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Volatile Constituents (volatile + constituent)
Selected AbstractsFrom the Linden Flower to Linden Honey , Volatile Constituents of Linden Nectar, the Extract of Bee-Stomach and Ripe HoneyCHEMISTRY & BIODIVERSITY, Issue 12 2004Regula Naef Honey is produced by honeybees (Apis mellifera), which collect nectar from flowers, digest it in their bodies, and deposit it in honeycombs, where it develops into ripe honey. We studied the evolution of the volatile constituents from the nectar of linden blossoms (Tilia cordata) to honey via the ,intermediate' honeybee. The sampling of the contents of the honey stomach or honey sack of the bee is unique. Extracts were prepared from nectar, from the liquid of the honey stomach, and from ripe honey. The chemistry is extremely complex, and compounds spanning from monoterpenes (hydrocarbons, ethers, aldehydes, acids, and bifunctional derivatives), isoprenoids, aromatic compounds (phenylpropanoids, phenols), and products degraded from fatty acids to alkaloids, were identified. Some compounds definitely stem from the plants, whereas other interesting constituents can be attributed to animal origin. Two derivatives of decanoic acid, 9-oxodec-2-enoic acid (12) and 9-hydroxydec-2-enoic acid, identified in the honey are known to be constituents of the so-called ,Queen's pheromone'. Two metabolites of these acids were identified in the extract of the honey stomach: 8-oxononanal (10), a new natural product, and 8-oxononanol (11). There structures were confirmed by synthesis. Nectar and honey stomach contain many aldehydes, which, due to the highly oxidative atmosphere in the honeycomb, are found as corresponding acids in the honey. Two acids were newly identified as 4-isopropenylcyclohexa-1,3-diene-1-carboxylic acid (14) and 4-(1-hydroxy-1-methylethyl)-cyclohexa-1,3-diene-1-carboxylic acid (15). [source] Volatile constituents of Dorema aucheri Boiss., Seseli libanotis (L.) W. D. Koch var. armeniacum Bordz. and Conium maculatum L. three Umbelliferae herbs growing wild in IranFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2006Shiva Masoudi Abstract The composition of the essential oils from three Umbelliferae species of Iran,Dorema aucheri Boiss., which is endemic to Iran, Seseli libanotis (L.) W. D. Koch var. armeniacum Bordz. and Conium maculatum L.,obtained by hydrodistillation were analyzed by GC and GC[sol ]MS. , -Eudesmol (31.2%) and , -cadinene (10.9%) were the main components among the 35 constituents characterized in Dorema aucheri, representing 89.2% of the total components detected. Twenty-five compound were identified in the oil of Seseli libanotis, repesenting 90.6% of the total oil with acorenone (35.5%) as the major constituents. The oil of Conium maculatum was characterized by higher amount of germacrene D (46.1%), , -caryophyllene (15.3%) and (E,E)- , -farnesene (10.1%) among the 17 components comprising 91.0% of the total oil detected. All oils were richer in sesquiterpenes than monoterpenes. Copyright © 2006 John Wiley & Sons, Ltd. [source] Volatile constituents of Achillea pachycephala, A. oxyodonta and A. biebersteinii from IranFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2006Akbar Esmaeili Abstract The water-distilled essential oils from aerial parts of Achillea pachycephala Rech.f. and Achillea oxyodonta Boiss., which are endemic to Iran, and stems, leaves and flowers of Achillea biebersteinii Afan., were analysed by GC and GC,MS. The oil of A. pachycephala was found to contain 1,8-cineole (27.7%) and camphor (27.4%) as the major constituents. The oil of A. oxyodonta was characterized by higher amounts of 1,8-cineole (38.5%) and artemisia ketone (23.0%). The oils obtained from stems and leaves of A. biebersteinii were rich in camphor (38.1% and 33.7%, respectively) and borneol (22.6% and 20.8%, respectively). The other main component of the stem oil was 1,8-cineole (13.5%). In the flower oil of the plant, camphor (36.3%) and 1,8-cineole (22.3%) were the predominant compounds. All oils were richer in oxygenated monoterpenes. Copyright © 2005 John Wiley & Sons, Ltd. [source] Volatile constituents of