bluuebunny/crossref_metadata_2025_split huggingface dataset:
2‐formylmethyl‐2‐methyl‐5‐(1‐hydroxy‐1‐methylethyl)‐tetrahydrofuran: Major volatile product of the water‐mediated oxidative decomposition of citral
Authors: Grein B. , Schmidt G. , Full G. , Winterhalter P. , Schreier P. 
Published: November 2006

AbstractWater‐mediated (pH 3) model experiments were performed with citral (neral/geranial 1a/1b) under oxygen atmosphere. After complete decomposition of 1a/1b and solvent extraction of the products formed, separation into neutral and acid fraction was carried out by bicarbonate treatment. Subsequent HRGC, HRGC–MS, and HRGC–FTIR analyses revealed the occurrence of more than twenty compounds, among them geranic acid in the acid fraction and the 2‐formylmethyl‐2‐methyl‐5‐(1‐hydroxy‐1‐methylethyl)‐tetrahydrofuran diastereomers 3a/3b in the neutral fraction were the major products comprising approximately 15% and 80%, respectively, of the total volatiles formed. The determination of the absolute configuration of 3a/3b and their analytical stereo‐differentiation was achieved by synthesis and chromatography of the (2R) configured diastereomers, starting from (R) (—)‐linalol.
Effects of planting time and mineral fertilization on peppermint (mentha x piperita l.) essential oil composition and its biological activity
Authors: Marotti Mauro , Piccaglia Roberta , Giovanelli Enrico , Deans S. G. , Eaglesham Elisabeth 
Published: November 2006

AbstractEssential oil samples of Mentha x piperita L. (peppermint) were analysed by GC–MS and assayed for their antibacterial, antifungal and antioxidant activities. The steam‐distilled oil samples were obtained from autumn and spring planted crops which were treated with nitrogen and phosphorus fertilizers at different rates. The oil samples from spring planted crops had a significantly higher menthol and lower terpinen‐4‐ol concentrations than those from autumn planted crops. Mineral fertilization seemed to increase the content of menthol in the oil, and decreased that of menthone and β‐caryophyllene. The oil samples showed a different degree of inhibition against the twenty‐five microorganisms tested. Some differences were found between the oil samples from autumn and spring planted crops, the former being more active against some microorganisms, and the oil samples from fertilized peppermint seemed to be, on the whole, slightly more effective. Peppermint oil exhibited a marked antifungal activity against Aspergillus niger.
Chiral gc analysis of menthone and isomenthone with high enantiomeric purities in laboratory‐made and commercial essential oils
Authors: Ravid Uzi , Putievsky Eli , Katzir Irena 
Published: November 2006

AbstractDirect separation of the enantiomers of the two diastereomers, menthone and isomenthone, was performed using an octakis‐(3‐O‐butyryl‐2,6‐di‐O‐pentyl)‐α‐cyclodextrin phase. Enantiomerically pure (—)‐menthone and (+)‐isomenthone were detected in many oils of Mentha, Micromeria fruticosa (L.) Druce and Calamintha incána (Sm.) Heldr. High enantiomeric purities of (+)‐menthone and (—)‐isomenthone were detected in commercial and freshly distilled geranium oils.
Volatile constituents of brazilian phoebe oil
Authors: Weyerstahl Peter , Wahlburg Hans‐Christian , Splittgerber Ute , Marschall Helga 
Published: November 2006

AbstractFrom Brazilian Phoebe oil (essential oil of Phoebe porosa Mez. syn. Oreodaphne porosa Mez.) over 100 constituents could be identified by 1H‐NMR spectra and GC–MS. The main constituents are carquejyl acetate (24, 2.1%), the sesquiterpenes α‐copaene (29, 5.6%), γ‐ (56, 3.5%), and δ‐cadinene (59, 3.1%), cremoligenol(88, 8.4%), β‐eudesmol (95, 8.4%), valerianol (97, ˜5%), α‐bisabolol (102, 3.6%) and β‐bisabolol (100, 2.9%). The structures of epi‐sesquithujene (31) and of some trace constituents, oreodaphnenol (50, a 6,8‐cycloguaian‐4‐ol) as well as the rare trans‐α‐bergamot‐2‐en‐10‐one (69) and a new sesquiterpene ketone, porosadienone (99, an 6(7→8)‐abeo‐eudesmadienone), could be confirmed by spectral data.
Volatile components of heteromorpha trifoliata (wendl.) eckl. & zey
Authors: Mwangi J. W. , Achola K. J. , Lwande W. , Hassanali A. , Laurent R. 
Published: November 2006

