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Major Compounds (major + compound)
Selected AbstractsInfluence of water and nitrogen deficit on fruit ripening and aroma potential of Vitis vinifera L cv Sauvignon blanc in field conditionsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2005Catherine Peyrot des Gachons Abstract S -Cysteine conjugate precursors of three volatile thiols were monitored in Vitis vinifera L cv Sauvignon blanc grapes during fruit ripening to assess the influence of vine water and nitrogen status on the grape aroma potential in field conditions. Four dry farmed plots were studied in the Pessac-Léognan and Graves appellations (Bordeaux area) in 1998, which was a very dry vintage, and in 1999, when regular summer rainfall occurred. Soil water-holding capacity ranged from very low to high. Soil total nitrogen content was related to soil organic matter content, which was highly variable on the four plots. Vine vigour was enhanced by both high water and nitrogen status. Major compounds in grapes depended mainly on vine water status. Water deficit-stressed vines produced small berries with low sugar and low total acidity. Grape aroma potential was highest in vines under mild water deficit and moderate nitrogen supply. Severe water deficit stress seemed to limit aroma potential, as did nitrogen deficiency. Consequences for site selection and irrigation management for Sauvignon blanc are discussed. Copyright © 2004 Society of Chemical Industry [source] Chemical composition of essential oils from needles, branches and cones of Pinus pinea, P. halepensis, P. pinaster and P. nigra from central ltalyFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2003F. Macchioni Abstract The composition of the essential oils from the needles, branches and female cones of four species of Pinaceae, Pinus pinea, P. halepensis, P. pinaster and P. nigra, has been analysed and comparative chemical evaluations were obtained. In P. pinea the major compound of the essential oils of all the three plant parts is limonene (58.9,62.5%), in P. halepensis, -pinene (18.1%,53.6%) and myrcene (13.7,42.1%), in P. pinaster, -pinene (24.7,40.4%) and , -pinene (21.7,29.2%), and in P. nigra, -pinene (28.4,61.7%). Copyright © 2003 John Wiley & Sons, Ltd. [source] Storage stability of a high dietary fibre powder from orange by-productsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2009Juana Fernández-López Summary The goal of this investigation was to evaluate the effects of storage time and conditions on the physicochemical and microbiological properties of a high dietary fibre powder (HDFP). HDFP for this study was manufactured from orange juice industry by-products. The storage period was 11 months and samples were stored under vacuum or air exposure and under dark or light exposure. The HDFP is a stable product (based on chemical, microbiological and physicochemical properties) with large amounts of dietary fibre (71.62 ± 0.24 g 100 g,1 dry sample) and polyphenols content (40.67 ± 0.45 mg g,1 dry sample). Hesperidin is the major compound identified in HDFP (higher than 50% of total phenolic compounds). The packaging material used protects the HDFP only up to 6 months. After this time, the increase in moisture content decreases the quality of the product. The best storage conditions are packaging under vacuum and darkness. Both conditions preserve the colour of the fibres probably by means of avoiding pigment degradation. [source] Anti-allergic properties of Mangifera indica L. extract (Vimang) and contribution of its glucosylxanthone mangiferinJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 3 2006Dagmar García Rivera Vimang is the brand name of formulations containing an extract of Mangifera indica L., ethnopharmacologically used in Cuba for the treatment of some immunopathological disorders, including bronchial asthma, atopic dermatitis and other allergic diseases. However, the effects of Vimang on allergic response have not been reported until now. In this study, the effects of Vimang and mangiferin, a C-glucosylxanthone isolated from the extract, on different parameters of allergic response are reported. Vimang and mangiferin showed a significant dose-dependent inhibition of IgE production in mice and anaphylaxis reaction in rats, histamine-induced vascular permeability and the histamine release induced by compound 48/80 from rat mast cells, and of lymphocyte proliferative response as evidence of the reduction of the amount of B and T lymphocytes able to contribute to allergic response. In these experiments, ketotifen, promethazine and disodium cromoglicate were used as reference drugs. Furthermore, we demonstrated that Vimang had an effect on an in-vivo model of inflammatory allergy mediated by mast cells. These results constitute the first report of the anti-allergic properties of Vimang on allergic models, as well as suggesting that this natural extract could be successfully used in the treatment of allergic