kth.sePublications
Change search
Refine search result
1234 1 - 50 of 157
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • 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. Adia, Madina Mohamed
    et al.
    Emami, Seyedeh Noushin
    Byamukama, Robert
    Faye, Ingrid
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Antiplasmodial activity and phytochemical analysis of extracts from selected Ugandan medicinal plants2016In: Journal of Ethnopharmacology, ISSN 0378-8741, E-ISSN 1872-7573, Vol. 186, p. 14-19Article in journal (Refereed)
    Abstract [en]

    Ethnopharmacological relevance: Resistance of the parasites to known antimalarial drugs has provided the necessity to find new drugs from natural products against malaria. The aim of the study was to evaluate the in vitro antiplasmodial activity of some plants used by Traditional Medical Practitioners (TMPs) of Prometra and Rukararwe in malaria treatment in Uganda to provide scientific proof of the efficacies claimed by these Herbalists. Materials and methods: The air dried samples of Clerodendrum rotundifolium (leaves), Microglossa pyrifolia (leaves), Momordica foetida (leaves) and Zanthoxylum chalybeum (stem bark) used for malaria treatment by TMPs were successively extracted with ethyl acetate, methanol and water to yield twelve extracts. The extracts were tested against the chloroquine-sensitive (NF54) and chloroquine-resistant (FCR3) Plasmodium falciparum strains in vitro using the micro Mark III test which is based on assessing the inhibition of schizont maturation. A compound A was extracted and purified from the stem bark of Z. chalybeum and its structure was identified and confirmed by spectroscopic methods. Results: Most of the extracts tested (92%) showed an antiplasmodial activity with IC50 < 50 mu g/mL. In spite of successive extractions with different solvents, potent anti-plasmodial activity (IC50 < 5 mu g/mL) was observed in the ethyl acetate, methanol and aqueous extracts of M. pyrifolia and C. rotundifolium. Preferential enrichments of activity into water (IC50 < 15 mu g/mL) and Ethyl acetate (IC50 < 5 mu g/mL) were seen in the case of M. foetida and Z chalybeum respectively. The most active extracts were from C rotundifolium and M. pyrifolia with IC50 values less than 2 mu g/mL. Phytochemical analysis of the extracts revealed the presence of saponins, tannins, flavonoids, alkaloids and cardiac glycocides. Fagaramide isolated from Z chalybeum had a higher activity (IC50 2.85 mu g/mL) against the chloroquine-resistant strain than against the chloroquine-senstive (IC50 16.6 mu g/mL) strain used in the study. Conclusion: The plant extracts analysed in this study presented an average antiplasmodial activity (58%). This study revealed for the first time the antiplasmodial activity of the plant C. rotundofolium. It's the first time the compound fagaramide (N-isobutyl-3-(3,4-methylene dioxyphenyl) - 2E-propenamide) has been isolated from Z. chalybeum as one of the compounds that contribute to the activity of this plant against P. falciparum.

  • 2. Albabtain, Reham
    et al.
    Azeem, Muhammad
    KTH, School of Chemical Science and Engineering (CHE), Chemistry. Karolinska Institutet, Sweden.
    Wondimu, Zenebech
    Lindberg, Tulay
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Gustafsson, Anders
    Investigations of a Possible Chemical Effect of Salvadora persica Chewing Sticks2017In: Evidence-based Complementary and Alternative Medicine, ISSN 1741-427X, E-ISSN 1741-4288, article id 2576548Article in journal (Refereed)
    Abstract [en]

    Salvadora persica is commonly used chewing sticks in many parts of the world as an oral hygiene tool. This study measured the amount of benzyl isothiocyanate (BITC) released into the mouth and assessed its retention time in saliva. The study also tested if the released amount of BITC could potentially be antibacterial or cytotoxic. Twelve subjects brushed their teeth with fresh Miswak once, twice, and four times. The amount of BITC in the saliva and in the used brushes was quantified using gas chromatography-mass spectrometry. The antibacterial effect of BITC and Miswak essential oil (MEO) was tested against Haemophilus influenzae, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis. The cytotoxic effect on gingival fibroblasts and keratinocytes was tested using MTT. The highest amount of the active compounds was detected in saliva after using the Miswak tip for once and immediately. It significantly decreased when the Miswak tip was used more than once and thus after 10 min. The growth of the tested bacteria was inhibited by MEO and BITC in a dose dependent manner, P. gingivalis being the most sensitive. MTT assay showed that BITC and MEO were cytotoxic towards gingival fibroblasts while oral keratinocytes showed resistance. This study suggests that the Miswak tip should be cut before each use to ensure the maximum effect.

  • 3.
    Almquist, Ann-Charlotte
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Fäldt, Jenny
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Yart, A.
    Chevet, Y.
    Sauvard, D.
    Lieutier, F.
    Borg-Karlson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Host selection in Tomicus piniperda L.: Composition of monoterpene hydrocarbons in relation to attack frequency in the shoot feeding phase2006In: Zeitschrift fur Naturforschung - Section C Journal of Biosciences, ISSN 0939-5075, Vol. 61, no 5-6, p. 439-444Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate the host selection capacity of the pine shoot beetle, Tomicus piniperda, in the shoot-feeding phase and analyze the chiral and non-chiral host volatiles by means of GC-MS and 2D-GC in five Pinus species originating from France (Pinus sylvestris, P. halepensis, P. nigra laricio, P. pinaster maritima, P. pinaster mesogeensis). Dominating monoterpenes were (-)-α-pinene, (+)-α-pinene, (-)-β-pinene and (+)-3-carene. The amounts of the enantiomers varied considerably within and among the species. In a principal component analysis-plot, based on the absolute amounts of 18 monoterpene hydrocarbons, separation of the pine species into two groups was obtained. P. halepensis and P. sylvestris were grouped according to the amount of (+)-α-pinene and (+)-3-carene, while P. nigra laricio, P. pinaster maritima and P. pinaster mesogeensis were grouped according to (-)-α-pinene and (-)-β-pinene. P. nigra laricio was the species most attacked and P. halepensis the one least attacked by T. piniperda.

  • 4. Andersson, J.
    et al.
    Borg-Karlson, Anna-Karin
    KTH, Superseded Departments (pre-2005), Chemistry.
    Wiklund, C.
    Antiaphrodisiacs in pierid butterflies: A theme with variation!2003In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 29, no 6, p. 1489-1499Article in journal (Refereed)
    Abstract [en]

    Male Pieris napi butterflies previously have been shown to synthesize and transfer an antiaphrodisiac, methyl salicylate (MeS), to females at mating. This substance curtails courtship and decreases the likelihood of female remating. Here, we show that similar systems occur in Pieris rapae and Pieris brassicae. In P. rapae, C-13-labeling studies showed that males utilize the amino acids phenylalanine and tryptophan as precursors to MeS and indole, respectively. These volatiles are transferred to females at mating and function as antiaphrodisiacs, as demonstrated by field tests entailing painting MeS, indole, or a mixture on the abdomens of virgin females and assessing their attractiveness to wild males. With P. brassicae, C-13-labeling studies showed that males use phenylalanine as a precursor to synthesize benzyl cyanide, which was demonstrated to function as an antiaphrodisiac by field tests similar to those for P. rapae. This communication system exhibits both similarities and differences among the three species; in P. napi and P. rapae, males are fragrant but transfer a volatile antiaphrodisiac to females that is completely different from the male odor, whereas in P. brassicae the antiaphrodisiac transferred by male to female is identical with male odor.

  • 5. Andersson, J.
    et al.
    Borg-Karlson, Anna-Karin
    KTH, Superseded Departments (pre-2005), Chemistry.
    Wiklund, C.
    Sexual cooperation and conflict in butterflies: a male-transferred anti-aphrodisiac reduces harassment of recently mated females2000In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 267, no 1450, p. 1271-1275Article in journal (Refereed)
    Abstract [en]

    Sexual selection theory predicts that the different selection pressures on males and females result in sexual conflict. However, in some instances males and females share a common interest which could lead to sexual cooperation. In the pierid butterfly Pieris napi the male and the recently mated female share a common interest in reducing female harassment by other males soon after mating. Here we show that P. napi males transfer an anti-aphrodisiac to the female at mating, methyl-salicylate (MeS), which is a volatile substance which mated females emit when courted and which makes males quickly abandon them. A C-13-labelling experiment demonstrated that only males synthesize MeS. The effect of this antiaphrodisiac is so strong that most males will refrain from mating with virgin females to whom MeS has been artificially applied. In P. napi, males also transfer nutrients to females at mating. This increases female fecundity and longevity and so females benefit from remating. Hence, sexual cooperation gradually turns to conflict. Future research is required to reveal which sex controls the gradual decrease in the MeS titre which is necessary for allowing mated females to regain attractiveness and remate.

