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Chemical Composition (chemical + composition)
Kinds of Chemical Composition Terms modified by Chemical Composition Selected AbstractsEFFECTS OF PROCESS VARIABLE CONDITIONS ON MINERAL AND CHEMICAL COMPOSITION OF EXTRUDED AFRICAN BREADFRUIT (TRECULIA AFRICANA DECNE) MIXTURESJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2009TITUS U. NWABUEZE ABSTRACT Five levels of African breadfruit (Treculia africana), corn and soybean mixtures (fc) in ratios of 40:5:55, 55:5:40, 70:5:25, 85:5:10 and 100:0:0, respectively, were hydrated to 15, 18, 21, 24 and 27% (fm) and extruded at 100, 120, 140, 160 and 180 rpm (ss) in a Brabender single-screw extruder. The objective was to study effects of process variable conditions on mineral and chemical composition of the mixtures. Models developed by response surface analysis were high (R2 = 0.7646,0.9732) for Na, Ca, Mg, protein, fat, fiber and carbohydrate, and showed no significant (P > 0.05) lack of fit. All process variables had significant (P , 0.05) linear effects on Mg, protein and carbohydrate, quadratic effects on fat, energy and Mg and cross-product effects on Ca, Mg, protein and carbohydrate, when fc interacted with either fm or ss. Optimum process variable conditions that gave the best mineral and chemical composition were obtained at 40:5:55(fc), 18% (fm) and 140 rpm (ss). PRACTICAL APPLICATIONS The potentials of African breadfruit as a nutrient resource and its position in the food cycle of the people in the subtropical African countries makes its blending with other local ingredients one important way of expanding the scope of its utilization. African breadfruit seeds provide a delicacy and a specialized meal when consumed alone or with shelled milk-corn. The versatility and acceptance of extrusion as a processing technology and its benefits over conventional methods and worldwide adaptability to a variety of crops, makes its application in this research appropriate. Optimization of process variable conditions affecting mineral and chemical composition of extruded and unextruded mixtures of African breadfruit, corn and soybean, using response surface analysis, was the thrust of the study. It is expected to produce an optimum process combination that could give the best mineral and chemical composition for a possible scale-up operation in African breadfruit seed processing enterprises. [source] THE EFFECTS OF HOT SMOKING ON THE CHEMICAL COMPOSITION AND SHELF LIFE OF MEDITERRANEAN MUSSEL (MYTILUS GALLOPROVINCIALIS L. 1819) UNDER CHILLED STORAGEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2008HÜLYA TURAN ABSTRACT In this study, effects of boiling and hot smoking on proximate composition and shelf life of mussels stored at 4 ± 1C were investigated. Dry matter, crude protein, crude fat and crude ash levels were determined as 13.94, 10.30, 1.14 and 0.95% in fresh mussels 20.75, 13.83, 2.11, 0.77% after boiling and 39.57, 22.22, 10.04%, 6.02% after hot smoking, respectively. Trimethylamine nitrogen values in fresh, boiled and hot smoked mussels were determined as 1.13, 1.01 and 1.07 mg/100 g, respectively, and increased to 24.35 mg/100 g at 18th day of the storage period. pH value in hot smoked mussels ranged between 4.85 and 4.51 during the chilled storage. According to the results, mussels smoked by hot smoking and stored at refrigerator temperature (4 ± 1C) for 12 days can be consumed. PRACTICAL APPLICATIONS In many countries, smoking is used to obtain products that are popular for their texture and flavor. Mussels, scallops and oysters are some of the important mollusk species that are smoked and eaten in different parts of the world. In this research, the effects of hot smoking process (for 30 min at 82C) on proximate composition and shelf life of Mediterranean mussel stored at 4C was investigated. [source] DEEPLY COLOURED AND BLACK GLASS IN THE NORTHERN PROVINCES OF THE ROMAN EMPIRE: DIFFERENCES AND SIMILARITIES IN CHEMICAL COMPOSITION BEFORE AND AFTER ad 150*ARCHAEOMETRY, Issue 5 2009V. VAN DER LINDEN In this work we attempt to elucidate the chronological and geographical origin of deeply coloured and black glass dating between 100 bc and ad 300 on the basis of their major and trace element compositions. Samples from the western and eastern parts of the Roman Empire were analysed. Analytical data were obtained by means of a scanning electron microscope , energy-dispersive system (SEM,EDS, 63 samples analysed) and laser ablation , inductively coupled plasma , mass spectrometry (LA,ICP,MS, 41 samples analysed). Among the glass