disorders. Mangiferin, the major compound of Vimang, contributes to the anti-allergic effects of the extract. [source] Evaluation of detection methods for the reversed-phase HPLC determination of 3,,4,,5,-trimethoxyflavone in different phytopharmaceutical products and in human serumPHYTOCHEMICAL ANALYSIS, Issue 2 2001Christian W. Huck Abstract Quantitative determination of the major compound, 3,,4,,5,-trimethoxyflavone (1), in plant extracts, in tablets of Flos and of Radix Primulae veris and in human serum has been accomplished using reversed-phase HPLC with UV, fluorescence and mass spectrometric (MS) detection. Compared to UV detection, fluorescence detection showed greater selectivity, was 10-fold more sensitive and allowed the determination of 1 in human serum after sample pre-treatment by solid-phase extraction. MS detection of 1 using electrospray ionisation (ESI) interface could be improved by substituting trifluoroacetic acid with the more polar and less conductive additive acetic acid, giving rise to a 230-fold improvement in analyte detectability at the cost of an increase of only 45% in the peak width of the eluting peak at its half height. Further optimisation of the acetic acid concentration showed the highest signal intensity at 1.25% for HPLC-atmospheric pressure chemical ionisation (APCI)-MS and at 0.75% for HPLC-ESI-MS. The optimised MS method proved to be extremely selective, 50 times more sensitive than UV detection and 5 times more sensitive than fluorescence detection. Furthermore, fragment-ion spectra produced by collision induced dissociation-MS have been used as "fingerprints" for identifying compounds in the highly complex mixtures examine. Copyright © 2001 John Wiley & Sons, Ltd. [source] Inhibition of , -glucosidase and amylase by bartogenic acid isolated from Barringtonia racemosa Roxb. seedsPHYTOTHERAPY RESEARCH, Issue 8 2007P. Mangala Gowri Abstract Barringtonia racemosa presents a wide range of therapeutic applications. In the course of identifying bioactives from Indian medicinal plants it was observed that the hexane, ethanol and methanol extracts of B. racemosa seeds displayed potent yeast and intestinal , -glucosidase inhibitory activities. The methanol extract was found to be superior among them. However, none of the extracts exhibited pancreatic , -amylase inhibitory activity, rather the ethanol and methanol extracts accelerated the , -amylase enzyme activity. Interestingly, however, bartogenic acid isolated from the methanol extract inhibited , -amylase also. This is the first report identifying , -glucosidase inhibitory activity in B. racemosa seed extracts and assigning to bartogenic acid an , -glucosidase and amylase inhibitory property. The presence of bartogenic acid in B. racemosa seeds as a major compound is also reported for the first time in this communication. Copyright © 2007 John Wiley & Sons, Ltd. [source] Isolation of coumarins and ferulate from the roots of Angelica purpuraefolia and the antitumor activity of khellactonePHYTOTHERAPY RESEARCH, Issue 5 2007Hyeong-Kyu Lee Abstract A new coumarin, hydroxylomatin (1), was isolated from the CHCl3 -soluble fraction of the roots of Angelica purpuraefolia, along with one ferulate (2) and three other known coumarins (3,5) including khellactone (3). The structure of hydroxylomatin (1) was determined to be 3,,,5,-dihydroxy-3,,4,-dihydroseselin (1) by spectroscopic means including 2D-NMR. The modified Mosher's method was used to determine the chiral center at C-1 of compound 2. Khellactone (3) is a major compound of the roots of A. purpuraefolia. This study also examined the antitumor activity of khellactone (3) using a LLC mouse lung carcinoma in the BDF-1 mice and a NCI-H460 human lung carcinoma in a human tumor xenograft model in nude mice. This compound (3) inhibited LLC tumor growth with a T/C (mean value of treated group/mean value of control group) value of 12.9% at a dose of 5 mg/kg and 33.2% at a dose of 10 mg/kg, respectively, in a dose-dependent manner. In addition, it suppressed the growth of NCI-H460 tumor cells, accounting for 81.4% at a dose of 10 mg/kg in nude mice. Copyright © 2007 John Wiley & Sons, Ltd. [source] First report of non-coloured flavonoids in Echium plantagineum bee pollen: differentiation of isomers by liquid chromatography/ion trap mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 6 2010Federico Ferreres Apicultural products have been widely used in diet complements as well as in phytotherapy. Bee pollen from Echium plantagineum was analysed by high-performance liquid chromatography/photodiode-array detection coupled to ion trap mass spectrometry (HPLC-PAD-MSn) with an electrospray ionisation interface. The structures have been determined by the study of the ion mass fragmentation, which characterises the interglycosidic linkage in glycosylated flavonoids and differentiates positional isomers. Twelve non-coloured flavonoids were characterised, being kaempferol-3- O -neohesperidoside the major