate solutions are available and can be comparedwith observables obtained from simulations. We carried out molecular dynamics simulations of alkali acetate solutions using polarizable and non-polarizable forcefields and examined the ionacetateinteractions. In particular, activity coefficients and association constants were studied in a range of concentrations (0.03, 0.1, and 1M). In addition, quantum-mechanics (QM) based energy decomposition analysis was performed in order to estimate the contribution of polarization, electrostatics, dispersion, and QM (non-classical) effects on the cation-acetate and cation-water interactions. Simulations of Li-acetate solutions in general overestimated the binding of Li+ and acetates. In lower concentrations, the activity coefficients of alkali-acetate solutions were too high, which is suggested to be due to the simulation protocol and not the forcefields. Energy decomposition analysis suggested that improvement of the forcefield parameters to enable accurate simulations of Li-acetate solution scan be achieved but may require the use of a polarizable forcefield. Importantly, simulations with some ion parameters could not reproduce the correct ion-oxygen distances, which calls for caution in thechoice of ion parameters when protein simulations are performed in electrolyte solutions.

  • 11.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Difficulties associated with the formation of oxynitride glasses2014Conference paper (Refereed)
  • 12.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Formation and properties of nitrogen rich Ca-Si- (Al)-O-N glasses and Ceramics2014In: Conference proceeding 2014 Spring World Congress on Engineering and Technology, Shanghai, China (April 2014)., 2014, p. 59-59Conference paper (Refereed)
  • 13.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Properties of nitrogen rich mixed La-Pr silicon oxynitride glasses2014Conference paper (Refereed)
  • 14.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    J. Pomeroy, Michael
    University of Limerick, Ireland.
    Stuart, Hampshire
    University of Limerick, Ireland.
    Issues associated with the development of transparent oxynitride glasses2015In: Ceramics International, ISSN 0272-8842, E-ISSN 1873-3956, Vol. 41, no 3, p. 3345-3354Article in journal (Refereed)
    Abstract [en]

    Oxynitride glasses and glass ceramics are increasingly recognized as potential materials in specialist applications in modern industrial sectors. Oxynitride glasses have superior mechanical, rheological and optical properties to their oxide glass counterparts. Properties of these glasses can be tailored by changes in nitrogen content and additions of various alkaline-earth and or rare-earth elements. In contrast to oxide glasses, oxynitride glasses are difficult to prepare which adds to production costs. Furthermore, they contain impurities in the form of elemental silicon and silicides, have poor oxidation resistance in air above their glass transition temperatures and have poor transparency in the visible region. This article reviews the above issues in relation to the potential applications of these glasses.

  • 15.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Paul, Biplab
    Linköping University.
    Magnusson, Roger
    Linköping University.
    Greczynski, Grzegorz
    Linköping University.
    Broitman, Esteban
    Linköping University.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Eklund, Per
    Linköping University.
    Birch, Jens
    Linköping University.
    Novel transparent Mg-Si-O-N thin films with high hardness and refractive index2016In: Vacuum, ISSN 0042-207X, E-ISSN 1879-2715, Vol. 131, p. 1-4Article in journal (Refereed)
    Abstract [en]

    There is an increasing demand for glass materials with better mechanical and optical properties for display and electronic applications. This paper describes the deposition of novel thin films of Mg-Si-O-N onto float glass substrates. Amorphous thin films in the Mg-Si-O-N system with high nitrogen and magnesium contents were deposited by reactive RF magnetron co-sputtering from Mg and Si targets in Ar/N2/O2 gas mixtures. The thin films studied span an unprecedented range of compositions up to 45 at% Mg and 80 at% N out of cations and anions respectively. Thin films in the Mg-Si-O-N system were found to be homogeneous and transparent in the visible region. Mechanical properties like hardness (H) and reduced elastic modulus (Er) show high values, up to 21 GPa and 166 GPa respectively. The refractive index (1.87-2.00) increases with increasing magnesium and nitrogen contents.

  • 16.
    Allender, Chris J.
    et al.
    Cardiff University, UK.
    Andersson, Håkan S.
    University of Kalmar, School of Pure and Applied Natural Sciences. Cardiff University, UK.
    Brain, Keith R.
    Cardiff University, UK.
    Ramström, Olof
    Cardiff University, UK.
    Preface2001In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 435, no 1, p. 1-2Article in journal (Other academic)
  • 17.
    Alnehmry, Shaima
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Effektiviteten av läkemedelsbehandling för att minska muntorrhet och förebygga karies2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Dry mouth (xerostomia) is a common symptom which is connected with hypofunction of salivary glands induced by transient physiological conditions, pathology or as a side effect of drugs or radiation. Xerostomia almost always develops after destruction of salivary glands in connection with the treatment of head and neck cancer with ionizing radiation. Certain autoimmune diseases such as Sjogren's syndrome can also give dry mouth symptoms. The use of anticholinergic drugs and certain antihistamines may also cause a decrease in salivation. Aging is another factor that can induce salivary gland hypofunction due to physiological changes and/or use of medications. The treatment goals for patients with dry mouth is to relieve symptoms, prevent or ameliorate the consequences of salivary dysfunction, and treating the underlying disease. Treatments to improve function include saliva stimulation and saliva substitutes with fluoride. The systemic drugs bromhexine and pilocarpine are tested as saliva stimulants. Pilocarpine (Salagen) is a non-selective muscarinic agonist that increases the secretion of saliva.

