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1
Ivey, Kerry L., Jonathan M. Hodgson, Kevin D. Croft, Joshua R. Lewis et Richard L. Prince. « Flavonoid intake and all-cause mortality ». American Journal of Clinical Nutrition 101, no 5 (1 avril 2015) : 1012–20. http://dx.doi.org/10.3945/ajcn.113.073106.
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ABSTRACT Background: Flavonoids are bioactive compounds found in foods such as tea, chocolate, red wine, fruit, and vegetables. Higher intakes of specific flavonoids and flavonoid-rich foods have been linked to reduced mortality from specific vascular diseases and cancers. However, the importance of flavonoids in preventing all-cause mortality remains uncertain. Objective: The objective was to explore the association between flavonoid intake and risk of 5-y mortality from all causes by using 2 comprehensive food composition databases to assess flavonoid intake. Design: The study population included 1063 randomly selected women aged >75 y. All-cause, cancer, and cardiovascular mortalities were assessed over 5 y of follow-up through the Western Australia Data Linkage System. Two estimates of flavonoid intake (total flavonoidUSDA and total flavonoidPE) were determined by using food composition data from the USDA and the Phenol-Explorer (PE) databases, respectively. Results: During the 5-y follow-up period, 129 (12%) deaths were documented. Participants with high total flavonoid intake were at lower risk [multivariate-adjusted HR (95% CI)] of 5-y all-cause mortality than those with low total flavonoid consumption [total flavonoidUSDA: 0.37 (0.22, 0.58); total flavonoidPE: 0.36 (0.22, 0.60)]. Similar beneficial relations were observed for both cardiovascular disease mortality [total flavonoidUSDA: 0.34 (0.17, 0.69); flavonoidPE: 0.32 (0.16, 0.61)] and cancer mortality [total flavonoidUSDA: 0.25 (0.10, 0.62); flavonoidPE: 0.26 (0.11, 0.62)]. Conclusions: Using the most comprehensive flavonoid databases, we provide evidence that high consumption of flavonoids is associated with reduced risk of mortality in older women. The benefits of flavonoids may extend to the etiology of cancer and cardiovascular disease.
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Wollenweber, Eckhard, Marion Dörr et Matthias Christ. « Flavonoid Aglycones from the Leaf and Stem Exudates of Some Geraniaceae Species ». Natural Product Communications 6, no 1 (janvier 2011) : 1934578X1100600. http://dx.doi.org/10.1177/1934578x1100600105.
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Six species of Pelargonium and one species of Geranium were studied for their surface flavonoids. Some of them were found to exhibit an unexpectedly high number of methylated flavonoids, mostly flavonols. The chemotaxonomic significance of exudate flavonoid diversification is shortly addressed.
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Nikolova, M., et S. Ivancheva. « Distribution of Surface Flavonoids in Bulgarian Plants ». Natural Product Communications 1, no 11 (novembre 2006) : 1934578X0600101. http://dx.doi.org/10.1177/1934578x0600101119.
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The review describes the distribution of surface flavonoids in Bulgarian plants. More than 100 species of Asteraceae, Lamiaceae, Scrophulariaceae, Geraniaceae and other families have been checked for external flavonoid aglycones. The flavonoid profiles of Asteraceae species are composed of a wide array of flavones and flavonols, mainly based upon 6-substituted derivatives. Flavone aglycones are predominant in the exudates of Lamiaceae species. Apigenin, luteolin and their derivatives were most commonly found in the studied species of Scropulariaceae and Lamiaceae. It has been shown that species of Geraniaceae, Ranunculaceae, and Solanaceae contain flavonoids of the flavonol class as surface constituents. Surface distributed flavonoids appear to have been well studied and useful for chemotaxonomy. If there is not too much infraspecific variation, flavonoid profiles can be used as taxonomic characters to distinguish species. Correlations between external flavonoid formation and local environment are apparent.
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Li, Chengshuai, Lijing Zhang, Decao Niu, Shuzhen Nan, Xiumei Miao, Xiaowei Hu et Hua Fu. « Investigation of flavonoid expression and metabolite content patterns during seed formation of Artemisia sphaerocephala Krasch. » Seed Science Research 31, no 2 (juin 2021) : 136–48. http://dx.doi.org/10.1017/s096025852100012x.
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AbstractFlavonoids are a group of phenolic secondary metabolites in plants that have important physiological, ecological and economic value. In this study, using the desert plant Artemisia sphaerocephala Krasch. as the sample material, the content and components of the total flavonoids in its seeds at seven different developmental stages were determined. In addition, the genes involved in flavonoid metabolism were identified by full-length transcriptome sequencing (third-generation sequencing technology based on PacBio RS II). Their expression levels were analysed by RNA-seq short reading sequencing, to reveal the patterns and regulation mechanisms of flavonoid accumulation during seed development. The key results were as follows: the content of total flavonoids in mature seeds was 15.05 mg g−1, including five subclasses: flavonols, chalcones, flavones, flavanones and proanthocyanidins, among which flavonols accounted for 45.78%. The period of rapid accumulation of flavonoids was 40–70 d following anthesis. The high expression of phenylalanine ammonia-lyase (PAL), 4-coumarate-CoA ligase (4CL) and UDP-glucose:flavonoids 3-o-glucosyltransferase (UF3GT) promoted the accumulation of total flavonoids, while the high expression of flavonoids 3′-hydroxylase (F3′H) and flavonols synthase (FLS) made flavanols the main component. Transcription factors such as the MYB-bHLH-WDR (MBW) complex and Selenium-binding protein (SBP) directly regulated the structural genes of flavonoid metabolism, while C2H2-type zinc finger (C2H2), Zinc-finger transcription factor (GATA), Dehydration-responsive element binding (DREB), Global Transcription factor Group E protein (GTE), Trihelix DNA-binding factors (Trihelix) and Phytochrome-interacting factor (PIF) indirectly promoted the synthesis of flavonoids through hormones such as brassinoidsteroids (BRs) and abscisic acid (ABA). These results provided valuable resources for the application of related genes in genetics and breeding.
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Iwashina, Tsukasa. « FLAVONOIDS IN THE SPECIES OF THE FAMILY ARACEAE : A REVIEW ». Buletin Kebun Raya 23, no 1 (30 avril 2020) : 1–24. http://dx.doi.org/10.14203/bkr.v23i1.1.
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Flavonoids is one of the secondary metabolites and consists of two phenyl rings (A- and B-rings) connected by a three carbon bridge. Over 8000 kinds of flavonoids were reported from vascular plants and Bryophytes. This paper reviewed the flavonoid characters of the Araceae s.l. (including the Lemnaceae). Major flavonoids of the family were C-glycosylflavones with the exception for subfamilies Gymnostachydoideae and Orontioideae. Other flavonoid classes, i.e. anthocyanins, flavones, flavonols, flavan and proanthocyanidins, were reported in all subfamilies. Flavanone and C-glycosylflavanone were isolated from Spirodela polyrhiza and Anthurium binotii, respectively. However, dihydroflavonol, chalcone, dihydrochalcone, aurone, and isoflavonoids were not reported in the Araceae. Although Araceae s.l. is a large family consisting of ca. 3645 species and ca. 144 genera, flavonoids were surveyed only in 146 species of 48 genera, as far as known.
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Kim, Bo-Ram, Ah-Reum Han et Ik-Soo Lee. « Microbial Transformation of Flavonoids in Cultures of Mucor hiemalis ». Natural Product Communications 15, no 12 (décembre 2020) : 1934578X2097774. http://dx.doi.org/10.1177/1934578x20977743.
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Flavonoids are plant secondary metabolites that are well known for their health-promoting properties as nutraceuticals in diets. Bioavailability and biological activities of flavonoids vary among the individual subclasses with different patterns of substitution, inclusive of glycosylation, to their basic structures. Many flavonoids exist as glycosides in plants. This study investigated the possibility of glycosylation of flavonoids through biotransformation using filamentous fungi as whole-cell biocatalysts. Microbial transformations of ten flavonoids (four flavones, four flavonols, a flavanone, and an aurone) were performed in cultures of Mucor hiemalis KCTC 26779. As a result, a flavonoid glycoside was obtained which has not been described previously. The chemical structure of this product was elucidated as 6,2′-dimethoxyflavonol-3- O-β-d-glucopyranoside by analyzing 1-dimensional and 2-dimensional-nuclear magnetic resonance spectral and high-resolution electrospray ionization mass spectral data. This compound could be useful for further biological and bioavailability studies, as well as expanding the library of flavonoid derivatives.
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Rasmussen et Breinholt. « Non-Nutritive Bioactive Food Constituents of Plants : Bioavailability of Flavonoids ». International Journal for Vitamin and Nutrition Research 73, no 2 (1 mars 2003) : 101–11. http://dx.doi.org/10.1024/0300-9831.73.2.101.
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Flavonoids are polyphenols widely distributed in the plant kingdom, and are present in fruits andvegetables regularly consumed by humans. In vitro metabolic studies of flavonoids in rat liver microsomes identified the 3’, 4’-dihydroxylated derivatives as the major metabolic endpoint. However, in vivo in rats almost none of this metabolite and only minor amounts of the 4’-monohydroxylated derivative was produced. Flavonoids with the 4’-monohydroxylated structure were generally not metabolised and were excreted unchanged in urine in higher amounts than other flavonoids investigated. It has for long been a controversy, whether flavonoids are absorbed as the intact glycoside or whether they have to be hydrolysed to the free aglycon prior to absorption. Recent data suggest that b-glucosidases and maybe also lactase phlorizin hydrolase (LPH) in the small intestine are capable of hydrolysing flavonoid glucosides and these compounds are thus taken up as the free aglycon and not as the intact glycosides. LC-MS analyses of 12 dietary flavonoids in human urine showed that no flavonoid glycosides were excreted, and that the citrus flavanones and phloretin are excreted in higher amounts than the flavonols. Furthermore, total flavonoid excretion may be a useful biomarker for habitual fruit and vegetable consumption.