AbstractThe essential oil isolated by hydrodistillation from Heteromorpha trifoliata (Wendl.) Eckl. & Zey. was analysed by GC and GC‐MS. Sixty compounds constituting about 96% of the oil were identified. The major constituents were α‐pinene (22.2%), germacrene‐D (17.9%) and sabinene (12.3%).
Influencing the level of glycosidically bound volatiles by feeding experiments with a mentha × piperita l. Cultivar
Authors: Stengele M. , Stahl‐Biskup E. 
Published: November 2006

AbstractThe metabolism of menthone in Mentha × piperita L. has been of interest since it has been considered the key to further metabolism of the essential oil in menthone‐rich M. ×piperita. In the present paper we report on results obtained by feeding experiments with M. × piperita L. cv. Black Mitcham containing menthyl glucoside as the main glycosidically bound monoterpene. Following the pattern of the tracer studies carried out by Croteau and co‐workers, pieces of leaves obtained from outdoor peppermint plants were incubated with menthone for seven hours. An increase from 3.8% to 31.5% for menthol and from traces to 1.3% for neomenthol in the aglycone fraction resulted, which means that the main portion of the exogenous precursor menthone was converted into a menthyl glycoside. This is inconsistent with the highly specific menthone metabolism postulated by Croteau and co‐workers, who found neomenthyl glucoside to be the only metabolite.
Oakmoss impact volatiles generated by a basidiomycete of the genus polyporus
Authors: Abraham B. , Berger R. G. , Schulz H. 
Published: November 2006

AbstractA Polyporus sp. generated characteristic oakmoss flavour components such as methyl 2,4‐dihydroxy‐3,6‐dimethyl benzoate (evernyl, methyl β‐orcinate), 2‐hydroxy‐4‐methoxy‐6‐methyl benzoic acid (everninic acid), 3‐hydroxy‐5‐methyl phenol (orcinol) and 3‐methoxy‐2,5‐dimethyl phenol (β‐orcine monomethylether) when grown in submerged culture. Volatile compounds were isolated from the culture medium by solvent extraction and an adsorption technique. Gas chromatographic methods and, because certain compounds were not sufficiently volatile or too unstable at elevated temperatures, a specially developed HPLC method were applied to characterize the fungal metabolites. As well as oakmoss components, the Polyporus sp. produced many other volatiles, such as the sesquiterpene 7β‐hydroxydihydrodrimenin, phenolics, and aliphatic alcohols.
Chiral gc analysis of enantiomerically pure (r)(—)‐linalyl acetate in some lamiaceae, myrtle and petitgrain essential oils
Authors: Ravid Uzi , Putievsky Eli , Katzir Irena 
Published: November 2006

AbstractEnantiomerically pure (R)(—)‐linalyl acetate was detected in the essential oils of Salvia sclarea L. (clary sage), Salvia dominica L., Mentha citrata Ehrh., Myrtus communis L. (myrtle) and Citrus aurantium L. (petitgrain) using Lipodex E as a chiral capillary column.
C13‐Norisoprenoid glycosides in plant tissues: An overview on their occurrence, composition and role as flavour precursors
Authors: Winterhalter Peter , Schreier Peter 
Published: November 2006

AbstractThis review brings up to date the research that has been undertaken on thirteen carbon (C13) norisoprenoid glycosides in plant tissues. Emphasis is on data concerning their occurrence, chemical composition, and reactivity. In particular, their important role as flavour precursors is discussed.
Volatile leaf oils of some south‐western and Southern Australian species of the genus eucalyptus. Part III1—subgenus symphyomyrtus, section bisectaria, series macrocarpae
Authors: Bignell C. M. , Dunlop P. J. , Brophy J. J. , Jackson J. F. 
Published: November 2006