fragments analysed, dark brown, dark purple and dark green hues could be distinguished. Only among the dark green fragments could a clear compositional distinction be observed between fragments dated to the periods before and after ad 150. In the early samples (first century bc to first century ad), iron, responsible for the green hue, was introduced by using impure sand containing relatively high amounts of Ti. In contrast, a Ti-poor source of iron was employed, containing Sb, Co and Pb in trace quantities, in order to obtain the dark green colour in the later glass samples. The analytical results obtained by combining SEM,EDS and LA,ICP,MS are therefore consistent with a differentiation of glassmaking recipes, detectable in glass composition, occurring in the period around ad 150. [source] Influence of Water Stress on the Chemical Composition of Seeds of Two Lupins (Lupinus albus and Lupinus mutabilis)JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 2 2005I. S. Carvalho Abstract We have performed chemical proximate analysis and determined the carbohydrate profile of mature seeds of Lupinus albus, cv. Rio Maior and Lupinus mutabilis, cv. Potosi plants, either well watered (ww) or subjected to a water-stress period (imposed from the 15th to 35th day after anthesis). Protein content from lupin seeds was 450 and 320 g kg,1 of seed on dry weight basis, for ww plants, respectively, of L. albus and L. mutabilis. Water stress did not affect protein content. The oil content of ww plants was about 120 g kg,1 of seed dry weight for L. albus and 180 g kg,1 of seed dry weight for L. mutabilis. Water stress reduced those values of half. The sugar content was about 90 g kg,1 for L. albus and 50 g kg,1 of seed dry weight for L. mutabilis, in ww plants. Water stress led to an increase in sugar content to 200 and 130 g kg,1 of seed dry weight, respectively, for L. albus and L. mutabilis. The , -galactosides amounted to 70 % of the total sugars (raffinose being 30 % and stachyose, 40 %) and sucrose was about 20 % of the total sugars. Water stress increased total carbohydrates and increased the sucrose/, -galactoside ratio, although reducing raffinose content and increasing sucrose content. [source] The Effects of Plant Population Density on the Growth and Chemical Composition of Lablab purpureus Grown for Fodder Production in a Semi-Arid RegionJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 2 2001Y. Shehu Lablab purpureus was grown in two 6-month field experiments in the Savannah region of Africa, with high rainfall and hot temperatures in the first 2 months, followed by low rainfall and cool temperatures until harvesting in January. The experiments evaluated the effects of plant population density (PPD), using rows at 70-, 110- and 150-cm intervals, on the yield and nutritive value of the crop, and the effect of an interim harvest on response to PPD. Lablab yield ha,1 was increased to a greater extent by an increase in PPD from 110 to 70 cm interrow spacing than by an increase from 150 to 110 cm, and yield plant,1 decreased as PPD increased to a greater extent for double-harvested than for single-harvested plants. This suggested that high PPD in the early stages of growth is important to promote high crop yields in this environment, probably because it mitigates drought effects in autumn. The effects of PPD on herbage composition were small and suggested that plant maturity had not been greatly affected by density. It is concluded that the maintenance of plant cover in the early stages of growth is important for high yields in the Savannah region, which can be achieved by an interrow spacing of no more than 70 cm and avoidance of an interim harvest. Die Einflüsse der Bestandesdichte auf Wachstum und chemische Zusammensetzung von Lablab purpureus im Anbau zur Futterproduktion in einer semiariden Region Lablab purpureus wurde in zwei 6 Monate andauernden Feldexperimenten in der Savannenregion von Afrika angebaut, wobei hoher Regenfall und hohe Temperaturenin den ersten beiden Monaten, gefolgt durch niedrigen Regenfall und kühle Temperatur bis zur Ernte im Januar vorherrschten. Die Experimente wurden im Hinblick auf die Einflüsse der Bestandesdichte (PPD) ausgewertet, wobei Reihenabstände von 70, 110 und 150 cm hinsichtlich des Ertrages und des Nährwertes des Bestandes und des Einflusses auf eine Zwischenernte in Abhängigkeit von PPD untersucht wurden. Der Lablab -Ertrag/ha war stärker durch Zunahmen in PPD von 110,70 cm Reihenabständen erhöht als bei Abständen von 150,110 cm; in diesem Fall nahm der Ertrag je Pflanze mit einer Zunahme