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Hanna Mustaparta - One of the best experts on this subject based on the ideXlab platform.
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associative learning of plant odorants activating the same or different receptor neurones in the moth heliothis virescens
The Journal of Experimental Biology, 2005Co-Authors: H T Skiri, M Stranden, Jeanchristophe Sandoz, Randolf Menzel, Hanna MustapartaAbstract:The importance of olfactory learning in host plant selection is well demonstrated in insects, including the heliothine moths. In the present study olfactory conditioning of the proboscis extension response was performed to determine the moths' ability to learn and discriminate three plant odorants: beta-ocimene and Beta-Myrcene (activating the same receptor neurone type), and racemic linalool (activating two different types). The conditioned stimulus (CS) was an air puff with each odorant blown into a constant air stream and over the antennae, and the unconditioned stimulus (US) was sucrose solution applied first to the antennal taste sensilla, then to the proboscis. Conditioning with increasing odorant concentrations induced increased learning performance. The concentration threshold for learning was 100 times lower for racemic linalool than for the two other odorants, a fact that can be correlated with a higher sensitivity of the moths' antennae to racemic linalool as shown in electroantennogram recordings. After correcting for the different odour sensitivities, the moths' ability to discriminate the odorants was studied. Differential conditioning experiments were carried out, in which moths had to distinguish between a rewarded (CS+) odorant and an explicitly unrewarded odorant (CS-), choosing odour concentrations giving the same learning rate in previous experiments. The best discrimination was found with Beta-Myrcene as the rewarded odorant and racemic linalool as the unrewarded. The opposite combination gave lower discrimination, indicating a higher salience for Beta-Myrcene than for racemic linalool. The moths could also discriminate between beta-ocimene and Beta-Myrcene, which was surprising, since they activate the same receptor neurone type. No difference in salience was found between these two odorants.
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selective receptor neurone responses to e beta ocimene beta myrcene e e alpha farnesene and homo farnesene in the moth heliothis virescens identified by gas chromatography linked to electrophysiology
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2000Co-Authors: T. Rostelien, Annakarin Borgkarlson, Hanna MustapartaAbstract:An important question in olfaction is for which odorants receptor neurones have evolved. In the present study, olfactory receptor neurones on the antennae of the tobacco budworm moth Heliothis virescens were screened for sensitivity to naturally occurring plant-produced volatiles by the use of gas chromatography linked to electrophysiology. Volatiles of host as well as non-host plants collected by headspace techniques were used for stimulating the neurones, sequentially via two columns, one polar and one nonpolar installed in parallel in the gas chromatograph. Three types of neurones presented in this paper responded to one, two or three compounds for which the retention times were determined in both column types. The chemical structures of the active components were determined on the basis of mass spectrometry linked to gas chromatography, indicating E-β-ocimene and β-myrcene as stimulants for neurone type 1, E,E-α-farnesene for neurone type 2 and homo-farnesene for neurone type 3. Re-testing authentic materials verified the identifications for the type 1 neurones. The results demonstrate a high specificity for the three types of neurones by strong responses to one or two structurally similar compounds out of hundreds present in a large variety of plants. The study exemplifies plant odour detection by narrowly tuned receptor neurones in a polyphagous moth species.
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Selective receptor neurone responses to E-beta-ocimene, Beta-Myrcene, E.E.-alpha-farnesene and homo-farnesene in the moth Heliothis virescens, identified by gas chromatography linked to electrophysiology A Neuroethology, sensory, neural, and behavior
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2000Co-Authors: T. Rostelien, Anna-karin Borg-karlson, Hanna MustapartaAbstract:An important question in olfaction is for which odorants receptor neurones have evolved. In the present study, olfactory receptor neurones on the antennae of the tobacco budworm moth Heliothis virescens were screened for sensitivity to naturally occurring plant-produced volatiles by the use of gas chromatography linked to electrophysiology. Volatiles of host as well as non-host plants collected by headspace techniques were used for stimulating the neurones, sequentially via two columns, one polar and one non-polar installed in parallel in the gas chromatograph. Three types of neurones presented in this paper responded to one, two or three compounds for which the retention times were determined in both column types. The chemical structures of the active components were determined on the basis of mass spectrometry linked to gas chromatography, indicating E-beta-ocimene and Beta-Myrcene as stimulants for neurone type 1, E,E-alpha-farnesene for neurone type 2 and homo-farnesene for neurone type 3. Re-testing authentic materials verified the identifications for the type 1 neurones. The results demonstrate a high specificity for the three types of neurones by strong responses to one or two structurally similar compounds out of hundreds present in a large variety of plants. The study exemplifies plant odour detection by narrowly tuned receptor neurones in a polyphagous moth species.