  • 6. Andersson, Johan
    et al.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Vongvanich, Namphung
    Wiklund, Christer
    Male sex pheromone release and female mate choice in a butterfly2007In: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 210, no 6, p. 964-970Article in journal (Refereed)
    Abstract [en]

    In butterflies female mate choice is influenced by both visual and olfactory cues, the latter of which are important at close range. Males of the green-veined butterfly, Pieris napi, are known to release citral ( mixture of geranial and neral, 1: 1), but its role(s) and conditions of release are not known. Here, we show that male P. napi release citral when interacting with conspecific males, conspecific females, heterospecific males and also when alone. The amount of citral released correlated strongly with male flight activity, which explained more than 70% of the variation. This suggests that males do not exercise control over turning release on or off, but rather that citral is emitted as a passive physical process during flight. Electroantennogram experiments showed that female antennal response was ten times more sensitive to citral than male response. Females expressed acceptance behavior when exposed to models made with freshly excised male wings or those treated with citral following chemical extraction, but not to ones with extracted wings only. Hence, these behavioral and electrophysiological tests provide strong evidence that citral is a signal from the male directed to the female during courtship, and that it functions as a male sex pheromone.

  • 7.
    Andersson, Johan
    et al.
    KTH, Superseded Departments (pre-2005), Chemistry.
    Borg-Karlson, Anna-Karin
    KTH, Superseded Departments (pre-2005), Chemistry.
    Wiklund, C.
    Sexual conflict and anti-aphrodisiac titre in a polyandrous butterfly: male ejaculate tailoring and absence of female control2004In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 271, no 1550, p. 1765-1770Article in journal (Refereed)
    Abstract [en]

    Males of the green-veined butterfly Pieris napi synthesize and transfer the volatile methyl salicylate (MeS) to females at mating, a substance that is emitted by non-virgin females when courted by males, curtailing courtship and decreasing the likelihood of female re-mating. The volatile is released when females display the 'mate-refusal' posture with spread wings and elevated abdomen, when courted by conspecific males. Here, we assess how the amount of MeS released by courted females changes over time since mating, and whether it is influenced by the frequency with which females display the mate-refusal posture. We also assess whether males tailor the anti-aphrodisiac content of ejaculates with respect to the expected degree of sperm competition, by comparing how males allocate MeS proportionately to first and second ejaculates in relation to ejaculate mass. The results show that females housed for 5 days in individual cages where they were able to fly and oviposit normally, released similar amounts of MeS. However, females housed together for the same period of time, causing them to frequently display the mate-refusal posture, released significantly lower levels of MeS than the individually housed females. This indicates that female display of the mate-refusal posture depletes their anti-aphrodisiac stores, and suggests that females are unable to voluntarily control their release of the anti-aphrodisiac. A comparison of relative proportion of MeS transferred by males in their first and second ejaculates showed that proportionately more MeS was allocated to the first ejaculate, in accordance with the idea that these are tailored to delay female re-mating.

  • 8. Ansebo, L.
    et al.
    Coracini, M. D. A.
    Bengtsson, M.
    Liblikas, Ilme
    KTH, Superseded Departments (pre-2005), Chemistry.
    Ramirez, Martha
    KTH, Superseded Departments (pre-2005), Chemistry.
    Borg-Karlson, Anna-Karin
    KTH, Superseded Departments (pre-2005), Chemistry.
    Tasin, M.
    Witzgall, P.
    Antennal and behavioural response of codling moth Cydia pomonella to plant volatiles2004In: Journal of applied entomology, ISSN 0931-2048, E-ISSN 1439-0418, Vol. 128, no 7, p. 488-493Article in journal (Refereed)
    Abstract [en]

    Identification of host volatile compounds attractive to codling moth Cydia pomonella, a most important insect of apple, will contribute to the development of safe control techniques. Synthetic apple volatiles in two doses were tested for antennal and behavioural activity in codling moth. Female antennae strongly responded to (Z)3-hexenol, (Z)3-hexenyl benzoate, (Z)3-hexenyl hexanoate, (+/-)-linalool and E,E-alpha-farnesene. Two other compounds eliciting a strong antennal response were the pear ester, ethyl (E,Z)-2,4-decadienoate, and its corresponding aldehyde, E,E-2,4-decadienal, which is a component of the larval defence secretion of the European apple sawfly. Attraction of codling moth to compounds eliciting a strong antennal response was tested in a wind tunnel. Male moths were best attracted to a blend of (E,E)-alpha-farnesene, (E)-beta-farnesene and ethyl (E,Z)-2,4-decadienoate. The aldehyde E,E-2,4-decadienal had an antagonistic effect when added to the above mixture.

  • 9. Ashitani, T.
    et al.
    Kusumoto, N.
    Borg-Karlson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Fujita, K.
    Takahashi, K.
    Antitermite activity of β-caryophyllene epoxide and episulfide2013In: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 68 C, no 7-8, p. 302-306Article in journal (Refereed)
    Abstract [en]

    Caryophyllene-6,7-epoxide and caryophyllene-6,7-episulfide can be easily synthesized from β-caryophyllene by autoxidation or episulfidation. The bioactivities of β-caryophyllene and its derivatives were investigated against the subterranean termite Reticulitermes speratus Kolbe. The antifeedant, feeding, and termiticidal activities of each compound were tested using no-choice, dual-choice, and non-contact methods. Antitermitic activities were not shown by β-caryophyllene, but were observed for the oxide and sulfide derivatives. Caryophyllene- 6,7-episulfide showed especially high antifeedant and termiticidal activities. Thus, naturally abundant, non-bioactive β-caryophyllene can be easily converted into an antitermite reagent via a non-biological process.

  • 10. Ashitani, Tatsuya
    et al.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Fujita, Koki
    Nagahama, Shizuo
    Reaction mechanism of direct episulfidation of caryophyllene and humulene2008In: Natural Product Research, ISSN 1478-6419, E-ISSN 1478-6427, Vol. 22, no 6, p. 495-498Article in journal (Refereed)
    Abstract [en]

    Direct episulfidations of caryophyllene or humulene with elemental sulfur were examined by means of gas chromatography. Caryophyllene-6,7-episulfide was formed at an early stage in a reaction of the caryophyllene and elemental sulfur at 120C. Caryophyllene-3,6-sulfide and polymer compounds were formed after the episulfidation. Formations of the these compounds were related to the disappearance of the caryophyllene-6,7-episulfide. Isomerization from the caryophyllene to isocaryophyllene was also observed during the reaction. In the reaction of humulene with elemental sulfur, humulene-6,7-episulfide was initially produced and then converted to humulene-9,10-episulfide. It was assumed that the polymer compound in the reaction of humulene with sulfur was related to the disappearance of the both humulene episulfides.

  • 11.
    Ashitani, Tatsuya
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Yamagata University, Japan.
    Garboui, S. S.
    Schubert, Fredrik
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Vongsombath, Chanda
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. National University of Laos (NOUL), Laos.
    Liblikas, I.
    Pålsson, Katinka
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Institute of Technology, Estonia.
    Activity studies of sesquiterpene oxides and sulfides from the plant Hyptis suaveolens (Lamiaceae) and its repellency on Ixodes ricinus (Acari: Ixodidae)2015In: Experimental & applied acarology, ISSN 0168-8162, E-ISSN 1572-9702Article in journal (Refereed)
    Abstract [en]

    Hyptis suaveolens (Lamiaceae), a plant traditionally used as a mosquito repellent, has been investigated for repellent properties against nymphs of the tick Ixodesricinus. Essential oils and volatile compounds of fresh and dried leaves, from plants originating from Laos and Guinea-Bissau, were identified by GC–MS and tested in a tick repellency bioassay. All the essential oils were strongly repellent against the ticks, even though the main volatile constituents differed in their proportions of potentially tick repellent chemicals. (+)/(−)-sabinene were present in high amounts in all preparations, and dominated the emission from dry and fresh leaves together with 1,8-cineol and α-phellandrene. 1,8-Cineol and sabinene were major compounds in the essential oils from H. suaveolens from Laos. Main compounds in H. suaveolens from Guinea-Bissau were (−)-sabinene, limonene and terpinolene. Among the sesquiterpene hydrocarbons identified, α-humulene exhibited strong tick repellency (96.8 %). Structure activity studies of oxidation or sulfidation products of germacrene D, α-humulene and β-caryophyllene, showed increased tick repellent activity: of mint sulfide (59.4 %), humulene-6,7-oxide (94.5 %) and caryophyllene-6,7-oxide (96.9 %). The substitution of oxygen with sulfur slightly lowered the repellency. The effects of the constituents in the oils can then be regarded as a trade off between the subsequently lower volatility of the sesquiterpene derivatives compared to the monoterpenes and may thus increase their potential usefulness as tick repellents.