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Wang, Lanxiang, Pui Ying Lam, Andy C. W. Lui, Fu-Yuan Zhu, Mo-Xian Chen, Hongjia Liu, Jianhua Zhang et Clive Lo. « Flavonoids are indispensable for complete male fertility in rice ». Journal of Experimental Botany 71, no 16 (9 mai 2020) : 4715–28. http://dx.doi.org/10.1093/jxb/eraa204.
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Abstract Flavonoids are essential for male fertility in some but not all plant species. In rice (Oryza sativa), the chalcone synthase mutant oschs1 produces flavonoid-depleted pollen and is male sterile. The mutant pollen grains are viable with normal structure, but they display reduced germination rate and pollen-tube length. Analysis of oschs1/+ heterozygous lines shows that pollen flavonoid deposition is a paternal effect and fertility is independent of the haploid genotypes (OsCHS1 or oschs1). To understand which classes of flavonoids are involved in male fertility, we conducted detailed analysis of rice mutants for branch-point enzymes of the downstream flavonoid pathways, including flavanone 3-hydroxylase (OsF3H; flavonol pathway entry enzyme), flavone synthase II (CYP93G1; flavone pathway entry enzyme), and flavanone 2-hydroxylase (CYP93G2; flavone C-glycoside pathway entry enzyme). Rice osf3h and cyp93g1 cyp93g2 CRISPR/Cas9 mutants, and cyp93g1 and cyp93g2 T-DNA insertion mutants showed altered flavonoid profiles in anthers, but only the osf3h and cyp93g1 cyp93g2 mutants displayed reduction in seed yield. Our findings indicate that flavonoids are essential for complete male fertility in rice and a combination of different classes (flavanones, flavonols, flavones, and flavone C-glycosides) appears to be important, as opposed to the essential role played primarily by flavonols that has been previously reported in several plant species.
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Wollenweber, Eckhard, et Marion Dörr. « Exudate Flavonoids of Some Juglandaceae ». Natural Product Communications 4, no 2 (février 2009) : 1934578X0900400. http://dx.doi.org/10.1177/1934578x0900400208.
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Six species of Juglandaceae have been checked for the occurrence of flavonoid aglycones on their leaf and fruit surfaces. Except for one, they exhibit flavonols, mostly methyl ethers of kaempferol and quercetin, including 6- O-substituted derivatives. Apigenin and acacetin are the only flavones found so far. Flavonoids accumulated on leaves are different from those excreted on green fruits. It has become evident that in future studies greater attention must be paid to the localization of flavonoid aglycones in different plant organs.
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Karapandzova, Marija, Gjose Stefkov, Ivana Cvetkovikj, Jasmina Petreska Stanoeva, Marina Stefova et Svetlana Kulevanova. « Flavonoids and Other Phenolic Compounds in Needles of Pinus peuce and Other Pine Species from the Macedonian Flora ». Natural Product Communications 10, no 6 (juin 2015) : 1934578X1501000. http://dx.doi.org/10.1177/1934578x1501000647.
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Flavonoids and other phenolic compounds in young needles of four pine species, Pinus peuce, P. nigra, P. mugo and P. sylvestris from the Macedonian flora were investigated. The amount of total phenols and total flavonoids were determined using Folin-Ciocalteau and aluminum chloride assay, respectively. The obtained results revealed that the total phenolic content (TPC) and total flavonoids content (TFC) varied among different pine species ranging from 9.8 to 14.0 mg GAE/g and from 3.3 to 7.2 mg CE/g of dried plant material, respectively. Qualitative analysis of flavonoids and other phenolic components was made by a LC-DAD/ESI-MSn optimized chromatographic method. A total of 17 phenolic components were identified and classified as: acids (2), procyanidins (2) and flavonoid glycosides (13). The most prevalent components were flavonoid glycosides, especially flavonols and methylated flavonols (9). Additionally, 3 components were found as acylated flavonol glycosides with ferulic and p-coumaric acid. The last one was found not only in esterified form but also in the free form. Only one flavone-apigenin glycoside was detected. Procyanidins were identified as catechin derivatives, both dimers and trimers.
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Wollenweber, Eckhard, Matthias Christ, R. Hugh Dunstan, James N. Roitman et Jan F. Stevens. « Exudate Flavonoids in Some Gnaphalieae and Inuleae (Asteraceae) ». Zeitschrift für Naturforschung C 60, no 9-10 (1 octobre 2005) : 671–78. http://dx.doi.org/10.1515/znc-2005-9-1003.
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Abstract Three members of the tribe Gnaphalieae and six members of the tribe Inuleae (Asteraceae) were analyzed for their exudate flavonoids. Whereas some species exhibit rather trivial flavonoids, others produce rare compounds. Spectral data of rare flavonoids are reported and their structural identification is discussed. 6-Oxygenation of flavonols is a common feature of two Inula species and Pulicaria sicula. By contrast, flavonoids with 8-oxygenation, but lacking 6-oxygenation, are common in two out of three Gnaphalieae species examined. In addition, B-ring deoxyflavonoids are abundantly present in the leaf exudates of Helichrysum italicum (Gnaphalieae). These distinctive features of the two Asteraceae tribes are in agreement with previous flavonoid surveys of these and related taxa.
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Wollenweber, Eckhard, Marion Dörr et James N. Roitman. « Epicuticular Flavonoids of Some Scrophulariaceae ». Zeitschrift für Naturforschung C 55, no 1-2 (1 février 2000) : 5–9. http://dx.doi.org/10.1515/znc-2000-1-203.
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Abstract Twenty-two species of Scophulariaceae have been found to accumulate flavonoid aglycones externally on their leaves and stems. They belong to the genera Anarrhinum , Antirrhinum , Asarina, Calceolaria, Mimulus, and Odontites. Most of the flavonoids are methylated flavones and flavonols, some with 6-O and/or 8-O -substitution. One of them is the natural isobutyryl ester of a rare flavone.
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Fardoun, Manal Muin, Dina Maaliki, Nabil Halabi, Rabah Iratni, Alessandra Bitto, Elias Baydoun et Ali H. Eid. « Flavonoids in adipose tissue inflammation and atherosclerosis : one arrow, two targets ». Clinical Science 134, no 12 (juin 2020) : 1403–32. http://dx.doi.org/10.1042/cs20200356.
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Abstract Flavonoids are polyphenolic compounds naturally occurring in fruits and vegetables, in addition to beverages such as tea and coffee. Flavonoids are emerging as potent therapeutic agents for cardiovascular as well as metabolic diseases. Several studies corroborated an inverse relationship between flavonoid consumption and cardiovascular disease (CVD) or adipose tissue inflammation (ATI). Flavonoids exert their anti-atherogenic effects by increasing nitric oxide (NO), reducing reactive oxygen species (ROS), and decreasing pro-inflammatory cytokines. In addition, flavonoids alleviate ATI by decreasing triglyceride and cholesterol levels, as well as by attenuating inflammatory mediators. Furthermore, flavonoids inhibit synthesis of fatty acids and promote their oxidation. In this review, we discuss the effect of the main classes of flavonoids, namely flavones, flavonols, flavanols, flavanones, anthocyanins, and isoflavones, on atherosclerosis and ATI. In addition, we dissect the underlying molecular and cellular mechanisms of action for these flavonoids. We conclude by supporting the potential benefit for flavonoids in the management or treatment of CVD; yet, we call for more robust clinical studies for safety and pharmacokinetic values.
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Johnson, Emanuel L., et Walter F. Schmidt. « Flavonoids as Chemotaxonomic Markers for Erythroxylum ulei ». Zeitschrift für Naturforschung C 54, no 11 (1 novembre 1999) : 881–88. http://dx.doi.org/10.1515/znc-1999-1105.
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Abstract Leaf extracts of Erythroxylum ulei O. E. Schulz, produced six O-conjugated flavonoids. Three of the flavonoid aglycones were isoflavones, two were isoflavanones and the remainder a flavonol (quercetin). The major glycosides of these flavonols included mono-and dirham-nosides, mono-glucosides and galactosides with either 3̕ 4̕, or 7 linkage or a combination thereof. The two isoflavanones, in addition to being glycosylated, possessed a methyl group at position 2 of the C-ring. These flavonoids may be used as chemotaxonomic markers for the taxon.
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Choi, Roy C. Y., Judy T. T. Zhu, Amanda W. Y. Yung, Pinky S. C. Lee, Sherry L. Xu, Ava J. Y. Guo, Kevin Y. Zhu, Tina T. X. Dong et Karl W. K. Tsim. « Synergistic Action of Flavonoids, Baicalein, and Daidzein in Estrogenic and Neuroprotective Effects : A Development of Potential Health Products and Therapeutic Drugs against Alzheimer’s Disease ». Evidence-Based Complementary and Alternative Medicine 2013 (2013) : 1–10. http://dx.doi.org/10.1155/2013/635694.