von PPD für zweifache Ernte stärker zu als bei Pflanzen mit einmaliger Aberntung. Dies lässt vermuten, dass hohe PPD in frühen Stadien des Wachstums bedeutend ist für die Förderung des Bestandesertrages in dieser Umwelt, da wahrscheinlich Trockeneinflüsse im Herbst abschwächt werden. Die Einflüsse von PPD auf die Spross-Zusammensetzung war gering und lässt vermuten, dass die Pflanzenreife kaum von der Bestandesdichte abhängig ist. Es wird angenommen, dass der Halt der Pflanzenbedeckung in den frühen Stadien des Wachstums Bedeutung für hohe Erträge in der Savannenregion hat; dies kann mit Reihenabständen nicht über 70 cm und dem Vermeiden einer Zwischenernte erreicht werden. [source] Variations in Chemical Composition of Clay Minerals and Magnetic Susceptibility of Hydrothermally Altered Rocks in the Hishikari Epithermal Gold Deposit, SW Kyushu, JapanRESOURCE GEOLOGY, Issue 1 2008Hiroyasu Murakami Abstract Hydrothermal alteration, involving chiefly chlorite and illite, is extensively distributed within host rocks of the Pleistocene Hishikari Lower Andesites (HLA) and the Cretaceous Shimanto Supergroup (SSG) in the underground mining area of the Hishikari epithermal gold deposit, Kagoshima, Japan. Approximately 60% of the mineable auriferous quartz-adularia veins in the Honko vein system occur in sedimentary rocks of the SSG, whereas all the veins of the Yamada vein system occur in volcanic rocks of the HLA. Variations in the abundance and chemical composition of hydrothermal minerals and magnetic susceptibility of the hydrothermally altered rocks of the HLA and SSG were analyzed. In volcanic rocks of the HLA, hydrothermal minerals such as quartz, chlorite, adularia, illite, and pyrite replaced primary minerals. The amount of hydrothermal minerals in the volcanic rocks including chlorite, adularia, illite, and pyrite as well as the altered and/or replaced pyroxenes and plagioclase phenocrysts increases toward the veins in the Honko vein system. The vein-centered variation in mineral assemblage is pronounced within up to 25 m from the veins in the peripheral area of the Honko vein system, whereas it is not as apparent in the Yamada vein system. The hydrothermal minerals in sandstone of the SSG occur mainly as seams less than a few millimeters thick and are sporadically observed in halos along the veins and/or the seams. The alteration halos in sandstone of the SSG are restricted to within 1 m of the veins. In the peripheral area of the Honko vein system, chlorite in volcanic rocks is characterized by increasing in Al in its tetrahedral layer and the Fe/Fe + Mg ratio toward the veins, while illite in volcanic rocks has relatively low K and a restricted range of Fe/Fe + Mg ratios. Temperature estimates derived from chlorite geothermometry rise toward the veins within the volcanic rocks. The magnetic susceptibility of tuff breccia of the HLA varies from 21 to less than 0.01 × 10,3 SI within a span of 40 m from the veins and has significant variation relative to that of andesite (27,0.06 × 10,3 SI). The variation peripheral to the Honko vein system correlates with an increase in the abundance of hematite pseudomorphs after magnetite, the percentage of adularia and chlorite with high Fe/Fe + Mg ratios, and the degree of plagioclase alteration with decreasing distance to the veins. In contrast, sedimentary rocks of the SSG maintain a consistent magnetic susceptibility across the alteration zone, within a narrow range from 0.3 to 0.2 × 10,3 SI. Magnetic susceptibility of volcanic rocks of the HLA, especially tuff breccia, could serve as an effective exploration tool for identifying altered volcanic rocks. [source] Chemical Composition of Rock-Forming Minerals in Copper,Gold-Bearing Tonalite Porphyries at the Batu Hijau Deposit, Sumbawa Island, Indonesia: Implications for Crystallization Conditions and Fluorine,Chlorine FugacityRESOURCE GEOLOGY, Issue 2 2007Arifudin Idrus Abstract Copper,gold mineralization at the world-class Batu Hijau porphyry deposit, Sumbawa Island, Indonesia, is closely related to the emplacement of multiple stages of tonalite porphyries. Petrographic examination indicates that at least two texturally distinct types of tonalite porphyries are currently recognized in the deposit, which are designated as "intermediate tonalite" and "young tonalite". They are mineralogically identical, consisting of phenocrysts of plagioclase, hornblende, quartz, biotite and magnetite ± ilmenite, which are set in a medium-coarse grained groundmass of plagioclase and quartz. The chemical composition of the rock-forming minerals, including