  • 12.
    Asiimwe, Savina
    et al.
    Makerere Univ, Sch Biosci, Kampala, Uganda.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Azeem, Muhammad
    Mugisha, Maud Kamatenesi
    Namutebi, Agnes
    Gakunga, Ndukui James
    Chemical composition and Toxicological evaluation of the aqueous leaf extracts of Plectranthus amboinicus Lour: Spreng2014In: International Journal of Pharmaceutical Science Invention, ISSN 2319-6718, Vol. 3, no 2, p. 19-27Article in journal (Refereed)
  • 13.
    Asiimwe, Savina
    et al.
    Makerere Univ, Sch Biosci, Kampala, Uganda.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Azeem, Muhammad
    Sofrata, Abier Hamed
    Byamukama, Robert
    Mugisha, Maud Kamatenesi
    Namutebi, Agnes
    Chemical composition and antimicrobial evaluation of the essential oil and fractions obtained from Plectranthus amboinicus(Lour.): Spreng traditionally used in the management of HIV/AIDS opportunistic infectionsManuscript (preprint) (Other academic)
  • 14.
    Asiimwe, Savina
    et al.
    Makerere Univ, Sch Biosci, Kampala, Uganda.
    Kamatenesi-Mugisha, Maud
    Namutebi, Agnes
    Borg-Karlsson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Musiimenta, Peace
    Ethnobotanical study of nutri-medicinal plants used for the management of HIV/AIDS opportunistic ailments among the local communities of western Uganda2013In: Journal of Ethnopharmacology, ISSN 0378-8741, E-ISSN 1872-7573, Vol. 150, no 2, p. 639-648Article in journal (Refereed)
    Abstract [en]

    Ethnopharmacological relevance: Herbal remedies are a source of therapeutics for nearly 80% of the population in Uganda. Poor health facilities and limited access to antiretroviral drugs have perpetuated and increased the use of traditional medicine especially in rural areas for the treatment of opportunistic ailments of HIV/AIDS. To document the traditional uses of nutri-medicinal plants in the management of immunocompromised ailments associated with HIV/AIDS. To document the parts and growth forms of plants used, methods of preparation and administration of the herbal remedies. Materials and methods: The study was conducted in Mbarara and Isingiro districts of western Uganda between December 2010 and May 2011. Ethnobotanical information was collected from 64 respondents who were sampled based on recommendations of local elders and administrators. Ethnobotanical data on the use of nutri-medicinal plants for traditional treatment of HIV/AIDS opportunistic ailments were collected by employing semi-structured interviews with selected respondents, house hold visits and field observations as described by (Martin, 1995a). The respondents were mainly traditional medical practitioners who treat patients who are already receiving antiretroviral drugs. Fidelity levels of plant species and informant consensus factor were determined to show the percentage of informants claiming the use of certain plant species for the same major purpose and to analyse people's knowledge of plant use. Results: The study revealed 81 plant species most of which were herbs (49%). Leaves (71%) were the most frequently used parts in remedy preparations which were mainly administered orally (85%). The majority of plants (54%) were harvested from wild populations. Hibiscus sabdariffa L, Plumeria obtusa L, and Abutilon guineense (Shumach.) Baker. F and Exell were the nutri-medicinal plants that scored the highest Fidelity level values. The informant's consensus about usages of plants ranged from 0.75 to 0.80. Plants that are presumed to be effective in treating a certain disease have higher informant consensus factor (ICF) values. Family Asteraceae accounted for 18% of the total species recorded. Thirteen species (16%) of the plants are edible and provide nutritional support. Conclusion: The study recorded plant species with potential to treat ailments associated with immunocompromised people living with HIV/AIDS in western Uganda. Such studies can help stimulate confidence in traditional medicine and enhance appreciation of herbal medicine among the people and to appreciate the value of the plant resources and therefore enhance conservation efforts of the plant species. The high consensus means the majority of informants agree on the use of plant species and this reflects the intercultural relevance and the agreement in the use of the nutri-medicinal plants to the people. We recommend the documented plants for further Ethnopharmacological studies.

  • 15.
    Asiimwe, Savina
    et al.
    Makerere Univ, Sch Biosci, Kampala, Uganda.
    Namutebi, Agnes
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Mugisha, Maud Kamatenesi
    Kakudidi, Esezah Kyomugisha
    Hannington, Ortem-Origa
    Documentation and consensus of indigenous knowledge on medicinal plants used by the local communities of western Uganda2014In: Journal of Natural Product and Plant Resource, ISSN 2231-3184, Vol. 4, no 1, p. 34-42Article in journal (Refereed)
    Abstract [en]

    An ethnobotanical study was conducted to document the uses of medicinal plants among the local communities of western Uganda. The aim of the study was to identify and document plant species used for treatment of various ailments in the study areas, identify the commonly used plants, parts used, preparation and administration of herbal drugs. To find out the level of consensus or agreement between informants regarding the uses of plants for particular disease categories. Information on the plants was gathered between December 2010 and May 2011 from 124 informants using semi-structured interviews and discussions. For analysis of general use of plants, factor informant consensus (Fic) was used. The reported plants were collected and identified. The study revealed 231plant species belonging to 72 families and 164 genera. These plants were used to treat various diseases and ailments grouped under 14 ailment categories, with the highest number of species (127) being used for gastrointestinal disorders followed by reproductive health disorders (75). The factor informant consensus highlighted low agreement in the use of plants. The highest Fic (0.61) was scored for the digestive problems, such as intestinal worms, stomachache and constipation. Aloe vera was used for malaria with the highest frequency of mention (26 mentions). Herbs (55%) were the main source of medicine followed by shrubs (18%). Leaves (65%) and roots (19%) were the main plant parts used in remedy preparation while decoction was the major form of preparation. Family Asteraceae accounted for 16% of the total species recorded. The majority of plants (53%) were harvested from wild habitats. The most important species according to their fidelity are Senna occidentalis (L.) Link for deworming, Aloe vera L. for malaria, Maytenus senegalensis (Lam) Exell for syphilis and Senecio hadiensis Forssk for miscarriages.The low consensus means the majority of informants do not agree or exchange information on the use of plant species and this may require bioactivity screening to justify the use for the reported ailments. The documented information regarding therapeutic uses provides basic data for further studies focused on pharmacological studies and conservation of the most important species.

  • 16.
    Asiimwe, Savina
    et al.
    Makerere Univ, Sch Biosci, Kampala, Uganda.
    Namutebi, Agnes
    Mugisha, Maud Kamatenesi
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Phytochemical screening, antioxidant activities and mineral composition of nutri-medicinal plants used in the management of opportunistic ailments in HIV/AIDS patientsManuscript (preprint) (Other academic)
  • 17.
    Axelsson, Karolin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Konstanzer, Vera
    Kuttuva Rajarao, Guna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Terenius, Olle
    Dep of Ecology, SLU.
    Seriot, Lisa
    Nordenhem, Henrik
    Dep. of Ecology, SLU.
    Nordlander, Göran
    Dep. of Ecology, SLU.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Antifeedants produced by bacteria associated to the gut of the pine weevil (Hylobius abietis)Manuscript (preprint) (Other academic)
  • 18.
    Axelsson, Karolin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. KTH, School of Biotechnology (BIO).
    Konstanzer, Vera
    KTH.
    Rajarao, Gunaratna Kuttuva
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Terenius, Olle
    Seriot, Lisa
    KTH, School of Biotechnology (BIO).
    Nordenhem, Henrik
    Nordlander, Goran
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Tartu University, Estonia.
    Antifeedants Produced by Bacteria Associated with the Gut of the Pine Weevil Hylobius abietis2017In: Microbial Ecology, ISSN 0095-3628, E-ISSN 1432-184X, Vol. 74, no 1, p. 177-184Article in journal (Refereed)
    Abstract [en]

    The pine weevil, Hylobius abietis, is a severe forest pest insect as it feeds on newly planted conifer seedlings. To identify and develop an antifeedant could be one step towards the protection of seedlings from feeding damage by the pine weevil. With the aim to trace the origin of the antifeedants previously found in feces of the pine weevil, we investigated the culturable bacteria associated with the gut and identified the volatiles they produced. Bacterial isolates were identified by 16S ribosomal RNA gene analysis. The volatile emissions of selected bacteria, cultivated on NB media or on the grated phloem of Scots pine twigs dispersed in water, were collected and analyzed by solid-phase microextraction gas chromatography-mass spectrometry. The bacterial isolates released a variety of compounds, among others 2-methoxyphenol, 2-phenylethanol, 3-methyl-1-butanol, 1-octen-3-ol, 3-octanone, dimethyl disulfide, and dimethyl trisulfide. A strong antifeedant effect was observed by 2-phenylethanol, which could thus be a good candidate for use to protect planted conifer seedlings against feeding damage caused by H. abietis.