compound, besides others in trace amounts. These include quercetin, kaempferol and isorhamnetin glycosides, with several of them being isomers. Acetylated derivatives are also described. This is the first time that non-coloured flavonoids are reported from this pollen, with MS fragmentation proving to be most useful in the elucidation of isomeric structures. Copyright © 2010 John Wiley & Sons, Ltd. [source] Characterization of phenolic compounds in the Chinese herbal drug Tu-Si-Zi by liquid chromatography coupled to electrospray ionization mass spectrometry,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2005Min Ye Phenolic compounds are the major bioactive constituents of the Chinese herbal drug Tu-Si-Zi, which is prepared from the seeds of Cuscuta chinensis. However, seeds of C. australis also are offered under the name of this drug in the herb market. In order to make a comparison of their chemical constituents, the phenolic compounds of these two Cuscuta species were analyzed by high-performance liquid chromatography/diode-array detection/electrospray ion trap tandem mass spectrometry (HPLC/DAD/ESI-MSn). A total of 50 compounds were observed in the methanol extracts, including 23 flavonoids, 20 lignans and 7 quinic acid derivatives. These compounds were separated on a C18 column and identified or tentatively characterized based on UV spectra and MS fragmentation behavior. In contrast to previous reports, the phenolic patterns of these two Cuscuta species were found to be very different. Kaempferol and astragalin were the predominant constituents of C. australis, while hyperoside was the major compound in C. chinensis. Most of the identified compounds, especially the acylated flavonoid glycosides, have not previously been reported from Cuscuta species. In addition, a 30,Da neutral loss observed for flavonols was investigated and could be used to differentiate flavonoid isomers such as kaempferol and luteolin. The ESI-MS fragmentation behavior of furofuran lignans was also investigated, and a characteristic pathway is proposed. The large differences observed between the phenolic constituents of C. chinensis and C. australis strongly encouraged further comparison of the bioactivities of these two species. Copyright © 2005 John Wiley & Sons, Ltd. [source] Organoarsenic compounds in plants and soil on top of an ore veinAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 5 2002Anita Geiszinger Abstract Plants and soil collected above an ore vein in Gasen (Austria) were investigated for total arsenic concentrations by inductively coupled plasma mass spectrometry (ICP-MS). Total arsenic concentrations in all samples were higher than those usually found at non-contaminated sites. The arsenic concentration in the soil ranged from ,700 to ,4000,mg kg,1 dry mass. Arsenic concentrations in plant samples ranged from ,0.5 to 6,mg kg,1 dry mass and varied with plant species and plant part. Examination of plant and soil extracts by high-performance liquid chromatography,ICP-MS revealed that only small amounts of arsenic (<1%) could be extracted from the soil and the main part of the extractable arsenic from soil was inorganic arsenic, dominated by arsenate. Trimethylarsine oxide and arsenobetaine were also detected as minor compounds in soil. The extracts of the plants (Trifolium pratense, Dactylis glomerata, and Plantago lanceolata) contained arsenate, arsenite, methylarsonic acid, dimethylarsinic acid, trimethylarsine oxide, the tetramethylarsonium ion, arsenobetaine, and arsenocholine (2.5,12% extraction efficiency). The arsenic compounds and their concentrations differed with plant species. The extracts of D. glomerata and P. lanceolata contained mainly inorganic arsenic compounds typical of most other plants. T. pratense, on the other hand, contained mainly organic arsenicals and the major compound was methylarsonic acid. Copyright © 2002 John Wiley & Sons, Ltd. [source] A novel heat-shock protein coinducer boosts stress protein Hsp70 to activate T cell regulation of inflammation in autoimmune arthritisARTHRITIS & RHEUMATISM, Issue 4 2010Lotte Wieten Objective Stress proteins, such as members of the heat-shock protein (HSP) family, are up-regulated by cells in inflamed tissue and can be viewed functionally as "biomarkers" for the immune system to monitor inflammation. Exogenous administration of stress proteins has induced immunoregulation in various models of inflammation and has also been shown to be effective in clinical trials in humans. This study was undertaken to test the hypothesis that boosting of endogenous HSP expression can restore effective immunoregulation through T cells specific for stress proteins. Methods Stress protein expression was manipulated in vivo and in vitro with a food component (carvacrol), and immune recognition of stress proteins was studied. Results Carvacrol, a major compound in the oil of many Origanum species, had a notable capacity to coinduce cellular Hsp70 expression in vitro and, upon intragastric