T. Rostelien - One of the best experts on this subject based on the ideXlab platform.
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selective receptor neurone responses to e beta ocimene beta myrcene e e alpha farnesene and homo farnesene in the moth heliothis virescens identified by gas chromatography linked to electrophysiology
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2000Co-Authors: T. Rostelien, Annakarin Borgkarlson, Hanna MustapartaAbstract:An important question in olfaction is for which odorants receptor neurones have evolved. In the present study, olfactory receptor neurones on the antennae of the tobacco budworm moth Heliothis virescens were screened for sensitivity to naturally occurring plant-produced volatiles by the use of gas chromatography linked to electrophysiology. Volatiles of host as well as non-host plants collected by headspace techniques were used for stimulating the neurones, sequentially via two columns, one polar and one nonpolar installed in parallel in the gas chromatograph. Three types of neurones presented in this paper responded to one, two or three compounds for which the retention times were determined in both column types. The chemical structures of the active components were determined on the basis of mass spectrometry linked to gas chromatography, indicating E-β-ocimene and β-myrcene as stimulants for neurone type 1, E,E-α-farnesene for neurone type 2 and homo-farnesene for neurone type 3. Re-testing authentic materials verified the identifications for the type 1 neurones. The results demonstrate a high specificity for the three types of neurones by strong responses to one or two structurally similar compounds out of hundreds present in a large variety of plants. The study exemplifies plant odour detection by narrowly tuned receptor neurones in a polyphagous moth species.
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Selective receptor neurone responses to E-beta-ocimene, Beta-Myrcene, E.E.-alpha-farnesene and homo-farnesene in the moth Heliothis virescens, identified by gas chromatography linked to electrophysiology A Neuroethology, sensory, neural, and behavior
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2000Co-Authors: T. Rostelien, Anna-karin Borg-karlson, Hanna MustapartaAbstract:An important question in olfaction is for which odorants receptor neurones have evolved. In the present study, olfactory receptor neurones on the antennae of the tobacco budworm moth Heliothis virescens were screened for sensitivity to naturally occurring plant-produced volatiles by the use of gas chromatography linked to electrophysiology. Volatiles of host as well as non-host plants collected by headspace techniques were used for stimulating the neurones, sequentially via two columns, one polar and one non-polar installed in parallel in the gas chromatograph. Three types of neurones presented in this paper responded to one, two or three compounds for which the retention times were determined in both column types. The chemical structures of the active components were determined on the basis of mass spectrometry linked to gas chromatography, indicating E-beta-ocimene and Beta-Myrcene as stimulants for neurone type 1, E,E-alpha-farnesene for neurone type 2 and homo-farnesene for neurone type 3. Re-testing authentic materials verified the identifications for the type 1 neurones. The results demonstrate a high specificity for the three types of neurones by strong responses to one or two structurally similar compounds out of hundreds present in a large variety of plants. The study exemplifies plant odour detection by narrowly tuned receptor neurones in a polyphagous moth species.
Hervé Casabianca - One of the best experts on this subject based on the ideXlab platform.