AbstractThe volatile leaf oils of Eucalyptus lane‐poolei Maiden, E. drummondii Benth., E. annuliformis Grayling & Brooker, E. oldfieldii F. Muell., E burracoppinensis Maiden & Blakely, E. macrocarpa subsp. macrocarpa Hopper, E. macrocarpa Hook. subsp. elachantha Brooker & Hopper, E. rhodantha Blakely & Steedm., E. carnabyi Blakely & Steedm. ex Blakely, E. pyriformis Turcz., E. youngiana F. Muell., E. pachyphylla F. Muell., E. kingsmillii (Maiden) Maiden & Blakely, E. leptopoda Benth., E. synandra M. D. Crisp, E. oxymitra Blakely and E. sessilis (Maiden) Maiden & Blakely, isolated by vacuum distillation, were analysed by GC‐MS. Most species contained α‐pinene (5–28%), 1,8‐cineole (0.5–70%), p‐cymene (0.4–12%), aromadendrene (0.8–21%) and bicyclogermacrene (0.1–25%) as principal leaf oil components.
Aromatic plants of tropical central Africa. Part XIX. Volatile components from leaves of two lamiaceae from Cameroon: leucas deflexa hook and Solenostemon monostachyus (P.Beauv.) Briq.
Authors: Mvé‐Mba C. Eyele , Menut C. , Lamaty G. , Zollo P. H. Amvam , Tchoumbougnang F. , Bessière J. M. 
Published: November 2006

AbstractThe chemical composition of the essential oils isolated by hydrodistillation from leaves of Leucas deflexa Hook and of Solenostemon monostachyus (P.Beauv.) Briq. grown in Cameroon, has been investigated by GC and GC‐MS. The leaf essential oil of L. deflexa was characterized by a high amount of sesquiterpene hydrocarbons (80.3%), germacrene‐D (27.8%), β‐caryophyllene (24.1%) and α‐humulene (9.9%) being the major components. The leaf essential oil of S. monostachyus was more complex; β‐pinene (13.0%), oct‐1‐en‐3‐ol (12.6%), β‐caryophyllene (6.9%), octan‐3‐ol (6.8%) and (E,E)‐α‐farnesene (6.2%) were the most abundant constituents.
Constituents of the essential oil of myrtus communis L. from Iran
Authors: Weyerstahl Peter , Marschall Helga , Rustaiyan Abdolhossein 
Published: November 2006

AbstractThe main constituents of the essential oil from Myrtus communis L. from Iran are the monoterpenes α‐pinene (35%), 1,8‐cineole (28%), limonene (11%), linalol (9%), α‐terpineol (5%), and linalyl acetate (2%). In the distillation residue of the oil some trace constituents were identified: 3,3,5,5,8,8‐hexamethyl‐7‐oxabicyclo[4,3.0] non‐1(6)‐ene‐2,4‐dione (1), the 4‐isobutyl‐ (2) and 4‐isobutenyl‐5‐acetoxy‐4‐hydroxy‐2,2,6,6‐tetramethylcyclohexan‐1,3‐dione (3), 4‐acetoxy‐3‐hydroxy‐3‐senecioyl‐2,2,5,5‐tetramethylcyclopentan‐1‐one (4), the known peroxide 5 (G3), and, obviously as artefacts, the (Z)‐ and (E)‐4‐(2‐hydroxy‐2‐methylpropylidene)‐2,2,5,5‐tetramethylcyclopentan‐l,3‐dione (6). The structures of the compounds 1–6 were confirmed by their 1H‐ and 13C‐NMR spectra.
A comparative study of the essential oils of five piper species from Peninsular Malaysia
Authors: Jantan Ibrahim Bin , Ahmad Abdul Rashih , Ahmad Abu Said , Ali Nor Azah Mohd 
Published: November 2006

AbstractThe chemical composition of the leaf oils of five Malaysian Piper species (P. aduncum L., P. lanatum Roxb., P. pedicellosum Wall., P. penangense C.DC. and P. betle L.) was determined by co‐chromatography with authentic samples on two columns of different polarity, GC‐MS and Kováts retention indices. Dillapiole at 64.5% was the most abundant component in the oil of P. aduncum. Chavibetol constituted 69.0% and 42.7% of the oils of P. betle and P. lanatum respectively. The major components of the oil of P. pedicellosum were β‐phellandrene (21.9%) and eugenol (17.2%. )E)‐Nerolidol (17.5%) and cedrol (14.8%) were found to be the major constituents of P. penangense.
Volatiles of an alcoholic extract of flowers from plumeria rubra L. var. acutifolia
Authors: Pino Jorge A. , Ferrer Austreberta , Alvarez Dania , Rosado Aristides 
Published: November 2006