administration, in Peyer's patches of mice in vivo. As a consequence, carvacrol specifically promoted T cell recognition of endogenous Hsp70, as demonstrated in vitro by the activation of an Hsp70-specific T cell hybridoma and in vivo by amplified T cell responses to Hsp70. Carvacrol administration also increased the number of CD4+CD25+FoxP3+ T cells, systemically in the spleen and locally in the joint, and almost completely suppressed proteoglycan-induced experimental arthritis. Furthermore, protection against arthritis could be transferred with T cells isolated from carvacrol-fed mice. Conclusion These findings illustrate that a food component can boost protective T cell responses to a self stress protein and down-regulate inflammatory disease, i.e., that the immune system can respond to diet. [source] Supercritical CO2 Extraction of Essential Oil from Algerian Rosemary (Rosmarinus officinalis,L.)CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 3 2010A. Zermane Abstract The present study presents experimental results concerning the supercritical CO2 extraction of essential oil from Algerian rosemary leaves. The effects of key operating parameters such as pressure, temperature, particle size and CO2 mass flow rate on the extraction yield were investigated. The obtained yields were in the range of 0.95,3.52,g oil/g dry rosemary, and the best value was observed at a pressure of 22,MPa, a temperature of 40,°C, a flow rate of 7,g/min, and a particle size of 1,mm. The performance of the local rosemary used was assessed by comparison of the obtained yields with values reported in the literature for essential oils derived from different rosemary sources. The GC and the GC-MS analyses showed that the major compound detected in the essential oil was camphor, at 48.89,wt,%. [source] Composition of the essential oil of Teucrium ramosissimum Desf. (Lamiaceae) from TunisiaFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2007Souleima F. Hachicha Abstract The essential oil from aerial parts of Teucrium ramosissimum Desf. (Lamiaceae), endemic to North Africa, was isolated by steam distillation and analysed by gas chromatography (GC) and gas chromatography,mass spectrometry (GC,MS). Seventy-four components were identified; the essential oil was mainly composed of sesquiterpene hydrocarbons and oxygenated sesquiterpenes at nearly the same amounts (41.9% and 42.3%, respectively). , -Cadinene (19.97%), , -cadinol (9.93%) and germacradien-4- , -1-ol (8.68%) were the major compounds. Copyright © 2007 John Wiley & Sons, Ltd. [source] Essential oil composition of Pimpinella aurea D.C. from IranFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005F. Askari Abstract Essential oils were isolated by hydrodistillation from the stems, ,owers and seeds of Pimpinella aurea D.C. They were collected individually from Fasham (north-west of Tehran province). The yields of stem + leaf, ,ower and seed oils were 0.4%, 1.5% and 2.0% w/w, respectively; 32 constituents were identi,ed in the stem + leaf oil, 18 in the ,ower oil and eight in the seed oil. Major constituents of the stem + leaf oil were: 1,8-cineol and limonene (21.4%), viridi,orol (12.8%), , -pinene (11.5%), kessane (10.5%), germacrene D (4.9%), , -bisabolene (4.2%), , -zingiberene (3.3%) and citronellyl acetate (3.1%). Major constituents of the ,ower oil were: viridi,orol (32.5%), , -bisabolene (29.5%), caryophyllene oxide (6.6%), 1,8-cineol + limonene (8.9%) and estragol (5.1%). Major constituents of the seed oil were: , -bisabolene (50.8%), and viridi,orol (37.0%). Three compounds (, -bisabolene, viridi,orol and caryophyllene oxide) were common to all three oils. 1,8-Cineol and limonene, kessane and , -pinene were the major compounds in the stem + leaf and ,ower oils but were not found in the seed oil. Copyright © 2004 John Wiley & Sons, Ltd. [source] Volatile oils from leaves and stem barks of Cedrela ,ssilis (Meliaceae): chemical composition and antibacterial activitiesFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2004João Henrique G. Lago Abstract The volatile oils from the leaves and stem barks of Cedrela ,ssilis were submitted to GC,MS analysis and separation by adsorption chromatography. The fractions were analysed by GC, 1H- and 13C-NMR as well as GC,MS. The major components found in the leaf oil were , -caryophyllene (26.3%) and bicyclogermacrene (34.6%), while in the stem bark oil the major compounds were , -bisabolene (10.9%) and globulol (10.9%). In an antibacterial assay, only the leaf oil was able to inhibit growth of Staphylococcus aureus and Eschorichia coli. Copyright © 2004 John Wiley & Sons, Ltd. [source] Ralstonia pickettii in environmental biotechnology: potential and applicationsJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2007M.P. Ryan Summary Xenobiotic pollutants such as toluene and trichloroethylene are released into the environment by various industrial processes. Ralstonia pickettii possess significant biotechnological potential in