  • 19.
    Axelsson, Karolin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Nilsson, Louise
    Nordlander, Göran
    Dep. of Ecology, SLU.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Terenius, Olle
    Dep of Ecology, SLU.
    Do pine weevil microbiota and corresponding volatiles change due to selective feeding?Manuscript (preprint) (Other academic)
  • 20.
    Axelsson, Karolin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Zendegi-Shiraz, Amene
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH). Ferdowsi Univ Mashhad, Dept Chem, Fac Sci, Mashhad, Razavi Khorasan, Iran..
    Swedjemark, Gunilla
    Skogforsk, Ekebo, Svalov, Sweden..
    Borg-Karlson, Anna-Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Mid Sweden Univ, Dept Chem Engn, Sundsvall, Sweden..
    Zhao, Tao
    Örebro Univ, Sch Sci & Technol, SE-70182 Örebro, Sweden..
    Chemical defence responses of Norway spruce to two fungal pathogens2020In: Forest Pathology, ISSN 1437-4781, E-ISSN 1439-0329, Vol. 50, no 6, article id e12640Article in journal (Refereed)
    Abstract [en]

    Constitutive and inducible terpene production is involved in conifer resistance against insects and fungal infestations. To gain knowledge about local defence responses of Norway spruce bark against pathogens and to find potential chemical markers for resistance breeding, we inoculated the stem of 8-year-old Norway spruce (Picea abies) clonal trees with bothEndoconidiophora polonica(Ep, a common fungal pathogen associated with the spruce bark beetleIps typographus) andHeterobasidion parviporum(Hp, a severe pathogen causing root and stem rot disease). Three weeks after inoculation, the fungal-inoculated and intact bark from each tree was sampled. The terpenes in tree bark were extracted with hexane and characterized by gas chromatography-mass spectrometry (GC-MS). The two fungi induced varied terpene responses in the four spruce clones used. Three of the clones showed a 2.3-fold to 5.7-fold stronger terpene response to Hp relative to Ep inoculation, while one clone responded similarly to inoculation with the two fungal pathogens. The amount of the diterpenes thunbergol and geranyllinalool varied between the clones. The level of thunbergol was higher in both intact and fungal-inoculated bark from the less susceptible clones compared with the more susceptible clones. Geranyllinalool was present in higher amounts in the susceptible clones and is thus a possible marker for susceptibility. Our observations show that Norway spruce employs a similar chemical mechanism against the two fungal pathogens. Based on the present and earlier published data, we suggest that certain Norway spruce genotypes have a strong defence reaction against these two pathogens. The diterpenes thunbergol and geranyllinalool might be useful markers of susceptibility in tree-breeding programmes and should be the focus of further detailed investigations.

  • 21.
    Axelsson, Karolin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Zendegi-Shiraz, Amene
    Swedjemark, Gunilla
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Zhao, Tao
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Clone specific chemical defense responses in Norway spruce to infestations by two pathogenic fungi2016In: Forest Pathology, ISSN 1437-4781, E-ISSN 1439-0329Article in journal (Other academic)
    Abstract [en]

    Heterobasidion parviporum (Hp) were investigated using four clones of Norway spruce (Picea abies) with different susceptibility to Heterobasidion sp. Eight year old trees were inoculated with Ep and Hp to minimize the variation due to environment. After three weeks the bark tissue at the upper border of the inoculation hole were extracted with hexane and analyzed by GC-MS. Both treatment and clonal differences were found based on induced mono-, sesqui- and diterpenes. In addition, the Hp produced toxin, fomanoxin, was identified in lowest amount in the most Hp susceptible clone. The clonal trees seem to use different defense strategies towards the two fungi. One of the clones was able to induce strong chemical defense against both fungi, one clone induced chemical defense only against Ep and the most susceptible clone exhibited the least capacity to produce an effective defense against Ep and Hp. Two diterpenes were found to be distinctly different between clones with different susceptibilities, which can be used as chemical indication of Norway spruce resistance against fungi.

    Download full text (pdf)
    fulltext
  • 22.
    Azeem, Muhammad
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. Department of Chemistry, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan.
    Barba Aliaga, Marina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Borg-Karlson, Anna-Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Division of Organic Chemistry, Institute of Technology, Tartu University, Tartu 50411, Estonia.
    Terenius, O.
    Broberg, A.
    Rajarao, Gunaratna Kuttuva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Heterobasidion-growth inhibiting Bacillus subtilis A18 exhibits medium- and age-dependent production of lipopeptides2019In: Microbiological Research, ISSN 0944-5013, E-ISSN 1618-0623, Vol. 223-225, p. 129-136Article in journal (Refereed)
    Abstract [en]

    Heterobasidion annosum s.s. and H. parviporum are severe pathogens of conifers causing butt rot and root rot thus reducing the economic value of timber. Here, the antifungal activity of Bacillus subtilis isolate A18 against these two Heterobasidion species was investigated. Five different culture media with different culture age were investigated to study the effect of substrate composition and culture age for metabolite production. Bacterial cultures and cell-free culture filtrates were tested for antifungal activity. Inhibition of fungal growth was analysed using the agar disc-diffusion method. MALDI-TOF and LC-HRMS analyses were used to identify the antifungal metabolites. Substrate composition and age of culture were found to be active variables with direct effect on the antifungal activity of bacterial culture extracts. High anti-fungal activity was observed when B. subtilis was cultured in PDB, SGB and LB media for four days. Mass-spectrometry analysis showed the presence of lipopeptides in culture filtrates identified as members of the surfactins, polymixins, kurstakins and fengycins. A culture filtrate containing fengycin-type lipopeptides showed the highest bioactivity against Heterobasidion species. Bacterial cultures had higher bioactivity compared to their respective cell free culture filtrates. The results of the present study suggest that B. subtilis A18 is a powerful biocontrol agent against Heterobasidion infections of tree wounds and stumps.

  • 23.
    Azeem, Muhammad
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Borg-Karlson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Environmental Microbiology.
    Antagonistic activity of Bacillus subtilis A18 – A19 against Heterobasidion speciesArticle in journal (Other academic)
  • 24.
    Azeem, Muhammad
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Borg-Karlson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Sustainable bio-production of styrene from forest waste2013In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 144, p. 684-688Article in journal (Refereed)
    Abstract [en]

    A strain of Penicillium expansum was studied for the production of styrene using forest waste biomass as a feeding substrate. The fungal strain was cultivated on bark of various trees supplemented with yeast extract and the volatiles produced were collected on Tenax TA and analyzed by gas chromatography-mass spectrometry. Fungus cultured on grated soft bark of pine (Pinus sylvestris) stems (GPB) and mature bark of oak (Quercus robur) supplemented with yeast extract produced relatively the highest amounts of styrene. The maximum styrene production rate was 52.5 mu g/h, 41 mu g/h and 27 mu g/h from fungus cultivated on 50 mL liquid media with 10 g GPB or mature bark of oak and potato dextrose broth respectively. These promising results suggest that the fungal strain could be used to produce "green" styrene plastics using renewable forest waste biomass.

  • 25.
    Azeem, Muhammad
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Iqbal, Z.
    Emami, S. N.
    Nordlander, G.
    Nordenhem, H.
    Mozūratis, R.
    El-Seedi, Hesham
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Borg-Karlson, Anna-Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Chemical composition and antifeedant activity of some aromatic plants against pine weevil (Hylobius abietis)2020In: Annals of Applied Biology, ISSN 0003-4746, E-ISSN 1744-7348Article in journal (Refereed)
    Abstract [en]

    The pine weevil Hylobius abietis is an important pest causing severe damage to conifer seedlings in reforestation areas in Europe and Asia. Plants that have no evolutionary history with the pine weevil are of special interest in the search for compounds with a strong antifeedant activity. Thus, the essential oils of nine aromatic plants, viz Amomum subulatum, Cinnamomum tamala, Curcuma longa, Laurus nobilis, Ocimum basilicum, Origanum majorana, Origanum vulgare, Syzygium aromaticum and Trachyspermum ammi were extracted by hydrodistillation. The essential oil constituents were identified by gas chromatography–mass spectrometry, and antifeedant properties towards the pine weevil were assessed using choice feeding bioassay. The essential oils of C. longa, O. majorana, S. aromaticum and T. ammi showed an excellent antifeedant activity towards the pine weevil for 24 hr, whereas the essential oil of other plants showed the activity for 6 hr. There was a positive correlation between the amount of benzenoid compounds and the antifeedant activity of the essential oils. This study suggests that pine weevil non-host plant compounds have potential to be used for the protection of seedlings against pine weevil feeding. However, further study will be needed to explore the antifeedant activity of individual components and oils in the laboratory as well as in the field. 

  • 26.
    Azeem, Muhammad
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Environmental Microbiology.
    Nagahama, Kazuhiro
    Terenius, Olle
    Dept of genetics microbiology and toxicology, Stockholm University.
    Nordenhem, Henrik
    SLU, Uppsala.
    Nordlander, Göran
    SLU, Uppsala.
    Borg-Karlson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Chemo- and biodiversity of microbes associated with pine weevil (Hylobius abietis)Manuscript (preprint) (Other academic)
  • 27.
    Azeem, Muhammad
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Environmental Microbiology.
    Nordenhem, Henrik
    SLU, Uppsala.
    Nordlander, Göran
    SLU, Uppsala.
    Borg-Karlson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Penicillium expansum Volatiles Reduce Pine Weevil Attraction to Host Plants2013In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 39, no 1, p. 120-128Article in journal (Refereed)
    Abstract [en]

    The pine weevil Hylobius abietis (L.) is a severe pest of conifer seedlings in reforested areas of Europe and Asia. To identify minimally toxic and ecologically sustainable compounds for protecting newly planted seedlings, we evaluated the volatile metabolites produced by microbes isolated from H. abietis feces and frass. Female weevils deposit feces and chew bark at oviposition sites, presumably thus protecting eggs from feeding conspecifics. We hypothesize that microbes present in feces/frass are responsible for producing compounds that deter weevils. Here, we describe the isolation of a fungus from feces and frass of H. abietis and the biological activity of its volatile metabolites. The fungus was identified by morphological and molecular methods as Penicillium expansum Link ex. Thom. It was cultured on sterilized H. abietis frass medium in glass flasks, and volatiles were collected by SPME and analyzed by GC-MS. The major volatiles of the fungus were styrene and 3-methylanisole. The nutrient conditions for maximum production of styrene and 3-methylanisole were examined. Large quantities of styrene were produced when the fungus was cultured on grated pine bark with yeast extract. In a multi-choice arena test, styrene significantly reduced male and female pine weevils' attraction to cut pieces of Scots pine twigs, whereas 3-methylanisole only reduced male weevil attraction to pine twigs. These studies suggest that metabolites produced by microbes may be useful as compounds for controlling insects, and could serve as sustainable alternatives to synthetic insecticides.