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Despite the classical hormonal effect, estrogen has been reported to mediate neuroprotection in the brain, which leads to the searching of estrogen-like substances for treating neurodegenerative diseases. Flavonoids, a group of natural compounds, are well known to possess estrogenic effects and used to substitute estrogen, that is, phytoestrogen. Flavonoid serves as one of the potential targets for the development of natural supplements and therapeutic drugs against different diseases. The neuroprotection activity of flavonoids was chosen for a possible development of anti-Alzheimer's drugs or food supplements. The estrogenic activity of two flavonoids, baicalein and daidzein, were demonstrated by their strong abilities in stimulating estrogen receptor phosphorylation and transcriptional activation of estrogen responsive element in MCF-7 breast cells. The neuroprotection effects of flavonoids againstβ-amyloid (Aβ) were revealed by their inhibition effects onin vitroAβaggregation and Aβ-induced cytotoxicity in PC12 neuronal cells. More importantly, the estrogenic and neuroprotective activities of individual flavonoid could be further enhanced by the cotreatment in the cultures. Taken together, this synergistic effect of baicalein and daidzein might serve as a method to improve the therapeutic efficacy of different flavonoids against Aβ, which might be crucial in developing those flavonoidsin treating Alzheimer's disease in the future.
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Wollenweber, Eckhard, Ralf Fischer, Marion Dörr, Kathryn Irvine, Cliff Pereira et Jan F. Stevens. « Chemodiversity of Exudate Flavonoids in Cassinia and Ozothamnus (Asteraceae, Gnaphalieae) ». Zeitschrift für Naturforschung C 63, no 9-10 (1 octobre 2008) : 731–39. http://dx.doi.org/10.1515/znc-2008-9-1019.
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The lipophilic exudates deposited on aerial parts of four species of Cassinia and twelve species of Ozothamnus (Asteraceae, Gnaphalieae) have been analyzed for the presence of flavonoid aglycones and some other phenolics. A total of 55 flavonoids were identified, including several rare flavonols. Flavonols are prevailing over flavones, and 8-O-substitution is dominant in both groups. Ozothamnus rosmarinifolius is exceptional in producing several coumarins. Four dihydrobenzofurans have also been identified from this species. Cluster analysis and principal coordinate analysis of the flavonoid data provide support for combining species of Cassinia and Ozothamnus into a single genus.
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Cheon, Minjung, Minsung Chung et Yongsoon Park. « Association between Dietary Intake of Flavonoids and Cancer Recurrence among Breast Cancer Survivors ». Nutrients 13, no 9 (30 août 2021) : 3049. http://dx.doi.org/10.3390/nu13093049.
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Intake of flavonoids is associated with the incidence of breast cancer, but the association between the intake of flavonoids and cancer recurrence is unclear. This study aimed to investigate the hypothesis that intake of flavonoids and flavonoid-rich foods is negatively associated with cancer recurrence. Among 572 women who underwent breast cancer surgery, 66 patients had a cancer recurrence. Dietary data were collected using a structured 24-h dietary recall, and intake of flavonoids was calculated based on the Korea Rural Development Administration flavonoid database. Among overweight and obese patients, disease-free survival was associated with intake of flavonoids (p = 0.004) and flavonoid-rich foods (p = 0.003). Intake of flavonoids (hazard ratio (HR) = 0.249, 95% confidence interval (CI): 0.09–0.64) and flavonoid-rich foods (HR = 0.244, 95% CI: 0.09–0.66) was negatively associated with cancer recurrence after adjusting for confounding factors in overweight and obese patients. Consumption of flavonoids and flavonoid-rich foods was lower in overweight and obese patients with cancer recurrence than those without recurrence and in normal-weight patients. This study suggests that intake of flavonoids and flavonoid-rich foods could have beneficial effects on cancer recurrence in overweight and obese breast cancer survivors.
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Beking, Kristopher, et Amandio Vieira. « Flavonoid intake and disability-adjusted life years due to Alzheimer’s and related dementias : a population-based study involving twenty-three developed countries ». Public Health Nutrition 13, no 9 (11 janvier 2010) : 1403–9. http://dx.doi.org/10.1017/s1368980009992990.
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AbstractObjectiveDietary flavonoids and their metabolites may have neuroprotective effects against age-associated neurodegenerative disorders such as Alzheimer’s and related dementias (dementia). There is a lack of population studies, however, on correlations between flavonoid intake and dementia. The main objective of the present study was to analyse such a relationship at a large-scale population level.DesignBased on global data (FAO, WHO), databases were generated for: (i) flavonoid content of foods; (ii) per capita national dietary intakes of flavonoids and other dietary factors; and (iii) disability-adjusted life years – a measure of burden and death – due to dementia. Five major flavonoid subclasses were examined. To minimize influences due to accuracy and reliability of the disease source data, twenty-three developed countries were selected after statistical evaluation.ResultsFlavonols and combined flavonoids (all five combined) intakes were the only two parameters with significant (P < 0·05) negative dementia correlations. Multiple linear regression models confirmed this relationship, and excluded confounding from some other dietary and non-dietary factors. Similar analyses with non-dementia, neurological/psychiatric diseases did not yield significant correlations.ConclusionsAt a global level, and in the context of different genetic backgrounds, our results suggest that higher consumption of dietary flavonoids, especially flavonols, is associated with lower population rates of dementia in these countries.
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Srivastava, Neeharika, Aishwarya Singh Chauhan et Bechan Sharma. « Isolation and Characterization of Some Phytochemicals from Indian Traditional Plants ». Biotechnology Research International 2012 (11 décembre 2012) : 1–8. http://dx.doi.org/10.1155/2012/549850.
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The present study was designed to evaluate relative contribution of different polyphenols (total phenolics, flavonoids, flavonols) and their antioxidants activities in aqueous extracts of different parts of some plants; Argemone mexicana, Datura metel, Calotropis procera, Thevetia peruviana, and Cannabis sativa. The antioxidants (total phenolics, flavonoids, flavones) were determined by chemical methods. The antioxidant capacities of these extracts were evaluated by FRAP assay. The results demonstrated that phenolic content was maximally present in leaves of T. peruviana. This plant exhibited minimum phenolic content in its flower as compared to other plants. The flower of D. metel contained maximum phenolic content. The flavonoids were present in highest quantity in leaves of C. procera while T. peruviana flowers showed maximum flavonoid content. The fruits of C. sativa contained maximum quantity of flavonoid as compared to other plants tested. The flower extract of C. sativa possessed highest FRAP value followed by A. mexicana and fruit of C. procera. The values of ratios of different polyphenolic compounds present in plant extracts indicated that flower of D. metel contained maximum total flavonoids and minimum phenolics. These results suggested that levels of total phenolics, flavonoids and their FRAP indices exhibited specificity to different plants and their parts.
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Nurlinda, Nurlinda, Virsa Handayani et Faradiba Abdul Rasyid. « Spectrophotometric Determination of Total Flavonoid Content in Biancaea Sappan (Caesalpinia sappan L.) Leaves ». Jurnal Fitofarmaka Indonesia 8, no 3 (4 mars 2021) : 1–4. http://dx.doi.org/10.33096/jffi.v8i3.712.
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AbstractBiancaea sappan (BS) is traditionally used to treat anticonvulsants, anti-inflammatory, antiproliferative, anticoagulant, antiviral, immunostimulant, antioxidant, and antimicrobial treatments. Flavonoids are found in Secang; flavonoids are secondary metabolites that have antioxidant activity. This study aims to identify the flavonoids using TLC and determination of flavonoids content in BS leaves. Initially, The methanol extract of BS was obtained by maceration with ethanol. The qualitative analysis of flavonoid was using TLC and visualization by sprayed with AlCl3. The determination of total flavonoid content is conducted based on the AlCl3 method with total flavonoids expressed in QE (Quercetin equivalent) at the maximum wavelength of 431 nm. The research results showed that BS leaves contain flavonoids and the total flavonoid content of BS leaf extract is 1.0318 mg QE / g extract.Keywords: Caesalpinia sappan; Flavonoid content, Spectrophotometric
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Jun, Shinyoung, Sangah Shin et Hyojee Joung. « Estimation of dietary flavonoid intake and major food sources of Korean adults ». British Journal of Nutrition 115, no 3 (23 octobre 2015) : 480–89. http://dx.doi.org/10.1017/s0007114515004006.
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AbstractEpidemiological studies have suggested that flavonoids exhibit preventive effects on degenerative diseases. However, lack of sufficient data on flavonoid intake has limited evaluating the proposed effects in populations. Therefore, we aimed to estimate the total and individual flavonoid intakes among Korean adults and determine the major dietary sources of these flavonoids. We constructed a flavonoid database of common Korean foods, based on the food list reported in the 24-h recall of the Korea National Health and Nutrition Examination Survey (KNHANES) 2007–2012, using data from the Korea Functional Food Composition Table, US Department of Agriculture flavonoid database, Phenol-Explorer database and other analytical studies. This database, which covers 49 % of food items and 76 % of food intake, was linked with the 24-h recall data of 33 581 subjects aged ≥19 years in the KNHANES 2007–2012. The mean daily intake of total flavonoids in Korean adults was 318·0 mg/d, from proanthocyanidins (22·3 %), flavonols (20·3 %), isoflavones (18·1 %), flavan-3-ols (16·2 %), anthocyanidins (11·6 %), flavanones (11·3 %) and flavones (0·3 %). The major contributing food groups to the flavonoid intake were fruits (54·4 %), vegetables (20·5 %), legumes and legume products (16·2 %) and beverages and alcohols (3·1 %), and the major contributing food items were apples (21·9 %), mandarins (12·5 %), tofu (11·5 %), onions (9·6 %) and grapes (9·0 %). In the regression analysis, the consumption of legumes and legume products, vegetables and fruits predicted total flavonoid intake the most. The findings of this study could facilitate further investigation on the health benefits of flavonoids and provide the basic information for establishing recommended flavonoid intakes for Koreans.
