[Advance in flavonoids biosynthetic pathway and synthetic biology].

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Zou, Li-Qiu; Wang, Cai-Xia; Kuang, Xue-Jun; Li, Ying; Sun, Chao

2016-11-01

Flavonoids are the valuable components in medicinal plants, which possess a variety of pharmacological activities, including anti-tumor, antioxidant and anti-inflammatory activities. There is an unambiguous understanding about flavonoids biosynthetic pathway, that is,2S-flavanones including naringenin and pinocembrin are the skeleton of other flavonoids and they can transform to other flavonoids through branched metabolic pathway. Elucidation of the flavonoids biosynthetic pathway lays a solid foundation for their synthetic biology. A few flavonoids have been produced in Escherichia coli or yeast with synthetic biological technologies, such as naringenin, pinocembrin and fisetin. Synthetic biology will provide a new way to get valuable flavonoids and promote the research and development of flavonoid drugs and health products, making flavonoids play more important roles in human diet and health. Copyright© by the Chinese Pharmaceutical Association.

Structure, bioactivity, and synthesis of methylated flavonoids.

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Wen, Lingrong; Jiang, Yueming; Yang, Jiali; Zhao, Yupeng; Tian, Miaomiao; Yang, Bao

2017-06-01

Methylated flavonoids are an important type of natural flavonoid derivative with potentially multiple health benefits; among other things, they have improved bioavailability compared with flavonoid precursors. Flavonoids have been documented to have broad bioactivities, such as anticancer, immunomodulation, and antioxidant activities, that can be elevated, to a certain extent, by methylation. Understanding the structure, bioactivity, and bioavailability of methylated flavonoids, therefore, is an interesting topic with broad potential applications. Though methylated flavonoids are widely present in plants, their levels are usually low. Because developing efficient techniques to produce these chemicals would likely be beneficial, we provide an overview of their chemical and biological synthesis. © 2017 New York Academy of Sciences.

Recent discoveries of anticancer flavonoids.

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Raffa, Demetrio; Maggio, Benedetta; Raimondi, Maria Valeria; Plescia, Fabiana; Daidone, Giuseppe

2017-12-15

In this review we report the recent advances in anticancer activity of the family of natural occurring flavonoids, covering the time span of the last five years. The bibliographic data will be grouped, on the basis of biological information, in two great categories: reports in which the extract plants bioactivity is reported and the identification of each flavonoid is present or not, and reports in which the anticancer activity is attributable to purified and identified flavonoids from plants. Wherever possible, the targets and mechanisms of action as well as the structure-activity relationships of the molecules will be reported. Also, in the review it was thoroughly investigated the recent discovery on flavonoids containing the 2-phenyl-4H-chromen-4-one system even if some examples of unusual flavonoids, bearing a non-aromatic B-ring or other ring condensed to the base structure are reported. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Analysis of flavonoids and the flavonoid structural genes in brown fiber of upland cotton.

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Hongjie Feng

Full Text Available BACKGROUND: As a result of changing consumer preferences, cotton (Gossypium Hirsutum L. from varieties with naturally colored fibers is becoming increasingly sought after in the textile industry. The molecular mechanisms leading to colored fiber development are still largely unknown, although it is expected that the color is derived from flavanoids. EXPERIMENTAL DESIGN: Firstly, four key genes of the flavonoid biosynthetic pathway in cotton (GhC4H, GhCHS, GhF3'H, and GhF3'5'H were cloned and studied their expression profiles during the development of brown- and white cotton fibers by QRT-PCR. And then, the concentrations of four components of the flavonoid biosynthetic pathway, naringenin, quercetin, kaempferol and myricetin in brown- and white fibers were analyzed at different developmental stages by HPLC. RESULT: The predicted proteins of the four flavonoid structural genes corresponding to these genes exhibit strong sequence similarity to their counterparts in various plant species. Transcript levels for all four genes were considerably higher in developing brown fibers than in white fibers from a near isogenic line (NIL. The contents of four flavonoids (naringenin, quercetin, kaempferol and myricetin were significantly higher in brown than in white fibers and corresponding to the biosynthetic gene expression levels. CONCLUSIONS: Flavonoid structural gene expression and flavonoid metabolism are important in the development of pigmentation in brown cotton fibers.

Analysis and health effects of flavonoids.

NARCIS (Netherlands)

Hollman, P.C.H.; Hertog, M.G.L.; Katan, M.B.

1996-01-01

Flavonoids are polyphenolic compounds that occur ubiquitously in foods of plant origin. Over 4000 different flavonoids have been described. Flavonoids have a variety of biological effects in numerous mammalian cell systems, in vitro as well as in vivo. Recently much attention has been paid to their

Flavonoids from each of the six structural groups reactivate BRM, a possible cofactor for the anticancer effects of flavonoids

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Kahali, Bhaskar; Marquez, Stefanie B.; Thompson, Kenneth W.; Yu, Jinlong; Gramling, Sarah J.B.; Lu, Li; Aponick, Aaron; Reisman, David

2014-01-01

Flavonoids have been extensively studied and are well documented to have anticancer effects, but it is not entirely known how they impact cellular mechanisms to elicit these effects. In the course of this study, we found that a variety of different flavonoids readily restored Brahma (BRM) in BRM-deficient cancer cell lines. Flavonoids from each of the six different structural groups were effective at inducing BRM expression as well as inhibiting growth in these BRM-deficient cancer cells. By blocking the induction of BRM with shRNA, we found that flavonoid-induced growth inhibition was BRM dependent. We also found that flavonoids can restore BRM functionality by reversing BRM acetylation. In addition, we observed that an array of natural flavonoid-containing products both induced BRM expression as well as deacetylated the BRM protein. We also tested two of the BRM-inducing flavonoids (Rutin and Diosmin) at both a low and a high dose on the development of tumors in an established murine lung cancer model. We found that these flavonoids effectively blocked development of adenomas in the lungs of wild-type mice but not in that of BRMnull mice. These data demonstrate that BRM expression and function are regulated by flavonoids and that functional BRM appears to be a prerequisite for the anticancer effects of flavonoids both in vitro and in vivo. PMID:24876151

Probabilistic record linkage.

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Sayers, Adrian; Ben-Shlomo, Yoav; Blom, Ashley W; Steele, Fiona

2016-06-01

Studies involving the use of probabilistic record linkage are becoming increasingly common. However, the methods underpinning probabilistic record linkage are not widely taught or understood, and therefore these studies can appear to be a 'black box' research tool. In this article, we aim to describe the process of probabilistic record linkage through a simple exemplar. We first introduce the concept of deterministic linkage and contrast this with probabilistic linkage. We illustrate each step of the process using a simple exemplar and describe the data structure required to perform a probabilistic linkage. We describe the process of calculating and interpreting matched weights and how to convert matched weights into posterior probabilities of a match using Bayes theorem. We conclude this article with a brief discussion of some of the computational demands of record linkage, how you might assess the quality of your linkage algorithm, and how epidemiologists can maximize the value of their record-linked research using robust record linkage methods. © The Author 2015; Published by Oxford University Press on behalf of the International Epidemiological Association.

Gene Expression and Metabolite Profiling of Developing Highbush Blueberry Fruit Indicates Transcriptional Regulation of Flavonoid Metabolism and Activation of Abscisic Acid Metabolism1[W][OA

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Zifkin, Michael; Jin, Alena; Ozga, Jocelyn A.; Zaharia, L. Irina; Schernthaner, Johann P.; Gesell, Andreas; Abrams, Suzanne R.; Kennedy, James A.; Constabel, C. Peter

2012-01-01

Highbush blueberry (Vaccinium corymbosum) fruits contain substantial quantities of flavonoids, which are implicated in a wide range of health benefits. Although the flavonoid constituents of ripe blueberries are known, the molecular genetics underlying their biosynthesis, localization, and changes that occur during development have not been investigated. Two expressed sequence tag libraries from ripening blueberry fruit were constructed as a resource for gene identification and quantitative real-time reverse transcription-polymerase chain reaction primer design. Gene expression profiling by quantitative real-time reverse transcription-polymerase chain reaction showed that flavonoid biosynthetic transcript abundance followed a tightly regulated biphasic pattern, and transcript profiles were consistent with the abundance of the three major classes of flavonoids. Proanthocyanidins (PAs) and corresponding biosynthetic transcripts encoding anthocyanidin reductase and leucoanthocyanidin reductase were most concentrated in young fruit and localized predominantly to the inner fruit tissue containing the seeds and placentae. Mean PA polymer length was seven to 8.5 subunits, linked predominantly via B-type linkages, and was relatively constant throughout development. Flavonol accumulation and localization patterns were similar to those of the PAs, and the B-ring hydroxylation pattern of both was correlated with flavonoid-3′-hydroxylase transcript abundance. By contrast, anthocyanins accumulated late in maturation, which coincided with a peak in flavonoid-3-O-glycosyltransferase and flavonoid-3′5′-hydroxylase transcripts. Transcripts of VcMYBPA1, which likely encodes an R2R3-MYB transcriptional regulator of PA synthesis, were prominent in both phases of development. Furthermore, the initiation of ripening was accompanied by a substantial rise in abscisic acid, a growth regulator that may be an important component of the ripening process and contribute to the regulation

Antiartherosclerotic Effects of Plant Flavonoids

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Shamala Salvamani

2014-01-01

Full Text Available Atherosclerosis is the process of hardening and narrowing the arteries. Atherosclerosis is generally associated with cardiovascular diseases such as strokes, heart attacks, and peripheral vascular diseases. Since the usage of the synthetic drug, statins, leads to various side effects, the plants flavonoids with antiartherosclerotic activity gained much attention and were proven to reduce the risk of atherosclerosis in vitro and in vivo based on different animal models. The flavonoids compounds also exhibit lipid lowering effects and anti-inflammatory and antiatherogenic properties. The future development of flavonoids-based drugs is believed to provide significant effects on atherosclerosis and its related diseases. This paper discusses the antiatherosclerotic effects of selected plant flavonoids such as quercetin, kaempferol, myricetin, rutin, naringenin, catechin, fisetin, and gossypetin.

Different biosynthesis patterns among flavonoid 3-glycosides with distinct effects on accumulation of other flavonoid metabolites in pears (Pyrus bretschneideri Rehd..

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Rui Zhai

Full Text Available Flavonoid biosynthesis profile was clarified by fruit bagging and re-exposure treatments in the green Chinese pear 'Zaosu' (Pyrus bretschneideri Rehd. and its red mutant 'Red Zaosu'. Two distinct biosynthesis patterns of flavonoid 3-glycosides were found in 'Zaosu' pear. By comparison with 'Red Zaosu', the biosynthesis of flavonoid 3-galactosides and flavonoid 3-arabinosides were inhibited by bagging and these compounds only re-accumulated to a small degree in the fruit peel of 'Zaosu' after the bags were removed. In contrast, the biosynthesis of flavonoid 3-gluctosides and flavonoid 3-rutinosides was reduced by bagging and then increased when the fruits were re-exposed to sunlight. A combination of correlation, multicollinearity test and partial-correlation analyses among major flavonoid metabolites indicated that biosynthesis of each phenolic compound was independent in 'Zaosu' pear, except for the positive correlation between flavonoid 3-rutincosides and flavanols. In contrast with the green pear cultivar, almost all phenolic compounds in the red mutant had similar biosynthesis patterns except for arbutin. However, only the biosynthesis of flavonoid 3-galactosides was relatively independent and strongly affected the synthesis of the other phenolic compounds. Therefore, we propose a hypothesis that the strong accumulation of flavonoid 3-galactosides stimulated the biosynthesis of other flavonoid compounds in the red mutant and, therefore, caused systemic variation of flavonoid biosynthesis profiles between 'Zaosu' and its red mutant. This hypothesis had been further demonstrated by the enzyme activity of UFGT, and transcript levels of flavonoid biosynthetic genes and been well tested by a stepwise linear regression forecasting model. The gene that encodes flavonoid 3-galacosyltransferase was also identified and isolated from the pear genome.

Chemistry and Biological Activities of Flavonoids: An Overview

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Shashank Kumar

2013-01-01

Full Text Available There has been increasing interest in the research on flavonoids from plant sources because of their versatile health benefits reported in various epidemiological studies. Since flavonoids are directly associated with human dietary ingredients and health, there is need to evaluate structure and function relationship. The bioavailability, metabolism, and biological activity of flavonoids depend upon the configuration, total number of hydroxyl groups, and substitution of functional groups about their nuclear structure. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. Most recent researches have focused on the health aspects of flavonoids for humans. Many flavonoids are shown to have antioxidative activity, free radical scavenging capacity, coronary heart disease prevention, hepatoprotective, anti-inflammatory, and anticancer activities, while some flavonoids exhibit potential antiviral activities. In plant systems, flavonoids help in combating oxidative stress and act as growth regulators. For pharmaceutical purposes cost-effective bulk production of different types of flavonoids has been made possible with the help of microbial biotechnology. This review highlights the structural features of flavonoids, their beneficial roles in human health, and significance in plants as well as their microbial production.

Chemistry and Biological Activities of Flavonoids: An Overview

Science.gov (United States)

Kumar, Shashank; Pandey, Abhay K.

2013-01-01

There has been increasing interest in the research on flavonoids from plant sources because of their versatile health benefits reported in various epidemiological studies. Since flavonoids are directly associated with human dietary ingredients and health, there is need to evaluate structure and function relationship. The bioavailability, metabolism, and biological activity of flavonoids depend upon the configuration, total number of hydroxyl groups, and substitution of functional groups about their nuclear structure. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. Most recent researches have focused on the health aspects of flavonoids for humans. Many flavonoids are shown to have antioxidative activity, free radical scavenging capacity, coronary heart disease prevention, hepatoprotective, anti-inflammatory, and anticancer activities, while some flavonoids exhibit potential antiviral activities. In plant systems, flavonoids help in combating oxidative stress and act as growth regulators. For pharmaceutical purposes cost-effective bulk production of different types of flavonoids has been made possible with the help of microbial biotechnology. This review highlights the structural features of flavonoids, their beneficial roles in human health, and significance in plants as well as their microbial production. PMID:24470791

Flavonoids and terpenoids from Helichrysum forskahlii.

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Al-Rehaily, Adnan J; Albishi, Omar A; El-Olemy, Mahmoud M; Mossa, Jaber S

2008-06-01

Three new flavonoids, namely helichrysone A (1), helichrysone B (2) and helichrysone C (3) were isolated from the aerial parts of Helichrysum forskahlii, together with 10 known flavonoids, three triterpenes, and one sesquiterpene. The structures of the new flavonoids 1-3 were established by 1D and 2D NMR spectral data. In addition, the antimicrobial activities of the isolated compounds were determined.

Flavonoid Bioavailability and Attempts for Bioavailability Enhancement

Science.gov (United States)

Thilakarathna, Surangi H.; Rupasinghe, H. P. Vasantha

2013-01-01

Flavonoids are a group of phytochemicals that have shown numerous health effects and have therefore been studied extensively. Of the six common food flavonoid classes, flavonols are distributed ubiquitously among different plant foods whereas appreciable amounts of isoflavones are found in leguminous plant-based foods. Flavonoids have shown promising health promoting effects in human cell culture, experimental animal and human clinical studies. They have shown antioxidant, hypocholesterolemic, anti-inflammatory effects as well as ability to modulate cell signaling and gene expression related disease development. Low bioavailability of flavonoids has been a concern as it can limit or even hinder their health effects. Therefore, attempts to improve their bioavailability in order to improve the efficacy of flavonoids are being studied. Further investigations on bioavailability are warranted as it is a determining factor for flavonoid biological activity. PMID:23989753

Modification of flavonoid biosynthesis in crop plants

NARCIS (Netherlands)

Schijlen, E.G.W.M.; Vos, de C.H.; Tunen, van A.J.; Bovy, A.G.

2004-01-01

Flavonoids comprise the most common group of polyphenolic plant secondary metabolites. In plants, flavonoids play an important role in biological processes. Beside their function as pigments in flowers and fruits, to attract pollinators and seed dispersers, flavonoids are involved in UV-scavenging,

Wine Flavonoids in Health and Disease Prevention.

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Fernandes, Iva; Pérez-Gregorio, Rosa; Soares, Susana; Mateus, Nuno; de Freitas, Victor

2017-02-14

Wine, and particularly red wine, is a beverage with a great chemical complexity that is in continuous evolution. Chemically, wine is a hydroalcoholic solution (~78% water) that comprises a wide variety of chemical components, including aldehydes, esters, ketones, lipids, minerals, organic acids, phenolics, soluble proteins, sugars and vitamins. Flavonoids constitute a major group of polyphenolic compounds which are directly associated with the organoleptic and health-promoting properties of red wine. However, due to the insufficient epidemiological and in vivo evidences on this subject, the presence of a high number of variables such as human age, metabolism, the presence of alcohol, the complex wine chemistry, and the wide array of in vivo biological effects of these compounds suggest that only cautious conclusions may be drawn from studies focusing on the direct effect of wine and any specific health issue. Nevertheless, there are several reports on the health protective properties of wine phenolics for several diseases such as cardiovascular diseases, some cancers, obesity, neurodegenerative diseases, diabetes, allergies and osteoporosis. The different interactions that wine flavonoids may have with key biological targets are crucial for some of these health-promoting effects. The interaction between some wine flavonoids and some specific enzymes are one example. The way wine flavonoids may be absorbed and metabolized could interfere with their bioavailability and therefore in their health-promoting effect. Hence, some reports have focused on flavonoids absorption, metabolism, microbiota effect and overall on flavonoids bioavailability. This review summarizes some of these major issues which are directly related to the potential health-promoting effects of wine flavonoids. Reports related to flavonoids and health highlight some relevant scientific information. However, there is still a gap between the knowledge of wine flavonoids bioavailability and their health

Wine Flavonoids in Health and Disease Prevention

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Iva Fernandes

2017-02-01

Full Text Available Wine, and particularly red wine, is a beverage with a great chemical complexity that is in continuous evolution. Chemically, wine is a hydroalcoholic solution (~78% water that comprises a wide variety of chemical components, including aldehydes, esters, ketones, lipids, minerals, organic acids, phenolics, soluble proteins, sugars and vitamins. Flavonoids constitute a major group of polyphenolic compounds which are directly associated with the organoleptic and health-promoting properties of red wine. However, due to the insufficient epidemiological and in vivo evidences on this subject, the presence of a high number of variables such as human age, metabolism, the presence of alcohol, the complex wine chemistry, and the wide array of in vivo biological effects of these compounds suggest that only cautious conclusions may be drawn from studies focusing on the direct effect of wine and any specific health issue. Nevertheless, there are several reports on the health protective properties of wine phenolics for several diseases such as cardiovascular diseases, some cancers, obesity, neurodegenerative diseases, diabetes, allergies and osteoporosis. The different interactions that wine flavonoids may have with key biological targets are crucial for some of these health-promoting effects. The interaction between some wine flavonoids and some specific enzymes are one example. The way wine flavonoids may be absorbed and metabolized could interfere with their bioavailability and therefore in their health-promoting effect. Hence, some reports have focused on flavonoids absorption, metabolism, microbiota effect and overall on flavonoids bioavailability. This review summarizes some of these major issues which are directly related to the potential health-promoting effects of wine flavonoids. Reports related to flavonoids and health highlight some relevant scientific information. However, there is still a gap between the knowledge of wine flavonoids

Cancer chemoprevention through dietary flavonoids: what's limiting?

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Amawi, Haneen; Ashby, Charles R; Tiwari, Amit K

2017-06-19

Flavonoids are polyphenols that are found in numerous edible plant species. Data obtained from preclinical and clinical studies suggest that specific flavonoids are chemo-preventive and cytotoxic against various cancers via a multitude of mechanisms. However, the clinical use of flavonoids is limited due to challenges associated with their effective use, including (1) the isolation and purification of flavonoids from their natural resources; (2) demonstration of the effects of flavonoids in reducing the risk of certain cancer, in tandem with the cost and time needed for epidemiological studies, and (3) numerous pharmacokinetic challenges (e.g., bioavailability, drug-drug interactions, and metabolic instability). Currently, numerous approaches are being used to surmount some of these challenges, thereby increasing the likelihood of flavonoids being used as chemo-preventive drugs in the clinic. In this review, we summarize the most important challenges and efforts that are being made to surmount these challenges.

Flavonoids in Kidney Health and Disease

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Félix Vargas

2018-04-01

Full Text Available This review summarizes the latest advances in knowledge on the effects of flavonoids on renal function in health and disease. Flavonoids have antihypertensive, antidiabetic, and antiinflammatory effects, among other therapeutic activities. Many of them also exert renoprotective actions that may be of interest in diseases such as glomerulonephritis, diabetic nephropathy, and chemically-induced kidney insufficiency. They affect several renal factors that promote diuresis and natriuresis, which may contribute to their well-known antihypertensive effect. Flavonoids prevent or attenuate the renal injury associated with arterial hypertension, both by decreasing blood pressure and by acting directly on the renal parenchyma. These outcomes derive from their interference with multiple signaling pathways known to produce renal injury and are independent of their blood pressure-lowering effects. Oral administration of flavonoids prevents or ameliorates adverse effects on the kidney of elevated fructose consumption, high fat diet, and types I and 2 diabetes. These compounds attenuate the hyperglycemia-disrupted renal endothelial barrier function, urinary microalbumin excretion, and glomerular hyperfiltration that results from a reduction of podocyte injury, a determinant factor for albuminuria in diabetic nephropathy. Several flavonoids have shown renal protective effects against many nephrotoxic agents that frequently cause acute kidney injury (AKI or chronic kidney disease (CKD, such as LPS, gentamycin, alcohol, nicotine, lead or cadmium. Flavonoids also improve cisplatin- or methotrexate-induced renal damage, demonstrating important actions in chemotherapy, anticancer and renoprotective effects. A beneficial prophylactic effect of flavonoids has been also observed against AKI induced by surgical procedures such as ischemia/reperfusion (I/R or cardiopulmonary bypass. In several murine models of CKD, impaired kidney function was significantly improved by

Antioxidant flavonoids bind human serum albumin

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Kanakis, C. D.; Tarantilis, P. A.; Polissiou, M. G.; Diamantoglou, S.; Tajmir-Riahi, H. A.

2006-10-01

Human serum albumin (HSA) is a principal extracellular protein with a high concentration in blood plasma and carrier for many drugs to different molecular targets. Flavonoids are powerful antioxidants and prevent DNA damage. The antioxidative protections are related to their binding modes to DNA duplex and complexation with free radicals in vivo. However, flavonoids are known to inhibit the activities of several enzymes such as calcium phospholipid-dependent protein kinase, tyrosine protein kinase from rat lung, phosphorylase kinase, phosphatidylinositol 3-kinase and DNA topoisomerases that exhibit the importance of flavonoid-protein interaction. This study was designed to examine the interaction of human serum albumin (HSA) with quercetin (que), kaempferol (kae) and delphinidin (del) in aqueous solution at physiological conditions, using constant protein concentration of 0.25 mM (final) and various drug contents of 1 μM-1 mM. FTIR and UV-vis spectroscopic methods were used to determine the polyphenolic binding mode, the binding constant and the effects of flavonoid complexation on protein secondary structure. The spectroscopic results showed that flavonoids are located along the polypeptide chains through H-bonding interactions with overall affinity constant of Kque = 1.4 × 10 4 M -1, Kkae = 2.6 × 10 5 M -1 and Kdel = 4.71 × 10 5 M -1. The protein secondary structure showed no alterations at low pigment concentration (1 μM), whereas at high flavonoid content (1 mM), major reduction of α-helix from 55% (free HSA) to 42-46% and increase of β-sheet from 15% (free HSA) to 17-19% and β-anti from 7% (free HSA) to 10-20% occurred in the flavonoid-HSA adducts. The major reduction of HSA α-helix is indicative of a partial protein unfolding upon flavonoid interaction.

Flavonoid-surfactant interactions: A detailed physicochemical study

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Singh, Onkar; Kaur, Rajwinder; Mahajan, Rakesh Kumar

2017-01-01

The aim of this article is to study the interactions between flavonoids and surfactants with attention of finding the probable location of flavonoids in micellar media that can be used for controlling their antioxidant behavior. In present study, the micellar and interfacial behavior of twin tailed anionic surfactants viz. sodium bis(2-ethylhexyl)sulfosuccinate (AOT) and sodium bis(2-ethylhexyl)phosphate (NaDEHP) in the presence of two flavonoids, namely quercetin (QUE) and kaempferol (KFL) have been studied by surface tension measurements. UV-visible, fluorescence and differential pulse voltammetric (DPV) measurements have been employed to predict the probable location of flavonoids (QUE/KFL) within surfactant (AOT/NaDEHP) aggregates. Dynamic light scattering (DLS) measurements further confirmed the solubilization of QUE/KFL in AOT/NaDEHP aggregates deduced from increased hydrodynamic diameter (Dh) of aggregates in the presence of flavonoids. Both radical scavenging activity (RSA) and degradation rate constant (k) of flavonoids are found to be higher in NaDEHP micelles as compared to AOT micelles.

Flavonoids and heart health: Proceedings of the ILSI North America Flavonoids Workshop may 31-june 1, 2005, Washington DC

NARCIS (Netherlands)

Erdman, J.W.; Balentine, D.; Arab, L.; Beecher, G.; Dwyer, J.T.; Folts, J.; Harnly, J.; Hollman, P.C.H.; Keen, C.L.; Mazza, G.; Messina, M.; Scalbert, A.; Vita, J.; Williamson, G.; Burrows, J.

2007-01-01

This article provides an overview of current research on flavonoids as presented during a workshop entitled, "Flavonoids and Heart Health," held by the ILSI North America Project Committee on Flavonoids in Washington, DC, May 31 and June 1, 2005. Because a thorough knowledge and understanding about

Subsidiary Linkage Patterns

DEFF Research Database (Denmark)

Andersson, Ulf; Perri, Alessandra; Nell, Phillip C.

2012-01-01

channels for spillovers to competitors. We find a curvilinear relationship between the extent of competitive pressure and the quality of a subsidiary's set of local linkages. Furthermore, the extent to which a subsidiary possesses capabilities moderates this relationship: Very capable subsidiaries...... in strongly competitive environments tend to shy away from high quality linkages. We discuss our findings in light of the literature on spillovers and inter-organizational linkages.......This paper investigates the pattern of subsidiaries' local vertical linkages under varying levels of competition and subsidiary capabilities. Contrary to most previous literature, we explicitly account for the double role of such linkages as conduits of learning prospects as well as potential...

Impact of certain flavonoids on lipid profiles--potential action of Garcinia cambogia flavonoids.

Science.gov (United States)

Koshy, A S; Vijayalakshmi, N R

2001-08-01

Flavonoids from Cocos nucifera, Myristica fragrance, Saraka asoka and Garcinia cambogia exerted hypolipidaemic activity in rats. Lipid lowering activity was maximum in rats administered flavonoids (10 mg/kg BW/day) from Garcinia cambogia. A dose response study revealed biphasic activity. Higher doses were less effective in reducing lipid levels in serum and tissues, although devoid of toxic effects. Copyright 2001 John Wiley & Sons, Ltd.

Flavonoids, flavonoid-rich foods, and cardiovascular risk: a meta-analysis of randomized controlled trials.

Science.gov (United States)

Hooper, Lee; Kroon, Paul A; Rimm, Eric B; Cohn, Jeffrey S; Harvey, Ian; Le Cornu, Kathryn A; Ryder, Jonathan J; Hall, Wendy L; Cassidy, Aedín

2008-07-01

The beneficial effects of flavonoid consumption on cardiovascular risk are supported by mechanistic and epidemiologic evidence. We aimed to systematically review the effectiveness of different flavonoid subclasses and flavonoid-rich food sources on cardiovascular disease (CVD) and risk factors--ie, lipoproteins, blood pressure, and flow-mediated dilatation (FMD). Methods included a structured search strategy on MEDLINE, EMBASE, and Cochrane databases; formal inclusion or exclusion, data extraction, and validity assessment; and meta-analysis. One hundred thirty-three trials were included. No randomized controlled trial studied effects on CVD morbidity or mortality. Significant heterogeneity confirmed differential effects between flavonoid subclasses and foods. Chocolate increased FMD after acute (3.99%; 95% CI: 2.86, 5.12; 6 studies) and chronic (1.45%; 0.62, 2.28; 2 studies) intake and reduced systolic (-5.88 mm Hg; -9.55, -2.21; 5 studies) and diastolic (-3.30 mm Hg; -5.77, -0.83; 4 studies) blood pressure. Soy protein isolate (but not other soy products or components) significantly reduced diastolic blood pressure (-1.99 mm Hg; -2.86, -1.12; 9 studies) and LDL cholesterol (-0.19 mmol/L; -0.24, -0.14; 39 studies). Acute black tea consumption increased systolic (5.69 mm Hg; 1.52, 9.86; 4 studies) and diastolic (2.56 mm Hg; 1.03, 4.10; 4 studies) blood pressure. Green tea reduced LDL (-0.23 mmol/L; -0.34, -0.12; 4 studies). For many of the other flavonoids, there was insufficient evidence to draw conclusions about efficacy. To date, the effects of flavonoids from soy and cocoa have been the main focus of attention. Future studies should focus on other commonly consumed subclasses (eg, anthocyanins and flavanones), examine dose-response effects, and be of long enough duration to allow assessment of clinically relevant endpoints.

Potential ecological roles of flavonoids from Stellera chamaejasme.

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Yan, Zhiqiang; Zeng, Liming; Jin, Hui; Qin, Bo

2015-01-01

Stellera chamaejasme L. (Thymelaeaceae), a perennial weed, distributes widely in the grasslands of Russia, Mongolia and China. The plant synthesizes various secondary metabolites including a group of flavonoids. To our knowledge, flavonoids play important roles in the interactions between plants and the environment. So, what are the benefits to S. chamaejasme from producing these flavonoids? Here, we discuss the potential ecological role of flavonoids from S. chamaejasme in protecting the plant from insects and other herbivores, as well as pathogens and competing plant species, and new data are provided on the phytotoxicity of flavonoids from S. chamaejasme toward Poa annua L.

Flavonoids: promising natural compounds against viral infections.