    The purpose of this thesis was to investigate the effect of drug treatments to reduce dry mouth and prevent tooth decay, with the help of scientific articles.

    Results showed that in patients with some remaining unstimulated salivary flow rate daily treatments with a fluoride concentration of 0.42% F was enough to prevent tooth decay to a large extent. Use of 1.23% F-gel was not better than the 0.42% gel treatment. Casein derivatives complexed with calcium phosphate could be an alternative to fluoride treatment. Salivary secretion increased significantly after mouth rinse with 1% or 2% pilocarpine with a plateau between 45 and 75 minutes. 2% pilocarpine solution also increased the sense of salivary flow. Dry mouth was improved in 12.1; 63.6; 69.7 % of the patients who received Salagen tablets (5mg pilocarpine hydrochloride), 3mg or 5mg pilocarpine lozenge, respectively, compared with 42.4 % of patients receiving placebo lozenge. Mouth wash with pilocarpine 0.1% increased secretion from minor salivary glands and whole unstimulated saliva secretion compared to 0.9% saline mouthwash. The effectiveness in relieving subjective dry mouth was not significantly different between the solutions.

    Conclusions: Patients with unstimulated salivary flow <0.1 ml / min have a higher risk of caries lesions compared to unstimulated salivary flow> 0.1 ml / min. Patients with stimulated salivary flow <0.5 ml / min have a higher risk of caries lesions compared to stimulated salivary flow >0.5 ml / min. Mouthwash with pilocarpine solutions at concentrations of 1-2% pilocarpine induce a significant objective and subjective dose dependent increase in salivary flow. Pilocarpine lozenge produced the better clinical responses and a faster subjective improvement of dry mouth than Salagen tablets.

  • 18.
    Amann, Laura
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Development and Validation of an Analytical Method for Phenolic Acid Extraction from Cereals and Quantification using HPLC-UV2018Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Cereals are rich in phenolic acids, a group of secondary plant metabolites that are associated with reduced risk of chronic diseases. The objective was to develop and internally validate a method for extraction and quantification of phenolic acids in cereals using HPLC-UV and to apply this method for quantification of the content of phenolic acids in several species of Swedish cereals. Different procedures for extraction of phenolic acids from cereal grains using acid or base hydrolysis with and without subsequent enzymatic treatment were tested. Both the extraction procedure and the chromatographic conditions for quantification with HPLC-UV were optimized. Phenolic acids from 14 cereal samples, representing different cultivars of rye, wheat, barley, and oat, were extracted and analyzed under optimized conditions. Using the optimized method, 15 phenolic acids could be quantified with limits of detection and quantification ranging from 0.4 to 11.4 µg/g and from 1.3 to 38.0 µg/g, respectively. The hydrolysis procedure and further sample treatment showed a substantial effect on the yield of phenolic acids from cereals. The highest yield was achieved by 90‑minute base hydrolysis at room temperature using sodium hydroxide solution containing ascorbic acid and EDTA. Mean recoveries ranged from 88 to 108%. The following phenolic acids were found in the analyzed cereal grains with ferulic acid being the most abundant one: p‑hydroxybenzoic acid, vanillic acid, vanillin, caffeic acid, syringic acid, ferulic acid, sinapic acid, and 3,4‑dihydroxybenzaldehyde. A further compound was p‑coumaric acid or the co‑eluting syringaldehyde or a mixture of both. The content of phenolic acids in Swedish cereals ranged from 6 µmol/g DM in rye to 3 µmol/g DM in oat and a barley cultivar. In conclusion, a simple and accurate method for extraction and quantification of phenolic acids in cereals was developed and successfully applied.

  • 19. Anderbrant, Olle
    et al.
    Matteson, Donald S.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Pharazyn, Philip S
    Santangelo, Ellen M.
    Schlyter, Fredrik
    Birgersson, Göran
    Pheromone of the elm bark beetle Scolytus laevis (Coleoptera: Scolytidae): stereoisomers of 4-methyl-3-heptanol reduce interspecific competition2010In: Chemoecology, ISSN 0937-7409, E-ISSN 1423-0445, Vol. 20, no 3, p. 179-187Article in journal (Refereed)
    Abstract [en]