plagioclase, hornblende, biotite, magnetite and ilmenite in the tonalite porphyries was systematically analyzed by electron microprobe. The chemical data of these minerals were used to constrain the crystallization conditions and fluorine,chlorine fugacity of the corresponding tonalitic magma during its emplacement and crystallization. The crystallization conditions, including temperature (T), pressure (P) and oxygen fugacity (fO2), were calculated by applying the hornblende,plagioclase and magnetite,ilmenite thermometers and the Al-in-hornblende barometer. The thermobarometric data indicate that the tonalite porphyries were emplaced at 764 ± 22°C and 1.5 ± 0.3 × 105 kPa. If the pressure is assumed to be lithostatic, it is interpreted that the rim of hornblende and plagioclase phenocrysts crystallized at depths of approximately 5.5 km. As estimated from magnetite,ilmenite thermometry, the subsolidus conditions of the tonalite intrusion occurred at temperatures of 540,590°C and log fO2 ranging from ,20 to ,15 (between Ni-NiO and hematite,magnetite buffers). This occurred at relatively high fO2 (oxidizing) condition. The fluorine,chlorine fugacity in the magma during crystallization was determined on the basis of the chemical composition of magmatic biotite. The calculation indicates that the fluorine,chlorine fugacity, represented by log (fH2O)/(fHF) and (fH2O)/(fHCl) in the corresponding tonalitic magma range from 4.31 to 4.63 and 3.62 to 3.79, respectively. The chlorine fugacity (HCl) to water (H2O) is relatively higher than the fluorine fugacity (HF to water), reflecting a high activity of chlorine in the tonalitic magma during crystallization. The relatively higher activity of chlorine (rather than fluorine) may indicate the significant role of chloride complexes (CuCl2, and AuCl2,) in transporting and precipitating copper and gold at the Batu Hijau deposit. [source] Chemical Composition of Ancient Celadon Material (1127,1279 A.D.) from Zhejiang, China and Its ImplicationACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 5 2006PENG Zicheng Abstract: The microprobe EDXRF equipment was used for analysis of the major and trace elements in glaze layer-transitive layer-body layer of the celadon from the Altar Yao (Kiln) and Laohudong Yao in the Southern Song Dynasty (1127,1279 A.D.), Zhejiang, China. The K values of the discriminant factor for the celadon wares are larger than 8, which means the celadon of the Altar Yao and Laohudong Yao are different from that of the Longquan Yao. The former two belong to the Guan Yao system (the Chinese imperial kilns), but the latter to the Min Yao system (the Chinese popular kilns). The principle component analysis shows their relationship between the Altar and Laohudong wares with provenance postulation. The thickness of the transitive layer in the Altar and Laohudong wares is obviously different, which reveals the microstructure characteristics of the celadon even though both kinds of wares belong to the imperial kiln system. [source] Surface Chemical Composition of DiatomsCHEMBIOCHEM, Issue 12 2009Benoit Tesson Dr. No abstract is available for this article. [source] Effect of Pedoclimatic Conditions on the Chemical Composition of the Sigoise Olive CultivarCHEMISTRY & BIODIVERSITY, Issue 4 2010Samia Dabbou Abstract The present work focused on the quality and the chemical composition of monovarietal virgin olive oil from the Sigoise variety grown in two different locations in Tunisia, viz., a sub-humid zone (Béjaoua, Tunis) and an arid zone (Boughrara, Sfax). In addition to the quality characteristics (acidity, peroxide value, and the spectrophotometric indices K232 and K270) and the chemical composition (content of fatty acids, antioxidants, and volatile compounds) of the oil, the fruit characteristics of the olives were studied. Except for the content of the majority of the fatty acids, there were significant differences observed in the oil composition of olives that were cultivated in different locations. The content of total phenols and lipoxygenase (LOX) oxidation products was higher for olives grown at the higher altitude, whereas that of , -tocopherol, carotenes, and chlorophylls was higher for olives from the Boughrara region (lower altitude). Moreover, olives produced at the higher altitude showed a higher ripeness index and oil content than those cultivated at the lower altitude. [source] Chemical Composition of Hydrodistilled Essential Oil of Artemisia incana (L.) Druce and Antimicrobial Activity against Foodborne MicroorganismsCHEMISTRY & BIODIVERSITY, Issue 12 2009Bülent Çetin