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Zakaryan, Hovakim; Arabyan, Erik; Oo, Adrian; Zandi, Keivan

2017-09-01

Flavonoids are widely distributed as secondary metabolites produced by plants and play important roles in plant physiology, having a variety of potential biological benefits such as antioxidant, anti-inflammatory, anticancer, antibacterial, antifungal and antiviral activity. Different flavonoids have been investigated for their potential antiviral activities and several of them exhibited significant antiviral properties in in vitro and even in vivo studies. This review summarizes the evidence for antiviral activity of different flavonoids, highlighting, where investigated, the cellular and molecular mechanisms of action on viruses. We also present future perspectives on therapeutic applications of flavonoids against viral infections.

Marine natural flavonoids: chemistry and biological activities.

Science.gov (United States)

Martins, Beatriz T; Correia da Silva, Marta; Pinto, Madalena; Cidade, Honorina; Kijjoa, Anake

2018-05-04

As more than 70% of the world's surface is covered by oceans, marine organisms offer a rich and unlimited resource of structurally diverse bioactive compounds. These organisms have developed unique properties and bioactive compounds that are, in majority of them, unparalleled by their terrestrial counterparts due to the different surrounding ecological systems. Marine flavonoids have been extensively studied in the last decades due to a growing interest concerning their promising biological/pharmacological activities. The most common classes of marine flavonoids are flavones and flavonols, which are mostly isolated from marine plants. Although most of flavonoids are hydroxylated and methoxylated, some marine flavonoids possess an unusual substitution pattern, not commonly found in terrestrial organisms, namely the presence of sulphate, chlorine, and amino groups. This review presents, for the first time in a systematic way, the structure, natural occurrence, and biological activities of marine flavonoids.

Natural Flavonoids as Promising Analgesic Candidates: A Systematic Review.

Science.gov (United States)

Xiao, Xiao; Wang, Xiaoyu; Gui, Xuan; Chen, Lu; Huang, Baokang

2016-11-01

Due to the chemical structural diversity and various analgesic mechanisms, an increasing number of studies indicated that some flavonoids from medicinal plants could be promising candidates for new natural analgesic drugs, which attract high interests of advanced users and academic researchers. The aim of this systematic review is to report flavonoids and its derivatives as new analgesic candidates based on the pharmacological evidences. Sixty-four papers were found concerning the potential analgesic activity of 46 flavonoids. In this case, the evidence for analgesic activity of flavonoids and total flavonoids was investigated. Meanwhile, the corresponding analgesic mechanism of flavonoids was discussed by generalizing and analyzing the current publications. Based on this review, the conclusion can be drawn that some flavonoids are promising candidates for painful conditions and deserve particular attention in further research and development. © 2016 Wiley-VHCA AG, Zurich, Switzerland.

Metode Cepat Identifikasi Flavonoid dari Daun Ocimum sanctum L. (Selasih

Directory of Open Access Journals (Sweden)

Diah Dhianawaty

2012-03-01

Full Text Available A plant’s effectiveness as a herbal drug comes from its chemical content such as flavonoids. Flavonoids are useful for human body health. Therefore flavonoids content can be used as a marker from the usefulness of a plant, and rapid identification method of flavonoid is needed. The objective of the research was to get a rapid method of flavonoid content identification from Ocimum sanctum. The extraction, isolation and identification of flavonoids from Ocimum sanctum leaves has been done at Medical Chemistry laboratory Faculty of Medicine Universitas Padjadjaran in 2005. Flavonoids were extracted continually by 95% ethanol, were isolated with paper chromatography/cellulose TLC and 2% acetic acid, then continued with elucidation reagents: n-butanol–acetic acid–water, chloroform–acetic acid–water, forestall, 5%, 15%, 35% and 50% acetic acids. Flavonoids were identified with diagnostic reagents and ultraviolet light. Isolation with 2% and 35% acetic acids respectively gave two spots of flavonoids as flavon, FOAc-1 had Rf=0.69 and FOAc-2 had Rf=0.57. The other elucidation reagents gave one spot of flavonoid. In conclusion, isolation with 2% and 35% acetic acids respectively and identification with diagnostic reagent and ultraviolet light is a rapid method for identification of flavonoids content in Ocimum sanctum

Citrus Flavonoids as Regulators of Lipoprotein Metabolism and Atherosclerosis.

Science.gov (United States)

Mulvihill, Erin E; Burke, Amy C; Huff, Murray W

2016-07-17

Citrus flavonoids are polyphenolic compounds with significant biological properties. This review summarizes recent advances in understanding the ability of citrus flavonoids to modulate lipid metabolism, other metabolic parameters related to the metabolic syndrome, and atherosclerosis. Citrus flavonoids, including naringenin, hesperitin, nobiletin, and tangeretin, have emerged as potential therapeutics for the treatment of metabolic dysregulation. Epidemiological studies reveal an association between the intake of citrus flavonoid-containing foods and a decreased incidence of cardiovascular disease. Studies in cell culture and animal models, as well as a limited number of clinical studies, reveal the lipid-lowering, insulin-sensitizing, antihypertensive, and anti-inflammatory properties of citrus flavonoids. In animal models, supplementation of rodent diets with citrus flavonoids prevents hepatic steatosis, dyslipidemia, and insulin resistance primarily through inhibition of hepatic fatty acid synthesis and increased fatty acid oxidation. Citrus flavonoids blunt the inflammatory response in metabolically important tissues including liver, adipose, kidney, and the aorta. The mechanisms underlying flavonoid-induced metabolic regulation have not been completely established, although several potential targets have been identified. In mouse models, citrus flavonoids show marked suppression of atherogenesis through improved metabolic parameters as well as through direct impact on the vessel wall. Recent studies support a role for citrus flavonoids in the treatment of dyslipidemia, insulin resistance, hepatic steatosis, obesity, and atherosclerosis. Larger human studies examining dose, bioavailability, efficacy, and safety are required to promote the development of these promising therapeutic agents.

Flavonoids as fruit and vegetable intake biomarkers

DEFF Research Database (Denmark)

Krogholm, Kirstine Suszkiewicz

of fruit and vegetable intakes. In Paper I, the urinary recovery of the 7 flavonoids in morning spot urine (i.e. all urine voids from midnight including the first morning void) was also found to respond to moderate increases in the intake of fruits and vegetables. However, the association was somewhat...... weaker than in 24h urine samples, indicating that the 24h urinary recovery of the 7 flavonoids is a stronger biomarker of the intake of fruit and vegetables than the urinary recovery of the 7 flavonoids in morning spot urine. In Paper II, the biokinetic profiles of some of the most important dietary......-individual variation in the absorption and urinary recovery of the flavonoids, and this makes it very difficult to separate individuals according to intake by use of the flavonoid biomarker in urine. The intra-individual variation was on the contrary low, and Paper II therefore supports the assumption, that 24h...

Structure-cytotoxicity relationships for dietary flavonoids

DEFF Research Database (Denmark)

Breinholt, V.; Dragsted, L.O.

1998-01-01

The cytotoxicity of a large series of dietary flavonoids was tested in a non-tumorigenic mouse and two human cancer cell lines, using the neutral red dye exclusion assay. All compounds tested exhibited a concentration-dependent cytotoxic action in the employed cell lines. The relative cytotoxicity...... of the flavonoids, however, Tvas found to vary greatly among the different cell Lines. With a few exceptions, the investigated flavonoids were more cytotoxic to the human cancer cell lines, than the mouse cell line. The differences in cytotoxicity were accounted for in part by differences in cellular uptake...... and metabolic capacity among the different cell types. In 3T3 cells fairly consistent structure-cytotoxicity relationships were found. The most cytotoxic structures tested in 3T3 cells were flavonoids with adjacent 3',4' hydroxy groups on the B-ring, such as luteolin, quercetin, myricetin, fisetin, eriodictyol...

Cytoprotective effects of dietary flavonoids against cadmium-induced toxicity.

Science.gov (United States)

Li, Xia; Jiang, Xinwei; Sun, Jianxia; Zhu, Cuijuan; Li, Xiaoling; Tian, Lingmin; Liu, Liu; Bai, Weibin

2017-06-01

Cadmium (Cd) damages the liver, kidney, bones, reproductive system, and other organs. Flavonoids, such as anthocyanins and flavonols, which are commonly found in plant foods, have shown protective effects against Cd-induced damage. The cytoprotective effects of flavonoids against Cd-induced diseases are mainly attributable to three mechanisms. First, flavonoids clear reactive oxygen species, thereby reducing lipid peroxide production and improving the activity of antioxidation enzymes. Second, flavonoids chelate Cd, thus reducing the accumulation of Cd and altering the levels of other essential metal ions in vivo. Third, flavonoids reduce DNA damage and inhibit apoptosis. In addition, flavonoids were found to inhibit inflammation and fibrosis and improve glycometabolism and the secretion of reproductive hormones. We introduce the daily dosage and absorption rate of flavonoids and then focus on their bioactive effects against Cd-induced toxicity and reveal the underlying metabolic pathway, which provides a basis for further study of the nutritional prevention of Cd-induced injury. In particular, a better understanding is needed of the structure-activity relationship of flavonoids against Cd toxicity, which has not yet been reported. © 2017 New York Academy of Sciences.

Antimicrobial action of purified raspberry flavonoid

African Journals Online (AJOL)

user

2012-02-07

Feb 7, 2012 ... numerous research groups have sought to elucidate the antibacterial mechanisms of action of selected flavonoids. *Corresponding author. E-mail: bdsunjinxu@163.com. (Cushnie et al., 2005), but there have been no reports on the bacteriostatic and bactericidal action of raspberry flavonoid. In this paper ...

Inhibition of transmembrane member 16A calcium-activated chloride channels by natural flavonoids contributes to flavonoid anticancer effects.

Science.gov (United States)

Zhang, Xuan; Li, Honglin; Zhang, Huiran; Liu, Yani; Huo, Lifang; Jia, Zhanfeng; Xue, Yucong; Sun, Xiaorun; Zhang, Wei

2017-07-01

Natural flavonoids are ubiquitous in dietary plants and vegetables and have been proposed to have antiviral, antioxidant, cardiovascular protective and anticancer effects. Transmembrane member 16A (TMEM16A)-encoded Ca 2+ -activated Cl - channels play a variety of physiological roles in many organs and tissues. Overexpression of TMEM16A is also believed to be associated with cancer progression. Therefore, inhibition of TMEM16A current may be a potential target for cancer therapy. In this study, we screened a broad spectrum of flavonoids for their inhibitory activities on TMEM16A currents. A whole-cell patch technique was used to record the currents. The BrdU assay and transwell technique were used to investigate cell proliferation and migration. At a concentration of 100 μM, 10 of 20 compounds caused significant (>50%) inhibition of TMEM16A currents. The four most potent compounds - luteolin, galangin, quercetin and fisetin - had IC 50 values ranging from 4.5 to 15 μM). To examine the physiological relevance of these findings, we also studied the effects of these flavonoids on endogenous TMEM16A currents in addition to cell proliferation and migration in LA795 cancer cells. Among the flavonoids tested, we detected a highly significant correlation between TMEM16A current inhibition and cell proliferation or reduction of migration. This study demonstrates that flavonoids inhibit TMEM16A currents and suggests that flavonoids could have anticancer effects via this mechanism. © 2017 The British Pharmacological Society.

Bioavailability, metabolism and potential health protective effects of dietary flavonoids

DEFF Research Database (Denmark)

Bredsdorff, Lea

Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several...... epidemiological studies but the evidence is inconclusive. One major obstacle for epidemiological studies investigating associations between flavonoid intake and risk of CHD is the estimation of flavonoid intake. There is a vast variety of flavonoids in commonly eaten food products but only limited knowledge...... of their content. In addition, variation in individual metabolic genotype and microflora may greatly affect the actual flavonoid exposure. The preventive effects of flavonoids on CHD are mainly ascribed to their anti-inflammatory and antioxidant activities. Several mechanisms of anti-inflammatory and antioxidant...

Flavonoids from Teucrium fruticans L.

Directory of Open Access Journals (Sweden)

Wanda Kisiel

2014-01-01

Full Text Available From aerial parts of Teucrium fncticans L. three flavonoids were isolated and identified as 5-hydroxy-6, 7, 3', 4'-tetramethoxyflavone, 5, 4'-dihydroxy-6, 7, 3'-trimethoxyflavone (cirsilineol and 5, 4'-dihydroxy-6, 7-dimethoxyflavone (cirsimaritin. The former compound was found to be a predominant flavone aglycone constituent of the plant material. This is the first report on the isolation of flavonoids from the plant.

The biochemistry and medical significance of the flavonoids.

Science.gov (United States)

Havsteen, Bent H

2002-01-01

Flavonoids are plant pigments that are synthesised from phenylalanine, generally display marvelous colors known from flower petals, mostly emit brilliant fluorescence when they are excited by UV light, and are ubiquitous to green plant cells. The flavonoids are used by botanists for taxonomical classification. They regulate plant growth by inhibition of the exocytosis of the auxin indolyl acetic acid, as well as by induction of gene expression, and they influence other biological cells in numerous ways. Flavonoids inhibit or kill many bacterial strains, inhibit important viral enzymes, such as reverse transcriptase and protease, and destroy some pathogenic protozoans. Yet, their toxicity to animal cells is low. Flavonoids are major functional components of many herbal and insect preparations for medical use, e.g., propolis (bee's glue) and honey, which have been used since ancient times. The daily intake of flavonoids with normal food, especially fruit and vegetables, is 1-2 g. Modern authorised physicians are increasing their use of pure flavonoids to treat many important common diseases, due to their proven ability to inhibit specific enzymes, to simulate some hormones and neurotransmitters, and to scavenge free radicals.

Purification of Flavonoids from Black Currant Juice by Nanodiafiltration

DEFF Research Database (Denmark)

Jensen, Morten Busch; Christensen, Knud Villy; Norddahl, Birgir

2009-01-01

  Various compounds of the flavonoid group have been reported to possess therapeutic effects towards cancer [1]. Thus there is a large potential in identifying, purifying and quantifying flavonoids from different natural sources in order to screen the pharmaceutical values of these. The flavonoid...

Genetic diversity of flavonoid content in leaf of hawthorn resources

International Nuclear Information System (INIS)

Zhao, Y.; Wang, G.; Liu, Z.

2014-01-01

Hawthorn (Cratageus spp.) are important medicinal plants. Flavonoids are the main active ingredient in hawthorn. With the help of hawthorn leaf flavonoids efficient detection system, vitexin, rhamnosylvitexin, hyperin, rutin and quercetin of 122 hawthorn resources was precisely measured.The flavonoid contents of 10 hawthorn species were explicited. The comparation of flavonoids revealed the abundant genetic diversity of hawthorn flavones. Large variable coefficient has been observed among 5 flavonoid monomer traits. The coefficients of variation were 44.17%, 132.2%, 157.08%, 113.91% and 31.05 for Vitexin, Rhamnosylvitexin, Hyperoside, Rutin and Quercetin respectively. The sum of these 5 flavonoid monomer contents represented the total flavonoids in hawthorn. The total coefficients of variation was 44.01%. Some high-content-flavone and valuable leaf resources were found. This research could provide accurate date for further production, breeding and the effective use of medicinal resources. (author)

Flavonoids as modulators of metabolic enzymes and drug transporters.

Science.gov (United States)

Miron, Anca; Aprotosoaie, Ana Clara; Trifan, Adriana; Xiao, Jianbo

2017-06-01

Flavonoids, natural compounds found in plants and in plant-derived foods and beverages, have been extensively studied with regard to their capacity to modulate metabolic enzymes and drug transporters. In vitro, flavonoids predominantly inhibit the major phase I drug-metabolizing enzyme CYP450 3A4 and the enzymes responsible for the bioactivation of procarcinogens (CYP1 enzymes) and upregulate the enzymes involved in carcinogen detoxification (UDP-glucuronosyltransferases, glutathione S-transferases (GSTs)). Flavonoids have been reported to inhibit ATP-binding cassette (ABC) transporters (multidrug resistance (MDR)-associated proteins, breast cancer-resistance protein) that contribute to the development of MDR. P-glycoprotein, an ABC transporter that limits drug bioavailability and also induces MDR, was differently modulated by flavonoids. Flavonoids and their phase II metabolites (sulfates, glucuronides) inhibit organic anion transporters involved in the tubular uptake of nephrotoxic compounds. In vivo studies have partially confirmed in vitro findings, suggesting that the mechanisms underlying the modulatory effects of flavonoids are complex and difficult to predict in vivo. Data summarized in this review strongly support the view that flavonoids are promising candidates for the enhancement of oral drug bioavailability, chemoprevention, and reversal of MDR. © 2017 New York Academy of Sciences.

Flavonoids of Calligonum polygonoides and their cytotoxicity.

Science.gov (United States)

Ahmed, Hayam; Moawad, Abeer; Owis, Asmaa; AbouZid, Sameh; Ahmed, Osama

2016-10-01

Context Calligonum polygonoides L. subsp. comosum L' Hér. (Polygonaceae), locally known as "arta", is a slow-growing small leafless desert shrub. Objective Isolation, structure elucidation and evaluation of cytotoxic activity of flavonoids from C. polygonoides aerial parts. Materials and methods Flavonoids in the hydroalcoholic extract of the of C. polygonoides were isolated and purified using column chromatography and preparative HPLC. The structures of the isolated flavonoids were elucidated on the basis of spectroscopic data including 2D NMR techniques. The cytotoxic activity of the isolated flavonoids (6.25, 25, 50 and 100 μg/mL) was evaluated against liver HepG2 and breast MCF-7 cancer cell lines using sulphorhodamine-B assay. Results A new flavonoid, kaempferol-3-O-β-D-(6″-n-butyl glucuronide) (1), and 13 known flavonoids, quercetin 3-O-β-D-(6″-n-butyl glucuronide) (2), kaempferol-3-O-β-D-(6″-methyl glucuronide) (3), quercetin-3-O-β-D-(6″-methyl glucuronide) (4), quercetin-3-O-glucuronide (5), kaempferol-3-O-glucuronide (6), quercetin-3-O-α-rhamnopyranoside (7), astragalin (8), quercetin-3-O-glucopyranoside (9), taxifolin (10), (+)-catechin (11), dehydrodicatechin A (12), quercetin (13), and kaempferol (14), were isolated from the aerial parts of C. polygonoides. Quercetin showed significant cytotoxic activity against HepG2 and MCF-7 cell lines with IC50 values of 4.88 and 0.87 μg/mL, respectively. Structure-activity relationships were analyzed by comparing IC50 values of several pairs of flavonoids differing in one structural element. Discussion and conclusion The activity against breast cancer cell lines decreased by glycosylation at C-3. The presence of 2,3-double bond in ring C, carbonyl group at C-4 and 3',4'-dihydroxy substituents in ring B are essential structural requirements for the cytotoxic activity against breast cancer cells.

Floral flavonoids and ultraviolet patterns in Viguiera (Compositae)

International Nuclear Information System (INIS)

Rieseberg, L.H.; Schilling, E.E.

1985-01-01

Variation occurs among species of Viguiera series Viguiera for ultraviolet (UV) absorption/reflection patterns of ligules. Floral flavonoids that cause UV absorption occur in epidermal papillae. Flavonoids are further localized to the proximal portion of the ligule in the seven taxa that have only proximal UV absorption. Floral flavonoids involved in UV absorption consist of flavone, flavonol, and anthochlor (chalcone/aurone) glycosides. Quercetin 3-methyl ether glycosides characterize the ligules of 10 taxa occurring in Baja California, Mexico, and nearby areas, and these taxa appear to form one taxonomic group. The anthochlor pair, marein/maritimein, characterizes V. dentata, and the lack of ligule flavonoids distinguishes V. potosina from the remaining taxa. The presence of the anthochlor pair, marein/maritimein, only in V. dentata and the lack of ligule flavonoids in V. potosina concur with other data to indicate that these species are not correctly placed with each other or with the other species currently included in series Viguiera. (author)

Flavonoid variation in Eurasian Sedum and Sempervivum

NARCIS (Netherlands)

Stevens, J.F; 't Hart, H; Elema, E.T; Bolck, A

Flavonoids from vegetative parts of 29 species of Eurasian Sedum, Sedum meyeri-johannis from central East Africa, 34 species of Sempervivum, and Jovibarba heuffelii have been identified after acid hydrolysis. Ten flavonoid aglycones were detected, i.e. kaempferol, herbacetin, sexangularetin,

Isolation and identification of flavonoids, including flavone rotamers, from the herbal drug 'Crataegi folium cum flore' (hawthorn).

Science.gov (United States)

Rayyan, S; Fossen, T; Solheim Nateland, H; Andersen, O M

2005-01-01

Twelve flavonoids, including seven flavones, four flavonols and one flavanone, were isolated from methanolic extract of the herbal drug 'Crataegi folium cum flore' (hawthorn leaves and flowers) by a combination of CC (over Amberlite XAD-7 and Sephadex LH-20) and preparative HPLC. Their structures, including that of the novel flavonol 8-methoxykaempferol 3-O-(6"-malonyl-beta-glucopyranoside), were elucidated by homo- and heteronuclear NMR and electrospray/MS. The 1H- and 13C-NMR of all compounds, including rotameric pairs of five flavone C-glycosides, were assigned. The presence and relative proportion of each rotamer was shown by various NMR experiments, including two-dimensional nuclear Overhauser and exchange spectroscopy, to depend on solvent, linkage position and structure of the C-glycosyl substituent.

Dietary supplementation with mulberry leaf flavonoids inhibits methanogenesis in sheep.

Science.gov (United States)

Ma, Tao; Chen, Dan-Dan; Tu, Yan; Zhang, Nai-Feng; Si, Bing-Wen; Diao, Qi-Yu

2017-01-01

The effects of flavonoids on methanogenesis and microbial flora in Dorper × thin-tailed Han crossbred ewes were evaluated in two experiments. To investigate the effects of flavonoids on nutrient digestibility and nitrogen balance, 18 ewes (60.0 ± 1.73 kg body weight (BW)) were allotted to two dietary treatments in experiment one, a control diet and the control diet supplemented with flavonoids (2 g/head/day). In experiment two, the effects of supplementary flavonoids on ruminal fermentation and microbial flora were investigated using quantitative polymerase chain reaction with six ewes (67.2 ± 0.79 kg BW) with ruminal cannula assigned to the identical dietary treatments used in experiment one. Supplementary flavonoids improved the apparent digestibility of nitrogen (N, P flavonoids, whereas the total volatile fatty acid (VFA) content increased (P = 0.037). Supplementary flavonoids decreased ruminal populations of protozoans (P = 0.002) and methanogens (P flavonoids improved the digestibility of organic matter and reduced CH 4 output by inhibiting the populations of microbes involved in methanogenesis. © 2016 Japanese Society of Animal Science.

Flavonoids as fruit and vegetable intake biomarkers

DEFF Research Database (Denmark)

Krogholm, Kirstine Suszkiewicz

calculation of the bivariate correlation coefficients is the common approach when using only one reference method. Back in 2002, a strictly controlled dietary intervention study indicated that the sum of 7 different flavonoid aglycones excreted in 24h urine samples potentially could be used as a biomarker...... and cohort studies. The Ph.D. thesis contains four scientific papers. Paper I provides evidence that the sum of 7 flavonoids in 24h urine respond in a linear and sensitive manner to moderate increases in the intake of fruits and vegetables, and thus consolidates that the flavonoids are a valid biomarker...... of fruit and vegetable intakes. In Paper I, the urinary recovery of the 7 flavonoids in morning spot urine (i.e. all urine voids from midnight including the first morning void) was also found to respond to moderate increases in the intake of fruits and vegetables. However, the association was somewhat...

Influence of Intestinal Microbiota on the Catabolism of Flavonoids in Mice.

Science.gov (United States)

Lin, Weiqun; Wang, Wenting; Yang, Hai; Wang, Dongliang; Ling, Wenhua

2016-12-01

Although in vitro studies have shown that flavonoids are metabolized into phenolic acids by the gut microbiota, the biotransformation of flavonoids by intestinal microbiota is seldom studied in vivo. In this study, we investigated the impact of the gut microbiota on the biotransformation of 3 subclasses of flavonoids (flavonols, flavones, and flavanones). The ability of intestinal microbiota to convert flavonoids was confirmed with an in vitro fermentation model using mouse gut microflora. Simultaneously, purified flavonoids were administered to control and antibiotic-treated mice by gavage, and the metabolism of these flavonoids was evaluated. p-Hydroxyphenylacetic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, hydrocaffeic acid, coumaric acid, and 3-(4-hydroxyphenyl)propionic acid were detected in the serum samples from the control mice after flavonoid consumption. The serum flavonoid concentrations were similar in both groups, whereas the phenolic metabolite concentrations were lower in the antibiotic-treated mice than in the control mice. We detected markedly higher flavonoids excretion in the feces and urine of the antibiotic-treated mice compared to the controls. Moreover, phenolic metabolites were upregulated in the control mice. These results suggest that the intestinal microbiota are not necessary for the absorption of flavonoids, but are required for their transformation. © 2016 Institute of Food Technologists®.

A pantograph linkage

International Nuclear Information System (INIS)

Cole, G.V.

1982-01-01

A pantograph linkage is actuated by two linear actuators, pivotally connected together at the linkage. The displacement of the actuators is monitored by rectilinear potentiometers to provide feedback signals to a microprocessor which also receives input signals related to a required movement of a slave end of the linkage. In response to these signals, the microprocessor provides signals to control the displacement of the linear actuators to effect the required movement of the slave end. The movement of the slave end might be straightline in a substantially horizontal or vertical direction. (author)

Flavonoid accumulation patterns of transparent testa mutants of arabidopsis

Science.gov (United States)

Peer, W. A.; Brown, D. E.; Tague, B. W.; Muday, G. K.; Taiz, L.; Murphy, A. S.

2001-01-01

Flavonoids have been implicated in the regulation of auxin movements in Arabidopsis. To understand when and where flavonoids may be acting to control auxin movement, the flavonoid accumulation pattern was examined in young seedlings and mature tissues of wild-type Arabidopsis. Using a variety of biochemical and visualization techniques, flavonoid accumulation in mature plants was localized in cauline leaves, pollen, stigmata, and floral primordia, and in the stems of young, actively growing inflorescences. In young Landsberg erecta seedlings, aglycone flavonols accumulated developmentally in three regions, the cotyledonary node, the hypocotyl-root transition zone, and the root tip. Aglycone flavonols accumulated at the hypocotyl-root transition zone in a developmental and tissue-specific manner with kaempferol in the epidermis and quercetin in the cortex. Quercetin localized subcellularly in the nuclear region, plasma membrane, and endomembrane system, whereas kaempferol localized in the nuclear region and plasma membrane. The flavonoid accumulation pattern was also examined in transparent testa mutants blocked at different steps in the flavonoid biosynthesis pathway. The transparent testa mutants were shown to have precursor accumulation patterns similar to those of end product flavonoids in wild-type Landsberg erecta, suggesting that synthesis and end product accumulation occur in the same cells.

UV radiation dependent flavonoid accumulation of Cistus laurifolius L

International Nuclear Information System (INIS)

Vogt, T.; Gülz, P.-G.; Reznik, H.

1991-01-01

Epicuticular and intracellular flavonoids of Cistus laurifolius grown with and without UV radiation in a phytotron as well as under natural garden conditions in the field were studied. The amount of intracellular flavonoid glycosides of leaves receiving UV-A radiation was two fold higher than that measured in the absence o f UV-A radiation, whether grown in the phytotron or in the field. Exposure of previously protected leaves to UV-A radiation increased the intracellular flavonoid glycoside content to that of unprotected leaves. The qualitative composition of intracellular flavonoid glycosides showed a reduced amount of quercetin-3-galactoside to the myricetin monosides when the leaves were grown without UV-A radiation in the field and in the phytotron. Epicuticular flavonoid aglycones were not influenced by UV radiation significantly. (author)

Aktivitas antibakteri flavonoid propolis Trigona sp terhadap bakteri Streptococcus mutans (in vitro (In vitro antibacterial activity of flavonoids Trigona sp propolis against Streptococcus mutans

Directory of Open Access Journals (Sweden)

Ardo Sabir

2005-09-01

Full Text Available A number of investigations have shown a positive correlation between the number of Streptococcus mutans (S. mutans in dental plaque and the prevalence of dental caries. Consequently, this microorganism has been the prime target for the prevention of dental caries. Propolis being a substance made by the honeybee, is a potent antibacterial agent. The main chemical class present in propolis is flavonoids. Flavonoids are well-known plant compounds that have antibacterial property. Because S. mutans is accepted to be one of the microorganisms responsible for dental caries and flavonoids in propolis are antibacterial, the purpose of this study was to evaluate in vitro the antibacterial activity of flavonoids Trigona sp propolis against S. mutans as a first step in its possible use as an alternative anticaries agent. Extract flavonoids was purified from ethanol extract of propolis which was obtained from Bulukumba Regency South Sulawesi using thin layer chromatography. The purification of flavonoids was carried-out by UVradiation at λ max 254 nm and λmax 366 nm and treatment with ammonia. Extract flavonoids was diluted in aquadest to 0.05%; 0.075%; 0.1%; 0.25%; 0.5%; 0.75% concentrations. Aquadest and 10% Povidone iodine were also used as control solution. S mutans were grown in medium glucose nutrient agar and incubated with flavonoids for 24 and 48 hours, at 37° C. Antibacterial activity was reflected by the diameter of the inhibition zones around the stainless steel cylinder. The data were analyzed by using ANOVA followed by LSD test with significance level of 5%. The results of this study showed that after being incubated for 24 and 48 hours, all flavonoid concentrations significantly (p < 0.05 inhibited the growth of S mutans. 0.1% flavonoid was the most effective concentration to inhibit the growth of S mutans after 24 hours of incubation and 0.5% flavonoid after 48 hours of incubator.

Privacy preserving interactive record linkage (PPIRL).

Science.gov (United States)

Kum, Hye-Chung; Krishnamurthy, Ashok; Machanavajjhala, Ashwin; Reiter, Michael K; Ahalt, Stanley

2014-01-01

Record linkage to integrate uncoordinated databases is critical in biomedical research using Big Data. Balancing privacy protection against the need for high quality record linkage requires a human-machine hybrid system to safely manage uncertainty in the ever changing streams of chaotic Big Data. In the computer science literature, private record linkage is the most published area. It investigates how to apply a known linkage function safely when linking two tables. However, in practice, the linkage function is rarely known. Thus, there are many data linkage centers whose main role is to be the trusted third party to determine the linkage function manually and link data for research via a master population list for a designated region. Recently, a more flexible computerized third-party linkage platform, Secure Decoupled Linkage (SDLink), has been proposed based on: (1) decoupling data via encryption, (2) obfuscation via chaffing (adding fake data) and universe manipulation; and (3) minimum information disclosure via recoding. We synthesize this literature to formalize a new framework for privacy preserving interactive record linkage (PPIRL) with tractable privacy and utility properties and then analyze the literature using this framework. Human-based third-party linkage centers for privacy preserving record linkage are the accepted norm internationally. We find that a computer-based third-party platform that can precisely control the information disclosed at the micro level and allow frequent human interaction during the linkage process, is an effective human-machine hybrid system that significantly improves on the linkage center model both in terms of privacy and utility.

