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  • 1. Anderbrant, O
    et al.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Pheromone mating disruption of the pine sawfly Neodiprion sertifer.: Is the size of the area important?2002In: IOBC/WPRS Bulletin, ISSN 1027-3115, Vol. 25, no 9, p. 111-116Article in journal (Other scientific)
    Abstract [en]

    The success of mating disruption in relation to the area treated is discussed

  • 2. Anderbrant, O
    et al.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Löfqvist, J
    Towards use of Pine Sawfly Pheromones in Forest Protection: Evalution of a Behavioural Antagonist for Mationg Disruption of Neodiprion sertifer1998In: Population Dynamics, Impacts and Integrated Management of Forest Defoliating Insects, 1998, p. 53-63Conference paper (Refereed)
  • 3. Anderbrant, O
    et al.
    Löfqvist, E
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Development of mating disruption for control of pine sawfly populations1995In: Entomologia Experimentalis et Applicata, ISSN 0013-8703, Vol. 74, no 1, p. 83-90Article in journal (Refereed)
  • 4. Anderbrant, O
    et al.
    Löfqvist, J
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Baldassari, N
    Baronio, P
    Kolmakova, G
    Lyons, B
    Naito, T
    Odinokov, V
    Simandl, J
    Suptashvili, A
    Tai, A
    Tourianov, R
    Geographic Variation in the Field Response of Male Pine Sawflies Neodiprion sertifer, to Different Pheromone Stereoisomers and Esters2000In: Entomologia Experimentalis et Applicata, ISSN 0013-8703, E-ISSN 1570-7458, Vol. 95, no 3, p. 229-239Article in journal (Refereed)
  • 5. Anderbrant, O
    et al.
    Löfqvist, J
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Wassgren, A.-B.
    Bergström, G
    Bengtsson, M
    Magnusson, G
    Field Response Of The Pine Sawfly Neodiprion-Sertifer To The Pheromone (2s,3s,7s)-Diprionyl Acetate And Its Stereoisomers1992In: Entomologia Experimentalis et Applicata, ISSN 0013-8703, Vol. 62, no 2, p. 169-181Article in journal (Refereed)
  • 6. Anderbrant, Olle
    et al.
    Lyons, D. Barry
    Bång, Joakim
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Sex Pheromone of the Introduced Pine Sawfly, Diprion similis (Diprionidae), Revisited: No Activity of Earlier Reported SynergistsManuscript (preprint) (Other academic)
    Abstract [en]

    Extracts of Diprion similis females were found to contain about 15 ng of the sex pheromone precursor 3,7-dimethylpentadecan-2-ol per female. When analysing the extracts after derivatisation with (2S)-2-acetoxypropionyl chloride, we found that the major stereoisomer in the extract was (2S,3R,7R)-3,7-dimethylpentadecan-2-ol. Also other stereoisomers of 3,7-dimethylpentadecan-2-ol were identified in the extract namely, 1% of (2R,3S,7S) , 0.3% (2R,3R,7R) and 0.4% of (2R,3R,7S). An unknown fifth substance showed an identical spectrum to 3,7-dimethylpentadecan-2-ol, both in SIM and full scan mode. In field tests in Ontario, Canada, the earlier identified main pheromone component, viz. the propanoate of (2S,3R,7R)-3,7-dimethylpentadecan-2-ol, was tested alone and in combination with other stereoisomers, earlier reported to be synergistic. In none of the tests were any synergistic effects detected and the threo four-isomer blend was as attractive as the pure main compound. Thus, one of the few examples of a diprionid sawfly using more than one substance in its sex pheromone could not be confirmed. The results also suggest that monitoring programs can use the more easily synthesized threo-blend without losing efficiency.

  • 7. Anderbrant, Olle
    et al.
    Löfqvist, J
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Mating disruption of the Pine Sawfly Neodiprion sertifer (Hymenoptera: Dipionidae): Effects on Pheromone Trap Catch, Sex Ratio, Population Density and Tree Damage1995In: Behavior, population dynamics, and control of forest insects: Proceedings of the International Union of Forestry Research Organizations Joint conference, February 1994, 1995, p. 415-427Conference paper (Refereed)
  • 8.
    Anderbrant, Olle
    et al.
    Department of Biology, Lund University.
    Löfqvist, Jan
    Department of Plant Protection Science, Swedish University of Agricultural Sciences, Alnarp.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Bång, Joakim
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Tai, Akira
    Faculty of Science, Himeji Institute of Technology, Kanaji Kamigor, Japan.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Field Response of Male Pine Sawflies, Neodiprion sertifer (Diprionidae), to Sex Pheromone Analogs in Japan and Sweden2010In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 36, no 9, p. 969-977Article in journal (Refereed)
    Abstract [en]

    The pine sawfly Neodiprion sertifer (Geoffroy) uses the acetate or propionate of (2S,3S,7S)-3,7-dimethyl-2-pentadecanol (diprionol) as pheromone components, with the (2S,3R,7R)-isomer being antagonistic, synergistic, or inactive according to the population tested. In this study, we tested the attraction of males to the acetates of three analogs of diprionol, each missing one methyl group, viz. (2S,7S)-7-methyl-2-pentadecanol, (2S,6S)-2,6-dimethyl-1-tetradecanol, and (2S,3S)-3-methyl-2-pentadecanol. None of the analogs alone, or in combination with diprionol acetate, was attractive in Sweden, even at 100 times the amount of diprionol acetate attractive to N. sertifer. In Japan, the acetate of (2S,3S)-3-methyl-2-pentadecanol attracted males when tested in amounts 10–20 times higher than the acetate pheromone component. The acetate esters of the (2S,3R)-analog and the (2S,3R,7R)-isomer of diprionol also were tested in combination with the pheromone compound (acetate ester). Both compounds caused an almost total trap-catch reduction in Sweden, whereas in Japan they appear to have relatively little effect on trap capture when added to diprionol acetate. Butyrate and iso-butyrate esters of diprionol were unattractive to N. sertifer in Sweden. In summary, there exists geographic variation in N. sertifer in responses to both diprionyl acetate and some of its analogs.