the field of bioremediation and has demonstrated the ability to breakdown many of these toxic substances. Here, we provide a description of the major compounds that various strains of R. pickettii are capable of degrading and a brief review of their breakdown pathways and an argument for its use in bioremediation. [source] APPLICATION OF ULTRASONICATION OR HIGH-PRESSURE EXTRACTION OF FLAVONOIDS FROM LITCHI FRUIT PERICARPJOURNAL OF FOOD PROCESS ENGINEERING, Issue 6 2009K. NAGENDRA PRASAD ABSTRACT Litchi (Litchi chinensis Sonn.) fruit pericarp (LFP) contains a high amount of flavonoids, which could be used as natural antioxidants. Some emerging novel technologies, such as ultrasonic extraction (UE) and high-pressure extraction (HPE), have exhibited great potential for flavonoid extraction. Experiments were conducted to comparatively investigate the effects of conventional extraction (CE), 40-KHz UE and 200- or 400-MPa HPE on the extraction efficiency of flavonoids from LFP. After 30 min of extraction, the extract yield, total phenolic content, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and superoxide anion scavenging ability were examined. The crude extract yields by the UE, 400 HPE and CE were 24, 30 and 1.83%, respectively. However, there were no significant differences (P > 0.05) in the total phenolic content and antioxidant activity tested among these three different extractions at the same concentration. In addition, two flavonoids, namely epicatechin and epicatechin gallate, were identified and quantified as the major compounds, while catechin and procyanidin B2 were identified as the minor compounds. The total flavonoid content detected was 0.65, 0.75, 0.29 and 0.07 mg/g dry weight by HPE at 200 and 400 MPs, UE, and CE, respectively. Thus, the HPE technique showed a higher efficiency in extracting flavonoids from LFP, and the HPE could reduce the extraction time and increase the amount of the extracted phenolics. PRACTICAL APPLICATIONS Litchi (Litchi chinensis Sonn.) is a subtropical fruit that originated in Southeast Asia. As litchi fruit is gradually accepted by consumers for its delicious taste and attractive red skin, litchi production has steadily increased in recent decades, with increasing exports to Europe and North America from both the southern and northern hemisphere production areas. Litchi fruit pericarp (LFP) accounts for approximately 16% by weight of the whole fresh fruit and is comprised of a significant amount of flavonoids. Therefore, LFP tissues may be considered an important source of dietary flavonoids. This work showed that HPE technique has a high efficiency in extracting flavonoids from LFP tissues, which may help the litchi industry develop new extraction methods to better utilize the flavonoids from LFP tissues. [source] Influence of Blanching-osmotic Dehydration Treatments on Volatile Fraction of StrawberriesJOURNAL OF FOOD SCIENCE, Issue 7 2000I. Escriche ABSTRACT: The effects of steam (S) and microwave (MW) blanching and osmotic treatments, applied either singularly or combined, on the volatile fraction of strawberry have been evaluated. Osmotic dehydration was carried out at atmospheric conditions (OD) and by applying a vacuum pulse at the beginning of the process (PVOD). Volatiles were obtained by a simultaneous distillation-extraction procedure and identified/quantified by gas chromatography-mass spectrometry. Esters and 2,5-dimethyl-4-hydroxy-3(2H)-furanone were the major compounds. Differences in volatile concentration promoted by blanching and/or osmotic processes were evaluated. Osmotic treatments promote formation of esters and furanones, differently for either OD or PVOD treatments, but this effect was greatly inhibited when osmosis was preceded by blanching. The kind of blanching (MW or S) also affected the sample final volatile profile. [source] Hypericum perforatum,Chemical profiling and quantitative results of St. John's Wort products by an improved high-performance liquid chromatography methodJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 3 2002M. Ganzera Abstract The analysis of flavonoids, naphthodianthrones, and the phloroglucinol derivative hyperforin in H. perforatum is described in this article. In a 35-min HPLC run nine major compounds could be identified and baseline separated in the methanolic plant extracts. For an optimum separation the mobile phase consisted of 10 mM ammonium acetate buffer (pH 5.0) and an acetonitrile/methanol mixture; a Synergi MAX-RP 80 Å column (C-12 material) was used as stationary phase. Detection was performed at 270 nm, and the identity of the compounds was confirmed in an LC-MS experiment. Commercial St. John's Wort products were analyzed and qualitative and quantitative results are discussed. © 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:623,630, 2002 [source] Antifungal activity of Thymus oils and their major compoundsJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 1 2004C Pina-Vaz ABSTRACT The increasing