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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.
    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)
  • 7.
    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.

  • 8. 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.

     

     

  • 9. Berglund, P
    et al.
    Vörde, Carin
    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.
    Esterification of 2-Methylalkanoic Acids Catalysed by Lipase from Candida rugosa: Enantioselectivity as a Function of Water Activity and Alcohol Chainlength1994In: Biocatalysis and Biotransformation, ISSN 1024-2422, E-ISSN 1029-2446, Vol. 9, p. 123-130Article in journal (Refereed)
  • 10.
    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)
  • 11.
    Berglund, Per
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Holmquist, M
    Hult, K
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Alcohols as Enantioselective Inhibitors in a Lipase Catalysed Esterification of a Chiral Acyl Donor1995In: Biotechnology Letters, ISSN 0141-5492, Vol. 17, no 1, p. 55-60Article in journal (Refereed)
  • 12. 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)
  • 13. 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)
  • 14. 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)
  • 15. Bhupinderpal-Singh,
    et al.
    Nordgren, A
    Ottosson Löfvenius, Mikael
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Mellander, Per- Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Högberg, P
    Large-scale girdling of Scots pine boreal forest reveals controls and estimates of mycorrhizal root soil heterotrophic respiration2003In: Proceedings Third International Symposium on the Dynamics of Physiological Processes in Woody Roots. Perth, Western Australia 29 Sept – 3 Oct, 2003, 2003Conference paper (Other scientific)
  • 16. Byers, J
    et al.
    Högberg, Hans-Erik
    Unelius, C. R.
    Birgersson, G.
    Löfqvist, J.
    Structure-Activity Studies on Aggregation Pheromone Components of Pithyogenes chalcographus (Coleoptera: Scolytidae): All stereoisomers of Chalcogran and Methyl 2,4-Decadienoate1989In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 15, no 2, p. 685-695Article in journal (Refereed)
  • 17. Bäckström, P
    et al.
    Bergström, G
    Björkling, F
    Hui-Zhu, H
    Högberg, Hans-Erik
    Jacobsson, Ulla
    Guo-Qiang, L
    Löfqvist, J
    Norin, Torbjörn
    Wassgren, A.-B.
    Structures, Absolute Configurations and Syntheses of the Volatile Signals from three Sympatric Ant-Lion Species, Euroleon nostras Grocus bore and Myrmeleon formicarius (Neuroptera: Myrmeleontidae).1989In: Journal of Chemical Ecology, ISSN 0098-0331, Vol. 15, no 1, p. 61-80Article in journal (Refereed)
  • 18. Bäckström, Peter
    et al.
    Björkling, Fredrik
    Högberg, Hans-Erik
    Norin, Torbjörn
    New three-step synthesis of racemic and optically active ipsdienol from myrcene1983In: Acta Chemica Scandinavica Ser. B: Organic Chemistry and Biochemistry, ISSN 0302-4369, Vol. B37, no 1, p. 1-5Article in journal (Refereed)
  • 19. Bäckström, Petre
    et al.
    Björkling, Fredrik
    Högberg, Hans-Erik
    Norin, Torbjörn
    Cross-coupling of vinyl cuprates and allylic halides and synthesis of the Comstock Mealybug pheromone via photooxidation 2,6-dimethyl-2,5-heptadiene.1984In: Acta Chemica Scandinavica Ser. B - Organic chemistry and Biochemistry, ISSN 0302-4369, Vol. B38, no 9, p. 779-782Article in journal (Refereed)
  • 20. D'Arrigo, P
    et al.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Pedrocchi-Fantoni, G
    Servi, S
    Old and New Synthetic Capacities of Baker's Yeast1994In: Biocatalysis, ISSN 0886-4454, Vol. 9, no 1-4, p. 299-312Article in journal (Refereed)
  • 21.
    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)
  • 22.
    Eriksson, Carina
    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.
    Månsson, Per
    Schlyter, Fredrik
    Sjödin, Kristina
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Strategier i sökandet efter gnaghämmare mot snytbaggen, Hylobius abietis: Föredrag, 19:e Organikerdagarna i Linköpng 20042004Conference paper (Other academic)
  • 23.
    Eriksson, Carina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Schlyter, F
    Sjödin, Kristina
    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.
    Syntes av 2,6-disubstituerade piperidinalkaloider, potentiella gnaghämmare mot snytbaggen Hylobius abietis: 20:e Organikerdagarna, 12-15 juni 2006, Kalmar, föredrag2006Conference paper (Other academic)
  • 24.
    Eriksson, Carina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Sjödin, Kristina
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Schlyter, Fredrik
    Swedish University of Agricultural Sciences, Alnarp.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Synthesis of (+)- and (-)-dihydropinidine by diastereoselective dimethylzinc promoted allylation of 2-methyltetrahydropyridine-N-oxide with allylboronic ester.2006In: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 17, no 7, p. 1074-1080Article in journal (Refereed)
    Abstract [en]

