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date, bamboo leaf extract has been reported to exhibit antioxidant, antibacterial, antitumor, anti-inflammatory, antimicrobial, and antiulcerogenic activities [ 2 – 6 ]. Phytochemical research on PES leaves has revealed the functions of 4 flavonoids and

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been officially certified as a natural food additive by the Chinese Ministry of Health [ 3, 4 ]. Flavonoids, phenolic acids, and coumaric lactones are the main bioactive components in BLE, and the flavonoid constituents are diverse and present at high

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. investigated that essential oil and total flavonoids of O. falcata showed antiproliferative activity on SMMC-7721 through down-regulating secretion and expression of MMP-2 in cells [ 6 ]. Yang et al. reported that total flavonoid of O. falcata is a pro

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Dixon, R. A., Xie, D.-Y., Sharma, S. B. (2005) Proanthocyanidins — a final frontier in flavonoid research? New Phytol. 165 , 9–28. Sharma S. B. Proanthocyanidins — a final frontier in

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Acta Veterinaria Hungarica
Authors:
Zita Karancsi
,
Dóra Kovács
,
György Csikó
,
Orsolya Palócz
,
Ákos Jerzsele
,
Péter Gálfi
, and
Orsolya Farkas

juice - inhibition) ( Bailey et al., 1998 ). Several flavonoids, including quercetin, resveratrol and naringenin have also been shown to modulate CYP enzyme activity ( Murray, 2006 ; Wanwimolruk and Prachayasittikul, 2014 ). Flavonoids are the most

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], these major active compounds include flavonoids, coumarins, alkaloids and limonoids [ 2 ]. Citrus peel was the important products of citrus sources and has a long application history in China and other countries due to the high medicinal and

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This study, carried out in 2004–2005, describes the variation of hypericin and flavonoid contents in different samples of Hypericum maculatum . Flowering tops of H. maculatum were collected and analysed for hypericin and flavonoids using HPLC. The contents of hypericin ranged from 0.35–0.95 mg/g; flavonoid contents varied as follows: hyperoside — 16.66–40.89 mg/g, quercitrin — 0.00 to 1.07 mg/g and quercetin — 1.46–4.96 mg/g. The study indicated that flavonoid rutin was absent from the flavonoid pattern of H. maculatum , or present only in trace amounts (0.00–0.67 mg/g), however, H. maculatum is one of the most important sources of hyperoside. The samples of H. maculatum which accumulated high levels of flavonoids seem to be promising for further propagation.

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Fruits are rich sources of flavonoid polyphenolic compounds that seem to be associated with favourable healtheffects. Commonalities and differences are well known in the flavonoid contents of different fruit crops, which suggest alterations in the flavonoid biosynthesis pathway of fruit tissues. This review aims to collect data from molecular genetic studies on the structural and regulatory genes in grape, berries, citrus, pomes and stone fruits to get impression on the state of the art of this field of science. Results indicate that the expression of flavonoid genes is a genotype-dependent and developmentally regulated process. In addition, genetic alterations resulting in specific changes in flavonoid composition are also highlighted. Analysis of colour mutants of grape, bilberry and orange identified the genes responsible for the altered phenotype, and this strategy might offer valuable tools to identify several other candidate genes in different fruits. The application of such data is also discussed in relation with the development of molecular markers.

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Summary

Scutellaria L. is a diverse genus of the Lamiaceae (Labiatae) family of over 300 herbaceous plants commonly known as skullcaps. Various species of Scutellaria are used as ethnobotanical herbs for the treatment of ailments like cancer, jaundice, cirrhosis, anxiety, and nervous disorders. Scutellaria incana L., commonly known as the Hoary skullcap, is a traditional medicinal plant used by native Americans as a sedative for nervousness or anxiety. S. incana metabolites were identified by comparing their high-performance liquid chromatography (HPLC) retention times and mass spectra with those of the corresponding authentic standards. Where standards were unavailable, the structures were characterized on the basis of their tandem mass spectrometry (MS/MS) spectra following collision-induced dissociation (CID) and the accurate masses of the corresponding deprotonated molecules [M-H] (mass accuracy ± 5 ppm). A total of 40 flavonoids, including two phenolic glycosides, were identified from leaves, stems, and roots of S. incana. Differences in the flavonoid composition between leaves, stems, and roots in S. incana were observed although the flavonoid profile of S. incana is consistent with other Scutellaria species. Further work should focus on assessing the potential of S. incana as a source of these bioactive metabolites.

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Summary

A high-performance liquid chromatographic (HPLC) technique coupled with photodiode array (PDA) detection has been proposed for simultaneous determination of five flavonoids, i.e. quercetin 3-O-β-d-glucopyranoside, quercetin 4′-methoxy-3-O-β-d-galactopyranoside, kaempferol 3-O-β-l-rhamnopyranoside, asebotin, and kaempferol 7-methxoy-3-O-α-l-rhamnopyranoside in extract of the whole plant of Saussurea mongolica Franch. The optimum conditions for separation were achieved on a 4.6 × 250 mm i.d., 5-μm particle, C18 column with acetonitrile and 1% acetic acid (20:80, v/v) as the mobile phase at a flow rate of 1.0 mL min−1. For all the analytes, a good linear regression relationship (r of >0.999) was obtained between peak area and concentration over a relatively wide range. The method was validated for repeatability, precision, stability, and accuracy. Seven different extraction procedures were investigated for preparation of the sample solution. The validated method was successfully applied to simultaneous analysis of these flavonoids in S. mongolica and was found to be simple and efficient.

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