recognition and importance of fungal infections, the difficulties encountered in their treatment and the increase in resistance to antifungals have stimulated the search for therapeutic alternatives. Essential oils have been used empirically. The essential oils of Thymus (Thymus vulgaris, T. zygis subspecies zygis and T. mastichina subspecies mastichina) have often been used in folk medicine. The aim of the present study was to evaluate objectively the antifungal activity of Thymus oils according to classical bacteriological methodologies , determination of the minimal inhibitory concentration (MIC) and the minimal lethal concentration (MLC) , as well as flow cytometric evaluation. The effect of essential oils upon germ tube formation, an important virulence factor, was also studied. The mechanism of action was studied by flow cytometry, after staining with propidium iodide. The chemical composition of the essential oils was investigated by gas chromatography (GC) and gas chromatography/mass spectroscopy (GC/MS). The antifungal activity of the major components (carvacrol, thymol, p -cymene and 1,8-cineole) and also possible interactions between them were also investigated. The essential oils of T. vulgaris and T. zygis showed similar antifungal activity, which was greater than T. mastichina. MIC and MLC values were similar for all the compounds tested. At MIC values of the essential oils, propidium iodide rapidly penetrated the majority of the yeast cells, indicating that the fungicidal effect resulted primarily from an extensive lesion of the cell membrane. Concentrations below the MIC values significantly inhibited germ tube formation. This study describes the potent antifungal activity of the essential oils of Thymus on Candida spp., warranting future therapeutical trials on mucocutaneous candidosis. [source] 1H-HRMAS NMR study of smoked Atlantic salmon (Salmo salar)MAGNETIC RESONANCE IN CHEMISTRY, Issue 9 2010David Castejón Abstract High-resolution magic angle spinning (HRMAS) NMR spectroscopic data of smoked Atlantic salmon (Salmo salar) were fully assigned by combination of one- and two-dimensional-HRMAS experiments. Complete representative spectra, obtained after few minutes of analysis time, revealed a large number of minor and major compounds in the sample. The methodology is limited by the low sensitivity of NMR, and therefore HRMAS only enables the determination of the most relevant components. These were fatty acids (FAs), carbohydrates, nucleoside derivatives, osmolytes, amino acids, dipeptides and organic acids. For the first time, spectra were resolved sufficiently to allow semiquantitative determination in intact muscle of the highly polyunsaturated FA 22:6 ,-3. Additionally, the feasibility of 1H-HRMAS NMR metabolite profiling was tested to identify some bioactive compounds during storage. This profiling was carried out by the non-destructive and direct analysis (i.e. without requiring sample preparation and multiple step procedures) of intact salmon muscle. The proposed procedure can be applied to a large number of samples with high throughput due to the short time of analysis and quick evaluation of the data. Copyright © 2010 John Wiley & Sons, Ltd. [source] DOSY NMR applied to analysis of flavonoid glycosides from Bidens sulphureaMAGNETIC RESONANCE IN CHEMISTRY, Issue 12 2009Edilene Delphino Rodrigues Abstract 2D DOSY 1H NMR has proved to be a useful technique in the identification of the molecular skeleton of the four major compounds of ethyl acetate extract of aerial parts of Bidens sulphurea (Asteraceae). The combination of this technique with HPLC, mass spectrometry and other NMR techniques enabled the identification of four flavonoid glycosides: quercetin-3- O -,- D -galactopyranoside, quercetin-3- O -,- D -glycopyranoside, quercetin-3- O -,- L -arabinofuranoside and quercetin-3- O -,- D -rhamnopyranoside. Copyright © 2009 John Wiley & Sons, Ltd. [source] Total antioxidant capacity and content of flavonoids and other phenolic compounds in canihua (Chenopodium pallidicaule): An Andean pseudocerealMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 6 2008J. Mauricio Peñarrieta Abstract Total antioxidant capacity (TAC), total phenolic compounds (TPH), total flavonoids (TF) and individual phenolic compounds were determined in canihua collected at approx. 