    The enantiomers of the naturally occurring alkaloid dihydropinidine 1, potential antifeedants against the pine weevil, Hylobius abietis, were prepared by diastereoselective, dimethylzinc mediated addition of pinacolyl 2-propenylboronate 14 to nitrones (R)- and (S)-2-methyl tetrahydropyridine-N-oxide 3, prepared from d- and l-alanine, respectively.

  • 25.
    Eriksson, Carina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Smitt, O.
    Schlyter, F.
    Sjödin, Kristina
    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.
    Antifeedants for Protection of Pines and Spruces against the Pine Weevil, Hylobius abietis: International Society of Chemical Ecology, Annual Meeting 2001, Lake Tahoe, USA2001Conference paper (Other academic)
  • 26.
    Eriksson, Carina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Smitt, Olof
    Schlyter, Fredrik
    Sjödin, Kristina
    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.
    Searching for Pine Weevil Antifeedants, Strategy and Synthesis2002In: 19th annual meeting of International Society of Chemical Ecology, 2002, Hamburg, Germany, 2002, p. 217-Conference paper (Other academic)
  • 27.
    Friman, Linda
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Höglund, Hans
    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.
    Agnemo, Roland
    Tannin-iron impregnated thermomechanical pulp: Part I: Effects of extractions and heat on brightness2004In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 19, no 2, p. 229-236Article in journal (Refereed)
    Abstract [en]

    Tannins are polyphenolic compounds found mainly in bark. When reacting with iron, they form strongly coloured complexes, which through contamination from the bark may induce a brightness decrease of mechanical pulps. Wood itself contains phenolic compounds, which can form coloured complexes with iron. We have investigated gallotannin as a model for metal-binding sites in the pulp. The behaviour of tannin-iron complexes in solution and in pulp has been studied. In aqueous solution, the tannin-iron complexes can be decolourised by the addition of diethylenetriaminepentaacetic acid (DTPA). The colour of the tannin-iron complexes was very pH-dependent. Thus in solution, these were decolourised at low pH and at high pH the spectral characteristics were changed substantially. We have studied the effects on brightness and heatinduced brightness loss of the impregnation of thermomechanical pulp (TMP) with 30 parts per million iron (ppm i.e. mg/kg) either as iron or tannin-iron as well as the possibility to decrease such effects by using various solvent extractions. The tannin-iron impregnation causes a decrease in ISO-brightness of approximately 3% and an increase in the light absorption coefficient (k) by approximately 2 m(2)/kg at the tannin-iron absorbance maximum. 565 run. These effects are approximately ten times higher than those observed for the Pulp only impregnated with iron. Extraction with 1% by weight of DTPA provides a way to reduce the brightness decrease induced by the tanniniron complexes and the observed decrease can be attributed to removal of iron from the pulp. Acid extraction was the most efficient way to reduce the iron content in the pulps and to decoulorise the tannin-iron impregnated pulp. However, after acid extraction of iron impregnated Pulps, new chromophores were evidently formed. Addition of the reducing agent, sulphite, to extractions had no effect on the iron removal or the brightness of the impregnated pulps. The heat-induced brightness loss is not influenced by the addition of tannin-iron or iron. The brightness loss caused by heat was lower for pulps extracted with DTPA.

  • 28.
    Friman, Linda
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Höglund, Hans
    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.
    Agnemo, Roland
    Tannin-iron impregnated thermomechanical pulp: Part II: Bleachability and brightness reversion2004In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 19, no 4, p. 525-531Article in journal (Refereed)
    Abstract [en]