the flowerheads of three Echinacea species cultivated in IranFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2006Mohammad Hossein Mirjalili Abstract Three medicinal species of the genus Echinacea (Asteraceae), i.e. E. purpurea, E. pallida and E. angustifolia, were cultivated in the experimental field of the Medicinal Plants and Drugs Research Institute of Shahid Beheshti University (Tehran, Iran). The essential oil of flowerheads of the studied species was isolated by hydrodistillation. The essential oils were analyzed by GC and GC-MS. In total, 36, 30 and 36 constituents were identified and quantified in E. purpurea, E. pallida and E. angustifolia, respectively. Sesquiterpene hydrocarbons were the main group of compounds in E. purpurea (70.9%), E. angustifolia (70%) and E. pallida (62.6%). The content of germacrene-D in E. purpurea (57%) was higher than that in E. pallida (51.4%) and E. angustifolia (49.6%) as the principal component in all samples. Also, the monoterpene hydrocarbons were observed in the oil of E. purpurea (6.4%) and E. angustifolia (1.2%), while these compounds were completely absent in E. pallida oil. Copyright © 2006 John Wiley & Sons, Ltd. [source] Volatile constituents of essential oils isolated at different growth stages from three Conyza species growing in GreeceFLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2005O. Tzakou Abstract The essential oils isolated at vegetative, flowering and flowering,fruiting stages of three Conyza species growing in Greece were analysed by GC,MS; 54 constituents were identified. The oils of C. albida were rich in limonene (10.0,21.1%), germacrene D (10.5,20.2%) and cis -lachnophyllum ester (8.8,36.5%). The oils of C. bonariensis were rich in limonene (8.3,15.1%), (E)- , -ocimene (11.5,18.9%), cis -lachnophyllum ester (10.8,21.2%) and matricaria ester (9.4,17.5%). The oils of C. canadensis were rich in limonene (50.0,70.3%) and (E)- , -ocimene (4.0,7.5%). The oils showed significant variations among the growth stages. These variations can be used for distinguishing the three species. Copyright © 2005 John Wiley & Sons, Ltd. [source] Volatile constituents of the flowers of Clerodendron fragrans (Vent.) R. Br.FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2005K. C. Wong Abstract The volatile constituents of Clerodendron fragrans (Vent.) R. Br. flowers were analysed by capillary GC and GC,MS following isolation by hydrodistillation,extraction; 41 compounds were identified. Oxygenated monoterpenes and aromatic compounds originating from phenylpropanoid metabolism predominated, accounting for 41.2% and 36.0% respectively, of the total volatiles. The major components were linalol, benzyl acetate and benzyl benzoate. Copyright © 2005 John Wiley & Sons, Ltd. [source] Volatile constituents of the cold desert plant Dracocephalum heterophyllum Benth. ,FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005U. Mahmood Abstract The essential oil of Dracocephalum heterophyllum Benth. (Lamiaceae) from wild and cultivated plants was obtained by hydrodistillation and analysed by GC and GC,MS techniques. Twelve constituents, accounting for 96.8% of the total oil from wild plants, and nineteen constituents, accounting for 99.9% of the total oil from cultivated plants, were identified. Citronellol was identified as one of the major constituents, attaining 74.9% in the wild and 54.3% in the cultivated population, respectively. This plant was found to be a new source of citronellol and rose oxides, which are mostly used in the essential oil and perfumery industry. Copyright © 2005 John Wiley & Sons, Ltd. [source] Volatile constituents of the essential oil of Nepeta ucrainica L. ssp. kopetdaghensis from IranFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005K. Javidnia Abstract Composition of the volatile oil of Nepeta ucraininca L. ssp. kopetdaghensis (Lamiaceae) was investigated by GLC and GC-MS. Forty-one compounds representing 89.5% of the total oil were characterized. The main components of the oil were germacrene-D (39.7%), palmitic acid (10.8%), , -bourbonene (5.8%) and spathulenol (5.6%). Nepetalact-one isomers were not present in the essential