    Stereoisomers of 4-methyl-3-heptanol (MH) are pheromone components of several Scolytus bark beetles. The elm bark beetle Scolytus laevis (Coleoptera: Scolytidae) has in previous studies been caught in traps baited with commercial MH containing all four stereoisomers, but the lure has been considered a weak attractant. In this study, we addressed the question whether stereospecific responses by S. laevis to stereoisomers of MH might contribute to its niche separation from other sympatric Scolytus species. Using GC–MS, we analyzed extracts of hindguts and abdomens from male and female S. laevis and the sympatric S. triarmatus. We also tested all four MH-stereoisomers individually and in combinations in the field to determine their role for S. laevis. All four stereoisomers were synthesized via a boronic ester method with 1,2-dicyclohexylethanediol as chiral director. In addition, the (3S,4R)-stereoisomer of MH was prepared through enantioselective, lipase-mediated transesterification of a mixture of the four stereoisomers of MH. Females of both species contained small amounts of syn-MH, and males contained trace amounts of anti-MH. The anti stereoisomer (3R,4S)-MH was attractive to male and female S. laevis, whereas the syn stereoisomer (3S,4S)-MH acted as an inhibitor or deterrent and reduced the catch when added to the attractive isomer. The syn isomer is the main aggregation pheromone component of the larger and sympatric S. scolytus and possibly also of S. triarmatus. The avoidance response of S. laevis to the (3S,4S)-stereoisomer may reduce interspecific competition for host trees.

  • 20.
    Andersson, Fredrik
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Studies on organic liquid baby-food gruel: The effect of including organic flour and starch from corn2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: Studies conducted on foods aimed for infants and young children have shown that foods containing rice have a high content of arsenic and cadmium. Arsenic and cadmium are toxic elements classified as carcinogens. It is therefore especially important to keep the levels low in foods for infants and young children since they have a high intestinal absorption and since the negative effects become apparent only after many years of chronic exposure.

    Aim: The aim of this project was to investigate if the rice flour in baby-food gruel could be replaced with corn flour with the aim to decrease the content of primarily arsenic and cadmium and sustain low levels of lead and mercury while retaining sensory properties. A native corn starch was also evaluated in terms of heavy metal content and sensory properties.

    Material & Methods: The rice flour in 4 different recipes was replaced with various proportions of flour and starch from corn whereon sensory evaluations were performed. Stability and viscosity measurements were conducted and the content of arsenic, cadmium, lead and mercury was analysed.

    Results/Conclusion: No differences in texture and mouth feel could be perceived at low corn flour concentrations when mixed with rice flour. Replacement of 60% of the rice flour fraction with corn flour in a gruel which contained 1.1% rice flour (w/w), may have led to an increased arsenic content. The corn starch provided the highest viscosity and had a smoother mouth feel at the same concentration compared to the corn flour and might be a better choice than the corn flour. In addition, corn starch had a lower content of cadmium and lead compared to the corn flour but further research is needed to establish which one contains the lowest level of arsenic. Both had a lower content of arsenic compared to the rice flour when the flours were analysed separately.

  • 21.
    Andersson, Håkan S.
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Figueredo, Sharel M.
    Haugaard-Kedström, Linda M.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Bengtsson, Elina
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Daly, Norelle L.
    Qu, Xiaoqing
    Craik, David J.
    Ouellette, Andre J.
    Rosengren, K. Johan
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    The alpha-defensin salt-bridge induces backbone stability to facilitate folding and confer proteolytic resistance2012In: Amino Acids, ISSN 0939-4451, E-ISSN 1438-2199, Vol. 43, no 4, p. 1471-1483Article in journal (Refereed)
    Abstract [en]

    Salt-bridge interactions between acidic and basic amino acids contribute to the structural stability of proteins and to protein-protein interactions. A conserved salt-bridge is a canonical feature of the alpha-defensin antimicrobial peptide family, but the role of this common structural element has not been fully elucidated. We have investigated mouse Paneth cell alpha-defensin cryptdin-4 (Crp4) and peptide variants with mutations at Arg(7) or Glu(15) residue positions to disrupt the salt-bridge and assess the consequences on Crp4 structure, function, and stability. NMR analyses showed that both (R7G)-Crp4 and (E15G)-Crp4 adopt native-like structures, evidence of fold plasticity that allows peptides to reshuffle side chains and stabilize the structure in the absence of the salt-bridge. In contrast, introduction of a large hydrophobic side chain at position 15, as in (E15L)-Crp4 cannot be accommodated in the context of the Crp4 primary structure. Regardless of which side of the salt-bridge was mutated, salt-bridge variants retained bactericidal peptide activity with differential microbicidal effects against certain bacterial cell targets, confirming that the salt-bridge does not determine bactericidal activity per se. The increased structural flexibility induced by salt-bridge disruption enhanced peptide sensitivity to proteolysis. Although sensitivity to proteolysis by MMP7 was unaffected by most Arg(7) and Glu(15) substitutions, every salt-bridge variant was degraded extensively by trypsin. Moreover, the salt-bridge facilitates adoption of the characteristic alpha-defensin fold as shown by the impaired in vitro refolding of (E15D)-proCrp4, the most conservative salt-bridge disrupting replacement. In Crp4, therefore, the canonical alpha-defensin salt-bridge facilitates adoption of the characteristic alpha-defensin fold, which decreases structural flexibility and confers resistance to degradation by proteinases.