  • 28.
    Azeem, Muhammad
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. COMSATS Inst Informat Technol, Dept Chem, Abbottabad 22060, Pakistan.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Terenius, Olle
    Nordlander, Goran
    Nordenhem, Henrik
    Nagahama, Kazuhiro
    Norin, Emil
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Borg Karlsson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    A fungal metabolite masks the host plant odor for the pine weevil (Hylobius abietis)2015In: Fungal ecology, ISSN 1754-5048, E-ISSN 1878-0083, Vol. 13, p. 103-111Article in journal (Refereed)
    Abstract [en]

    The pine weevil is one of the most important pest insects of conifer reforestation areas in Europe. Female pine weevils cover their eggs with chewed bark and feces (frass) resulting in avoidance behavior of feeding conspecifics towards egg laying sites. It has been suggested that microorganisms present in the frass may be responsible for producing deterrent compounds for the pine weevil. The fungi Ophiostoma canum, O. pluriannulatum, and yeast Debaryomyces hansenii were isolated from aseptically collected pine-weevil frass. The isolated fungi were cultured on weevil frass broth and their volatiles were collected by SPME and identified by GC MS. D. hansenii produced methyl salicylate (MeS) as a major compound, whereas, in addition, O. canum and O. pluriannulatum produced 6-protoilludene. In a multi-choice lab bioassay, MeS strongly reduced pine weevil's attraction to the Pinus sylvestris volatiles. Thus, a fungal metabolite was found that strongly affects the pine weevil host-odor search. (C) 2014 Elsevier Ltd and The British Mycological Society. All rights reserved.

  • 29.
    Azeem, Muhammad
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Norin, Emil
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Terenius, Olle
    Dept of genetics microbiology and toxicology, Stockholm University.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Environmental Microbiology.
    Nordlander, Göran
    SLU, Uppsala.
    Nordenhem, Henrik
    SLU, Uppsala.
    Borg-Karlson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Fungal metabolite mask the host plant odor of the pine weevil (Hylobius abietis)Article in journal (Other academic)
  • 30.
    Azeem, Muhammad
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Department of Chemistry, COMSATS Institute of Information Technology, Abbottabad, Pakistan.
    Terenius, Olle
    Rajarao, Gunaratna Kuttuva
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Nagahama, Kazuhiro
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Sojo University, Faculty of Biotechnology and Life Science, Department of Applied Microbial Technology, 4-22-1 Ikeda, Nishi-ku, Kumamoto, Japan.
    Nordenhem, Henrik
    Nordlander, Goran
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Tartu University, Institute of Technology, Division of Organic Chemistry, Tartu, Estonia.
    Chemodiversity and biodiversity of fungi associated with the pine weevil Hylobius abietis2015In: Fungal Biology, ISSN 1878-6146, E-ISSN 1878-6162, Vol. 119, no 8, p. 738-46Article in journal (Refereed)
    Abstract [en]

    The pine weevil Hylobius abietis is a severe pest of conifer seedlings in reforestation areas. Weevils lay eggs in the root bark or in the soil near roots of recently dead trees and cover the eggs with frass (feces combined with chewed bark), possibly to avoid conspecific egg predation. The aim of the present investigation focused on isolation, identification, and volatile production of fungi from pine-weevil feces and frass. Fungi were isolated from weevil frass and feces separately, followed by identification based on ITS sequencing. Fifty-nine isolates belonging to the genera Penicillium, Ophiostoma, Mucor, Leptographium, Eucasphaeria, Rhizosphaera, Debaryomyces, and Candida were identified. Volatile organic compounds (VOCs) produced by the fungal community and fungal isolates cultured on weevil-frass broth were identified by SPME-GCMS. Major VOCs emitted from the fungal community and pure isolates were species- and strain specific and included isopentylalcohol, styrene, 3-octanone, 6-protoilludene, methyl salicylate, 3-methylanisole, 2-methoxyphenol, and phenol. Some of these are known to influence the orientation of pine weevils when tested among highly attractive newly planted conifer seedlings.

  • 31. Backman, A. C.
    et al.
    Bengtsson, M.
    Borg-Karlson, Anna-Karin
    KTH, Superseded Departments (pre-2005), Chemistry.
    Liblikas, I.
    Witzgall, P.
    Volatiles from apple (Malus domestica) eliciting antennal responses in female codling moth Cydia pomonella (L.) (Lepidoptera: Tortricidae): Effect of plant injury and sampling technique2001In: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 56, no 04-mar, p. 262-268Article in journal (Refereed)
    Abstract [en]

    The antennal responses of codling moth females, Cydia pomonella, to volatiles from apple branches with green fruits were recorded by electroantennography coupled to gas chromatography. The antennae strongly responded to 4,8-dimethyl-1,3(E),7-nonatriene, linalool, beta -caryophyllene, (E)-beta -farnesene, germacrene D, (Z,E)-alpha -farnesene, (E,E)-alpha -farnesene and methyl salicylate. These compounds were all present in volatile collections on Porapak Q from both living and cut branches. Analysis by the solid phase microextraction technique (SPME) showed that the emission of some electrophysiologically active compounds increased after branches had been cut, especially 4,8-dimethyl-1,3(E),7-nonatriene, linalool and (E,E)-alpha -farnesene. The identification of apple volatiles eliciting antennal responses is the first step towards the identification of compounds mediating host-finding and oviposition in codling moth females.

  • 32. Baroffio, C. A.
    et al.
    Guibert, V.
    Richoz, P.
    Rogivue, A.
    Borg-Karlsson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Cross, J.
    Fountain, M.
    Hall, D.
    Ralle, B.
    Sigsgaard, L.
    Trandem, N.
    Wibe, A.
    Management of insect pests using semiochemical traps2016In: Acta Horticulturae, 2016, Vol. 1137, p. 121-127Conference paper (Refereed)
    Abstract [en]

    In the absence of effective control measures, the strawberry blossom weevil (Anthonomus rubi) (SBW) and the raspberry beetle (Byturus tomentosus) (RB) cause large (10 - >80%) losses in yield and quality in organically grown raspberry. Attractive lures for both pests were combined into a single multitrap for the economical management of both of these pests at the same time. This is one of the first approaches to pest management of non-lepidopteran insect pests of horticultural crops using semiochemicals in the EU, and probably the first to target multiple species from different insect orders. The aim is to develop optimized lures and cost-effective trap designs for mass trapping and to determine the optimum density and spatial and temporal patterns of deployment of the traps for controlling these pests by mass trapping. The combination between an aggregation pheromone that attracts Anthonomus rubi and a raspberry flower volatile that attracts Byturus tomentosus seems to be the best combination.

  • 33.
    Baroffio, C. A.
    et al.
    Agroscope, Rte Eterpys 18, CH-1964 Conthey, Switzerland..
    Sigsgaard, L.
    Univ Copenhagen, Dept Plant & Environm Sci, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark..
    Ahrenfeldt, E. J.
    Univ Copenhagen, Dept Plant & Environm Sci, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark..
    Borg-Karlson, Anna-Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Bruun, S. A.
    NIBIO Norwegian Inst Bloecon Res, NO-1431 As, Norway.;NMBU Norwegian Univ Life Sci, Fac Environm Sci & Nat Resource Management, NO-1432 As, Norway..
    Cross, J. V.
    NIAB EMR, New Rd, Kent ME19 6BJ, England..
    Fountain, M. T.
    NIAB EMR, New Rd, Kent ME19 6BJ, England..
    Hall, D.
    Univ Greenwich, Nat Resources Inst, Cent Ave, Chatham ME4 4TB, Kent, England..
    Mozuraitis, R.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Ralle, B.
    LPPRC Latvian Plant Protect Res Ctr, Struktoru Lela 14 A, LV-1039 Riga, Latvia..
    Trandem, N.
    NIBIO Norwegian Inst Bloecon Res, NO-1431 As, Norway.;NMBU Norwegian Univ Life Sci, Fac Environm Sci & Nat Resource Management, NO-1432 As, Norway..
    Wibe, A.
    NORSOK Norwegian Ctr Organ Agr, Gunnars Vei 6, NO-6630 Tingvoll, Norway..
    Combining plant volatiles and pheromones to catch two insect pests in the same trap: Examples from two berry crops2018In: Crop Protection, ISSN 0261-2194, E-ISSN 1873-6904, Vol. 109, p. 1-8Article in journal (Refereed)
    Abstract [en]