3850 m altitude. The TAC values varied among samples from 2.7 to 44.7 by the ferric reducing antioxidant power (FRAP) method and from 1.8 to 41 by the 2,2,-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) method expressed as ,mol of Trolox equivalents/g dw. The content of TPH was 12.4,71.2 ,mol gallic acid equivalents/g dw and that of the TF ranged between 2.2 and 11.4 ,mol of catechin equivalents/g dw. The data obtained by the four methods showed several significant correlations. Prior to analysis by HPLC, the samples were subjected to acid hydrolysis and in the water-soluble extracts this led to an up to 20-fold increase in the TAC values in comparison with the values of the nonhydrolysed samples. HPLC analysis showed the presence of eight major compounds identified as catechin gallate, catechin, vanillic acid, kaempferol, ferulic acid, quercetin, resorcinol and 4-methylresorcinol. Their estimated contribution to the TAC value (FRAP method) indicated that resorcinols contributed most of the antioxidant capacity of the water-soluble extract. The results show that canihua is a potential source of natural antioxidant compounds and other bioactive compounds which can be important for human health. [source] Insecticidal activity of 23 essential oils and their major compounds against adult Lipaphis pseudobrassicae (Davis) (Aphididae: Homoptera)PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 11 2005Blair J Sampson Abstract Essential oils from 23 species of plants comprising 14 genera and 4 plant families were obtained by Clevenger-type water distillation. The major compounds in these essential oils were identified with GC-MS and their insecticidal activity against adult turnip aphids, Lipaphis pseudobrassicae (Davis), tested with dosage-mortality bioassays. We examined mortality only for viviparous adults because sizeable aphid populations on crucifer (Brassicaceae) hosts are largely produced by these wingless, parthenogenic females. Twenty-two of the oils were directly applied to aphid females in randomized blocks at concentrations of 0.0, 1.0, 2.5, 5.0 and 10.0 mg ml,1. Essential oils mixed with a non-toxic emulsifying agent, dimethyl sulfoxide (DMSO), more easily penetrated the waxy insect cuticle. Probit analysis and LC50 at three different exposures showed aphids were quickly incapacitated and killed by aliphatic aldehydes, phenols and monocyclic terpenes contained in Bifora and Satureja oils and at applied concentrations as low as 0.3 to 1.0 mg ml,1. Only enough Pimpinella isaurica oil and its three phenylpropanoid fractions were available for testing at a single concentration of 10 mg ml,1. We could not spare any additional P. isaurica oil for testing at other concentrations. Phenylpropanoids isolated from P. isaurica oil when recombined or left naturally blended in the oil were highly bioactive against L. pseudobrassicae at 10 mg ml,1. Copyright © 2005 Society of Chemical Industry [source] High-performance liquid chromatography with diode array detection coupled to electrospray time-of-flight and ion-trap tandem mass spectrometry to identify phenolic compounds from a Cistus ladanifer aqueous extractPHYTOCHEMICAL ANALYSIS, Issue 4 2010S. Fernández-Arroyo Abstract Introduction , Cistus ladanifer is an aromatic shrub that is widespread in the Mediterranean region. The labdanum exudate is used in the fragrance industry and has been characterised. However, there is not enough information about the phenolic content of the raw plant, the aerial part of it being a very rich source of bioactive compounds. Objective , Characterisation of the bioactive compounds of the raw plant and its aerial parts. Methodology , High-performance liquid chromatography with diode array and electrospray ionisation mass spectrometric detection was used to carry out the comprehensive characterisation of a Cistus ladanifer shrub aqueous extract. Two different MS techniques were coupled to HPLC: time-of-flight mass spectrometry and tandem mass spectrometry. Results , Many well-known compounds present in Cistus ladanifer were characterised, such as flavonoids, phenolic acids, ellagitanins, hexahydroxydiphenoyl and derivatives, and other compounds. Conclusion , The method described simultaneously separated a wide range of phenolic compounds and the proposed characterisation of the major compounds of this extract was carried out. It is important to highlight that, to our knowledge, this is the first time that a Cistus ladanifer aqueous extract from the raw plant has been characterised. Copyright © 2009 John Wiley & Sons, Ltd. [source] Selective ultrasound-assisted extractions of lipophilic constituents from Betula alleghaniensis and B. papyrifera wood at low temperaturesPHYTOCHEMICAL ANALYSIS, Issue 4 2007J.-M. Lavoie Abstract Betula alleghaniensis and B. papyrifera are widely distributed in the province of Québec (Canada) and, since these trees are valuable exports for the local lumber industry, large amounts of their residual ligneous biomass are available for further exploitation. Betula species are well known for their significant concentrations of triterpenes, some of which were recently discovered to present promising bioactivity. The secondary transformation of birch biomass could therefore become important for many industries, particularly the pharmaceutical industry. In the present study, extracts from birch sawdust were obtained using an optimised ultrasound-assisted extraction in which the careful choice of temperature permitted a selective extraction of the targeted triterpenes. Moreover, compared with the classical Soxhlet method, higher extraction yields were obtained in