lnu.sePublications
Change search
Refine search result
12 1 - 50 of 83
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Anderbrant, Olle
    et al.
    Matteson, Donald S.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Pharazyn, Philip S
    Santangelo, Ellen M.
    Schlyter, Fredrik
    Birgersson, Göran
    Pheromone of the elm bark beetle Scolytus laevis (Coleoptera: Scolytidae): stereoisomers of 4-methyl-3-heptanol reduce interspecific competition2010In: Chemoecology, ISSN 0937-7409, E-ISSN 1423-0445, Vol. 20, no 3, p. 179-187Article in journal (Refereed)
    Abstract [en]

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

  • 2.
    Baeckstrom, P.
    et al.
    KTH, Stockholm.
    Jacobsson, U.
    KTH, Stockholm.
    Norin, T.
    KTH, Stockholm.
    Unelius, C. R.
    KTH, Stockholm.
    Synthesis and Characterization of All 4 Isomers of Methyl 2,4-Decadienoate for an Investigation of the Pheromone Components of Pityogenes-Chalcographus1988In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 44, no 9, p. 2541-2548Article in journal (Refereed)
  • 3.
    Baeckstrom, P.
    et al.
    KTH, Sweden.
    Li, L.
    KTH, Sweden.
    Polec, I.
    Unelius, C. Rikard
    KTH, Sweden.
    Wimalasiri, W. R.
    Convenient Method for the Synthesis of Lineatin, a Pheromone Component of Trypodendron-Lineatum1991In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 56, no 10, p. 3358-3362Article in journal (Refereed)
    Abstract [en]

    Synthesis of racemic lineatin (1), a pheromone component of Trypodendron lineatum, is described. Condensation of 5-methyl-5-hexen-2-one (2) and triethyl phosphonoacetate with LiN(SiMe3)2 gave esters 3, which upon hydrolysis gave acids 4a-f. The bicyclo[3.2.0] ring compounds 5 and 6 were obtained via an intramolecular [2 + 2] addition by refluxing underivatized carboxylic acids 4a-f with NaOAc and Ac2O. Compound 5 was isomerized to the thermodynamically more stable isomer 6 using a Pd/C catalyst activated with hydrogen. Reduction of 6 with LiAlH4 gave the endo and exo isomers 7a and 7b (4:1). Isolation of the alcohol 7a followed by acetylation gave 8. Subsequent oxidation with OsO4 and methylmorpholine N-oxide gave diol 9. Cleavage of 9 with H5IO6 in diethyl ether gave keto aldehyde 10, which was converted to keto acetal 11. Treatment of 11 with MeMgBr followed by acidic workup gave 1. The overall efficiency is approximately 20%.

  • 4.
    Bengtsson, Marie
    et al.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Boutitie, Anne
    SUAMME, Mas de Saporta, Lattes, France.
    Jósvai, Julia
    Plant Protection Institute MTA ATK, Budapest, Hungary.
    Toth, Miklos
    Plant Protection Institute MTA ATK, Budapest, Hungary.
    Andreadis, Stefanos
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Rauscher, Stefan
    Swiss Federal Research Station, Wädenswil, Switzerland.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Witzgall, Peter
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Pheromone races of Cydia splendana (Lepidoptera, Tortricidae) overlap in host plant association and geographic distribution2014In: Frontiers in Ecology and Evolution, E-ISSN 2296-701X, Vol. 2, p. Article ID: 46-Article in journal (Refereed)
    Abstract [en]

    Identification of the sex pheromone of Cydia splendana (Lepidoptera, Tortricidae) bypheromone gland analysis followed by field trapping with synthetic compounds showsthe occurrence of two pheromone races. Acorn moth females from Sweden, whereoak Quercus robur is the only host plant, use a blend of the E,Z and E,E isomers of8,10-dodecadien-1-yl acetate. In Central and Southern Europe, where C. splendana feedson chestnut Castanea sativa and several species of oak, males respond to another isomerblend, E,E and Z,E. The distribution of the two pheromone races of C. splendana overlapsin Northern France, where they share oak as plant host. Differences in sex communicationsignals between these populations of C. splendana corroborate the role of specific materecognition in speciation events.

  • 5.
    Bergström, Maria
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Ganji, Suresh
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Naidu Veluru, Ramesh
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    N-Iodosuccinimide (NIS) in Direct Aromatic Iodination2017In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, no 22, p. 3234-3239Article in journal (Refereed)
    Abstract [en]

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

  • 6.
    Bjorkling, F.
    et al.
    KTH, Stockholm.
    Norin, T.
    KTH, Stockholm.
    Unelius, C. Rikard
    KTH, Stockholm.
    Synthesis of 8z,10z-Dodecadienyl Acetate Using a General Method Applicable to Z,Z-1,3-Dienes1985In: Synthetic Communications, ISSN 0039-7911, E-ISSN 1532-2432, Vol. 15, no 6, p. 463-472Article in journal (Refereed)
  • 7.
    Bjorkling, F.
    et al.
    KTH, Stockholm.
    Norin, T.
    KTH, Stockholm.
    Unelius, C. Rikard
    KTH, Stockholm.
    Miller, R. B.
    Univ. of California, Davis, USA.
    A Stereospecific Synthesis of All 4 Isomers of 9,11-Tetradecadienyl Acetate Using a General-Method Applicable to 1,3-Dienes1987In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 52, no 2, p. 292-294Article in journal (Refereed)
  • 8. Bohman, B
    et al.
    Nordlander, G
    Nordenhem, H
    Sunnerheim, K
    Borg-Karlson, A-K
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Structure - activity relationships of phenyl propanoids as antifeedants for the pine weevil Hylobius abieist2008In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 34, no 3, p. 339-352Article in journal (Refereed)
  • 9.
    Bohman, Björn
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Cavonius, Lillie
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Unelius, C. Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Vegetables as biocatalysts in stereoselective hydrolysis of labile organic compounds2009In: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 11, no 11, p. 1900-1905Article in journal (Refereed)
    Abstract [en]

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

  • 10.
    Bohman, Björn
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. University of Western Australia, Australia.
    Flematti, Gavin R.
    University of Western Australia, Australia.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Practical one-pot stereospecific preparation of vicinal and 1,3-diols2017In: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 58, no 1, p. 75-77Article in journal (Refereed)
    Abstract [en]

    A facile one-pot synthesis providing vicinal diols and 1,3-diols in >95% stereoisomeric purity from commercially available enantiopure hydroxy esters has been developed. The esters were reduced with DIBALH and alkylated in situ with 4-pentenylmagnesium bromide, which after workup generated the title diols as diastereomeric pairs. These pairs were easily separated by preparative chromatography, affording products with retained stereoisomeric purity from the starting materials. This method represents an expedient preparation of many common natural products, such as cerambycid beetle pheromones and intermediates towards bicyclic acetal bark beetle pheromones. (C) 2016 Elsevier Ltd. All rights reserved.