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Chemical differentiation of Boswellia sacra and Boswellia carterii essential oils by gas chromatography and chiral gas chromatography–mass spectrometry
Journal of Chromatography A, 2012Co-Authors: Cole Woolley, Mahmoud M. Suhail, Brett L. Smith, Karen E. Boren, Lindsey C. Taylor, Marc Schreuder, Jeremiah K. Chai, Hervé CasabiancaAbstract:Major botanical and scientific references currently identify two species of frankincense, Boswellia carterii and Boswellia sacra, as being synonymous. We evaluated the Somalian (B. carterii) and Omani/Yemeni (B. sacra) species by chemical analyses to determine if there were any minor or major differences between the two species of frankincense. Components identified with their average percent for B. sacra are alpha-thujene (0.6%), alpha-pinene (68.2%), camphene (2.1%), sabinene (2.9%), beta-pinene (2.0%), myrcene (0.7%), limonene+beta-phellandrene (6.2%). Components identified with their average percent for B. carterii are alpha-thujene (7.9%), alpha-pinene (37.3%), camphene (0.8%), sabinene (4.9%), beta-pinene (1.8%), myrcene (7.3%), limonene+beta-phellandrene (14.4%). Initially, GC-MS analysis did not reveal major statistical differences. However, optical rotation values, B. Sacra (+30.1 degrees ) and B. carterii (-13.3 degrees ), demonstrated a greater significant difference. Enantiomeric ratio (+)/(-) values of alpha-pinene for B. sacra and B. carterii are 8.24 and 0.68, respectively, were also calculated aiding our conclusion that B. sacra and B. carterii are not synonymous but rather two distinct and individual frankincense species.
Vicki Schlegel - One of the best experts on this subject based on the ideXlab platform.
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Distillation time modifies essential oil yield, composition, and antioxidant capacity of fennel (Foeniculum vulgare Mill)
Journal of Oleo Science, 2013Co-Authors: Valtcho D. Zheljazkov, Tess Astatkie, Thomas Horgan, Vicki SchlegelAbstract:Fennel (Foeniculum vulgare Mill) is an essential oil crop grown worldwide for production of essential oil, as medicinal or as culinary herb. The essential oil is extracted via steam distillation either from the whole aboveground biomass (herb) or from fennel fruits (seed). The hypothesis of this study was that distillation time (DT) can modify fennel oil yield, composition, and antioxidant capacity of the oil. Therefore, the objective of this study was to evaluate the effect of eight DT (1.25, 2.5, 5, 10, 20, 40, 80, and 160 min) on fennel herb essential oil. Fennel essential oil yield (content) reached a maximum of 0.68% at 160 min DT. The concentration of trans-anethole (32.6-59.4% range in the oil) was low at 1.25 min DT, and increased with an increase of the DT. Alpha-phelandrene (0.9-10.5% range) was the lowest at 1.25 min DT and higher at 10, 80, and 160 min DT. Alpha-pinene (7.1-12.4% range) and beta-pinene (0.95-1.64% range) were higher in the shortest DT and the lowest at 80 min DT. Myrcene (0.93-1.95% range), delta-3-carene (2.1-3.7% range), cis-ocimene (0-0.23% range), and gamma-terpinene (0.22-2.67% range) were the lowest at 1.25 min DT and the highest at 160 min DT. In contrast, the concentrations of paracymene (0.68-5.97% range), fenchone (9.8-22.7% range), camphor (0.21-0.51% range), and cis-anethole (0.14-4.66% range) were highest at shorter DT (1.25-5 min DT) and the lowest at the longer DT (80-160 min DT). Fennel oils from the 20 and 160 min DT had higher antioxidant capacity than the fennel oil obtained at 1.25 min DT. DT can be used to obtain fennel essential oil with differential composition. DT must be reported when reporting essential oil content and composition of fennel essential oil. The results from this study may be used to compare reports in which different DT to extract essential oil from fennel biomass were used.
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Distillation time alters essential oil yield, composition and antioxidant activity of female Juniperus scopulorum trees
Journal of Essential Oil Research, 2013Co-Authors: Valtcho D. Zheljazkov, Ekaterina Jeliazkova, Adrienne O. Tatman, Tess Astatkie, Vicki SchlegelAbstract:The objective of this study was to evaluate the effect of distillation time (DT) (1.25, 2.5, 5, 10, 20, 40, 80, 160, 240, 360, 480 minutes) on yield, oil profile and antioxidant capacity of female Juniperus scopulorum trees. Analysis of the data revealed that essential oil yields reached a maximum of 0.77% at 240 minutes DT; the concentrations of alpha-thujene, alpha-pinene, camphene, myrcene and para-cymene decreased with longer DT; and the concentrations of cis-sabinene hydrate and linalool/trans-sabinene hydrate reached maximum at 40 minutes DT, whereas that of pregeijerene-B, delta-carene reached maximum at 240 minutes DT. The concentrations of alpha-terpinene, limonene, gamma-terpinene and 4-terpineol reached their maximum at 360 minutes DT, whereas terpinolene, alpha-eudesmol/beta-eudesmol and 8-alpha acetoxyelemol reached maximum at 480 minutes DT. The yield of various essential oil constituents increased with increasing DT and reached maximum at 240 minutes or longer. The antioxidant capacity of J...