oil of N. ucrainica L. ssp. kopetdaghensis. Copyright © 2004 John Wiley & Sons, Ltd. [source] Volatile constituents of different organs of Psoralea bituminosa L.FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2004Alessandra Bertoli Abstract The essential oil and SPME samples of the leaves, ,owers and seeds of Psoralea bituminosa L. were analysed by GC and GC,MS. We have investigated also the presence of monoterpene or aliphatic alcohol glucosides. The essential oils showed both qualitative and quantitative differences. The main constituents of the leaf and the ,ower essential oils were caryophyllene (23% and 18%, respectively), , -farnesene (15% and 6%, respectively), and germacrene D (24% and 18%, respectively). Signi,cant amounts (7%) of the same compounds were also directed in the seed essential oil, but tricyclene (11%) and , -pinene (50%) were the most important constituents of this oil. The volatile fractions of remaining leaf aqueous extracts after treatment with , -glucosidase revealed qualitative differences in comparison with the composition of the corresponding essential oils, and high levels of 3-hexen-1-ol (37%) and 1-octen-3-ol (27%) were observed. The SPME analysis of the fresh leaves, ,owers and seeds of P. bituminosa con,rmed the qualitative composition of the volatile oils, even if we detected signi,cative differences in the percentage ratio between monoterpenes and sesquiterpenes in comparison with the oils, where sesquiterpenes were the main components. In fact the variation of the monoterpenes, tricyclene, , -pinene and camphene between the leaf oil and the corresponding headspace sample was remarkable: tricyclene increased from 0.1% to 8%, , -pinene from 0.1% to 16% and camphene from 0.3% to 10% in the SPME samples. Copyright © 2004 John Wiley & Sons, Ltd. [source] Volatile constituents of fruits of Garcinia dulcis Kurz. from CubaFLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2003Jorge Pino Abstract The volatile constituents of rata fruits (Garcinia dulcis Kurz.) growing in Cuba were analysed by GC,MS. Ninety compounds were identi,ed in the aroma concentrate, of which linalool, , -terpineol and hexadecanoic acid were found to be the major constituents. Copyright © 2003 John Wiley & Sons, Ltd. [source] Volatile constituents of benzoin gums: Siam and Sumatra.FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2003Part Abstract The volatile extract composition of two different benzoin gums, Siam and Sumatra, were analysed by GC,MS. Twenty components representing more than 99.1% of the oil from Siam and 29 components representing more than 97.4% of the oil from Sumatra were analysed. The major components were benzyl benzoate (76.1,80.1%) for the two oils and benzoic acid (12.5%), methyl benzoate (1.5%) and allyl benzoate (1.5%) for Siam, and styrene (2.3%), cinnamic acid (3.5%) and benzyl cinnamate (3.3%) for Sumatra. Volatile compounds of oils and crushed benzoins were also studied using solid-phase microextraction (SPME) employing carboxen/polydimethylsiloxane and carbowax/divinylbenzene ,bres. Copyright © 2003 John Wiley & Sons, Ltd. [source] Volatile constituents of the leaves and flowers of Hypericum triquetrifolium Turra,FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2003Alessandra Bertoli Abstract The ,ower and leaf oil of Hypericum triquetrifolium Turra (Guttiferae, Hypericoideae) from Calabria (Italy) were studied by GC and GC,MS. The major components identi,ed in each oil were n -nonane (8%, 15%), , -pinene (8%, 4%), , -pinene (13%, 10%), myrcene (16%, 5%), , -caryophyllene (5%, 11%), germacrene-D (10%, 13%), sabinene (13%, 3%) and caryophyllene oxide (5%, 12%) in the leaf and ,ower oils, respectively. The aerial parts of the same plant were also analysed by SPME. The SPME analysis showed higher yields of undecane (14%, 10%) and , -caryophyllene (14%, 10%) in comparison with the corresponding hydrodistillation oils, in addition to , -pinene, , -pinene, sabinene and myrcene, amounting to (9%, 6%), (7%, 4%), (1%, 9%), (1%, 10%) for the leaves and ,owers, respectively. Copyright © 2003 John Wiley & Sons, Ltd. [source] Volatile constituents of Vietnamese