  • 22.
    Andersson, Håkan S.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Jacobsson, Erik
    Uppsala University.
    Eriksson, Camilla
    Uppsala University.
    Hedström, Martin
    Lund University.
    Seth, Henrik
    University of Gothenburg.
    McEvoy, Eric G
    Liverpool John Moores University.
    Sundberg, Per
    University of Gothenburg.
    Strand, Malin
    Swedish University of Agricultural Sciences.
    Göransson, Ulf
    Uppsala University.
    Discovery of peptide toxins in ribbon worms: challenging claims of tetrodotoxin production2015Conference paper (Other academic)
  • 23.
    Andersson, Håkan S.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Jacobsson, Erik
    Uppsala University.
    Eriksson, Camilla
    Uppsala University.
    Rosengren, K. Johan
    University of Queensland, Australia.
    Andrén, Per
    Uppsala University.
    Strand, Malin
    Swedish agricultural university (SLU).
    Göransson, Ulf
    Uppsala University.
    Discovery of peptide toxins in the bootlace worm, the world's longest animal2015Conference paper (Other academic)
  • 24.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Karlsson, Jesper G.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Piletsky, S A
    Koch-Schmidt, Ann-Christin
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Mosbach, K
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Influence of monomer-template ratio on selectivity and load capacity of molecularly imprinted polymers: indications of template self-association1999In: Journal of Chromatography A, Vol. 848, no 1-2, p. 39-49Article in journal (Refereed)
  • 25.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Karlsson, Jesper G.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Svenson, Johan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Can template-template self-association contribute to polymer-ligand recognition characteristics?2000Conference paper (Refereed)
  • 26.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Koch-Schmidt, Ann-Christin
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ohlson, Sten
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Study of the Nature of Recognition in Molecularly Imprinted Polymers1996In: J. Mol. Recogn., Vol. 9, p 675-682Article in journal (Refereed)
  • 27.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Koch-Schmidt, Ann-Christin
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ohlson, Sten
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Mosbach, Klaus
    Lund University.
    Study of Weak Affinity Interactions in Molecularly Imprinted Polymers1995In: Journal of Molecular Recognition, ISSN 0952-3499, E-ISSN 1099-1352, Vol. 8, no 3, p. 231-Article in journal (Other academic)
  • 28.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Molecular Imprinting. Recent innovations in synthetic polymer receptor and enzyme mimics1997In: Recent Research Developments in Pure and Applied Chemistry, Vol. 1, p. 133-157Article in journal (Refereed)
  • 29.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Spectroscopic evaluation of molecular imprinting polymerization systems1997In: Bioorganic Chemistry, Vol. 25, p. 203-211Article in journal (Refereed)
  • 30.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    The development of molecular imprinting2000Other (Other academic)
  • 31.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Piletsky, S A
    Mosbach, K
    Koch-Schmidt, Ann-Christin
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Novel recognition elements for improved molecularly imprinted polymer stereoselectivity1997Conference paper (Refereed)
  • 32.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences. Cranfield University, UK.
    Piletsky, Sergey A
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Mosbach, Klaus
    Lund University.
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Koch-Schmidt, Ann-Christin
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Cooperative Binding in Molecularly Imprinted Polymers against (-)-Nicotine.1997Conference paper (Other academic)
  • 33.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ramström, O
    Crown Ethers as a Tool for the Preparation of Molecularly Imprinted Polymers1998In: Journal of Molecular Recognition, Vol. 11, p. 103-106Article in journal (Refereed)
  • 34.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ramström, Olof
    Lund University.
    Crown ethers as a tool for the preparation of molecularly imprinted polymers1997Conference paper (Other academic)
  • 35. Andersson, L I
    et al.
    Nicholls, Ian Alan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Mosbach, K
    Immunoassays using molecularly imprinted polymers1995In: Immunoanalysis of agrochemicals: emerging technologies / [ed] Judd O. Nelson, Alexander E. Karu and Rosie B. Wong, American Chemical Society (ACS), 1995, p. 89-97Conference paper (Other academic)
  • 36.
    Andreasson, Johan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Emissioner av flyktiga organiska föreningar från vattenburna lacker2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Arbetet har jämfört de emissioner som olika tjocklek på lacklagren samt olika torkningstemperaturer ger upphov till. Det konstaterades att tjocka lager ger upphov till oproportionerligt höga emissioner både på kort och framförallt på lång sikt. En högre torkningstemperatur orsakar lägre emissioner på kort sikt men lika höga eller högre på lång sikt. Inverkan från underlaget som lacken applicerades på undersöktes också och där konstaterades att ett porösare medium, i detta fall en MDF-skiva, orsaker lägre emissioner. Sannolikt pga att ämnena sugs upp av materialet. Den tredje delen bestod i att jämföra olika testkammares förmåga att registrera de sökta ämnena. Två stycken kammare med volymen 1m3 och en liten kammare med volymen 3ml användes. Det visade sig att de båda stora kamrarna visade liknande resultat om tiden efter att lacken applicerats på proverna var densamma. Den mindre visade klart lägre koncentrationer i försöksluften men omräknat till ytspecifik utsöndring var värdena jämförbara. Ämnen med hög kokpunkt var överrepresenterade i den lilla kammaren och ämnen med låg kokpunkt underrepresenterade, vilket gör att kammaren lämpar sig bäst för jämförande studier.