Flavonoids are systemically induced by UV-B in Zea mays

International Nuclear Information System (INIS)

Tossi, V.E.; Lamattina, L.; Cassia, R.

2009-01-01

Flavonoid concentration is increased by UV-B irradiation, but it is unknown if this is a local or systemic response. Nitric oxide (NO) is a diffusible molecule involved in the UV-B response. NO regulates the expression of chalcone synthase (CHS), a key enzyme in the synthesis of flavonoids. The aim of this work was to determine if maize flavonoids are local or systemically induced by UV-B, and what is the participation of NO in this response. We have used maize seedlings where the second leaf was sprayed with H 2 O or cPTIO (a NO scavenger), and then completely covered (C), partially covered (P) or uncovered (U) before to be UV-B irradiated. The results show a 60% increase in the NO concentration of U, 42% in P and 35% in C respectively. Flavonoid concentration increased 90% in C, 70% in P and 40% in U. Flavonoid concentration was reduced when leaves were pretreated with cPTIO before the UV-B irradiation. RT-PCR shows that CHS was up-regulated by UV-B in U, P and C, but downregulated with cPTIO. We have analyzed the subcellular localization of flavonoid and NO in UV-B irradiated plants. Flavonoid localization was coincident with the NO presence in the irradiated surface of the leaves and flavonoids were detected in vesicles. These results indicate that flavonoids are systemically induced by UV-B in a NO-related mechanism. (authors)

Dietary Flavonoids and Gastric Cancer Risk in a Korean Population

Directory of Open Access Journals (Sweden)

Hae Dong Woo

2014-11-01

Full Text Available Gastric cancer is the most common cancer among men in Korea, and dietary factors are closely associated with gastric cancer risk. We performed a case-control study using 334 cases and 334 matched controls aged 35–75 years. Significant associations were observed in total dietary flavonoids and their subclasses, with the exception of anthocyanidins and isoflavones (OR (95% CI: 0.49 (0.31–0.76, p trend = 0.007 for total flavonoids. However, these associations were not significant after further adjustment for fruits and vegetable consumption (OR (95% CI: 0.62 (0.36–1.09, p trend = 0.458 for total flavonoids. Total flavonoids and their subclasses, except for isoflavones, were significantly associated with a reduced risk gastric cancer in women (OR (95% CI: 0.33 (0.15–0.73, p trend = 0.001 for total flavonoids but not in men (OR (95% CI: 0.70 (0.39–1.24, p trend = 0.393 for total flavonoids. A significant inverse association with gastric cancer risk was observed in flavones, even after additional adjustment for fruits and vegetable consumption in women. No significantly different effects of flavonoids were observed between H. pylori-positive and negative subjects. In conclusion, dietary flavonoids were inversely associated with gastric cancer risk, and these protective effects of dietary flavonoids were prominent in women. No clear differences were observed in the subgroup analysis of H. pylori and smoking status.

Silver complexation and tandem mass spectrometry for differentiation of isomeric flavonoid diglycosides.

Science.gov (United States)

Zhang, Junmei; Brodbelt, Jennifer S

2005-03-15

For detection and differentiation of isomeric flavonoids, electrospray ionization mass spectrometry is used to generate silver complexes of the type (Ag + flavonoid)+. Collisionally activated dissociation (CAD) of the resulting 1:1 silver/flavonoid complexes allows isomer differentiation of flavonoids. Eighteen flavonoid diglycosides constituting seven isomeric series are distinguishable from each other based on the CAD patterns of their silver complexes. Characteristic dissociation pathways allow identification of the site of glycosylation, the type of disaccharide (rutinose versus neohesperidose), and the type of aglycon (flavonol versus flavone versus flavanone). This silver complexation method is more universal than previous metal complexation methods, as intense silver complexes are observed even for flavonoids that lack the typical metal chelation sites. To demonstrate the feasibility of using silver complexation and tandem mass spectrometry to characterize flavonoids in complex mixtures, flavonoids extracted from grapefruit juice are separated by high-performance liquid chromatography and analyzed via a postcolumn complexation ESI-MS/MS strategy. Diagnostic fragmentation pathways of the silver complexes of the individual eluting flavonoids allow successful identification of the six flavonoids in the extract.

The Role of Flavonoids as Potential Radioprotectors

International Nuclear Information System (INIS)

Benkovic, V.; Djikic, D.; Horvat Knezevic, A.; Lisicic, D.; Orsolic, N.; Kopjar, N.

2011-01-01

Investigations for effective and non toxic compounds with radioprotection capability led to increasing interest in naturally occurring antioxidants since most of known chemical radioprotectors (AET, WR2721, WR 1065, etc.) express toxic side effects that limit their use in medical practice. Among the promissing compounds there are flavonoids, whosentioxidant activity is based on ability of direct free radicals scavenging or stabilizing the reactive oxygen species (ROS) by interacting with the reactive compound of the radical. Because of the high reactivity of the hydroxyl substituents of flavonoids, radicals are made inactive. Flavonoids can also increase the function of the endogenous antioxidant enzyme systems: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and gluthation. Antioxidant effects may be also a combined result of radical scavenging and interaction with enzyme functions. Flavonoids induce activities of the immune system as well. Increased hematopoietic activity could account for the improved hematopoietic tolerance to radiotherapy. In this study we evaluated radioprotective effects of selected flavonoids (caffeic acid, chrysin, naringin and quercetin) administered to mice prior to whole-body irradiation with γ-rays (absorbed dose was 9 Gy). The survival analysis and alkaline comet assay on white blood cells were employed both on irradiated and non-irradiated animals. Blood samples were taken 30 min. after irradiation. Appropriate negative and positive control groups (administered chemical radioprotector AET, S-(2-Aminoethyl) isothiouronium bromide hydrobromide, i. p. at a dose of 281 mg kg -1 body weight) were also selected and handled in the same manner. We observed statistically significant difference in surviving time of mice pre-treated with test components and the most effective radioprotector was quercetin. Tested flavonoids were not genotoxic to non-irradiated mice and offered good

Flavonoids in baby spinach (Spinacia oleracea L.): Changes during plant growth and storage

DEFF Research Database (Denmark)

Bergquist, S. Å. M.; Gertsson, U. E.; Knuthsen, Pia

2005-01-01

were analyzed by reversed phase HPLC. Twelve flavonoid peaks were detected. The main flavonoid, making up on average 43% of the total flavonoid concentration, was identified as 5,3',4'-trihydroxy-3-methoxy-6:7-methylenedioxyflavone-4'-glucuronide. Four other flavonoids each contributed 7......The variation in flavonoid concentration and composition was investigated in baby spinach (Spinacia oleracea L.) cv. Emilia sown on three occasions, each harvested at three growth stages at 6-day intervals. After harvest, leaves were stored in polypropylene bags at 2 or 10 degrees C. Flavonoids......-12% of the total flavonoid content. Total flavonoid content was relatively stable during normal retail storage conditions, although some of the individual flavonoid compounds showed considerable variation. The youngest plants had the highest flavonoid concentration, indicating that by harvesting the baby spinach...

Absorption, metabolism and health effects of dietary flavonoids in man.

NARCIS (Netherlands)

Hollman, P.C.H.; Katan, M.B.

1997-01-01

Flavonoids are polyphenolic compounds that occur ubiquitously in foods of plant origin. Over 4,000 different flavonoids have been described, and they are categorized into flavonols, flavones, catechins, flavanones, anthocyanidins and isoflavonoids. Flavonoids have a variety of biological effects in

Functional Characterization of a Flavonoid Glycosyltransferase in Sweet Orange (Citrus sinensis).

Science.gov (United States)

Liu, Xiaogang; Lin, Cailing; Ma, Xiaodi; Tan, Yan; Wang, Jiuzhao; Zeng, Ming

2018-01-01

Fruits of sweet orange ( Citrus sinensis ), a popular commercial Citrus species, contain high concentrations of flavonoids beneficial to human health. These fruits predominantly accumulate O -glycosylated flavonoids, in which the disaccharides [neohesperidose (rhamnosyl-α-1,2-glucose) or rutinose (rhamnosyl-α-1,6-glucose)] are linked to the flavonoid aglycones through the 3- or 7-hydroxyl sites. The biotransformation of the flavonoid aglycones into O -rutinosides or O -neohesperidosides in the Citrus plants usually consists of two glycosylation reactions involving a series of uridine diphosphate-sugar dependent glycosyltransferases (UGTs). Although several genes encoding flavonoid UGTs have been functionally characterized in the Citrus plants, full elucidation of the flavonoid glycosylation process remains elusive. Based on the available genomic and transcriptome data, we isolated a UGT with a high expression level in the sweet orange fruits that possibly encodes a flavonoid glucosyltransferase and/or rhamnosyltransferase. Biochemical analyses revealed that a broad range of flavonoid substrates could be glucosylated at their 3- and/or 7-hydrogen sites by the recombinant enzyme, including hesperetin, naringenin, diosmetin, quercetin, and kaempferol. Furthermore, overexpression of the gene could significantly increase the accumulations of quercetin 7- O -rhamnoside, quercetin 7- O -glucoside, and kaempferol 7- O -glucoside, implying that the enzyme has flavonoid 7- O -glucosyltransferase and 7- O -rhamnosyltransferase activities in vivo .

THE SYSTEMATIC AND EVOLUTIONARY SIGNIFICANCE OF EXUDATE FLAVONOIDS IN AEONIUM

NARCIS (Netherlands)

STEVENS, JF; HART, HT; WOLLENWEBER, E

Leaf exudates of 32 species of Aeonium were examined for the presence of flavonoids. Thirty two flavonoids were detected in exudates of half of the species. The flavonoids were identified as methyl ethers of kaempferol, 6-hydroxykaempferol, quercetin, myricetin and scutellarein. The distribution of

FLAVONOID NATURAL SOURCES AND THEIR IMPORTANCE IN THE HUMAN DIET

Directory of Open Access Journals (Sweden)

Martina Danihelová

2011-12-01

Full Text Available Flavonoids as natural bioactive compounds are present in almost every sort of fruits, vegetables and from them derived products. Flavonols may be found mainly in fruits and vegetables, while flavones are abundant in herbs and spices. Rich natural sources of flavanols are tea, cocoa, grape seeds or apple skin. Flavanones are primarily found in a variety of citrus fruits and anthocyanidins in many coloured berries. Soy is rich in isoflavonoids. Average daily intake of flavonoids is approximately in the range of 150 to 300 mg. It strongly depends on individual, country and culture usages. In west countries main dietary sources of flavonoids consist of tea, wine and fruits, while in east countries there is consumed mainly soy with high isoflavonoid content. Many studies have shown, that intake of fruits and vegetables with high flavonoid content is associated with lowered risk of incidence of some diseases such as cardiovascular or cancer. These findings are attributed to experimentally confirmed biological effects of flavonoids - antioxidant, anti-inflammatory, anti-allergic, anticancer or cardioprotective. The final effect is however depending on their bioavailability, which is in the case of flavonoids not high, because in the nature dominating flavonoid glycosides can poorly penetrate through lipophilic cell membranes. Final effective molecules are flavonoid metabolites, that more or less retain their biological activities. doi: 10.5219/160

Strains for the production of flavonoids from glucose

Energy Technology Data Exchange (ETDEWEB)

Stephanopoulos, Gregory; Santos, Christine; Koffas, Mattheos

2015-11-13

The invention relates to the production of flavonoids and flavonoid precursors in cells through recombinant expression of tyrosine ammonia lyase (TAL), 4-coumarate:CoA ligase (4CL), chalcone synthase (CHS), and chalcone isomerase (CHI).

A quest for staunch effects of flavonoids: Utopian protection against hepatic ailments

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Anju Dhiman

2016-11-01

Full Text Available The role of flavonoids as the major red, blue and purple pigments in plants has gained these secondary products a great deal of attention over the years. Flavonoids are polyphenols and occur as aglycones, glycosides and methylated derivatives. Flavonoids are the main components of a healthy diet containing fruits and vegetables and are concentrated especially in tea, apples and onions. Till date, more than 6000 flavonoids have been discovered, out of which 500 are found in free state. They are abundant in polygonaceae, rutaceae, leguminosae, umbelliferae and compositae. Flavonoids are powerful antioxidants. In addition to their role in nutrition, flavonoids possess many types of pharmacological activities, including anti-inflammatory, antioxidative, hepatoprotective, vasorelaxant, antiviral and anticarcinogenic effects. The present review is focused on flavonoids derived from natural products that have shown a wise way to get a true and potentially rich source of drug candidates against liver ailments. The present review initially highlights the current status of flavonoids and their pharmaceutical significance, role of flavonoids in hepatoprotection, therapeutic options available in herbal medicines and in later section, summarizes flavonoids as lead molecules, which have shown significant hepatoprotective activities.

The therapeutic potential of plant flavonoids on rheumatoid arthritis.

Science.gov (United States)

Hughes, Samuel D; Ketheesan, Natkunam; Haleagrahara, Nagaraja

2017-11-22

Rheumatoid arthritis (RA) is an autoimmune condition that mainly affects peripheral joints. Although immunosuppressive drugs and non-steroidal anti-inflammatory drugs (NSAIDs) are used to treat this condition, these drugs have severe side effects. Flavonoids are the most abundant phenolic compounds which exhibit anti-oxidant, anti-inflammatory and immunomodulatory properties. Many bioactive flavonoids have powerful anti-inflammatory effects. However, a very few have reached clinical use. Dietary flavonoids have been reported to control joint inflammation and alleviate arthritis symptoms in both human RA and animal models of arthritis. There is little scientific evidence about their mechanism of actions in RA. We review the therapeutic effects of different groups of flavonoids belonging to the most common and abundant groups on RA. In particular, the probable mechanisms of major flavonoids on cells and chemical messengers involved in the inflammatory signaling components of RA are discussed in detail.

Is reversal of endothelial dysfunction by tea related to flavonoid metabolism?

Science.gov (United States)

Hodgson, Jonathan M; Puddey, Ian B; Burke, Valerie; Croft, Kevin D

2006-01-01

Dietary flavonoids can improve endothelial function, but the response varies between individuals. Wide variability is also seen in flavonoid O-methylation, a major pathway of flavonoid metabolism. The O-methylation of flavonoids could alter activity, and thus influence any effect on endothelial function. The objective of the current analysis was to investigate whether variability in the endothelial function response to ingestion of tea, a rich source of flavonoids, is related to the degree of O-methylation of flavonoids. This relationship was investigated in two studies in which endothelium-dependent flow-mediated dilatation (FMD) of the brachial artery was assessed and urinary 4-O-methylgallic acid (4OMGA) excretion was used as a marker of the O-methylation of tea-derived flavonoids. In the first study, amongst participants consuming five cups of tea per day for 4 weeks, the degree of increase in 4OMGA excretion was inversely associated with the change in FMD responses (r -078, P=0.008). In the second study, there was a significant difference in the FMD responses to acute ingestion of three cups of tea between individuals with a low (median) 4OMGA response (1.94 (sem 0.79) % and -0.25 (sem 0.53) %, respectively; P=0.03). That is, any improvement in FMD following ingestion of tea may be enhanced in individuals who O-methylate less of the absorbed flavonoids. The present results are consistent with the suggestion that differences in flavonoid metabolism may influence their effect on endothelial function. Thus, differences in flavonoid metabolism could be related to the level of benefit of dietary flavonoids on the risk of CVD.

Intrinsic bitterness of flavonoids and isoflavonoids and masking of their taste activity

NARCIS (Netherlands)

Roland, W.S.U.

2014-01-01

Many flavonoids and isoflavonoids have been associated with beneficial health effects. Therefore, consumption of (iso)flavonoid-rich food products, and enrichment of foods with (iso)flavonoids is becoming increasingly popular. However, several (iso)flavonoids have been reported as bitter.

Genotypic variation in tree growth and selected flavonoids in leaves ...

African Journals Online (AJOL)

Growth and flavonoid content varied significantly among different families, and isoquercitrin was the main component of the individual flavonoids, followed by kaempferol and quercetin. Both total and individual flavonoids showed seasonal variation, with the mean highest contents of quercetin and isoquercitrin in July but the ...

Genome scan for linkage to asthma using a linkage disequilibrium-lod score test.

Science.gov (United States)

Jiang, Y; Slager, S L; Huang, J

2001-01-01

We report a genome-wide linkage study of asthma on the German and Collaborative Study on the Genetics of Asthma (CSGA) data. Using a combined linkage and linkage disequilibrium test and the nonparametric linkage score, we identified 13 markers from the German data, 1 marker from the African American (CSGA) data, and 7 markers from the Caucasian (CSGA) data in which the p-values ranged between 0.0001 and 0.0100. From our analysis and taking into account previous published linkage studies of asthma, we suggest that three regions in chromosome 5 (around D5S418, D5S644, and D5S422), one region in chromosome 6 (around three neighboring markers D6S1281, D6S291, and D6S1019), one region in chromosome 11 (around D11S2362), and two regions in chromosome 12 (around D12S351 and D12S324) especially merit further investigation.

Flavonoids from leaves of Mauritia flexuosa

Directory of Open Access Journals (Sweden)

Djalma M. de Oliveira

2013-09-01

Full Text Available The chromatographic fractionation of the Mauritia flexuosa L. f., Arecaceae, leaves extract, a plant known by the name of buriti palm tree, resulted in the isolation of six flavonoids: tricin-7-O-rutinoside, apigenin-6-C-arabinoside, 8-C-glucoside (isoschaftoside, kaempferol-3-O-rutinoside (nicotiflorine, quercetin-3-O-rutinoside (rutin, luteolin-8-C-glucoside (orientin and luteolin-6-C-glucoside (isoorientin. The flavonoids were found out and previously reported as constituents of the Arecaceae family plants, but the occurrence of C-glucoside flavonoids, in the species being analyzed, is described for the first time on this study. The structural elucidations of all of the isolated compounds were performed by means of the comparison of their spectral data (¹H and 13C NMR, UV and ESI-MS with those ones of the literature.

Extraction, isolation and identification of flavonoid from Euphorbia neriifolia leaves

Directory of Open Access Journals (Sweden)

Veena Sharma

2017-05-01

Full Text Available The flavonoids contained in Euphorbia neriifolia leaves were extracted, identified and characterized. Direct and sequential soxhlet extraction and its concentrated fractions were subjected to thin layer chromatography and high performance thin layer chromatography. The results showed that maximum yield of the flavonoid (6.53 g was obtained from ethanolic extract. The Rf value of isolated flavonoid and phytochemical screening has been compared with standard Quercetin. Characterization of isolated flavonoid was done by IR, 1H NMR, and MS. On the basis of chemical and spectral analysis structure was elucidated as 2-(3,4-dihydroxy-5-methoxy-phenyl-3,5-dihydroxy-6,7-dimethoxychromen-4-one, a flavonoid. This compound was isolated for the first time from this plant.

A fluorescence quenching test for the detection of flavonoid transformation.

Science.gov (United States)

Schoefer, L; Braune, A; Blaut, M

2001-11-13

A novel fluorescence quenching test for the detection of flavonoid degradation by microorganisms was developed. The test is based on the ability of the flavonoids to quench the fluorescence of 1,6-diphenyl-1,3,5-hexatriene (DPH). Several members of the anthocyanidins, flavones, isoflavones, flavonols, flavanones, dihydroflavanones, chalcones, dihydrochalcones and catechins were tested with regard to their quenching properties. The anthocyanidins were the most potent quenchers of DPH fluorescence, while the flavanones, dihydroflavanones and dihydrochalcones, quenched the fluorescence only weakly. The catechins had no visible impact on DPH fluorescence. The developed test allows a quick and easy differentiation between flavonoid-degrading and flavonoid-non-degrading bacteria. The investigation of individual reactions of flavonoid transformation with the developed test system is also possible.

Total phenolics and total flavonoids in selected Indian medicinal plants.

Science.gov (United States)

Sulaiman, C T; Balachandran, Indira

2012-05-01

Plant phenolics and flavonoids have a powerful biological activity, which outlines the necessity of their determination. The phenolics and flavonoids content of 20 medicinal plants were determined in the present investigation. The phenolic content was determined by using Folin-Ciocalteu assay. The total flavonoids were measured spectrophotometrically by using the aluminium chloride colorimetric assay. The results showed that the family Mimosaceae is the richest source of phenolics, (Acacia nilotica: 80.63 mg gallic acid equivalents, Acacia catechu 78.12 mg gallic acid equivalents, Albizia lebbeck 66.23 mg gallic acid equivalents). The highest total flavonoid content was revealed in Senna tora which belongs to the family Caesalpiniaceae. The present study also shows the ratio of flavonoids to the phenolics in each sample for their specificity.

VT Wildlife Linkage Habitat

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) The Wildlife Linkage Habitat Analysis uses landscape scale data to identify or predict the location of potentially significant wildlife linkage...

Flavonoids and platelet aggregation: A brief review.

Science.gov (United States)

Faggio, Caterina; Sureda, Antoni; Morabito, Silvia; Sanches-Silva, Ana; Mocan, Andrei; Nabavi, Seyed Fazel; Nabavi, Seyed Mohammad

2017-07-15

Platelets are small anucleated fragments derived from a megakaryocyte precursor. Platelets play a key role in many physiological functions especially in hemostasis and wound healing processes in order to maintain the integrity of the circulatory system. In addition, activated platelets release cytokines and chemokines which modulate the immune response and, in some cases of hyperactivation, they could be associated to the pathogenesis of inflammatory diseases. Flavonoids are polyphenolic compounds ubiquosly found in plants known to be potent antioxidants with positive effects against diverse diseases such as cancer, neurodegenerative or cardiovascular disease. It has been reported that some flavonoids possess anti-platelet aggregation effects though different pathways, being the inhibition of the arachidonic acid-based pathway the most representative mechanism of action. In the present review, the main sources of flavonoids, as well as their bioavailability and metabolism are summarized. Moreover, the available data about the anti-aggregation effects of flavonoids and the different mechanisms of action that has been proposed until now are also discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

The flavonoid biosynthetic pathway in plants: function and evolution

International Nuclear Information System (INIS)

Koes, R.E.; Quattrocchio, F.; Mol, J.N.M.

1994-01-01

Flavonoids are a class of low molecular weight phenolic compounds that is widely distributed in the plant kingdom. They exhibit a diverse spectrum of biological functions and play an important role in the interaction between plants and their environment. Flavonoids not only protect the plant from the harmful effects of UV irradiation but also play a crucial role in the sexual reproduction process. A special class of flavonoid polymers, the tannins, plays a structural role in the plant. Yet other classes of flavonoids, flavonols and anthocyanins, have been implicated in the attraction of pollinators. Certain flavonoids participate in the interaction between plants and other organisms such as symbiotic bacteria and parasites. This raises the intriguing question as to how these different compounds arose and evolved. Based on taxonomy and molecular analysis of gene expression patterns it is possible to deduce a putative sequence of acquisition of the different branches of the biosynthetic pathway and their regulators. (author)

The flavonoid biosynthetic pathway in plants: function and evolution

Energy Technology Data Exchange (ETDEWEB)

Koes, R. E.; Quattrocchio, F.; Mol, J. N.M. [Department of Genetics, Institute for Molecular Biological Sciences, Vrije Universiteit, BioCentrum Amsterdam, De Boelelaan 1087, 1081HV, Amsterdam (Netherlands)

1994-07-01

Flavonoids are a class of low molecular weight phenolic compounds that is widely distributed in the plant kingdom. They exhibit a diverse spectrum of biological functions and play an important role in the interaction between plants and their environment. Flavonoids not only protect the plant from the harmful effects of UV irradiation but also play a crucial role in the sexual reproduction process. A special class of flavonoid polymers, the tannins, plays a structural role in the plant. Yet other classes of flavonoids, flavonols and anthocyanins, have been implicated in the attraction of pollinators. Certain flavonoids participate in the interaction between plants and other organisms such as symbiotic bacteria and parasites. This raises the intriguing question as to how these different compounds arose and evolved. Based on taxonomy and molecular analysis of gene expression patterns it is possible to deduce a putative sequence of acquisition of the different branches of the biosynthetic pathway and their regulators. (author)

Flavonoids at the pharma-nutrition interface: Is a therapeutic index in demand?

Science.gov (United States)

Peluso, Ilaria; Palmery, Maura

2015-04-01

The consumption of flavonoid-rich foods could have beneficial effects on health. However, different classes of flavonoids have different effect on disease risk and the relationship between flavonoid intake and risk of disease appeared to be non-linear. Furthermore, contrarily to vitamins, there are no symptoms of deficiency for flavonoids; therefore, our body treats them like other xenobiotics. Therefore, a therapeutic index should be determined. Despite flavonoids are at the pharma-nutrition interface, drugs and foods are subject to different regulatory frameworks and there is no recommended daily allowance (RDA) for flavonoids. Relatively little is known about the efficacy, safety and underlying mechanisms of these bioactive compounds, especially when taken in concert with drugs. Flavonoids could act both as drugs and pro-drugs with pharmacological and toxicological promiscuity. Due to the low bioavailability, the gastrointestinal tract could be the primary target of flavonoids and metabolites. Different effects have been observed after acute and chronic consumption and bioavailability and bioactivity have high inter-individual variability. Furthermore, the difficulties in the design and in the interpretation of human intervention studies make difficult the establishment of a therapeutic index for flavonoids. Probably the concept of 'personalized nutrition' previously proposed could be the better approach. However, despite more studies are needed in order to establish a therapeutic index for each flavonoid subclasses, at the moment RDA of total flavonoids could be between 250-400 mg/d, respecting the seasonality of food sources. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Antioxidant activity and total phenolic and flavonoid content of ...

African Journals Online (AJOL)

ajl yemi

2011-12-19

Dec 19, 2011 ... Key words: Astragalus squarrosus, antioxidant, phenolics, flavonoids. INTRODUCTION ... Phenolic and flavonoid compounds are widely distri- buted plant constituents. ..... Antioxidant effects of some ginger constituents.

Plant flavonoids in cancer chemoprevention: role in genome stability.

Science.gov (United States)

George, Vazhappilly Cijo; Dellaire, Graham; Rupasinghe, H P Vasantha

2017-07-01

Carcinogenesis is a multistage process that involves a series of events comprising of genetic and epigenetic changes leading to the initiation, promotion and progression of cancer. Chemoprevention is referred to as the use of nontoxic natural compounds, synthetic chemicals or their combinations to intervene in multistage carcinogenesis. Chemoprevention through diet modification, i.e., increased consumption of plant-based food, has emerged as a most promising and potentially cost-effective approach to reducing the risk of cancer. Flavonoids are naturally occurring polyphenols that are ubiquitous in plant-based food such as fruits, vegetables and teas as well as in most medicinal plants. Over 10,000 flavonoids have been characterized over the last few decades. Flavonoids comprise of several subclasses including flavonols, flavan-3-ols, anthocyanins, flavanones, flavones, isoflavones and proanthocyanidins. This review describes the most efficacious plant flavonoids, including luteolin, epigallocatechin gallate, quercetin, apigenin and chrysin; their hormetic effects; and the molecular basis of how these flavonoids contribute to the chemoprevention with a focus on protection against DNA damage caused by various carcinogenic factors. The present knowledge on the role of flavonoids in chemoprevention can be used in developing effective dietary strategies and natural health products targeted for cancer chemoprevention. Copyright © 2016 Elsevier Inc. All rights reserved.

Bioavailability, metabolism and potential health protective effects of dietary flavonoids

DEFF Research Database (Denmark)

Bredsdorff, Lea

Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several epidemiologi......Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several...... of their content. In addition, variation in individual metabolic genotype and microflora may greatly affect the actual flavonoid exposure. The preventive effects of flavonoids on CHD are mainly ascribed to their anti-inflammatory and antioxidant activities. Several mechanisms of anti-inflammatory and antioxidant...... effective absorption of hesperetin and naringenin from the small intestine when consumed as glucosides compared to absorption in the colon VII after microbial degradation of the rhamnoglucosides. In addition it was shown that the conjugate profile was neither affected by the absorption site nor by a 3-fold...

Combinatorial Synthesis of Structurally Diverse Triazole-Bridged Flavonoid Dimers and Trimers

Directory of Open Access Journals (Sweden)

Tze Han Sum

2016-09-01

Full Text Available Flavonoids are a large family of compounds associated with a broad range of biologically useful properties. In recent years, synthetic compounds that contain two flavonoid units linked together have attracted attention in drug discovery and development projects. Numerous flavonoid dimer systems, incorporating a range of monomers attached via different linkers, have been reported to exhibit interesting bioactivities. From a medicinal chemistry perspective, the 1,2,3-triazole ring system has been identified as a particularly attractive linker moiety in dimeric derivatives (owing to several favourable attributes including proven biological relevance and metabolic stability and triazole-bridged flavonoid dimers possessing anticancer and antimalarial activities have recently been reported. However, there are relatively few examples of libraries of triazole-bridged flavonoid dimers and the diversity of flavonoid subunits present within these is typically limited. Thus, this compound type arguably remains underexplored within drug discovery. Herein, we report a modular strategy for the synthesis of novel and biologically interesting triazole-bridged flavonoid heterodimers and also very rare heterotrimers from readily available starting materials. Application of this strategy has enabled step-efficient and systematic access to a library of structurally diverse compounds of this sort, with a variety of monomer units belonging to six different structural subclasses of flavonoid successfully incorporated.