  • 9. Anderbrant, Olle
    et al.
    Östrand, Fredrik
    Bergström, Gunnar
    Wassgren, Ann-Britt
    Auger-Rozenberg, Marie-Anne
    Geri, Claude
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Release of sex pheromone and its precursors in the pine sawfly Diprion pini (Hym., Diprionidae)2005In: Chemoecology, ISSN 0937-7409, E-ISSN 1423-0445, Vol. 15, no 3, p. 147-151Article in journal (Refereed)
    Abstract [en]

    The first identification of a sex pheromone of a pine sawfly (Hymenoptera, Diprionidae) dates back almost thirty years. Since then, female-produced pheromones of over twenty diprionid species have been investigated by solvent extraction followed by separation and identification. However, no study has shown what the females actually release. Collection of airborne compounds using absorbtion on charcoal filter as well as solid phase microextraction (SPME) followed by analysis employing gas chromatography combined with mass spectrometry (GC-MS), revealed an unusual system in Diprion pini, in which the pheromone precursor alcohol, 3,7-dimethyl-2-tridecanol, is released together with acetic, propionic, butyric and isobutyric acids. The corresponding acetate, propionate and butyrate esters of 3,7-dimethyl-2-tridecanol were also found in the samples. All esters were electrophysiologically active, and the propionate and isobutyrate were attractive in trapping experiments. Based on these and earlier reported results, it seems that at least in part of its range, the pheromone response of D. pini is not very specific with regard to the functional group, as long as this is an ester.

     

     

  • 10.
    Andersson, Fredrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Highly stereoselective alkylation of (S)-proline-based chiral auxiliaries2004In: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 15, no 16, p. 2539-2545Article in journal (Refereed)
    Abstract [en]

    Alkylation of the enolates of the propanoylamides of two chiral auxiliaries (S)-(-)-2-(pyrrolidin-2-yl)propan-2-ol 1a and (S)-(-)-2-(2-methoxypropan-2-yl)pyrrolidine 1b, derived from (S)-proline, with benzyl bromide and n-butyl iodide has been studied. The auxiliaries 1a and 1b induced opposite selectivity that is (R)- and (S)-configuration, respectively, at the newly created stereogenic centre. The diastereoselectivities and conversion yields in these alkylations were moderate to excellent. When Cp2ZrCl2 was used as an enolate coordinating agent, benzylation of propanoylated 1b gave an excellent diastereomeric ratio of 99:1. The benzylated diastereomeric products from either propanoylated 1a or 1b were easily separated by liquid chromatography.

  • 11.
    Andersson, Fredrik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Synthesis of two (S)-indoline-based chiral auxiliaries and their use in diastereoselective alkylation reactions2006In: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 17, no 13, p. 1952-1957Article in journal (Refereed)
    Abstract [en]

    Two chiral auxiliaries, 2-[(S)-indolin-2-yl]propan-2-ol 1a and (S)-2-(2-methoxypropan-2-yl)indoline 1b, were synthesised from enantiomerically pure (S)-indoline-2-carboxylic acid 3. High diastereoselectivities in alkylations of enolates of the propanoylamides derived from the two auxiliaries are presented. Surprisingly, both auxiliaries induced the same selectivity at the newly created stereogenic centre. The benzyl bromide and n-butyl iodide alkylation reactions showed diastereomeric ratios that were moderate (81:19) to very good (96:4) and with very good yields (86-98%). When LiCl was used as an enolate coordinating agent, in the benzylation of the enolate from propanoylated auxiliary 1a, a very high crude diastereomeric ratio was obtained (99.7:0.3).

  • 12.
    Andersson, K.
    et al.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, SE-23053 Alnarp, Sweden.
    Bergman, K. -O
    IFM Biology, Conservation Ecology Group, Linköping University, SE-58183 Linköping, Sweden.
    Andersson, Fredrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Jansson, N.
    IFM Biology, Conservation Ecology Group, Linköping University, SE-58183 Linköping, Sweden.
    Burman, J.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, SE-23053 Alnarp, Sweden.
    Winde, I.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, SE-23053 Alnarp, Sweden.
    Larsson, M. C.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, SE-23053 Alnarp, Sweden.
    Milberg, P.
    IFM Biology, Conservation Ecology Group, Linköping University, SE-58183 Linköping, Sweden.
    High-accuracy sampling of saproxylic diversity indicators at regional scales with pheromones: The case of Elater ferrugineus (Coleoptera, Elateridae)2014In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 171, p. 156-166Article in journal (Refereed)
    Abstract [en]

    The rare beetle Elater ferrugineus was sampled at 47 sites in the county of Östergötland, Sweden by means of pheromone-baited traps to assess its value as an indicator species for hollow oak stands rich in rare saproxylic beetle species. In addition, Osmoderma eremita was also sampled with pheromone baits. These data were then compared against species survey data collected at the same sites by pitfall and window traps. Both species co-occur with many Red Listed saproxylic beetles, with E. ferrugineus being a somewhat better indicator for the rarest species. The conservation value of a site (measured as Red List points or number of Red Listed species) increased with the number of specimens of E. ferrugineus and O. eremita caught. Accuracy of sampling by means of pheromone trapping turned out to be radically different for the two model species. E. ferrugineus traps put out during July obtained full accuracy after only 6. days, whereas O. eremita traps needed to be out from early July to mid-August in order to obtain full accuracy with one trap per site. By using E. ferrugineus, or preferably both species, as indicator species, accuracy would increase and costs decrease for saproxylic biodiversity sampling, monitoring and identification of hotspots. © 2014 Elsevier Ltd.

  • 13.
    Becher, Paul G.
    et al.
    Swedish University of Agricultural Sciences, Alnarp.
    Lebreton, Sebastien
    Swedish University of Agricultural Sciences, Alnarp.
    Wallin, Erika
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Borrero, Felipe
    Colombian Corporation of Agricultural Research, Las Palmas, Bogota, Colombia.
    Bengtsson, Marie
    Swedish University of Agricultural Sciences, Alnarp.
    Joerger, Volker
    Staatliches Weinbauinstitut, Freiburg, Germany.
    Witzgall, Peter
    Swedish University of Agricultural Sciences, Alnarp.
    The Scent of the Fly2018In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 44, no 5, p. 431-435Article in journal (Refereed)
    Abstract [en]

    (Z)-4-undecenal (Z4-11Al) is the volatile pheromone produced by females of the vinegar fly Drosophila melanogaster. Female flies emit Z4-11Al for species-specific communication and mate-finding. A sensory panel finds that synthetic Z4-11Al has a characteristic flavour, which can be perceived even at the small amounts produced by a single female fly. Since only females produce Z4-11Al, and not males, we can reliably distinguish between single D. melanogaster males and females, according to their scent. Females release Z4-11Al at 2.4 ng/h and we readily sense 1 ng synthetic Z4-11Al in a glass of wine (0.03 nmol/L), while a tenfold concentration is perceived as a loud off-flavour. This corroborates the observation that a glass of wine is spoilt by a single D. melanogaster fly falling into it, which we here show is caused by Z4-11Al. The biological role of Z4-11Al or structurally related aldehydes in humans and the basis for this semiochemical convergence remains yet unclear. 