  • 37.
    Ankarloo, Jonas
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Wikman, Susanne
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Nicholls, Ian A.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Escherichia coli mar and acrAB Mutants Display No Tolerance to Simple Alcohols2010In: International Journal of Molecular Sciences, ISSN 1422-0067, E-ISSN 1422-0067, Vol. 11, no 4, p. 1403-1412Article in journal (Refereed)
    Abstract [en]

    The inducible Mar phenotype of Escherichia coli is associated with increased tolerance to multiple hydrophobic antibiotics as well as some highly hydrophobic organic solvents such as cyclohexane, mediated mainly through the AcrAB/TolC efflux system. The influence of water miscible alcohols ethanol and 1-propanol on a Mar constitutive mutant and a mar deletion mutant of E. coli K-12, as well as the corresponding strains carrying the additional acrAB deletion, was investigated. In contrast to hydrophobic solvents, all strains were killed in exponential phase by 1-propanol and ethanol at rates comparable to the parent strain. Thus, the Mar phenotype does not protect E. coli from killing by these more polar solvents. Surprisingly, AcrAB does not contribute to an increased alcohol tolerance. In addition, sodium salicylate, at concentrations known to induce the mar operon, was unable to increase 1-propanol or ethanol tolerance. Rather, the toxicity of both solvents was increased in the presence of sodium salicylate. Collectively, the results imply that the resilience of E. coli to water miscible alcohols, in contrast to more hydrophobic solvents, does not depend upon the AcrAB/TolC efflux system, and suggests a lower limit for substrate molecular size and functionality. Implications for the application of microbiological systems in environments containing high contents of water miscible organic solvents, e. g., phage display screening, are discussed.

  • 38. Aveyard,, J
    et al.
    Hajne, J.
    Månsson, Alf
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Persson, Malin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    van Delft,, F.C.M.J.M.
    van Zijl, J.
    Snijder, J.
    van den Heuvel,, F.C.
    Nicolau,, D.V.
    Actin motility confinement on micro/nanostructured surfaces.2013In: Proc. SPI 8587, Imaging, Manipulation, and Analysis of Biomolecules, Cells, and Tissues XI, 858722 (February 22, 2013) / [ed] Daniel L. Farkas; Dan V. Nicolau; Robert C. Leif, SPIE - International Society for Optical Engineering, 2013, p. 858722-858727Conference paper (Refereed)
  • 39.
    Becconi, Olga
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. University of Cagliari, Italy.
    Ahlstrand, Emma
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Salis, Andrea
    University of Cagliari, Italy.
    Friedman, Ran
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Protein-ion Interactions: Simulations of Bovine Serum Albumin in Physiological Solutions of NaCl, KCl and LiCl2017In: Israel Journal of Chemistry, ISSN 0021-2148, Vol. 57, no 5, p. 403-412Article in journal (Refereed)
    Abstract [en]

    Specific interactions that depend on the nature of electrolytes are observed when proteins and other molecules are studied by potentiometric, spectroscopic and theoretical methods at high salt concentrations. More recently, it became clear that such interactions may also be observed in solutions that can be described by the Debye-Hückel theory, i.e., at physiological (0.1 mol dm−3) and lower concentrations. We carried out molecular dynamics simulations of bovine serum albumin in physiological solutions at T=300 and 350 K. Analysis of the simulations revealed some differences between LiCl solutions and those of NaCl and KCl. The binding of Li+ ions to the protein was associated with a negative free energy of interaction whereas much fewer Na+ and K+ ions were associated with the protein surface. Interestingly, unlike other proteins BSA does not show a preference to Na+ over K+. Quantum chemical calculations identified a significant contribution from polarisation to the hydration of Li+ and (to a lesser degree) Na+, which may indicate that polarisable force-fields will provide more accurate results for such systems.

