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Abundant Compounds (abundant + compound)
Selected AbstractsChanges in the Disposition of Oxcarbazepine and Its Metabolites during Pregnancy and the PuerperiumEPILEPSIA, Issue 3 2006Iolanda Mazzucchelli Summary:,Purpose: To determine potential changes in the plasma concentrations of oxcarbazepine (OXC) and its metabolites during pregnancy and puerperium. Methods: Five women receiving OXC monotherapy were followed prospectively during pregnancy and the puerperium. Four women were enrolled in the first trimester, and one woman, 2 weeks before delivery. Steady-state concentrations of OXC, its active R -(-)- and S -(+)-monohydroxy derivatives (MHD), and the additional metabolite carbamazepine-10,11- trans -dihydrodiol (DHD) were measured at regular intervals by an enantioselective HPLC assay. Results. In all samples, S -(+)-MHD was the most abundant compound in plasma and accounted almost entirely for the amount of active moiety (defined as the molar sum of OXC, R -(-)-MHD, and S -(+)-MHD) found in the circulation. The dose-normalized concentrations of active moiety decreased markedly during gestation and, in four of the five patients, increased strikingly after delivery. Plasma concentrations of S -(+)-MHD mirrored closely the levels of the active moiety. Plasma concentrations of the parent drug and other metabolites also tended to decrease during pregnancy and to increase after delivery. Conclusions: During treatment with OXC, S -(+)-MHD is by far the most abundant active compound in plasma. The concentration of this metabolite as well as the active moiety may decrease markedly during pregnancy and may increase severalfold after delivery. Because of these striking pharmacokinetic changes, the clinical response should be monitored closely in OXC-treated women throughout pregnancy and the puerperium. [source] A comparative study of the essential oils of the genus Plumeria Linn. from MalaysiaFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2006Norsita Tohar Abstract The chemical composition of the flower oils of three Malaysian Plumeria Linn. species, P. acuminata Ait. (white flower), P. rubra Linn. (reddish-orange flower) and P. rubra Linn. (red flower), were determined by gas chromatography on two columns of different polarity, GC,MS and Kováts retention indices. The oil of P. acuminata Ait. (white flower) was made up predominantly of benzyl salicylate (39.0%), benzyl benzoate (17.2%), trans -nerolidol (10.6%), neryl phenylacetate (10.5%) and linalool (8.9%). Phenylethyl benzoate at 12.3% was the most abundant compound in the oil of P. rubra Linn. (reddish-orange flower), followed by dodecanoic acid at 11.8% concentration. Hexadecanoic acid constituted 9.3% and 27.2% of the oils of P. rubra Linn. (reddish-orange flower) and P. rubra Linn. (red flower), respectively. Copyright © 2006 John Wiley & Sons, Ltd. [source] Analysis and characterization of aroma-active compounds of Schizandra chinensis (omija) leavesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2005Cheng Hao Zheng Abstract Volatile components from leaves of Schizandra chinensis (omija), a native plant of Korea, were extracted by simultaneous distillation,extraction (SDE) and analyzed by gas chromatography,mass spectrometry (GC-MS) using two types of capillary column with different polarities (DB-5MS and DB-Wax). The GC-MS analysis of volatile compounds obtained by SDE revealed that germacrene D is the most abundant compound (22.6%) in omija leaves, followed by ,-elemene (17.4%), (E)-2-hexenal (8.7%), and (E)-,-ocimene (7.2%). Aroma-active compounds were determined by gas chromatography,olfactometry (GC-O) using the aroma-extract-dilution analysis method. (E,Z)-2,6-Nonadienal (cucumber) was the most intense aroma-active compound due to its higher flavor-dilution factor (243,729) than any other compound. (Z)-3-Hexenal (green/apple), (E)-2-hexenal (green/fruity), and (E)-,-ocimene (wither green/grass) were also identified as important aroma-active compounds by GC-O. In addition, the volatile compounds were extracted by solid-phase microextraction (SPME), and the quantitative analysis of the SPME samples gave slightly different results, depending on the type of