  • 14. Berglund, P.
    et al.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hult, K.
    Controlling lipase enantioselectivity for organic synthesis: Meeting abstract2000In: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 2000, Vol. 219, p. U219-Conference paper (Refereed)
  • 15.
    Berglund, Per
    et al.
    Department of Biotechnology, Royal Institute of Technology, SE-100 44 Stockholm.
    Christiernin, M
    Department of Biotechnology, Royal Institute of Technology, SE-100 44 Stockholm.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Enantiorecognition of Chiral Acids by Candida rugosa Lipase: Two Substrate Binding Modes Evidenced in an Organic Medium2001In: Applied Biocatalysis in Speciality Chemicals and Pharmaceuticals, 2001, p. 263-273Conference paper (Refereed)
    Abstract [en]

    We have identified the existence of different modes of binding the enantiomers of 2-methyl-branched carboxylic acids to a lipase active site by rational substrate engineering. Similar to hydrolysis, previously investigated, we have now evidence for differential binding modes in the Candida rugosa lipase-catalyzed esterifications in cyclohexane. The relevance of considering two different binding modes to understand lipase enantiorecognition is demonstrated by introducing bulky substituents on a chiral carboxylic acid which impose a different orientation of the substrate acyl chain in the active site of Candida rugosa lipase. With this substrate engineering approach based on molecular modeling it is thus possible to markedly alter the enantioselectivity of the lipase. Examples from hydrolysis and new results from esterifications in an organic solvent are presented and discussed.

  • 16. Berglund, Per
    et al.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Preparation of 2-, 3-, and 4-methylcarboxylic acids and the corresponding alcohols of high enantiopurity by lipase catalyzed esterification2001In: Enzymes in Nonaqueous Solvents: Methods and Protocols, Humana Press, 2001, p. 307-317Chapter in book (Other academic)
  • 17.
    Berglund, Per
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Holmquist, M
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hult, K
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    2-Methylalkanoic Acids Resolved by Esterification Catalysed by Candida rugosa: Alcohol Chain Length and Enantioselectivity1993In: Tetrahedron: Asymmetry, ISSN 0957-4166, Vol. 4, no 8, p. 1869-1878Article in journal (Refereed)
  • 18. Bergström, G
    et al.
    Wassgren, A.-B.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hefetz, Abraham
    Simon, Dan
    Ohlsson, T
    Löfqvist, J
    Species specific, Two-Component, Volatile Signals in two Sympatric Ant-lion Species: Synclysis baetica and Acanthaclisis occitanica (Neuroptera, Myrmeleontidae1992In: Journal of Chemical Ecology, ISSN 0098-0331, Vol. 17, no 7, p. 1177-1188Article in journal (Refereed)
  • 19. Bergström, Gunnar
    et al.
    Wassgren, A.-B.
    Anderbrant, O
    Fägerhag, Jonas
    Edlund, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Geri, C
    Auger, M. A.
    Varama, M
    Hansson, B. S.
    Löfqvist, J
    Sex pheromone of the pine sawfly Diprion pini (Hymenoptera: Diprionidae): Chemical identification, synthesis and biological activity1995In: Experientia, ISSN 0014-4754, Vol. 51, no 4, p. 370-380Article in journal (Refereed)
  • 20. Bergström, Gunnar
    et al.
    Wassgren, Ann-Britt
    Anderbrant, Olle
    Ochieng, Samuel
    Östrand, Fredrik
    Hansson, Bill S.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Sex Pheromone of the Pine Sawfly Microdiprion pallipes (Hymenoptera: Diprionidae)1998In: Naturwissenschaften, ISSN 0028-1042, Vol. 85, no 5, p. 244-248Article in journal (Refereed)
  • 21.
    Boija, Susanne
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Almesåker, Ann
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Bylund, Dan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Edlund, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Norgren, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Determination of conditional stability constants for some divalent transition metal ion-EDTA complexes by electrospray ionization mass spectrometry2014In: Journal of Mass Spectrometry, ISSN 1076-5174, E-ISSN 1096-9888, Vol. 49, no 7, p. 550-556Article in journal (Refereed)
    Abstract [en]

    Conditional stability constants of coordination complexes comprising divalent transition metals, Cu2+, Ni2+, Zn2+, Co2+, and ethylenediaminetetraacetic acid (EDTA) were determined utilizing electrospray ionization mass spectrometry. The deviation of signal response of a reference complex was monitored at addition of a second metal ion. The conditional stability constant for the competing metal was then determined through solution equilibria equations. The method showed to be applicable to a system where Co2+ and Zn2+ competed for EDTA at pH 5. When Cu2+ and Ni2+ competed for EDTA, the equilibrium changed over time. This change was shown to be affected in rate and size by the type of organic solvent added. In this work, 30% of either methanol or acetonitrile was used. It was found that if calibration curves are prepared for both metal complexes in solution and the measurements are repeated with sufficient time space, any change in equilibrium of sample solutions will be discovered. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  • 22.
    Breistein, Palle
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Karlsson, Staffan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Chiral pyrrolidinium salts as organocatalysts in stereoselective 1,4-conjugate addition of N-methylpyrrole to cyclopent-1-ene carbaldehyde2006In: Tetrahedron: Asymmetry, ISSN 0957-4166, Vol. 17, no 1, p. 107-111Article in journal (Refereed)
  • 23.
    Bydén Sjöbom, Malin
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Edlund, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Binary Phase Equilibria of Three alfa-Methylsubstituted Sodium Alkanoate Surfactant Systems.2003In: Journal of Colloid and Interface Science, ISSN 0021-9797, Vol. 257, no 2, p. 333-336Article in journal (Refereed)
    Abstract [en]

    In this work, we continue our study of methyl -substituted surfactants and present the aqueous binary phase diagrams of racemic sodium 2-methyloctanoate, -nonanoate, and -dodecanoate, respectively. All systems have very low Krafft temperatures within the solution phase, between 1 and 4 degreesC. The phase sequences of the two shorter surfactants are very similar to those of the unsubstituted sodium octanoate, although with somewhat different range of existence for the phases formed. The sodium 2-methyldodecanoate system is different from the unsubstituted sodium dodecanoate system, as the former seems to lack a hexagonal phase. The surfactant systems were delineated using H-2 NMR splittings and crossed polarizers, and combined with SAXS for determination of phase structure. 