    Most horticultural crops are attacked by more than one insect pest. As broad-spectrum chemical control options are becoming increasingly restricted, there is a need to develop novel control methods. Semiochemical attractants are available for three important horticultural pests, strawberry blossom weevil, Anthonomus rubi Herbst (Coleoptera: Curculionidae), European tarnished plant bug, Lygus rugulipennis Poppius (Hemiptera: Miridae) and raspberry beetle, Byturus tomentostts deGeer (Coleoptera: Byturidae). Traps targeting more than one pest species would be more practical and economical for both monitoring and mass trapping than traps for single-species. In this study we aimed to (1) improve the effectiveness of existing traps for insect pests in strawberry and raspberry crops by increasing catches of each species, and (2) test if attractants for two unrelated pest species could be combined to capture both in the same trap without decreasing the total catches. Field tests were carried out in four European countries and different combinations of semiochemicals were compared. A volatile from strawberry flowers, 1,4 dimethoxybenzene (DMB), increased the attractiveness of the aggregation pheromone to both sexes of A. rubi. The host-plant volatile, phenylacetaldehyde (PAA), increased the attraction of female L. rugulipennis to the sex pheromone, and, in strawberry, there was some evidence that adding DMB increased catches further. Traps baited with the aggregation pheromone of A. rubi, DMB, the sex pheromone of L rugulipennis and PAA attracted both target species to the same trap with no significant difference in catches compared to those single-species traps. In raspberry, catches in traps baited with a combination of A. rubi aggregation pheromone, DMB and the commercially available lure for B. tomentosus, based on raspberry flower volatiles, were similar to those in single-species traps. In both crops the efficiency of the traps still needs improvement, but the multi species traps are adequate for monitoring and should not lead to confusion for the user as the target species are easy to distinguish from each other.

  • 34. Bengtsson, M.
    et al.
    Backman, A. C.
    Liblikas, I.
    Ramirez, M. I.
    Borg-Karlson, Anna-Karin
    KTH, Superseded Departments (pre-2005), Chemistry.
    Ansebo, L.
    Anderson, P.
    Lofqvist, J.
    Witzgall, P.
    Plant odor analysis of apple: Antennal response of codling moth females to apple volatiles during phenological development2001In: Journal of Agricultural and Food Chemistry, ISSN 0021-8561, E-ISSN 1520-5118, Vol. 49, no 8, p. 3736-3741Article in journal (Refereed)
    Abstract [en]

    Volatile compounds were collected from apple branches (Malus domestica) at different developmental stages, and the antennal response of codling moth females (Cydia pomonella) to these compounds was recorded by electroantennography coupled to gas chromatography. Presence of a range of terpenoid compounds, many of which had antennal activity, was characteristic for volatile collections from branches with leaves, and from small green apples. Nine compounds from branches with leaves and green fruit consistently elicited an antennal response: methyl salicylate, (E)-beta -farnesene, fi-caryophyllene, 4,8-dimethyl-1,3(E),7-nonatriene, (Z)3-hexenol, (Z,E)-alpha -farnesene, linalool, germacrene D, and (EE)-alpha -farnesene. The bouquet emitted from flowering branches contained in addition several benzenoid compounds which were not found after bloom. Small green apples, which are the main target of codling moth oviposition during the first seasonal flight period, released very few esters. In comparison, fully grown apples released a large number of esters, but fewer terpenoids. The study of apple volatiles eliciting an antennal response, together with a survey of the seasonal change in the release of these compounds, is the first step toward the identification of volatiles mediating host-finding and oviposition in codling moth females.

  • 35.
    Berasategui, Aileen
    et al.
    Dep. of Biochemistry, Max Planck institute for Chemical Ecology.
    Axelsson, Karolin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Nordlander, Göran
    Dep. of Ecology, SLU.
    Schmidt, Axel
    Max Planck Institute for Chemical Ecology.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Gershenzon, Jonathan
    Dep of Biochemistry, Max Planck institute for Chemical Ecology.
    Terenius, Olle
    Dep of Ecology, SLU.
    Kaltenpoth, Martin
    Insect Symbiosis Research Group, Max Planck institute for Chemical Ecology.
    The Gut microbiota of the pine weevil is similar across Europe and resembles that of other conifer-feeding beetles2016In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 25, no 16, p. 4014-4031Article in journal (Refereed)
    Abstract [en]

    The pine weevil (Hylobius abietis, Coleoptera: Curculionidae) is an important pest of conifer seedlings in Europe. Despite its economic importance, little is known about the composition of its gut microbial community and the role it plays in mediating the weevil's ability to utilize conifers as a food source. Here, we characterized the gut bacterial communities of different populations of H. abietis across Europe and compared them to those of other beetles that occupy similar ecological niches. We demonstrate that the microbial community of H. abietis is similar at higher taxonomic levels (family and genus) across locations in Europe, with Wolbachia as the dominant microbe, followed by Enterobacteria and Firmicutes. Despite this similarity, we observed consistent differences between countries and locations, but not sexes. Our meta-analysis demonstrates that the gut bacterial community of the pine weevil is very similar to that of bark beetles that also exploit conifers as a food source. The Enterobacteriaceae symbionts of both host taxa are especially closely related phylogenetically. Conversely, the microbiota of H. abietis is distinct from that of closely related weevils feeding on non-conifer food sources, suggesting that the microbial community of the pine weevil is determined by the environment and may be relevant to host ecology. Furthermore, several H. abietis-associated members of the Enterobacteriaceae family are known to contain genes involved in terpenoid degradation. As such, we hypothesize that the gut microbial community is important for the utilization of conifer seedlings as a food source, either through the detoxification of plant secondary metabolites or supplementation of essential nutrients.

  • 36. Bichao, H.
    et al.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Araujo, J.
    Mustaparta, H.
    Five types of olfactory receptor neurons in the strawberry blossom weevil Anthonomus rubi: Selective responses to inducible host-plant volatiles2005In: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 30, no 2, p. 153-170Article in journal (Refereed)
    Abstract [en]

    Plants release hundreds of volatiles that are important in the interaction with herbivorous animals, but which odorants are detected by which species? In this study, single receptor neurons on the antenna of the oligophagous strawberry blossom weevil Anthonomus rubi were screened for sensitivity to naturally produced plant compounds by the use of gas chromatography linked to electrophysiological recordings from single cells. The narrow tuning of the neurons was demonstrated by responses solely to a few structurally related sesquiterpenes, aromatics or monoterpene hydrocarbons out of hundreds of plant constituents tested. We present five olfactory receptor neuron types, identified according to one primary odorant i.e. the compound to which the neurons are most sensitive. These odorants, (-)-germacrene D, (-)-beta-caryophyllene, methyl salicylate, E-beta-ocimene and (3E)-4,8-dimethyl-1,3,7-nonatriene, present in the intact strawberry plant, are induced in higher amounts by weevil feeding. This suggests that these compounds can provide information about the presence of conspecifics. We used protocols especially designed to allow comparison with previously investigated species. Striking similarities, but also differences, are demonstrated between receptor neuron specificity in the strawberry weevil and moths.

  • 37. Bichao, H.
    et al.
    Borg-Karlson, Anna-Karin
    KTH, Superseded Departments (pre-2005), Chemistry.
    Araujo, J.
    Mustaparta, H.
    Identification of plant odours activating receptor neurones in the weevil Pissodes notatus F. (Coleoptera, Curculionidae)2003In: Journal of Comparative Physiology A. Sensory, neural, and behavioral physiology, ISSN 0340-7594, E-ISSN 1432-1351, Vol. 189, no 3, p. 203-212Article in journal (Refereed)
    Abstract [en]

    Plants release complex mixtures of volatiles important in the interaction with insects and other organisms. In the search for compounds that contribute to the perception of odour quality in the weevil Pissodes notatus, single olfactory receptor neurones on the antennae were screened for sensitivity to naturally produced plant volatiles by the use of gas chromatography linked to single cell recordings. We here present 60 olfactory neurones responding to 25 of the numerous compounds released by host and non-host plants. All the neurones show high selectivity and are classified into 12 distinct types. The two most abundant types respond to alpha-pinene, beta-pinene, and 3-carene (n = 17), and to isopinocamphone and pinocamphone (n = 17), respectively. Other neurone types respond to limonene (n = 9), beta-phellandrene (n = 3), and fenchone (n = 4). Responses to beta-caryophyllene (n = 1) and to ethanol (n = 4) are also shown. Except for two pairs, the neurone types do not show overlap of the molecular receptive range. The active compounds are present in the host, Pinus pinaster, as well as in non-hosts, supporting the idea that plant odour quality is mediated by the ratio of the compounds rather than specific odorants.