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Shen, Ting, Fengting Hu, Qianrui Liu, Haiyan Wang et Houhua Li. « Analysis of Flavonoid Metabolites in Chaenomeles Petals Using UPLC-ESI-MS/MS ». Molecules 25, no 17 (2 septembre 2020) : 3994. http://dx.doi.org/10.3390/molecules25173994.
Texte intégralRésumé :
Chaenomeles species are used for both ornamental decoration and medicinal purposes. In order to have a better understanding of the flavonoid profile of Chaenomeles, the petals of four Chaenomeles species, including Chaenomeles japonica (RB), Chaenomeles speciose (ZP), Chaenomeles sinensis (GP), and Chaenomeles cathayensis (MY), were selected as experimental material. The total flavonoid content of GP was found to be the highest, followed by MY, ZP, and RB. In total, 179 flavonoid metabolites (including 49 flavonols, 46 flavonoids, 19 flavone C-glycosides, 17 procyanidins, 15 anthocyanins, 10 flavanols, 10 dihydroflavonoids, 6 isoflavones, 5 dihydroflavonols, and 2 chalcones) were identified by Ultra-Performance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry. Screening of differential flavonoid metabolites showed that GP had higher levels of metabolites when compared with the other three Chaenomeles species. Annotation and enrichment analysis of flavonoid metabolites revealed that cyanidin 3,5-diglucoside and pelargonidin-3,5-diglucoside anthocyanins are likely responsible for the color differences of the four Chaenomeles petals. Additionally, a large number of flavonoids, flavonols, and isoflavones were enriched in the petals of GP. This study provides new insights into the development and utilization of Chaenomeles petals and provides a basis for future investigations into their utilization.
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Chen, Qianru, Xianxian Wang, Xiaolong Yuan, John Shi, Chengsheng Zhang, Ning Yan et Changliang Jing. « Comparison of Phenolic and Flavonoid Compound Profiles and Antioxidant and α-Glucosidase Inhibition Properties of Cultivated Soybean (Glycine max) and Wild Soybean (Glycine soja) ». Plants 10, no 4 (20 avril 2021) : 813. http://dx.doi.org/10.3390/plants10040813.
Texte intégralRésumé :
Wild soybean (Glycine soja Sieb.et Zucc; WS) has been used as a traditional food in China for many years and contains significantly higher levels of isoflavones than cultivated soybean (Glycine max; CS), but the secondary metabolites, including flavonoids and the phenolic composition differences between them, remain unclear. The results showed that WS possessed significantly higher total phenolic and flavonoid content and exhibited better antioxidant and α-glucosidase inhibition activities as well as excellent protective effects against H2O2-induced oxidative injury in a human endothelial cell line. Through metabolomic analysis, 642 metabolites were identified, and 238 showed differential expression, with 151 upregulated and 87 downregulated. A total of 79 flavonoid compounds were identified, 42 of which were upregulated in WS. 2′-Hydroxygenistein, garbanzol, protocatechuic aldehyde, ligustilide, and resveratrol were the most discriminated compounds in WS. The metabolic pathway analysis of differential metabolites related to the biosynthesis of flavonoids and phenolic acids were the biosynthesis of phenylpropanoids, flavonoids, isoflavonoids, flavones, and flavonols. This study substantially elucidated differences in the content of flavonoids and biological activities between WS and CS, which is useful information for the effective utilization of these two black soybean species in food processing.
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Shui, Lanya, Kaisen Huo, Yan Chen, Zilin Zhang, Yanfang Li et Jun Niu. « Integrated metabolome and transcriptome revealed the flavonoid biosynthetic pathway in developing Vernonia amygdalina leaves ». PeerJ 9 (26 avril 2021) : e11239. http://dx.doi.org/10.7717/peerj.11239.
Texte intégralRésumé :
Background Vernonia amygdalina as a tropical horticultural crop has been widely used for medicinal herb, feed, and vegetable. Recently, increasing studies revealed that this species possesses multiple pharmacological properties. Notably, V. amygdalina leaves possess an abundance of flavonoids, but the specific profiles of flavonoids and the mechanisms of fl avonoid bi osynthesis in developing leaves are largely unknown. Methods The total flavonoids of V. amygdalina leaves were detected using ultraviolet spectrophotometer. The temporal flavonoid profiles of V. amygdalina leaves were analyzed by LC-MS. The transcriptome analysis of V. amygdalina leaves was performed by Illumina sequencing. Functional annotation and differential expression analysis of V. amygdalina genes were performed by Blast2GO v2.3.5 and RSEM v1.2.31, respectively. qRT-PCR analysis was used to verify the gene expressions in developing V. amygdalina leaves. Results By LC-MS analysis, three substrates (p-coumaric acid, trans-cinnamic acid, and phenylalanine) for flavonoid biosynthesis were identified in V. amygdalina leaves. Additionally, 42 flavonoids were identified from V. amygdalina leaves, including six dihydroflavones, 14 flavones, eight isoflavones, nine flavonols, two xanthones, one chalcone, one cyanidin, and one dihydroflavonol. Glycosylation and methylation were common at the hydroxy group of C3, C7, and C4’ positions. Moreover, dynamic patterns of different flavonoids showed diversity. By Illumina sequencing, the obtained over 200 million valid reads were assembled into 60,422 genes. Blast analysis indicated that 31,872 genes were annotated at least in one of public databases. Greatly increasing molecular resources makes up for the lack of gene information in V. amygdalina. By digital expression profiling and qRT-PCR, we specifically characterized some key enzymes, such as Va-PAL1, Va-PAL4, Va-C4H1, Va-4CL3, Va-ACC1, Va-CHS1, Va-CHI, Va-FNSII, and Va-IFS3, involved in flavonoid biosynthesis. Importantly, integrated metabolome and transcriptome data of V. amygdalina leaves, we systematically constructed a flavonoid biosynthetic pathway with regards to material supplying, flavonoid scaffold biosynthesis, and flavonoid modifications. Our findings contribute significantly to understand the underlying mechanisms of flavonoid biosynthesis in V. amygdalina leaves, and also provide valuable information for potential metabolic engineering.
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Bonvehí, Josep Serra, et Francesc Ventura Coll. « Phenolic Composition of Propolis from China and from South America ». Zeitschrift für Naturforschung C 49, no 11-12 (1 décembre 1994) : 712–18. http://dx.doi.org/10.1515/znc-1994-11-1204.
Texte intégralRésumé :
Flavonoids and other phenolic compounds were determined in 15 samples of propolis originating from China, from Brazil, and from Uruguay. A total of 24 compounds were identified using mainly HPLC and a few other analytical methods. The most abundant compounds found were benzoic acid and benzaldehyde derivatives, flavones, flavonols. and flavanones. 80% of the samples contained at least 22 g/100 g of flavonoids, primarily acacetin, isorhamnetin, apigenin, and pinocembrin. The flavonoid patterns were sufficiently distinctive to permit discrimination between propolis from China, from Uruguay, and from Brazil.
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Selvakumar, Priyanga, Aja Badgeley, Paige Murphy, Hina Anwar, Urvashi Sharma, Katharine Lawrence et Ashakumary Lakshmikuttyamma. « Flavonoids and Other Polyphenols Act as Epigenetic Modifiers in Breast Cancer ». Nutrients 12, no 3 (13 mars 2020) : 761. http://dx.doi.org/10.3390/nu12030761.
Texte intégralRésumé :
Breast cancer is a common cancer that occurs due to different epigenetic alterations and genetic mutations. Various epidemiological studies have demonstrated an inverse correlation between breast cancer incidence and flavonoid intake. The anti-cancer action of flavonoids, a class of polyphenolic compounds that are present in plants, as secondary metabolites has been a major topic of research for many years. Our review analysis demonstrates that flavonoids exhibit anti-cancer activity against breast cancer occurring in different ethnic populations. Breast cancer subtype and menopausal status are the key factors in inducing the flavonoid’s anti-cancer action in breast cancer. The dose is another key factor, with research showing that approximately 10 mg/day of isoflavones is required to inhibit breast cancer occurrence. In addition, flavonoids also influence the epigenetic machinery in breast cancer, with research demonstrating that epigallocatechin, genistein, and resveratrol all inhibited DNA methyltransferase and altered chromatin modification in breast cancer. These flavonoids can induce the expression of different tumor suppressor genes that may contribute to decreasing breast cancer progression and metastasis. Additional studies are required to confirm the contribution of epigenetic modifications by flavonoids to breast cancer prevention.
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WEBB, Michael R., et Susan E. EBELER. « Comparative analysis of topoisomerase IB inhibition and DNA intercalation by flavonoids and similar compounds : structural determinates of activity ». Biochemical Journal 384, no 3 (7 décembre 2004) : 527–41. http://dx.doi.org/10.1042/bj20040474.
Texte intégralRésumé :
Flavonoids and other polyphenolic compounds have been shown to inhibit human topoisomerase IB (topo I) through both inhibition of relaxation activity and through stabilization of the cleavable complex (poisoning). Some flavonoids have also been shown to intercalate DNA, and an association of topoisomerase inhibition with intercalation has been noted. We surveyed 34 polyphenolic compounds, primarily flavonoid glycones and aglycones, for their ability to inhibit topo I and to intercalate DNA using an in vitro gel electrophoresis method. We show that the most potent topo I poisons are the flavones and flavonols, and that these generally, but not always, are found to be DNA intercalators. There was no clear correlation, however, of topo-I-poisoning activity with the degree of DNA unwinding. Surprisingly, both DNA intercalation and topo I poisoning were shown to occur with some flavone glycones, including the C-glycosylflavone orientin. Inhibition of relaxation activity by flavonoids was found to be difficult to quantify and was most likely to be due to non-specific inhibition through flavonoid aggregation. As part of a structure–activity analysis, we also investigated the acid–base chemistry of flavonoids and determined that many flavonoids show acid–base activity with a pKa in the physiological pH region. For this reason, subtle pH changes can have significant effects on solution activity of flavonoids and their concomitant biological activity. In addition, these effects may be complicated by pH-dependent aggregation and oxidative degradation. Finally, we develop a simple model for the intercalation of flavonoids into DNA and discuss possible consequences of intercalation and topoisomerase inhibition on a number of cellular processes.