  • 24.
    Bång, Joakim
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Anderbrant, Olle
    Lund Univ, Dept Biol, Lund, Sweden.
    Stereoisomeric separation of derivatized 2-alkanols using gas chromatography – mass spectrometry: Sex pheromone precursors found in pine sawfly species2012In: Analytical Letters, ISSN 0003-2719, E-ISSN 1532-236X, Vol. 45, no 9, p. 1016-1027Article in journal (Refereed)
    Abstract [en]

    Stereoisomers of long-chain secondary alcohols are used as sex pheromone precursors among pine sawflies, which can be severe pest to conifers. To use the pheromone in environmentally friendly pest managements, methods are needed that can determine the exact stereochemistry of the precursor alcohols. Combinations of 11 acid chloride derivatives and 10 GC columns were evaluated for separation of the stereoisomers of 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, 3,7-dimethyltridecan-2-ol, 3,7-dimethyltetradecan-2-ol, and 3,7-dimethylpentadecan-2-ol. Derivatisation with (2S)-2-acetoxypropionyl chloride in combination with the Chiraldex B-PA column separated all eight stereoisomers of 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol and 3,7-dimethyltridecan-2-ol. A combination of two different derivatisation methods was needed to separate all stereoisomers of the longer chained alcohols, 3,7-dimethyltetradecan-2-ol and 3,7-dimethylpentadecan-2-ol. An extract of the pine sawfly Neodiprion lecontei was also analysed, and the stereochemistry of the sex pheromone alcohol prcursor was determined to be (2S,3S,7S)-3,7-dimethylpentadecan-2-ol, at an amount of about 7 ng/female. This paper presents the first GC-MS-separation of all eight stereoisomers of 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol and 3,7-dimethyltridecan-2-ol in a single analytical run, and also the first determination of the stereochemistry of the sex pheromone precursor of N. lecontei.

  • 25.
    Bång, Joakim
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Sjödin, Kristina
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Purification, Stereoisomeric Analysis and Quantification of Sex Pheromone Precursors in Female Whole Body Extracts from Pine Sawfly Species2011In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 37, no 1, p. 125-133Article in journal (Refereed)
    Abstract [en]

    A GC-MS method to analyze the stereoisomeric composition of chiral secondary alcohols found in whole body extracts of pine sawfly females was developed. The tested alcohols were derivatized with optically pure (S)-2-acetoxypropionyl chloride prior to GC-MS analysis. Baseline separation was obtained for all sixteen stereoisomers of 3,7,9-trimethyltridecan-2-ol and for the four 3-methylpentadecan-2-ol stereoisomers. For 3,7-dimethyltridecan-2-ol, 3,7-dimethyltetradecan-2-ol and 3,7-dimethylpentadecan-2-ol baseline separation was obtained for 6 of the possible 8 stereoisomers. When a mixture of 16 stereoisomers of 3,7,11-trimethyltridecan-2-ol was tested, baseline separation of 7 peaks out of 16 possible was obtained. The investigated alcohols are pheromone precursors for some pine sawfly species that are severe defoliators of pine. Females from several Diprion, Neodiprion, Macrodiprion, Microdiprion, and Gilpinia species emit esters of such secondary alcohols as sex pheromones that attract males for mating. To quantify the small amounts of the precursor alcohol and its stereoisomeric composition found in whole body extracts from female pine sawflies, a purification method was optimized. An extract of 20 females of D. pini contained about 8 ng of (2 S,3 R,7 R)-3,7-dimethyltridecan-2-ol per female, and three extracts of 18, 20, and 90 females of N. sertifer contained between 5 and 13 ng of (2 S,3 S,7 S)-3,7-dimethylpentadecan-2-ol per female.

  • 26.
    Duan, Ran
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Norgren, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Edlund, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Novel foamed materials from renewable sources2012In: 9th European Conference on Foams, Emulsions and Applications, 2012Conference paper (Refereed)
  • 27.
    Duan, Ran
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Norgren, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Ibrahem, Ismail
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Edlund, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    New approaches toward producing foamed materials from renewable sources.2013Conference paper (Refereed)
  • 28.
    Edlund, Håkan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Berglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Jensen, M
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Resolution of 2-Methylalkanoic Acids: Enantioselective Esterification with Long Chain Alcohols Catalysed by Candida rugosa Lipase1996In: Acta Chemica Scandinavica, ISSN 0904-213X, Vol. 50, no 8, p. 666-671Article in journal (Refereed)
  • 29. Eltz, Thomas
    et al.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Bång, Joakim
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Wallin, Erika A
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Andersson, Jimmy
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    (6R,10R)-6,10,14-Trimethylpentadecan-2-one, a Dominant and Behaviorally Active Component in Male Orchid Bee Fragrances2010In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 36, no 12, p. 1322-1326Article in journal (Refereed)
    Abstract [en]

    6,10,14-Trimethylpentadecan-2-one (Hexahydrofarnesyl acetone; HHA) previously has been found to be a major component in tibial fragrances of male orchid bees, Euglossa spp. HHA is a chiral molecule with four possible stereoisomers, (6R,10R)-, (6R,10S)-, (6S,10R)-, and (6S,10S)-6,10,14-trimethylpentadecan-2-one. In the present study, we characterized HHA extracted from Euglossa as the pure enantiomer (6R,10R)-6,10,14-trimethylpentadecan-2-one. During bioassays in Mexico and Panama, the synthetic RR-isomer attracted males of six species of orchid bees, including three that were known to contain HHA in their tibial fragrances. Possible sources of HHA for wild bees are flowers of euglossophilous orchids and aroids. With a molecular weight of 268, HHA is the largest natural molecule known to attract male orchid bees in pure form. Its attractiveness to males suggests that low-volatility compounds have a function in male signals, e.g., serve as a "base note" in complex odor bouquets. © 2010 Springer Science+Business Media, LLC.