Abstract The oil obtained by hydrodistillation from the aerial parts of Artemisia incana (L.) Druce from Turkey was analyzed by GC and GC/MS. Sixty-three compounds were characterized, representing 97.2% of the total components detected, and camphor (19.0%), borneol (18.9%), 1,8-cineole (14.5%), bornyl acetate (7.8%), camphene (4.9%), and , -thujone (4.8%) were identified as predominant components. The essential oil was also tested for its antimicrobial activity against 44 different foodborne microorganisms, including 26 bacteria, 15 fungi, and 3 yeast species. The essential oil of A. incana exhibited considerable inhibitory effects against all bacteria, fungi, and yeast species tested. However, the oil showed lower inhibitory activity against the tested bacteria than the reference antibiotics. [source] Ag-rich Tetrahedrite in the El Zancudo Deposit, Colombia: Occurrence, Chemical Compositions and Genetic TemperaturesRESOURCE GEOLOGY, Issue 3 2010Alba Nury Gallego Hernández Abstract Chemical compositions of tetrahedrite,Ag-rich tetrahedrite,freibergite solid solutions (Ag-rich tetrahedritess) and homogenization temperatures of fluid inclusions in quartz and carbonates of seventeen samples from nine veins in the El Zancudo deposit, Antioquia, Colombia, were investigated to reveal the origin of silver in Ag-rich tetrahedritess, to derive their crystallization temperatures and to examine the relationship between chemical compositions of Ag-rich tetrahedritess and their crystallization temperatures. The ores consist of arsenopyrite, pyrite, sphalerite, Ag-rich tetrahedritess, galena, boulangerite, andorite, owyheeite, diaphorite, jamesonite, miargyrite, bournonite, chalcopyrite, and electrum. Ag-rich tetrahedritess forms about 10 volume % of the total ores and is one of the most common and widely distributed sulfosalts in this deposit. Ag-rich tetrahedritess is rich in Ag (1.13 to 31.02 wt%) and Sb (22.93 to 29.82 wt%), and poor in As (0.06 to 2.43 wt%), consistent with the reported incompatibilities of Ag and As in Ag-rich tetrahedritess. The Zn/(Zn + Fe)-, Ag/(Ag + Cu)- and Sb/(Sb + As + Bi)-atomic ratios exhibit some variations among the veins. Ag-rich tetrahedritess with higher Ag/(Ag + Cu) ratios coexist with diaphorite, whereas those with lower ratios are not associated with this sulfosalt. Ag-rich tetrahedritess in the assemblages of Ag-rich tetrahedritess+ sphalerite and of Ag-rich tetrahedritess+ bournonite + galena shows no Zn , Fe and Cu , Ag variations between core and rim, respectively, negating the possibility of solid state reaction during cooling. Ag-rich tetrahedritess is thus regarded as primary phase. Homogenization temperatures of primary fluid inclusions in quartz and carbonates co-existing with Ag-rich tetrahedritess define the mineralization temperatures of 134 to 263°C. Independent crystallization temperatures of Ag-rich tetrahedrite estimated based on Zn/(Zn + Fe) and Ag/(Ag + Cu) ratios of the Ag-rich tetrahedritess associated with silver minerals such as miargyrite, andorite and diaphorite using Sack's thermochemical database lie in a range between 170 and ,250°C. Both results are thus in good agreement. [source] Chemical composition of Pinus sibirica nut oilsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2009Ryszard Zadernowski Abstract The chemical composition of oil obtained from Pinus sibirica was investigated. The nonpolar lipids were the predominant lipid fraction while the triacylglycerols were the major component of this fraction. ,- and ,-tocopherols were the dominant tocopherols in pine oils. Eleven fatty acids (FA) were identified in pine nut oil. The unsaturated FA comprised over 90% of the total FA. Of these, polyunsaturated FA accounted for 66% of the total FA. 18:2 and 18:3 acids were the dominant unsaturated FA, while palmitic and stearic acids were the major saturated FA. Three unusual FA, namely 10,13-octadecadienoic, gorlic and 11,13-eicosadienoic acid, were tentatively identified in pine nut oil. [source] Chemical composition of essential oils from aerial parts of Cinnamomum malabatrum (Burman f.) Bercht & Presl.FLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2009N. K. Leela Abstract The constituents of the essential oils of leaf, petiole, shoot and terminal shoot of Cinnamomum malabatrum were determined by GC and GC,MS. Thirty-nine compounds, constituting 95% of the oil, were identified in the leaves. Major constituents of the leaf oil were (E)-caryophyllene (28.6%), (E)-cinnamyl acetate (15.1%), bicyclogermacrene (14.4%) and benzyl benzoate (8.5%). Twenty-eight compounds, representing 