SPME fiber, compared with those from SDE, However, the aroma-active compounds identified in SPME were similar to those in SDE. Copyright © 2004 Society of Chemical Industry [source] Betulin induces mitochondrial cytochrome c release associated apoptosis in human cancer cellsMOLECULAR CARCINOGENESIS, Issue 7 2010Yang Li Abstract We examined whether betulin, a naturally abundant compound, has anticancer functions in human cancer cells. The results showed that betulin significantly inhibited cell viability in cervix carcinoma HeLa cells, hepatoma HepG2 cells, lung adenocarcinoma A549 cells, and breast cancer MCF-7 cells with IC50 values ranging from 10 to 15,µg/mL. While betulin exhibited only moderate anticancer activity in other human cancer cells such as hepatoma SK-HEP-1 cells, prostate carcinoma PC-3, and lung carcinoma NCI-H460, with IC50 values ranging from 20 to 60,µg/mL, it showed minor growth inhibition in human erythroleukemia K562 cells (IC50,>,100,µg/mL). We further investigated the mechanism of anticancer activity by betulin, using HeLa cells as an experimental model. Betulin (10,µg/mL) induces apoptotic cell death, as evidenced by morphological characteristics such as membrane phosphatidylserine translocation, nuclear condensation/fragmentation, and apoptotic body formation. A kinetics analysis showed that the depolarization of mitochondrial membrane potential and the release of mitochondrial cytochrome c occurred as early as 30,min after treatment with betulin. Betulin, unlike its chemical derivative betulinic acid, did not directly trigger mitochondrial cytochrome c release in isolated mitochondria. Importantly, Bax and Bak were rapidly translocated to the mitochondria 30,min after betulin treatment. The sequential activation of caspase-9 and caspase-3/-7 and the cleavage of poly(ADP-ribose) polymerase (PARP) were observed behind those mitochondrial events. Furthermore, specific downregulation of either caspase-9, Bax, or Bak by siRNA effectively reduced PARP cleavage and caspase-3 activation. Taken together, the lines of evidence demonstrate that betulin triggers apoptosis of human cancer cells through the intrinsic apoptotic pathway. © 2010 Wiley-Liss, Inc. [source] Effect of fermentation on free and bound volatile compounds of orange juiceFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2009Gang Fan Abstract Aroma is one of the most important attributes of orange wine quality. The volatile compounds in orange wine mainly derive from oranges, yeast fermentation and compounds released from odourless glycosidic precursors present in the orange. In this study, free volatile compounds in orange juice and wine made from Citrus sinensis (L). Osbeck cv. Washington Sanguine were analysed by SPME-GC,MS. Bound fractions were isolated and extracted with methanol and Amberlite XAD-2 resin and then hydrolysed by almond , -glucosidase. Totals of 31 and 19 free volatiles were identified in orange juice and wines, respectively. Terpenes were the most abundant compounds in orange juice, while esters were quantitatively the dominant group in orange wine and most of them were compounds newly formed during fermentation, such as isoamyl acetate, ethyl hexanoate, ethyl benzoate, diethyl succinate, ethyl decanoate and ethyl laurate. In total, 11 and three released bound volatiles were found in orange juice and wine, respectively, and most of them were not found in free form. Only ethyl 3-hydroxyhexanoate and cis -carveol were found present in both the free and bound forms of orange juice. Copyright © 2009 John Wiley & Sons, Ltd. [source] Essential oil composition of Croton cuneatus and Croton malambo growing in VenezuelaFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2005Alírica I. Suárez Abstract The bark of Croton malambo and the aerial parts of Croton cuneatus were subjected to hydrodistillation to obtain the essential oils of each specie. The composition of these samples were analysed by GC-MS and by NMR. The analysis of the C. malambo oil showed 36 constituents including traces, in which methyl eugenol (65.4%), methyl isoeugenol (6.3%), elemicine (4.7%), isoelemicine (3.4%), veratral (3.0%) and , -cadinol (4.1%) were the major components. C. cuneatus oil was found to be