  • 30.
    Fagerlund-Edfeldt, Amelie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Edman, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Jonsson, Bengt Gunnar
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Effect of Debarking Water from Norway Spruce (Picea abies) on the Growth of Five Species of Wood-Decaying Fungi2014In: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 9-10, no 69c, p. 418-424Article in journal (Refereed)
    Abstract [en]

    Norway spruce (Picea abies) debarking water is an aqueous extract obtained as waste from the debarking of logs at paper mills. The debarking water contains a mixture of natural compounds that can exhibit diverse biological activities, potentially including fungicidal activity on some species of wood-decaying fungi. Thus, we investigated the growth rates of such fungi on agar plates to which debarking water extracts had been added. The experiment included five wood-decaying fungi, viz. Gloeophyllum sepiarium, Oligoporus lateritius, Ischnoderma benzoinum, Junghuhnia luteoalba, and Phlebia sp. Growth reduction was observed for all species at the highest tested concentrations of freeze-dried and ethanol-extracted debarking water, the ethyl acetate-soluble fraction and the diethyl ether-soluble fraction. However, the magnitude of the effect varied between different species and strains of individual species. The brown-rot fungi G. sepiarium and O. lateritius were generally the most sensitive species, with the growth of all tested strains being completely inhibited by the ethyl acetate-soluble fraction. These results indicate that development of antifungal wood-protecting agents from debarking water could potentially be a way to make use of a low-value industrial waste.

  • 31.
    Hagström, Å.K.
    et al.
    Pheromone group, Department of Biology, Lund University, Lund, Sweden.
    Liénard, M
    Pheromone group, Department of Biology, Lund University, Lund, Sweden.
    Groot, A
    Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Löfstedt, C
    Pheromone group, Department of Biology, Lund University, Lund, Sweden.
    Semi-selective fatty acyl reductases from four heliothine moths influence the specific pheromone composition2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 5, p. Art. no. e37230-Article in journal (Refereed)
    Abstract [en]

    Background: Sex pheromones are essential in moth mate communication. Information on pheromone biosynthetic genes and enzymes is needed to comprehend the mechanisms that contribute to specificity of pheromone signals. Most heliothine moths use sex pheromones with (Z)-11-hexadecenal as the major component in combination with minor fatty aldehydes and alcohols. In this study we focus on four closely related species, Heliothis virescens, Heliothis subflexa, Helicoverpa armigera and Helicoverpa assulta, which use (Z)-11-hexadecenal, (Z)-9-tetradecanal, and (Z)-9-hexadecenal in different ratios in their pheromone blend. The components are produced from saturated fatty acid precursors by desaturation, β-oxidation, reduction and oxidation. Results: We analyzed the composition of fatty acyl pheromone precursors and correlated it to the pheromone composition. Next, we investigated whether the downstream fatty-acyl reduction step modulates the ratio of alcohol intermediates before the final oxidation step. By isolating and functionally characterizing the Fatty Acyl Reductase (pgFAR) from each species we found that the pgFARs were active on a broad set of C8 to C16 fatty acyl substrates including the key pheromone precursors, Z9-14, Z9-16 and Z11-16:acyls. When presenting the three precursors in equal ratios to yeast cultures expressing any of the four pgFARs, all reduced (Z)-9-tetradecenoate preferentially over (Z)-11-hexadecenoate, and the latter over (Z)-9-hexadecenoate. Finally, when manipulating the precursor ratios in vitro, we found that the pgFARs display small differences in the biochemical activity on various substrates. Conclusions: We conclude that a pgFAR with broad specificity is involved in heliothine moth pheromone biosynthesis, functioning as a semi-selective funnel that produces species-specific alcohol product ratios depending on the fatty-acyl precursor ratio in the pheromone gland. This study further supports the key role of these in pheromone biosynthesis and emphasizes the interplay between the pheromone fatty acyl precursors and the Lepidoptera specific pgFARs in shaping the pheromone composition. © 2012 Hagström et al.

  • 32. Hansson, B. S.
    et al.
    van der Pers, J. N. C.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Sex Pheromone Perception in male pine sawflies, Neodiprion sertifer (Hymenoptera; Diprionidae)1991In: Journal of Comparative Physiology A, ISSN 0340-7594, Vol. 168, no 5, p. 533-538Article in journal (Refereed)
  • 33.
    Harvey, Deborah J.
    et al.
    Royal Holloway University of London, UK.
    Harvey, Hannah
    Royal Holloway University of London, UK.
    Harvey, Rachael P.
    UCL, London, England.
    Kadej, Marcin
    Univ Wroclaw, Poland.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Gange, Alan C.
    Royal Holloway University of London, UK.
    Finch, Paul
    Royal Holloway University of London, UK.
    Use of novel attraction compounds increases monitoring success of a rare beetle, Elater ferrugineus2017In: Insect Conservation and Diversity, ISSN 1752-458X, E-ISSN 1752-4598, Vol. 10, no 2, p. 161-170Article in journal (Refereed)
    Abstract [en]

    The use of pheromones to determine distributions of rare saproxylic insects is an increasingly popular technique. Pheromones may, however, also be used to elucidate the biology of these cryptic species, a vital requirement if they are to be accurately monitored and conserved. We used non-invasive aerial trapping to compare the effectiveness of chemicals produced by Elater ferrugineus L (Coleoptera: Elateridae), namely 7-methyloctyl (Z)-4-decenoate (the female-produced sex pheromone), and male compounds (geranyl and neryl acetone and 6-methyl-5-heptene-2-one). The male compounds were identified using headspace analysis by solid phase micro-extraction gas chromatography-mass spectrometry. We discovered that males only produce these two compounds after having been attracted to a female, and that this serves to attract further males to a female. Such compounds do not appear to attract females but for a species that has a short activity period and is non-feeding in the adult stage, may ensure breeding success when populations are low. By marking all beetles caught, we were able to demonstrate that recapture rate using this method is low (approximately 11% of total captures annually). Therefore, the method does not limit dispersal or breeding opportunities, making it a valuable tool for monitoring endangered saproxylic beetle species.