  • 38. Bichao, H.
    et al.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Wibe, A.
    Araujo, J.
    Mustaparta, H.
    Molecular receptive ranges of olfactory receptor neurones responding selectively to terpenoids, aliphatic green leaf volatiles and aromatic compounds, in the strawberry blossom weevil Anthonomus rubi2005In: Chemoecology, ISSN 0937-7409, E-ISSN 1423-0445, Vol. 15, no 4, p. 211-226Article in journal (Refereed)
    Abstract [en]

    An important question in insect-plant interactions is which of the numerous plant compounds contribute to the perception of odour qualities in herbivorous insects and are likely to be used as cues in host-searching behaviour. In order to identify which plant-produced volatiles the strawberry blossom weevil Anthonomus rubi detects, we have used electrophysiological recordings from single olfactory neurones linked to gas chromatography and mass spectrometry. We here present 15 receptor neurone types specialised for naturally produced compounds present in the host and nonhost plants and two types for two aggregation pheromone components. The active compounds were terpenoids, aromatic and aliphatic esters, alcohols and aldehydes, some of which are induced by feeding activity of the weevils. The neurones were characterised by a strong response to one or two primary odorants and weaker responses to a few others having similar chemical structure. With one exception, the molecular receptive range of each neurone type was within one chemical group. Enantiomers of linalool separated on a chiral column activated two neurone types with different enantioselectivity. Inhibition by linalool of another neurone type, excited by alpha-pinene, indicated an additional mechanism for coding the information about this compound. Altogether, detection of 54 compounds by olfactory receptor neurones is shown, of which 40 have been chemically identified in this study. Thus A. rubi has the ability to detect a large number of odorants that may be used in host selection behaviour.

  • 39. Bohman, B.
    et al.
    Nordlander, G.
    Nordenhem, H.
    Sunnerheim, K.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Unelius, C. R.
    Structure-activity relationships of phenylpropanoids as antifeedants for the pine weevil Hylobius abietis2008In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 34, no 3, p. 339-352Article in journal (Refereed)
    Abstract [en]

    Ethyl cinnamate has been isolated from the bark of Pinus contorta in the search for antifeedants for the pine weevil, Hylobius abietis. Based on this lead compound, a number of structurally related compounds were synthesized and tested. The usability of the Topliss scheme, a flow diagram previously used in numerous structure-activity relationship (SAR) studies, was evaluated in an attempt to find the most potent antifeedants. The scheme was initially followed stepwise; subsequently, all compounds found in the scheme were compared. In total, 51 phenylpropanoids were tested and analyzed for SARs by using arguments from the field of medicinal chemistry (rational drug design). Individual Hansch parameters based on hydrophobicity, steric, and electronic properties were examined. The effects of position and numbers of substituents on the aromatic ring, the effects of conjugation in the molecules, and the effects of the properties of the parent alcohol part of the esters were also evaluated. It proved difficult to find strong SARs derived from single physicochemical descriptors, but our study led to numerous new, potent, phenylpropanoid antifeedants for the pine weevil. Among the most potent were methyl 3-phenylpropanoates monosubstituted with chloro, fluoro, or methyl groups and the 3,4-dichlorinated methyl 3-phenylpropanoate.

  • 40.
    Borg-Karlson, Anna-Karin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Nordlander, R.
    Mudalige, A.
    Nordenhem, H.
    Unelius, C. R.
    Antifeedants in the feces of the pine weevil Hylobius abietis: Identification and biological activity2006In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 32, no 5, p. 943-957Article in journal (Refereed)
    Abstract [en]

    Egg-laying females of the pine weevil, Hylobius abietis (L.), regularly deposit feces adjacent to each egg. Egg cavities are gnawed in the bark of roots of recently dead conifer trees. After egg deposition, the cavity is sealed by feces and a plug of bark fragments. Root bark containing egg cavities with feces is avoided as food by pine weevils, which indicates the presence of natural antifeedants. Here we present the first results of the isolation and chemical analyses of antifeedant compounds in the feces of H. abietis. In feeding bioassays, methanol extracts of the feces revealed strong antifeedant properties. Methanol extracts were fractionated by medium-pressure liquid chromatography and the antifeedant effects were mainly found in the fractions of highest polarity. Volatile compounds in the active fractions were identified by gas chromatography-mass spectrometry (GC-MS) and the nonvolatile compounds were characterized by pyrolysis-GC-MS. Based on mass spectra, a number of compounds with various chemical structures were selected to be tested for their antifeedant properties. Antifeedant effects were found among compounds apparently originating from lignin: e.g., a methylanisol, guaiacol, veratrol, dihydroxybenzenes, and dihydroconiferyl alcohol. A weak effect by fatty acid derivatives was found. The types of naturally occurring antifeedant compounds identified in this study may become useful for the protection of planted conifer seedlings against damage by H. abietis.

  • 41.
    Borg-Karlson, Anna-Karin
    et al.
    KTH, Superseded Departments (pre-2005), Chemistry.
    Tengo, J.
    Valterova, I.
    Unelius, C. R.
    Taghizadeh, T.
    Tolasch, T.
    Francke, W.
    (S)-(+)-linalool, a mate attractant pheromone component in the bee Colletes cunicularius2003In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 29, no 1, p. 1-14Article in journal (Refereed)
    Abstract [en]

    Enantiomerically pure (S)-(+)- linalool was the main constituent in the extracts of the cephalic secretions of virgin females, mated females, freshly emerged males, and patrolling males of the solitary bee Colletes cunicularius. After copulation, the content of (S)-(+)- linalool emitted by the female was strongly reduced. Electrophysiological experiments revealed that both enantiomers of linalool elicited responses from the antennae of the males. Field tests using the pure enantiomers and the racemate of linalool showed that the number of male bees attracted was highest for (S)-(+)- linalool. The search flight activity in the mating flight area increased dramatically when patrolling males were presented with (S)-(+)- linalool vs (R)-(+)- linalool. Taken together, these data indicate a mate attractant pheromone function of (S)-(+)- linalool.

  • 42. Buda, Vincas
    et al.
    Mozuraitis, Raimondas
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kutra, Jonas
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    p-Cresol: A Sex Pheromone Component Identified from the Estrous Urine of Mares2012In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 38, no 7, p. 811-813Article in journal (Refereed)
    Abstract [en]

    Previously it was shown that m- and p-cresols in the urine of mares exhibits a temporally reproducible pattern that is dependent on ovarian activity and, thus, provides information about the timing of ovulation. New behavioral data demonstrate 1) that stallions spend significantly more time sniffing p-cresol as compared to o-, and m-cresols, and, 2) that the extent of stallions' erections differ significantly in response to different types of samples. The lowest erection level was recorded for the pure-water control, a moderate erection level was elicited by the urine of diestrous mares, and the highest erection level was elicited by urine of a diestrous mare containing synthetic p-cresol at a quantity equivalent to half of the amount of p-cresol found in the urine of estrous mares. Consequently, p-cresol is at least one of the components of a horse sex pheromone.

  • 43. Chen, Shao
    et al.
    Yuxin, Pei
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Zhichao, Pei
    Regioselective Acylation of 2 '- or 3 '-Hydroxyl Group in Salicin: Hemisynthesis of Acylated Salicins2014In: Chemical Research in Chinese Universities, ISSN 1005-9040, E-ISSN 2210-3171, Vol. 30, no 5, p. 774-777Article in journal (Refereed)
    Abstract [en]

    Salicin-based phenolic glycosides(PGs) are important defensive substances against herbivore feeding and have good bioactivities. In this work, a novel approach for the synthesis of salicin-based PGs has been developed, by which PGs of 2'-O-acetylsalicin(5a), 3'-O-acetylsalicin(5b) and 3'-O-benzoylsalicin(5d) were hemisynthesized. The effects of acylation reagent, solvent and temperature on the regioselective acylation of 2'- or 3'-hydroxyl groups of salicin mediated by dibutyltin oxide were investigated. The optimal conditions under which the best regioselectivity reached for 5a-5d were discovered, respectively. Moreover, a tentative tin-oxygen coordination mechanism was put forward to explain the different regioselectivities shown under different conditions.

  • 44.
    Danielsson, Marie
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Tracing induced stress sites in conifers by single needle analysesManuscript (preprint) (Other academic)
  • 45.
    Danielsson, Marie
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kännaste, Astrid
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Lindström, Anders
    School of Industrial Technology and Management, Dalarna University.
    Hellqvist, Claes
    Department of Ecology, Swedish University of Agricultural Sciences.
    Stattin, Eva
    School of Industrial Technology and Management, Dalarna University.
    Långström, Bo
    Department of Ecology, Swedish University of Agricultural Sciences.
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Mini-seedlings of Picea abies are less attacked by Hylobius abietis than conventional ones: Is plant chemistry the explanation?2008In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 23, no 4, p. 299-306Article in journal (Refereed)
    Abstract [en]

    The pine weevil, Hylobius abietis (L.), is a major pest in conifer reforestation areas in the Palaearctic region. Size and chemistry of the seedlings may explain the damage rates in plantations. The performance of 10-week containerized seedlings (mini-seedlings) was compared with 1-year-old conventional seedlings of Norway spruce, Picea abies (L.), in a field experiment in central Sweden. After 2 years the weevil damage was lower for the mini-seedlings than for the conventional seedlings (3.5 vs 55%). After 3 years, the overall survival was 82 and 75%, respectively. Weevil damage was the main cause of mortality for conventional seedlings, whereas mini-seedlings mainly died from drought. Volatiles of the two seedling types were compared by solid-phase microextraction-gas chromatography -mass spectrometry (SPME-GC-MS). Unwounded mini-seedlings and conventional seedlings differed in their compositions of monoterpenes and sesquiterpenes. Miniseedlings mainly emitted limonene, known to be repellent to the pine weevil. When wounded, green leaf volatiles were released by mini-seedlings while the pine weevil attractant alpha-pinene was released by conventional seedlings. Volatiles may partly explain the mini-seedlings' resistance against weevil attack. Further studies are needed to clarify how long this miniseedling effect remains.