    Tannins are polymeric, phenolic constituents found in the bark of pine and spruce. When reacting with iron ions, tannins form strongly coloured complexes. Thus, the presence of bark in the mechanical pulping process leads to decreased brightness of the pulp. In order to evaluate the effects of the presence of iron on the properties of pulp, we have impregnated thermomechanical pulp (TMP) with 30 parts per million (ppm i.e. mg/kg) iron either as Fe3+ or as tannin-iron complexes and studied how such treatments affect bleachability and heat-induced brightness reversion. The bleaching agents studied are hydrogen peroxide and sodium dithionite. Treatment of the tannin-iron impregnated pulp with 1% by weight of diethylenetriaminepentaacetic acid (DTPA) before bleaching with 4% hydrogen peroxide almost eliminated the brightness loss caused by the impregnation. Such a treatment also removed all of the added iron from both the tannin-iron and FeCl3 impregnated pulps. Approximately 5% more of the added peroxide was required for oxidation of the tannins in the tannin-iron impregnated pulp. Contrary to what was observed with peroxide bleaching, dithionite bleaching did not reduce the amount of iron in the pulps. Instead, the added iron and tannin-iron negatively affected the dithionite bleaching, even if the pulps were extracted with DTPA before bleaching. It should therefore be advantageous to first bleach with peroxide, which removes most of the iron, and then with dithionite. Compared with dithionite, peroxide yields a more efficient bleaching. The reason for this is that the former reduces the light absorption coefficient, the k-value, more efficiently in the whole visible spectrum, whereas dithionite reduces it mainly at shorter wavelengths. In our experiments, the addition of tannin-iron or FeCl3 to the untreated pulp did not increase heat-induced brightness reversion. This is Supported by the fact that although extraction of the samples with DTPA before bleaching lowered the iron content slightly, it-did not affect the brightness reversion. The initial brightness reversion of the dithionite bleached pulps was larger than that observed for the peroxide bleached pulps.

  • 29.
    Friman, Linda
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Logenius, Louise
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Agnemo, Roland
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Comparison of metal profiles in thermomechanical pulping processes in which either hydrogen peroxide or dithionite bleaching is used2003In: Paperi ja Puu/Paper and timber, ISSN 0031-1243, Vol. 85, no 6, p. 334-339Article in journal (Refereed)
  • 30. Fronza, G.
    et al.
    Fuganti, C.
    Pedrocchi-Fantoni, G.
    Högberg, Hans-Erik
    Servi, S.
    Chiral Alpha-Methyl-homoallylic alcohols from Yeast-generated Precursors: Synthesis of (4S,5R)-Sitophilure1988In: Chemistry Letters, ISSN 0366-7022, Vol. 1988, no 3, p. 385-388Article in journal (Refereed)
  • 31. Fuganti, C
    et al.
    Grasselli, P
    Servi, S
    Högberg, Hans-Erik
    Bakers Yeast Mediated Preparation of (S)-3-(2-Furyl)- 2-methyl-1-propanol a Bifunctional Chiral C5 Isoprenoid Synton. Synthesis of (4R,8R)-4,8-Dimethyldecanal, Pheromone of Tribolium castaneum.1988In: Journal of the Chemical Society. Perkin Transactions I, ISSN 0300-922X, Vol. 1988, no 12, p. 3061-3065Article in journal (Refereed)
  • 32. Fuganti, C.
    et al.
    Grasselli, P.
    Servi, S.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Fermenting Bakers' yeast reduction of a-methyl-b-(2-furyl)acrolein1992-1997In: Preparative biotransformations: whole cell and isolated enzymes in organic systems, 1992-1997, p. 1-7Chapter in book (Other scientific)
  • 33. 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)
  • 34.
    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)
  • 35.
    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)
  • 36.
    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)
  • 37. Hillbur, Ylva
    et al.
    Andersson, Peter
    Arn, Heinrich
    Bengtsson, Marie
    Löfqvist, Jan
    Biddle, Anthony J.
    Smitt, Olof
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Plass, Ernst
    Franke, Stephan
    Francke, Wittko
    Identification of sex pheromone components of the pea midge, Contarinia pisi (Diptera: Cecidomyiidae)1999In: Naturwissenschaften, ISSN 0028-1042, Vol. 86, no 6, p. 292-294Article in journal (Refereed)
  • 38. Hjalmarsson, Mats
    et al.
    Högberg, Hans-Erik
    Synthesis of (R)- and (S)-10-Methyldodecyl Acetate, Sex Pheromone Components of the Smaller Tea Tortrix Moth (Adoxyphyes sp.), from Chiral Synthons Prepared via Asymmetric Synthesis.1985In: Acta Chemica Scandinavica Series B, ISSN 0302-4369, Vol. 39, no 9, p. 793-796Article in journal (Refereed)
  • 39. 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)
  • 40.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Alkylation of Amide Enolates1995In: Methoden der organischen Chemie : Additional and supplementary volumes of the 4th edition ; Vol. E21, Stereoselective synthesis, 1995, p. 791-915Chapter in book (Other scientific)
  • 41.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Approaches to 2-Methylalkanols of High Enantiomeric Purities via Enzyme mediated reactions.1992In: Microbial Reagents in Organic Synthesis: NATO Advanced Research Workshop on Microbial Reagents in Organic Synthesis (Sestri Levante : 1992), Dordrecht: Klüwer Academic Publishers , 1992, p. 399-410Conference paper (Other scientific)
  • 42.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Biosignal and Organic Chemistry: IOBC wprs Working Group Meeting - The Scanian Journey. Pheromones and Other Semiochemicals in Integrated Production. Lund, September 9-14, 2007. Lecture2007Conference paper (Other scientific)
    Abstract [en]

    The role of organic Synthesis in the Mistra-program Biosignal.