  • 34.
    Harvey, Deborah J.
    et al.
    School of Biological Sciences, Royal Holloway University of London, Egham, UK.
    Harvey, Hannah
    School of Biological Sciences, Royal Holloway University of London, Egham, UK.
    Larsson, Mattias C.
    Swedish University of Agricultural Sciences, Alnarp.
    Svensson, Glenn P.
    Lund University, Lund.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Finch, Paul
    School of Biological Sciences, Royal Holloway University of London, Egham, UK.
    Gange, Alan C.
    School of Biological Sciences, Royal Holloway University of London, Egham, UK.
    Making the invisible visible: Determining an accurate national distribution of Elater ferrugineus in the United Kingdom using pheromones2017In: Insect Conservation and Diversity, ISSN 1752-458X, E-ISSN 1752-4598, Vol. 10, no 4, p. 1-11Article in journal (Refereed)
    Abstract [en]

    To date, conservation-status saproxylic beetle species in the UK have been monitored by chance findings or by monitor-based observational studies. Here, using Elater ferrugineus as our target species, we present the first national distribution survey carried out in the UK or across mainland Europe on such a species using chemicals produced by the insect. Over 3 years, mark-release-recapture studies were performed across the UK, using 416 lured (pheromone) traps monitored by volunteer recorders; the first survey in Europe to do so. Traps were baited with 7-methyloctyl- (Z)-4-decenoate, a compound previously identified as a female sex pheromone. The results were used to plot a distribution map and investigate factors that may influence the distribution, including summer temperatures, possible habitat availability and larval food source. The survey revealed a south-eastern distribution of E. ferrugineus in the UK, which was suggested by previous casual studies. A correlative model was fitted to the data, indicating that 55% of the variation in the distribution of E. ferrugineus was explained by climatic variables (temperature and wind speed).

  • 35.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Andersson, Fredrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Syntheses of female sex pheromone precursors of pine sawflies species and of some structurally related methyl-branched long-chain 2-alkanols2002In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 28, no 6, p. 1237-1254Article in journal (Refereed)
    Abstract [en]

    3,7-Dimethyl-2-undecanol, 3,7,9-trimethyl-2-tridecanol, and 3,7, 11-trimethyl-2-tridecanol were synthesized as racemic mixtures in moderate yields. The alcohols are known precursors of the female sex pheromones of the pine sawfly species Diprion nipponica, Macrodiprion nemoralis, and Microdiprion pallipes, respectively. Stereoisomeric mixtures of 3,8,12-trimethyl-2-tridecanol, erythro-(2R,3R,11R/S)-3,11-dimethyl-2-tetradecanol, 3,5-dimethyl-2-tetradecanol, and 5,7-dimethyl-2-tetradecanol, structurally related to sex pheromone alcohol precursors of pine sawfly species, were also synthesized in moderate yields. The key reaction in the syntheses was the ring opening of γ-butyrolactones by using different alkyl lithiums as nucleophiles.

  • 36.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Andersson, Fredrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hjalmarsson, Mats
    Synthesis of N-propionylated (S)-(-)-2-(pyrrolidin-2-yl)propan-2-ol and its use as a chiral auxiliary and selectivity marker in asymmetric aldol reactions2000In: Journal of the Chemical Society. Perkin Transactions 1, ISSN 1472-7781, Vol. 2000, p. 1513-1518Article in journal (Refereed)
    Abstract [en]

    The N-propionylated pyrrolidine derivative and chiral auxiliary, (S)-(-)-2-(pyrrolidin-2-yl)propan-2-ol, was synthesised and used in stereoselective aldol reactions with benzaldehyde. Differences in stereoselectivity were investigated as a function of temperature, solvent, chelating agent and the amount of the chelating agent used by monitoring the 1H NMR spectra of the aldol adducts that were obtained. Among the additives that were investigated, Cp2ZrCl2 induced higher syn-selectivity, while SnCl2 induced higher syn-selectivity respectively. TMSCl was found to induce high selectivity for one syn- and one anti-diastereomer. Varying the ligand sets on titanium additives was found to induce differences in selectivity, with (i-PrO)3TiCl exhibiting syn-selectivity and Cp2TiCl2 exhibiting anti-selectivity. Differences in reactivity and stereoselectivity were also found to depend upon the amount of Lewis acid that was added. Methods for removal of the auxiliary were also investigated. Acidic hydrolysis was used successfully to obtain the desired 3-hydroxy-2-methyl-3-phenylpropionic acids, but was found to give low yields and resulted in a large amount of epimerisation. Furthermore, the ethyl esters of these hydroxy acids are easy to separate into pure syn- and anti-diastereomers by LC. © The Royal Society of Chemistry 2000.

  • 37.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Andersson, Fredrik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Sjöberg, Natalia
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Eltz, Thomas
    Ruhr University Bochum, Bochum, Germany.
    6-(4-Methylpent-3-en-1-yl)naphthalene-1,4-dione, a behaviorally active semivolatile in tibial perfumes of orchid bees2018In: Chemoecology, ISSN 0937-7409, E-ISSN 1423-0445, Vol. 28, no 4-5, p. 131-135Article in journal (Refereed)
    Abstract [en]

    Male neotropical orchid bees (Euglossini) collect volatiles from varied sources in their environment to compile complex, species-specific tibial perfumes, which are later released at mating sites. A major compound prominent in tibial extracts of Euglossa allosticta was purified, as well as isolated and its structure was elucidated by analytical methods including GC–MS, GC–FTIR, HRMS and 1H and 13C NMR. After synthesis, the compound with the proposed structure was finally identified as 6-(4-methylpent-3-en-1-yl)naphthalene-1,4-dione. At field sites in Panama and Costa Rica, the synthetic compound attracted males of E. allosticta, but no other euglossines. This strengthens the view that semivolatiles play an important role in conveying specificity to perfume signals of orchid bees. 

  • 38.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Edlund, Helen
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Lund, Susan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Stereoselective esterification of 2,6-dimethyl-1,7-heptanedioic acid, catalysed by Candida rugosa lipase2003In: Journal of Molecular Catalysis B: Enzymatic, ISSN 1381-1177, E-ISSN 1873-3158, Vol. 23, no 1, p. 53-59Article in journal (Refereed)
    Abstract [en]

    The immobilised Candida rugosa lipase (CRL) displayed S-preference for both stereogenic centres in this sequential esterification of 2,6-dimethyl-1,7-heptanedioic acid (1) (pure meso and meso: (+/-) mixture, 53/47) with n-butanol in cyclohexane at a(w) = 0.8. The reaction was faster when short-chain primary n-alcohols was used and very slow, or even none reactive, when a Ion-chain alcohol was used.

  • 39.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Edlund, Helen
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Lund, Susan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Abersten, M.
    Persson, D.
    Synthesis and lipase catalysed stereoselective acylation of some 3-methyl-2-alkanols, identified as sex pheromone precursors in females of pine sawfly species2002In: Journal of The Chemical Society, Perkin Transactions 1, ISSN 1472-7781, Vol. 2002, no 15, p. 1810-1817Article in journal (Refereed)
    Abstract [en]

    Several 3-methylalkan-2-ols precursors to sex pheromones of Diprion pini, Gilpinia pallida, Gilpinia frutetorum, Diprion nipponica, Macrodiprion nemoralis and Microdiprion pallipes were synthesised as stereoisomeric mixtures in moderate to good yields. The key reaction sequence in the syntheses was the ring opening of either cis- or racemic trans-epoxybutane using a higher order cyanocuprate as nucleophile followed by a highly efficient lipase catalysed stereoselective acylation of the obtained 3-methylalkan-2-ol. The biologically active species specific stereoisomer was synthesised as a single stereoisomer in high stereoisomeric purity, as one in a mixture of two or as one of four stereoisomers when the appropriate 3-methylalkan-2-ol was stereoselectively acylated using a Pseudomonas sp. lipase as catalyst.