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effects of distillation time on the pinus ponderosa essential oil yield composition and antioxidant activity
Hortscience, 2012Co-Authors: Valtcho D. Zheljazkov, Tess Astatkie, Vicki SchlegelAbstract:This study evaluated the effect of distillation time (DT; 1.25, 2.5, 5, 10, 20, 40, 80, 160, 240, and 360 min) on essential oil yield, composition, and the antioxidant activity of ponderosa pine essential oil. Pine essential oil yield increased with length of the DT and reached maximum at 160 min DT. The major oil constituents were alpha-pinene and beta-pinene, ranging from 17% to 40% and from 21% to 29%, respectively, of the total oil. Overall, the concentration of alpha-pinene and beta-pinene was high at the initial DT (5-20 min) and decreased with increasing DT. The concentration of myrcene (range, 0.9% to 1.5%) was lowest at 5 min DT, then increased at 10 min DT, and did not change with longer DT. Overall, the concentrations of most other constituents (delta-3-carene, limonene, cis-ocimene, alpha-terpinyl acetate, germacrene-D, alpha-muurolene, gamma- cadinene, delta-cadinene, and germacrene-D-4-ol) were low at the initial DT and increased with increasing DT. Total yields (a function of oil yield and the concentration of individual constituents) of all constituents were generally the lowest at 5 min DT, increased with increasing DT, and reached maximum at 160 min DT. The antioxidant capacity of the pine oil in this study varied between 7.0 and 14.5 mmole Trolox/g and was unaffected by DT. This study demonstrated that DT can significantly modify the essential oil yield and composition of ponderosa pine needles. Furthermore, DT could be used to obtain pine oil with targeted chemical profiles. This report can also be used as a reference point for comparing literature reports, in which different DTs are used to extract essential oil of ponderosa pine.
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Distillation time alters essential oil yield, composition, and antioxidant activity of male Juniperus scopulorum trees
Journal of oleo science, 2012Co-Authors: Valtcho D. Zheljazkov, Ekaterina Jeliazkova, Tess Astatkie, Vicki SchlegelAbstract:The objective of this study was to evaluate the effect of 15 distillation times (DT), ranging from 1.25 to 960 min, on oil yield, essential oil profiles, and antioxidant capacity of male J. scopulorum trees. Essential oil yields were 0.07% at 1.25 min DT and reached a maximum of 1.48% at 840 min DT. The concentrations of alpha-thujene (1.76-2.75%), alpha-pinene (2.9-8.7%), sabinene (45-74.7%), myrcene (2.4-3.4%), and para-cymene (0.8-3.1%) were highest at the shortest DT (1.5 to 5 min) and decreased with increasing DT. Cis-sabinene hydrate (0.5-0.97%) and linalool plus trans-sabinene (0.56-1.6%) reached maximum levels at 40 min DT. Maximum concentrations of limonene (2.3-2.8%) and pregeijerene-B (0.06-1.4%) were obtained at 360-480 min DT, and 4-terpinenol (0.7-5.7%) at 480 min DT. Alpha-terpinene (0.16-2.9%), gamma-terpinene (0.3-4.9%) and terpinolene (0.3-1.4%) reached maximum at 720 min DT. The concentrations of delta-cadinene (0.06-1.65%), elemol (0-6.0%), and 8-alpha-acetoxyelemol (0-4.4%) reached maximum at 840 min DT. The yield of the essential oil constituents increased with increasing DT. Only linalool/transsabinene hydrate reached a maximum yield at 360 min DT. Maximum yields of the following constituents were obtained at 720 min DT: alpha-thujene, alpha-pinene, camphene, sabinene, myrcene, alpha-terpinene, para-cimene, limonene, gamma-terpinene, terpinolene, and 4-terpinenol. At 840 min DT, cis-sabinene hydrate, prejeijerene-B, gamma muurolene, delta-cadinene, reached maximum. At 960 min DT, maximum yields of beta-pinene, elemol, alphaeudesmol/betaeudesmol, 8-alpha-acetoxyelemol were reached. These changes were adequately modeled by either the Michaelis-Menten or the Power (Convex) nonlinear regression models. Oils from the 480 min DT showed higher antioxidant activity compared to samples collected at 40, 160, or 960 min DT. These results show the potential for obtaining essential oils with various compositions and antioxidant capacity from male J. scopulorum by varying DT. This study can be used as a reference paper for comparing results of reports where different lengths of the DT were used.