pummelo, orange, tangerine and lime peel oilsFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2002N. T. Minh Tu Abstract The compositions of Vietnamese pummelo (Citrus grandis Osbeck), orange (C. sinensis Osbeck), tangerine (C. reticulata Blanco var. tangerine) and lime (C. limonia Osbeck) peel oil samples have been investigated by GC and GC,MS. The essential oils were extracted by the cold-pressing method. Hydrocarbons, followed by aldehydes and alcohols, were the most abundant compounds in all four kinds of samples. Their percentages, respectively, were >98.7%, >97.6%, >98.6% and >95.4% in hydrocarbons; >0.3%, 0.4%, >0.3% and 1.1% in total aldehydes; 0.2%, 0.5%, 0.4% and 0.7% in alcohols. In Vietnamese pummelo oil, ,-terpinene was not detected, while terpinolene was detected in small amounts and nootkatone only at a level of <0.05%. Orange oil composition was comparable to that of other sweet orange oils. ,-3-Carene was detected at a level of 0.1%. Tangerine oil is easily distinguished from other citrus oils by its content of various aliphatic aldehydes. Lime oil presented a very different composition from the other oils studied. Its limonene content was substantially lower than that of pummelo, orange and tangerine oils, whereas ,-terpinene, ,-pinene and ,-pinene occurred in higher proportions, moreover, the sesquiterpene hydrocarbon fraction of this oil is qualitatively more complex and quantitatively more abundant than in the other oils. Copyright © 2002 John Wiley & Sons, Ltd. [source] Volatile constituents of Hymenocrater incanus Bunge, an Iranian endemic speciesFLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2001M. Mirza Abstract The volatile constituents of the aerial parts of Hymenocrater incanus Bunge growing in Iran, isolated by hydrodistillation, was analysed by GC,MS. The oil was found to contain 35 components. The oil was rich in ,-caryophyllene (17.6%) and 1,8-cineole (16.9%). The other major constituents were ,-pinene (9.2%), ,-pinene (7%), trans -,-ocimene (5.4%), germacrene-D (4.5%) and caryophyllene oxide (3.9%). Copyright © 2001 John Wiley & Sons, Ltd. [source] The volatile constituents of frankincense , a reviewFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2009Michaela Mertens Abstract The smell of frankincense resin and powder, as well as burned frankincense, has been linked to a series of health effects since ancient times. Additionally, frankincense and its fumes are used as a means to induce positive psychophysical effects and well-being, not only in an ecclesiastical setting but also in traditional medical applications. This review aims to provide an overview of current knowledge of the volatile constituents of frankincense, with explicit consideration concerning the diverse Boswellia varieties. Altogether, more than 300 volatiles in frankincense have been reported in the literature. In particular, a broad diversity has been found in the qualitative and quantitative composition of the volatiles with respect to different varieties of Boswellia. A detailed discussion of the various analytical approaches applied to isolating and analysing the volatile fractions of frankincense is also presented. Copyright © 2009 John Wiley & Sons, Ltd. [source] A selective and sensitive approach to characterize odour-active and volatile constituents in small-scale human milk samplesFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2007Andrea Buettner Abstract A sensitive and selective analytical approach was developed for the characterization of trace volatile and odorous substances in body fluids. The methodology was successfully applied for identification of more than 40 characteristic odorants in human milk. The technique comprises a modified stir bar sorptive extraction system in combination with two-dimensional gas chromatographic separation and parallel mass spectrometric and olfactometric characterization of the analytes. The present study shows that the technique can be used for both direct extractive sampling and headspace analysis, and that it is applicable for small sample volumes. Copyright © 2007 John Wiley & Sons, Ltd. [source] Flavour volatiles of leaves, fruits and