AbstractVolatile compounds of an alcoholic extract from flowers of Plumeria rubra L. var acutifolia were isolated by continuous liquid‐liquid extraction with isopentane. The extract was analysed by HRGC and GC‐MS techniques. A total of 27 compounds were identified, of which 16 are reported for the first time in this flower.
Seasonal variation in essential oil yield and composition from naturalized thymus vulgaris L. in New Zealand
Authors: McGimpsey Jennifer A. , Douglas Malcolm H. , Van Klink John W. , Beauregard Daniel A. , Perry Nigel B. 
Published: November 2006

AbstractThe seasonal variation in essential oil yield and composition from naturalized Thymus vulgaris L. in Central Otago, New Zealand, is reported. Essential oil yield (l/ha), from replicated, pilot‐scale distillations, was influenced by both the field production of herb and the essential oil content of the herb. The oil yield peaked at 22.8 l/ha in December, after flowering had finished. Essential oil composition also varied significantly during the 13‐month sampling period. Levels of the phenolic components, thymol and carvacrol, peaked at a total of 37% after flowering in summer (December and January). p‐Cymene was an important component of Central Otago thyme oils and ranged from 40% to 50% in winter and early spring (May to October), declining to 21% in January. To maximize yields and phenol content of the oil, naturalized thyme in Central Otago should be harvested after flowering has finished in December.
Determination of potent odourants in roasted coffee by stable isotope dilution assays
Authors: Semmelroch P. , Laskawy G. , Blank I. , Grosch W. 
Published: November 2006

AbstractStable isotope dilution assays were developed for 14 important odourants of roasted coffee. The following amounts (mg/kg) were found in the Arabica (I) and the Robusta (II) coffees: 2‐furfurylthiol (1.08 I, 1.73 II), methional (0.24 I, 0.095 II), 3‐mercapto‐3‐methylbutyl formate (0.13 I, 0.115 II), 2‐ethyl‐3‐5‐dimethylpyrazine (0.33 I, 0.94 II), 2,3‐diethyl‐5‐methylpyrazine (0.095 I, 0.31 II), guaiacol (4.2 I, 28.2 II), 4‐vinylguaiacol (64.8 I, 177.7 II), 4‐ethylguaiacol (1.63 I, 18.1 II), vanillin (4.8 I, 16.1 II), (E)‐β‐damascenone (0.195 I, 0.205 II), 4‐hydroxy‐2,5‐dimethyl‐3(2H)‐furanone (109 I, 57 II), 3‐hydroxy‐4,5‐dimethyl‐2(5H)‐furanone (1.47 I, 0.63 II), 5‐ethyl‐3‐hydroxy‐4‐methyl‐2(5H)‐furanone (0.16 I, 0.085 II), 5‐ethyl‐4‐hydroxy‐2‐methyl‐3(2H)‐furanone (17.3 I, 14.3 II).
Automated HPLC‐HRGC: A powerful method for essential oils analysis. Part V. identification of terpene hydrocarbons of bergamot, lemon, mandarin, sweet orange, bitter orange, grapefruit, clementine and mexican lime oils by coupled HPLC‐HRGC‐MS(ITD)
Authors: Mondello Luigi , Dugo Paola , Bartle Keith D. , Dugo Giovanni , Cotroneo Antonella 
Published: November 2006

AbstractA fully automated HPLC‐HRGC‐MS(ITD) system was used for the analysis of the terpene hydrocarbon fraction of eight essential oils: bergamot, lemon, mandarin, sweet orange, bitter orange, grapefruit, clementine and Mexican lime. The system allows the isolation by LC of the hydrocarbon fraction followed by transfer into the GC and identification of the single components by MS(ITD).LC‐GC‐MS coupling gives more accurate results than those obtained from GC‐MS analysis of the whole essential oil. The results obtained were compared with those reported in the literature, and represent a reference for the characterization of the citrus essential oils.
Composition of the essential oil of Minthostachys spicata (Benth.) Epl
Authors: Senatore Felice 
Published: November 2006