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Gebhardt, S. E., J. M. Harnly, S. A. Bhagwat, G. R. Beecher, R. F. Doherty, J. M. Holden, D. B. Haytowitz, A. L. Eldridge, J. J. Peterson et J. T. Dwyer. « USDA'S FLAVONOID DATABASE : FLAVONOIDS IN FRUIT ». Journal of the American Dietetic Association 103 (septembre 2003) : 54. http://dx.doi.org/10.1016/s0002-8223(08)70085-3.
Texte intégral
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Vieux, Florent, Matthieu Maillot, Colin D. Rehm et Adam Drewnowski. « Flavonoid Intakes in the US Diet Are Linked to Higher Socioeconomic Status and to Tea Consumption : Analyses of NHANES 2011–16 Data ». Journal of Nutrition 150, no 8 (29 mai 2020) : 2147–55. http://dx.doi.org/10.1093/jn/nxaa145.
Texte intégralRésumé :
ABSTRACT Background Many of the health benefits of tea have been attributed to its flavonoid content. Tea consumption in US adults varies by socioeconomic status (SES). Objectives The present objective was to explore intakes of total flavonoids and flavonoid subclasses by participant sociodemographics and by patterns of tea consumption. Methods The present analyses were based on 2 d of dietary recalls for 17,506 persons aged >9 y in the 2011–2016 NHANES. The What We Eat in America nutrient composition database was merged with the USDA Expanded Flavonoid database, which included total flavonoids and flavan-3-ols (including catechins), flavanones, flavonols, anthocyanidins, flavones, and isoflavones. Flavonoid intakes were compared by sex, age, race/ethnicity, education, and income-to-poverty ratio (IPR) in univariate analyses. Flavonoid intakes of children and adults were also compared by tea consumption status. Time trends in flavonoid intakes were also examined. Results Mean total flavonoid intake was 219 mg/d, of which flavan-3-ols provided 174 mg/d, or 79%. The highest total flavonoid intakes were found in adults aged 51–70 y (293 mg/d), non-Hispanic whites (251 mg/d) and in groups with college education (251 mg/d) and higher income (IPR >3.5: 249 mg/d) (P < 0.001 for all). The socioeconomic gradient was significant for anthocyanidins, flavonols, and flavones (P < 0.001 for all) but not for flavan-3-ols, and persisted across 3 cycles of NHANES. Adult tea consumers had higher intakes of total flavonoids (610 mg/d compared with 141 mg/d) and flavan-3-ols (542 mg/d compared with 97.8 mg/d) than did nonconsumers (P < 0.001). Time trend analyses showed that both tea consumption and flavonoid intakes were unchanged from 2011 to 2016. Conclusions Flavonoid intakes in children and adults in the NHANES 2011–16 sample were associated with higher SES and were largely determined by tea consumption. Studies of diet and disease risk need to take sociodemographic gradients and eating and drinking habits into account.
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Ku, Yee-Shan, Ming-Sin Ng, Sau-Shan Cheng, Annie Wing-Yi Lo, Zhixia Xiao, Tai-Sun Shin, Gyuhwa Chung et Hon-Ming Lam. « Understanding the Composition, Biosynthesis, Accumulation and Transport of Flavonoids in Crops for the Promotion of Crops as Healthy Sources of Flavonoids for Human Consumption ». Nutrients 12, no 6 (8 juin 2020) : 1717. http://dx.doi.org/10.3390/nu12061717.
Texte intégralRésumé :
Flavonoids are a class of polyphenolic compounds that naturally occur in plants. Sub-groups of flavonoids include flavone, flavonol, flavanone, flavanonol, anthocyanidin, flavanol and isoflavone. The various modifications on flavonoid molecules further increase the diversity of flavonoids. Certain crops are famous for being enriched in specific flavonoids. For example, anthocyanins, which give rise to a purplish color, are the characteristic compounds in berries; flavanols are enriched in teas; and isoflavones are uniquely found in several legumes. It is widely accepted that the antioxidative properties of flavonoids are beneficial for human health. In this review, we summarize the classification of the different sub-groups of flavonoids based on their molecular structures. The health benefits of flavonoids are addressed from the perspective of their molecular structures. The flavonoid biosynthesis pathways are compared among different crops to highlight the mechanisms that lead to the differential accumulation of different sub-groups of flavonoids. In addition, the mechanisms and genes involved in the transport and accumulation of flavonoids in crops are discussed. We hope the understanding of flavonoid accumulation in crops will guide the proper balance in their consumption to improve human health.
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Różańska, Dorota, et Bożena Regulska-Ilow. « The importance of flavonoids in reducing blood pressure - selected aspects ». Postępy Higieny i Medycyny Doświadczalnej 73 (27 mars 2019) : 173–81. http://dx.doi.org/10.5604/01.3001.0013.1437.
Texte intégralRésumé :
Hypertension is an independent risk factor for the development of cardiovascular disease. Therapy requires modifying the diet and lifestyle in order to reduce body weight. The role of flavonoids in reducing blood pressure also seems interesting. Flavonoids are plant compounds. The main classes of flavonoids are flavons, isoflavons, flavonols, flavanols, flavanones, and anthocyanins. Numerous epidemiological studies have reported that a higher intake of flavonoids in a diet is associated with a decreased risk of hypertension. One of the mechanisms by which flavonoids can help to reduce blood pressure is their activity as angiotensin-converting enzyme (ACE) inhibitors. Various flavonoids have a different ability to inhibit ACE, which is dependent on their chemical structure. The ACE inhibitor activity is associated with three structural elements of flavonoids: the catechol group on the B-ring, C2-C3 double bond and the cetone group in C4 at the C-ring. Flavonoids may exhibit ACE inhibitor activity because of compete with the substrate (competitive inhibition). One of the studies showed that flavonoid activity, as an ACE inhibitor, may be dependent on the ACE genotype (I/I, I/D, D/D). The vasodilatory properties of flavonoids can help lower blood pressure. Authors of numerous studies have shown that these properties are associated with different mechanisms, e.g. activation of potassium channels, regulation of extracellular and intracellular Ca2+ level, stimulation of nitric oxide synthase and increased synthesis of nitric oxide. Based on the studies presented in this paper, it can be concluded that flavonoids may play an important role both in preventing hypertension and in supporting its treatment.
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Mannen, Ryo, Michiko T. Yasuda, Ayami Sano, Toshinao Goda, Kayoko Shimoi et Yoko Ichikawa. « Changes in plasma concentration of flavonoids after ingestion of a flavonoid-rich meal prepared with basic foodstuffs ». Functional Foods in Health and Disease 9, no 9 (1 octobre 2019) : 558. http://dx.doi.org/10.31989/ffhd.v9i9.643.
Texte intégralRésumé :
Background: As flavonoids have a variety of functions, such as antioxidant activity, there is growing interest in the development of flavonoid supplements. However, there have been reports of DNA damage due to exposure to flavonoids at high concentrations in rats, which could suggest that a habitual intake of flavonoid supplements may cause toxicity. Therefore, we considered that ingesting flavonoids from a typical meal combined basic foodstuffs are safe because of unlikely to result high concentrations like supplements, and focused on the intake of flavonoids from a typical meal. Thus, this study investigated the absorption of flavonoids in humans after the consumption of a typical meal. Methods: On the first 2 days of the study, seven healthy volunteers were provided with low-flavonoid meals (flavonoid content below the detection limit by HPLC: less than 0.24 mg/meal) three times a day as a washout. A flavonoid-rich meal (40.44 ± 1.49 mg/meal) was then provided for breakfast on the third day. Blood was collected from all volunteers 0, 2, 3, 7, 8, and 9 h after the flavonoid-rich meal was consumed. After enzyme hydrolysis of the plasma, the plasma concentrations of flavonoids aglycone of quercetin, daidzein and genistein were measured using LC-MS. Urine was also collected and pooled 24 h after the flavonoid-rich meal was consumed. Thereafter, the urine was treated with enzyme hydrolysis, and the measurement of urinary flavonoids was performed. Results: Plasma flavonoid peaks were observed 8 h after consumption of the flavonoid-rich meal (quercetin: 4.29 ± 1.46 μM, daidzein: 0.51 ± 0.41 μM, genistein: 0.91 ± 0.73 μM). Furthermore, flavonoids were confirmed to be present in plasma even at 9 h after the intake meal. The urinary recovery of flavonoids was 3.43 ± 1.50% for quercetin, 13.87 ± 6.68% for daidzein, and 16.89 ± 11.40% for genistein. Conclusion: These results suggest that consuming a typical meal that combines a variety of basic foodstuffs delays attainment of the plasma flavonoid peak compared with consuming a single type of food or supplements as previously reported. In addition, the flavonoid urinary recovery were also reduced compared with those previously reported.
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Benković, Goran, Mirza Bojić, Željan Maleš et Siniša Tomić. « Screening of flavonoid aglycons’ metabolism mediated by the human liver cytochromes P450 ». Acta Pharmaceutica 69, no 4 (1 décembre 2019) : 541–62. http://dx.doi.org/10.2478/acph-2019-0039.