  • 43.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Ekologisk kemi: Enantioselektiv syntes av några seskvi och diterpener: 20:e Organikerdagarna, 12-15 juni 2006, Plenary lecture2006Conference paper (Other scientific)
  • 44.
    Högberg, Hans-Erik
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Exploiting enantioselectivity of hydrolases in organic solvents2008In: Organic Synthesis with Enzymes in Non-Aqueous Media, Weinheim: Wiley-VCH Verlagsgesellschaft, 2008, p. 73-112Chapter in book (Other academic)
    Abstract [en]

    In modern organic chemistry the synthesis of chiral enantiopure compounds is an extremely important objective. To achieve this, biocatalysts have emerged as key tools. The broad reactivity of hydrolytic enzymes combined with their ability to discriminate between enantiomers make them ideal catalysts for resolving racemic organic compounds to provide enantiomerically enriched products. This chapter gives an overview of how the enantioselectivity of hydrolases can be exploited to furnish virtually enantiopure compounds via kinetic resolution of racemic compounds and desymmetrisation of symmetric compounds. Enantioselectivity and E-values are discussed. Reversibility of hydrolase-catalysed reactions and how it can be avoided by using various irreversible acyl donors as well as the determination and optimization of enantioselectivity are briefly discussed. The bulk of the chapter consists of selected examples of hydrolase catalysed reactions of some important classes of compounds. Thus the usefulness of hydrolase-catalyzed reactions is demonstrated by several examples of reactions in organic solvents of primary, secondary, tertiary alcohols, various amines, and acid derivatives.

  • 45.
    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)
  • 46.
    Högberg, Hans-Erik
    et al.
    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.
    Berglund, Per
    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.
    Water Activity Influences Enantioselectivity in a Lipase Catalysed Resolution by Esterification in an Organic Solvent1993In: Tetrahedron: Asymmetry, ISSN 0957-4166, Vol. 4, no 10, p. 2123-2126Article in journal (Refereed)
  • 47.
    Högberg, Hans-Erik
    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.
    Fägerhag, Jonas
    Servi, S
    Enantioselective Synthesis Of (S)-2-Methyl-1-Alkanols Via Bakers-Yeast Mediated Reduction Of Alpha-Methyl-2-Thiophenepropenals1992In: Journal of Organic Chemistry, ISSN 0022-3263, Vol. 57, no 7, p. 2052-2059Article in journal (Refereed)
  • 48.
    Högberg, Hans-Erik
    et al.
    Högskolan i Sundsvall / Härnösand.
    Hedenström, Erik
    Isaksson, R
    Wassgren, A.-B.
    Preparation of the Four Stereoisomers of Chalcogran, Pheromone Component of Pityogenes chalcographus and of both Enantiomers of γ-Caprolactone, Pheromone Component of Trogoderma granarium.1987In: Acta Chemica Scandinavica Series B, ISSN 0302-4369, Vol. 41, no 9, p. 694-697Article in journal (Refereed)
  • 49.
    Högberg, Hans-Erik
    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.
    Nordin, Ove
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
    Enantioselective Transesterifications of 2-Methyl-1-alcohols Catalysed by Lipases from Pesudomonas1994In: Tetrahedron: Asymmetry, ISSN 0957-4166, Vol. 5, no 5, p. 785-788Article in journal (Refereed)
  • 50.
    Högberg, Hans-Erik
    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.
    Wassgren, A.-B.
    Hjalmarsson, Mats
    Bergström, Gunnar
    Löfqvist, Jan
    Norin, Torbjörn
    Synthesis and Gas Chromatographic Separation of the eight Stereoisomers of Diprionol and their Acetates, Components of the Sex Pheromone Pine Sawflies1990In: Tetrahedron, ISSN 0040-4020, Vol. 46, no 8, p. 3007-3018Article in journal (Refereed)
123 1 - 50 of 106
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