AbstractThe essential oil of Minthostachys spicata (Benth.) Epl. was obtained by hydrodistillation from aerial parts of the plant in a 0.53% yield related to the dry weight. The composition of the oil was analysed by gas chromatography and gas chromatography‐mass spectrometry. The oil was found to contain 54.7% oxygenated monoterpenes, the major compounds being menthone (14.5%), 2‐hydroxy‐p‐menth‐1‐en‐3‐one (12.5%) and pulegone (9.7%). Spathulenol (4.9%) was the principal oxygenated sesquiterpene. There were few monoterpene hydrocarbons (3.2%) with limonene as the main component of this fraction. β‐Caryophyllene (4.9%) and viridiflorene (3.5%) were the most abundant sesquiterpene hydrocarbons.
Comparison between green and black pepper oils from Piper nigrum L. Berries of Indian and Sri Lankan origin
Authors: McCarron M. , Mills Allen , Whittaker D. , Kurian Thomas , Verghese J. 
Published: November 2006

AbstractEssential oils obtained by hydrodistillation of green and black Piper nigrum L. berries of Indian origin were analysed by GC and GC‐MS methods and compared with reported constituents of Sri Lankan green and black pepper oils. The monoterpene hydrocarbons of Indian oils are similar to those of corresponding Sri Lankan oils but the oils differ in the make‐up of their sesquiterpene and oxygenated components. β‐Pinene and caryophyllene occur in all oils, sabinene in Sri Lankan oils only and car‐3‐ene in none of the oils. Salzer's recommendation that the ratio of (sabinene + β‐pinene + car‐3‐ene)/caryophyllene ‘as a suitable pepper oil characteristic’ requires further scrutiny.
Deterpenation of sweet orange and lemon essential oils with supercritical carbon dioxide using silica gel as an adsorbent
Authors: Dugo Paola , Mondello Luigi , Bartle Keith D. , Clifford Anthony A. , Breen David G. P. A. , Dugo Giovanni 
Published: November 2006

AbstractA method to deterpenate sweet orange and lemon oils by supercritical fluid extraction (SFE) with carbon dioxide combined with use of silica gel as adsorbent is described. The composition of the oxygenated fractions obtained by SFE was compared to that of deterpenated oils obtained by vacuum distillation, and to that of cold‐pressed oils. The deterpenated products obtained by SFE show qualitative composition and quantitative ratios between oxygenated compounds near to those of original oils.
Aromatic plants of tropical central Africa. Part XVII. 6,7‐epoxymyrcene, the major unusual constituent of Lippia multiflora s.l. moldenke essential oil from the central African Republic
Authors: Menut C. , Lamaty G. , Bessière J. M. , Koudou J. , Maidou J. 
Published: November 2006

AbstractThe essential oil obtained by hydrodistillation from leaves of Lippia multiflora s.l. Moldenke growing in Central African Republic has been analysed by GC and GC‐MS; its chemical composition is rather atypical in that it contains more than 70% of a rare monoterpenoid compound, 6,7‐epoxymyrcene. As far as we know, it is the first time that this compound has been found in an essential oil at such a high level.
Composition of the Essential Oil of Lavandula pinnata L. fil. var. pinnata grown on madeira
Authors: Cristina Figueiredo A. , Barroso José G. , Pedro Luis G. , Sevinate‐Pinto Isabel , Antunes Teresa , Fontinha Susana S. , Looman Anja , Scheffer Johannes J. C. 
Published: November 2006

AbstractThe composition of the essential oils from different aerial parts of Lavandula pinnata L. fil. var. pinnata was analysed by GC and GC‐MS. The oils were isolated separately from flowering tops, and from leaves and stems collected during the flowering period and the vegetative phase of the plant. The three oil samples consisted mainly of monoterpene hydrocarbons (37‐80%), whereas oxygen‐containing monoterpenes were hardly present (2‐4%). β‐Phellandrene (12‐32%) was the main component of the oils analysed, and α‐phellandrene (6‐l6%) the second most important monoterpene. The sesquiterpene fraction of the oils (13‐22%) was also characterized by hydrocarbons of which β‐caryophyllene (11% of each oil) formed the major part. Phenylacetaldehyde amounted to 6‐9% of the leaf oils. Common major components of lavender oils were not found in the oils or were present in very small amounts only.
Aromatic plants of tropical Central Africa. Part XX. The occurrence of 1‐phenylhepta‐1,3,5‐triyne in the essential oil of Bidens pilosa L. from cameroon
Authors: Amvam Zollo P. H. , Kuiaté J. R. , Menut C. , Lamaty G. , Bessiére J. M. , Chalchat J. C. , Garry R. Ph. 
Published: November 2006