Design of special planar linkages

CERN Document Server

Zhao, Jing-Shan; Ma, Ning; Chu, Fulei

2013-01-01

Planar linkages play a very important role in mechanical engineering. As the simplest closed chain mechanisms, planar four-bar linkages are widely used in mechanical engineering, civil engineering and aerospace engineering.Design of Special Planar Linkages proposes a uniform design theory for planar four-bar linkages. The merit of the method proposed in this book is that it allows engineers to directly obtain accurate results when there are such solutions for the specified n precise positions; otherwise, the best approximate solutions will be found. This book discusses the kinematics and reach

Extraction and determination of total flavonoids in jujube by alcohol extraction

Science.gov (United States)

Ji, Y. B.; Ru, X.; Yu, M.; Wang, S. W.; Lu, L.; Qiao, A. N.; Guo, A. Z.

2017-12-01

Jujube is a ripe fruit of Rhamnaceae. Its main active component is flavonoids, so the extraction and determination of total flavonoids in jujube will help to develop and utilize the medicinal value of jujube. In this study, the total flavonoids were extracted from jujube by alcohol extraction method. Through single factor investigation and orthogonal test, it was found that the total flavonoids content in jujube was the highest under the condition of 70°C, material ratio of 1:40, and extraction of 30 min by 70% ethanol. The content of total flavonoids in the extract of jujube was 1.57% at the wavelength of 510 nm by UV and rutin as the standard. The method was evaluated by methodological study, and it was determined that this method could be used as the detection of total flavonoids in jujube extraction.

Physico-chemical study of flavonoids from different matureness corn silk material

OpenAIRE

Li, Peng; Lapčík, Lubomír; Lapčíková, Barbora; Kalytchuk, Sergii

2018-01-01

There was tested a simple extraction procedure of flavonoids separation from the original corn silk (CS) material. It was found, that the total flavonoids content differs with the extraction time and extraction temperature. There were found different flavonoids contents in extracts prepared from different maturity stages of the original corn silk material (silking stage (CS-S), milky stage (CS-M)). Extracted flavonoids content was quantified by the lutin standardization method by means of col...

Antimicrobial potential of alkaloids and flavonoids extracted from ...

African Journals Online (AJOL)

Background: Alkaloids and flavonoids are secondary metabolites extracted from different medicinal plants. Tamarix aphylla a traditionally valuable medicinal plant; was used for the extraction of alkaloids and flavonoids in order to evaluate their antibacterial activity. Methodology: The leaves of the plant were collected from ...

Ultrasonic-Assisted Extraction and Antioxidant Activity of Flavonoids ...

African Journals Online (AJOL)

Purpose: To identify the main flavonoid in Adinandra nitida leaf, employ response surface methodology to optimize its ultrasonic-assisted extraction, and determine the antioxidant activity of the obtained extract. Methods: The main flavonoid in Adinandra nitida leaf was obtained by traditional solvent extraction and ...

Luteolin, a flavonoid, inhibits AP-1 activation by basophils

International Nuclear Information System (INIS)

Hirano, Toru; Higa, Shinji; Arimitsu, Junsuke; Naka, Tetsuji; Ogata, Atsushi; Shima, Yoshihito; Fujimoto, Minoru; Yamadori, Tomoki; Ohkawara, Tomoharu; Kuwabara, Yusuke; Kawai, Mari; Matsuda, Hisashi; Yoshikawa, Masayuki; Maezaki, Naoyoshi; Tanaka, Tetsuaki; Kawase, Ichiro; Tanaka, Toshio

2006-01-01

Flavonoids including luteolin, apigenin, and fisetin are inhibitors of IL-4 synthesis and CD40 ligand expression by basophils. This study was done to search for compounds with greater inhibitory activity of IL-4 expression and to clarify the molecular mechanisms through which flavonoids inhibit their expression. Of the 37 flavonoids and related compounds examined, ayanin, luteolin, and apigenin were the strongest inhibitors of IL-4 production by purified basophils in response to anti-IgE antibody plus IL-3. Luteolin did not suppress Syk or Lyn phosphorylation in basophils, nor did suppress p54/46 SAPK/JNK, p38 MAPK, and p44/42 MAPK activation by a basophilic cell line, KU812 cells, stimulated with A23187 and PMA. However, luteolin did inhibit phosphorylation of c-Jun and DNA binding activity of AP-1 in nuclear lysates from stimulated KU812 cells. These results provide a fundamental structure of flavonoids for IL-4 inhibition and demonstrate a novel action of flavonoids that suppresses the activation of AP-1

Flavonoids Inhibit the Respiratory Burst of Neutrophils in Mammals

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Milan Ciz

2012-01-01

Full Text Available Neutrophils represent the front-line defence cells in protecting organisms against infection and play an irreplaceable role in the proper performance of the immune system. As early as within the first minutes of stimulation, neutrophilic NADPH oxidase is activated, and cells release large quantities of highly toxic reactive oxygen species (ROS. These oxidants can be highly toxic not only for infectious agents but also for neighboring host tissues. Since flavonoids exhibit antioxidant and anti-inflammatory effects, they are subjects of interest for pharmacological modulation of ROS production. The present paper summarizes contemporary knowledge on the effects of various flavonoids on the respiratory burst of mammalian neutrophils. It can be summarized that the inhibitory effects of flavonoids on the respiratory burst of phagocytes are mediated via inhibition of enzymes involved in cell signaling as well as via modulation of redox status. However, the effects of flavonoids are even more complex, and several sites of action, depending upon the flavonoid structure and way of application, are included.

Efficacy of Food Proteins as Carriers for Flavonoids

NARCIS (Netherlands)

Bohin, M.C.; Vincken, J.P.; Hijden, H.T.W.M.; Gruppen, H.

2012-01-01

Enrichment of flavonoids in food is often limited by their off-tastes, which might be counteracted by the use of food proteins as carriers of flavonoids. Various milk proteins, egg proteins, and gelatin hydrolysates were compared for their binding characteristics to two flavan-3-ols. Among the

Efficient Record Linkage Algorithms Using Complete Linkage Clustering.

Science.gov (United States)

Mamun, Abdullah-Al; Aseltine, Robert; Rajasekaran, Sanguthevar

2016-01-01

Data from different agencies share data of the same individuals. Linking these datasets to identify all the records belonging to the same individuals is a crucial and challenging problem, especially given the large volumes of data. A large number of available algorithms for record linkage are prone to either time inefficiency or low-accuracy in finding matches and non-matches among the records. In this paper we propose efficient as well as reliable sequential and parallel algorithms for the record linkage problem employing hierarchical clustering methods. We employ complete linkage hierarchical clustering algorithms to address this problem. In addition to hierarchical clustering, we also use two other techniques: elimination of duplicate records and blocking. Our algorithms use sorting as a sub-routine to identify identical copies of records. We have tested our algorithms on datasets with millions of synthetic records. Experimental results show that our algorithms achieve nearly 100% accuracy. Parallel implementations achieve almost linear speedups. Time complexities of these algorithms do not exceed those of previous best-known algorithms. Our proposed algorithms outperform previous best-known algorithms in terms of accuracy consuming reasonable run times.

North-South Business Linkages

DEFF Research Database (Denmark)

Sørensen, Olav Jull; Kuada, John

2006-01-01

Based on empirical studies of linkages between TNCs and local firms in India, Malaysia, Vietnam, Ghana and South Africa, five themes are discussed and related to present theoretical perspectives. The themes are (1) Linakge Governance; (2) Globalisation and the dynamics in developing countries (the...... TNC-driven markets in developing countries); (3) The upgrading impact of FDI; (4) Non-equity linkages as a platform for business development, and (5) The learning perspective on international business linakges. The chapter offers at the end a three-dimanional model for impacts of business linkages....

Flavonoids Active Against Osteosarcoma: A Review of the Molecular Mechanisms Involved.

Science.gov (United States)

Liu, Hui; Gao, Yutong; Dong, Yonghui; Cheng, Peng; Chen, Anmin; Huang, Hui

2017-01-01

Osteosarcoma is the most frequent primitive malignant bone tumor affecting adolescents and young adults worldwide. The tumor exhibits aggressive growth in the primary site and readily metastasizes to other organs. There has been no significant improvement in the 5-year survival rate since the 1970s and the figure remains at 60-70%. In addition, the side effects of chemotherapeutic drugs and resistance to chemotherapy compromise the effects of treatment for osteosarcoma. In recent years, the development of flavonoids drugs inhibiting carcinogenesis is attracting great interest in the scientific community. Flavonoids are one kind of polyphenolic compounds widely found in vegetables and fruits. Moreover, flavonoids have become popular compounds, exhibiting comprehensive antitumor activities, while being safe and inexpensive. Here, the literature on the benefits afforded by flavonoids in terms of osteosarcoma treatment is reviewed and certain flavonoids and their effects on osteosarcoma are discussed. These compounds can perturb the cell cycle, induce apoptosis, inhibit tumor cell invasion and metastasis, potentiate the actions of chemotherapeutic agents, trigger autophagy, and stimulate antitumor activity in vivo. In summary, we highlight the currently well-accepted flavonoid compounds and detail the molecular mechanisms by which flavonoids may treat osteosarcoma, and thus the flavonoids exhibit great promise as anti-osteosarcoma agents. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Chemical sensing of Benzo[a]pyrene using Corchorus depressus fluorescent flavonoids.

Science.gov (United States)

Ahmad, Wajiha; Rana, Nosheen Fatima; Riaz, Sundus; Ahmad, Nasir Mehmood; Hameed, Maryam; Naeem, Ayesha; Tahir, Rabbiya

2018-04-01

Plant phytochemicals, such as flavonoids are in use for the development of optical biosensor. Benzo[a]pyrene (B[a]P), is a pervasive environmental and dietary carcinogen. A fluorescent assay is developed using plant isolated flavonoid for the detection of B[a]P. High content saponins are excluded from the flavonoid-containing methanolic extract of Corchorus depressus by implying reduction of silver ions by saponins resulting in formation of silver nanoparticles. Isolated plant flavonoids are used to develop a spectrofluorometric assay for the detection of B[a]P. Decrease in the flavonoid fluorescence intensity by B[a]P is found to be based on both static and dynamic quenching. Specificity of the assay for B[a]P was tested for other carcinogens belonging to different classes of compounds. Flavonoids-mediated sensing can be implied for the development of new generation of nanoparticle-based biosensors that can be more sensitive and less susceptible to external factors, such as temperature and humidity.

Cytotoxicity of flavonoid glycosides, flavonoids and phenolic acids from Inula oculus-christi on mammalian cell lines

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Ralitsa K. Veleva

2016-12-01

Full Text Available Herbs of the genus Inula are well known in traditional medicine. Their extracts are used as expectorants, antitussives, bactericides as well as for the treatment of lung inflammation and have shown to possess anti-inflammatory and secretolytic activity. Experimental research findings indicate the anti-tumor effect of certain components of extracts from Inula cappa and Inula britannicа and those from Inula racemosa have antimicrobial and antidiabetic activity. We have directed our efforts on investigating the effects of different extracts from Inula oculus-christi, enriched with certain groups of biologically active substances - flavonoid glycosides (A, phenolic acids (B, flavonoid glycosides and phenolic acids (C, flavonoids and phenolic acids (D. The effect of these extracts on normal (MDCK ІІ and RPE1 and carcinoma cell lines (A549 and HepG2 was evaluated. We have performed cytotoxicity study (crystal violet assay as well as morphological analysis of changes induced by the extracts. Among the tumor cell lines HepG2 show greater sensitivity. Surprisingly extract C has no significant influence on both cancer cell lines.

Inhibition effect on lipid oxidation of irradiated pork by adding hawthorn flavonoid extract

International Nuclear Information System (INIS)

Wang Xiaoming; Liu Chao; Cao Lei; Li Kexi

2011-01-01

The antioxidant activity of hawthorn flavonoid extract and its inhibition effect on irradiated pork lipid oxidant were investigated. The results showed that hawthorn flavonoids had efficient scavenging effect on DPPH free radicals (DPPH ·), and the scavenging rate reached 56% while 2 ml of 0.035 mg/ml hawthorn flavonoid extract was added. Hawthorn flavonoid extract can inhibition the lipid oxidation of irradiated pork effectively and it showed a stronger inhibition ability while the hawthorn flavonoid extract were used together with Vc. It is concluded that can decrease the lipid oxidation of pork, hawthorn flavonoid extract is a remarkable natural antioxidant. (authors)

Dietary flavonoid derivatives enhance chemotherapeutic effect by inhibiting the DNA damage response pathway

International Nuclear Information System (INIS)

Kuo, Ching-Ying; Zupkó, István; Chang, Fang-Rong; Hunyadi, Attila; Wu, Chin-Chung; Weng, Teng-Song; Wang, Hui-Chun

2016-01-01

Flavonoids are the most common group of polyphenolic compounds and abundant in dietary fruits and vegetables. Diet high in vegetables or dietary flavonoid supplements is associated with reduced mortality rate for patients with breast cancer. Many studies have been proposed for mechanisms linking flavonoids to improving chemotherapy efficacy in many types of cancers, but data on this issue is still limited. Herein, we report on a new mechanism through which dietary flavonoids inhibit DNA damage checkpoints and repair pathways. We found that dietary flavonoids could inhibit Chk1 phosphorylation and decrease clonogenic cell growth once breast cancer cells receive ultraviolet irradiation, cisplatin, or etoposide treatment. Since the ATR-Chk1 pathway mainly involves response to DNA replication stress, we propose that flavonoid derivatives reduce the side effect of chemotherapy by improving the sensitivity of cycling cells. Therefore, we propose that increasing intake of common dietary flavonoids is beneficial to breast cancer patients who are receiving DNA-damaging chemotherapy, such as cisplatin or etoposide-based therapy. - Highlights: • First report on inhibition of both DNA damage and repair by dietary flavonoids • Dietary flavonoids inhibit cisplatin- and UV-induced Chk1 phosphorylation. • Flavonoids combined with cisplatin or UV treatment show notable growth inhibition. • Promising treatment proposal for patients who are receiving adjuvant chemotherapy

Dietary flavonoid derivatives enhance chemotherapeutic effect by inhibiting the DNA damage response pathway

Energy Technology Data Exchange (ETDEWEB)

Kuo, Ching-Ying [Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Zupkó, István [Department of Pharmacodynamics and Biopharmacy, University of Szeged, Eötvös Utca 6, Szeged H-6720 (Hungary); Chang, Fang-Rong [Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Hunyadi, Attila [Institute of Pharmacognosy, Faculty of Pharmacy, University of Szeged, Eötvös Utca 6, Szeged H-6720 (Hungary); Wu, Chin-Chung; Weng, Teng-Song [Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Wang, Hui-Chun, E-mail: wanghc@kmu.edu.tw [Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); PhD Program in Translational Medicine, College of Medicine and PhD Program in Toxicology, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Research Center for Natural Product and Drug Development, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Translational Research Center and Cancer Center, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan (China); Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China); Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China)

2016-11-15

Flavonoids are the most common group of polyphenolic compounds and abundant in dietary fruits and vegetables. Diet high in vegetables or dietary flavonoid supplements is associated with reduced mortality rate for patients with breast cancer. Many studies have been proposed for mechanisms linking flavonoids to improving chemotherapy efficacy in many types of cancers, but data on this issue is still limited. Herein, we report on a new mechanism through which dietary flavonoids inhibit DNA damage checkpoints and repair pathways. We found that dietary flavonoids could inhibit Chk1 phosphorylation and decrease clonogenic cell growth once breast cancer cells receive ultraviolet irradiation, cisplatin, or etoposide treatment. Since the ATR-Chk1 pathway mainly involves response to DNA replication stress, we propose that flavonoid derivatives reduce the side effect of chemotherapy by improving the sensitivity of cycling cells. Therefore, we propose that increasing intake of common dietary flavonoids is beneficial to breast cancer patients who are receiving DNA-damaging chemotherapy, such as cisplatin or etoposide-based therapy. - Highlights: • First report on inhibition of both DNA damage and repair by dietary flavonoids • Dietary flavonoids inhibit cisplatin- and UV-induced Chk1 phosphorylation. • Flavonoids combined with cisplatin or UV treatment show notable growth inhibition. • Promising treatment proposal for patients who are receiving adjuvant chemotherapy.

Flavonoids Fight Diseases

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 2. Flavonoids Fight Diseases. G Nagendrappa. Article-in-a-Box Volume 9 Issue 2 February 2004 pp 5-5. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/009/02/0005-0005. Author Affiliations.

Radioprotective effects of antioxidative plant flavonoids in mice

International Nuclear Information System (INIS)

Shimoi, Kayoko; Masuda, Shuichi; Shen, Bingrong; Furugori, Michiyo; Kinae, Naohide

1996-01-01

Radioprotective effects of tea infusions and plant flavonoids were investigated by using the micronucleus test for anticlastogenic activity and the thiobarbituric acid assay for antioxidative activity. A single gastric intubation of rooibos tea (Aspalathus linearis) infusion at 1 ml per mouse 2 h prior to γ-ray irradiation (1.5 Gy) reduced the frequency of micronucleated reticulocytes (MNRETs). After the fractionation of rooibos tea infusion, the flavonoid fraction was found to be most anticlastogenic and antioxidative. From this fraction, luteolin was isolated as an effective component. Then, anticlastogenic effects of 12 flavonoids containing luteolin and their antioxidative activities against lipid peroxidation by Fenton's reagent were examined. A good correlation (r=0.717) was observed between both activities. Luteolin showed the most effective potency. A gastric intubation of luteolin (10 μmol/kg) 2 h prior to γ-ray irradiation (6 Gy) suppressed lipid peroxidation in mouse bone marrow and spleen and a trend of protective effect of luteolin against the decrease of endogenous ascorbic acid in mouse bone marrow after γ-ray irradiation (3 Gy) was observed. These results suggest that plant flavonoids, which show antioxidative potency in vitro, work as antioxidants in vivo and their radioprotective effects may be attributed to their scavenging potency towards free radicals such as hydroxyl radicals. Therefore, the flavonoids contained in tea, vegetables and fruits seem to be important as antioxidants in the human diet

Estimation of dietary flavonoid intake and major food sources of Korean adults.

Science.gov (United States)

Jun, Shinyoung; Shin, Sangah; Joung, Hyojee

2016-02-14

Epidemiological 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.

Dietary flavonoids of Spanish youth: intakes, sources, and association with the Mediterranean diet

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Rowaedh Ahmed Bawaked

2017-05-01

Full Text Available Background Plant-based diets have been linked to high diet quality and reduced risk of cardiovascular diseases. The health impact of plant-based diets might be partially explained by the concomitant intake of flavonoids. Estimation of flavonoids intake in adults has been important for the development of dietary recommendations and interventions for the prevention of weight gain and its consequences. However, estimation of flavonoids intake in children and adolescents is limited. Methods Average daily intake and sources of flavonoids were estimated for a representative national sample of 3,534 children and young people in Spain, aged 2–24 years. The data was collected between 1998 and 2000 by 24-h recalls. The Phenol-Explorer database and the USDA database on flavonoids content were used. Adherence to the Mediterranean diet was measured by the KIDMED index. Results The mean and median intakes of total flavonoids were 70.7 and 48.1 mg/day, respectively. The most abundant flavonoid class was flavan-3-ols (35.7%, with fruit being the top food source of flavonoids intake (42.8%. Total flavonoids intake was positively associated with the KIDMED index (p < 0.001. Conclusion The results of this study provide primary information about flavonoids intake and main food sources in Spanish children, adolescents and young adults. Participants with high daily mean intake of flavonoids have higher adherence to the Mediterranean diet.

Flavonoids in human urine as biomarkers for intake of fruits and vegetables

DEFF Research Database (Denmark)

Nielsen, Salka E.; Freese, R.; Kleemola, P.

2002-01-01

Flavonoids are polyphenolic compounds ubiquitously found in human diets. We have studied the association between urinary excretion of flavonoids and the intake of fruits and vegetables to evaluate the usefulness of flavonoids as a biomarker for fruit and vegetable intake. Levels of 12 dietary...... relevant flavonoids were determined by LC-MS in urine samples collected prior to an intervention study, when the subjects were on their habitual diet (n = 94), and after they had participated in an intervention study with diets either high or low in fruits, berries, and vegetables (n = 77). Both flavonoid...... glycosides and aglycones were included in the assay, but only the flavonoid aglycones were detectable. Thus, the flavonols quercetin, kaempferol, isorhamnetin, and tamarixetin, the dihydrochalcone phloretin, and the flavanones naringenin and hesperetin were quantified in the enzymatically hydrolyzed urine...

Flavonoids in the development of functional meat products: A review

Directory of Open Access Journals (Sweden)

Pramod K. Singh

2013-06-01

Full Text Available Flavonoids or bioflavonoids are unique low molecular weight ubiquitous polyphenolic compounds produced by plants during their metabolic activities as a secondary metabolites and responsible for major organoleptic characteristics and health benefits of plant derived foods. The flavonoids are potent antioxidants agents and protect the cells by scavenging and inhibiting the production and initiation of free radicals, superoxide anions and lipid peroxy radicals. Besides potent antioxidant capacity, flavonoids also shows antimicrobial, antimutagenic, antidiabetic, antithrombosis, antirheumatic, antiatherosclerotic, antiallergic, anti-inflammatory, antiulcers and hepatoprotectives and better termed as neutraceuticals. The antioxidant capacity of meat is very low and this can be increased by adding flavonoids in meat during processing in the form of plant parts rich in flavonoids such as seeds, fruit skin or peel, bark and flower as raw or in extract form without comprising the sensory attributes of meat and meat products. [Vet World 2013; 6(8.000: 573-578

Highly Oxygenated Flavonoids from the Leaves of Nicotiana plumbaginifolia (Solanaceae

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Md. Shafiullah Shajib

2017-11-01

Full Text Available Nicotiana plumbaginifolia Viv. is an annual herb of the family Solanaceae, which grows abundantly in the weedy lands of Bangladesh . This plant possesses analgesic, antibacterial, anti-anxiety and hepatoprotective properties, and produces various phenolic compounds including flavonoids. The present study afforded determination of total phenolic and flavonoid contents, and for the first time, the isolation and characterization of highly oxygenated flavonoids, e.g., 3,3' ,5,6,7,8-hexamethoxy- 4',5'-methylenedioxyflavone (1, 3,3' ,4' ,5',5,6,7,8-octamethoxyflavone (2, exoticin, 6,7,4',5'-dimethylenedioxy-3,5,3'-trimethoxyflavone (3 and ( 3,3' ,4',5,5',8-hexamethoxy-6,7-methylenedioxyflavone (4 from the leaves of N. plumbaginifolia . All these flavonoids are rather rare natural products, and only found in a few genera, e.g.,Polygonum and Murraya. The structures of the isolated flavonoids were elucidated by comprehensive spectroscopic analyses, e.g., UV, 1H, 13C NMR, DEPT, HSQC, HMBC and MS.

Regulation of Flavonoid Biosynthetic Genes in Germinating Arabidopsis Seedlings.

Science.gov (United States)

Kubasek, WL; Shirley, BW; McKillop, A; Goodman, HM; Briggs, W; Ausubel, FM

1992-01-01

Many higher plants, including Arabidopsis, transiently display purple anthocyanin pigments just after seed germination. We observed that steady state levels of mRNAs encoded by four flavonoid biosynthetic genes, PAL1 (encoding phenylalanine ammonia-lyase 1), CHS (encoding chalcone synthase), CHI (encoding chalcone isomerase), and DFR (encoding dihydroflavonol reductase), were temporally regulated, peaking in 3-day-old seedlings grown in continuous white light. Except for the case of PAL1 mRNA, mRNA levels for these flavonoid genes were very low in seedlings grown in darkness. Light induction studies using seedlings grown in darkness showed that PAL1 mRNA began to accumulate before CHS and CHI mRNAs, which, in turn, began to accumulate before DFR mRNA. This order of induction is the same as the order of the biosynthetic steps in flavonoid biosynthesis. Our results suggest that the flavonoid biosynthetic pathway is coordinately regulated by a developmental timing mechanism during germination. Blue light and UVB light induction experiments using red light- and dark-grown seedlings showed that the flavonoid biosynthetic genes are induced most effectively by UVB light and that blue light induction is mediated by a specific blue light receptor. PMID:12297632

Highly Oxygenated Flavonoids from the Leaves of Nicotiana plumbaginifolia (Solanaceae)

OpenAIRE

Md. Shafiullah Shajib; Bidyut Kanti Datta; Md. Hossain Sohrab; Mohammad Abdur Rashid; Lutfun Nahar; Satyajit Dey Sarker

2017-01-01

Nicotiana plumbaginifolia Viv. is an annual herb of the family Solanaceae, which grows abundantly in the weedy lands of Bangladesh . This plant possesses analgesic, antibacterial, anti-anxiety and hepatoprotective properties, and produces various phenolic compounds including flavonoids. The present study afforded determination of total phenolic and flavonoid contents, and for the first time, the isolation and characterization of highly oxygenated flavonoids, e.g., 3,3' ,5,6,7,8-hexamethoxy- 4...

Comparative Developmental Toxicity of Flavonoids Using an Integrative Zebrafish System.

Science.gov (United States)

Bugel, Sean M; Bonventre, Josephine A; Tanguay, Robert L

2016-11-01

Flavonoids are a large, structurally diverse class of bioactive naturally occurring chemicals commonly detected in breast milk, soy based infant formulas, amniotic fluid, and fetal cord blood. The potential for pervasive early life stage exposures raises concerns for perturbation of embryogenesis, though developmental toxicity and bioactivity information is limited for many flavonoids. Therefore, we evaluated a suite of 24 flavonoid and flavonoid-like chemicals using a zebrafish embryo-larval toxicity bioassay-an alternative model for investigating developmental toxicity of environmentally relevant chemicals. Embryos were exposed to 1-50 µM of each chemical from 6 to 120 h postfertilization (hpf), and assessed for 26 adverse developmental endpoints at 24, 72, and 120 hpf. Behavioral changes were evaluated in morphologically normal animals at 24 and 72 hpf, at 120 hpf using a larval photomotor response (LPR) assay. Gene expression was comparatively evaluated for all compounds for effects on biomarker transcripts indicative of AHR (cyp1a) and ER (cyp19a1b, esr1, lhb, vtg) pathway bioactivity. Overall, 15 of 24 flavonoids elicited adverse effects on one or more of the developmental or behavioral endpoints. Hierarchical clustering and principle component analyses compared toxicity profiles and identified 3 distinct groups of bioactive flavonoids. Despite robust induction of multiple estrogen-responsive biomarkers, co-exposure with ER and GPER antagonists did not ameliorate toxicity, suggesting ER-independence and alternative modes of action. Taken together, these studies demonstrate that development is sensitive to perturbation by bioactive flavonoids in zebrafish that are not related to traditional estrogen receptor mode of action pathways. This integrative zebrafish platform provides a useful framework for evaluating flavonoid developmental toxicity and hazard prioritization. © The Author 2016. Published by Oxford University Press on behalf of the Society of

Study the active site of flavonoid applying radiation chemistry

Energy Technology Data Exchange (ETDEWEB)

Wu Jilan; Sun Gang; Zhang Fugen; He Yongke; Li Jiuqiang [Department of Technical Physics, Peking Univ., Beijing (China)

2000-03-01

Flavonoid are a large and important class of naturally occurring, low molecular weight benzo-{gamma}-pyrone derivatives which are reported to have a myriad of biological activities, but the study on the active sites of flavonoids is still ambiguous. In this paper, rutin, quercetin and baicalin have been selected as model compounds. It is well known that rutin is used in inhibiting arteriosclerosis and baicalin is antibacterial and antiviral. They have similar basic structure, but their medicinal properties are so different, why? As most flavonoids contain carbonyl group, which can capture electron effectively, we predict that flavonoids can capture electron to form radical anion. The formation of anion radical may have influence on the mitochondrial electron transport chain. The difference in the ability of forming anion radical may cause the difference in their medicinal effects. (author)

Study the active site of flavonoid applying radiation chemistry

International Nuclear Information System (INIS)

Wu Jilan; Sun Gang; Zhang Fugen; He Yongke; Li Jiuqiang

2000-01-01

Flavonoid are a large and important class of naturally occurring, low molecular weight benzo-γ-pyrone derivatives which are reported to have a myriad of biological activities, but the study on the active sites of flavonoids is still ambiguous. In this paper, rutin, quercetin and baicalin have been selected as model compounds. It is well known that rutin is used in inhibiting arteriosclerosis and baicalin is antibacterial and antiviral. They have similar basic structure, but their medicinal properties are so different, why? As most flavonoids contain carbonyl group, which can capture electron effectively, we predict that flavonoids can capture electron to form radical anion. The formation of anion radical may have influence on the mitochondrial electron transport chain. The difference in the ability of forming anion radical may cause the difference in their medicinal effects. (author)

Effect of flavonoids on human health: old subjects but new challenges.

Science.gov (United States)

Lee, Eung-Ryoung; Kang, Geun-Ho; Cho, Ssang-Goo

2007-01-01

Flavonoids are highly diversified plant pigments that are present in a wide range of fruits, vegetables, nuts, and beverages. They are regularly consumed in the human diet and have various biological activities including anti-inflammatory, anti-cancer, and anti-viral properties. The flavonoids maybe one of the safest non-immunogenic drugs because they are small organic compounds which have been normally absorbed by the human body for long time. During the past decades, the patents on their health effects have inflated very much and the yearly number of the patents is on an increasing trend. This review summarizes the current patents on the health effects of various flavonoids, and suggests the possible expectation that a wide variety of diseases are successful treated with newly-developed specific flavonoids or their derivatives in the near future. In recent patents, specific flavonoids were described to function as anti-oxidants, enzyme inhibitors, hormones, or immune modulators. Moreover, the recent patents also tried to provide the molecular mechanism of the flavonoid compounds on treating or preventing various human diseases. Recent mechanistic studies in molecular level make it possible that specific flavonoids are identified to have a wide range of biological properties that can contribute to the beneficial effects on human health.

Flavonoids as Inhibitors of Human Butyrylcholinesterase Variants

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Maja Katalinić

2014-01-01

Full Text Available The inhibition of butyrylcholinesterase (BChE, EC 3.1.1.8 appears to be of interest in treating diseases with symptoms of reduced neurotransmitter levels, such as Alzheimer’s disease. However, BCHE gene polymorphism should not be neglected in research since it could have an effect on the expected outcome. Several well-known cholinergic drugs (e.g. galantamine, huperzine and rivastigmine originating from plants, or synthesised as derivatives of plant compounds, have shown that herbs could serve as a source of novel target-directed compounds. We focused our research on flavonoids, biologically active polyphenolic compounds found in many plants and plant-derived products, as BChE inhibitors. All of the tested flavonoids: galangin, quercetin, fisetin and luteolin reversibly inhibited usual, atypical, and fluoride-resistant variants of human BChE. The inhibition potency increased in the following order, identically for all three BChE variants: luteolinflavonoids exists in view of BChE polymorphism. Our results suggested that flavonoids could assist the further development of new BChE-targeted drugs for treating symptoms of neurodegenerative diseases and dementia.

