bluuebunny/crossref_metadata_2025_split huggingface dataset:
High resolution gas chromatography—Mass spectral analysis of carbohydrates using methoxyoxime acetates
Authors: Herderich Markus , Schreier Peter 
Published: March 2007

AbstractMethoxyoxime acetates of carbohydrates and partially methylated derivatives were easily separated by high resolution gas chromatography (HRGC) and showed characteristic mass spectra (MS). Thus, the conversion of carbohydrates to the corresponding methoxyoxime acetates offers an attractive derivatization for subsequent HRGC and HRGC/MS analysis of carbohydrates, particularly in glycoconjugates of plant origin.
Quantitation of bilobalide and ginkgolides A, B, C and J by means of nuclear magnetic resonance spectroscopy
Authors: van Beek Teris A. , van Veldhuizen Albertus , Lelyveld Gerrit P. , Piron Isabelle , Lankhorst Peter P. 
Published: March 2007

AbstractA quantitative 1H NMR procedure for the determination of bilobalide and ginkgolides A, B, C and J in Ginkgo biloba leaves and in phytopharmaceuticals without prior chromatographic separation of the mixture has been developed. The method is based on the comparison of the integral of each H‐12 proton of the five ginkgo terpene trilactones with that of the olefinic protons of the internal standard (maleic acid). These protons are all well separated at 200 MHz and occur in a less crowded region of the NMR spectrum (6.15‐6.50 ppm). The selectivity, reproducibility and sensitivity are comparable with high pressure liquid chromatography (HPLC) with refractive index (RI) detection. The minimum amount that can be quantified within 30 min at 200 MHz is approximately 0.1 mg for all four ginkgolides and bilobalide. Advantages, in comparison with HPLC‐RI, are that no reference substances are needed and that for the occasional analysis of a limited number of samples a very significant time‐gain can be achieved.
Alfalfa saponins and sapogenins: Isolation and quantification in two different cultivars
Authors: Tava A. , Oleszek W. , Jurzysta M. , Berardo N. , Odoardi M. 
Published: March 2007

AbstractThe chemical characterization of the saponins and sapogenins isolated from roots and aerial parts of two alfalfa cultivars with differing saponin content is reported. A procedure for the extraction and quantification of saponins is described, and the identification of the major components of the saponin mixture has been performed using thin layer chromatography and high performance liquid chromatography. Characterization, using gas chromatography (GC) and GC/mass spectral analysis, of sapogenins released following acid hydrolysis allowed the identification of medicagenic acid, hederagenin, soyasapogenols B, C, D, E and F as the major compounds, together with oleanolic acid. Quantitative analysis of the sapogenins in aerial parts and roots of the two cultivars is reported and discussed.
Behaviour of polymethoxylated and polyhydroxylated flavones by carbon dioxide supercritical fluid chromatography with flame ionization and fourier transform infrared detectors
Authors: Hadj‐Mahammed M. , Badjah‐Hadj‐Ahmed Y. , Meklati B. Y. 
Published: March 2007

AbstractSome hydroxy‐ and methoxy‐substituted flavones have been studied following carbon dioxide supercritical fluid chromatography on polymethylsiloxane capillary columns using flame ionization and Fourier transform infrared spectroscopic detection. The separation was performed without the use of a phase modifier.
Improved extraction and reversed phase‐high performance liquid chromatographic separation of flavonoids and the identification of Rosa cultivars
Authors: Van Sumere Christiaan , Faché Pierre , Casteele Karel Vande , De Cooman Luc , Everaert Evert , De Loose Roger , Hutsebaut Walter 
Published: March 2007