seed cotyledons of Murraya koenigii L.FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005S. G. Walde Abstract The flavour volatile constituents of seed cotyledons, fruits and leaves of Murraya koenigii L. (curry leaf plant), grown in Hyderabad, India, were analysed by GC,MS and compared with curry leaf flavour constituents. These consist of monoterpene hydrocarbons, oxygenated monoterpenes and sesquiterpenes. The major constituents of curry leaf are monoterpenes (70%); seed cotyledons (86%), constituting , -pinene (52%) and cis -ß-ocimene (34%); raw fruit oil containing monoterpenes (80%) and oxygenated monoterpenes (4.8%); and fruit pulp oil containing monoterpenes (61%). The present findings constitute the first report of volatile constituents of parts of Murraya koenigii L. other than the leaves. Copyright © 2005 John Wiley & Sons, Ltd. [source] Variation in essential oil composition of rose-scented geranium (Pelargonium sp.) distilled by different distillation techniques,FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005Kiran G. D. Babu Abstract The rose-scented geranium (Pelargonium sp.) cultivar ,Kelkar', grown in the agroclimatic conditions of the western Himalayas, was processed by various hydrodistillation methods, which revealed that water distillation of the herb gave a higher oil yield (0.16,0.22%) than the water,steam distillation (0.09,0.12%) and steam distillation methods (0.06,0.18%). The samples were analysed by GC and GC,MS to study and compare the essential oil compositions which revealed that the oil distilled by the water,steam distillation method contained a higher content of monoterpene hydrocarbons (1.7%), followed by steam distillation without cohobation and without recycling (1.5%). A higher content of sesquiterpene hydrocarbons (4.4%) was found in cumulative oil followed by ,direct oil' (4.2%) obtained by steam distillation with cohobation and without recycling of hydrosol, followed by the water,steam distillation method (3.4%). ,Decanted oil', recovered from redistilling the hydrosol obtained by steam distillation with cohobation and without recycling, contained maximum monoterpene cyclic ethers (1.1%) and carbonyl content (9.9%), closely followed by water,steam distillation method (1.1% and 7.2%, respectively). Steam distillation without cohobation and without recycling of hydrosol yielded essential oil with a higher percentage of esters (21.1%), followed by ,direct oil' (16.6%). Lower ester content (5.3%) was noticed in ,decanted oil', followed by oil distilled by steam distillation with cohobation and with recycling (11.8%) and oil distilled in a Clevenger apparatus by the water distillation method (12.2%), whereas maximum total alcohols were found in the ,decanted oil' (75.1%), followed by oil from the Clevenger apparatus (72.8%) and steam distillation with cohobation and with recycling (69.1%). A lower alcohol content was found in the ,direct oil' (55.2%) closely followed by ,cumulative oil' (55.8%). The variation in total alcohol and ester contents in geranium oil samples, distilled by using different processing techniques on pilot scale distillation, is mainly due to hydrolysis of some volatile constituents. This was further supported by acid values of the oils, along with other physicochemical properties, such as speci,c gravity, optical rotation, refractive index, solubility in alcohol, ester value with cold and hot methods, estimation of ester content as geranyl formate and geranyl tiglate, ester number after acetylation, and ester number after formylation with aceto-formic acid and formic acid. Methods have been standardized and proposed for distillations of speci,c quality, e.g. ester-rich and alcohol-rich geranium oils, to meet different requirements of the industry. Copyright © 2004 John Wiley & Sons, Ltd. [source] Secretory elements of needles and berries of Juniperus communis L. ssp. communis and its volatile constituentsFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2003F. Shahmir Abstract The structure of the secretory elements and the essential oils of the needles and berries of Juniperus communis L. ssp. communis growing in north Iran were