  • 11.
    Bohman, Björn
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Troger, A.
    University of Hamburg.
    Franke, S.
    University of Hamburg.
    Lorenzo, M. G.
    Fiocruz, Belo Horizonte, Brazil.
    Francke, W.
    University of Hamburg.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Structure Elucidation and Synthesis of Dioxolanes Emitted by Two Triatoma Species (Hemiptera Reduviidae)2011In: Journal of natural products (Print), ISSN 0163-3864, E-ISSN 1520-6025, Vol. 74, no 4, p. 690-694Article in journal (Refereed)
    Abstract [en]

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

  • 12.
    Bohman, Björn
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Unelius, C. Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Synthesis of all four stereoisomers of 5-hydroxy-4-methyl-3-heptanone using plants and oyster mushrooms2009In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 65, no 42, p. 8697-8701Article in journal (Refereed)
    Abstract [en]

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

  • 13.
    Bohman, Björn
    et al.
    Univ Western Australia, Australia.
    Weinstein, Alyssa M.
    Australian Natl Univ, Australia.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Lorenzo, Marcelo G.
    Fiocruz MS, Brazil.
    Attraction of Rhodnius prolixus males to a synthetic female-pheromone blend2018In: Parasites & Vectors, ISSN 1756-3305, E-ISSN 1756-3305, Vol. 11, article id 418Article in journal (Refereed)
    Abstract [en]

    Background: The triatomine bug Rhodnius prolixus Stal, 1859 (Heteroptera: Reduviidae) is the primary vector of Chagas disease in Colombia and Venezuela. An important step in controlling Chagas disease is monitoring the growth and spread of bug populations to inform effective management. Such monitoring could be carried out using pheromone traps. To develop effective pheromone traps, it is vital to understand the pheromone chemistry of R. prolixus. Previous studies have found that female R. prolixus metasternal gland secretions induce males to: leave shelters, take off, orientate during walking, aggregate around mating pairs, and mate. This study aims to identify a synthetic blend of female metasternal gland compounds that could be used to attract R. prolixus. Results: We investigated the electrophysiological activity of the ten most abundant compounds in female R. prolixus metasternal glands using single sensillum recordings. In total we obtained 60 recordings from basiconic sensilla in male R. prolixus. In 31 of these recordings, responses to individual compounds were observed. Each of the ten tested compounds elicited neuron responses in a minimum of eight recordings. Having confirmed their electrophysiological activity, we tested these ten compounds by presenting them to male Rhodnius prolixus in a 7 olfactometer. Male bugs showed a significant preference for the blend of metasternal gland compounds compared to the clean air control. Conclusions: A simple blend of ten compounds found in female R. prolixus metasternal glands is attractive to conspecific males. All compounds in the blend are either commercially available at low cost, or easily synthetically prepared from simple precursors. We hope that this blend will be evaluated as a lure for pheromone traps in field bioassays.

  • 14.
    Borg Karlson, A. K.
    et al.
    KTH, Sweden.
    Unelius, C. Rikard
    KTH, Sweden.
    Valterova, I.
    KTH, Sweden.
    Nilsson, L. A.
    Floral fragrance chemistry in the early flowering shrub Daphne mezereum1996In: Phytochemistry, ISSN 0031-9422, E-ISSN 1873-3700, Vol. 41, no 6, p. 1477-1483Article in journal (Refereed)
    Abstract [en]

    The floral fragrance of the shrub Daphne mezereum in central Sweden was collected by means of the head-space technique and investigated by GC-MS and multi-dimensional GC. (S)-(+)-Linalool was the main constituent (95%) of the flower fragrance and its enantiomeric purity exceeded 99% in the samples. The (2S, 5S)- and (2R, 5S)-furanoid and the (3R, 6S)- and (3S, 6S)-pyranoid linalool oxide isomers constituted 2-5% of the fragrance. The elution order of these compounds on a permethylated beta-cyclodextrin column is reported. A fragrance sample of D. mezereum as well as (S)-(+)-linalool attracted males of the vernal solitary bee species Colletes cunicalarius and Andrena cinerea. A racemic mixture of the two enantiomeric pairs of known furanoid linalool oxides was only weakly attractive to the bees. The role of the fragrance in the pollination specialization of the plant is discussed.

  • 15.
    Borgkarlson, A. K.
    et al.
    KTH, Sweden.
    Englund, F. O.
    KTH, Sweden.
    Unelius, C. Rikard
    KTH, Sweden.
    Dimethyl Oligosulphides, Major Volatiles Released from Sauromatum Guttatum and Phallus-Impudicus1994In: Phytochemistry, ISSN 0031-9422, E-ISSN 1873-3700, Vol. 35, no 2, p. 321-323Article in journal (Refereed)
    Abstract [en]

    The odour released from the flower of the voodoo lily Sauromatum guttatum Araceae and the odour of the mushroom Phallus impudicus Phallaceae were analysed. The two species had the major constituents dimethyl disulphide and dimethyl trisulphide in common. Other major components of the S. guttatum excretion were beta caryophyllene, dimethyl sulphide, dimethyl tetrasulphide, indole and skatole. Linalool, trans-ocimene, and phenylacetaldehyde were released by P. impudicus.

  • 16. Borg-Karlson, A K
    et al.
    Nordlander, R
    Mudalige, A
    Nordenhem, Henrik
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Antifeedants in the feces of the pine weevil Hylobius abietis: Identification and biological activity2006In: Journal of chemical ecology, Vol. 32, no 5, p. 943-957Article in journal (Refereed)
  • 17.
    Brown, Robert L.
    et al.
    The New Zealand Institute for Plant & Food Research Ltd, New Zealand ; University of Auckland, New Zealand.
    El-Sayed, Ashraf M
    The New Zealand Institute for Plant & Food Research Ltd, New Zealand.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. The New Zealand Institute for Plant & Food Research Ltd, New Zealand.
    Beggs, Jacqueline R
    University of Auckland, New Zealand.
    Suckling, David M
    The New Zealand Institute for Plant & Food Research Ltd, New Zealand ; University of Auckland, New Zealand.
    Invasive Vespula Wasps Utilize Kairomones to Exploit Honeydew Produced by Sooty Scale Insects, Ultracoelostoma.2015In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 41, no 11, p. 1018-1027Article in journal (Refereed)
    Abstract [en]

    Vespula wasps are widely distributed invasive alien species that are able to reach high population densities in the 1.2 M ha of beech forests (Fuscospora spp.) of New Zealand's South Island. These endemic temperate forests have an abundance of carbohydrate-rich honeydew produced by native scale insects (Ultracoelostoma spp.). A characteristic aroma is associated with the honeydew in beech forests, which we hypothesized is the signal used by wasps to harvest the vast resources previously exploited by birds and other insects. Volatile collections were taken of black beech tree trunks with honeydew and sooty mold present, and analyzed with a gas chromatograph-mass spectrometer. Eleven compounds (benzaldehyde, benzyl alcohol, 2-phenylethyl acetate, 2-phenylethanol, phenylacetaldehyde, methyl 2-phenylacetate, ethyl 2-phenylacetate, methyl salicylate, n-octanol, octan-3-ol, and 1-octen-3-ol) were positively identified from the headspace, and were shown to elicit an electrophysiological response from Vespula vulgaris worker antennae by using electroantennography (EAG). Field trials with delta traps individually baited with these compounds confirmed wasp attraction to 8 of the 11 compounds tested, with 2-phenylethyl acetate, methyl salicylate, and octan-3-ol capturing the same numbers of wasps as the control. In later trials, attraction to a 1:1 blend of benzaldehyde and n-octanol was significantly higher (45 %) than to any other treatment. Many of the chemicals identified are known to be associated with fermenting sugars, or with fungal aroma. Benzaldehyde and n-octanol are common compounds produced by many different species in nature. The ability to respond to generic signals emanating from sugar resources is likely to contribute to the success of V. vulgaris as an invasive species.