  • 40.
    Bergecliff, Terese
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Viscosity and Acid Stability in Low-fat Mayonnaise with Varying Proportions of Xanthan Gum and Guar Gum2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Mayonnaise is a mixture of egg yolk, vinegar, water, spices and 70-80% oil forming a semi-solid oil-in-water emulsion. When preparing a low-fat mayonnaise with an increased water content, thickening agents are required for increased viscosity and emulsion stability. The hydrocolloids xanthan gum and guar gum are sometimes used for this purpose and they act synergistically creating a viscosity increase. However, guar gum has poor acid stability, and because mayonnaise is an acidic product guar gum will eventually start to degrade causing a viscosity decrease and subsequent emulsion separation. Despite this fact, guar gum and xanthan gum are extensively used in mayonnaises today.

    The aim of this degree project was to explore how the synergy between guar gum and xanthan gum influences the viscosity of a low fat mayonnaise and whether high acidity will have an impact on the viscosity over a 4-week period. This was to examine if and if so, how a mayonnaise recipe can be modified to maintain a cost efficient product with the desired rheological properties in times of hydrocolloid price fluctuations. The study was conducted by preparing 15 mayonnaises with 50% fat, either at pH 3,5; 4 or 5 and a total of 0,6 % hydrocolloids with varying proportions of guar gum and xanthan gum. The mayonnaise samples were studied by measurements of viscosity, color changes and a visual comparison of their mayonnaise-like flow-properties compared to Hellmann’s Real Mayonnaise used as reference.

    The viscosity of the mayonnaises increased with increasing ratio of guar gum. On the other side, there were greater viscosity losses in mayonnaises with increasing ratio of guar gum 4 weeks after preparation compared to 4 days, with no apparent signs of correlation between higher acidity and hydrocolloid degradation. Mayonnaises with 20% xanthan gum and 80% guar gum had the texture most similar to the reference. In these low-fat mayonnaises, the use of more xanthan gum led to an undesired “slimy” texture and a lower viscosity – an important aspect if adjusting a low-fat mayonnaise recipe by increasing the ratio of xanthan gum. Because a commercial mayonnaise sometimes is consumed several months after manufacturing, that time frame is most likely required in order to fully measure how much the high acidity in mayonnaise will affect its viscosity. This project has shown a pattern where viscosity in the assessed mayonnaises starts to decrease a few weeks after preparation. However to find out exactly to what extent and how this would affect the overall product, and ultimately: if guar gum/xanthan gum combinations are suitable for long-term mayonnaise applications, further studies are required. 

  • 41.
    Bergsell, Philip
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Karakterisering av mikroalger och återvinning av biprodukter2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 42.
    Bergström, Maria
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Ganji, Suresh
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Naidu Veluru, Ramesh
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    N-Iodosuccinimide (NIS) in Direct Aromatic Iodination2017In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 22, p. 3234-3239Article in journal (Refereed)
    Abstract [en]

    N-Iodosuccinimide (NIS) in pure trifluoroacetic acid (TFA) offers a time-efficient and general method for the iodination of a wide range of mono-and disubstituted benzenes at room temperature, as demonstrated in this paper. The starting materials were generally converted into mono-iodinated products in less than 16 hours at room temperature, without byproducts. A few deactivated substrates needed addition of sulfuric acid to increase the reaction rate. Another exception was methoxybenzenes that preferentially were iodinated by NIS in acetonitrile with only catalytic amounts of TFA.

  • 43.
    Bergström, Maria
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Åström, Eva
    Påhlsson, Peter
    Ohlson, Sten
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Elucidating the selectivity of recombinant forms of Aleuria aurantia lectin using weak affinity chromatography2012In: Journal of chromatography. B, ISSN 1570-0232, E-ISSN 1873-376X, Vol. 885-886, p. 66-72Article in journal (Refereed)
    Abstract [en]

    Aberrant glycosylation is connected to several pathological conditions and lectins are useful tools to characterize glycosylated biomarkers. The Aleuria aurantia lectin (AAL) is of special interest since it interacts with all types of fucosylated saccharides. AAL has been expressed in E.coli as a fully functional recombinant protein. Engineered variants of AAL have been developed with the aim of creating monovalent lectins with more homogenous binding characteristics. Four different forms of AAL were studied in the present work: native AAL purified from Aleuria aurantia mushrooms, recombinant AAL dimer, recombinant AAL monomer and recombinant AAL site 2 (S2-AAL). The affinities of these AAL forms towards a number of saccharides were determined with weak affinity chromatography (WAC). Disaccharides with fucose linked α1-3 to GlcNAc interacted with higher affinity compared to fucose linked α1-6 or α1-4 and the obtained dissociation constants (Kd) were in the range of 10 μM for all AAL forms. Tetra- and pentasaccharides with fucose in α1-2, α1-3 or α1-4 had Kd values ranging from 0.1–7 mM while a large α1-6 fucosylated oligosaccharide had a Kd of about 20 μM. The recombinant multivalent AAL forms and native AAL exhibited similar affinities towards all saccharides, but S2-AAL had a lower affinity especially regarding a sialic acid containing fucosylated saccharide. It was demonstrated that WAC is a valuable technique in determining the detailed binding profile of the lectins. Specific advantages with WAC include a low consumption of non-labeled saccharides, possibility to analyze mixtures and a simple procedure using standard HPLC equipment.