rich in phenylpropanoids and sesquiterpene alcohols, showing 43 compounds, where , -11-eudesmene (51.3%), methyleugenol (25.9%), 4- , -seleniol (10.2%), cedryl propyl ether (2.9%), , -cadinol (4.4%), cubenol (1.3%) methyl isoeugenol (1.2%), veratral (1.3%) and agarospirol (1.0%) were the most abundant compounds. Copyright © 2005 John Wiley & Sons, Ltd. [source] Chemical constituents of the essential oils of Goniothalamus malayanus Hook. f. and Thoms.FLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2002Ibrahim bin Jantan Abstract The chemical composition of the leaf, bark and root oils of Goniothalamus malayanus Hook. f. and Thoms. was examined by capillary GC and GC,MS. The leaf oil was made up mainly of sesquiterpenoids, of which ,-selinene (33.6%) was the dominant component. The other major compounds present were viridiflorol (13.1%), epi -globulol (7.7%), (E)-nerolidol (4.4%) and globulol (3.8%). The bark and root oils, which were qualitatively similar but with some variation in levels of the individual constituents, were also rich in sesquiterpenoids (97% and 95%, respectively), with eudesmols as the most abundant compounds. The bark oil contained a higher amount of ,-eudesmol (32.2%), ,-eudesmol (21.8%) and ,-eudesmol (6.6%) than the root oil. Copyright © 2002 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] Bacterial formation of phosphatic laminites off PeruGEOBIOLOGY, Issue 3 2009E. T. ARNING Authigenic phosphatic laminites enclosed in phosphorite crusts from the shelf off Peru (10°01, S and 10°24, S) consist of carbonate fluorapatite layers, which contain abundant sulfide minerals including pyrite (FeS2) and sphalerite (ZnS). Low ,34Spyrite values (average ,28.8,) agree with bacterial sulfate reduction and subsequent pyrite formation. Stable sulfur isotopic compositions of sulfate bound in carbonate fluorapatite are lower than that of sulfate from ambient sea water, suggesting bacterial reoxidation of sulfide by sulfide-oxidizing bacteria. The release of phosphorus and subsequent formation of the autochthonous phosphatic laminites are apparently caused by the activity of sulfate-reducing bacteria and associated sulfide-oxidizing bacteria. Following an extraction,phosphorite dissolution,extraction procedure, molecular fossils of sulfate-reducing bacteria (mono- O -alkyl glycerol ethers, di- O -alkyl glycerol ethers, as well as the short-chain branched fatty acids i/ai -C15:0, i/ai -C17:0 and 10MeC16:0) are found to be among the most abundant compounds. The fact that these molecular fossils of sulfate-reducing bacteria are distinctly more abundant after dissolution of the phosphatic laminite reveals that the lipids are tightly bound to the mineral lattice of carbonate fluorapatite. Moreover, compared with the autochthonous laminite, molecular fossils of sulfate-reducing bacteria are: (1) significantly less abundant and (2) not as tightly bound to the mineral lattice in the other, allochthonous facies of the Peruvian crusts consisting of phosphatic coated grains. These observations confirm the importance of sulfate-reducing bacteria in the formation of the phosphatic laminite. Model calculations highlight that organic matter degradation by sulfate-reducing bacteria has the potential to liberate sufficient phosphorus for phosphogenesis. [source] EFFECTS OF PRESTORAGE DRY AND HUMID HOT AIR TREATMENTS ON THE QUALITY, TRIGLYCERIDES AND TOCOPHEROL CONTENTS IN ,HASS' AVOCADO FRUITJOURNAL OF FOOD QUALITY, Issue 2 2004J. DE JESUS ORNELAS P. ABSTRACT ,Hass' avocado fruit were heated with dry (50% RH) or moist (95% RH) forced air at 38Cfor 6 h and then stored at 5C and 85% RHfor up to 8 weeks. Fruit were evaluated weekly for quality and for the content of three triglycerides and three tocopherols. Heated fruit had higher weight loss. The nonheated fruit and those heated with dry air displayed the best external quality. Fruit heated with dry air exhibited the best internal quality and the lowest chilling injury incidence. The respiration rate was more intense in fruit heated with moist air. Fruit firmness immediately after harvest was 51N, but decreased to less than 20 N at the end of the storage period in the three treatments. The analysis of triglycerides and tocopherols