02405nas a2200253   4500008004100000245008600041210006900127260015500196300001400351490000700365520146600372653001801838653001501856653001801871653001501889653001401904653002001918653002201938653003501960100001501995700002402010700002002034856009702054       2004                        eng d00aEssential oil polymorphism of Thymus praecox subsp. arcticus on the British Isles0 aEssential oil polymorphism of Thymus praecox subsp arcticus on t  aAffiliation: Abt. Pharmazeut. Biol. Mikrobiol., Institut für Pharmazie, Universität Hamburg, Bundesstrasse 45, D-20146 Hamburg, Germanyc2004/04//  a409 - 4210 v323 aThe essential oils of 732 individual plants of Thymus praecox Opiz subsp. arcticus (E. Durand) Jalas (syn. T. drucei Ronn.) collected in Scotland, Ireland, and in the south of England have been analysed by gas chromatography (GC) and mass spectrometry (GC-MS) in order to elucidate the chemical character of this subspecies on the British Isles. In total, 69 components were identified, most of them monoterpenoids and sesquiterpenoids with hedycaryol, linalyl acetate, linalool, the germacradienols, trans-nerolidol, T-cadinol, and β-caryophyllene being the most important compounds. The analysis of the quantitative essential oil data by means of neural networks revealed that T. praecox subsp. arcticus growing in Britain is highly polymorphous. There were 17 chemotypes with the hedycaryol chemotype as the most frequent (24% of the plants), followed by the linalool/linalyl acetate chemotype (22% of the plants) and germacra-1(10),4-dien-6-ol chemotype (18% of the plants). It seems that each part of the British Isles has its special chemotype pattern with 13 chemotypes in Scotland, 11 in Ireland, and 17 in the south of England. An overview of the North Atlantic region of Europe revealed that the polymorphism of T. praecox subsp. arcticus in the essential oil is more distinctive in the southern than in the northern regions, with only 2, 5, and 1 chemotypes in Greenland, Iceland, and Norway, respectively. © 2004 Elsevier Ltd. All rights reserved.10aBritish Isles10aChemotypes10aEssential oil10aHedycaryol10aLamiaceae10alinalyl acetate10aNeuronal networks10aThymus praecox subsp. arcticus1 aSchmidt, A1 aBischof-Deichnik, C1 aStahl-Biskup, E  uhttp://www.scopus.com/scopus/inward/record.url?eid=2-s2.0-1642372459&partnerID=40&rel=R6.5.002260nas a2200277   4500008004100000245006500041210006100106260026900167300001400436490000700450520121500457653001401672653001501686653003001701653001401731653002401745653001301769653001001782653001101792653002001803100001601823700001601839700001401855700001601869856009701885       1999                        eng d00aThe selection of Thymus vulgaris cultivars to grow in Canada0 aselection of Thymus vulgaris cultivars to grow in Canada  aAffiliation: Horticultural Research Centre, Department of Plant Science, Fac. of Agric. and Food Laval Univ., Qué., G1K 7P4, Canada; Affiliation: Institute of Pharmaceutical Biology, Philipps University of Marburg, Deutschhauserstr. 17A, Germany; Affilic1999///  a337 - 3420 v113 aFive different cultivars of Thymus vulgaris originating from various geographical sources (Canada, Germany, former GDR and Spain) were organically cultivated in the fields in Quebec, Canada. The oils obtained through steam distillation of the dried leaves from each cultivar varied from 1.38% to 2.04%, depending on the cultivar used. The highest oil content was obtained from cv "Madrid" followed by "RH-1" and "Laval-1." More than 95% of the oil, with a total of approximately 22 components were identified in the samples. Oxygenated monoterpenes were the main group of constituents in all cultivars. Cultivar "Laval-1," recently developed in Quebec, "Madrid" from Spain and "RH-1 " from Germany were established to belong to thymol-chemotypes. Cultivar "QDLB" characterized by its content of thymol (approximately 39%), carvacrol (17%) and linalool (3.5%), in the oil, was also found to belong to "thymor-chemotypes, while "RH-2" with carvacrol (40%) was found to be a carvacrol-chemotype. Though none of the cultivars had the desired levels of linalool content, "Laval-1" and "RH-1" were found to be prospective cultivars for field commercial organic cultivation in Canada. © 1999 Allured Publishing Corp.10aCarvacrol10aChemotypes10aEssential oil composition10aLamiaceae10aOrganic cultivation10aP-cymene10aThyme10aThymol10aThymus vulgaris1 aLetchamo, W1 aGosselin, A1 aHoelzl, J1 aMarquard, R  uhttp://www.scopus.com/scopus/inward/record.url?eid=2-s2.0-0347421484&partnerID=40&rel=R6.5.0