AbstractOptimal extraction methods and Reversed‐Phase High Performance Liquid Chromatographic (RP‐HPLC) procedures were developed for the isolation and resolution of naturally occurring flavonoids and related phenolic compounds in Rosa petals. The following flavonoids and related phenolics were identified or partly identified: cyanidin 3, 5‐di‐O‐glucoside; cyanidin 3, 5‐di‐O‐glycoside (sugar moieties, glucose and arabinose); pelargonidin 3, 5‐di‐O‐glycoside; pelargonidin 3‐O‐glycoside; quercetin 3‐O‐glucoside; ellagic acid; quercetin 3‐O‐arabinoside; quercetin 4′‐O‐glucoside; kaempferol 4′‐O‐glucoside; kaempferol 3‐O‐rutinoside; kaempferol 3‐O‐glycoside; kaempferol 3‐O‐arabinoside; kaempferol 3‐O‐rhamnoside and kaempferol 3‐O‐glycoside. Significant qualitative and quantitative differences between the above flavonoid markers allowed an objective distinction between 44 cultivars examined. The production of ‘Flower Flavonoid RP‐HPLC Fingerprints’, which have been converted in the corresponding ‘Computer Flower Flavonoid Identity Cards’ via a suitable computer program, has proven to be of great value for Rosa cultivar recognition.
Anomalous behaviour of acidic grapevine peroxidase isoenzymes during preparative isoelectric focusing
Authors: Moralés M. , Pedreño M. A. , Muñoz R. , Barceló A. Ros , Calderón A. A. 
Published: March 2007

AbstractPreparative isoelectric focusing of grapevine peroxidases on glycerol‐stabilized pH gradients in the RotoforTMcell has been used to purify peroxidase isoenzymes from the spent medium of suspension cultured cells derived from mesocarp tissues of grape (Vitis viniferacv. Monastrell) berries. The results showed that, under steady‐state conditions, basic peroxidase isoenzymes focus well while acidic peroxidase isoenzymes show anomalous behaviour during isoelectric focusing, leading to diffuse and/or multiband isoelectric focusing patterns. These results suggest that, although preparative isoelectric focusing in glycerol‐stabilized pH gradients using the Rotofor cell may be a powerful tool for isoenzyme purification, the advantages of this technique may be severely hampered by the anomalous behaviour shown by acidic peroxidase isoenzymes during focusing.
Analysis of poppy straw and poppy straw concentrate by reversed‐phase high‐performance liquid chromatography
Authors: Gómez‐Serranillos P. , Carretero E. , Villar A. 
Published: March 2007

AbstractA method of reversed‐phase high‐performance liquid chromatography using an elution gradient has been developed to analyse morphine, codeine, thebaine, and oripavine — this last‐mentioned substance for the first time — in samples of poppy straw and poppy straw concentrate. Gradient elution of the octadecylsilane column was performed: the gradient was from 10 to 30% of solvent A (methanol) in solvent B (containing 67% of 0.5% aqueous ammonium acetate solution containing diethylamine, and 33% of methanol) over a 25 min period. The four alkaloids were identified and quantified with the aid of an internal standard.
Isolation and quantitation of manogenin and kammogenin from callus cultures of Agave amaniensis
Authors: Indrayanto Gunawan , Studiawan Herra , Cholies Noor 
Published: March 2007

AbstractManogenin and its Δ5(6) derivative kammogenin were isolated from the acid hydrolysate extract of Agave amaniensis callus cultures. A method for the quantitative determination of manogenin and kammogenin by thin layer chromatography was developed.
Phenylpropanoid metabolism in Vanilla planifolia Andr. (V) high performance liquid chromatographic analysis of phenolic glycosides and aglycones in developing fruits
Authors: Brodelius Peter E. 
Published: March 2007