  • 18.
    Brown, Robert L.
    et al.
    New Zealand Inst Plant & Food Res Ltd.
    El-Sayed, Ashraf M.
    New Zealand Inst Plant & Food Res Ltd.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Suckling, David M.
    New Zealand Inst Plant & Food Res Ltd.
    Attraction of the invasive social wasp, Vespula vulgaris, by volatiles from fermented brown sugar2014In: Entomologia Experimentalis et Applicata, ISSN 0013-8703, E-ISSN 1570-7458, Vol. 151, no 2, p. 182-190Article in journal (Refereed)
    Abstract [en]

    The introduction of invasive social wasp species of the genus Vespula (Hymenoptera: Vespidae) to New Zealand has caused a major ecological problem, particularly in the beech forests (Nothofagus spp.) of the South Island, where they have destabilized the native bird and invertebrate biodiversity. New attractants are under investigation as part of a search for pest management solutions. Fermenting brown sugar has been previously reported as a social wasp attractant. This work was undertaken to identify compounds from fermented brown sugar attractive to social wasps. Raw fermented brown sugar was confirmed to be attractive in a field trial and 10 chemical compounds present in the headspace were positively identified by coupled gas chromatography-mass spectrometry and synthetic references. During electroantennogram experiments, 3-methyl-1-butanol, 3-methylbutyl acetate, and ethyl hexanoate elicited high electrophysiological responses from Vespula vulgaris (L.) antennae. These compounds mediated attraction of V.vulgaris wasps in forest margins by trapping. A blend of these compounds could be used as a lure in a monitoring tool, or even a local suppression method if combined with a toxin.

  • 19.
    Byers, J. A.
    et al.
    SLU, Alnarp.
    Hogberg, H. E.
    Midsweden University, Sundsvall.
    Unelius, C. Rikard
    KTH, Stockholm.
    Birgersson, G.
    SLU, Alnarp.
    Lofqvist, J.
    SLU, Alnarp.
    Structure Activity Studies on Aggregation Pheromone Components of Pityogenes-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)
  • 20.
    Bäckman, A. C.
    et al.
    SLU, Sweden.
    Anderson, P.
    SLU, Sweden.
    Bengtsson, M.
    SLU, Sweden.
    Löfqvist, J.
    Unelius, C. Rikard
    KTH, Sweden.
    Witzgall, P.
    SLU, Sweden.
    Antennal response of codling moth males, Cydia pomonella L. (Lepidoptera: Tortricidae), to the geometric isomers of codlemone and codlemone acetate2000In: Journal of Comparative Physiology A. Sensory, neural, and behavioral physiology, ISSN 0340-7594, E-ISSN 1432-1351, Vol. 186, no 6, p. 513-519Article in journal (Refereed)
    Abstract [en]

    Single sensillum recordings from Cydia pomonella male antennae showed three different types of receptor neurons. The most abundant type was most sensitive to the main pheromone compound (E,E)-8,10-dodecadienol, while its response to the geometric isomers E,Z, Z,E and Z,Z was comparable to a tenfold lower dose of (E,E)-8,10-dodecadienol. This neuron type also responded to the four behaviorally antagonistic isomers of (Delta,Delta)-8,10-dodecadienyl acetate, among which it was most sensitive to the E,E isomer. Cross-adaptation studies showed that these compounds were all detected by the same receptor neuron type. Receptor neurons specifically tuned to (E,Z) or (Z,Z)-8,10-dodecadienol were not found, although these two compounds are behaviorally active. A second type of receptor neuron responded to all isomers of (Delta,Delta)-8,10-dodecadienyl acetate and was most sensitive to the E,E isomer. This neuron type did not respond to any of the isomers of (Delta,Delta)-8,10-dodecadienol. A third receptor neuron type was highly sensitive to the plant compound alpha-farnesene. The finding that the receptor neuron type tuned to the main pheromone compound responded even to strong behavioral antagonists aids the interpretation of ongoing behavioral studies for the development of the mating disruption technique in codling moth.

  • 21. Correa, A. G.
    et al.
    Batista-Pereira, L. G.
    Santangelo, E. M.
    KTH, Sweden.
    Stein, K.
    Unelius, C. Rikard
    Eiras, A. E.
    Electrophysiological studies and identification of possible sex pheromone components of Brazilian populations of the sugarcane borer, Diatraea saccharalis2002In: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 57, no 7-8, p. 753-758Article in journal (Refereed)
    Abstract [en]

    Virgin female gland extracts of sugarcane moth Diatraea saccharalis (Fabricius) (Lepidoptera: Pyralidae), from three locations in Brazil, have been analyzed. By GC-MS analysis and comparison of the chromatographic retention time of the components of the pheromone gland with those retention times of synthetic standards, we observed the presence of (Z)-hexadec-11-enal (1), hexadecanal (2), (9E,11E)-hexadecadienal (4), (9Z,11Z)-hexadecadienal (5) and (9E,11E)-hexadecadienal (6), as minor components besides the major constituent (9Z,11E)-hexadecadienal (3) already reported. We found no variations in the composition of the gland extracts deriving from the three Brazilian populations and only two compounds, (Z)-hexadec-11-enal (1) and (9Z,11E)-hexadecadienal (3), elicited antennal responses (GC-EAD). In electroantennography (EAG), however, pure compounds 1 and 3, a binary mixture containing 1 and 3, and a mixture containing all of the six synthetic compounds 1-6 elicited a depolarization in male antennae of D. saccharalis, without any statistically different delay. The EAG responses to the other isomers of 9,11-hexadecadienal were small and not significantly different from the control, except for the (9Z,11Z)-isomer (5) which showed an relatively strong electroantennal activity.

  • 22.
    Eiras, A. E.
    et al.
    Brazil.
    Kovaleski, A.
    Vilela, E. F.
    Chambon, J. P.
    Unelius, C. Rikard
    KTH, Sweden.
    Borg-Karlson, A. K.
    KTH, Sweden.
    Liblikas, I.
    KTH, Sweden.
    Mozuraitis, R.
    KTH, Sweden.
    Bengtsson, M.
    SLU, Sweden.
    Witzgall, P.
    SLU, Sweden.
    Sex pheromone of the Brazilian apple leafroller, Bonagota cranaodes Meyrick (Lepidoptera, Tortricidae)1999In: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 54, no 7-8, p. 595-601Article in journal (Refereed)
    Abstract [en]

    The female sex pheromone of Bonagota (=Phthteochroa) cranaodes (Meyrick) is a blend of (E,Z)-3,5-dodecadienyl acetate (E3,Z5-12:Ac) and (Z)-9-hexadecenyl acetate (Z9-16:Ac) according to analysis of pheromone - gland extracts and field trapping in apple orchards. This is the first time that E3,Z5-12:Ac has been identified as a lepidopteran sex pheromone. Traps baited with 100 mu g E3,Z5-12:Ac were attractive over 15 weeks in the field and were as effective as traps baited with virgin females. Addition of Z9-16:Ac to E3,Z5-12:Ac at ratio of 1:10 had a significantly increase of male moths. The addition of the Z,E and Z:Z isomers to rubber septa baited with E3,Z5-12:Ac did not modify B. cranaodes male attraction, but 10% of EE enhanced trap catch.