showed that the 1,2-Dilinoleil-3-Oleil-Glycerol and ,-tocopherol were the most abundant compounds. Therefore, postharvest treatment with dry forced hot air before storage or transport reduces the incidence of chilling injury, and decreases quality deterioration in ,Hass' avocado fruit. [source] Chemical ecology of obligate pollination mutualisms: testing the ,private channel' hypothesis in the Breynia,Epicephala associationNEW PHYTOLOGIST, Issue 4 2010Glenn P. Svensson Summary ,Obligate mutualisms involving actively pollinating seed predators are among the most remarkable insect,plant relationships known, yet almost nothing is known about the chemistry of pollinator attraction in these systems. The extreme species specificity observed in these mutualisms may be maintained by specific chemical compounds through ,private channels'. Here, we tested this hypothesis using the monoecious Breynia vitis-idaea and its host-specific Epicephala pollinator as a model. ,Headspace samples were collected from both male and female flowers of the host. Gas chromatography with electroantennographic detection (GC-EAD), coupled gas chromatography,mass spectrometry, and olfactometer bioassays were used to identify the floral compounds acting as the pollinator attractant. ,Male and female flowers of B. vitis-idaea produced similar sets of general floral compounds, but in different ratios, and male flowers emitted significantly more scent than female flowers. A mixture of 2-phenylethyl alcohol and 2-phenylacetonitrile, the two most abundant compounds in male flowers, was as attractive to female moths as the male flower sample, although the individual compounds were slightly less attractive when tested separately. ,Data on the floral scent signals mediating obligate mutualisms involving active pollination are still very limited. We show that system-specific chemistry is not necessary for efficient host location by exclusive pollinators in these tightly coevolved mutualisms. [source] Chemical study of triterpenoid resinous materials in archaeological findings by means of direct exposure electron ionisation mass spectrometry and gas chromatography/mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2006Francesca Modugno A systematic study of standard triterpenes (, -amyrine, oleanolic acid, betulin, lupeol, betulinic acid and lupenone) and of raw resinous materials (frankincense resin, mastic resin and birch bark pitch) was performed using direct exposure electron ionisation mass spectrometry (DE-MS) and gas chromatography/mass spectrometry (GC/MS). DE-MS provides a mass spectral fingerprint of organic materials in a few minutes which highlights the compounds that are the main components in the sample. The application of principal component analysis (PCA) on DE-MS data in the mass ranges m/z 181,260 and m/z 331,500, corresponding to the fragmentation of triterpenoid molecules, enabled us to distinguish between different triterpenoid materials such as mastic resin, frankincense resin and birch bark pitch, and to graphically plot the resinous substances in three separate clusters, retaining 89% of the total variance. GC/MS analysis of the same materials has permitted us to elucidate in detail the molecular composition and to identify minor components and species that act as markers of the degradation undergone by the materials. The paper also reports the results for the organic residues contained in an Egyptian censer (5th,7th century AD) which was recovered in the excavation of the Necropolis of Antinoe (Egypt), and for the hafting material found on a Palaeolithic tool recovered at the site of Campitello (Arezzo, Tuscany), dating back to the Mid-Pleistocene period. Although DE-MS was found to be a fast analytical tool, it failed to give any information on the presence of less abundant compounds when applied to mixtures of different materials: only mastic resin was found in the residues from the Roman censer, whereas GC/MS analysis identified the presence of a vegetable oil from Brassicaceae seeds and Pinaceae resin. Birch bark pitch as a pure material was identified in the sample from the Palaeolithic flint flake using both procedures. Copyright © 2006 John Wiley & Sons, Ltd. [source] | |||||||||||||