a shorter time. The lipophilic extracts obtained using dichloromethane as a solvent were analysed by GC-MS and the major compounds identified as lupane-type cyclic triterpenoids accompanied by the non-cyclic triterpene squalene. Numerous aliphatic long-chain fatty acids were also found in the extracts together with phytosterols. Betulonic acid and squalene, the major extract constituents for both B. alleghaniensis and B. papyrifera, are both bioactive molecules. Copyright © 2007 John Wiley & Sons, Ltd. [source] The phytochemical profile and identification of main phenolic compounds from the leaf exudate of Aloe secundiflora by high-performance liquid chromatography,mass spectroscopyPHYTOCHEMICAL ANALYSIS, Issue 2 2003Waihenya Rebecca Abstract The phytochemical profile of Aloe secundiflora (Aloeaceae) and the identity of eight major compounds, including the two main constituents, have been determined from the leaf exudate of this ethnoveterinary used species from Kenya and Tanzania. Analytical HPLC-MS studies of the exudate have revealed that it comprises a mixture of phenolic compounds, mainly anthrones (aloenin, aloenin B, isobarbaloin, barbaloin and other aloin derivatives), chromones and phenylpyrones with a low content of polysaccharides and aliphatic compounds. The high percentage of anthrones in the exudate could provide a first line of evidence for the use of the plant in ethnoveterinary practices. Copyright © 2003 John Wiley & Sons, Ltd. [source] Antioxidant activity of Plantago bellardii All.PHYTOTHERAPY RESEARCH, Issue 12 2005Marina Gálvez Abstract The aim of this study was to evaluate the in vitro antioxidant activity of the methanol extract of Plantago bellardii All. aerial parts. This was assessed by two different tests, scavenging of 1,1-diphenyl-2-picrylhydrazil (DPPH) radical, and inhibition of lipid peroxidation on liposomes prepared from bovine brain extract. In both tests the extract showed a potent antioxidant effect. The characterization of the major compounds in the extract as rutin, geniposide and verbascoside was performed by isolation and HPLC comparison with authentic samples. They were quantified by HPLC for the flavonoids and colorimetry for iridoids. The compounds that contribute most to the antioxidant activity were shown to be verbascoside and rutin. Copyright © 2005 John Wiley & Sons, Ltd. [source] In vivo and in vitro activities of the seed extract of Piper guineense Schum. and Thonn. against skin and gill monogenean parasites of gold,sh (Carassius auratus auratus)PHYTOTHERAPY RESEARCH, Issue 10 2004A. P. Ekanem Abstract Methanol extracts of the seeds of Piper guineense (Piperaceae) were active against gold,sh (Carassius auratus auratus L. Pisces Cyprinidae) monogenean parasites. The seed extract of P. guineense was administered at different concentrations (0.5,2.0 mg/L) under in vivo and in vitro conditions. There was a higher ef,cacy of the effects of the extracts against ,sh parasites under in vitro situations than under in vivo. Three major compounds (piperanine, N -isobutyl (E,E)-2,4 decadienamide and ,,,, -dihydrowasanine) were identi,ed from the seed extract of Piper guineense by LC-MS analysis. Copyright © 2004 John Wiley & Sons, Ltd. [source] High-speed separation and characterization of major constituents in Radix Paeoniae Rubra by fast high-performance liquid chromatography coupled with diode-array detection and time-of-flight mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 1 2009E-Hu Liu A fast high-performance liquid chromatography (HPLC) method coupled with diode-array detection (DAD) and electrospray ionization time-of-flight mass spectrometry (ESI-TOFMS) has been developed for rapid separation and sensitive identification of major constituents in Radix Paeoniae Rubra (RPR). The total analysis time on a short column packed with 1.8-µm porous particles was about 20,min without a loss in resolution, six times faster than the performance of a conventional column analysis (115,min). The MS fragmentation behavior and structural characterization of major compounds in RPR were investigated here for the first time. The targets were rapidly screened from RPR matrix using a narrow mass window of 0.01,Da to restructure extracted ion chromatograms. Accurate mass measurements (less than 5,ppm error) for both the deprotonated molecule and characteristic fragment ions represent reliable identification criteria for these compounds in complex matrices with similar if not even better performance compared with tandem mass spectrometry. A total of 26 components were screened and identified in RPR including 11 monoterpene glycosides, 11 galloyl glucoses and 4 other phenolic compounds. From the point of time savings, resolving power, accurate mass measurement capability and full spectral sensitivity, the established fast HPLC/DAD/TOFMS method turns out to be a highly useful technique to identify constituents in complex herbal medicines. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||