  • 23. El-Sayed, A.
    et al.
    Liblikas, I.
    KTH, Sweden.
    Unelius, C. Rikard
    Flight and molecular modeling study on the response of codling moth, Cydia pomonella (Lepidoptera: Tortricidae) to (E,E)-8,10-dodecadien-1-ol and its geometrical isomers2000In: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 55, no 11-12, p. 1011-1017Article in journal (Refereed)
    Abstract [en]

    In a previous study we have reported that both (E,Z)-8,10-dodecadienol (E,Z) and (Z,Z) 8,10-dodecadienol (Z,Z) isomers inhibit the attraction of male codling moth, Cydia pomonella L. when added to (E,E)-8,10-dodecadienol (E,E) while the (Z,E)-8,10-dodecadienol (Z,E) isomer induces slight increase in the number of males attracted to the pheromone source. In the present study, we have tested the behavioral activity of the individual geometrical isomers E,Z; Z,E and Z,Z. A few number of codling moth males flew to the Z,E-isomer while the other two isomers (i.e. E,Z and Z,Z) did not elicit any upwind orientation. Analysis of the Right behavior to the E,E- and Z,E-isomer showed significant differences in most of the flight parameters evaluated. Based on the biological observations and molecular modeling, we suggest that the behavioral activity of the Z,E-isomer is due to presence of specific receptors for this isomer on male antennae and not to its structural resemblance to the E,E-isomer. These results underline the importance of the Z,E-isomer in sex attraction of male codling moth.

  • 24.
    El-Sayed, A. M.
    et al.
    Southern Crop Protection and Food Research Centre, Canada.
    Delisle, J.
    Canadian Forest Service, Canada.
    De Lury, N.
    Pacific Agri-Food Research Centre, Canada.
    Gut, L. J.
    Michigan State University, USA.
    Judd, G. J. R.
    Pacific Agri-Food Research Centre, Canada.
    Legrand, Sacha
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Reissig, W. H.
    New York State Agricultural Experiment Station, USA.
    Roelofs, W. L.
    New York State Agricultural Experiment Station, USA.
    Unelius, C. Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Trimble, R. M.
    Southern Crop Protection and Food Research Centre, Canada.
    Geographic variation in pheromone chemistry, antennal electrophysiology, and pheromone-mediated trap catch of North American populations of the obliquebanded leafroller2003In: Environmental Entomology, ISSN 0046-225X, E-ISSN 1938-2936, Vol. 32, no 3, p. 470-476Article in journal (Refereed)
    Abstract [en]

    The total and relative amounts of (Z)-11-tetradecenyl acetate (Z11-14:Ac), (E)-11-tetradecenyl acetate (E11-14:Ac), (Z)-11-tetradecen-1-ol (Z11-14:OH) and (Z)-11-tetradecenal (Z11-14:Al), and the EAG response of male antennae to these pheromone gland compounds were compared in laboratory reared Choristoneura rosaceana Harris (Lepidoptera: Tortricidae) from British Columbia, Michigan, Ontario, New York, and Quebec. A field trapping experiment was conducted in each of these locations to determine the effect of Z11-14:Al on the numbers of moths captured. The amount of each of the four pheromone-gland compounds declined successively in moths from British Columbia, Quebec, Ontario, Michigan, and New York. The relative amount of Z11-14:Ac was greatest in moths from New York and smallest in moths from Ontario, whereas the relative amount of E11-14:Ac was greatest in moths from Ontario and smallest in moths from British Columbia. Moths from Ontario, Quebec, British Columbia, Michigan, and New York contained decreasing relative amounts of Z11-14:OH and Z11-14:Al. There was a trend of increasing antenna] sensitivity to each of the four pheromone-gland compounds in moths from New York, Michigan, Ontario, Quebec, and British Columbia. The addition of 1% Z11:Al to a three compound blend of Z11-14:Ac, E11-14:Ac and Z11-14:OH (97:2:1) resulted in a >twofold increase in average trap catch in British Columbia, Ontario, and Quebec; this compound had no effect on trap catch in Michigan or New York.

  • 25. El-Sayed, A M
    et al.
    Wainman, L I
    Santangelo, E M
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Trimble, R M
    Sex pheromone of a North American population of the spotted tentiform leafminer, Phyllonorycter blancardella2005In: Entomologia experimentalis et applicata, Vol. 116 (2), p. 143-148Article in journal (Refereed)
  • 26.
    El-Sayed, A.
    et al.
    SLU, Sweden.
    Unelius, C. Rikard
    KTH, Sweden.
    Liblikas, I.
    KTH, Sweden.
    Lofqvist, J.
    SLU, Sweden.
    Bengtsson, M.
    SLU, Sweden.
    Witzgall, P.
    SLU, Sweden.
    Effect of codlemone isomers on codling moth (Lepidoptera: Tortricidae) male attraction1998In: Environmental Entomology, ISSN 0046-225X, E-ISSN 1938-2936, Vol. 27, no 5, p. 1250-1254Article in journal (Refereed)
    Abstract [en]

    We studied the effect of codlemone geometric isomers (E,Z)-, (Z,E)-, and (Z,Z)-8,10-dodecadienol on sex attraction of male codling moth, Cydia pomonella (L.), in the field and in a wind tunnel. The use of an ultrasound evaporator made it possible to apply known rates of compound at defined isomeric purity. In the wind tunnel, 5, 20, and 100% addition of Z,E isomer to (E,E) -8,10-dodecadienol (codlemone) slightly increased male night response. However, field captures with these blends were not significantly different from codlemone alone. A 20 and 100% addition of E,Z isomer decreased male landings on the odor source in the wind tunnel and trap captures in the field; Z,Z had an antagonistic effect at 100%. The equilibrium isomer blend (100% EB; 26% E,Z; 20% Z,E; 5% Z,Z) strongly reduced male attraction. The behavioral effect of isomerization of codlemone in dispenser materials used for mating disruption has to be taken into consideration.