98% and 97% of the oil, were identified in the petioles and shoots, respectively, whereas in the oil of the terminal shoots 34 compounds, accounting for 97%, were identified. The essential oils of the petioles, shoots and terminal shoots were dominated by linalool (77.8,79.4%). This is the first report of the essential oil constituents of C. malabatrum. Copyright © 2008 John Wiley & Sons, Ltd. [source] Chemical composition of the essential oils from Eriocephalus africanus L. var. africanus populations growing in SpainFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2007Hugo Merle Abstract Essential oils from the aerial parts of three Eriocephalus africanus L. var. africanus populations were analysed by means of GC,FID and GC,MS. Sixty-one constituents were identified, representing more than 96% of the total oil composition. Artemisia ketone (56.46,56.58%), intermedeol (9.19,11.63%) and , -eudesmol (4.26,5.64%) were the main compounds. Application of the Pearson correlation coefficient showed high similarity between the nine samples analysed. Copyright © 2007 John Wiley & Sons, Ltd. [source] Chemical composition of the essential oil from Vernonia scorpioides (Asteraceae)FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2007Maria Rose Jane R. Albuquerque Abstract The essential oil from aerial parts of Vernonia scorpiodes was obtained by hydrodistillation in a Clevenger-type apparatus. Qualitative and quantitative analysis were performed by GC,FID and GC,MS, respectively. A total of 18 compounds, representing 95.3% of the total volatile content, were identified. The major components found were , -caryophyllene (30.6%), germacrene D (27.3%), and bicyclogermacrene (8.5%). Copyright © 2007 John Wiley & Sons, Ltd. [source] Chemical composition and antibacterial activity of the essential oil of Michelia foveolata Merryll ex Dandy from VietnamFLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2007Dominique Lesueur Abstract The chemical composition of the volatile oil extracted from aerial parts (twigs, leaves and flowers) of Michelia foveolata growing wild in Vietnam was investigated by combination of column chromatography, GC (retention indices), GC,MS and 13C-NMR spectroscopy. Fifty-eight components were identified, with sabinene (32.4%) and terpinen-4-ol (13.7%) as the main constituents. The essential oil was tested against 11 bacteria using the agar disc diffusion method, and exhibited a significant antibacterial activity against Salmonella enterica, Staphylococcus epidermidis, Staphylococcus aureus and Bacillus cereus (MICs = 2,4 µl/ml). Copyright © 2007 John Wiley & Sons, Ltd. [source] Chemical composition of essential oil from the seeds of Nigella arvensis L. and assessment of its actimicrobial activityFLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2006J. Havlik Abstract The essential oil from Nigella arvensis L. was obtained by hydrodistillation, yielding 0.42% of oil on dry weight basis. The GC and GC-MS analyses showed the presence of 69 components, predominantly monoterpenes. The major constituents were carvacrol methyl ether (26.4%), , -pinene (21.4%), n -undecane (13.2%), and , -pinene (5.7%). The oil did not exhibit antimicrobial activity when tested by microdilution method. Copyright © 2006 John Wiley & Sons, Ltd. [source] Chemical composition of the essential oils of Rubia tinctorum L. aerial parts from IranFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2006Mehrdokht Najafpour Navaei Abstract Hydro-distilled volatile oil from the aerial parts of Rubia tinctorum L. was obtained at yield of 0.1% w/w based on dry weight. The oil was analyzed by a combination of GC and GC-MS. Thirty-four components were identified, constituting 96.4% of the oil. The major constituents in the oil were pentadecanal (20.2%), tridecanal (16.7%) and globulol (7.8%). Copyright © 2006 John Wiley & Sons, Ltd. [source] Chemical composition of essential oils of two submerged macrophytes, Ceratophyllum demersum L. and Vallisneria spiralis L.FLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2006Xian Qiming Abstract The essential oils from leaves of Ceratophyllum demersum L. and Vallisneria spiralis L. from China were isolated by steam distillation in yields of 0.15% and 0.10%, respectively, and their chemical composition was examined by GC and GC,MS. More than 50 constituents were identified, representing 87% of the total oils. The main components were basically the same in the two plants' essential oils. 2-Methylpropanoic acid 3-hydroxy-2,4,4-trimethylpentyl ester (>15%), 2-methylpropanoic acid 