AbstractFour essential oil samples were obtained by hydrodistillation from leaves of Bidens pilosa L. collected in Cameroon. Two types of commercially available apparatus were used. The samples were analysed by GC and GC‐MS. The major sesquiterpenes, germacrene‐D and β‐caryophyllene (respectively 21.2‐27.1% and 13.4‐19.8%) were accompanied by 1‐phenylhepta‐1,3,5‐triyne (12.0‐32.3%). The chemotaxonomic implications of the constant presence of small amounts of 7‐methoxy‐2,2‐dimethyl chromene (precocene I), and the influence of the hydrodistillation method on the quantitative chemical composition of the essential oils are discussed.
Kinetics of microwave extraction of rosemary leaves in hexane, ethanol and a hexane + ethanol mixture
Authors: Chen Sau Soon , Spiro Michael 
Published: November 2006

AbstractExtraction experiments were carried out at atmospheric pressure in an electrically and mechanically modified domestic microwave oven, with temperature changes monitored by a gas thermometer. The rates of extraction were measured of six essential oil components of rosemary (Rosmarinus oficinalis L.) and detailed results are given for α‐pinene and for 1,8‐cineole. Major differences of behaviour were found according to whether the solvent employed was hexane, ethanol, or a mixture of 10 mol% hexane + 90 mol% ethanol. Simulated microwave extraction plots generated from the data of a series of thermostatted solvent extractions showed faster extraction rates than expected from the temperature changes. The rates of extractions were affected by the intensity of the microwave energy, the dielectric properties, size and composition of the workload, and the shape of the extracting vessel. Scanning electron micrographs showed that the kinetics and mechanism of the extractions were related to structural changes in the oil‐containing glands.
Analysis of the essential oils of some Agastache species grown in Scotland from various seed sources
Authors: Svoboda K. P. , Gough J. , Hampson J. , Galambosi B. 
Published: November 2006

AbstractThe essential oils obtained by hydrodistillation from plants grown from 25 batches of seed of Agastuche species were investigated. Oil yield and composition were determined from individual samples. The changes in yield and chemical composition were monitored throughout the season. The authenticity of plants was assessed.
Composition of the root essential oils of several Geum species and related members of the subtribus geinae (rosaceae)
Authors: Vollmann C. , Scbultze W. 
Published: November 2006

AbstractThe root essential oils of several members of the genera Geum, Waldsteinia and Coluria, together representing the subtribus Geinae, were analysed by GC‐MS. The qualitative composition of these oils was relatively similar with eugenol and some pinane derivatives, e.g. myrtanals, myrtenal, myrtanols and myrtenol, as characteristic constituents. The oils differed considerably concerning the quantitative composition, e.g. two groups of Geum species could be observed, one with a high (>65%) and one with a low (<5%) content of eugenol. In the root oil of Waldsteinia ternata Fritsch, only traces of this phenylpropanoid were found. Headspace analysis of a root extract of W. geoides Willd. showed a high percentage of cinnamyl alcohol.
Comparison of sesquiterpenes from field collected material and in vitro cultures of Jamesoniella autumnalis (DC.) Steph.
Authors: Becker Hans , Blechschmidt Martin 
Published: November 2006

AbstractTwo new cultures from the liverwort Jamesoniella autumnalis (DC.) Steph. collected at two different natural habitats, were initiated. Fresh weight increase was about eightfold within 80 days. Anastreptene 1, β‐barbatene 2, bicyclogermacrene 3, β‐bisabolene 4, α‐bisabolene 5, spathulenol 6 and 3α‐acetoxybicyclogermacrene 7 were isolated from field collected material as well as from the in vitro cultures. The sesquiterpenoid pattern was compared, and it was found that in vitro cultures had almost the same composition—qualitatively and quantitatively—as the respective material from the natural habitats.