Texte intégralRésumé :
Abstract Biological effects of flavonoids have been extensively studied in the last 80 years. As flavonoids represent a rather large group of compounds, data on metabolic biotransformations of these compounds is relatively limited to those well studied. The objective of this study was to screen the metabolism of 30 selected flavonoid aglycons mediated by the most relevant metabolic enzymes, human liver cytochromes P450. For this purpose, in vitro experiments with human liver microsomes and recombinant enzymes were conducted. To evaluate flavonoid’s metabolism and structure of the products, high-performance liquid chromatography coupled with high-resolution mass spectrometry was used. Out of 30 flavonoids, 15 were susceptible to oxidative metabolism mediated by cytochromes P450. Dominant reactions were aromatic hydroxylation and O-demethylation, or a combination of these reactions. The dominant enzyme responsible for the observed metabolic reactions is CYP1A2, whereas other human liver cytochromes P450, namely, CYP2C19, CYP2D6, CYP2E1 and CYP3A4, contribute to flavonoid metabolism to a lesser degree. These results, to some extent, contribute to the understanding of the metabolism of constituents found in antioxidant dietary supplements and their possible interactions with other xenobiotics, i.e., medicinal products.
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Wollenweber, Eckhard, Ingrid Schober, Pia Dostal, Dagmar Hradetzky, Francisco J. Arriaga-Giner et George Yatskievych. « Flavonoids and Terpenoids from the Exudates of Some Baccharis Species ». Zeitschrift für Naturforschung C 41, no 1-2 (1 février 1986) : 87–93. http://dx.doi.org/10.1515/znc-1986-1-214.
Texte intégralRésumé :
Abstract Seven species of the genus Baccharis have been analyzed for flavonoid aglycones. Many known methylated flavones, flavonols and flavanones were identified. From B. sarothroides, two novel flavonols were isolated and elucidated as 5,7,4′-trihydroxy-3,6,8-trimethoxyflavone and its methyl ether, 5,4′-dihydroxy-3,6,7,8-tetramethoxyflavone. Previous literature reports on flavonoids in Baccharis are summarized and their distribution and external occurrence is discussed. One novel diterpene and one rare triterpene were found in the terpenoid fractions that constitute most of the exudate material in these and other Compositae.
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Hill, Emily, Anna Pashkova, Elizabeth Grainger, Kristen Roberts, Chureeporn Chitchumroonchokchai, Steven Clinton et Colleen Spees. « Associations Between a Targeted Metabolomics Panel of Urinary Flavonoids and Flavonoid Intakes from Fruits and Vegetables Across Dietary Assessment Periods ». Current Developments in Nutrition 5, Supplement_2 (juin 2021) : 322. http://dx.doi.org/10.1093/cdn/nzab037_032.
Texte intégralRésumé :
Abstract Objectives Aligning dietary intake and food composition data with biomarkers of exposure is critical for advancing assessment methodology. Flavonoids present in fruits and vegetables (FV) are rapidly metabolized and excreted in urine; therefore they may serve as acute intake biomarkers. Yet, the optimal dietary assessment period has not been determined. The objective of this study was to evaluate associations between a targeted metabolomics panel of six urinary flavonoids and dietary intakes of these flavonoids from FV across varying dietary assessment periods. Methods In this cross-sectional study, three-day diet records from 17 individuals were analyzed via Nutrition Data System for Research to determine FV intakes over one-day, two-day, and three-day assessment periods. Dietary flavonoids from FV were estimated via the Phenol-Explorer database; total intakes of targeted flavonoids (quercetin, kaempferol, isorhamnetin, phloretin, naringenin, hesperetin) were calculated by summing aglycone and glycosylated forms. Twenty-four-hour (24-h) urine was collected on the final day of diet records. Urinary flavonoid aglycones were quantified using HPLC; total urinary flavonoids were calculated by summing targeted flavonoids. Spearman correlations between flavonoid intakes and urinary flavonoids were analyzed by dietary assessment period. Results Mean targeted flavonoid intake from FV was 53.6 mg/day. Ten specific FV provided >95% of dietary flavonoids, with greatest contributions from citrus (orange juice, grapefruit, orange) and onion. Mean urinary flavonoid excretion was 9.5 μmol/24-h. Urinary flavonoids were moderately associated with flavonoid intakes from the one-day assessment period on the day prior to urine collection (rs = 0.485, P = 0.048) and summed intakes from the two-day assessment period (rs = 0.598, P = 0.011), but not from intakes over the three-day assessment period. Conclusions Urinary flavonoids are most strongly associated with dietary flavonoids consumed within two days of 24-h urine collection, indicating two-day diet records aligned with 24-h urine collection is optimal for assessing (poly)phenol exposure from FV in future research. Funding Sources OSU CCTS, Rosita Schiller Award, OSU Comprehensive Cancer Center MCC Program, and OSU CAFFRE.
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Jeong, Ju-Mi, Cheol-Hee Choi, Su-Kyeong Kang, In-Hwa Lee, Ji-Yoon Lee et Hyuk Jung. « Antioxidant and Chemosensitizing Effects of Flavonoids with Hydroxy and/or Methoxy Groups and Structure-Activity Relationship ». Journal of Pharmacy & ; Pharmaceutical Sciences 10, no 4 (26 octobre 2007) : 537. http://dx.doi.org/10.18433/j3kw2z.
Texte intégralRésumé :
Purpose. Flavonoids have been used as antioxidant, chemopreventive and chemosensitizing agents. In this study, eleven flavonoids containing a variety of hydroxy (OH) and/or methoxy (OMe) groups were evaluated for their antioxidant, cytotoxic and chemosensitizing effects to create a structure-activity relationship (SAR). Methods. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical solution-based chemical assay and and 2',7'-dichlorofluorescin diacetate (DCFH-DA) cellular-based assay were used to compare the free radical scavenging activity on the same molar concentration basis using the AML-2/DX100 cells which are characterized by the down-regulated expression of catalase and resulting supersensitiviy to hydrogen peroxide. The chemosensitization and cytotoxicity were determined by the MTT assay in the presence or absence of an anticancer drug using the P-glycoprotein-overexpressing AML-2 subline AML-2/D100 cells. Results. The antioxidant activity of the flavonoid (3,5,7,3’,4’-OH) was higher than that of the flavonoid (5,7,3’,4’-OH). Flavonoids substituted with the various number of OMe decreased antioxidant activity. Flavonoids with 7-OH or 5,7-OH groups have the highest cytotoxicity, and flavonoids with 5,7-OMe group intermediate cytotoxicity. The IC50 values of flavonoid (5,7-OMe, 3’,4’,5’-OMe) and flavonoid (5,7-OMe, 4’-OMe), 0.4 M and 1.4 M. The IC50 values of flavonoid (5,6,7-OMe, 3’,4’-OMe) and flavonoid (5,6,7-OMe, 3’,4’,5’-OMe), 3.2 uM and 0.9 M, respectively, and those of flavonoid (5,6,7-OMe, 3’,4’,5’-OMe) and flavonoid (5,7-OMe,3’,4’,5’-OMe) were 0.9 M and 0.4 M, respectively. Conclusions. These results suggest that flavonoids with 3-OH group play a positive role in antioxidant activities, flavonoids with 5-OH and/or 7-OH groups show the higher cytotoxicity, and flavonoids with 3’-OMe and/or 5’-OMe groups plays positive but 6-OMe groups negative roles in the P-glycoprotein (Pgp) inhibition. It is believed that these SAR results can be taken into account for the development of flavonoids with high therapeutic index.
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Li, Xiao Lei, et Dan Li. « Analysis of Tartary Buckwheat Flavonoids Using Electrospray Ionization Tandem Mass Spectrometry ». Advanced Materials Research 393-395 (novembre 2011) : 597–600. http://dx.doi.org/10.4028/www.scientific.net/amr.393-395.597.
Texte intégralRésumé :
Four flavonoid compounds from the tartary buckwheat grains were purified by hydrated ethanol extraction and chromatography isolation. Their ion fragments and mass-to-charge ratios were obtained using electrospray ionization tandem mass spectrometry, respectively. The four flavonoids were identified as flavonols, quercetin 3-O-rutinoside-3'-O-β-glucopyranoside, rutin, kaempferol 3-O-rutinoside, and quercetin.
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Pallauf, Kathrin, Nils Duckstein, Mario Hasler, Lars-Oliver Klotz et Gerald Rimbach. « Flavonoids as Putative Inducers of the Transcription Factors Nrf2, FoxO, and PPARγ ». Oxidative Medicine and Cellular Longevity 2017 (2017) : 1–11. http://dx.doi.org/10.1155/2017/4397340.
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Dietary flavonoids have been shown to extend the lifespan of some model organisms and may delay the onset of chronic ageing-related diseases. Mechanistically, the effects could be explained by the compounds scavenging free radicals or modulating signalling pathways. Transcription factors Nrf2, FoxO, and PPARγpossibly affect ageing by regulating stress response, adipogenesis, and insulin sensitivity. Using Hek-293 cells transfected with luciferase reporter constructs, we tested the potency of flavonoids from different subclasses (flavonols, flavones, flavanols, and isoflavones) to activate these transcription factors. Under cell-free conditions (ABTS and FRAP assays), we tested their free radical scavenging activities and usedα-tocopherol and ascorbic acid as positive controls. Most of the tested flavonoids, but not the antioxidant vitamins, stimulated Nrf2-, FoxO-, and PPARγ-dependent promoter activities. Flavonoids activating Nrf2 also tended to induce a FoxO and PPARγresponse. Interestingly, activation patterns of cellular stress response by flavonoids were not mirrored by their activities in ABTS and FRAP assays, which depended mostly on hydroxylation in the flavonoid B ring and, in some cases, extended that of the vitamins. In conclusion, the free radical scavenging properties of flavonoids do not predict whether these molecules can stimulate a cellular response linked to activation of longevity-associated transcription factors.