studied. The needles, which contain ducts and transfusion tissue, act as conduction structures, and the berries containing elongate tubercles which act as reservoirs of volatile oils. The essential oils, isolated by hydrodistillation, were analysed by GC,MS. The oil contained 41 and 27 components in the needles and berries, respectively. The needle oil consisted mainly of sabinene (40.7%), , -pinene (12.5%) and terpinen-4-ol (12.3%) and the berry oil included sabinene (36.8%), , -pinene (20%), limonene (10.6%), germacrene D (8.2%) and myrcene (4.8%) as the main components. Copyright © 2003 John Wiley & Sons, Ltd. [source] Perfect Bi4Ti3O12 Single-Crystal Films via Flux-Mediated Epitaxy,ADVANCED FUNCTIONAL MATERIALS, Issue 4 2006R. Takahashi Abstract Excellent crystallinity of material films and atomic control of their surface/interface, sufficient for the realization of their optimal physical properties, are technological premises for modern functional-device applications. Bi4Ti3O12 and related compounds attract much interest as highly insulating, ferroelectric materials for use in ferroelectric random-access memories. However, it has been difficult thus far for Bi4Ti3O12 films to satisfy such requirements when formed using vapor-phase epitaxy, owing to the high volatility of Bi in a vacuum. Here, we demonstrate that flux-mediated epitaxy is one of the most promising and widely applicable concepts to overcome this inevitable problem. The key point of this process is the appropriate selection of a multi-component flux system. A combinatorial approach has led to the successful discovery of the novel flux composition of Bi,Cu,O for Bi4Ti3O12 single-crystal film growth. The perfect single-crystal nature of the stoichiometric Bi4Ti3O12 film formed has been verified through its giant grain size and electric properties, equivalent to those of bulk single crystals. This demonstration has broad implications, opening up the possibility of preparing stoichiometric single-crystal oxide films via vapor-phase epitaxy, even if volatile constituents are required. [source] Volatile compounds characterising Tunisian virgin olive oils: the influence of cultivarINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2010Dhouha Krichene Summary In this work, the volatile profiles of four Tunisian virgin olive oils were established by headspace-solid phase microextraction and gas chromatography, using flame ionisation and mass spectrometer detectors. More than eighty compounds were isolated and characterised, representing 97,99% of the total GC area. The main volatile compounds present in the oil samples were determined quantitatively, the major constituents were often aldehydes, particularly (E)-2-hexenal (48,90%). Significant differences in the content of volatile constituents were observed. These quantitative differences were used to distinguish between virgin olive oils from different varieties. [source] MULTIVARIATE ANALYSIS FOR CLASSIFICATION OF COMMERCIAL GRAPEFRUIT JUICE PRODUCTS BY VOLATILE CONSTITUTESJOURNAL OF FOOD QUALITY, Issue 3 2000JORGE A. PINO ABSTRACT Isolation of volatile constituents from fresh and processed grapefruit juice by a simple technique afforded up to 20 components in each juice type. Many of these constituents are known to contribute to grapefruit juice flavor. Multivariate analysis utilizing the concentration data of twelve constituents allowed classification of the juice samples according to processing conditions. The classification corresponded to expected flavor quality. [source] Aroma Components of American Country HamJOURNAL OF FOOD SCIENCE, Issue 1 2008H. Song ABSTRACT:, The aroma-active compounds of American country ham were investigated by using direct solvent extraction-solvent assisted flavor evaporation (DSE-SAFE), dynamic headspace dilution analysis (DHDA), gas chromatography-olfactometry (GCO), aroma extract dilution analysis (AEDA), and gas chromatography-mass spectrometry (GC-MS). The results indicated the involvement of numerous volatile constituents in the aroma of country ham. For DHDA, 38 compounds were identified as major odorants, among them, 1-octen-3-one, 2-acetyl-1-pyrroline, 