  • 27. El-Sayed, A.M.
    et al.
    Wainman, L.I.
    Santangelo, E.M.
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Trimble, R.M.
    Relative Attractiveness of (10E)-Dodecenyl Acetate and (4E,10E)-Dodecadienyl Acetate to Male Spotted Tentiform Leafminers Phyllonorycter blancardella (F.),2004In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 30, no 9, p. 1827-38Article in journal (Refereed)
  • 28.
    El-Sayed, Ashraf M.
    et al.
    New Zealand Inst Plant & Food Res Ltd, New Zealand.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. New Zealand Inst Plant & Food Res Ltd, New Zealand.
    Suckling, David M.
    New Zealand Inst Plant & Food Res Ltd, New Zealand;Univ Auckland, New Zealand.
    Honey Norisoprenoids Attract Bumble Bee, Bombus terrestris, in New Zealand Mountain Beech Forests2018In: Journal of Agricultural and Food Chemistry, ISSN 0021-8561, E-ISSN 1520-5118, Vol. 66, no 50, p. 13065-13072Article in journal (Refereed)
    Abstract [en]

    Three varieties of honey of different dominant floral origin were found to attract social Hymenoptera, including the large earth bumble bee, Bombus terrestris, in a New Zealand mountain beech forest. This study was undertaken to identify volatile organic compounds that induce the attraction of bumble bees to honeybee (Apis mellifera) honey. We analyzed the chemical composition of the volatile organic compounds produced in three distinct varieties of honey (i.e., manuka, honeydew, and clover honey). The composition of the chemical profile of the three honey varieties differed in the quality and in the ratio of compounds in the headspace. o-Methoxyacetophenone was the main compound in the headspace of all three honey varieties. Among the 40 compounds identified in the headspace in the three varieties, only seven shared compounds (i.e., benzaldehyde, benzyl alcohol, phenylacetaldehyde, 2-phenylethanol, isophorone, 4-oxoisophorone, and o-methoxyacetophenone) were present in the headspace of the three honey varieties. The relative attractiveness of various blends of the seven common compounds found in the three honey varieties was tested for the attraction to bumble bees in a mountain beech forest. A binary blend of isophorone and 4-oxoisophorone at a ratio of 90:10 was the most attractive blend for both bumble bee workers and queens. A small number of honey bee workers were also attracted to the former binary blend. Our study represents the first identification of a honey-derived attractant for bumble bees and honey bees. The potential application of our finding for monitoring of bumble bees or to enhance crop pollination and help to tackle the current concern of a global pollination crisis is discussed.

  • 29. El-Sayed, Ashraf
    et al.
    Manning, Lee-Anne
    Unelius, C. Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Park, Kye-Chung
    Stringer, Lloyd
    White, Nicola
    Bunn, Barry
    Twidle, Andrew
    Suckling, Max
    Attraction and Antennal Response of the Common Wasp, Vespula vulgaris (L.), to Selected Synthetic Chemicals in New Zealand Beech Forests2009In: Pest Management Science, ISSN 1526-498X, E-ISSN 1526-4998, Vol. 65, no 9, p. 975-981Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native birds and invertebrate biodiversity. This work was undertaken to develop synthetic attractants for these species to enable more efficient monitoring and management. RESULTS: Seven known wasp attractants (acetic acid, butyl butyrate, isobutanol, heptyl butyrate, octyl butyrate and 2,4-hexadienyl butyrate) were field tested, and only heptyl butyrate and octyl butyrate attracted significantly higher numbers of wasps than a non-baited trap. Accordingly, a series of straight-chain esters from methyl to decyl butyrate were prepared and field tested for attraction of social wasps. Peak biological activity occurred with hexyl butyrate, heptyl butyrate, octyl butyrate and nonyl butyrate. Polyethylene bags emitting approximately 18.4-22.6 mg day(-1) of heptyl butyrate were more attractive than polyethylene bags emitting approximately 14.7-16.8 mg day(-1) of heptyl butyrate in the field. Electroantennogram (EAG) studies indicated that queens and workers of V. vulgaris had olfactory receptor neurons responding to various aliphatic butyrates. CONCLUSION: These results are the first to be reported on the EAG response and the attraction of social wasps to synthetic chemicals in New Zealand beech forests and will enable monitoring of social wasp activity in beech forests. (C) 2009 Society of Chemical industry

  • 30. El-Sayed, Ashraf
    et al.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Twidle, Andrew
    Mitchell, Vanessa
    Manning, Lee-Anne
    Cole, Lyn
    Suckling, David M
    Flores, Fernanda M
    Zaviezo, Tania
    Bergmann, Jan
    Chrysanthemyl 2-acetoxy-3-methylbutanoate: the sex pheromone of the citrophilous mealybug Pseudococcus calceolariae2010In: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 51, no 7, p. 1075-1078Article in journal (Refereed)
    Abstract [en]

    Headspace volatiles collected from virgin females of the citrophilous mealybug, Pseudococcus calceolariae, contain three Compounds not present in the headspace of control samples. The main female-specific compound is identified as[2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl]methyl 2-acetoxy-3-methylbutanoate (chrysanthemyl 2-acetoxy-3-methylbutanoate). The other two compounds are identified as [2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl]methanol (chrysanthemol) and [2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl]methyl 2-hydroxy-3-methylbutanoate (chrysanthemyl 2-hydroxy-3-methylbutanoate). Traps baited with 100 mu g and 1000 mu g of chrysanthemyl 2-acetoxy-3-methylbutanoate captured 4- and 20-fold more males than traps baited with virgin females.

  • 31.
    Franco, Thiago A.
    et al.
    Univ Fed Rio de Janeiro, Brazil;Univ Calif Davis, USA.
    Xu, Pingxi
    Univ Calif Davis, USA.
    Brito, Nathalia F.
    Univ Fed Rio de Janeiro, Brazil.
    Oliveira, Daniele S.
    Univ Fed Rio de Janeiro, Brazil.
    Wen, Xiaolan
    Univ Calif Davis, USA.
    Moreira, Monica F.
    Univ Fed Rio de Janeiro, Brazil;Inst Nacl Ciencia & Tecnol Entomol Mol, Brazil.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Leal, Walter S.
    Univ Calif Davis, USA.
    Melo, Ana C. A.
    Univ Fed Rio de Janeiro, Brazil;Univ Calif Davis, USA;Inst Nacl Ciencia & Tecnol Entomol Mol, Brazil.
    Reverse chemical ecology-based approach leading to the accidental discovery of repellents for Rhodnius prolixus, a vector of Chagas diseases refractory to DEET2018In: Insect Biochemistry and Molecular Biology, ISSN 0965-1748, E-ISSN 1879-0240, Vol. 103, p. 46-52Article in journal (Refereed)
    Abstract [en]

    Rhodnius prolixus is one of the most important vectors of Chagas disease in Central and South America for which repellents and attractants are sorely needed. Repellents like DEET, picaridin, and IR3535 are widely used as the first line of defense against mosquitoes and other vectors, but they are ineffective against R. prolixus. Our initial goal was to identify in R. prolixus genome odorant receptors sensitive to putative sex pheromones. We compared gene expression of 21 ORs in the R. prolixus genome, identified 4 ORs enriched in male (compared with female) antennae. Attempts to de-orphanize these ORs using the Xenopus oocyte recording system showed that none of them responded to putative sex pheromone constituents. One of the them, RproOR80, was sensitive to 4 compounds in our panel of 109 odorants, namely, 2-heptanone, gamma-octalactone, acetophenone, and 4-methylcychohexanol. Interestingly, these compounds, particularly 4-methylcyclohexanol, showed strong repellency activity as indicated not only by a significant decrease in residence time close to a host, but also by a remarkable reduction in blood intake. 4-Methylcyclohexanol-elicited repellency activity was abolished in RNAi-treated insects. In summary, our search for pheromone receptors led to the discovery of repellents for R. prolixus.