Flavonoid rutin increases thyroid iodide uptake in rats.

Directory of Open Access Journals (Sweden)

Carlos Frederico Lima Gonçalves

Full Text Available Thyroid iodide uptake through the sodium-iodide symporter (NIS is not only an essential step for thyroid hormones biosynthesis, but also fundamental for the diagnosis and treatment of different thyroid diseases. However, part of patients with thyroid cancer is refractory to radioiodine therapy, due to reduced ability to uptake iodide, which greatly reduces the chances of survival. Therefore, compounds able to increase thyroid iodide uptake are of great interest. It has been shown that some flavonoids are able to increase iodide uptake and NIS expression in vitro, however, data in vivo are lacking. Flavonoids are polyhydroxyphenolic compounds, found in vegetables present in human diet, and have been shown not only to modulate NIS, but also thyroperoxidase (TPO, the key enzyme in thyroid hormones biosynthesis, besides having antiproliferative effect in thyroid cancer cell lines. Therefore, we aimed to evaluate the effect of some flavonoids on thyroid iodide uptake in Wistar rats in vivo. Among the flavonoids tested, rutin was the only one able to increase thyroid iodide uptake, so we decided to evaluate the effect of this flavonoid on some aspects of thyroid hormones synthesis and metabolism. Rutin led to a slight reduction of serum T4 and T3 without changes in serum thyrotropin (TSH, and significantly increased hypothalamic, pituitary and brown adipose tissue type 2 deiodinase and decreased liver type 1 deiodinase activities. Moreover, rutin treatment increased thyroid iodide uptake probably due to the increment of NIS expression, which might be secondary to increased response to TSH, since TSH receptor expression was increased. Thus, rutin might be useful as an adjuvant in radioiodine therapy, since this flavonoid increased thyroid iodide uptake without greatly affecting thyroid function.

Extraction and Purification of Flavonoids from Radix Puerariae

African Journals Online (AJOL)

content of puerarin and flavonoids in the samples were tested by a HPLC and a UV-Vis. Spectrophotometer, respectively. ... the weight of the crude drug), the volume of loading sample is 2 BV (bed volume). The mobile phases of desorption are ... flavonoids, they have a variety of biological activities [1-3] including improving ...

Cocoa and chocolate flavonoids: implications for cardiovascular health.

Science.gov (United States)

Steinberg, Francene M; Bearden, Monica M; Keen, Carl L

2003-02-01

This paper offers a review of current scientific research regarding the potential cardiovascular health benefits of flavonoids found in cocoa and chocolate. Recent reports indicate that the main flavonoids found in cocoa, flavan-3-ols and their oligomeric derivatives, procyanidins, have a variety of beneficial actions, including antioxidant protection and modulation of vascular homeostasis. These findings are supported by similar research on other flavonoid-rich foods. Other constituents in cocoa and chocolate that may also influence cardiovascular health are briefly reviewed. The lipid content of chocolate is relatively high; however, one third of the lipid in cocoa butter is composed of the fat stearic acid, which exerts a neutral cholesterolemic response in humans. Cocoa and chocolate contribute to trace mineral intake, which is necessary for optimum functioning of all biologic systems and for vascular tone. Thus, multiple components in chocolate, particularly flavonoids, can contribute to the complex interplay of nutrition and health. Applications of this knowledge include recommendations by health professionals to encourage individuals to consume a wide range of phytochemical-rich foods, which can include dark chocolate in moderate amounts.

Foliar flavonoids from Tanacetum vulgare var. boreale and their geographical variation.

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Uehara, Ayumi; Akiyama, Shinobu; Iwashina, Tsukasa

2015-03-01

Foliar flavonoids of Tanacetum vulgare var. boreale were isolated. Eight flavonoid glycosides, 7-O-glucosides of apigenin, luteolin, scutellarein and 6- hydroxyluteolin, and 7-O-glucuronides of apigenin, luteolin, chrysoeriol and eriodictyol were identified. Moreover, eight flavonoid aglycones, apigenin, luteolin, hispidulin, nepetin, eupatilin, jaceosidin, pectolinarigenin and axillarin were also isolated and identified. The flavonoid composition of two varieties of T. vulgare, i.e. var. boreale and var. vulgare, were compared. All samples of var. boreale and one sample of var. vulgare had the same flavonoid pattern, and could be distinguished from almost all the samples of var. vulgare. Thus, the occurrence of chemotypes, which are characterized by either the presence or absence of scutellarein 7-O-glucoside, eriodictyol 7-O-glucuronide and pectolinarigenin was shown in T. vulgare sensu lato.

Methylation of flavonoids: Chemical structures, bioactivities, progress and perspectives for biotechnological production.

Science.gov (United States)

Koirala, Niranjan; Thuan, Nguyen Huy; Ghimire, Gopal Prasad; Thang, Duong Van; Sohng, Jae Kyung

2016-05-01

Among the natural products, flavonoids have been particularly attractive, highly studied and become one of the most important promising agent to treat cancer, oxidant stress, pathogenic bacteria, inflammations, cardio-vascular dysfunctions, etc. Despite many promising roles of flavonoids, expectations have not been fulfilled when studies were extended to the in vivo condition, particularly in humans. Instability and very low oral bioavailability of dietary flavonoids are the reasons behind this. Researches have demonstrated that the methylation of these flavonoids could increase their promise as pharmaceutical agents leading to novel applications. Methylation of the flavonoids via theirs free hydroxyl groups or C atom dramatically increases their metabolic stability and enhances the membrane transport, leading to facilitated absorption and highly increased oral bioavailability. In this paper, we concentrated on analysis of flavonoid methoxides including O- and C-methoxide derivatives in aspect of structure, bioactivities and description of almost all up-to-date O- and C-methyltransferases' enzymatic characteristics. Furthermore, modern biological approaches for synthesis and production of flavonoid methoxides using metabolic engineering and synthetic biology have been focused and updated up to 2015. This review will give a handful information regarding the methylation of flavonoids, methyltransferases and biotechnological synthesis of the same. Copyright © 2016 Elsevier Inc. All rights reserved.

Foliar flavonoids of nine species of Bauhinia

OpenAIRE

SALATINO, ANTONIO; BLATT, CECÍLIA T.T.; SANTOS, DÉBORAH Y.A.C. DOS; VAZ, ANGELA M.S.F.

1999-01-01

Foliar flavonoids of nine species of Bauhinia were isolated and identified. All the compounds correspond to glycosides derived from kaempferol, quercetin, isorhamnetin and myricetin. Derivatives of the latter aglyconhe seem to be rare in Bauhinia. Derivatives of isorhamnetin are commonly found in species of subgenus Bauhinia and were not detected in the two species of subgenus Phanera. Flavonoid patterns of species of the former subgenus are in general more complex than those of the latter. ...

Management of diabetic complications through fruit flavonoids as a natural remedy.

Science.gov (United States)

Tanveer, Amna; Akram, Kashif; Farooq, Umar; Hayat, Zafar; Shafi, Afshan

2017-05-03

Diabetes mellitus is a global disorder, and a major issue for health care systems. The current review outlooks the use of fruit flavonoids as natural remedy in the prevention of diabetes mellitus. The onset of diabetes mainly depends upon genetics and lifestyle issues. Currently used therapeutic options for the control of diabetes, like dietary amendments, oral hypoglycemic drugs, and insulin, have their own limitations. Fruit flavonoids possess various antidiabetic, anti-inflammatory, and antioxidant potentials and act on various cellular signaling pathways in pancreas, white adipose tissue, skeletal muscle, and liver function, which in result induces antidiabetic effects. Recently, antidiabetic effect of fruit flavonoids has been studied using various animal models and clinical trials. Research studies revealed a statistically significant potential of fruit flavonoids in managing the altered glucose and oxidative metabolisms in diabetes. Unlike synthetic antidiabetic agents, fruit flavonoids manage diabetes without compromising cellular homeostasis thereby posing no side effects. Further studies are required in purification and characterization of different fruit flavonoids with respect to their beneficial effect for diabetic patients.

Composition of flavonoids in fresh herbs and calculation of flavonoid intake by use of herbs in traditional Danish dishes

DEFF Research Database (Denmark)

Justesen, U.; Knuthsen, Pia

2001-01-01

, coriander, cress, dill, lemon balm, lovage, oregano, parsley, rosemary, sage, spearmint, tarragon, thyme, and watercress) were analysed by HPLC and mass spectrometry. Five major flavonoid aglycones were detected and quantified by HPLC after acid hydrolysis: apigenin, isorhamnetin, kaempferol, luteolin......Many herbs are known as excellent sources of natural antioxidants, and consumption of fresh herbs in the diet may therefore contribute to the daily antioxidant intake. The present study was performed in order to quantify flavonoids in commonly eaten fresh herbs. Fifteen fresh herbs (basil, chives......, and quercetin. The highest levels of flavonoids were found in parsley (510-630 mg apigenin /100 g), lovage (170 mg quercetin/100g), mint (18-100 mg apigenin/ 100 g), and dill (48-110 mg quercetin/100 g). Mass spectrometric detection, using atmospheric pressure chemical ionisation (APCI), was used to verify...

Metabolic engineering of yeast for fermentative production of flavonoids

DEFF Research Database (Denmark)

Rodriguez Prado, Edith Angelica; Strucko, Tomas; Stahlhut, Steen Gustav

2017-01-01

Yeast Saccharomyces cerevisiae was engineered for de novo production of six different flavonoids (naringenin, liquiritigenin, kaempferol, resokaempferol, quercetin, and fisetin) directly from glucose, without supplementation of expensive intermediates. This required reconstruction of long...... demonstrates the potential of flavonoid-producing yeast cell factories....

Common dietary flavonoids inhibit the growth of the intraerythrocytic malaria parasite

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Saliba Kevin J

2008-06-01

Full Text Available Abstract Background Flavonoids are abundant plant phenolic compounds. More than 6000 have been identified to date, and some have been shown to possess antiparasitic activity. Here we investigate the effects of a range of common dietary flavonoids on the growth of two strains of the human malaria parasite Plasmodium falciparum. Findings A chloroquine-sensitive (3D7 and a chloroquine-resistant (7G8 strain of P. falciparum were tested for in vitro susceptibility to a range of individual dietary flavonoids and flavonoid combinations. Parasite susceptibility was measured in 96-well plates over 96 h using a previously described [3H]hypoxanthine incorporation assay. Of the eleven flavonoids tested, eight showed antiplasmodial activity against the 3D7 strain (with IC50 values between 11 and 66 μM, and all showed activity against the 7G8 strain (with IC50 values between 12 and 76 μM. The most active compound against both strains was luteolin, with IC50 values of 11 ± 1 μM and 12 ± 1 μM for 3D7 and 7G8, respectively. Luteolin was found to prevent the progression of parasite growth beyond the young trophozoite stage, and did not affect parasite susceptibility to the antimalarial drugs chloroquine or artemisinin. Combining low concentrations of flavonoids was found to produce an apparent additive antiplasmodial effect. Conclusion Certain common dietary flavonoids inhibit the intraerythrocytic growth of the 3D7 and 7G8 strains of P. falciparum. Flavonoid combinations warrant further investigation as antiplasmodial agents.

Quantitative determination of sage-leaved rockrose (Cistus salviifolius flavonoids

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H. M. Elkaib

2017-01-01

Full Text Available The widespread use of bioflavonoids, due to their antimicrobial activity and antioxidant properties, necessitates their separate determination in a joint presence. It is noted that the total content of flavonoids, determined by different spectrophotometric methods in the same samples, differs and depends on the structure of the individual flavonoids that make up the samples. The paper presents the results of studies to determine the content of flavonoids in the fraction of the dry extract of shalfeeloid canthus (Cistus salviifolius, which has antimicrobial activity against bacteria of the genus Pseudomonas, which causes damage to protein-containing food products. Curing flavonoids by sequential extraction with aqueous alcohol solutions, filtering and dissolving the dry residue in isopropyl alcohol followed by passing through the gel layers. The following methods for the determination of flavonoids are considered: reaction with Folin-Chikalteu reagent (using quercetin as standard, reaction with aluminum chloride and 2,4-dinitrophenylhydrazine. When oxidized in alkaline medium by the Folin-Chikalteu reagent, which is the phospho-molybdotungstate heteropolycomplexes of flavonols, flavin-3-ol and flavones can be converted into quinoid compounds having absorption bands in the visible region of the spectrum. Only flavones and flavones having hydroxyl groups at positions 3 and 5 can interact with AlCl3. 2,4-dinitrophenylhydrazine only interacts with flavonols. The obtained calibration curves and structural formulas of flavonoids are given, which can be determined by the methods presented. It was found to contain flavonols 0.21 mg / mg, flavones 0.17 mg / mg and flavin-3-ol 0.06 mg/mg.

Spectrophotometric analysis of flavonoid-DNA binding interactions at physiological conditions

Science.gov (United States)

Janjua, Naveed Kausar; Siddiqa, Asima; Yaqub, Azra; Sabahat, Sana; Qureshi, Rumana; Haque, Sayed ul

2009-12-01

Mode of interactions of three flavonoids [morin (M), quercetin (Q), and rutin (R)] with chicken blood ds.DNA (ck.DNA) has been investigated spectrophotometrically at different temperatures including body temperature (310 K) and at two physiological pH values, i.e. 7.4 (human blood pH) and 4.7 (stomach pH). The binding constants, Kf, evaluated using Benesi-Hildebrand equation showed that the flavonoids bind effectively through intercalation at both pH values and body temperature. Quercetin, somehow, showed greater binding capabilities with DNA. The free energies of flavonoid-DNA complexes indicated the spontaneity of their binding. The order of binding constants of three flavonoids at both pH values were found to be Kf(Q) > Kf(R) > Kf(M) and at 310 K.

Study on the high flavonoids mutants of tartarian buckwheat by radiation induced

International Nuclear Information System (INIS)

Li Guozhu; Shen Huifang

2011-01-01

Three different varieties of tartarian buckwheat seeds (Chuanqiao 1 # , Yu-621 and KP9920) were irradiated with various doses (100∼500 Gy) of 60 Co-γ ray and sowed. Ten, eight and six high flavonoid tartary buckwheat mutants were selected from three parent materials respectively. The flavonoid content of three parent materials were 8.33%, 10.18% and 9.80%. The range of flavonoid content of high flavonoids mutants for three parent materials 11.37%∼14.91%, 10.67%∼12.46% and 11.32%∼12.95% respectively. Cluster analysis was also carried out based on the agronomic traits and flavonoid content in the 27 tartary buckwheat materials (24 mutants and 3 parent material) The 27 materials were classified into four clusters by cluster analysis based on the agronomic traits and were classified into 5 groups based on flavonoid content. (authors)

Quercetin: a versatile flavonoid

Directory of Open Access Journals (Sweden)

Dr. Deepak Kumar Rai

2007-07-01

Full Text Available Associative evidence from observational and intervention studies in human subjects shows that a diet including plant foods (particularly fruit and vegetables rich in antioxidants conveys health benefits. There is no evidence that any particular nutrient or class of bioactive substances makes a special contribution to these benefits. Flavonoids occur naturally in fruits, vegetables and beverages such as tea and wine. Quercetin is the major flavonoid which belongs to the class called flavonols. Quercetin is found in many common foods including apples, tea, onions, nuts, berries, cauliflower, cabbage and many other foods. Quercetin provides many health promoting benefits, including improvement of cardiovascular health, eye diseases, allergic disorders, arthritis, reducing risk for cancers and many more. The main aim of this review is to obtain a further understanding of the reported beneficial health effects of Quercetin, its pharmacological effects, clinical application and also to evaluate its safety.

Flavonoids patterns of French honeys with different floral origin

NARCIS (Netherlands)

Soler, C.; Gil, M.I.; Garcia-Viguera, C.; Tomás-Barberán, F.A.

1995-01-01

The flavonoid profiles of 12 different unifloral French honey samples were analysed by HPLC to evaluate if these substances could be used as markers of the floral origin of honey. In this analysis, the characteristic flavonoids from propolis and/or beeswax (chrysin, galangin, tectochrysin,

Quantification and antibacterial activity of flavonoids in coffee samples

African Journals Online (AJOL)

Background: Flavonoids are the phenolic substances widely found in fruits, vegetables, grains, bark, roots, stems, flowers, tea and coffee. Methodology: In the current study quantity of flavonoids and antibacterial activities were determined in different coffee samples namely Nescafe classic, Nescafe gold, Nescafe martina, ...

Flavonoids, Thyroid Iodide Uptake and Thyroid Cancer-A Review.

Science.gov (United States)

Gonçalves, Carlos F L; de Freitas, Mariana L; Ferreira, Andrea C F

2017-06-12

Thyroid cancer is the most common malignant tumor of the endocrine system and the incidence has been increasing in recent years. In a great part of the differentiated carcinomas, thyrocytes are capable of uptaking iodide. In these cases, the main therapeutic approach includes thyroidectomy followed by ablative therapy with radioiodine. However, in part of the patients, the capacity to concentrate iodide is lost due to down-regulation of the sodium-iodide symporter (NIS), the protein responsible for transporting iodide into the thyrocytes. Thus, therapy with radioiodide becomes ineffective, limiting therapeutic options and reducing the life expectancy of the patient. Excessive ingestion of some flavonoids has been associated with thyroid dysfunction and goiter. Nevertheless, studies have shown that some flavonoids can be beneficial for thyroid cancer, by reducing cell proliferation and increasing cell death, besides increasing NIS mRNA levels and iodide uptake. Recent data show that the flavonoids apingenin and rutin are capable of increasing NIS function and expression in vivo. Herein we review literature data regarding the effect of flavonoids on thyroid cancer, besides the effect of these compounds on the expression and function of the sodium-iodide symporter. We will also discuss the possibility of using flavonoids as adjuvants for therapy of thyroid cancer.

Chlorinated Flavonoids Modulate the Inflammatory Process in Human Blood.

Science.gov (United States)

Proença, Carina; Ribeiro, Daniela; Soares, Tânia; Tomé, Sara M; Silva, Artur M S; Lima, José L F C; Fernandes, Eduarda; Freitas, Marisa

2017-08-01

Flavonoids are known to react with neutrophil-generated hypochlorous acid (HOCl) at inflammation loci to form stable mono- and dichlorinated products. Some of these products have been shown to retain or even enhance their inflammatory potential, but further information is required in a broader approach to inflammatory mechanisms. In that sense, we performed an integrated evaluation on the anti-inflammatory potential of a panel of novel chlorinated flavonoids and their parent compounds, in several steps of the complex inflammatory cascade, namely, in the activity of cyclooxygenase (COX)-1 and COX-2, and in the production of cytokines [interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)], and the chemokine, IL-8, as well as in the production of reactive species, using human whole blood as a representative in vitro model, establishing, whenever possible, a structure-activity relationship. Although luteolin was the most active compound, chlorinated flavonoids demonstrated a remarkable pattern of activity for the resolution of the inflammatory processes. Our results demonstrated that 6-chloro-3',4',5,7-tetrahydroxyflavone deserves scientific attention due to its ability to modulate the reactive species and cytokines/chemokine production. In this regard, the therapeutic potential of flavonoids' metabolites, and in this particular case the chlorinated flavonoids, should not be neglected.

Flavonoids, Thyroid Iodide Uptake and Thyroid Cancer—A Review

Science.gov (United States)

Gonçalves, Carlos F. L.; de Freitas, Mariana L.; Ferreira, Andrea C. F.

2017-01-01

Thyroid cancer is the most common malignant tumor of the endocrine system and the incidence has been increasing in recent years. In a great part of the differentiated carcinomas, thyrocytes are capable of uptaking iodide. In these cases, the main therapeutic approach includes thyroidectomy followed by ablative therapy with radioiodine. However, in part of the patients, the capacity to concentrate iodide is lost due to down-regulation of the sodium-iodide symporter (NIS), the protein responsible for transporting iodide into the thyrocytes. Thus, therapy with radioiodide becomes ineffective, limiting therapeutic options and reducing the life expectancy of the patient. Excessive ingestion of some flavonoids has been associated with thyroid dysfunction and goiter. Nevertheless, studies have shown that some flavonoids can be beneficial for thyroid cancer, by reducing cell proliferation and increasing cell death, besides increasing NIS mRNA levels and iodide uptake. Recent data show that the flavonoids apingenin and rutin are capable of increasing NIS function and expression in vivo. Herein we review literature data regarding the effect of flavonoids on thyroid cancer, besides the effect of these compounds on the expression and function of the sodium-iodide symporter. We will also discuss the possibility of using flavonoids as adjuvants for therapy of thyroid cancer. PMID:28604619

Flavonoids – Small Molecules, High Hopes

Directory of Open Access Journals (Sweden)

Sandu Mariana

2017-07-01

Full Text Available This brief review takes a look at flavonoids, a wide class of polyphenols, which are regarded as plant secondary metabolites. Their roles in plants are diverse and little understood. They can act as growth hormone modulators, phytoalexins, they offer UV protection, contribute to pollen viability and can function as signaling molecules in establishing symbiotic relationships. Flavonoids were also found to have a range of beneficial effects for the human body. Their anticancer, antioxidant, anti-inflammatory and cardioprotective activity, as well as their antibacterial, antiviral and antihelmintic properties make them promising candidates for the design of new drugs.

Buckwheat seedling flavonoids do not undergo rapid turnover

International Nuclear Information System (INIS)

Margna, U.; Vainjaerv, T.

1981-01-01

Pulse-labelling with exogenous [1- 14 C]-L-phenylalanine showed that of all flavonoids of buckwheat seedling cotyledons only anthocyanins underwent a slow turnover (not more than 6-8 per cent a day) whilst the major flavonoids, rutin and four C-glycosylflavones, remained metabolically stable within at least 7 days. From excised hypocotyls pulse-labelled flavonoids (anthocyanins and rutin) began to disappear gradually beginning with the second day of incubation. As hypocotyls, however, during prolonged incubation soon began to autolyse a considerable part of that loss was obviously due to abnormal shifts in cell metabolic activities with a possibility that some microbial process was also involved. In hypocotyls of intact seedlings pulse-labelled rutin, similar to rutin in cotyledons, showed no signs of turnover. (author)

Flavonoids and thyroid disease

NARCIS (Netherlands)

Heide, van der D.; Kastelijn, J.; Schroder-van der Elst, J.P.

2003-01-01

The most potent natural plant-derived compounds that can affect thyroid function, thyroid hormone secretion and availability to tissues is the group of flavonoids, i.e. plant pigments. They are present in our daily food, such as vegetables, fruits, grains, nuts, wine, and tea. Epidemiological

Isolation and Antimicrobial Activity of Flavonoid Compounds from Mahagony Seeds (Swietenia macrophylla, King)

Science.gov (United States)

Mursiti, S.; Supartono

2017-02-01

Flavonoid is one of the secondary metabolites compounds in mahogany seeds. Mahogany seeds can be used as an antimicrobial. This study aims to determine the antimicrobial activity of flavonoid compounds from mahogany seeds against Escherichia coli (E.coli) and Bacillus cereus (B.cereus). Isolation of flavonoid compounds done step by step. First, the maceration using n-hexane, then with methanol. The methanol extract was dissolved in ethyl acetate and aquadest, then separated. Ethyl acetate extract evaporated Flavonoid compounds were. The testing of antimicrobial activity of flavonoid compounds using the absorption method. The results showed that the antimicrobial activity of flavonoid compounds from mahogany seeds shows the inhibitory activity and provide clear zone against bacteria E.coli with value Inhibitory Regional Diameter 18.50 mm respectively, and 14.50 mm to the bacteria. Based on the results of the study, it can be concluded that flavonoid compounds from mahogany seeds have antimicrobial activity against E.coli and B.cereus.

Effect of citrus flavonoids on HL-60 cell differentiation.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

1999-01-01

Twenty-seven Citrus flavonoids were examined for their activity of induction of terminal differentiation of human promyelocytic leukemia cells (HL-60) by nitro blue tetrazolium (NBT) reducing, nonspecific esterase, specific esterase, and phagocytic activities. 10 flavonoids were judged to be active (percentage of NBT reducing cells was more than 40% at a concentration of 40 microM), and the rank order of potency was natsudaidain, luteolin, tangeretin, quercetin, apigenin, 3, 3, '4, '5, 6, 7, 8-heptamethoxyflavone, nobiletin, acacetin, eriodictyol, and taxifolin. These flavonoids exerted their activity in a dose-dependent manner. HL-60 cells treated with these flavonoids differentiated into mature monocyte/macrophage. The structure-activity relationship established from comparison between flavones and flavanones revealed that ortho-catechol moiety in ring B and C2-C3 double bond had an important role for induction of differentiation of HL-60. In polymethoxylated flavones, hydroxyl group at C3 and methoxyl group at C8 enhanced the differentiation-inducing activity.

Flavonoids protecting food and beverages against light.

Science.gov (United States)

Huvaere, Kevin; Skibsted, Leif H

2015-01-01

Flavonoids, which are ubiquitously present in the plant kingdom, preserve food and beverages at the parts per million level with minor perturbation of sensory impressions. Additionally, they are safe and possibly contribute positive health effects. Flavonoids should be further exploited for the protection of food and beverages against light-induced quality deterioration through: (1) direct absorption of photons as inner filters protecting sensitive food components; (2) deactivation of (triplet-)excited states of sensitisers like chlorophyll and riboflavin; (3) quenching of singlet oxygen from type II photosensitisation; and (iv) scavenging of radicals formed as reaction intermediates in type I photosensitisation. For absorption of light, combinations of flavonoids, as found in natural co-pigmentation, facilitate dissipation of photon energy to heat thus averting photodegradation. For protection against singlet oxygen and triplet sensitisers, chemical quenching gradually decreases efficiency hence the pathway to physical quenching should be optimised through product formulation. The feasibility of these protection strategies is further supported by kinetic data that are becoming available, allowing for calculation of threshold levels of flavonoids to prevent beer and dairy products from going off. On the other hand, increasing understanding of the interplay between light and matrix physicochemistry, for example the effect of aprotic microenvironments on phototautomerisation of compounds like quercetin, opens up for engineering better light-to-heat converting channels in processed food to eventually prevent quality loss. © 2014 Society of Chemical Industry.

A chalcone isomerase-like protein enhances flavonoid production and flower pigmentation.

Science.gov (United States)

Morita, Yasumasa; Takagi, Kyoko; Fukuchi-Mizutani, Masako; Ishiguro, Kanako; Tanaka, Yoshikazu; Nitasaka, Eiji; Nakayama, Masayoshi; Saito, Norio; Kagami, Takashi; Hoshino, Atsushi; Iida, Shigeru

2014-04-01

Flavonoids are major pigments in plants, and their biosynthetic pathway is one of the best-studied metabolic pathways. Here we have identified three mutations within a gene that result in pale-colored flowers in the Japanese morning glory (Ipomoea nil). As the mutations lead to a reduction of the colorless flavonoid compound flavonol as well as of anthocyanins in the flower petal, the identified gene was designated enhancer of flavonoid production (EFP). EFP encodes a chalcone isomerase (CHI)-related protein classified as a type IV CHI protein. CHI is the second committed enzyme of the flavonoid biosynthetic pathway, but type IV CHI proteins are thought to lack CHI enzymatic activity, and their functions remain unknown. The spatio-temporal expression of EFP and structural genes encoding enzymes that produce flavonoids is very similar. Expression of both EFP and the structural genes is coordinately promoted by genes encoding R2R3-MYB and WD40 family proteins. The EFP gene is widely distributed in land plants, and RNAi knockdown mutants of the EFP homologs in petunia (Petunia hybrida) and torenia (Torenia hybrida) had pale-colored flowers and low amounts of anthocyanins. The flavonol and flavone contents in the knockdown petunia and torenia flowers, respectively, were also significantly decreased, suggesting that the EFP protein contributes in early step(s) of the flavonoid biosynthetic pathway to ensure production of flavonoid compounds. From these results, we conclude that EFP is an enhancer of flavonoid production and flower pigmentation, and its function is conserved among diverse land plant species. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

Dietary flavonoid intake at midlife and healthy aging in women.

Science.gov (United States)

Samieri, Cécilia; Sun, Qi; Townsend, Mary K; Rimm, Eric B; Grodstein, Francine

2014-12-01

Dietary flavonoids have been related to lower risks of various chronic diseases, but it is unclear whether flavonoid intake in midlife helps to maintain good health and wellbeing in aging. We examined the relation of flavonoid intake in midlife with the prevalence of healthy aging. We included 13,818 women from the Nurses' Health Study with dietary data and no major chronic diseases in 1984-1986 when they were aged in their late 50s (median age: 59 y); all women provided information on multiple aspects of aging an average of 15 y later. Intakes of 6 major flavonoid subclasses in midlife were ascertained on the basis of averaged intakes of flavonoid-rich foods from 2 food-frequency questionnaires (1984-1986). We defined healthy compared with usual aging as of age 70 y; healthy aging was based on survival to ≥70 y with maintenance of 4 health domains (no major chronic diseases or major impairments in cognitive or physical function or mental health). Of women who survived until ≥70 y of age, 1517 women (11.0%) met our criteria for healthy aging. Compared with women in the lowest quintile of intake, women in the highest quintile of intake of several flavonoid subclasses at midlife had greater odds of healthy aging. After multivariable adjustment, ORs were as follows: flavones, 1.32 (95% CI: 1.10, 1.58); flavanone, 1.28 (95% CI: 1.08, 1.53); anthocyanin, 1.25 (95% CI: 1.04, 1.50); and flavonol, 1.18 (95% CI: 0.98, 1.42) (all P-trend ≤ 0.02). Consistently, greater intakes of major sources of these flavonoids (i.e., oranges, berries, onions, and apples) were associated with increased odds of healthy aging. We showed no association with flavan-3-ol monomers (P-trend = 0.80) or polymers (P-trend = 0.63). Higher intake of flavonoids at midlife, specifically flavones, flavanones, anthocyanins, and flavonols, is associated with greater likelihood of health and wellbeing in individuals surviving to older ages. © 2014 American Society for Nutrition.