1-nonen-3-one, decanal, and (E)-2-nonenal were the most predominant, having FD-factors , 125 in all 3 hams examined, followed by 3-methylbutanal, 1-hexen-3-one, octanal, acetic acid, phenylacetaldehyde, and FuraneolÔ. For the DSE-SAFE method, the neutral/basic fraction was dominated by 1-octen-3-one, methional, guaiacol, (E)-4,5-epoxy-(E)-decenal, p-cresol as well as 3-methylbutanal, hexanal, 2-acetyl-1-pyrroline, phenylacetaldehyde, and ,-nonalactone. The acidic fraction contained mainly short-chain volatile acids (3-methylbutanoic acid, butanoic acid, hexanoic acid, and acetic acid) and Maillard reaction products (for example, 4-hydroxy-2,5-dimethyl-3(2H)-furanone). The above compounds identified were derived from lipid oxidation, amino acid degradation, and Maillard/Strecker and associated reactions. Both methods revealed the same nature of the aroma components of American country ham. [source] Comparative aroma profiles using supercritical carbon dioxide and Likens,Nickerson extraction from a commercial brand of Basmati riceJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2003Paramita Bhattacharjee Abstract A comparative evaluation of the extraction of the aroma constituents of a popular commercial brand of Basmati rice using Likens,Nickerson extraction and supercritical fluid extraction (SFE) with carbon dioxide was carried out. SFE at 50 °C and 120 bar for 2 h provided appreciable extraction of the volatile constituents of the rice as compared with Likens,Nickerson extraction. The advantages of smaller sample size, shorter time of extraction and negligible possibility of artefacts with the SFE technique merit its use for recovery of aroma volatiles from Basmati rice. Copyright © 2003 Society of Chemical Industry [source] Sensory and behavioural responses of the stable fly Stomoxys calcitrans to rumen volatilesMEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2007P. JEANBOURQUIN Abstract Analysis of volatiles from rumen digesta by gas chromatography linked antennogram recordings from Stomoxys calcitrans (L) (Diptera: Muscidae) antennal receptor cells revealed about 30 electrophysiologically active constituents, the most important of which is dimethyl trisulphide with a sensory threshold in the femtogram range. The behavioural responses of S. calcitrans to five chemostimulants (dimethyl trisulphide, butanoic acid, p -cresol, oct-1-en-3-ol and skatole) were tested in a wind tunnel where activation and attraction of hungry flies to rumen volatiles were recorded. Dimethyl trisulphide, butanoic acid and p -cresol were found to attract S. calcitrans. This sensitivity to rumen volatile constituents, that also occur in animal wastes used for oviposition by Stomoxys spp., as well as in flowers used by stable flies as sources of nectar is discussed in the context of the behavioural ecology of these flies. [source] Zanthoxylum piperitum (DC), a potential feeding deterrent for mammals: studies with Microtus ochrogaster (Wagner)PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2004Gisela Epple Abstract Total extract from the fruit of Szechuan pepper (Zanthoxylum piperitum DC), the volatile components of the extract and a non-volatile fraction containing alkylamides (NVA fraction) are feeding deterrents for rats. The present study investigated the effectiveness of these natural repellents in prairie voles (Microtus ochrogaster Wagner). Two-choice feeding trials were conducted during which food-deprived voles were offered choices between oat-bran wafers. In Experiment 1, 10 voles were given three sets of feeding trials, each 2 h long. Baseline consumption was established during the first set of two trials by offering a choice between two oat-bran wafers dipped in ethanol, the control solvent. During the second set of two trials the voles were given a choice between an oat-bran wafer dipped in ethanol and a wafer dipped in Zanthoxylum extract. During the third set the voles were given a choice between a wafer served on top of a screened dish containing a sample of ethanol and a wafer served on top of a dish containing a sample of extract. In this manner the voles were exposed to volatile compounds emanating