  • 32. Gibb, A.R.
    et al.
    Suckling, D.M.
    El-Sayed, A.M.
    Bohman, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Dymock, J.J
    Larsen, M.L.
    Willoughby, B.E.
    (Z,E)-11,13-Hexadecadienyl Acetate: Sex Pheromone of the Grass Webworm Herpetogramma licarsisalis - Identification, Synthesis and Field Bioassays.2007In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 33, no 4, p. 839-47Article in journal (Refereed)
  • 33.
    Harper, Aimee R.
    et al.
    New Zealand Inst Plant & Food Res Ltd, New Zealand.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. New Zealand Inst Plant & Food Res Ltd, New Zealand.
    Townsend, Richard J.
    AgResearch Ltd, Lincoln Res Ctr, New Zealand.
    Suckling, David Maxwell
    New Zealand Inst Plant & Food Res Ltd, New Zealand.
    Dose reduction and alternatives to the phenol pheromone in monitoring and management of the grass grub Costelytra zealandica2017In: Pest Management Science, ISSN 1526-498X, E-ISSN 1526-4998, Vol. 73, no 11, p. 2252-2258Article in journal (Refereed)
    Abstract [en]

    BACKGROUNDEndemic New Zealand grass grub Costelytra zealandica is a pest of introduced pasture that uses phenol as a sex pheromone. The pheromone could be used to monitor and manage grass grub populations, but the irritating properties and toxicity of phenol for human handlers, as well as the possible ecotoxicological effects, pose obstacles to the deployment of the pheromone. This study aimed to limit the use of phenol by dose-response studies and investigation into alternative attractants and synergists to phenol. RESULTSNo difference in trap catch was seen across the range of 1-100mg of phenol, while rates below this (0.001-0.1mg) caused a large drop in catches. Our results indicated that 1mg loading in lures was enough to indicate beetle presence over 1 week. 4-Hydroxybenzaldehyde and p-cresol proved unattractive in this study, both as single attractants and as synergists with phenol. Phenyl acetate, phenyl benzoate and diphenyl carbonate all formed phenol under hydrolytic conditions to act as successful propheromones, while phenyl acetate was found to be as attractive as phenol on its own. CONCLUSIONThis study described several ways to reduce or avoid the use of phenol in the field while maintaining lure effectiveness. (c) 2017 Society of Chemical Industry

  • 34. Kalinova, B.
    et al.
    Hoskovec, M.
    Liblikas, I.
    KTH, Sweden.
    Unelius, C. Rikard
    Hansson, B. S.
    SLU, Sweden.
    Detection of sex pheromone components in Manduca sexta (L.)2001In: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 26, no 9, p. 1175-1186Article in journal (Refereed)
    Abstract [en]

    The ability of olfactory receptor neurons to detect female-produced sex pheromone components and a limited sample of potential host plant odours was studied by single-sensillum recordings from olfactory sensilla present on male and female antennae in Manduca sexta, The majority of pheromone-sensitive receptor neurons examined in males was specialized for detection of the two major pheromone components, E10,Z12-hexadecadienal and E10,E12,Z14-hexadecatrienal or E10,E12,E14-hexadecatrienal. New olfactory receptor neurons tuned to the minor components E10,E12-hexadecadienal and Z11-hexadecenal were found. in females, olfactory receptor neurons specific to Z11-hexadecanal were discovered. Pheromone components and host volatiles were detected by separate sets of receptor neurons.

  • 35. Karlson, J.
    et al.
    Borg Karlson, A. K.
    KTH, Sweden.
    Unelius, R.
    KTH, Sweden.
    Shoshan, M. C.
    Wilking, N.
    Ringborg, U.
    Linder, S.
    Inhibition of tumor cell growth by monoterpenes in vitro: Evidence of a Ras-independent mechanism of action1996In: Anti-Cancer Drugs, ISSN 0959-4973, E-ISSN 1473-5741, Vol. 7, no 4, p. 422-429Article in journal (Refereed)
    Abstract [en]

    (+)-Limonene (d-limonene) and related monoterpenes show chemopreventive activity against rodent mammary carcinoma and inhibit the growth of cancer cells in vitro, One suggested mechanism for the anti-tumorigenic effect of (+)-limonene is inhibition of the post-translational isoprenylation of growth controlling Pas oncoproteins. We have here examined the growth inhibitory effects of (+)-limonene and other related monoterpenes on PANC-1 pancreas carcinoma cells (carrying a K-ras mutation) and on 12V-H-ras-transformed rat fibroblasts, (+)- and (-)-perillyl alcohol, 7-methyl-perillyl alcohol, (+)-limonene oxide and (+)-perillic acid methyl ester were all found to efficiently inhibit cell growth at 1 mM, whereas (+)-limonene caused an approximately 50% growth reduction at 5 mM, Whereas BZA-BB, an inhibitor of Ras farnesyl transferase, was found to induce morphological reversion of 12v-H-ras-transformed cells, (+)-perillyl alcohol and (+)-limonene did not induce reversion. Furthermore, monoterpenes did not decrease MAP kinase enzyme activity or collagenase promoter activity in PANC-1 cells, two functions known to be down-stream from Pas, We conclude that although effective in inhibiting the growth of tumor cells harboring activated res oncogenes, limonene and (+)-perillyl alcohol are unlikely to act by inhibiting Ras function.

  • 36.
    Kleiber, Joseph R.
    et al.
    Oregon State University.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. The New Zealand Institute for Plant & Food Research Ltd., PB 4704, Christchurch, 8140, New Zealand.
    Lee, Jana
    USDAÐARS, Horticulture Crops Research Unit, Corvallis, OR 97331.
    Maxwell Suckling, David
    The New Zealand Institute for Plant & Food Research Ltd., PB 4704, Christchurch, 8140, New Zealand.
    Qian, Michael
    Oregon State University, Food Science and Technology, Corvallis, OR 97331.
    Bruck, Denny J.
    DuPont Pioneer, 7300 NW 62nd Ave., PO Box 1004, Johnston, IA 50131.
    Attractiveness of Fermentation and Related Products to Spotted Wing Drosophila (Diptera: Drosophilidae)2014In: Environmental Entomology, ISSN 0046-225X, E-ISSN 1938-2936, Vol. 43, no 2, p. 439-447Article in journal (Refereed)
    Abstract [en]

    Laboratory screening bioassays and field trapping experiments of spotted wing drosophila flies, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), were conducted to determine the attractiveness of 17 compounds as well as to compare attractant efficiency during peak fruit ripeness and postharvest captures late in the season. Compounds structurally related to each of the fermentation products acetic acid, ethanol, ethyl acetate, and 2-phenethyl alcohol were screened for attractiveness compared with a soap water control in greenhouse cage bioassays. The compounds determined to be attractive in the greenhouse bioassay (methanol, ethanol, propanol, formic acid, acetic acid, ethyl acetate, propyl acetate, phenethyl acetate, phenethyl propionate, and phenethyl butyrate) were individually tested in the field added to apple cider vinegar (ACV). The acids were also tested individually in neutralized AVC (NACV; pH 7). Combinations of the compounds were tested in NACV. The capture numbers in ACV traps were not significantly increased by the addition of any of the compounds tested, although significant deterrent effects of some of the compoundsallowed differences between treatments to be observed. Compounds that are most prevalent in wine and vinegar (methanol, ethanol, acetic acid, and ethyl acetate) as well as phenethyl propionate and phenethyl butyrate were less deterrent than the other compounds tested in the field. Captures during peak fruit ripeness were compared with the postharvest period when fruit hosts were not available or were overripe. Although the total number of flies captured late in the season was lower, the trends in treatment performance were similar, indicating a consistent performance of these baits from peak fruit ripeness through postharvest.