Antioxidant Activities and Chemical Constituents of Flavonoids from the Flower of Paeonia ostii.

Science.gov (United States)

Zhang, Huifang; Li, Xiaofang; Wu, Ke; Wang, Mengke; Liu, Pu; Wang, Xinsheng; Deng, Ruixue

2016-12-23

Paeonia ostii is a traditional medicinal plant popularly used in China. This study intended to evaluate the antioxidant properties and the chemical components of the flavonoid-rich extracts from the flowers of P. ostii . The results showed that the flavonoid-rich extracts from the flowers of P. ostii had strong scavenging capacities on 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS), hydroxyls, superoxide anions, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals in a dose-dependent manner. Five flavonoids, dihydrokaempferol ( 1 ), apigenin-7- O -β-d-glucoside ( 2 ), apigenin-7- O -β-d-neohesperidoside ( 3 ), kaempferol-7- O -β-d-glucopyranoside ( 4 ), and kaempferol-3- O -β-d-glucopyranosyl-7- O -β-d-glucopyranoside ( 5 ), were isolated from the flavonoid-rich extracts of the flowers of P. ostii . High-performance liquid chromatography (HPLC) analysis revealed that compounds 3 and 4 were abundant in the P. ostii flower and in flavonoid-rich extracts. The main components of the flower of P. ostii are flavonoids. The high antioxidant activity of the flavonoid-rich extracts may be attributed to the high content of flavonoids. The five isolated flavonoids were the primary antioxidant ingredients, and may play important roles in the strong antioxidant activities of this flower. Based on the obtained results, the flower of P. ostii could be a potential source of natural antioxidants in food and pharmaceutical applications.

[MapDraw: a microsoft excel macro for drawing genetic linkage maps based on given genetic linkage data].

Science.gov (United States)

Liu, Ren-Hu; Meng, Jin-Ling

2003-05-01

MAPMAKER is one of the most widely used computer software package for constructing genetic linkage maps.However, the PC version, MAPMAKER 3.0 for PC, could not draw the genetic linkage maps that its Macintosh version, MAPMAKER 3.0 for Macintosh,was able to do. Especially in recent years, Macintosh computer is much less popular than PC. Most of the geneticists use PC to analyze their genetic linkage data. So a new computer software to draw the same genetic linkage maps on PC as the MAPMAKER for Macintosh to do on Macintosh has been crying for. Microsoft Excel,one component of Microsoft Office package, is one of the most popular software in laboratory data processing. Microsoft Visual Basic for Applications (VBA) is one of the most powerful functions of Microsoft Excel. Using this program language, we can take creative control of Excel, including genetic linkage map construction, automatic data processing and more. In this paper, a Microsoft Excel macro called MapDraw is constructed to draw genetic linkage maps on PC computer based on given genetic linkage data. Use this software,you can freely construct beautiful genetic linkage map in Excel and freely edit and copy it to Word or other application. This software is just an Excel format file. You can freely copy it from ftp://211.69.140.177 or ftp://brassica.hzau.edu.cn and the source code can be found in Excel's Visual Basic Editor.

From Enclave to Linkage Economies?

DEFF Research Database (Denmark)

Hansen, Michael W.

as the enclave economy par excellence, moving in with fully integrated value chains, extracting resources and exporting them as commodities having virtually no linkages to the local economy. However, new opportunities for promoting linkages are offered by changing business strategies of local African enterprises...... as well as foreign multinational corporations (MNCs). MNCs in extractives are increasingly seeking local linkages as part of their efficiency, risk, and asset-seeking strategies, and linkage programmes are becoming integral elements in many MNCs’ corporate social responsibility (CSR) activities....... At the same time, local African enterprises are eager to, and increasingly capable of, linking up to the foreign investors in order to expand their activities and acquire technology, skills and market access. The changing strategies of MNCs and the improving capabilities of African enterprises offer new...

Flavonoid Functions in Plants and Their Interactions with Other Organisms

Directory of Open Access Journals (Sweden)

Ulrike Mathesius

2018-04-01

Full Text Available Flavonoids are structurally diverse secondary metabolites in plants, with a multitude of functions. These span from functions in regulating plant development, pigmentation, and UV protection, to an array of roles in defence and signalling between plants and microorganisms. Because of their prevalence in the human diet, many flavonoids constitute important components of medicinal plants and are used in the control of inflammation and cancer prevention. Advances in the elucidation of flavonoid biosynthesis and its regulation have led to an increasing number of studies aimed at engineering the flavonoid pathway for enhancing nutritional value and plant defences against pathogens and herbivores, as well as modifying the feeding value of pastures. Many future opportunities await for the exploitation of this colourful pathway in crops, pastures, and medicinal plants.

Brosimacutins A-I, nine new flavonoids from Brosimum acutifolium.

Science.gov (United States)

Takashima, Junko; Ohsaki, Ayumi

2002-12-01

Nine new flavonoids, brosimacutins A-I (1-9), and four known flavonoids were isolated from the bark of Brosimum acutifolium, a Brazilian folk medicine ("Mururé"). Their structures were elucidated by spectroscopic methods, including 2D NMR. Brosimacutins A-I possess differentially functionalized isoprene units at C-8.

Automated Annotation of Microbial and Human Flavonoid-Derived Metabolites

NARCIS (Netherlands)

Mihaleva, V.V.; Ünlü, F.; Vervoort, J.J.M.; Ridder, L.O.

2015-01-01

Flavonoids are a class of natural compounds essentially produced by plants that are part of animal and human diets and have assumed health-promoting benefits. Upon human consumption, these flavonoids are to a modest extent absorbed in the small intestines. The major part arrives in the colon where

Quantification of Tea Flavonoids by High Performance Liquid Chromatography

Science.gov (United States)

Freeman, Jessica D.; Niemeyer, Emily D.

2008-01-01

We have developed a laboratory experiment that uses high performance liquid chromatography (HPLC) to quantify flavonoid levels in a variety of commercial teas. Specifically, this experiment analyzes a group of flavonoids known as catechins, plant-derived polyphenolic compounds commonly found in many foods and beverages, including green and black…

Antibacterial, anti-inflammatory and diuretic effect of flavonoids from ...

African Journals Online (AJOL)

Dried leaves of Marchantia convoluta are largely used to protect livers, and to treat tumefaction of skins in China. Flavonoids from Marchantia convoluta (MCF) were the active components against hepatitis B virus. In this study, the pharmacological properties of MCF consisting of flavonoids determined by HPLC were ...

Total flavonoid concentrations of bryophytes from Tianmu Mountain, Zhejiang Province (China: Phylogeny and ecological factors.

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Xin Wang

Full Text Available The flavonoids in bryophytes may have great significance in phylogeny and metabolism research. However, to date there has been little research on bryophyte metabolites, especially flavonoids. To redress this somewhat, we determined flavonoid concentrations of bryophytes from Tianmu Mountain through a colorimetric assay and considered the factors influencing the results. This is the first time that the flavonoid contents of bryophytes have been examined in detail. The results revealed a range of total flavonoid concentrations in 90 samples collected from Tianmu Mountain from 1.8 to 22.3 mg/g (w/w. The total flavonoid contents of liverworts were generally higher than those of mosses; acrocarpous mosses had generally higher values than that of pleurocarpous mosses. The total flavonoid contents of bryophytes growing at lower light levels were general higher than those growing in full-sun. The total flavonoid contents of epiphytic bryophytes were highest, while those of aquatic bryophytes were the lowest. Total flavonoid contents of species growing at low-latitudes were much higher than those at high-latitude individuals. In conclusion, total flavonoid contents of bryophytes have some connection with plant phylogeny; more flavonoids might be contained in relatively primitive bryophytes. Meanwhile, the effects of ecological factors on total flavonoid contents of bryophytes exist; light and habitat (especially tree habitat and river habitat might be representative factor.

Impact of Plant-Derived Flavonoids on Neurodegenerative Diseases.

Science.gov (United States)

Costa, Silvia Lima; Silva, Victor Diogenes Amaral; Dos Santos Souza, Cleide; Santos, Cleonice Creusa; Paris, Irmgard; Muñoz, Patricia; Segura-Aguilar, Juan

2016-07-01

Neurodegenerative disorders have a common characteristic that is the involvement of different cell types, typically the reactivity of astrocytes and microglia, characterizing gliosis, which in turn contributes to the neuronal dysfunction and or death. Flavonoids are secondary metabolites of plant origin widely investigated at present and represent one of the most important and diversified among natural products phenolic groups. Several biological activities are attributed to this class of polyphenols, such as antitumor activity, antioxidant, antiviral, and anti-inflammatory, among others, which give significant pharmacological importance. Our group have observed that flavonoids derived from Brazilian plants Dimorphandra mollis Bent., Croton betulaster Müll. Arg., e Poincianella pyramidalis Tul., botanical synonymous Caesalpinia pyramidalis Tul. also elicit a broad spectrum of responses in astrocytes and neurons in culture as activation of astrocytes and microglia, astrocyte associated protection of neuronal progenitor cells, neuronal differentiation and neuritogenesis. It was observed the flavonoids also induced neuronal differentiation of mouse embryonic stem cells and human pluripotent stem cells. Moreover, with the objective of seeking preclinical pharmacological evidence of these molecules, in order to assess its future use in the treatment of neurodegenerative disorders, we have evaluated the effects of flavonoids in preclinical in vitro models of neuroinflammation associated with Parkinson's disease and glutamate toxicity associated with ischemia. In particular, our efforts have been directed to identify mechanisms involved in the changes in viability, morphology, and glial cell function induced by flavonoids in cultures of glial cells and neuronal cells alone or in interactions and clarify the relation with their neuroprotective and morphogetic effects.

Preparative Separation and Purification of the Total Flavonoids in Scorzonera austriaca with Macroporous Resins.

Science.gov (United States)

Xie, Yang; Guo, Qiu-Shi; Wang, Guang-Shu

2016-06-13

The use of macroporous resins for the separation and purification of total flavonoids to obtain high-purity total flavonoids from Scorzonera austriaca was studied. The optimal conditions for separation and purification of total flavonoids in S. austriaca with macroporous resins were as follows: D4020 resin columns were loaded with crude flavonoid extract solution, and after reaching adsorptive saturation, the columns were eluted successively with 5 bed volumes (BV) of water, 5 BV of 5% (v/v) aqueous ethanol and 5 BV of 30% (v/v) aqueous ethanol at an elute flow rate of 2 BV·h(-1). Total flavonoids were obtained from the 30% aqueous ethanol eluate by vacuum distillation recovery. The content of flavonoid compounds in the total flavonoids was 93.5%, which represents an improvement by about 150%. In addition, five flavonoid compounds in the product were identified as 2″-O-β-d-xylopyranosyl isoorientin, 6-C-α-l-arabipyranosyl orientin, orientin, isoorientin and vitexin by LC-ESI-MS analysis and internal standard methods. The results in this study could represent a method for the large-scale production of total flavonoids from S. austriaca.

Flavonoid intake and cardiovascular disease mortality in a prospective cohort of US adults

Science.gov (United States)

Background: Flavonoids are plant-based phytochemicals with cardiovascular protective properties. Few studies have comprehensively examined flavonoid classes in relation to cardiovascular disease mortality. We examined the association between flavonoid intake and cardiovascular disease (CVD) mortalit...

Challenges in administrative data linkage for research

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Katie Harron

2017-12-01

Full Text Available Linkage of population-based administrative data is a valuable tool for combining detailed individual-level information from different sources for research. While not a substitute for classical studies based on primary data collection, analyses of linked administrative data can answer questions that require large sample sizes or detailed data on hard-to-reach populations, and generate evidence with a high level of external validity and applicability for policy making. There are unique challenges in the appropriate research use of linked administrative data, for example with respect to bias from linkage errors where records cannot be linked or are linked together incorrectly. For confidentiality and other reasons, the separation of data linkage processes and analysis of linked data is generally regarded as best practice. However, the ‘black box’ of data linkage can make it difficult for researchers to judge the reliability of the resulting linked data for their required purposes. This article aims to provide an overview of challenges in linking administrative data for research. We aim to increase understanding of the implications of (i the data linkage environment and privacy preservation; (ii the linkage process itself (including data preparation, and deterministic and probabilistic linkage methods and (iii linkage quality and potential bias in linked data. We draw on examples from a number of countries to illustrate a range of approaches for data linkage in different contexts.

Flavonoids: A Metabolic Network Mediating Plants Adaptation to Their Real Estate

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Aidyn eMouradov

2014-11-01

Full Text Available From an evolutionary perspective, the emergence of the sophisticated chemical scaffolds of flavonoid molecules represents a key step in the colonization of Earth’s terrestrial environment by vascular plants nearly 500 million years ago. The subsequent evolution of flavonoids through recruitment and modification of ancestors involved in primary metabolism has allowed vascular plants to cope with pathogen invasion and damaging UV light. The functional properties of flavonoids as a unique combination of different classes of compounds vary significantly depending on the demands of their local real estate. Apart from geographical location, the composition of flavonoids is largely dependent on the plant species, their developmental stage, tissue type, subcellular localization, and key ecological influences of both biotic and abiotic origin. Molecular and metabolic cross-talk between flavonoid and other pathways as a result of the re-direction of intermediate molecules have been well investigated. This metabolic plasticity is a key factor in plant adaptive strength and is of paramount importance for early land plants adaptation to their local ecosystems. In human and animal health the biological and pharmacological activities of flavonoids have been investigated in great depth and have shown a wide range of anti-inflammatory, anti-oxidant, anti-microbial and anti-cancer properties. In this paper we review the application of advanced gene technologies for targeted reprogramming of the flavonoid pathway in plants to understand its molecular functions and explore opportunities for major improvements in forage plants enhancing animal health and production.

Flavonoids: a metabolic network mediating plants adaptation to their real estate.

Science.gov (United States)

Mouradov, Aidyn; Spangenberg, German

2014-01-01

From an evolutionary perspective, the emergence of the sophisticated chemical scaffolds of flavonoid molecules represents a key step in the colonization of Earth's terrestrial environment by vascular plants nearly 500 million years ago. The subsequent evolution of flavonoids through recruitment and modification of ancestors involved in primary metabolism has allowed vascular plants to cope with pathogen invasion and damaging UV light. The functional properties of flavonoids as a unique combination of different classes of compounds vary significantly depending on the demands of their local real estate. Apart from geographical location, the composition of flavonoids is largely dependent on the plant species, their developmental stage, tissue type, subcellular localization, and key ecological influences of both biotic and abiotic origin. Molecular and metabolic cross-talk between flavonoid and other pathways as a result of the re-direction of intermediate molecules have been well investigated. This metabolic plasticity is a key factor in plant adaptive strength and is of paramount importance for early land plants adaptation to their local ecosystems. In human and animal health the biological and pharmacological activities of flavonoids have been investigated in great depth and have shown a wide range of anti-inflammatory, anti-oxidant, anti-microbial, and anti-cancer properties. In this paper we review the application of advanced gene technologies for targeted reprogramming of the flavonoid pathway in plants to understand its molecular functions and explore opportunities for major improvements in forage plants enhancing animal health and production.

Flavonoids in Inflammatory Bowel Disease: A Review

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Teresa Vezza

2016-04-01

Full Text Available Inflammatory bowel disease (IBD is characterized by chronic inflammation of the intestine that compromises the patients’ life quality and requires sustained pharmacological and surgical treatments. Since their etiology is not completely understood, non-fully-efficient drugs have been developed and those that have shown effectiveness are not devoid of quite important adverse effects that impair their long-term use. In this regard, a growing body of evidence confirms the health benefits of flavonoids. Flavonoids are compounds with low molecular weight that are widely distributed throughout the vegetable kingdom, including in edible plants. They may be of great utility in conditions of acute or chronic intestinal inflammation through different mechanisms including protection against oxidative stress, and preservation of epithelial barrier function and immunomodulatory properties in the gut. In this review we have revised the main flavonoid classes that have been assessed in different experimental models of colitis as well as the proposed mechanisms that support their beneficial effects.

Flavonoids in Inflammatory Bowel Disease: A Review

Science.gov (United States)

Vezza, Teresa; Rodríguez-Nogales, Alba; Algieri, Francesca; Utrilla, Maria Pilar; Rodriguez-Cabezas, Maria Elena; Galvez, Julio

2016-01-01

Inflammatory bowel disease (IBD) is characterized by chronic inflammation of the intestine that compromises the patients’ life quality and requires sustained pharmacological and surgical treatments. Since their etiology is not completely understood, non-fully-efficient drugs have been developed and those that have shown effectiveness are not devoid of quite important adverse effects that impair their long-term use. In this regard, a growing body of evidence confirms the health benefits of flavonoids. Flavonoids are compounds with low molecular weight that are widely distributed throughout the vegetable kingdom, including in edible plants. They may be of great utility in conditions of acute or chronic intestinal inflammation through different mechanisms including protection against oxidative stress, and preservation of epithelial barrier function and immunomodulatory properties in the gut. In this review we have revised the main flavonoid classes that have been assessed in different experimental models of colitis as well as the proposed mechanisms that support their beneficial effects. PMID:27070642

Changes in flavonoid content of grapefruit juice caused by thermal treatment and storage

OpenAIRE

Igual Ramo, Marta; García Martínez, Eva María; Camacho Vidal, Mª Mar; Martínez Navarrete, Nuria

2011-01-01

The effect of conventional and microwave pasteurization on the main flavonoids present in grapefruit juice and their stability throughout 2 months of refrigerated and frozen storage was evaluated. Individual flavonoids were analyzed by HPLC. The results showed that naringin, narirutin, quercetin and naringenin were the most abundant flavonoids in grapefruit juice. In general, although every pasteurization treatment caused a significant reduction in the content of all the studied flavonoids, t...

Antioxidant and Hepatoprotective Activities of Flavonoids from Bauhinia hookeri

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Eman Al-Sayed

2016-05-01

Full Text Available In a previous study, the total ethanol extract of Bauhinia hookeri showed a significant hepatoprotective effect in CCl 4-induced toxicity model in mice. However, the active components responsible for the activity were not identified. Therefore, this study was undertaken to determine if the activity of B. hookeri extract is due to its flavonoid content. The hepatoprotective activity of B. hookeri flavonoids was determined by measuring the activities of alanine aminotransferase (ALT and aspartate aminotransferase (AST in the culture medium of HepG2 cells challenged with CCl 4. The lipid peroxidation and antioxidant parameters, superoxide dismutase (SOD and glutathione (GSH were estimated in the cell lysates. The isolated flavonoids were identified by mass, UV and NMR spectral data. This study revealed that B. hookeri flavonoid fraction and its pure compounds ( kaempferol 3-O-β- D-glucoside, quercetin 3-O-β- D-glucoside and c atechin 3-O-α- L-rhamnoside possess a promising hepatoprotective activity as evidenced from the normalized levels of ALT and AST. This was attributed partly to their potent antioxidant activity as demonstrated by the increased GSH levels, SOD activity and reduced lipid peroxidation. The whole flavonoid fraction showed the highest cytoprotective activity and was more effective than silymarin. This study highlights a promising natural hepatoprotective remedy derived from B. hookeri.

Non-alcoholic Fatty Liver Disease: Beneficial Effects of Flavonoids.

Science.gov (United States)

Akhlaghi, Masoumeh

2016-10-01

Non-alcoholic fatty liver disease (NAFLD) has been known as the hepatic feature of metabolic syndrome. Extra fat depots, especially in visceral areas, develop insulin resistance as a result of mild oxidation and inflammation. Insulin resistance induces lipolysis and releases free fatty acids into the circulation, where they are transported to the liver. In the liver, free fatty acids are converted to triglycerides and accumulate, causing simple steatosis that, if left untreated, can lead to steatohepatitis, and subsequently liver necrosis and cirrhosis.Flavonoids, a group of plant compounds with incredible biological characteristics, have shown advantages in pathological conditions. Beneficial effects of flavonoids against NAFLD and its related disorders have been observed in both animal and human studies. Various mechanisms have been found for their protection. Flavonoids prevent hepatosteatosis by increasing fatty acid oxidation in the liver. They can also reduce caloric intake and decrease body weight and fat deposition in visceral tissues. Flavonoids are unique antioxidants that exert their beneficial effects through inhibition of nuclear factor κB, thereby attenuating release of inflammatory cytokines, which are triggers of insulin resistance. Finally, flavonoids have shown to increase adiponectin, improve insulin sensitivity and glucose tolerance, correct dyslipidemia, and reduce blood pressure in patients with NAFLD. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Protective effects of flavonoids from corn silk on oxidative stress ...

African Journals Online (AJOL)

Protective effects of flavonoids from corn silk on oxidative stress induced by ... The present study aims at exploring the effects of flavonoids from corn silk (FCS) on oxidative stress induced by exhaustive exercise in mice. ... from 32 Countries:.

Phytochemical studies of flavonoids from polygonum glabrum L of Sudan

Energy Technology Data Exchange (ETDEWEB)

Mohammed, Intisar Sirour [Faculty of Science, University of Khartoum, Khartoum (Sudan)

1996-01-01

A semi- aquatic plant, Polygnum glabrum wild of the family polygonaceae was reported in traditional medicine of Sudan as anthelmintic and as a remedy against intestinal colics.The literature reported the isolation and structure elucidation of the bioactive agents as being sequi terpenes. The flavonoids of the Sudanese species were not investigated before. The present work consisted of phyto chemical study of the leaves of Polygonum galbrum wild. Before experimentation, a through authentication of the plant was done to correct previously reported errors. In the first stages a phyto chemical screening was made which confirmed the presence of flavonoid compounds in higher amounts than the other classes of natural products present in the plant. Different chromatographic techniques of isolation were assayed but the fractionation of flavonoids was successfully done with preparative thin layer chromatographic techniques. Yellow crystals, namely (two compounds) were obtained in pure form and identified as being flavonoids. Spectral studies were performed on Infra-Red and Ultra- Violet spectrophotometers. The computerized Ultra- Violet spectrophotometer allowed us to obtain complete data about the studied compounds. Structure elucidation was attempted and the structure of the isolated flavonoids were suggested as being Isorhamnetin and Diosmetin. (Author)

Effects of UV light and chromium ions on wood flavonoids

International Nuclear Information System (INIS)

Molnárné Hamvas, L.; Németh, K.; Stipta, J.

2003-01-01

The individual and simultaneous effect of UV light and chromium ions was investigated by spectrophotometric methods on inert surfaces impregnated with quercetin or robinetin. The UV-VIS spectra of the silica gel plates impregnated with these flavonoids were modified characteristically after irradiating ultraviolet light. Even a half an hour of irradiation has caused irreversible changes in the molecule structure. A certain chemical - presumably complexation - was concluded from the change of spectral bands assigned to flavonoids when impregnated with chromic ions. Hexavalent chromium caused more complex changes in the absorption spectra. The differences in the spectra could indicate either the oxidation and decomposition of flavonoids, or some kind of coordination process and the reduction of hexavalent chromium. The simultaneous application of UV light and chromium ions caused more pronounced effects. The complexation process between chromium(III) and flavonoid was completed

[Seasonal changes and response to stress of total flavonoids content of Farfugium japonicum].

Science.gov (United States)

Cui, Dalian; Ma, Yuxin

2013-05-01

To investigate the seasonal variation of total flavonoid content of Farfugium japonicum and its response to stress. The total flavonoids of Farfugium japonicum were determined by spectrophotometry in different seasons and under various stressful factors. The total flavonoid content in Farfugium japonicum leaves was the highest, followed by the petiole, and rhizomes (Pseasons (Pwater stress, the total flavonoid content in Farfugium japonicum leaves gradually increased, that in petiole first increased and then decreased,while that in rhizomes decreased (Pstress, the total flavonoid content in leaves, petioles and rhizomes of Farfugium japonicum showed a decreasing trend (Pseasons and that in different parts of the plant has different responses to ecological stressful factors.

The influence of light quality on the accumulation of flavonoids in tobacco (Nicotiana tabacum L.) leaves.

Science.gov (United States)

Fu, Bo; Ji, Xiaoming; Zhao, Mingqin; He, Fan; Wang, Xiaoli; Wang, Yiding; Liu, Pengfei; Niu, Lu

2016-09-01

Flavonoids are important secondary metabolites in plants regulated by the environment. To analyze the effect of light quality on the accumulation of flavonoids, we performed a rapid analysis of flavonoids in extracts of tobacco leaves using UHPLC-QTOF. A total of 12 flavonoids were detected and identified in tobacco leaves, which were classified into flavonoid methyl derivatives and flavonoid glycoside derivatives according to the groups linked to the flavonoid core. Correlation analysis was further conducted to investigate the effect of different wavelengths of light on their accumulation. The content of flavonoid methyl derivatives was positively correlated with the proportions of far-red light (FR; 716-810nm) and near-infrared light (NIR; 810-2200nm) in the sunlight spectrum and negatively correlated with the proportion of ultraviolet (UV-A; 350-400nm) and the red/far-red ratio (R/FR). By contrast, the content of flavonoid glycoside derivatives was positively correlated with the proportion of UV-A and the R/FR, and negatively correlated with FR and NIR. The results indicated that light quality with higher proportions of FR and NIR increases the activity of flavonoid methyltransferases but suppresses the activity of flavonoid glycoside transferases. While a high proportion of UV-A and a high R/FR can increase flavonoid glycoside transferase activity but suppress flavonoid methyltransferase activity. Copyright © 2016 Elsevier B.V. All rights reserved.

Metabolomics analysis reveals the metabolic and functional roles of flavonoids in light-sensitive tea leaves.

Science.gov (United States)

Zhang, Qunfeng; Liu, Meiya; Ruan, Jianyun

2017-03-20

As the predominant secondary metabolic pathway in tea plants, flavonoid biosynthesis increases with increasing temperature and illumination. However, the concentration of most flavonoids decreases greatly in light-sensitive tea leaves when they are exposed to light, which further improves tea quality. To reveal the metabolism and potential functions of flavonoids in tea leaves, a natural light-sensitive tea mutant (Huangjinya) cultivated under different light conditions was subjected to metabolomics analysis. The results showed that chlorotic tea leaves accumulated large amounts of flavonoids with ortho-dihydroxylated B-rings (e.g., catechin gallate, quercetin and its glycosides etc.), whereas total flavonoids (e.g., myricetrin glycoside, epigallocatechin gallate etc.) were considerably reduced, suggesting that the flavonoid components generated from different metabolic branches played different roles in tea leaves. Furthermore, the intracellular localization of flavonoids and the expression pattern of genes involved in secondary metabolic pathways indicate a potential photoprotective function of dihydroxylated flavonoids in light-sensitive tea leaves. Our results suggest that reactive oxygen species (ROS) scavenging and the antioxidation effects of flavonoids help chlorotic tea plants survive under high light stress, providing new evidence to clarify the functional roles of flavonoids, which accumulate to high levels in tea plants. Moreover, flavonoids with ortho-dihydroxylated B-rings played a greater role in photo-protection to improve the acclimatization of tea plants.

Quantitative modeling of flavonoid glycosides isolated from Paliurus spina-christi Mill.

OpenAIRE

Medić-Šarić, Marica; Maleš, Željan; Šarić, Slavko; Brantner, Adelheid

1996-01-01

Several QSPR models for predicting the properties of flavonoid glycosides isolated from Paliurus spina-christi Mill, and of some related flavonoids were described and evaluated. Log P values for all of them were calculated according to the method of Rekker. All investigated flavonoids showed expressive hydrophobicity. Significant correlation between the partition coefficient, log P, and van der Waals volume, Vw (calculated according to the method described by Moriguchi et al.) was obtained. T...

[Study on Flavonoids in Buddleja lindleyana Fruits].

Science.gov (United States)

Yu, Hao; Ren, Ya-shuo; Wu, De-ling; Xu, Feng-qing; Zhang, Wei

2015-04-01

To study the flavonoids in the fruits of Buddleja lindleyana. The compounds were separated by repeated silica gel, RP-18 and Sephadex LH-20. Their structures were elucidated on the basis of chemical evidence and spectral data. Five flavonoids were isolated and identified as luteolin (1), tricin (2), acacetin (3), acacetin-7-O-β-D-glucopyranoside (4) and linarin(5). Compounds 3,4 and 5 are isolated from fruits of Buddleja lindleyana for the first time. Compound 2 is isolated from fruits of Buddleja lindleyana for the first time.

Quantitation of flavonoid constituents in citrus fruits.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

1999-09-01

Twenty-four flavonoids have been determined in 66 Citrus species and near-citrus relatives, grown in the same field and year, by means of reversed phase high-performance liquid chromatography analysis. Statistical methods have been applied to find relations among the species. The F ratios of 21 flavonoids obtained by applying ANOVA analysis are significant, indicating that a classification of the species using these variables is reasonable to pursue. Principal component analysis revealed that the distributions of Citrus species belonging to different classes were largely in accordance with Tanaka's classification system.

Study on the high flavonoids mutants of tartarian buckwheat by radiation induced mutation

International Nuclear Information System (INIS)

Li Guozhu; Shen Huifang

2012-01-01

Three different varieties of tartarian buckwheat seeds (Chuanqiao 1#, Yu-621 and KP9920) were irradiated with various doses (100∼500 Gy) of 60 Co-γ ray and sowed. Ten, eight and six high flavonoid tartary buckwheat mutants were selected from three parent materials respectively. The flavonoid content of three parent materials were 8.33%, 10.18% and 9.80%. The range of flavonoid content of high flavonoids mutants for three parent materials 11.37%∼14.91%, 10.67%∼12.46% and 11.32%∼12.95% respectively. Cluster analysis was also carried out based on the agronomic traits and flavonoid content in the 27 tartary buckwheat materials (24 mutants and 3 parent material) The 27 materials were classified into four clusters by cluster analysis based on the agronomic traits and were classified into 5 groups based on flavonoid content. (authors)

Phyto chemical study of the flavonoids of khaya senegalensis

International Nuclear Information System (INIS)

Shakir, S. H.

2005-03-01

Phyto chemical screening of the leaves of Khaya senegalensis revealed the presence of flavonoids. Crushed air-dried leaves of Khaya senegalensis were extracted at ambient temperature with ethanol. The crude product obtained after removal of the solvent was subjected to chromatographic fractionation. Using silica gel and the solvent system: butanol: acetic acid: water (3:1:6 ; V:V:V) a pure flavonoid was isolated. The colour reactions and the UV spectra of the isolated flavonoid clearly indicated that it is a flavone. The hydroxylation pattern of the isolated flavone was studies using shift reagents. The structural features were further elucidated via IR, NMR and Mass spectrophotometry. The following tentative structure was proposed.(Author)

Eriosema (Fabaceae) Species Represent a Rich Source of Flavonoids with Interesting Pharmacological Activities.