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Gao, Gang, Ping Chen, Jikang Chen, Kunmei Chen, Xiaofei Wang, Aminu Shehu Abubakar, Ning Liu, Chunming Yu et Aiguo Zhu. « Genomic Survey, Transcriptome, and Metabolome Analysis of Apocynum venetum and Apocynum hendersonii to Reveal Major Flavonoid Biosynthesis Pathways ». Metabolites 9, no 12 (5 décembre 2019) : 296. http://dx.doi.org/10.3390/metabo9120296.
Texte intégralRésumé :
Apocynum plants, especially A. venetum and A. hendersonii, are rich in flavonoids. In the present study, a whole genome survey of the two species was initially carried out to optimize the flavonoid biosynthesis-correlated gene mining. Then, the metabolome and transcriptome analyses were combined to elucidate the flavonoid biosynthesis pathways. Both species have small genome sizes of 232.80 Mb (A. venetum) and 233.74 Mb (A. hendersonii) and showed similar metabolite profiles with flavonols being the main differentiated flavonoids between the two specie. Positive correlation of gene expression levels (flavonone-3 hydroxylase, anthocyanidin reductase, and flavonoid 3-O-glucosyltransferase) and total flavonoid content were observed. The contents of quercitrin, hyperoside, and total anthocyanin in A. venetum were found to be much higher than in A. hendersonii, and such was thought to be the reason for the morphological difference in color of A. venetum and A. hendersonii. This study provides valuable genomic and metabolome information for understanding of A. venetum and A. hendersonii, and lays a foundation for elucidating Apocynum genus plant flavonoid biosynthesis.
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Yeh, Tian-Shin, Changzheng Yuan, Alberto Ascherio, Bernard A. Rosner, Walter C. Willett et Deborah Blacker. « Long-term Dietary Flavonoid Intake and Subjective Cognitive Decline in US Men and Women ». Neurology 97, no 10 (28 juillet 2021) : e1041-e1056. http://dx.doi.org/10.1212/wnl.0000000000012454.
Texte intégralRésumé :
ObjectiveTo prospectively examine the associations between long-term dietary flavonoids and subjective cognitive decline (SCD).MethodsWe followed 49,493 women from the Nurses' Health Study (NHS) (1984–2006) and 27,842 men from the Health Professionals Follow-Up Study (HPFS) (1986–2002). Poisson regression was used to evaluate the associations between dietary flavonoids (flavonols, flavones, flavanones, flavan-3-ols, anthocyanins, polymeric flavonoids, and proanthocyanidins) and subsequent SCD. For the NHS, long-term average dietary intake was calculated from 7 repeated semiquantitative food frequency questionnaires (SFFQs), and SCD was assessed in 2012 and 2014. For the HPFS, average dietary intake was calculated from 5 repeated SFFQs, and SCD was assessed in 2008 and 2012.ResultsHigher intake of total flavonoids was associated with lower odds of SCD after adjustment for age, total energy intake, major nondietary factors, and specific dietary factors. In a comparison of the highest vs the lowest quintiles of total flavonoid intake, the pooled multivariable-adjusted odds ratio (OR) of 3-unit increments in SCD was 0.81 (95% confidence interval [CI] 0.76, 0.89). In the pooled results, the strongest associations were observed for flavones (OR 0.62 [95% CI 0.57, 0.68]), flavanones (0.64 [0.58, 0.68)]), and anthocyanins (0.76 [0.72, 0.84]) (p trend <0.001 for all groups). The dose-response curve was steepest for flavones, followed by anthocyanins. Many flavonoid-rich foods such as strawberries, oranges, grapefruits, citrus juices, apples/pears, celery, peppers, and bananas, were significantly associated with lower odds of SCD.ConclusionOur findings support a benefit of higher flavonoid intakes for maintaining cognitive function in US men and women.
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Nicholls, K. W., B. A. Bohm et E. F. Wells. « The flavonoids of Mitella, Bensoniella, and Conimitella (Saxifragaceae) ». Canadian Journal of Botany 64, no 3 (1 mars 1986) : 525–30. http://dx.doi.org/10.1139/b86-067.
Texte intégralRésumé :
Flavonoid profiles have been determined for 16 species of Mitella and for the two monotypic genera, Bensoniella and Conimitella. With a single exception the profiles are based upon the flavonols kaempferol, quercetin, and myricetin. The flavanone eriodictyol was seen in two Japanese species of Mitella. The flavonols exist as a series of 7-O-mono-, 3-O-mono-, 3-O-di-, and 3-O-triglycosides, although not all levels of glycosylation occur in each taxon. 7-O-Methylkaempferol and 7-O-methylquercetin were found in M. nuda and M. diphylla; M. nuda also has isorhamnetin. The flavonoids of M. nuda are unique in the genus, but otherwise the distribution of the pigments does not offer support for Rydberg's view of the species being assigned to four genera or Rosendahl's view that Mitella comprises two sections. The flavonoid profile of Bensoniella oregona clearly distinguishes it from Mitella. Flavonoid data for Conimitella williamsii agree in general with those of a moderately advanced species of Heuchera in agreement with Savile's views on the origin of Conimitella. Our results are discussed in terms of the recent finding that Conimitella and Mitella form natural hybrids.
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Tomás-Barberán, F. A., F. Ferreres, F. Tomás-Lorente et A. Ortiz. « Flavonoids from Apis mellifera Beeswax ». Zeitschrift für Naturforschung C 48, no 1-2 (1 février 1993) : 68–72. http://dx.doi.org/10.1515/znc-1993-1-213.
Texte intégralRésumé :
The flavonoids present in beeswax produced in “La Alcarria” region were analyzed by HPLC. Pinocembrin, pinobanksin, pinobanksin 3-acetate, chrysin, galangin and techtochrysin were detected as the main flavonoid constituents. This is the first detailed report on the flavonoids of beeswax. These substances are already present when wax scales are secreted by bees. The same flavonoid compounds were generally present in honey, propolis and Populus nigra bud exudates collected in the same geographical region. These results indicate that beeswax flavonoids originate from those of honey and/or propolis, and suggest that analysis of beeswax flavonoids could be used as an adjunct in the detection of beeswax adulterations.
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Ryan, Ken G., Ewald E. Swinny, Chris Winefield et Kenneth R. Markham. « Flavonoids and UV Photoprotection in Arabidopsis Mutants ». Zeitschrift für Naturforschung C 56, no 9-10 (1 octobre 2001) : 745–54. http://dx.doi.org/10.1515/znc-2001-9-1013.
Texte intégralRésumé :
AbstractWild-type Arabidopsis L. leaves exposed to low ultraviolet-B (U V B ) conditions contained predominantly kaempferol glycosides, with low levels of quercetin glycosides. The flavonoid level doubled on treatment with UVB and an increase in the ratio of quercetin: kaempferol was observed. These results suggest that flavonols protect Arabidopsis plants from UVB damage, and indicate that the flavonoid 3’-hydroxylase (F3’H) enzyme, which converts dihydrokaempferol to dihydroquercetin, may play a crucial role. The tt7 mutant lacks this gene and, after treatment with sub-ambient UVB, contained kaempferol glycosides exclusively, to a level of total flavonols similar to that in wild-type Arabidopsis. Total flavonols after enhanced UVB treatment were higher in tt7 than in similarly treated wild-type plants, and only kaempferol glycosides were detected. Despite this high level, tt7 plants were less tolerant of UVB radiation than wild-type plants. These observations suggests that kaempferol is a less effective photoprotectant than quercetin. The chalcone isomerase (CHI) mutant (tt5) surprisingly did not accumulate naringenin chalcone, and this suggests that the mutation may not be restricted to the CHI gene alone. The concentration of hydroxycinnamic acid derivatives did not change with UVB treatment in most varieties indicating that their role in UV photoprotection may be subordinate to that of the flavonoids.
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Joyner, P. Matthew. « Protein Adducts and Protein Oxidation as Molecular Mechanisms of Flavonoid Bioactivity ». Molecules 26, no 16 (23 août 2021) : 5102. http://dx.doi.org/10.3390/molecules26165102.
Texte intégralRésumé :
There are tens of thousands of scientific papers about flavonoids and their impacts on human health. However, despite the vast amount of energy that has been put toward studying these compounds, a unified molecular mechanism that explains their bioactivity remains elusive. One contributing factor to the absence of a general mechanistic explanation of their bioactivity is the complexity of flavonoid chemistry in aqueous solutions at neutral pH. Flavonoids have acidic protons, are redox active, and frequently auto-oxidize to produce an array of degradation products including electrophilic quinones. Flavonoids are also known to interact with specificity and high affinity with a variety of proteins, and there is evidence that some of these interactions may be covalent. This review summarizes the mechanisms of flavonoid oxidation in aqueous solutions at neutral pH and proposes the formation of protein-flavonoid adducts or flavonoid-induced protein oxidation as putative mechanisms of flavonoid bioactivity in cells. Nucleophilic residues in proteins may be able to form covalent bonds with flavonoid quinones; alternatively, specific amino acid residues such as cysteine, methionine, or tyrosine in proteins could be oxidized by flavonoids. In either case, these protein-flavonoid interactions would likely occur at specific binding sites and the formation of these types of products could effectively explain how flavonoids modify proteins in cells to induce downstream biochemical and cellular changes.