AbstractReversed‐phase high performance liquid chromatography (HPLC) has been used to study the formation of phenolic flavour compounds in developing fruits of Vanilla planifolia. Flowers of V. planifolia were hand pollinated and fruits were collected at 12 different times (4 to 28 weeks) after pollination at a vanilla plantation in Papantla, Veracruz, Mexico. HPLC‐chromatograms of bean extracts were recorded at two wavelengths (254 and 275 nm) and the ratio between the absorbances of these chromatograms was used in combination with retention times to identify phenolics in the relatively complex extracts. Formation of vanillin, the major flavour compound, started around 16 weeks after pollination and reached maximum values around 26 weeks after pollination. Other phenolic vanilla flavour components detected were 4‐hydroxybenzaldehyde, 4‐hydroxybenzoic acid, vanillyl alcohol and vanillic acid. All these phenolics are stored in bean tissue mainly as glycosides.
Quantitative thin layer chromatography of iridoid and flavonoid glucosides in species of Linaria
Authors: Nikolova‐Damyanova Boryana , Ilieva Emilia , Handjieva Nedjalka , Bankova Yassya 
Published: March 2007

AbstractA method for the quantitative determination of iridoid and flavonoid glucosides in Linaria species has been developed. Four iridoid glucosides‐antirrinoside, linarioside, 5‐O‐glucosylantirrinoside and 5‐O‐allosylantirrinoside ‐ as well as the flavonoid acetylpectolinarin, could be determined in four species of Linaria on a single thin layer chromatographic plate in the presence of two external standards.
Determination of the natural deuterium distribution in glucose from plants having different photosynthetic pathways
Authors: Zhang Ben‐Li , Quemerais Bernadette , Martin Maryvonne L. , Martin Gérard J. , Williams J. Michael 
Published: March 2007

AbstractThe site‐specific natural isotope fractionation of hydrogen in glucose was investigated by nuclear magnetic resonance spectroscopy (SNIF‐NMR). Several glucose samples obtained from plants undergoing either C3 (potato, barley, sunflower, wheat) or C4 (maize, sorghum) photosynthetic metabolism were investigated. Since the glucose molecule is not suitable for direct SNIF‐NMR analysis, several kinds of derivatives were synthesized. Three clusters of isotopomers were identified in glucose penta‐acetate which is easily prepared. Up to 5–6 sites could be distinguished in 6 other derivatives. An integrated statistical analysis of the whole sets of cluster lines was performed in order to determine the individual isotope contents in the carbon‐bound hydrogen positions of the glucose skeleton. Both the mole fractions of the monodeuterated isotopomers and the deuterium/hydrogen ratios of the individual sites thus become accessible. Using this approach, it is shown that similar trends in the isotopic distribution are exhibited within a given photosynthetic C3 or C4 family. Larger deviations with respect to a statistical distribution of deuterium are observed in glucose from C3 plants as compared to C4 plants. The methylenic sites 6,6′ in particular are significantly depleted in C3 glucose as compared to C4 glucose.
Separation of flavonols by capillary electrophoresis: The effect of structure on electrophoretic mobility
Authors: McGhie Tony K. , Markham Kenneth R. 
Published: March 2007

AbstractThe electrophoretic mobilities of 33 flavonol aglycones and glycosides have been measured to determine the structural factors which influence capillary electrophoretic separation. Factors primarily responsible for differences in electrophoretic mobility (EM) in flavonols are: the molecular size; the number and position of the free OH groups on the flavonol skeleton; the number, type and position of attached sugar groups; and the presence of ionizable moieties such as sulphate and phenolic acyl groups. Some structural features of flavonols have a dual effect on electrophoretic mobility. Higher levels of glycosylation, for example, result in increased molecular size and in a lesser number of ionizable phenolic hydroxyl groups, both of which decrease EM. The data presented provide a basis for predicting relative EMs of flavonols and their glycosides.
Extraction of coumarins from plant material (Leguminosae)
Authors: Bourgaud F. , Poutaraud A. , Guckert A. 
Published: March 2007