Science.gov (United States)

Awouafack, Maurice Ducret; Tane, Pierre; Spiteller, Michael; Eloff, Jacobus Nicolaas

2015-07-01

Many flavonoids have so far been isolated as main secondary metabolites in plant species of the genus Eriosema (Fabaceae), which contains approximately 160 species. A total of 52 flavonoids including isoflavones, dihydroflavonols, flavonols, flavanones, dihydrochalcones, isoflavanone and their pyrano or glucoside derivatives were isolated and characterized from the five species of this genus investigated to date. Total synthesis and semi-synthesis (acetylation, methylation, hydrogenation, and cyclization) of some isolated flavonoids were reported. Due to several significant pharmacological properties (antimicrobial, cytotoxicity, anti-mycobacterial, antioxidant, antiviral, erectile-dysfunction, vasodilatory and hypoglycemic) of the isolated flavonoids and derivatives, more scientists should be interested in investigating Eriosema species. The present review is the first to document all flavonoids that have been reported from the genus Eriosema to date together with their synthetic and semi-synthetic derivatives, and their pharmacological properties. Dihydrochalcones, which are precursors of other classes of flavonoids, are very rare in natural sources and their isolation from Eriosema species may explain the large number of flavonoids found in this genus. It appears that isoflavone could be a marker for species in this genus. The 83 flavonoids (1-83) documented include 52 isolates, 31 semi-synthetic and 3 totally synthetic derivatives. Data were obtained from Google scholar, Pubmed, Scifinder, Sciencedirect, and Scopus. With 52 different flavonoids isolated from only 5 of the approximately 160 species it shows the remarkable chemical diversity of this genus. This compilation of the biological activities and chemical composition may renew the interest of pharmacologists and phytochemists in this genus.

Deterrent activity of hops flavonoids and their derivatives against stored product pests.

Science.gov (United States)

Jackowski, J; Popłoński, J; Twardowska, K; Magiera-Dulewicz, J; Hurej, M; Huszcza, E

2017-10-01

Five flavonoids from hops, two of their derivatives, along with naringenin used as a model compound, were tested for their antifeedant activity against three coleopteran stored product pests: Sitophilus granarius L., Tribolium confusum Duv. and Trogoderma granarium Everts. The introduction, into the tested flavonoid molecules, of additional structural fragments such as prenyl or dimethylpyran moiety, is proposed to significantly alter the deterrent activity of the compounds. The prenyl moiety in flavonoids increased the deterrent activity of these compounds in all three of the grain feeding species used in the tests. It is also concluded that the introduction of dimethylpyran moiety to the flavonoid structure increases its deterrent activity in S. granarius and T. confusum, but in one of the test insects, T. granarium, an increased feeding was observed in response to the introduction of dimethylpyran moiety to the flavonoid structure.

The score statistic of the LD-lod analysis: detecting linkage adaptive to linkage disequilibrium.

Science.gov (United States)

Huang, J; Jiang, Y

2001-01-01

We study the properties of a modified lod score method for testing linkage that incorporates linkage disequilibrium (LD-lod). By examination of its score statistic, we show that the LD-lod score method adaptively combines two sources of information: (a) the IBD sharing score which is informative for linkage regardless of the existence of LD and (b) the contrast between allele-specific IBD sharing scores which is informative for linkage only in the presence of LD. We also consider the connection between the LD-lod score method and the transmission-disequilibrium test (TDT) for triad data and the mean test for affected sib pair (ASP) data. We show that, for triad data, the recessive LD-lod test is asymptotically equivalent to the TDT; and for ASP data, it is an adaptive combination of the TDT and the ASP mean test. We demonstrate that the LD-lod score method has relatively good statistical efficiency in comparison with the ASP mean test and the TDT for a broad range of LD and the genetic models considered in this report. Therefore, the LD-lod score method is an interesting approach for detecting linkage when the extent of LD is unknown, such as in a genome-wide screen with a dense set of genetic markers. Copyright 2001 S. Karger AG, Basel

Cytotoxic flavonoids from Erythrina caffra Thunb | Y. Desta | Bulletin ...

African Journals Online (AJOL)

Erythrina caffra is an important medicinal plant native to South Africa. Its stem bark was investigated for the flavonoid constituents and biological activity. Some isolated flavonoids, 3, 5, 6, 8, 9, 10, 11, 12, 13, 15 and 16 were found to be active against the human cervix carcinoma KB-3-1 cells with IC50 values in the ...

Electrochemical study of the increased antioxidant capacity of flavonoids through complexation with iron(II) ions

International Nuclear Information System (INIS)

Porfírio, Demóstenes Amorim; Ferreira, Rafael de Queiroz; Malagutti, Andréa Renata; Valle, Eliana Maíra Agostini

2014-01-01

Highlights: • Metal-Flavonoid complexes exhibit greater antioxidant capacity than the free flavonoid;. • Voltammetric profile is an additional information for determining antioxidant capacity;. • Pyrogallol group is a stronger complex-forming group than the catechol;. • Morin, quercetin and fisetin increased their antioxidant capacity in 15%, 32% and 28%, respectively. - Abstract: Flavonoids are polyphenolic compounds that act as natural antioxidants in the human body through various mechanisms, with an emphasis on suppressing reactive oxygen species (ROS) formation by inhibiting enzymes, the direct capture of ROS, and the regulation/protection of antioxidant defenses. Additionally, flavonoids can coordinate with transition metals to catalyze electron transport and promote free radical capture. Recently, metal ion chelation mechanisms have generated considerable interest, as experimental data show that flavonoids in metal complexes exhibit greater antioxidant activity than free flavonoids. However, few studies have correlated the complexing properties of flavonoids with their antioxidant capacity. Thus, the aim of this study was to use the CRAC (Ceric Reducing Antioxidant Capacity) electrochemical assay to measure the antioxidant capacity of five free flavonoids and Fe 2+ -flavonoid complexes. In addition, the interactions between the flavonoids and Fe 2+ were analyzed based on the oxidation peaks formed in their cyclic voltammograms

Effects of Acute Blueberry Flavonoids on Mood in Children and Young Adults

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Sundus Khalid

2017-02-01

Full Text Available Epidemiological evidence suggests that consumption of flavonoids (usually via fruits and vegetables is associated with decreased risk of developing depression. One plausible explanation for this association is the well-documented beneficial effects of flavonoids on executive function (EF. Impaired EF is linked to cognitive processes (e.g., rumination that maintain depression and low mood; therefore, improved EF may reduce depressionogenic cognitive processes and improve mood. Study 1: 21 young adults (18–21 years old consumed a flavonoid-rich blueberry drink and a matched placebo in a counterbalanced cross-over design. Study 2: 50 children (7–10 years old were randomly assigned to a flavonoid-rich blueberry drink or a matched placebo. In both studies, participants and researchers were blind to the experimental condition, and mood was assessed using the Positive and Negative Affect Schedule before and 2 h after consumption of the drinks. In both studies, the blueberry intervention increased positive affect (significant drink by session interaction but had no effect on negative affect. This observed effect of flavonoids on positive affect in two independent samples is of potential practical value in improving public health. If the effect of flavonoids on positive affect is replicated, further investigation will be needed to identify the mechanisms that link flavonoid interventions with improved positive mood.

Pathway Analysis Revealed Potential Diverse Health Impacts of Flavonoids that Bind Estrogen Receptors

Science.gov (United States)

Ye, Hao; Ng, Hui Wen; Sakkiah, Sugunadevi; Ge, Weigong; Perkins, Roger; Tong, Weida; Hong, Huixiao

2016-01-01

Flavonoids are frequently used as dietary supplements in the absence of research evidence regarding health benefits or toxicity. Furthermore, ingested doses could far exceed those received from diet in the course of normal living. Some flavonoids exhibit binding to estrogen receptors (ERs) with consequential vigilance by regulatory authorities at the U.S. EPA and FDA. Regulatory authorities must consider both beneficial claims and potential adverse effects, warranting the increases in research that has spanned almost two decades. Here, we report pathway enrichment of 14 targets from the Comparative Toxicogenomics Database (CTD) and the Herbal Ingredients’ Targets (HIT) database for 22 flavonoids that bind ERs. The selected flavonoids are confirmed ER binders from our earlier studies, and were here found in mainly involved in three types of biological processes, ER regulation, estrogen metabolism and synthesis, and apoptosis. Besides cancers, we conjecture that the flavonoids may affect several diseases via apoptosis pathways. Diseases such as amyotrophic lateral sclerosis, viral myocarditis and non-alcoholic fatty liver disease could be implicated. More generally, apoptosis processes may be importantly evolved biological functions of flavonoids that bind ERs and high dose ingestion of those flavonoids could adversely disrupt the cellular apoptosis process. PMID:27023590

Pathway Analysis Revealed Potential Diverse Health Impacts of Flavonoids that Bind Estrogen Receptors

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Hao Ye

2016-03-01

Full Text Available Flavonoids are frequently used as dietary supplements in the absence of research evidence regarding health benefits or toxicity. Furthermore, ingested doses could far exceed those received from diet in the course of normal living. Some flavonoids exhibit binding to estrogen receptors (ERs with consequential vigilance by regulatory authorities at the U.S. EPA and FDA. Regulatory authorities must consider both beneficial claims and potential adverse effects, warranting the increases in research that has spanned almost two decades. Here, we report pathway enrichment of 14 targets from the Comparative Toxicogenomics Database (CTD and the Herbal Ingredients’ Targets (HIT database for 22 flavonoids that bind ERs. The selected flavonoids are confirmed ER binders from our earlier studies, and were here found in mainly involved in three types of biological processes, ER regulation, estrogen metabolism and synthesis, and apoptosis. Besides cancers, we conjecture that the flavonoids may affect several diseases via apoptosis pathways. Diseases such as amyotrophic lateral sclerosis, viral myocarditis and non-alcoholic fatty liver disease could be implicated. More generally, apoptosis processes may be importantly evolved biological functions of flavonoids that bind ERs and high dose ingestion of those flavonoids could adversely disrupt the cellular apoptosis process.

De novo production of the flavonoid naringenin in engineered Saccharomyces cerevisiae

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Koopman Frank

2012-12-01

Full Text Available Abstract Background Flavonoids comprise a large family of secondary plant metabolic intermediates that exhibit a wide variety of antioxidant and human health-related properties. Plant production of flavonoids is limited by the low productivity and the complexity of the recovered flavonoids. Thus to overcome these limitations, metabolic engineering of specific pathway in microbial systems have been envisaged to produce high quantity of a single molecules. Result Saccharomyces cerevisiae was engineered to produce the key intermediate flavonoid, naringenin, solely from glucose. For this, specific naringenin biosynthesis genes from Arabidopsis thaliana were selected by comparative expression profiling and introduced in S. cerevisiae. The sole expression of these A. thaliana genes yielded low extracellular naringenin concentrations ( Conclusion The results reported in this study demonstrate that S. cerevisiae is capable of de novo production of naringenin by coexpressing the naringenin production genes from A. thaliana and optimization of the flux towards the naringenin pathway. The engineered yeast naringenin production host provides a metabolic chassis for production of a wide range of flavonoids and exploration of their biological functions.

Physiological Studies on Pea Tendrils. IV. Flavonoids and Contact Coiling

Science.gov (United States)

Jaffe, M. J.; Galston, A. W.

1967-01-01

Pea tendrils contain high concentrations of flavonoids, mainly quercetin-triglucosyl-p-coumarate (QGC). QGC is most abundant near the highly responsive apex of the tendril, and least abundant at the base. After mechanical stimulation, and during coiling of the tendril, the QGC titer drops to about 30% of its original value. The kinetics of flavonoid disappearance are significantly correlated with the kinetics of coiling. Aqueous extracts of unstimulated pea tendrils or 10 μm QGC inhibit contact coiling of excised tendrils. Extracts of coiled tendrils do not. The evidence indicates a possible regulatory role for flavonoids in contact coiling. PMID:16656581

Probabilistic linkage to enhance deterministic algorithms and reduce data linkage errors in hospital administrative data.

Science.gov (United States)

Hagger-Johnson, Gareth; Harron, Katie; Goldstein, Harvey; Aldridge, Robert; Gilbert, Ruth

2017-06-30

 BACKGROUND: The pseudonymisation algorithm used to link together episodes of care belonging to the same patients in England (HESID) has never undergone any formal evaluation, to determine the extent of data linkage error. To quantify improvements in linkage accuracy from adding probabilistic linkage to existing deterministic HESID algorithms. Inpatient admissions to NHS hospitals in England (Hospital Episode Statistics, HES) over 17 years (1998 to 2015) for a sample of patients (born 13/28th of months in 1992/1998/2005/2012). We compared the existing deterministic algorithm with one that included an additional probabilistic step, in relation to a reference standard created using enhanced probabilistic matching with additional clinical and demographic information. Missed and false matches were quantified and the impact on estimates of hospital readmission within one year were determined. HESID produced a high missed match rate, improving over time (8.6% in 1998 to 0.4% in 2015). Missed matches were more common for ethnic minorities, those living in areas of high socio-economic deprivation, foreign patients and those with 'no fixed abode'. Estimates of the readmission rate were biased for several patient groups owing to missed matches, which was reduced for nearly all groups. CONCLUSION: Probabilistic linkage of HES reduced missed matches and bias in estimated readmission rates, with clear implications for commissioning, service evaluation and performance monitoring of hospitals. The existing algorithm should be modified to address data linkage error, and a retrospective update of the existing data would address existing linkage errors and their implications.

The Creation and Physiological Relevance of Divergent Hydroxylation Patterns in the Flavonoid Pathway

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Heidi Halbwirth

2010-02-01

Full Text Available Flavonoids and biochemically-related chalcones are important secondary metabolites, which are ubiquitously present in plants and therefore also in human food. They fulfill a broad range of physiological functions in planta and there are numerous reports about their physiological relevance for humans. Flavonoids have in common a basic C6-C3-C6 skeleton structure consisting of two aromatic rings (A and B and a heterocyclic ring (C containing one oxygen atom, whereas chalcones, as the intermediates in the formation of flavonoids, have not yet established the heterocyclic C-ring. Flavonoids are grouped into eight different classes, according to the oxidative status of the C-ring. The large number of divergent chalcones and flavonoid structures is from the extensive modification of the basic molecules. The hydroxylation pattern influences physiological properties such as light absorption and antioxidative activity, which is the base for many beneficial health effects of flavonoids. In some cases antiinfective properties are also effected.

A Formalization of Linkage Analysis

DEFF Research Database (Denmark)

Ingolfsdottir, Anna; Christensen, A.I.; Hansen, Jens A.

In this report a formalization of genetic linkage analysis is introduced. Linkage analysis is a computationally hard biomathematical method, which purpose is to locate genes on the human genome. It is rooted in the new area of bioinformatics and no formalization of the method has previously been ...

The anti-cancer charm of flavonoids: a cup-of-tea will do!

Science.gov (United States)

Amin, Amr; Buratovich, Michael

2007-06-01

Hormone-dependent cancers of the breast, prostate and colon have, in the past decade, become the leading causes of morbidity and mortality. Billions of dollars have been, and still are being spent to study cancers like these, and, in the past three decades, thanks to work by thousands of dedicated scientists, tremendous advancements in the understanding and treatment of cancer have been made. Nevertheless, as there is no sure-fire cure for a variety of cancers to date, natural protection against cancer has been receiving a great deal of attention lately not only from cancer patients but, surprisingly, from physicians as well. Phytoestrogens, plant-derived secondary metabolites, are diphenolic substances with structural similarity to naturally-occurring human steroid hormones. Phytoestrogens are normally divided into three main classes: flavonoids, coumestans and lignans. Flavonoids are found in almost all plant families in the leaves, stems, roots, flowers and seeds of plants and are among the most popular anti-cancer candidates. Flavonoidic derivatives have a wide range of biological actions such as antibacterial, antiviral, anti-inflammatory, anticancer, and antiallergic activities. Some of these benefits are explained by the potent antioxidant effects of flavonoids, which include metal chelation and free-radical scavenging activities. Patent applications regarding flavonoids range from protocols for extraction and purification from natural resources and the establishment of various biological activities for these extracts to novel methods for the production and isolation of flavonoids with known biological activities. This review will bring the reader up to date on the current knowledge and research available in the field of flavonoids and hormone-dependent cancers, and many of the submitted patents that exploit flavonoids.

Flavonoid intake and cardiovascular disease mortality: a prospective study in postmenopausal women.

Science.gov (United States)

Mink, Pamela J; Scrafford, Carolyn G; Barraj, Leila M; Harnack, Lisa; Hong, Ching-Ping; Nettleton, Jennifer A; Jacobs, David R

2007-03-01

Dietary flavonoids may have beneficial cardiovascular effects in human populations, but epidemiologic study results have not been conclusive. We used flavonoid food composition data from 3 recently available US Department of Agriculture databases to improve estimates of dietary flavonoid intake and to evaluate the association between flavonoid intake and cardiovascular disease (CVD) mortality. Study participants were 34 489 postmenopausal women in the Iowa Women's Health Study who were free of CVD and had complete food-frequency questionnaire information at baseline. Intakes of total flavonoids and 7 subclasses were categorized into quintiles, and food sources were grouped into frequency categories. Proportional hazards rate ratios (RR) were computed for CVD, coronary heart disease (CHD), stroke, and total mortality after 16 y of follow-up. After multivariate adjustment, significant inverse associations were observed between anthocyanidins and CHD, CVD, and total mortality [RR (95% CI) for any versus no intake: 0.88 (0.78, 0.99), 0.91 (0.83, 0.99), and 0.90 (0.86, 0.95)]; between flavanones and CHD [RR for highest quintile versus lowest: 0.78 (0.65, 0.94)]; and between flavones and total mortality [RR for highest quintile versus lowest: 0.88 (0.82, 0.96)]. No association was found between flavonoid intake and stroke mortality. Individual flavonoid-rich foods associated with significant mortality reduction included bran (added to foods; associated with stroke and CVD); apples or pears or both and red wine (associated with CHD and CVD); grapefruit (associated with CHD); strawberries (associated with CVD); and chocolate (associated with CVD). Dietary intakes of flavanones, anthocyanidins, and certain foods rich in flavonoids were associated with reduced risk of death due to CHD, CVD, and all causes.

Light quality affects flavonoid production and related gene expression in Cyclocarya paliurus.

Science.gov (United States)

Liu, Yang; Fang, Shengzuo; Yang, Wanxia; Shang, Xulan; Fu, Xiangxiang

2018-02-01

Understanding the responses of plant growth and secondary metabolites to differential light conditions is very important to optimize cultivation conditions of medicinal woody plants. As a highly valued and multiple function tree species, Cyclocarya paliurus is planted and managed for timber production and medical use. In this study, LED-based light including white light (WL), blue light (BL), red light (RL), and green light (GL) were used to affect leaf biomass production, flavonoid accumulation and related gene expression of one-year C. paliurus seedlings in controlled environments. After the treatments of 60 days, the highest leaf biomass appeared in the treatment of WL, while the lowest leaf biomass was found under GL. Compared to WL, the total flavonoid contents of C. paliurus leaves were significantly higher in BL, RL, and GL, but the highest values of selected flavonoids (kaempferol, isoquercitrin and quercetin) were observed under BL. Furthermore, the greatest yields of total and selected flavonoids in C. paliurus leaves per seedling were also achieved under BL, indicating that blue light was effective for inducing the production of flavonoids in C. paliurus leaves. Pearson's correlation analysis showed that there were significantly positive correlations between leaf flavonoid content and relative gene expression of key enzymes (phenylalanine ammonia lyase, PAL; 4-coumaroyl CoA-ligase, 4CL; and chalcone synthase, CHS) in the upstream, which converting phenylalanine into the flavonoid skeleton of tetrahydroxy chalcone. It is concluded that manipulating light quality may be potential mean to achieve the highest yields of flavonoids in C. paliurus cultivation, however this needs to be further verified by more field trials. Copyright © 2018 Elsevier B.V. All rights reserved.

Flavonoids Modulate the Proliferation of Neospora caninum in Glial Cell Primary Cultures

Science.gov (United States)

Barbosa de Matos, Rosan; Braga-de-Souza, Suzana; Pena Seara Pitanga, Bruno; Amaral da Silva, Victor Diógenes; Viana de Jesus, Erica Etelvina; Morales Pinheiro, Alexandre; Dias Costa, Maria de Fátima; dos Santos El-Bacha, Ramon; de Oliveira Ribeiro, Cátia Suse

2014-01-01

Neospora caninum (Apicomplexa; Sarcocystidae) is a protozoan that causes abortion in cattle, horses, sheep, and dogs as well as neurological and dermatological diseases in dogs. In the central nervous system of dogs infected with N. caninum, cysts were detected that exhibited gliosis and meningitis. Flavonoids are polyphenolic compounds that exhibit antibacterial, antiparasitic, antifungal, and antiviral properties. In this study, we investigated the effects of flavonoids in a well-established in vitro model of N. caninum infection in glial cell cultures. Glial cells were treated individually with 10 different flavonoids, and a subset of cultures was also infected with the NC-1 strain of N. caninum. All of the flavonoids tested induced an increase in the metabolism of glial cells and many of them increased nitrite levels in cultures infected with NC-1 compared to controls and uninfected cultures. Among the flavonoids tested, 3',4'-dihydroxyflavone, 3',4',5,7-tetrahydroxyflavone (luteolin), and 3,3',4',5,6-pentahydroxyflavone (quercetin), also inhibited parasitophorous vacuole formation. Taken together, our findings show that flavonoids modulate glial cell responses, increase NO secretion, and interfere with N. caninum infection and proliferation. PMID:25548412

Chemosystematic significance of flavonoids isolated from Diplotaxis acris (Brassicaceae) and related taxa.

Science.gov (United States)

Hussein, Sameh R; Marzouk, Mona M; Kassem, Mona E S; Abdel Latif, Rasha R; Mohammed, Reda S

2017-02-01

The chemosystematic relationship of four Diplotaxis species; Diplotaxis acris, Diplotaxis erucoides, Diplotaxis harra and Diplotaxis muralis were surveyed from the flavonoids point of view. These species were found to produce 33 flavonoids (7 flavones and 26 flavonols), including 11 compounds were isolated in the present study from D. acris. Among them, seven flavonoids were identified for the first time; luteolin (4), kaempferol (8), kaempferol 3-O-β-glucopyranoside-7-O-α-rhamnopyranoside (13), quercetin 3-O-β-glucopyranoside (16), quercetin 7-O-β-glucopyranoside (20), isorhamnetin (22) and isorhamnetin 3-O-β-glucopyranoside-7-O-α-rhamnopyranoside (32). Their structures were recognized on the basis of chemical and spectroscopic techniques (1D & 2D NMR, UV, EI & ESI/MS). The isolated flavonoids may provide useful taxonomic characters at the infraspecific levels of classification where the flavonoid profile of D. acris and D. harra is similar and different from the other species.

Flavonoid engineering of flax potentiate its biotechnological application

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Prescha Anna

2011-01-01

Full Text Available Abstract Background Flavonoids are a group of secondary plant metabolites important for plant growth and development. They show also a protective effect against colon and breast cancer, diabetes, hypercholesterolemic atherosclerosis, lupus nephritis, and immune and inflammatory reactions. Thus, overproduction of these compounds in flax by genetic engineering method might potentiate biotechnological application of these plant products. Results Flax plants of third generation overexpressing key genes of flavonoid pathway cultivated in field were used as plant material throughout this study. The biochemical properties of seed, oil and seedcake extracts and fibre from natural and transgenic flax plants were compared. The data obtained suggests that the introduced genes were stably inherited and expressed through plant generations. Overproduction of flavonoid compounds resulted in increase of fatty acids accumulation in oil from transgenic seeds due to protection from oxidation offered during synthesis and seed maturation. The biochemical analysis of seedcake extracts from seeds of transgenic flax revealed significant increase in flavonoids (kaempferol, phenolic acids (coumaric, ferulic, synapic acids and lignan content. Fibres, another product of flax plant showed increase in the level of catechine and acetylvanillone and decrease in phenolic acids upon flax modification. Biochemical analysis results were confirmed using IR spectroscopy. The integral intensities of IR bands have been used for identification of the component of phenylpropanoid pathway in oil, seedcake extract and fibre from control and transgenic flax. It was shown that levels of flavonoids, phenolic acids and lignans in oil and seedcake extract was higher in transgenic flax products compared to control. An FT-IR study of fibres confirmed the biochemical data and revealed that the arrangement of the cellulose polymer in the transgenic fibres differs from the control; in particular a

Effect of room temperature ionic liquid structure on the enzymatic acylation of flavonoids

DEFF Research Database (Denmark)

Lue, Bena-Marie; Guo, Zheng; Xu, Xuebing

2010-01-01

Enzymatic acylation reactions of flavonoids (rutin, esculin) with long chain fatty acids (palmitic, oleic acids) were carried out in 14 different ionic liquid media containing a range of cation and anion structures. Classification of RTILs according to flavonoid solubility (using COSMO...... must be struck that maximized flavonoid solubility with minimum negative impact on lipase activity. The process also benefitted from an increased reaction temperature which may have helped to reduced mass transfer limitations. Keywords: Room temperature ionic liquids (RTILs); Biosynthesis; Acylation......; Flavonoids; Lipase; Long chain fatty acids...

Optimization of the extraction of flavonoids from grape leaves by response surface methodology

International Nuclear Information System (INIS)

Brad, K.; Liu, W.

2013-01-01

The extraction of flavonoids from grape leaves was optimized to maximize flavonoids yield in this study. A central composite design of response surface methodology involving extracting time, power, liquid-solid ratio, and concentration was used, and second-order model for Y was employed to generate the response surfaces. The optimum condition for flavonoids yield was determined as follows: extracting time 24.95 min, power 72.05, ethanol concentration 63.35%, liquid-solid ratio 10.04. Under the optimum condition, the flavonoids yield was 76.84 %. (author)

Modification of abomasum contractility by flavonoids present in ruminants diet: in vitro study.

Science.gov (United States)

Mendel, M; Chłopecka, M; Dziekan, N; Karlik, W

2016-09-01

Flavonoid supplementation is likely to be beneficial in improving rumen fermentation and in reducing the incidence of rumen acidosis and bloat. Flavonoids are also said to increase the metabolic performance during the peripartum period. Ruminants are constantly exposed to flavonoids present in feed. However, it is not clear if these phytochemicals can affect the activity of the gut smooth muscle. Therefore, the aim of the study was to verify the effect of three flavonoids on bovine isolated abomasum smooth muscle. The study was carried out on bovine isolated circular and longitudinal abomasal smooth muscle specimens. All experiments were conducted under isometric conditions. The effect of apigenin, luteolin and quercetin (0.001 to 100 µM) was evaluated on acetylcholine-precontracted preparations. The effect of multiple, but not cumulative, treatment and single treatment with each flavonoid on abomasum strips was compared. Apigenin (0.1 to 100 µM) dose-dependently showed myorelaxation effects. Luteolin and quercetin applied in low doses increased the force of the ACh-evoked reaction. However, if used in high doses in experiments testing a wide range of concentrations, their contractile effect either declined (luteolin) or was replaced by an antispasmodic effect (quercetin). Surprisingly, the reaction induced by flavonoids after repeated exposure to the same phytochemical was not reproducible in experiments testing only single exposure of abomasum strips to the same flavonoid used in a high concentration. Taking into account the physicochemical properties of flavonoids, this data suggests the ability of flavonoids to interfere with cell membranes and, subsequently, to modify their responsiveness. Assuming ruminant supplementation with luteolin or quercetin or their presence in daily pasture, a reduction of the likelihood of abomasum dysmotility should be expected.

A chemical profiling strategy for semi-quantitative analysis of flavonoids in Ginkgo extracts.

Science.gov (United States)

Yang, Jing; Wang, An-Qi; Li, Xue-Jing; Fan, Xue; Yin, Shan-Shan; Lan, Ke

2016-05-10

Flavonoids analysis in herbal products is challenged by their vast chemical diversity. This work aimed to develop a chemical profiling strategy for the semi-quantification of flavonoids using extracts of Ginkgo biloba L. (EGB) as an example. The strategy was based on the principle that flavonoids in EGB have an almost equivalent molecular absorption coefficient at a fixed wavelength. As a result, the molecular-contents of flavonoids were able to be semi-quantitatively determined by the molecular-concentration calibration curves of common standards and recalculated as the mass-contents with the characterized molecular weight (MW). Twenty batches of EGB were subjected to HPLC-UV/DAD/MS fingerprinting analysis to test the feasibility and reliability of this strategy. The flavonoid peaks were distinguished from the other peaks with principle component analysis and Pearson correlation analysis of the normalized UV spectrometric dataset. Each flavonoid peak was subsequently tentatively identified by the MS data to ascertain their MW. It was highlighted that the flavonoids absorption at Band-II (240-280 nm) was more suitable for the semi-quantification purpose because of the less variation compared to that at Band-I (300-380 nm). The semi-quantification was therefore conducted at 254 nm. Beyond the qualitative comparison results acquired by common chemical profiling techniques, the semi-quantitative approach presented the detailed compositional information of flavonoids in EGB and demonstrated how the adulteration of one batch was achieved. The developed strategy was believed to be useful for the advanced analysis of herbal extracts with a high flavonoid content without laborious identification and isolation of individual components. Copyright © 2016 Elsevier B.V. All rights reserved.

Flavonoids from Lonchocarpus muehlbergianus

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Magalhães Aderbal F.

2004-01-01

Full Text Available The light petroleum extract from the roots of Lonchocarpus muehlbergianus Hassl contained nine flavonoids, including six new ones. These are 2,4-cis-2,4,5,8-tetramethoxy-(2,3:6,7-furanoflavan; 2,4-cis-4-hydroxy-2,5,8-trimethoxy-(2,3:6,7-furanoflavan; 2,4-cis-2-prenyloxy-4,5,8-trimethoxy-(2,3:6,7-fu-ranoflavan; 2,4-cis-2-prenyloxy-4-hydroxy-5,8-dimethoxy-(2,3:6,7-furanoflavan; 2',5',6'-trimethoxy-9-(1,1-dimethylallyoxy-[2,3:3,4]-furanochalcone; 5,6-dimethoxy-(2,3:7,8-furanoflavone, identi-fied by analysis of their spectral data (UV, IR, ¹H and 13C NMR, 2D-NMR, NOE and MS. The natural occurrence of 2,4-dioxygenated flavan derivatives is being reported for the first time. Quantitative analysis of the petrol extract, by using reversed-phase HPLC, showed that the most abundant flavonoid in the extract is 2,4-cis-2,4,5,8- tetramethoxy-(2,3:6,7-furanoflavan.