Annakarin Borgkarlson - One of the best experts on this subject based on the ideXlab platform.
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evaluation of extracts and oils of mosquito diptera culicidae repellent plants from sweden and guinea bissau
Journal of Medical Entomology, 2006Co-Authors: Thomas G T Jaenson, Katinka Palsson, Annakarin BorgkarlsonAbstract:In laboratory tests, ethyl acetate extracts of Hyptis suaveolens Poit. from Guinea-Bissau and Rhododendon tomentosum (Stokes) H. Harmaja (formerly Ledum palustre L.) and Myrica gale L. significantly reduced probing activity of Aedes aegypti (L.). In the field in southern Sweden, extracts of leaves of R. tomentosum, M. gale, and Achillea millefolium L. significantly reduced biting by Aedes mosquitoes. Volatile compounds from M. gale, R. tomentosum, A. millefolium, and H. suaveolens were collected by solid phase microextraction (SPME). Alternatively, compounds in the plants were subjected to extraction by organic solvents of different polarities or by steam distillation and collection by SPME. Compounds collected were identified by gas chromatography-mass spectrometry. Leaves of H. suaveolens contained mainly beta-caryophyllene, bergamotene, and terpinolene. The volatile fraction of an ethyl acetate extract of H. suaveolens was collected by SPME and included beta-caryophyllene, (-) -sabinene, beta-pinene, limonene, alpha-pinene, and bergamotene. The main volatiles detected were alpha-pinene, alpha-phellandrene, myrcene, and limonene from M. gale leaves or inflorescences; pcymene, sabinene, and terpinyl acetate from leaves of R. tomentosum; and (-)-germacrene D, beta-pinene, sabinene, and alpha-pinene from A. millefolium leaves or inflorescences. The selected plant species contained numerous volatiles known to have insecticidal, acaricidal, "pesticidal," and/ or insect repellent properties.
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selective receptor neurone responses to e beta ocimene beta myrcene e e alpha farnesene and homo farnesene in the moth heliothis virescens identified by gas chromatography linked to electrophysiology
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2000Co-Authors: T. Rostelien, Annakarin Borgkarlson, Hanna MustapartaAbstract:An important question in olfaction is for which odorants receptor neurones have evolved. In the present study, olfactory receptor neurones on the antennae of the tobacco budworm moth Heliothis virescens were screened for sensitivity to naturally occurring plant-produced volatiles by the use of gas chromatography linked to electrophysiology. Volatiles of host as well as non-host plants collected by headspace techniques were used for stimulating the neurones, sequentially via two columns, one polar and one nonpolar installed in parallel in the gas chromatograph. Three types of neurones presented in this paper responded to one, two or three compounds for which the retention times were determined in both column types. The chemical structures of the active components were determined on the basis of mass spectrometry linked to gas chromatography, indicating E-β-ocimene and β-myrcene as stimulants for neurone type 1, E,E-α-farnesene for neurone type 2 and homo-farnesene for neurone type 3. Re-testing authentic materials verified the identifications for the type 1 neurones. The results demonstrate a high specificity for the three types of neurones by strong responses to one or two structurally similar compounds out of hundreds present in a large variety of plants. The study exemplifies plant odour detection by narrowly tuned receptor neurones in a polyphagous moth species.