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Ma, Dawei, Hao Tang, Michael Reichelt, Eerik-Mikael Piirtola, Juha-Pekka Salminen, Jonathan Gershenzon et C. Peter Constabel. « Poplar MYB117 promotes anthocyanin synthesis and enhances flavonoid B-ring hydroxylation by up-regulating the flavonoid 3′,5′-hydroxylase gene ». Journal of Experimental Botany 72, no 10 (12 mars 2021) : 3864–80. http://dx.doi.org/10.1093/jxb/erab116.
Texte intégralRésumé :
Abstract Flavonoids, such as anthocyanins, proanthocyanidins, and flavonols, are widespread plant secondary metabolites and important for plant adaptation to diverse abiotic and biotic stresses. Flavonoids can be variously hydroxylated and decorated; their biological activity is partly dependent on the degree of hydroxylation of the B-ring. Flavonoid biosynthesis is regulated by MYB transcription factors, which have been identified and characterized in a diversity of plants. Here we characterize a new MYB activator, MYB117, in hybrid poplar (Populus tremula×tremuloides). When overexpressed in transgenic poplar plants, MYB117 enhanced anthocyanin accumulation in all tissues. Transcriptome analysis of MYB117-overexpressing poplars confirmed the up-regulation of flavonoid and anthocyanin biosynthesis genes, as well as two flavonoid 3′,5′-hydroxylase (F3′5′H) genes. We also identified up-regulated cytochrome b5 genes, required for full activity of F3′5′H . Phytochemical analysis demonstrated a corresponding increase in B-ring hydroxylation of anthocyanins, proanthocyanidins, and flavonols in these transgenics. Similarly, overexpression of F3′5′H1 directly in hybrid poplar also resulted in increased B-ring hydroxylation, but without affecting overall flavonoid content. However, the overexpression of the cytochrome b5 gene in F3′5′H1-overexpressing plants did not further increase B-ring hydroxylation. Our data indicate that MYB117 regulates the biosynthesis of anthocyanins in poplar, but also enhances B-ring hydroxylation by up-regulating F3′5′H1.
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Mottaghipisheh, Javad, et Marcello Iriti. « Sephadex® LH-20, Isolation, and Purification of Flavonoids from Plant Species : A Comprehensive Review ». Molecules 25, no 18 (10 septembre 2020) : 4146. http://dx.doi.org/10.3390/molecules25184146.
Texte intégralRésumé :
Flavonoids are considered one of the most diverse phenolic compounds possessing several valuable health benefits. The present study aimed at gathering all correlated reports, in which Sephadex® LH-20 (SLH) has been utilized as the final step to isolate or purify of flavonoid derivatives among all plant families. Overall, 189 flavonoids have been documented, while the majority were identified from the Asteraceae, Moraceae, and Poaceae families. Application of SLH has led to isolate 79 flavonols, 63 flavones, and 18 flavanones. Homoisoflavanoids, and proanthocyanidins have only been isolated from the Asparagaceae and Lauraceae families, respectively, while the Asteraceae was the richest in flavones possessing 22 derivatives. Six flavones, four flavonols, three homoisoflavonoids, one flavanone, a flavanol, and an isoflavanol have been isolated as the new secondary metabolites. This technique has been able to isolate quercetin from 19 plant species, along with its 31 derivatives. Pure methanol and in combination with water, chloroform, and dichloromethane have generally been used as eluents. This comprehensive review provides significant information regarding to remarkably use of SLH in isolation and purification of flavonoids from all the plant families; thus, it might be considered an appreciable guideline for further phytochemical investigation of these compounds.
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Atrahimovich, Dana, Dorit Avni et Soliman Khatib. « Flavonoids-Macromolecules Interactions in Human Diseases with Focus on Alzheimer, Atherosclerosis and Cancer ». Antioxidants 10, no 3 (10 mars 2021) : 423. http://dx.doi.org/10.3390/antiox10030423.
Texte intégralRésumé :
Flavonoids, a class of polyphenols, consumed daily in our diet, are associated with a reduced risk for oxidative stress (OS)-related chronic diseases, such as cardiovascular disease, neurodegenerative diseases, cancer, and inflammation. The involvement of flavonoids with OS-related chronic diseases have been traditionally attributed to their antioxidant activity. However, evidence from recent studies indicate that flavonoids’ beneficial impact may be assigned to their interaction with cellular macromolecules, rather than exerting a direct antioxidant effect. This review provides an overview of the recent evolving research on interactions between the flavonoids and lipoproteins, proteins, chromatin, DNA, and cell-signaling molecules that are involved in the OS-related chronic diseases; it focuses on the mechanisms by which flavonoids attenuate the development of the aforementioned chronic diseases via direct and indirect effects on gene expression and cellular functions. The current review summarizes data from the literature and from our recent research and then compares specific flavonoids’ interactions with their targets, focusing on flavonoid structure–activity relationships. In addition, the various methods of evaluating flavonoid–protein and flavonoid–DNA interactions are presented. Our aim is to shed light on flavonoids action in the body, beyond their well-established, direct antioxidant activity, and to provide insights into the mechanisms by which these small molecules, consumed daily, influence cellular functions.
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Averett, John E., William J. Hahn, Paul E. Berry et Peter H. Raven. « FLAVONOIDS AND FLAVONOID EVOLUTION IN FUCHSIA (ONAGRACEAE) ». American Journal of Botany 73, no 11 (novembre 1986) : 1525–34. http://dx.doi.org/10.1002/j.1537-2197.1986.tb10902.x.
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Yang, Yun, Mengjiao Chen, Yaxin Liu, Huanhuan Ding, Hongyan Du, Zhiqiang Sun et Jingle Zhu. « Metabolome and Transcriptome Analyses Reveal Different Flavonoid Biosynthesis and Chlorophyll Metabolism Profiles between Red Leaf and Green Leaf of Eucommia ulmoides ». Forests 12, no 9 (16 septembre 2021) : 1260. http://dx.doi.org/10.3390/f12091260.
Texte intégralRésumé :
Flavonoids are natural antioxidants in plants that affect the color of plant tissues. Flavonoids can be divided into eight subgroups, including flavonols, anthocyanins, and proanthocyanidins. The mechanisms of flavonoid synthesis in model plants have been widely studied. However, there are a limited number of reports on the synthesis of flavonoids in the red leaf varieties of woody plants. In this study, we combined morphological observation, pigment content determination, metabolomics, and transcriptomics to investigate the metabolites and gene regulation present in the red and green leaves of Eucommia ulmoides Oliv. The results showed that the red leaves have a lower chlorophyll content and a higher anthocyanin content. Metabonomic analysis identified that the relative content of most flavonoids is up-regulated in red leaves based on UPLC-ESI-MS/MS, which included the apigenin class, quercetin class, kaempferol class, and procyanidins. Transcriptome data suggested that the differentially up-regulated genes are enriched in flavonoid and anthocyanin synthesis pathways, ABC transport, and GST pathways. The integrative analysis of the transcriptome and metabolome showed that the up-regulation of flavonoid metabolism and a high expression of chlorophyll degradation with the down-regulation of chlorophyll biosynthesis genes are detected in E. ulmoides red leaves compared with green leaves. In addition, the co-expression networks implied that cyanidin 3-5-O-diglucoside, EuDR5, EuPAL2, EuDFR11, Eu3MaT1, and EuF3′H are likely associated with the red leaf coloration of E. ulmoides. In summary, this research provided a reference for studying the mechanism of red leaf coloration in woody plants and the use of E. ulmoides red leaves as feedstock for bioactive products.
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Jeong, Yu-Jin, Yean-Jung Choi, Hyang-Mi Kwon, Sang-Wook Kang, Hyoung-Sook Park, Myungsook Lee et Young-Hee Kang. « Differential inhibition of oxidized LDL-induced apoptosis in human endothelial cells treated with different flavonoids ». British Journal of Nutrition 93, no 5 (mai 2005) : 581–91. http://dx.doi.org/10.1079/bjn20041397.
Texte intégralRésumé :
High plasma level of cholesterol is a well-known risk factor for atherosclerotic diseases. Oxidized LDL induces cellular and nuclear damage that leads to apoptotic cell death. We tested the hypothesis that flavonoids may function as antioxidants with regard to LDL incubated with 5 μm-Cu2+ alone or in combination with human umbilical vein endothelial cells (HUVEC). Cytotoxicity and formation of thiobarbituric acid-reactive substances induced by Cu2+-oxidized LDL were examined in the presence of various subtypes of flavonoid. Flavanols, flavonols and flavanones at a non-toxic dose of 50 μm markedly inhibited LDL oxidation by inhibiting the formation of peroxidative products. In contrast, the flavones luteolin and apigenin had no such effect, with >30 % of cells killed after exposure to 0.1 mg LDL/ml. Protective flavonoids, especially (−)-epigallocatechin gallate, quercetin, rutin and hesperetin, inhibited HUVEC nuclear condensation and fragmentation induced by Cu2+-oxidized LDL. In addition, immunochemical staining and Western blot analysis revealed that anti-apoptotic Bcl-2 expression was enhanced following treatment with these protective flavonoids. However, Bax expression and caspase-3 cleavage stimulated by 18 h incubation with oxidized LDL were reduced following treatment with these protective flavonoids. The down-regulation of Bcl-2 and up-regulation of caspase-3 activation were reversed by the cytoprotective flavonoids, (−)-epigallocatechin gallate, quercetin and hesperetin, at ≥10 μm. These results suggest that flavonoids may differentially prevent Cu2+-oxidized LDL-induced apoptosis and promote cell survival as potent antioxidants. Survival potentials of certain flavonoids against cytotoxic oxidized LDL appeared to stem from their disparate chemical structure. Furthermore, dietary flavonoids may have therapeutic potential for protecting the endothelium from oxidative stress and oxidized LDL-triggered atherogenesis.