2,2-dimethyl-1-(2-hydroxy-1-methylethyl)propyl ester (>3%), , -ionone-5,6-epoxide (>7%), toluene (>6%), hexanal (>5%) and 1,2-benzenedicarboxylic acid di(2-methylpropyl) ester (>5%) were the major components. Copyright © 2006 John Wiley & Sons, Ltd. [source] Chemical composition of the essential oils of Astrodaucus persicus (Boiss.) Drude root, stem/leaves and flowers/fruitsFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2006Y. T. Bazargani Abstract The essential oils of Astrodaucus persicus (Boiss.) Drude were obtained by hydrodistillation of root and aerial parts and examined by GC and GC,MS. The composition of oil samples was compared; 22, 20 and 14 compounds were identified in the essential oils of the root, stem/leaves and flowers/fruits, representing 94.4%, 99.7% and 99.9%, respectively, of the total oils. The major components were bornyl acetate (26.5%), , -sesquiphellandrene (25.9%) and exo -fenchyl acetate (25.1%) for the root oil, , -pinene (56.4%) and exo -fenchyl acetate (37.7%) for the stem/leaves oil and , -pinene (46.1%), , -pinene (26.1%) and , -thujene (14.4%) for the flowers/fruits oil. The highest amount of sesquiterpenes was found in the root oil (30.7%). Copyright © 2005 John Wiley & Sons, Ltd. [source] Chemical composition and biological activities of the essential oils of Salvia canariensisFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2006M. C. García Vallejo Abstract Comparative studies of the chemical composition of steam-distilled essential oils from cultivated Salvia canariensis, collected at different seasons of the year, were studied. The essential oils were analysed by gas chomatography,mass spectrometry: the major components were bornyl acetate (17.8,28.6%), , -caryophyllene (12.7,30.2%), , -pinene (4.6,9.5%) and viridiflorol (13.9,17.3%) in all samples. The essential oils were evaluated for antimicrobial and cytostatic activities and enzymatic inhibitions of xanthine oxidase, , -glucosidase and , -glucuronidase. Concerning the antimicrobial and cytotoxic tests, the oils showed interesting activities towards different Gram-positive bacteria (MIC 45,35 µg[sol ]ml), but had no effect against eukaryotic cells. Copyright © 2005 John Wiley & Sons, Ltd. [source] Chemical composition and antimicrobial activity of essential oils from Tunisian Pituranthos tortuosus (Coss.) MaireFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2006A. Abdelwahed Abstract The aerial parts of Pituranthos tortuosus, collected during November and April, were analysed by GC and GC,MS. In total, 56 compounds were identified by their retention indices. Antimicrobial assays showed that the November essential oil is more effective than that of April against the Gram-positive bacteria Enterococcus faecalis and Staphylococcus aureus. The April essential oil displayed the highest activity against Staphylococcus aureus. Copyright © 2005 John Wiley & Sons, Ltd. [source] Chemical composition of essential oil from Acroptilon repens (L.) DCFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2005M. Mirza Abstract A sample of essential oil obtained from aerial parts of Acroptilon repens (L.) DC. (Asteraceae) was examined by GC and GC/MS. Thirteen compounds were identified representing about 99.7% of the oil, with caryophyllene oxide (54.7%), , -copaene (14.8%) and , -caryophyllene (12.1%) as major constituents. Copyright © 2005 John Wiley & Sons, Ltd. [source] Chemical composition of essential oils of two Hyptis suaveolens (L.) Poit leaves from NigeriaFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2005Adeolu O. Eshilokun Abstract The essential oils of the leaves of Hyptis suaveolens (L.) Poit collected from two different sources were isolated by hydrodistillation. The oils were analysed by GC and GC_MS; 36 constituents were identified in the oil of sample collected from the campus of Lagos State University (LASU), while 33 constituents were identified in the oil of sample from Obafemi Awolowo University (OAU). , -Pinene (13.6%), sabinene (13.2%), p -cymene (11.7%), terpinen-4-ol (9.8%) and terpinolene (6.3%) were the major monoterpenes in the LASU oil sample, while sabinene (30.0%), terpinen-4-ol (11.4%), terpinolene (5.6%), 1,8-cineole (5.2%), , -pinene (4.4%) and , -terpinene (4.2%) were the main monoterpenes in the OAU oil sample. , -caryophyllene (5.1_5.9%) and trans - , -bergamotene (1.6_5.2%) represented the major sesquiterpenes in both oils. Copyright © 2005 John Wiley & Sons, Ltd. [source] Chemical composition of the essential oils of Marrubium parvi,orum Fisch.FLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2005& C. A. Mey., Marrubium