AbstractSeven different methods for the extraction of coumarin and corresponding glycosides from Melilotus officinalis L. and furanocoumarins (psoralen and angelicin) from Psoralea cinerea Lindl. were compared. In the case of coumarins, extraction with polar solvents (water, ethanol, methanol) was shown to be the most efficient: water extraction gave the highest total coumarin concentration, especially for the major component β‐D‐glucosyl cis‐O‐hydroxycinnamic acid. Free coumarin could also be recovered in large quantity when the extraction was performed with water at room temperature instead of at 100°C. Ethyl acetate, diethyl ether and chloroform extracted the free coumarin poorly and the glycosides hardly at all. In the case of furanocoumarins, the best results were obtained with boiling methanol using either Soxhlet extraction or refluxed solvent. Other extraction methods involving water, methanol at room temperature, ethyl acetate or chloroform gave essentially similar results. Diethyl ether was the least satisfactory in terms of furanocoumarin concentration, whilst water extraction of furanocoumarins is of particular interest because the extracted quantities can be easily correlated with the methanol method.
Determination of morphological group from infrared spectra of crude extracts of medicinal plants by SIMCA pattern recognition
Authors: Zhang Liang , Ying Han , Zhang Zheng‐Xing , Sheng Long‐Sheng , An Deng‐Kui 
Published: March 2007

AbstractThis paper reports a new method of classification and identification of medicinal plants by pattern recognition within the infrared spectra of crude extracts. The spectra of solvent extracts of 29 samples of Tripterygium wilfordii and T. hypoglaucum were examined for information concerning chemical classes. The Shannon information content for each wavelength channel was calculated for the absorption spectra, and the 9 wavelength channels with the highest information content were retained as a compressed basis set for SIMCA pattern recognition. The inherent class structure of the data showed two major groups, T. wilfordii root and T. wilfordii bark. Classification accuracy was 95.0% for the classes.
Structure determination of acylated anthocyanins in Muscat Bailey a grapes by homonuclear Hartmann‐Hahn (HOHAHA) spectroscopy and liquid chromatography‐mass spectrometry
Authors: Tamura Hirotoshi , Hayashi Yoshiki , Sugisawa Hiroshi , Kondo Tadao 
Published: March 2007

AbstractThe stereochemical structure of acylated anthocyanins in the Japanese grape, Muscat Bailey A, was determined by homonuclear Hartmann‐Hahn (HOHAHA) spectroscopy and liquid chromatography‐mass spectrometry. The structures found were peonidin 3‐O‐(6‐O‐(trans‐p‐coumaroyl)‐β‐D‐glucopyranoside), delphinidin 3‐O‐(6‐O‐(trans‐p‐coumaroyl)‐β‐D‐glucopyranoside), malvidin 3‐O‐(6‐O‐(trans‐p‐coumaroyl)‐β‐D‐glucopyranoside), and malvidin 3‐O‐(6‐O‐(trans‐p‐coumaroyl)‐β‐D‐glucopyranoside)‐5‐O‐D‐glucopyranoside.
Analysis of the fungicidal constituents from the bark of Ocotea usambarensis Engl. (Lauraceae)
Authors: Terreaux Christian , Maillard Marc , Hostettmann Kurt , Lodi Gaetano , Hakizamungu Etienne 
Published: March 2007

AbstractThe dichloromethane extract of the bark of Ocotea usambarensis Engl. (Lauraceae) showed antifungal activity against Cladosporium cucumerinum. This activity was shown to be linked with its essential oil content together with the presence of the lignan (+)‐piperitol. Gas chromatography‐mass spectrometric (GC‐MS) analysis of the oil allowed the identification of about seventy compounds. In order to determine the fungicidal active components of the oil, further separation was required. Instrumental preparative thin layer chromatography (TLC) was chosen because it was a very suitable method to be followed by direct bioautography.Analysis of the fractions by GC‐MS combined with instrumental bidimensional TLC and direct bioautography allowed the separation and identification of the four main active compounds. Nerolidol, α‐terpineol, α‐copaen‐ 11‐ol and a further unidentified sesquiterpene alcohol were shown to be fungicidal. Identification was made by comparison of the mass spectra with a computerised data‐bank and the literature, together with the comparison of retention indices on two GC columns with literature values and with some commercially available samples.
Phytic acid content of three legumes in the raw, cooked and fibre forms
Authors: Elhardallou Sirelkhatim B. , Walker Ann F. 
Published: March 2007

AbstractPhytate was extracted on an anion‐exchange column and determined colorimetrically. More phytate could be extracted from beans using trichloroacetic acid and warming at 60°C than by using hydrochloric acid extraction. The phytic acid contents of three starchy legumes, namely butter beans, broad beans and lentils, in the raw forms were found to be in the range 0.86–1.5%. On cooling, phytic acid was reduced markedly in lentils and butter beans (by 60 and 50%, respectively), while for broad beans only 11% was lost. The fibre‐rich fractions of the three legumes showed low phytic acid contents (0.11–0.43%).
A comparative study of the O‐phthalaldehyde method for the neurotoxin 3‐N‐oxalyl‐l‐2,3‐diaminopropanoic acid as modified by various laboratories
Authors: Hussain M. , Chowdhurry B. , Haque R. , Wouters G. , Campbell C. G. 
Published: March 2007

AbstractThe optimization of the quantitative photometric estimation of the neurotoxin 3‐N‐oxalyl‐L‐2,3‐diaminopropanoic acid (ODAP) after hydrolysis and reaction with o‐phthalaldehyde (OPT) reagent is described.Six modifications of the OPT procedure (as practiced in different laboratories) and the original Rao method were compared in estimating the ODAP content of two cultivars of Lathyrus sativus. Considerable variation in the ODAP content of the same sample was observed even when determined by the same procedure in some cases. The desired reproducibility was observed with the procedure of the Agriculture Canada Research Station, Mordsen, Manitoba, Canada (Campbell method). The use of 0.5 M tetraborate as buffer further significantly improves the reproducibility. The Campbell modification includes a number of controls which reduce variation. The present study recommends the Campbell modification of the OPT method but with tetraborate buffer as standard procedure for the screening of the toxicity of L. sativus cultivars.
Capillary electrophoretic analyses of alkaloids in commercial samples of Coptidis Rhizoma
Authors: Liu Ying‐Mei , Sheu Shuenn‐Jyi , Chiou Shiow‐Hua , Chang Hsien‐Chang , Chen Yuh‐Pan 
Published: March 2007

AbstractA total of 32 samples of commercial Coptidis Rhizoma derived from Coptis chinensis Franch, C. deltoidea C.Y. Cheng et Hsiao, C. japonica (Thunb.) Makino and C. japonica Makino var. dissecta Nakai were collected from herb markets in Taiwan and Japan. The contents of the eight quaternary alkaloids, namely coptisine, berberine, epiberberine, palmatine, columbamine, berberastine, jatrorrhizine and magnoflorine, in these samples were determined by capillary electrophoresis. It was found that the total alkaloid contents in C. chinensis (11.95 ± 1.79%) and C. deltoidea (12.93 ± 1.26%) were far higher than in C. japonica (8.17 ± 0.41%) and C. japonica var. dissecta (7.90 ± 1.36%). The quaternary alkaloids that had the highest contents in C. chinensis and C. deltoidea were berberine, coptisine, palmatine and epiberberine, whilst in C. japonica and C. japonica var. dissecta they were berberine, coptisine, jatrorrhizine and magnoflorine. Among these samples, those of C. japonica did not contain epiberberine and berberastine whilst those of C. japonica var. dissecta did not contain berberastine. The patterns of their capillary electrophoretograms were found to be very helpful in identifying the origins of the herbs.
Quantitative analysis of alizarin in tissue cultures ofRubiaspecies by high performance liquid chromatography
Authors: Lodhi A. H. , Sant'Ana A. E. G. , Charlwood B. V. 
Published: March 2007