  • 44.
    Bhhatarai, Barun
    et al.
    University of Insubria, Italy.
    Teetz, Wolfram
    German Research Center for Environmental Health, Germany.
    Liu, Tao
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Öberg, Tomas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Jeliazkova, Nina
    Ideaconsult Ltd, Bulgaria.
    Kochev, Nikolay
    University of Plovdiv, Bulgaria.
    Pukalov, Ognyan
    University of Plovdiv, Bulgaria.
    Tetko, Igor
    German Research Center for Environmental Health, Germany.
    Kovarich, Simona
    University of Insubria, Italy.
    Papa, Ester
    University of Insubria, Italy.
    Gramatica, Paola
    University of Insubria, Italy.
    CADASTER QSPR Models for Predictions of Melting and Boiling Points of Perfluorinated Chemicals2011In: Molecular Informatics, ISSN 1868-1751, Vol. 30, no 2-3, p. 189-204Article in journal (Refereed)
    Abstract [en]

    Quantitative structure property relationship (QSPR) studies on per- and polyfluorinated chemicals (PFCs) on melting point (MP) and boiling point (BP) are presented. The training and prediction chemicals used for developing and validating the models were selected from Syracuse PhysProp database and literatures. The available experimental data sets were split in two different ways: a) random selection on response value, and b) structural similarity verified by self-organizing-map (SOM), in order to propose reliable predictive models, developed only on the training sets and externally verified on the prediction sets. Individual linear and non-linear approaches based models developed by different CADASTER partners on 0D-2D Dragon descriptors, E-state descriptors and fragment based descriptors as well as consensus model and their predictions are presented. In addition, the predictive performance of the developed models was verified on a blind external validation set (EV-set) prepared using PERFORCE database on 15 MP and 25 BP data respectively. This database contains only long chain perfluoro-alkylated chemicals, particularly monitored by regulatory agencies like US-EPA and EU-REACH. QSPR models with internal and external validation on two different external prediction/validation sets and study of applicability-domain highlighting the robustness and high accuracy of the models are discussed. Finally, MPs for additional 303 PFCs and BPs for 271 PFCs were predicted for which experimental measurements are unknown.

  • 45.
    Bjarnason, Bjarni
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Datorstött lärande på gymnasieskolan inom naturvetenskapliga ämnen: med speciell betoning på kemididaktiken.2006Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Elever upplever allt som oftast svårigheter med den naturvetenskapliga undervisningen som ofta upplevs som abstrakt och overklig. De förklaringsmodeller som har beskrivits kring detta är att eleverna har svårigheter med att växla mellan makro (det man ser med ögat) och mikro (molekylär värld). I flera publikationer har man kunnat visa att för att nå en bred publik bör man aktivera så många sinnen som möjligt vilket är det som jag tar fasta på i detta arbete. Datormedierad multimedia framställning i undervisningen har, i publikationer, visat sig kunna kan skapa en bättre förståelse hos elever i kemi. Framförallt är det datorgenererad media framställning som simultant kan presenterar kemiska förlopp med olika representationer som har visat sig ge bra resultat. I denna studie har man kunnat visa att elever är mycket positiva till denna typ av framställning där man kan utföra experiment och se animeringar. De menar också själva att detta underlättar förståelsen av den molekylära världen. Genom att studera fall och kontroll kunde man även i denna studie visa på vissa skillnader i elevers kunskaper. De elever som fick möjlighet att studera animeringar och göra virtuella laborationer hade något bättre resultat än de som inte fick denna möjlighet.

  • 46.
    Bjenning, Lovisa
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Implementation of improved fat standardization using statistical process control2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this project was to apply statistical process control (SPC) and measure the variation of fat content in milk in order to improve the standardization, so that the fat content does not change more than 0.03 percentage units from target. Recommendations of how to adjust the standardization should also be developed. The standardization takes place together with pasteurization in one of the three pasteurizers. Thereafter, the milk goes to a common product tank with all the pasteurizers. Samples from the three pasteurizers and the product tank were collected and analyzed on MilkoScan FT2 and the fat content was plotted into Shewhart and cumulative sum (CUSUM) charts. Sampling on the pasteurizers from startup showed that samples should be taken after about 20 minutes, because then the variation is in general smaller. The data from the product tank showed a smaller variation than the pasteurizers. Because the milk from all the pasteurizers is transported into one product tank, it is impossible to know which pasteurizer that is out of control and need to be adjusted. Therefore, the conclusion is that samples should be taken after the pasteurizer and plotted into Shewhart and CUSUM charts. Action limits were achieved from the Shewhart and CUSUM charts, respectively. These are the limits that should be used to determine when adjustments of the pasteurizers are needed, and not the brand limits that are considerably wider. If the measurements fall outside the second limit in the Shewhart chart (three times the standard deviation) or outside the limits (H) in the CUSUM chart, the standardization before the pasteurizer in question should be considered. It is not known if using SPC will improve the fat content to be within 0.03 percent units from target, because the recommendation has not been applied in the process yet, but it going to be that soon.