  • 40.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Edlund, Helene
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Wassgren, Ann-Britt
    Bergström, Gunnar
    Anderbrant, Olle
    Östrand, Fredrik
    Sierpinski, Andrzej
    Auger-Rozenberg, Marie-Anne
    Herz, Annette
    Heitland, Werner
    Varama, Martti
    The Sex Pheromones of Two Pine Sawfly Species, Gilpinia frutetorum and Gilpinia socia: Chemical Identification, Synthesis and Biological Activity2009In: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 64, no 9-10, p. 733-742Article in journal (Refereed)
    Abstract [en]

    3,7-Dimethylpentadecan-2-ol and 3-methylpentadecan-2-ol were identified in female whole body extracts from the two pine sawfly species Gilpinia frutetorum and Gilpinia socia. This is the first observation of 3-methylpentadecan-2-ol in extracts of a female pine sawfly species. Synthetic and highly pure stereoisomers of 3,7-dimethylpentadecan-2-ol and 3-methylpentadecan-2-ol were used to verify that the (2S,3R,7R)-isomer of 3,7-dimethyl- pentadecan-2-ol and (2S,3R)-3-methylpentadecan-2-ol were present in the extracts. The four stereoisomers of 3-methylpentadecan-2-ol and their biologically active esters were produced via chemoenzymatic methods and the synthesis is described in detail. Male G. socia anten- nae responded strongly in EAG recordings to the (2S,3R)-isomer of the acetate and propionate of 3-methylpentadecan-2-ol. Male antennae of both G. frutetorum and G. socia also responded to the (2S,3R,7R)- and (2S,3R,7S)-acetates of 3,7-dimethylpentadecan-2-ol.

  • 41.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Edlund, Helene
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Wassgren, Ann-Britt
    Göteborg University.
    Bergström, Gunnar
    Göteborg University.
    Anderbrant, Olle
    Lund University.
    Östrand, Fredrik
    Lund University.
    Sierpinski, Andrzej
    Forest Research Institute, Poland.
    Auger-Rozenberg, Marie-Anne
    Institut National de la Recherche Agronomique, France.
    Herz, Marie-Anne
    Technische Universität München, Germany.
    Heitland, Werner
    Technische Universität München, Germany.
    Varama, Martti
    Finnish Forest Research Institute, Finland.
    Sex pheromone of the pine sawfly, Gilpinia pallida: Chemical identification, synthesis, and biological activity2006In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 32, no 11, p. 2525-2541Article in journal (Refereed)
    Abstract [en]

    We present the identification of the sex pheromone in the pine sawfly, Gilpinia pallida, including analysis of the female pheromone content, male antennal response and attraction in the field, and synthesis of the most active pheromone component. Several 3,7-dimethyl-2-alkanols were identified from female whole-body extracts, including some compounds with a 2R configuration. This is the first observation of such compounds in a pine sawfly species. Antennae of male G. pallida responded strongly in electroantennograph (EAG) recordings to the (2S,3R,7R)-isomers of the propionates of 3,7-dimethyl-2-tridecanol, 3,7-dimethyl-2-tetradecanol, and 3,7-dimethyl-2-pentadecanol, as well as to the acetates of the tri- and pentadecanols (the acetate of the tetradecanol was not tested). The propionate of (2S,3R,7R)-3,7-dimethyl-2-tetradecanol caught more males in the field than the corresponding isomer of tri- or pentadecanol. We suggest that the (2S,3R,7R)-isomer of 3,7-dimethyl-2-tetradecanol is likely the main sex pheromone precursor in G. pallida, with a subsidiary role for the (2S,3R,7R)-isomer of the tridecanol. Preparation of highly pure (2R,3R,7R)- and (2S,3R,7R)-stereoisomers of 3,7-dimethyl-2-tetradecanol, including the biological active esters, was performed via chemoenzymatic methods and is described in detail.

  • 42.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Fagerlund-Edfeldt, Amelie
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Edman, Mattias
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Jonsson, Bengt-Gunnar
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Resveratrol, piceatannol, and isorhapontigenin from Norway spruce (Picea abies) debarking wastewater as inhibitors on the growth of nine species of wood-decaying fungi2016In: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 50, no 3, p. 617-629Article in journal (Refereed)
    Abstract [en]

    The diethyl ether extract obtained from solvent-solvent extraction of Norway spruce (Picea abies) debarking water, a byproduct from debarking of logs in the pulp and paper industry, was tested for inhibition of growth on agar plates of nine species of wood-decaying fungi: Antrodia sinuosa, Antrodia xantha, Coniophora puteana, Fomitopsis pinicola, Gloeophyllum sepiarium, Heterobasidion parviporum, Phlebiopsis gigantea, Serpula himantioides, and Serpula lacrymans. One fraction of the extract showed excellent antifungal activity for a majority of the species, with complete inhibition of growth for A. sinuosa, A. xantha, and G. sepiarium. The major constituents of the most active fraction were identified as the hydroxystilbenes resveratrol, isorhapontigenin (synonymous with methyl piceatannol), and piceatannol (synonymous with astringenin). The active compounds were isolated or synthesized and used individually for dose-response studies. It was found that isorhapontigenin and piceatannol inhibited all growth of A. sinuosa, A. xantha, and G. sepiarium in 0.35 % weight concentration. The hydroxystilbenes were the three most abundant substances in the debarking water and can be obtained as a mixture or in enriched forms. From some extraction steps of the raw debarking water, it would be possible to obtain the hydroxystilbenes in quantities that might be of commercial interest as efficient natural fungicides.