from the extract but could not contact it. Wafers dipped in extract were almost completely avoided. The volatile components of extract also significantly reduced food intake. In Experiment 2, habituation to the volatile constituents of extract was examined in 16 Zanthoxylum -naïve voles. Baseline consumption was established by offering two wafers served on top of screened dishes containing ethanol. This was followed by twelve tests during which a choice between a wafer served above a sample of ethanol and a wafer served above a sample of extract was given. The voles failed to habituate to the volatile components of extract, consistently consuming less of the wafers served above extract. In Experiment 3 a dose-response curve to Zanthoxylum extract was established, using 12 stimulus-naïve voles. After baseline consumption was established, the animals were given two tests each, presenting a choice between a control wafer and a wafer dipped in a dilution of extract (0.001,100 g liter,1). Only concentrations of 10 and 100 g liter,1 reduced food intake. In Experiment 4 the effects of the non-volatile fraction of extract were compared to those of whole extract. Vegetable oil was used as solvent. Eight stimulus-naïve voles were given two tests with a choice between an oil-dipped and an extract-dipped wafer. A second group of eight voles received two tests with a choice between an oil-dipped and NVA-dipped wafer. Extract-dipped wafers were avoided, but the NVA fraction had no effect on food consumption. Copyright © 2004 Society of Chemical Industry [source] Pharmaceutical and therapeutic Potentials of essential oils and their individual volatile constituents: a reviewPHYTOTHERAPY RESEARCH, Issue 4 2007Amr E. Edris Abstract Essential oils and their volatile constituents are used widely to prevent and treat human disease. The possible role and mode of action of these natural products is discussed with regard to the prevention and treatment of cancer, cardiovascular diseases including atherosclerosis and thrombosis, as well as their bioactivity as antibacterial, antiviral, antioxidants and antidiabetic agents. Their application as natural skin penetration enhancers for transdermal drug delivery and the therapeutic properties of essential oils in aroma and massage therapy will also be outlined. Copyright © 2007 John Wiley & Sons, Ltd. [source] From the Linden Flower to Linden Honey , Volatile Constituents of Linden Nectar, the Extract of Bee-Stomach and Ripe HoneyCHEMISTRY & BIODIVERSITY, Issue 12 2004Regula Naef Honey is produced by honeybees (Apis mellifera), which collect nectar from flowers, digest it in their bodies, and deposit it in honeycombs, where it develops into ripe honey. We studied the evolution of the volatile constituents from the nectar of linden blossoms (Tilia cordata) to honey via the ,intermediate' honeybee. The sampling of the contents of the honey stomach or honey sack of the bee is unique. Extracts were prepared from nectar, from the liquid of the honey stomach, and from ripe honey. The chemistry is extremely complex, and compounds spanning from monoterpenes (hydrocarbons, ethers, aldehydes, acids, and bifunctional derivatives), isoprenoids, aromatic compounds (phenylpropanoids, phenols), and products degraded from fatty acids to alkaloids, were identified. Some compounds definitely stem from the plants, whereas other interesting constituents can be attributed to animal origin. Two derivatives of decanoic acid, 9-oxodec-2-enoic acid (12) and 9-hydroxydec-2-enoic acid, identified in the honey are known to be constituents of the so-called ,Queen's pheromone'. Two metabolites of these acids were identified in the extract of the honey stomach: 8-oxononanal (10), a new natural product, and 8-oxononanol (11). There structures were confirmed by synthesis. Nectar and honey stomach contain many aldehydes, which, due to the highly oxidative atmosphere in the honeycomb, are found as corresponding acids in the honey. Two acids were newly identified as 4-isopropenylcyclohexa-1,3-diene-1-carboxylic acid (14) and 4-(1-hydroxy-1-methylethyl)-cyclohexa-1,3-diene-1-carboxylic acid (15). [source] | |||||||||||||