  • 37.
    Lanne, B. S.
    et al.
    Gothenburg University.
    Schlyter, F.
    SLU, Alnarp.
    Byers, J. A.
    SLU, Alnarp.
    Lofqvist, J.
    SLU, Alnarp.
    Leufven, A.
    Gothenburg University.
    Bergstrom, G.
    Gothenburg University.
    Vanderpers, J. N. C.
    Unelius, C. Rikard
    KTH, Stockholm.
    Baeckstrom, P.
    KTH, Stockholm.
    Norin, T.
    KTH, Stockholm.
    Differences in Attraction to Semiochemicals Present in Sympatric Pine Shoot Beetles, (Coleoptera, Scolytidae) Tomicus minor and Tomicus piniperda1987In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 13, no 5, p. 1045-1067Article in journal (Refereed)
  • 38. Legrand, S.
    et al.
    Nordlander, G.
    SLU, Sweden.
    Nordenhem, H.
    SLU, Sweden.
    Borg-Karlson, A. K.
    KTH, Sweden.
    Unelius, C. Rikard
    Hydroxy-methoxybenzoic methyl esters: Synthesis and antifeedant activity on the pine weevil, Hylobius abietis2004In: Zeitschrift für Naturforschung. B, A journal of chemical sciences, ISSN 0932-0776, E-ISSN 1865-7117, Vol. 59, no 7, p. 829-835Article in journal (Refereed)
    Abstract [en]

    The pine weevil Hylobius abietis (L.) (Coleoptera: Curculionidae) feeds on the bark of coniferous seedlings and is the economically most important forestry restocking pest in large parts of Europe. Substances with an antifeedant effect may offer an environmentally friendly alternative to insecticides for the protection of planted seedlings. Bioassays were performed on commercial and synthetic methyl hydroxy-methoxybenzoates in order to determine their possible antifeedant activity. Two methyl hydroxy-methoxybenzoates were synthesized by esterification and mono-O-methylation of two dihydroxybenzoic acids. A regioselective protection-deprotection strategy was used in the synthetic pathway of the other non-commercial esters, esterification and selective pivaloylation of the less-hindered hydroxyl group of other commercial dihydroxybenzoic acids gave diester intermediates, which then were O-methylated before methanolysis of the pivaloyl group which yielded the desired non-commercial methyl hydroxy-methoxybenzoates. The five synthesized methyl hydroxy-methoxybenzoic esters were complemented with commercial samples of the five other isomers of methyl hydroxy-methoxybenzoate and spectrometric data were collected for the complete set of isomers. All ten isomers were tested for their antifeedant effect on the pine weevil. The effect varied considerably among the hydroxy-methoxybenzoic esters. Methyl 2-hydroxy-3-methoxybenzoate showed the highest effect and may thus be a candidate for practical use in pine weevil pest management.

  • 39.
    Legrand, Sacha
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Botton, Marcos
    Coracini, Miryan
    Witzgall, Peter
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Synthesis and Field Test of Sex Pheromone Components of the Leafroller Argyrotaenia sphaleropa.2004In: Zeit. f. Naturforsch. C, Vol. 59c, no 9/10, p. 708-712Article in journal (Refereed)
  • 40. Legrand, Sacha
    et al.
    Heikkinen, Harri
    Nicholls, Ian A.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Root, Andrew
    Svenson, Johan
    Unelius, C. Rikard
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Preparation, characterization and application of a stationary chromatographic phase from a new (+)-tartaric acid derivative2010In: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 51, no 17, p. 2258-2261Article in journal (Refereed)
    Abstract [en]

    The preparation, characterization and application of a new stationary phase derived from 1,4-cyclohexanedione and diethyl (+)-tartrate are described. A suitable TADDOL for immobilization has been synthesized and grafted to a gamma-mercaptopropylsilylated silica gel. The resulting modified stationary phase has been characterized and its ability to separate enantiomers has been studied. While the free TADDOL in solution was able to resolve a range of enantiomers, the resolving properties were lost on immobilization. Solid state C-13 CPMAS NMR of the new stationary phase was used to explain the lack of stereoselective recognition. (C) 2010 Elsevier Ltd. All rights reserved.

  • 41.
    Legrand, Sacha
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Luukinen, Hannu
    Isaksson, Roland
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Kilpelainen, I
    Lindström, Mikael
    Nicholls, Ian Alan
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Synthesis, NMR conformational studies and host-guest behaviour of new (+)-tartaric acid derivatives2005In: Tetrahedron: Asymmetry, Vol. 16, no 3, p. 635-640Article in journal (Refereed)
  • 42. Liblikas, I
    et al.
    Santangelo, E M
    Sandell, J
    Baeckström, P
    Svensson, M
    Jacobsson, U
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Simplified isolation procedure and interconversion of the diastereomers of nepetalactone and nepetalactol2005In: Journal of natural products, Vol. 68 (6), p. 886-890Article in journal (Refereed)
  • 43. Liotta, F.
    et al.
    Unelius, C. R.
    KTH, Sweden.
    Kozak, J.
    Norin, T.
    KTH, Sweden.
    Synthesis of Carbocyclic Nucleoside Analogs by Palladium-Mediated Coupling1992In: Acta Chemica Scandinavica, ISSN 0904-213X, E-ISSN 1902-3103, Vol. 46, no 7, p. 686-688Article in journal (Refereed)
  • 44. Manrique, G.
    et al.
    Vitta, A.C.R.
    Ferreira, R.A.
    Zani, C.L
    Unelius, Rikard
    Lazzari, C.R.
    Diotaiuti, L.
    Lorenzo, M.G.
    Chemical Communication in Chagas Disease Vectors. Source, Identity and Potential Function of Volatiles Released by the Metasternal and Brindleys Glands of Triatoma infestans Adults.2006In: J. Chem. Ecol., Vol. 32, no 9, p. 2035-2052Article in journal (Refereed)
  • 45.
    Marshall, D. G.
    et al.
    AgResearch Ltd, New Zealand.
    Jackson, T. A.
    AgResearch Ltd, New Zealand.
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. New Zealand Inst Plant & Food Res Ltd, New Zealand.
    Wee, S. L.
    New Zealand Inst Plant & Food Res Ltd, New Zealand ; Univ Kebangsaan Malaysia, Malaysia.
    Young, S. D.
    AgResearch Ltd, New Zealand.
    Townsend, R. J.
    AgResearch Ltd, New Zealand.
    Suckling, D. M.
    New Zealand Inst Plant & Food Res Ltd, New Zealand ; Univ Auckland, New Zealand.
    Morganella morganii bacteria produces phenol as the sex pheromone of the New Zealand grass grub from tyrosine in the colleterial gland2016In: The Science of Nature: Naturwissenschaften, ISSN 0028-1042, E-ISSN 1432-1904, Vol. 103, no 7-8, article id 59Article in journal (Refereed)
    Abstract [en]