vulgare L. from Iran Abstract The composition of essential oil samples obtained by hydrodistillation of the aerial parts of Marrubium parvi,orum Fisch. & C. A. Mey. and Marrubium vulgare L. (family Lamiaceae), were investigated by GC and GC,MS. Fifty-one components in the oil of M. parvi,orum, representing 96.8% of the total oil, and 34 components in the oil of M. vulgare, representing 95.1% of the total oil, were identi,ed. Both essential oils were characterized by a high amount of sesqiterpenes (77.8% and 82.5%, respectively) with bicyclogermacrene (26.3%), germacrene D (21.5%) and , -caryophyllene (15.6%) as the major constituents of M. parvi,orum, and , -bisabolene (25.4%), , -caryophyllene (11.6%), germacrene D (9.7%) and E - , -farnesene (8.3%) as the major component of M. vulgare. Copyright © 2004 John Wiley & Sons, Ltd. [source] Chemical composition and olfactory characterization of essential oils of fruits and seeds of African pear (Dacryodes edulis (G. Don) H. J. Lam) from CameroonFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005Leopold Jirovetz Abstract The composition of the essential oil of Dacryodes edulis (G. Don) H. J. Lam (Burseraceae) fruits and seeds from Cameroon were investigated by gas chromatographic,spectroscopic (GC,FID and GC,MS) and olfactory methods to identify those volatiles responsible for the characteristic aroma of this commonly known African pear. Monoterpenes, such as , -pinene (fruits/seeds: 22.3/21.5%), , -pinene (13.7/19.7%), limonene (7.2/27.5%) and , -phellandrene (10.8/12.1%) were found to be main compounds of these essential oils. A correlation of the identi,ed constituents of the two essential oils of African pear from Cameroon with their single odour impressions is also given. Copyright © 2004 John Wiley & Sons, Ltd. [source] Chemical composition of the essential oil of nine Eucalyptus species growing in MoroccoFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2004S. Zrira Abstract The essential oils obtained by steam distillation from the leaves of nine Eucalyptus species (E. cinerea F. Muell., E. baueriana F. Muell., E. smithii R. T. Baker, E. bridgesiana R. T. Baker, E. microtheca F. Muell., E. foecunda Schau., E. pulverulenta Sims, E. propinqua Deane and Maiden, E. erythrocorys F. Muell.) of Moroccan origin have been analysed using GC and GC,MS. A total of 83 constituents were identi,ed. All the species investigated were found to possess an oil rich in 1,8-cineole (>68%). In ,ve species (E. cinerea F. Muell., E. baueriana F. Muell., E. smithii R. T. Baker, E. bridgesiana R. T. Baker and E. microtheca F. Muell.), the 1,8-cineole content exceeded 80%. Copyright © 2004 John Wiley & Sons, Ltd. [source] Chemical composition of the essential oils of Ageratum conyzoides L. occurring in south ChinaFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2004Abu James Sundufu Abstract The essential oil isolated from the leaves and ,owers of Ageratum conyzoides L. were analysed by GC and GC,MS. The oil contained ageratochromene (precocene II, 25.89%); the sesquiterpene , -caryophyllene (23.79%); demethoxyageratochromene (precocene I, 14.76%) and some monoterpene hydrocarbons, with percentages of 2,5.5%. Comparative analysis with data from Cameroon, Ghana and Vietnam is also reported. Copyright © 2003 John Wiley & Sons, Ltd. [source] Chemical composition of the essential oil of Pistacia lentiscus L. from Morocco,a seasonal variationFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2003S. Zrira Abstract Air-dried aerial parts of Pistacia lentiscus L. collected from different regions of Morocco (Mehdia, Oulmes and Chaouen) were water-distilled to produce oil in 0.2% yields. The chemical composition of P. lentiscus oils changes from a region to another. The variations in chemical composition are important between plant populations. A total of 45 constituents were identi,ed. The major oil components of P. lentiscus from Oulmes were , -pinene (16.5,38.5%), , -myrcene (10.2,11.5%) and limonene (6.8,9.8%), while terpinen-4-ol (32.7,43.8%), , -pinene (7.1,13.5%) and bornyl acetate (6.8,10.3%) were the main constituents of Chaouen oil. For P. lentiscus from Mehdia, terpinen-4-ol (14.5,19.3%), caryophyllene oxide (6.5,10.3%) and limonene (6.7,8.1%) were the major components. The effect of harvesting time on the oil production and chemical composition was also examined at different vegetative stages (December,June). For the three locations, the best oil content was obtained during the ,owering period March,June. Copyright © 2003 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||