  • 47. Bohman, B
    et al.
    Nordlander, G
    Nordenhem, H
    Sunnerheim, K
    Borg-Karlson, A-K
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Structure - activity relationships of phenyl propanoids as antifeedants for the pine weevil Hylobius abieist2008In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 34, no 3, p. 339-352Article in journal (Refereed)
  • 48.
    Bohman, Björn
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Cavonius, Lillie
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Unelius, C. Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Vegetables as biocatalysts in stereoselective hydrolysis of labile organic compounds2009In: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 11, no 11, p. 1900-1905Article in journal (Refereed)
    Abstract [en]

    Hydrolysis of labile esters of beta-hydroxyketones has been performed with whole plant tissue from various vegetables. The pheromone 5-hydroxy-4-methyl-3-heptanone (1) was used as the model compound. Hydrolysis of acetates and benzoates of 1 was unsuccessful using normal conditions of ester hydrolysis, both by chemical hydrolysis and by the means of commercial lipases. When, however, whole cells of carrot, celery root, eggplant, parsley root, parsnip and potato were used as reagents, hydrolysis of the acetates was successful. At low conversion the hydrolysis was stereoselective and at total conversion virtually no formation of by-products was observed. The selectivity varied among the eight vegetables that were evaluated. Methods of preparation and substrate-to-plant ratio were examined. Furthermore, acetates and benzoates of three analogous compounds [5-hydroxy-3-heptanone (2), 5-hydroxy-5-methyl-3-heptanone (3) and 5-ethyl-6-hydroxy-4-octanone (4)] were hydrolyzed by potato and sweet potato to various degrees, indicating that the method is general for the mild and stereoselective hydrolysis of secondary beta-alkoxy-and beta-aryloxyketones.

  • 49.
    Bohman, Björn
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Troger, A.
    University of Hamburg.
    Franke, S.
    University of Hamburg.
    Lorenzo, M. G.
    Fiocruz, Belo Horizonte, Brazil.
    Francke, W.
    University of Hamburg.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Structure Elucidation and Synthesis of Dioxolanes Emitted by Two Triatoma Species (Hemiptera Reduviidae)2011In: Journal of natural products (Print), ISSN 0163-3864, E-ISSN 1520-6025, Vol. 74, no 4, p. 690-694Article in journal (Refereed)
    Abstract [en]

    Volatiles from the metastemal glands of two species Of true bugs of the Triatominae subfamily, Triatoma brasiliensis and Triatoma infestans, Were analyzed by SPME-GC/MS. Two sets of new natural products were found: (4S,5S)- and (4R,SR)-2,2,4-triethyl-5-methyl-1,3-dioxolane (1) (major component) and (45*,5S*)-2,4-diethyl-2,S-dimethyl-1,3-dioxolane (2) (trace component),-,(2R/S,4S,SS)- as well as (2R/S,4R,5R)-4-ethyl-5-methyl-2-(1-methylethyl)-1,3-dioxolane (3) (minor component), (2R/S,4S*,5S*).-4-ethyl-5-methyl-2-(1-methylpropyl)-1,3-dioxolane (4), (trace component), and (2R/S,4S*,5S*)-4-ethyl-5-methyl-2-(2-methylpropyl)-1,3-dioxolane (5) (trace component). Syntheses of optically active 1 and 3 were carried out by reacting pure,enantiomers of 2,3-pentanediol with 3-pentanone or 2-methylpropanal. The preparation of, pure 1 stereoisomers of 2,3-pentanediol involved a novel key step for the synthesis of secondary alcohols: the reduction of a carboxylic ester by means of DIBAH and in situ alkylation of the intermediate by Grignard reaction at low temperature Starting from the pure enantiomers of methyl lactate; all four stereoisoniers of 2,3-pentanediol were synthesized. and transformed, to the corresponding isomers of 1 and 2. Relative configurations of the natural products and enantiomeric compositions of naturally occurring 1 and :2 were determined by comparison of their mass spectra and gas chromatographic retention times (co-injection) I with those of authentic reference samples.

  • 50.
    Bohman, Björn
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Unelius, C. Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Synthesis of all four stereoisomers of 5-hydroxy-4-methyl-3-heptanone using plants and oyster mushrooms2009In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 65, no 42, p. 8697-8701Article in journal (Refereed)
    Abstract [en]

    All four possible stereoisomers of 5-hydroxy-4-methyl-3-heptanone were synthesized from common achiral reagents using fast, straightforward organic synthesis, including the use of whole tissue of Daucus carota, Solanum melongena, and Pleurotus ostreatus.

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