    Costelytra zealandica (Coleoptera: Scarabeidae) is a univoltine endemic species that has colonised and become a major pest of introduced clover and ryegrass pastures that form about half of the land area of New Zealand. Female beetles were previously shown to use phenol as their sex pheromone produced by symbiotic bacteria in the accessory or colleterial gland. In this study, production of phenol was confirmed from the female beetles, while bacteria were isolated from the gland and tested for attractiveness towards grass grub males in traps in the field. The phenol-producing bacterial taxon was identified by partial sequencing of the 16SrRNA gene, as Morganella morganii. We then tested the hypothesis that the phenol sex pheromone is biosynthesized from the amino acid tyrosine by the bacteria. This was shown to be correct, by addition of isotopically labelled tyrosine (C-13) to the bacterial broth, followed by detection of the labelled phenol by SPME-GCMS. Elucidation of this pathway provides specific evidence how the phenol is produced as an insect sex pheromone by a mutualistic bacteria.

  • 46.
    Mattson, A.
    et al.
    KTH, Sweden.
    Orrenius, C.
    KTH, Sweden.
    Ohrner, N.
    KTH, Sweden.
    Unelius, C. R.
    Hult, K.
    KTH, Sweden.
    Norin, T.
    KTH, Sweden.
    Kinetic resolution of chiral auxiliaries with C-2-symmetry by lipase-catalyzed alcoholysis and aminolysis1996In: Acta Chemica Scandinavica, ISSN 0904-213X, E-ISSN 1902-3103, Vol. 50, no 10, p. 918-921Article in journal (Refereed)
    Abstract [en]

    Three cyclic diols, 1,2-cyclohexanediol (1), 1,3-cyclohexanediol (2), and 1,3-cyclopentanediol (3), two acyclic unsaturated diols, 1,5-hexadiene-3,4-diol (4) and 1,7-octadiyne-3,6-diol (5), and a cyclic diamine, 1,2-cyclohexanediamine (6), have been kinetically resolved in alcoholysis and aminolysis reactions, catalyzed by Candida antarctica component B lipase, using S-ethyl thiooctanoate or ethyl octanoate as acyl donors. Acceptable stereoselectivity was achieved in most cases.

  • 47.
    Mozuraitis, R.
    et al.
    KTH, Sweden.
    Buda, V.
    Liblikas, I.
    KTH, Sweden.
    Unelius, C. Rikard
    Borg-Karlson, A. K.
    KTH, Sweden.
    Parthenogenesis, calling behavior, and insect-released volatiles of leafminer moth Phyllonorycter emberizaepenella2002In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 28, no 6, p. 1191-1208Article in journal (Refereed)
    Abstract [en]

    We proved that the leafminer moth Phyllonorycter emberizaepenella (Lepidoptera: Gracillariidae) reproduces by parthenogenesis of the thelytoky type. Despite a complete absence of males, parthenogenetically reproducing females diurnally demonstrated the calling posture normally used for releasing signaling compounds. Two compounds, which we collected from a calling female, were identified as potential sex pheromone components: (8E,10E)-8,10-tetradecadienyl acetate and (8E,10E)-8,10-tetradecadienol, the latter occurring only in trace amounts. In field experiments, no males were attracted to traps baited with either the potential sex pheromone or with virgin females. Both the pattern of behavior and the chemical characteristics of the pheromone of Ph. emberizaepenella species were similar to those known for Lepidoptera with the usual amphimictic mode of reproduction. Theoretical speculations that in thelytoky, where there is no need to find a sexual partner, the individuals would obtain certain advantages due to reduction in their sexual behavior, were, thus, not confirmed for Ph. emberizaepenella.

  • 48.
    Norin, T.
    et al.
    KTH, Sweden.
    Unelius, C. Rikard
    KTH, Sweden.
    Selectivity in Diimide Reductions of Conjugated Enynes1990In: Acta Chemica Scandinavica, ISSN 0904-213X, E-ISSN 1902-3103, Vol. 44, no 1, p. 106-107Article in journal (Refereed)
  • 49. Park, Kye Chung
    et al.
    McNeill, Mark
    Unelius, C. Rikard
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Oh, Hyun-Woo
    Suckling, David M.
    Characterization of olfactory receptor neurons for pheromone candidate and plant volatile compounds in the clover root weevil, Sitona lepidus2013In: Journal of insect physiology, ISSN 0022-1910, E-ISSN 1879-1611, Vol. 59, no 12, p. 1222-1234Article in journal (Refereed)
    Abstract [en]

    Antennal olfactory receptor neurons (ORNs) for pheromone and plant volatile compounds were identified and characterized in male and female clover root weevil, Sitona lepidus (Gyllenhal), using the single sensillum recording technique with five pheromone-related compounds, and 40 host and non-host plant volatile compounds. Overall, seven different types of olfactory sensilla containing specialized ORNs were identified in each sex of S. lepidus. Among them, three different types of sensilla in the males and two types in the females housed ORNs specialized for pheromone-related compounds. The ORNs in males were specialized for 4-methyl-3,5-heptanedione or one or more of four stereoisomers of 5-hydroxy-4-methyl-3-heptanone. In contrast, female sensilla did not contain ORNs sensitive to 4-methyl-3,5-heptanedione while they contained ORNs sensitive to and specialized for the stereoisomers of (4S,5S)-5-hydroxy-4-methyl-3-heptanone. In addition to the pheromone-related ORNs, four types of olfactory sensilla contained ORNs responsive to plant volatile compounds in male S. lepidus, and five types in females. Most of the ORNs identified in S. lepidus showed a high degree of specificity to specific volatile compounds although some of the active compounds showed overlapping response spectra in the ORNs across different types of sensilla. The most active plant volatile compounds were the four green leaf volatile compounds, (E)-2-hexenol, (Z)-2-hexenol, (Z)-3-hexenol and (E)-2-hexenal, and isomers of two monoterpenols, (+/-)-linalool and (+/-)-alpha-terpineol, all eliciting strong responses from relatively large numbers of ORNs in male and female S. lepidus. Our study indicates that S. lepidus has a set of highly sensitive and selective ORNs for pheromone and plant volatile compounds. Further work is needed to elucidate the behavioral implications of these findings. (C) 2013 Elsevier Ltd. All rights reserved.

  • 50. Pettersson, Marie
    et al.
    Unelius, Rikard
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Valterova, I
    Borg-Karlson, A-K
    Semiochemicals related to the aphid Cinara pilicornis and its host, Picea abies: A method to assign nepetalactone diastereomers2008In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1180, no 1-2, p. 165-170Article in journal (Refereed)
12 1 - 50 of 83
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf