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Journal: Phytochemical analysis : PCA

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A livestock poisoning outbreak near Kingman, Arizona, USA, potentially linked to dehydropyrrolizidine alkaloids, prompted an evaluation of some local plants for the presence of these hepatotoxic alkaloids.

Concepts: Plant, Plants, Cryptantha affinis

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Eucalyptus species are widely cultivated in Mediterranean regions. Moreover, plants of this family have been utilized for medicinal purposes. A number of studies have been devoted to the identification of eucalypt phenolics, all of them have focused on specific families of compounds, and no exhaustive profiling has been reported in leaves of this plant.

Concepts: Mass spectrometry, Species, Eucalyptus, Chromatography, High performance liquid chromatography, Electrospray ionization, Fern, Kingdom

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Herbal medicines (HM) and their preparations have been widely used for hundreds of years all over the world. However, they have not been officially recognised due to a lack of adequate or accepted research methodology for their evaluation.

Concepts: Scientific method

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As a Chinese herbal medicine, Jew’s ear has been known for its anti-coagulant effects. Hence it is worthwhile developing an effective technique to extract active components.

Concepts: Chinese herbology, Agaricomycetes, Auricularia auricula-judae

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The structure of polyphenolic compounds influences their anti-oxidant potential. Finding a simple, rapid and reliable analytical method to study the structure-activity relationships for numerous samples is challenging.

Concepts: Atherosclerosis, Oxidative stress, Radical, Vitamin C, Medicago, Medicago truncatula

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INTRODUCTION: Propolis is a chemically complex resinous substance collected by honeybees (Apis mellifera) from tree buds, comprising plant exudates, secreted substances from bee metabolism, pollen and waxes. Its chemical composition depends strongly on the plant sources available around the beehive, which have a direct impact in the quality and bioactivity of the propolis. Being as Portugal is a country of botanical diversity, the phenolic characterisation of propolis from the different regions is a priority. OBJECTIVE: Extensive characterisation of the phenolic composition of Portuguese propolis from different continental regions and islands. METHOD: Forty propolis ethanolic extracts were analysed extensively by liquid chromatography with diode-array detection coupled to electrospray ionisation tandem mass spectrometry (LC-DAD-ESI-MS(n) ). RESULTS: Seventy-six polyphenols were detected in the samples and two groups of propolis were established: the common temperate propolis, which contained the typical poplar phenolic compounds such as flavonoids and their methylated/esterified forms, phenylpropanoid acids and their esters, and an uncommon propolis type with an unusual composition in quercetin and kaempferol glycosides - some of them never described in propolis. CONCLUSION: The method allowed the establishment of the phenolic profile of Portuguese propolis from different geographical locations, and the possibility to use some phenolic compounds, such as kaempferol-dimethylether, as geographical markers. Data suggest that other botanical species in addition to poplar trees can be important sources of resins for Portuguese propolis. Copyright © 2012 John Wiley & Sons, Ltd.

Concepts: Mass spectrometry, Honey bee, Beekeeping, Catechin, Quercetin, Flavonoid, Glycoside, Myricetin

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INTRODUCTION: Echinacea preparations are among the most popular herbal remedies worldwide. Although it is generally assigned immune enhancement activities, the effectiveness of Echinacea is highly dependent on the Echinacea species, part of the plant used, the age of the plant, its location and the method of extraction. OBJECTIVE: The aim of this study was to investigate the capacity of an artificial neural network (ANN) to analyse thin-layer chromatography (TLC) chromatograms as fingerprint patterns for quantitative estimation of three phenylpropanoid markers (chicoric acid, chlorogenic acid and echinacoside) in commercial Echinacea products. MATERIAL AND METHODS: By applying samples with different weight ratios of marker compounds to the system, a database of chromatograms was constructed. One hundred and one signal intensities in each of the TLC chromatograms were correlated to the amounts of applied echinacoside, chlorogenic acid and chicoric acid using an ANN. RESULTS: The developed ANN correlation was used to quantify the amounts of three marker compounds in Echinacea commercial formulations. The minimum quantifiable level of 63, 154 and 98 ng and the limit of detection of 19, 46 and 29 ng were established for echinacoside, chlorogenic acid and chicoric acid respectively. CONCLUSION: A novel method for quality control of herbal products, based on TLC separation, high-resolution digital plate imaging and ANN data analysis has been developed. The method proposed can be adopted for routine evaluation of the phytochemical variability in Echinacea formulations available in the market. Copyright © 2012 John Wiley & Sons, Ltd.

Concepts: Chromatography, Echinacea, Caffeic acid, Herbalism, Cichoric acid, Neural network, Artificial neural network, Herb

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Polygonum capitatum is a well-known Chinese medicinal plant widely used by the Miao people for the treatment of various urologic disorders. Previous investigations have shown the presence of various types of phenolics. Our ultrahigh-performance liquid chromatography with photodiode array detection and mass spectrometry (UPLC-PDA-MS) analysis indicated that flavonoid glycosides and polyphenolic glycosides were its major constituents and quite a number of phenolic compounds have not yet been identified. Identification or characterisation of the major compounds of this plant will contribute to the scientific understanding of the medicinal plant and the authentication of the plant material and its pharmaceutical preparations.

Concepts: Medicine, Mass spectrometry, Catechin, Quercetin, Flavonoid, Resveratrol, Phenols, Tandem mass spectrometry

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INTRODUCTION: The fruits of Vaccinium vitis-idaea L. are a valuable source of biologically active flavonoid derivatives. For studies focused on the purification of its quercetin glycosides (QGs) and related glycosides from plants and for the purpose of biological studies, the availability of numeric datasets from computer-assisted (1) H iterative full spin analysis (HiFSA), that is, (1) H-NMR fingerprinting, can replace and assist the repetitive and tedious two-dimensional NMR identification protocol required for both known and new compounds, respectively. OBJECTIVE: To fully interpret the complex (1) H-NMR fingerprints of eight QGs obtained from the berries of V. vitis-idaea and provide complete and unambiguous signal assignments. METHODS: Vaccinium vitis-idaea QGs were purified in a single run by long-bed gel permeation chromatography and identified by comparison with commercially available compounds using LC-MS combining ion-trap and time-of-flight detection and one- or two-dimensional NMR. The HiFSA analysis yielded full sets of (1) H chemical shifts and proton-proton coupling constants, allowing for field-independent spectral simulation. RESULTS: Signal assignments were achieved for the reference standards and the QGs that dominated in purified fractions. However, even mixtures of two to three QGs could be fitted using the HiFSA approach. In the case of the overlapped sugar resonances, the initial fitting of the (1) H spectra of reference compounds, together with values extracted from the two-dimensional NMR data and literature data, assisted in the process. CONCLUSION: The HiFSA method revealed for the first time the presence of Q-3-O-β-glucopyranoside and Q-3-O-β-glucuronopyranoside in the berries of V. vitis-idaea, and unambiguously confirmed the structures of Q-3-O-[4″-(3-hydroxy-3-methylglutaroyl)]-α-rhamnopyranoside, Q-3-O-α-rhamnopyranoside, Q-3-O-β-galactopyranoside, Q-3-O-α-arabinofuranoside, Q-3-O-β-xylopyranoside and Q-3-O-α-arabinopyranoside. Copyright © 2013 John Wiley & Sons, Ltd.

Concepts: Biology, Chemical compound, John Wiley & Sons, Fruit, Quercetin, Flavonols, Fingerprint, Vaccinium vitis-idaea

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INTRODUCTION: Seeds of Aesculus hippocastanum L. are used in European phytotherapy to treat inflammatory and vascular problems, and also to help in the regulation of the microcirculation. Thus, the quality control of herbal medicines using this species is important. OBJECTIVE: To develop and to optimise a capillary zone electrophoresis method to determine total β-escin in different extracts of A. hippocastanum L. METHODS: The optimal condition found through chemometric approach was: 25 mmol/L of bicarbonate-carbonate buffer, pH 10.3; +20 kV of voltage; 20°C of cartridge temperature; direct ultraviolet detection at 226 nm; 13 mbar injection for 5 s and analysis time within 6 min. RESULTS: Repeatability, coefficient of variation (CV; %) = 3.19, 3.07 and 1.89 (n = 12), and intermediate precision, CV (%) = 3.05, 3.53 and 2.99 (n = 24) for dry, hydroalcoholic and hydroglycolic extracts, respectively were achieved. The accuracy was evaluated through recovery tests in concentration levels of 100, 150 and 200 g/L, ranging from 98.17 to 104.68%. The proposed method exhibited linearity (r = 0.9983) in the concentration range from 101.4 to 907.2 g/L and limits of detection and quantification equal to 11.63 and 38.76 g/L respectively. CONCLUSION: A fast and reliable methodology for determination of total β-escin was successfully validated and applied on extracts of A. hippocastanum L. demonstrating its usefulness to quality control of medicines containing this plant species. Copyright © 2013 John Wiley & Sons, Ltd.

Concepts: Gel electrophoresis, Capillary electrophoresis, Electrophoresis, Micellar electrokinetic chromatography, Affinity electrophoresis, Capillary fringe, Aesculus hippocastanum, Aesculus