  • 46.
    Danielsson, Marie
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Lunden, Karl
    Elfstrand, Malin
    Hu, Jiang
    Zhao, Tao
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Arnerup, Jenny
    Ihrmark, Katarina
    Swedjemark, Gunilla
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Stenlid, Jan
    Chemical and transcriptional responses of Norway spruce genotypes with different susceptibility to Heterobasidion spp. infection2011In: BMC Plant Biology, E-ISSN 1471-2229, Vol. 11, p. 154-Article in journal (Refereed)
    Abstract [en]

    Background: Norway spruce [Picea abies (L.) Karst.] is one of the most important conifer species in Europe. The wood is economically important and infections by wood-rotting fungi cause substantial losses to the industry. The first line of defence in a Norway spruce tree is the bark. It is a very efficient barrier against infection based on its mechanical and chemical properties. Once an injury or an infection is recognized by the tree, induced defences are activated. In this study we examined transcriptional response, using 454-sequencing, and chemical profiles in bark of Norway spruce trees with different susceptibility to Heterobasidion annosum s.l. infection. The aim was to find associations between the transcriptome and chemical profiles to the level of susceptibility to Heterobasidion spp. in Norway spruce genotypes. Results: Both terpene and phenol compositions were analysed and at 28 days post inoculation (dpi) high levels of 3-carene was produced in response to H. annosum. However, significant patterns relating to inoculation or to genotypes with higher or lower susceptibility could only be found in the phenol fraction. The levels of the flavonoid catechin, which is polymerized into proanthocyanidins (PA), showed a temporal variation; it accumulated between 5 and 15 dpi in response to H. annosum infection in the less susceptible genotypes. The transcriptome data suggested that the accumulation of free catechin was preceded by an induction of genes in the flavonoid and PA biosynthesis pathway such as leucoanthocyanidin reductase. Quantitative PCR analyses verified the induction of genes in the phenylpropanoid and flavonoid pathway. The qPCR data also highlighted genotype-dependent differences in the transcriptional regulation of these pathways. Conclusions: The varying dynamics in transcriptional and chemical patterns displayed by the less susceptible genotypes suggest that there is a genotypic variation in successful spruce defence strategies against Heterobasidion. However, both high levels of piceasides and flavonoids in the less susceptible genotypes suggested the importance of the phenolic compounds in the defence. Clearly an extended comparison of the transcriptional responses in the interaction with Heterobasidion between several independent genotypes exhibiting reduced susceptibility is needed to catalogue mechanisms of successful host defence strategies.

  • 47.
    Danielsson, Marie
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Lundén, Karl
    Arnerup, Jenny
    Hu, Jiang
    Zhao, Tao
    Swedjemark, Gunilla
    Elfstrand, Malin
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Stenlid, Jan
    Chemical and transcriptional responses of Norway spruce clones with different susceptibility to Heterobasidion spp. infectionManuscript (preprint) (Other academic)
  • 48.
    Danielsson, Marie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Zhao, Tao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Department of Science and Technology, Örebro University, Örebro, Sweden.
    Borg-Karlson, Anna-Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Arthropod infestation sites and induced defence can be traced by emission from single spruce needles2019In: Arthropod-Plant Interactions, ISSN 1872-8855, E-ISSN 1872-8847, Vol. 13, no 2, p. 253-259Article in journal (Refereed)
    Abstract [en]

    Emissions of defence chemicals from Norway spruce seedlings can be induced by feeding arthropods or by exogenous hormonal application. Some defence chemicals may attract or repel associated arthropods. The aim of this study was to show that it is possible to detect and collect stress-induced volatiles from micro sites, such as at the scale of a single needle, in vivo by using SPME. Methyl jasmonate application on the stem of Norway spruce seedlings induced emission of (E)-beta-farnesene only from the needles closest to the application site. Emissions of (E)-beta-farnesene, (E,E)-alpha-farnesene and (E)-alpha-bisabolene were only detected from needles infested by the spider mite Oligonychus ununguis. The total volatile amount detected by SPME-GC-MS reached a considerable mass of 14 ng/needle/24 h, suggesting that emission from damaged and stressed conifers might have a larger impact on the macro climate than previously estimated.

  • 49. Ehrlén, J.
    et al.
    Borg-Karlson, Anna Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kolb, A.
    Selection on plant optical traits and floral scent: Effects via seed development and antagonistic interactions2012In: Basic and Applied Ecology, ISSN 1439-1791, E-ISSN 1618-0089, Vol. 13, no 6, p. 509-515Article in journal (Refereed)
    Abstract [en]

    Evolutionary explanations of plant reproductive traits have usually emphasized optical characteristics of plants and selection mediated by pollinators. In recent years, studies have been broadened by incorporating also interactions with antagonists and by studying plant fragrant cues. Here, we examined if optical and fragrance traits of the perennial herb Primula veris correlated with reproductive success, in terms of fruit and seed set, and with avoidance of seed predators. Selection path analysis showed that both optical and fragrance traits influenced total seed production, and effects occurred both via fruit and seed set and via predator avoidance. In one case the same trait, inflorescence height, influenced total seed production both positively and negatively through effects on different components of fitness. Our results lend support to the notion that selection by mutualists and antagonists simultaneously acts on optical and fragrance traits.

  • 50.
    Elmhalli, Fawzeia
    et al.
    Uppsala Univ, Dept Systemat Biol, Evolutionary Biol Ctr, Norbyvagen 18D, S-75536 Uppsala, Sweden.;Univ Benghazi, Fac Publ Hlth, Dept Environm Hlth, Benghazi, Libya..
    Garboui, Samira S.
    Univ Benghazi, Fac Publ Hlth, Dept Environm Hlth, Benghazi, Libya..
    Borg-Karlson, Anna-Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Mozuraitis, Raimondas
    Stockholm Univ, Dept Zool, Svante Arrhenius Vag 18B, S-11418 Stockholm, Sweden..
    Baldauf, Sandra L.
    Uppsala Univ, Dept Systemat Biol, Evolutionary Biol Ctr, Norbyvagen 18D, S-75536 Uppsala, Sweden..
    Grandi, Giulio
    Swedish Univ Agr Sci SLU, Dept Biomed Sci & Vet Publ Hlth, Box 7036,Ulls Vag 26, S-75651 Uppsala, Sweden.;Natl Vet Inst SVA, Dept Microbiol, Ulls Vag 2B, S-75651 Uppsala, Sweden..
    Acaricidal activity against Ixodes ricinus nymphs of essential oils from the Libyan plants Artemisia herba alba, Origanum majorana and Juniperus phoenicea2021In: Veterinary Parasitology: Regional Studies and Reports, E-ISSN 2405-9390, Vol. 24, article id 100575Article in journal (Refereed)
    Abstract [en]

    Ixodes ricinus (L.) (Acari: Ixodidae) is a major vector for the transmission of several important human pathogens. The aim of the present study was to evaluate the in vitro efficacy of different concentrations of essential oils (Eos) on I. ricinus tick nymphs. Oils were obtained from the leaves of three plants native to Libya: white wormwood (Artemisia herba alba Asso), marjoram (Origanum majorana L.) and Arar (Juniperus phoenicea L., English common name Phoenician juniper). Assays were done using the "open filter paper method". Two concentrations from each oil, 0.5 and 1 mu l/cm, were tested. The acaricidal effect was measured in terms of the lethal concentrations (LC50, LC95) and lethal time (LT50, LT95). Mortality rates were obtained by counting the surviving nymphs every 30 min for the first five hours and then at 24, 48 and 72 h. A mortality of 100% was recorded at the higher concentration of oils (1 mu l/cm(2)) from A. herba alba and J. phoenicea at the first 2 h of exposure. Exposure to O. majorana led to 100% mortality on the third day (72 h), and this effect decreased noticeably with 0.5 mu l/cm(2) oil at the same exposure time. However, 50% of ticks showed a paralysis effect and less movement after 2 h. The LC50 of mortality was reached within the first 24 h of exposure time at 0.5 mu l/cm(2) of O. majorana, which produced 60% tick's mortality. Chemical composition of the essential oils was elucidated by gas chromatography-mass spectrometry analyses. These results suggest that essential oils deserve further investigation as components of alternative approaches for I. ricinus tick control.

1234 1 - 50 of 157
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • 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