  • 43.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Efficient Opening of trans-2,3-Epoxybutane by a Higher Order Cuprate: Synthesis of erythro-3.7-Dimethylpentadecan-2-yl Acetate, Pheromone of Pine Sawflies1994In: Tetrahedron, ISSN 0040-4020, Vol. 50, no 17, p. 5225-5232Article in journal (Refereed)
  • 44.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Anderbrant, Olle
    Wang, H.B.
    Zhang, Z.
    Chen, G.F.
    Sex pheromone for monitoring flight periods and population densities of the pine sawfly, Diprion jingyuanensis Xiao et Zhang (Hym.: Diprionidae)2010In: Forests for the Future - Sustaining Society and the Environment: Abstracts / [ed] John A Parrotta and Mary A Carr, 2010, Vol. 12, no 5, p. 369-369Conference paper (Refereed)
  • 45.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Wassgren, A.-B.
    Bergström, G.
    Löfqvist, J.
    Hansson, B.
    Anderbrant, O.
    Sex Pheromone of Pine Sawflies: Chiral Syntheses of some Active Minor Components Isolated from Neodiprion sertifer and of some Chiral Anologues of Diprionyl Acetate1992In: Tetrahedron, ISSN 0040-4020, Vol. 48, no 15, p. 3139-3146Article in journal (Refereed)
  • 46.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Nguyen, Ba-Vu
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Silks III, L. A.
    Do enzymes recognise remotely located stereocentres?: Highly enantioselective Candida rugosa lipase-catalysed esterification of the 2- to 8-methyldecanoic acids2002In: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 13, no 8, p. 835-844Article in journal (Refereed)
    Abstract [en]

    Several racemic methyl decanoic acids have been synthesised and successfully resolved in esterification with 1-hexadecanol at aw=0.8 in cyclohexane using immobilised Candida rugosa lipase (CRL) as the catalyst. The enantiomeric ratios (E=2.8-68) obtained were surprisingly high even when the methyl group was as remotely located as in 8-methyldecanoic acid (E=25). Interestingly, the lipase shows enantiopreference for the S-enantiomer when the methyl group is located on even numbered carbons i.e. for the 2-,4-,6- and 8-methyldecanoic acids and to the R-enantiomer when the methyl group is located on uneven numbered carbons i.e. for the 3-,5- and 7-methyldecanoic acids.

  • 47.
    Hedenström, Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Wallin, Erika
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Andersson, J
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Bång, Joakim
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Wang, H-L
    Department of Biology, Lund University, Sölvegatan 37, Lund, Sweden .
    Löfstedt, C
    Department of Biology, Lund University, Sölvegatan 37, Lund, Sweden .
    Brattström, O
    Department of Zoology, Cambridge University, Cambridge, United Kingdom.
    Baquet, P
    Evolutionary Ecology and Genetics group, Biodiversity Research Centre, Earth and Life Institute, Académie Louvain, Croix du Sud 4, Louvain-la-Neuve, Belgium.
    Stereoisomeric Analysis of 6,10,14-Trimethylpentadecan-2-ol and the Corresponding Ketone in Wing Extracts from African Bicyclus Butterfly Species2015In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 41, no 1, p. 44-51Article in journal (Refereed)
    Abstract [en]

    Gas chromatography (GC) and mass spectrometry (MS) were used to determine the stereoisomeric compositions of 6,10,14-trimethylpentadecan-2-ol and 6,10,14-trimethylpentadecan-2-one in wing extracts from 17 Bicyclus butterfly species from different regions of Africa. All samples were purified using solid phase extraction (SPE). Since some species contained both alcohol and ketone, these were separated and the ketone was reduced to the alcohol before analysis as either (R)-trans-chrysanthemoyl or (S)-2-acetoxypropionyl esters. A novel asymmetric synthesis was developed for a reference mixture of (2R/S,6S,10R)-6,10,14-trimethylpentadecan-2-ol with known composition of the eight stereoisomers. The mixture then was used as the (R)-trans-chrysanthemoyl esters to correlate each of the eight gas chromatographic peaks to a specific stereoisomer of the extracted wing compounds. Seven butterfly species showed (2R,6R,10R)-configuration of the alcohol, four species contained minute amounts of alcohol too small to determine the stereochemistry, nine species showed (6R,10R)-configuration of the ketone, and one species contained minute amounts of ketone too small to determine the stereochemistry. No other stereoisomers of alcohol or ketone could be detected in the extracts, and the quantities of the compounds in the wing extracts varied from 5 to 900 ng per sample for each species.

  • 48. Herz, Annette
    et al.
    Heitland, Werner
    Anderbrant, Olle
    Edlund, Helen
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    First use of pheromones to detect phenology patterns and density relationships of pine sawflies in German forests2000In: Agricultural and Forest Entomology, ISSN 1461-9555, E-ISSN 1461-9563, Vol. 2, no 2, p. 123-129Article in journal (Refereed)
    Abstract [en]

    1 Monitoring studies of pine sawflies with pheromone traps were performed for the first time in Germany. Pheromone traps baited with species-specific pheromone substances were installed in pine forests at different locations in Bavaria, Brandenburg and Lower Saxony during two years. 2 It was possible to track the flight phenology of Diprion pini, Gilpinia pallida and Neodiprion sertifer reliably and to get information about the number of generations of these species in 1997 and 1998. 3 A clear relationship between trap catch and population density could not be detected, but qualitative changes in trap catch caused by different density levels were observed. 4 For D. pini, trap catches were different among endemic populations of different forest types. Furthermore, catches of males reflected the results from the regular cocoon collections by foresters during the previous winter. 5 For N. sertifer, trap catches in endemic populations were well separated from trap catches on sites with higher sawfly densities. However, no significant correlation between trap catch and sawfly density or defoliation level could be found. These results suggest that the efficacy of the pheromone traps probably varied with biological features (sex ratio, density level, immigration) of the particular population.

  • 49. Holmberg, E
    et al.
    Holmquist, M
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Berglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Norin, Torbjörn
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Hult, K
    Reaction Conditions for the Resolution of 2-Methylalkanoic Acids in Esterification and Hydrolysis with Lipase from Candida cylindricea1991In: Applied Microbiology and Biotechnology, ISSN 0175-7598, Vol. 35, no 5, p. 572-578Article in journal (Refereed)
  • 50.
    Högberg, Hans-Erik
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Berglund, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Edlund, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Fägerhag, Jonas
    Hedenström, Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Lundh, Mårten
    Nordin, Ove
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Servi, S
    Vörde, Carin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Biocatalysis As A Useful Tool In Pheromone Synthesis: Enantiomerically Pure Building-Blocks From Bakers-Yeast Reductions And Enzyme-Catalyzed Resolutions1994In: Catalysis Today, ISSN 0920-5861, Vol. 22, no 3, p. 591-606Article in journal (Refereed)
123 1 - 50 of 122
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