AbstractA rapid, high performance liquid chromatographic (HPLC) method has been developed for the quantitative analysis of alizarin in field grown roots and tissue cultures ofRubia tinctorumandR. peregrina.Alizarin was quantified by HPLC in the presence of trichlorophenol as internal standard using an RP C‐18 Nova‐pak® column eluted isocratically with methanol: 10% aqueous acetic acid (60:40). The minimum detection limit of alizarin was found to be 10.5 ng. The field grown roots and callus ofR. tinctorumcontained, respectively, 939.6 (±17.4) and 335.2 (±4.9) μg/g dry weight total alizarin, whilst similar tissues ofR. peregrinacontained 147.9 (±10.0) and 216.8 (μ0.4) μg/g dry weight total alizarin.
Simultaneous determination of 18 polyketides typical of Aloe by high performance liquid chromatography and photodiode array detection
Authors: Rauwald Hans W. , Sigler Anette 
Published: March 2007

AbstractA high performance liquid chromatographic method has been developed for the simultaneous separation, identification and quantification of secondary products characteristic of Aloe species (Asphodelaceae). The standard compounds comprised eleven anthrone‐C‐glycosyls in diastereomerically pure state, two anthrone aglycones, three anthraquinone aglycones, a tetrahydroanthracene aglycone and a 2‐alkylchromone‐C‐glucosyl. The chromatographic system consisted of a reversed phase silica column (C18, 5 μm) and a combination of linear gradient and isocratic elution with acetonitrile, water and phosphoric acid. Photodiode array detection enabled a specific determination of the compounds even from crude methanolic extracts of plant material from Aloe. The technique described could replace the conventional qualitative thin layer chromatographic systems as a routine method in applied research on Aloe (i.e. for plant physiology, chemotaxonomy, pharmacognosy and pharmaco‐kinetics).
Micellar electrokinetic chromatographic/ultraviolet diode array analysis of Eleutherococcus senticosus
Authors: Pietta P. G. , Mauri P. L. , Gardana C. , Zini L. 
Published: March 2007

AbstractThe main components of the roots of Eleutherococcus senticosus have been separated by capillary electrophoresis in the micellar mode. The best separation was achieved using a fused silica capillary tube and a 25 mM sodium borate buffer (pH 8.25) containing sodium dodecyl sulphate (SDS; 50 mM) at a constant voltage of 280 V/cm. The quantitative determination of eleutheroside B and E in E. senticosus extracts and formulations demonstrates the applicability of this method.
13C nuclear magnetic resonance analysis of two prenyl flavonols from platanus acerifolia buds
Authors: Barron Denis , Aidi Chafei El , Mariotte Anne‐Marie 
Published: March 2007

AbstractThe carbon nuclear magnetic resonance (NMR) data of the acetyl derivatives of 8‐(1,1‐dimethyl‐2‐propen‐1‐y1) galangin and 8‐(1,1‐dimethyl‐2‐propen‐1‐yl) kaempferide, isolated from Platanus acerifolia buds, have been reassigned unambiguously by HETCOR and COLOC experiments on synthetic compounds. The carbon NMR data for the naturally occurring 8‐(1,1‐dimethyl‐2‐propen‐1‐yl) kaempferide is reported for the first time.
Identification and quantification of calystegines, polyhydroxyl nortropane alkaloids
Authors: Dräger Birgit 
Published: March 2007

AbstractCalystegines are a new group of polyhydroxy nortropane alkaloids that have recently been isolated from Calystegia sepium. Thin layer chromatography systems have been developed for preliminary screening for these compounds, whilst quantitative analysis has been achieved, following silylation, by gas chromatography (GC) with an internal standard. The reproducibility and accuracy of the quantification method have been examined. The identity of the calystegines was assessed by co‐chromatography with reference samples, by chemical ionization mass spectroscopy (CI‐MS) of isolated calystegines, and by GC‐MS. Cultured roots of Atropa belladonna were examined for calystegines.