Thermally actuated linkage arrangement

International Nuclear Information System (INIS)

Anderson, P.M.

1981-01-01

A reusable thermally actuated linkage arrangement includes a first link member having a longitudinal bore therein adapted to receive at least a portion of a second link member therein, the first and second members being sized to effect an interference fit preventing relative movement there-between at a temperature below a predetermined temperature. The link members have different coefficients of thermal expansion so that when the linkage is selectively heated by heating element to a temperature above the predetermined temperature, relative longitudinal and/or rotational movement between the first and second link members is enabled. Two embodiments of a thermally activated linkage are disclosed which find particular application in actuators for a grapple head positioning arm in a nuclear reactor fuel handling mechanism to facilitate back-up safety retraction of the grapple head independently from the primary fuel handling mechanism drive system. (author)

[HPLC fingerprint analysis of flavonoids of phyllanthi fructus from different habitats].

Science.gov (United States)

Wang, Fei; Wang, Shuai; Meng, Xian-sheng; Bao, Yong-rui; Zhu, Ying-huan

2014-11-01

To establish the HPLC fingerprint of flavonoids of Phyllanthi Fructus from different habitats. HPLC method was adopted. The flavonoids composition of Phyllanthi Fructus from 10 different habitats was determined on an Agilent C, chromatographic column with 0. 5% formic acid water (A)-acetonitrile (B) as the mobile phase in gradient elution under the wavelength of 254 nm. The HPLC fingerprints of flavonoids composition of Phyllanthi Fructus were established to evaluate the qualitiy of them. The HPLC fingerprints of flavonoids composition of Phyllanthi Fructus from 10 different habitats were established. 18 common peaks were found and the similarities of them were more than 0. 90 except the ones from Guangxi and Guangdong. The method is simple, accurate and repeatable. It can be used for research and quality control of the effective components in Phyllanthi Fructus.

Pressurised liquid extraction of flavonoids in onions. Method development and validation

DEFF Research Database (Denmark)

Søltoft, Malene; Christensen, J.H.; Nielsen, J.

2009-01-01

A rapid and reliable analytical method for quantification of flavonoids in onions was developed and validated. Five extraction methods were tested on freeze-dried onions and subsequently high performance liquid chromatography (HPLC) with UV detection was used for quantification of seven flavonoids...... extraction methods. However. PLE was the preferred extraction method because the method can be highly automated, use only small amounts of solvents, provide the cleanest extracts, and allow the extraction of light and oxygen-sensitive flavonoids to be carried out in an inert atmosphere protected from light......-step PLE method showed good selectivity, precision (RSDs = 3.1-11%) and recovery of the extractable flavonoids (98-99%). The method also appeared to be a multi-method, i.e. generally applicable to, e.g. phenolic acids in potatoes and carrots....

Lettuce flavonoids screening and phenotyping by chlorophyll fluorescence excitation ratio.

Science.gov (United States)

Zivcak, Marek; Brückova, Klaudia; Sytar, Oksana; Brestic, Marian; Olsovska, Katarina; Allakhverdiev, Suleyman I

2017-06-01

Environmentally induced variation and the genotypic differences in flavonoid and phenolic content in lettuce can be reliably detected using the appropriate parameters derived from the records of rapid non-invasive fluorescence technique. The chlorophyll fluorescence excitation ratio method was designed as a rapid and non-invasive tool to estimate the content of UV-absorbing phenolic compounds in plants. Using this technique, we have assessed the dynamics of accumulation of flavonoids related to developmental changes and environmental effects. Moreover, we have tested appropriateness of the method to identify the genotypic differences and fluctuations in total phenolics and flavonoid content in lettuce. Six green and two red genotypes of lettuce (Lactuca sativa L.) grown in pots were exposed to two different environments for 50 days: direct sunlight (UV-exposed) and greenhouse conditions (low UV). The indices based on the measurements of chlorophyll fluorescence after red, green and UV excitation indicated increase of the content of UV-absorbing compounds and anthocyanins in the epidermis of lettuce leaves. In similar, the biochemical analyses performed at the end of the experiment confirmed significantly higher total phenolic and flavonoid content in lettuce plants exposed to direct sun compared to greenhouse conditions and in red compared to green genotypes. As the correlation between the standard fluorescence indices and the biochemical records was negatively influenced by the presence of red genotypes, we proposed the use of a new parameter named Modified Flavonoid Index (MFI) taking into an account both absorbance changes due to flavonol and anthocyanin content, for which the correlation with flavonoid and phenolic content was relatively good. Thus, our results confirmed that the fluorescence excitation ratio method is useful for identifying the major differences in phenolic and flavonoid content in lettuce plants and it can be used for high-throughput pre

Assessment of total flavonoid content and antioxidant activity of Mullein (Verbascum songaricum ecotypes

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2017-11-01

Full Text Available Background and objectives: The Mullein genus is the largest genus of Scrophulariaceae family which has extensive natural habitat in southwest of Iran. Mullein contains compounds such as phenolic compounds, mucilage, saponins and anthocyanin. The aim of this study was to evaluate the total flavonoid content and antioxidant activity of mullein ecotypes in Iran. Methods: Six ecotypes of the Verbascum songaricum were evaluated. Determination of total flavonoid content was performed bythealuminium chloride colourimetric method. The antioxidant activity of the flower extracts was measured using the DPPH method. Results: The results showed that total flavonoid content and antioxidant activity were different among ecotypes.  The highest and lowest amounts of total flavonoidwas obtained  from Shermard ecotype (13.42 mg rutin /g DW and Klar ecotypes(10.10 mg rutin /g DW, respectively. The highest amounts of antioxidant activity were obtained from the Shermard ecotype (IC50 246.35 μg/mL. The correlation analysis showed that a significant relation between flavonoid, antioxidant activity and habitat elevation. Conclusion: Total flavonoid content and antioxidant activity of the samples were affected by habitat climatic.  The present data indicated that the highest antioxidant activity may be due to higher flavonoid content and the habitat elevation was effective on the flavonoid content. Due to the high amounts of flavonoid and antioxidant activity of mullein extract, it seems to be a good herbal option as an antioxidant in complementary therapies.

Recent Advances in the Catalytic One-Pot Synthesis of Flavonoids and Chromones.

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Mohadeszadeh, Manijeh; Iranshahi, Mehrdad

2017-01-01

Flavonoids and chromones are two important classes of natural products that have various biological properties. During the past 10 years, there has been a significant increase in studies on the one-pot synthesis of flavonoids and chromones as medicinal scaffolds in drug discovery. This review describes the scope, mechanistic properties and regio- and chemo-selectivity features of several recently developed one-pot procedures for the synthesis of substituted chromones and flavonoids that have recently been published. Special importance is placed on the most promising and exciting medicinal applications of flavonoids and chromones. In this review, we discuss the progress on the synthesis of flavonoid and chromone derivatives in the presence of metal catalysts, organocatalysts, solid surfaces, microwave irradiation, acid and base catalysis, etc. For example, flavones can be prepared via the catalytic coordination of palladium complexes in a short time and at a low temperature with a high yield. Additionally, the one-pot synthesis of 2-substituted chromones via metal triflate (Yb(OTf)3) has provided the best result for this type of reaction with a high yield and a high regio and chemoselectivity. Generally, this review proposes the first specific overview of this developing and rapidly expanding field of flavonoid synthesis. We also discuss the mechanisms and advantages and disadvantages of methods for the synthesis of flavonoids and chromones. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Flavonoids act as negative regulators of auxin transport in vivo in arabidopsis

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Brown, D. E.; Rashotte, A. M.; Murphy, A. S.; Normanly, J.; Tague, B. W.; Peer, W. A.; Taiz, L.; Muday, G. K.

2001-01-01

Polar transport of the plant hormone auxin controls many aspects of plant growth and development. A number of synthetic compounds have been shown to block the process of auxin transport by inhibition of the auxin efflux carrier complex. These synthetic auxin transport inhibitors may act by mimicking endogenous molecules. Flavonoids, a class of secondary plant metabolic compounds, have been suggested to be auxin transport inhibitors based on their in vitro activity. The hypothesis that flavonoids regulate auxin transport in vivo was tested in Arabidopsis by comparing wild-type (WT) and transparent testa (tt4) plants with a mutation in the gene encoding the first enzyme in flavonoid biosynthesis, chalcone synthase. In a comparison between tt4 and WT plants, phenotypic differences were observed, including three times as many secondary inflorescence stems, reduced plant height, decreased stem diameter, and increased secondary root development. Growth of WT Arabidopsis plants on naringenin, a biosynthetic precursor to those flavonoids with auxin transport inhibitor activity in vitro, leads to a reduction in root growth and gravitropism, similar to the effects of synthetic auxin transport inhibitors. Analyses of auxin transport in the inflorescence and hypocotyl of independent tt4 alleles indicate that auxin transport is elevated in plants with a tt4 mutation. In hypocotyls of tt4, this elevated transport is reversed when flavonoids are synthesized by growth of plants on the flavonoid precursor, naringenin. These results are consistent with a role for flavonoids as endogenous regulators of auxin transport.

Flavonoids and terpenoids from Croton muscicarpa (Euphorbiaceae)

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Barreto, Milena B.; Gomes, Clêrton L.; Freitas, João Vito B. de; Pinto, Francisco das Chagas L.; Silveira, Edilberto R.; Gramosa, Nilce V.; Torres, Daniela S. Carneiro

2013-01-01

A new sesquiterpene and twelve known compounds comprising eight flavonoids and four terpenoids, were isolated from the leaves, stems, roots and exudate of Croton muscicarpa Müll.. Arg.. Their structures were identified as the terpenoids 6α-methoxy-cyperene, dammaradienol, squalene, acetyl aleuritolic acid and spathulenol, and as the flavonoids retusin, 3,7,4’-trimethoxy kaempferol, ombuine, pachipodol, kaempferol, casticin, 5-hydroxy-3,6,7,4’-tetramethoxyflavone and artemetin. All isolated compounds were characterized based on IR, MS, 1 H and 13 C NMR, including 2D analyses (COSY, HSQC, HMBC, NOESY) and comparison with data from the literature. (author)

Flavonoids and terpenoids from Croton muscicarpa (Euphorbiaceae)

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Barreto, Milena B.; Gomes, Clerton L.; Freitas, Joao Vito B. de; Pinto, Francisco das Chagas L.; Silveira, Edilberto R.; Gramosa, Nilce V., E-mail: nilce@dqoi.ufc.br [Departamento de Quimica Organica e Inorganica, Centro de Ciencias, Universidade Federal do Ceara, Fortaleza (Brazil); Torres, Daniela S. Carneiro [Departamento de Ciencias Biologicas Jequie, Universidade Estadual do Sudoeste da Bahia, Jequie, BA (Brazil)

2013-09-01

A new sesquiterpene and twelve known compounds comprising eight flavonoids and four terpenoids, were isolated from the leaves, stems, roots and exudate of Croton muscicarpa Muell.. Arg.. Their structures were identified as the terpenoids 6{alpha}-methoxy-cyperene, dammaradienol, squalene, acetyl aleuritolic acid and spathulenol, and as the flavonoids retusin, 3,7,4'-trimethoxy kaempferol, ombuine, pachipodol, kaempferol, casticin, 5-hydroxy-3,6,7,4'-tetramethoxyflavone and artemetin. All isolated compounds were characterized based on IR, MS, {sup 1}H and {sup 13}C NMR, including 2D analyses (COSY, HSQC, HMBC, NOESY) and comparison with data from the literature. (author)

Flavonoides e terpenoides de Croton muscicarpa (Euphorbiaceae

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Milena B. Barreto

2013-01-01

Full Text Available A new sesquiterpene and twelve known compounds comprising eight flavonoids and four terpenoids, were isolated from the leaves, stems, roots and exudate of Croton muscicarpa Müll. Arg.. Their structures were identified as the terpenoids 6α-methoxy-cyperene, dammaradienol, squalene, acetyl aleuritolic acid and spathulenol, and as the flavonoids retusin, 3,7,4'-trimethoxy kaempferol, ombuine, pachipodol, kaempferol, casticin, 5-hydroxy-3,6,7,4'-tetramethoxyflavone and artemetin. All isolated compounds were characterized based on IR, MS, ¹H and 13C NMR, including 2D analyses (COSY, HSQC, HMBC, NOESY and comparison with data from the literature.

Flavonoids and terpenoids from Croton muscicarpa (Euphorbiaceae)

Energy Technology Data Exchange (ETDEWEB)

Barreto, Milena B.; Gomes, Clerton L.; Freitas, Joao Vito B. de; Pinto, Francisco das Chagas L.; Silveira, Edilberto R.; Gramosa, Nilce V., E-mail: nilce@dqoi.ufc.br [Departamento de Quimica Organica e Inorganica, Centro de Ciencias, Universidade Federal do Ceara, Fortaleza (Brazil); Torres, Daniela S. Carneiro [Departamento de Ciencias Biologicas Jequie, Universidade Estadual do Sudoeste da Bahia, Jequie, BA (Brazil)

2013-09-01

A new sesquiterpene and twelve known compounds comprising eight flavonoids and four terpenoids, were isolated from the leaves, stems, roots and exudate of Croton muscicarpa Muell.. Arg.. Their structures were identified as the terpenoids 6{alpha}-methoxy-cyperene, dammaradienol, squalene, acetyl aleuritolic acid and spathulenol, and as the flavonoids retusin, 3,7,4'-trimethoxy kaempferol, ombuine, pachipodol, kaempferol, casticin, 5-hydroxy-3,6,7,4'-tetramethoxyflavone and artemetin. All isolated compounds were characterized based on IR, MS, {sup 1}H and {sup 13}C NMR, including 2D analyses (COSY, HSQC, HMBC, NOESY) and comparison with data from the literature. (author)

Flavonoids Are Inhibitors of Human Organic Anion Transporter 1 (OAT1)–Mediated Transport

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An, Guohua; Wang, Xiaodong

2014-01-01

Organic anion transporter 1 (OAT1) has been reported to be involved in the nephrotoxicity of many anionic xenobiotics. As current clinically used OAT1 inhibitors are often associated with safety issues, identifying potent OAT1 inhibitors with little toxicity is of great value in reducing OAT1-mediated drug nephrotoxicity. Flavonoids are a class of polyphenolic compounds with exceptional safety records. Our objective was to evaluate the effects of 18 naturally occurring flavonoids, and some of their glycosides, on the uptake of para-aminohippuric acid (PAH) in both OAT1-expressing and OAT1-negative LLC-PK1 cells. Most flavonoid aglycones produced substantial decreases in PAH uptake in OAT1-expressing cells. Among the flavonoids screened, fisetin, luteolin, morin, and quercetin exhibited the strongest effect and produced complete inhibition of OAT1-mediated PAH uptake at a concentration of 50 μM. Further concentration-dependent studies revealed that both morin and luteolin are potent OAT1 inhibitors, with IC50 values of flavonoid aglycones, all flavonoid glycosides had negligible or small effects on OAT1. In addition, the role of OAT1 in the uptake of fisetin, luteolin, morin, and quercetin was investigated and fisetin was found to be a substrate of OAT1. Taken together, our results indicate that flavonoids are a novel class of OAT1 modulators. Considering the high consumption of flavonoids in the diet and in herbal products, OAT1-mediated flavonoid-drug interactions may be clinically relevant. Further investigation is warranted to evaluate the nephroprotective role of flavonoids in relation to drug-induced nephrotoxicity mediated by the OAT1 pathway. PMID:25002746

Qualitative and quantitative analysis of flavonoids in Sophora tonkinensis by LC/MS and HPLC.

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He, Chang-Ming; Cheng, Zhi-Hong; Chen, Dao-Feng

2013-11-01

To develop analytical methods for the identification and determination of the flavonoids in Sophora tonkinensis for comprehensive quality evaluation. An HPLC-DAD-ESI-MS method was used for the separation and characterization of the flavonoids in S. tonkinensis, and a liquid chromatographic method was employed to simultaneously determine five major active flavonoids in this crude drug. Seventeen flavonoids were identified, among which, seven were unambiguously identified as trifolirhizin, quercetin, formononetin, macckiain, kurarinone, sophoranone, and sophoranochromene by comparing their retention times, and UV and MS spectra with those of the authentic compounds, and the other ten flavonoids were tentatively identified by comparing their UV and MS/MS spectra with those of literature data. Furthermore, five major active flavonoids, including trifolirhizin, quercetin, maackiain, sophoranone, and sophoranochromene were determined in S. tonkinensis. All calibration curves expressed good linearity (r > 0.999 8) within the test ranges, and the recovery from this method was 96.40%-104.43%. The developed HPLC method was successfully applied to quantitatively determine the five flavonoids in seventeen samples of S. tonkinensis. The developed method rapidly characterized the bioactive flavonoids of S. tonkinensis, and could be readily utilized to enhance the quality assurance approaches for this traditional Chinese medicine. Copyright © 2013 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Identification and quantification of flavonoids in yellow grain mutant of rice (Oryza sativa L.).

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Kim, Backki; Woo, Sunmin; Kim, Mi-Jung; Kwon, Soon-Wook; Lee, Joohyun; Sung, Sang Hyun; Koh, Hee-Jong

2018-02-15

Flavonoids are naturally occurring phenolic compounds with potential health-promoting activities. Although anthocyanins and phenolic acids in coloured rice have been investigated, few studies have focused on flavonoids. Herein, we analysed flavonoids in a yellow grain rice mutant using UHPLC-DAD-ESI-Q-TOF-MS, and identified 19 flavonoids by comparing retention times and accurate mass measurements. Among them, six flavonoids, isoorientin, isoorientin 2″-O-glucoside, vitexin 2″-O-glucoside, isovitexin, isoscoparin 2″-O-glucoside and isoscoparin, were isolated and fully identified from the yellow grain rice mutant, and the levels were significantly higher than wild-type, with isoorientin particularly abundant in mutant embryo. Significant differences in total phenolic compounds and antioxidant activity were observed in mutant rice by DPPH, FRAP and TEAC assays. The results suggest that the representative six flavonoids may play an important role in colouration and antioxidant activity of embryo and endosperm tissue. The findings provide insight into flavonoid biosynthesis and the possibility of improving functionality in rice. Copyright © 2017 Elsevier Ltd. All rights reserved.

Flavonoids modify root growth and modulate expression of SHORT-ROOT and HD-ZIP III.

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Franco, Danilo Miralha; Silva, Eder Marques; Saldanha, Luiz Leonardo; Adachi, Sérgio Akira; Schley, Thayssa Rabelo; Rodrigues, Tatiane Maria; Dokkedal, Anne Ligia; Nogueira, Fabio Tebaldi Silveira; Rolim de Almeida, Luiz Fernando

2015-09-01

Flavonoids are a class of distinct compounds produced by plant secondary metabolism that inhibit or promote plant development and have a relationship with auxin transport. We showed that, in terms of root development, Copaifera langsdorffii leaf extracts has an inhibitory effect on most flavonoid components compared with the application of exogenous flavonoids (glycosides and aglycones). These compounds alter the pattern of expression of the SHORT-ROOT and HD-ZIP III transcription factor gene family and cause morpho-physiological alterations in sorghum roots. In addition, to examine the flavonoid auxin interaction in stress, we correlated the responses with the effects of exogenous application of auxin and an auxin transport inhibitor. The results show that exogenous flavonoids inhibit primary root growth and increase the development of lateral roots. Exogenous flavonoids also change the pattern of expression of specific genes associated with root tissue differentiation. These findings indicate that flavonoid glycosides can influence the polar transport of auxin, leading to stress responses that depend on auxin. Copyright © 2015 Elsevier GmbH. All rights reserved.

Bee Pollen Flavonoids as a Therapeutic Agent in Allergic and Immunological Disorders.

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Jannesar, Masoomeh; Sharif Shoushtari, Maryam; Majd, Ahmad; Pourpak, Zahra

2017-06-01

Bee pollen grains, as the male reproductive part of seed-bearing plants contain considerable concentrations of various phytochemicals and nutrients. Since antiquity, people throughout the world used pollens to cure colds, flu, ulcers, premature aging, anemia and colitis. It is now well-documented that some bee pollen secondary metabolites (e.g. flavonoid) may have positive health effects. In recent years, the flavonoids have attracted much interest because of their wide range of biological properties and their beneficial effects on human health. The current review, points out potential therapeutic effects of bee pollen flavonoids as one of the main bee pollen bioactive compounds in allergic and immunological diseases. Due to the fact that some types of flavonoid components in bee pollen have anti-allergic, anti-oxidant and anti-inflammatory properties, bee pollen flavonoids can be excellent candidates for future studies including phytotherapy, molecular pharmacology and substitutes for chemicals used in treating allergic and immunological disorders.

Interaction of flavonoids, the naturally occurring antioxidants with different media: a UV-visible spectroscopic study.

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Naseem, Bushra; Shah, S W H; Hasan, Aurangzeb; Sakhawat Shah, S

2010-04-01

Quantitative parameters for interaction of flavonoids-the naturally occurring antioxidants, with solvents and surfactants are determined using UV-visible absorption spectroscopy. The availability of flavonoids; kaempferol, apigenin, kaempferide and rhamnetin in micelles of sodium dodecyl sulfate (SDS) is reflected in terms of partition coefficient, K(c). Thermodynamic calculations show that the process of transfer of flavonoid molecules to anionic micelles of SDS is energy efficient. A distortion in flavonoid's morphology occurs in case of kaempferol and apigenin in surfactant and water, exhibited in terms of a new band in the UV region of electronic spectra of these flavonoids. The partition coefficients of structurally related flavonoids are correlated with their antioxidant activities. Copyright 2010 Elsevier B.V. All rights reserved.

Flavonoids as Important Molecules of Plant Interactions with the Environment

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Justyna Mierziak

2014-10-01

Full Text Available Flavonoids are small molecular secondary metabolites synthesized by plants with various biological activities. Due to their physical and biochemical properties, they are capable of participating in plants’ interactions with other organisms (microorganisms, animals and other plants and their reactions to environmental stresses. The majority of their functions result from their strong antioxidative properties. Although an increasing number of studies focus on the application of flavonoids in medicine or the food industry, their relevance for the plants themselves also deserves extensive investigations. This review summarizes the current knowledge on the functions of flavonoids in the physiology of plants and their relations with the environment.

Flavonoids in Helichrysum pamphylicum inhibit mammalian type I DNA topoisomerase.

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Topcu, Zeki; Ozturk, Bintug; Kucukoglu, Ozlem; Kilinc, Emrah

2008-01-01

DNA topoisomerases are important targets for cancer chemotherapy. We investigated the effects of a methanolic extract of Helichrysum pamphylicum on mammalian DNA topoisomerase I via in vitro plasmid supercoil relaxation assays. The extracts manifested a considerable inhibition of the enzyme's activity in a dose-dependent manner. We also performed a HPLC analysis to identify the flavonoid content of the H. pamphylicum extract and tested the identified flavonoids; luteolin, luteolin-4-glucoside, naringenin, helichrysinA and isoquercitrin, on DNA topoisomerase I activity. The measurement of the total antioxidant capacity of the flavonoid standards suggested that the topoisomerase inhibition might be correlated with the antioxidant capacity of the plant.

Dietary PUFA and flavonoids as deterrents for environmental pollutants.

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Watkins, Bruce A; Hannon, Kevin; Ferruzzi, Mario; Li, Yong

2007-03-01

Various nutrients and plant-derived phytochemicals are associated with a reduced risk of many diet-related chronic diseases including cardiovascular disease, cancer, diabetes, arthritis and osteoporosis. A common theme that links many chronic diseases is uncontrolled inflammation. The long-chain (LC) omega-3 polyunsaturated fatty acids (PUFA) and flavonoids are known to possess anti-inflammatory actions in cell cultures, animal models and humans. Minimizing the condition of persistent inflammation has been a primary aim for drug development, but understanding how food components attenuate this process is at the nexus for improving the human condition. The prevalence of environmental toxins such as heavy metals and organics that contribute to diminished levels of antioxidants likely aggravates inflammatory states when intakes of omega-3 PUFA and flavonoids are marginal. Scientists at Purdue University have formed a collaboration to better understand the metabolism and physiology of flavonoids. This new effort is focused on determining how candidate flavonoids and their metabolites affect gene targets of inflammation in cell culture and animal models. The challenge of this research is to understand how LC omega-3 PUFA and flavonoids affect the biology of inflammation. The goal is to determine how nutrients and phytochemicals attenuate chronic inflammation associated with a number of diet-related diseases that occur throughout the life cycle. The experimental approach involves molecular, biochemical and physiological endpoints of aging, cancer, obesity and musculoskeletal diseases. Examples include investigations on the combined effects of PUFA and cyanidins on inflammatory markers in cultures of human cancer cells. The actions of catechins and PUFA on muscle loss and osteopenia are being studied in a rodent model of disuse atrophy to explain how muscle and bone communicate to prevent tissue loss associated with injury, disease and aging. The purpose of this review is

Tobacco randomly inserted tt8 differenly enhance light signals and flavonoid accumulation

International Nuclear Information System (INIS)

Sompornpailin, K.; Kanthang, S.

2015-01-01

The individual lines of tobacco over-expressing TT8, a bHLH gene, were constructed and cultured under tissue culture condition radiating with photosynthetically activation radiation (PAR) or PAR+UVA. They were compared to wild type (WT). Leaf of treated plants was extracted and analyzed for flavonoid accumulations using a spectrophotometer. The extract of TT8 plants significantly contained flavone, flavonol and anthocyanin level, higher than the WT extract did. The petal extracts of mature transgenic under PAR had a similar absorbance profile of each substance, but these extracts had higher flavonoid contents than the leaf extracts did. All flavonoid subgroups and p-coumaric acid biosynthesis were significantly enhanced after the additional UVA radiation to plant. This UVA condition slightly stimulated an accumulation of these substances in normal plant. Some transgenic greatly increased flavonoid accumulation in responding to PAR+UVA, but the others were slightly different compared to WT. The distinct insertion site is directly affected TT8 gene expression. Transgenic seeds had a dark brown color more than WT seed, which indicated high content of polymer flavonoids (proanthocyanins). This over-expressing TT8 in transgenic tobacco may directly or indirectly enhance the signal transductions of PAR and UVA and raise up flavonoid accumulation. (author)

The surge of flavonoids as novel, fine regulators of cardiovascular Cav channels.

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Fusi, Fabio; Spiga, Ottavia; Trezza, Alfonso; Sgaragli, Giampietro; Saponara, Simona

2017-02-05

Ion channels underlie a wide variety of physiological processes that involve rapid changes in cell dynamics, such as cardiac and vascular smooth muscle contraction. Overexpression or dysfunction of these membrane proteins are the basis of many cardiovascular diseases that represent the leading cause of morbidity and mortality for human beings. In the last few years, flavonoids, widely distributed in the plant kingdom, have attracted the interest of many laboratories as an emerging class of fine ion, in particular Ca v , channels modulators. Pieces of in vitro evidence for direct as well as indirect effects exerted by various flavonoids on ion channel currents are now accumulating in the scientific literature. This activity may be responsible, at least in part, for the beneficial and protective effects of dietary flavonoids toward cardiovascular diseases highlighted in several epidemiological studies. Here we examine numerous studies aimed at analysing this feature of flavonoids, focusing on the mechanisms that promote their sometimes controversial activities at cardiovascular Ca v channels. New methodological approaches, such as molecular modelling and docking to Ca v 1.2 channel α 1c subunit, used to elucidate flavonoids intrinsic mechanism of action, are introduced. Moreover, flavonoid-membrane interaction, bioavailability, and antioxidant activity are taken into account and discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

Dynamic changes of flavonoids in Actinidia valvata leaves at different growing stages measured by HPLC-MS/MS.

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DU, Qiao-Hui; Zhang, Qiao-Yan; Han, Ting; Jiang, Yi-Ping; Peng, Cheng; Xin, Hai-Liang

2016-01-01

Flavonoids are a large group of phenolic secondary metabolites havinga wide range of biochemical and pharmacological effects. Quantitative analysis of flavonoid profiles in the genus Actinidia, which has not been intensively conducted, is useful to a better understanding of the pattern and distribution of flavonoids. In the present work, a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method was developed to profile the flavonoids, which was then used to determine the dynamic change of 17 biologically active flavonoids in the leaves of Actinidia valvata at the main growing stages, including glucuronides and acylated di- and triglycosides of flavonoids. The contents of flavonoid triglycosides were significantly higher than other flavonoids. The highest concentrations of kaemperol glycosides were observed in June, while other flavonoids showed highest concentrations in October. On the other hand, the contents of four isorhamnetin glycosides were increased sharply in September to October. The flavonoid profiles seem to be related to temperature, UV-B, and water deficit. Further studies are required to examine the functions of flavonoids in the Actinidia valvata and the underlying molecular mechanisms of actions. Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Flavonoid electrochemistry: a review on the electroanalytical applications

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Eric S. Gil

2013-05-01

Full Text Available Flavonoids are polyphenolic compounds widespread in vegetal kingdom. They present a C-15 skeleton, which is divided into three units A, B and C. Unit C is an oxygen containing heterocyclic, whose oxidation state and saturation level define major subclasses. Units A and B are aromatic rings, in which four major types of substituents, i. e. hydroxyl, methoxyl, prenyl and glycosides, lead to over 8000 different flavonoids. The great healthy-protecting value of these phytochemical biomarkers has attracted the attention of scientific community. Their main biological actions include anticancer and anti-inflammatory properties, which are strictly linked to antioxidant activities. So that, electroanalysis have been extensively applied on mechanistic studies and also for analytical determinations. This review presents the state of the art regarding the main applications of electroanalysis on the flavonoid research. The approaches on redox behavior characterization leading to a better understanding of structure antioxidant activity relationships are highlighted.

Flavonoid electrochemistry: a review on the electroanalytical applications

Directory of Open Access Journals (Sweden)

Eric S. Gil

2013-06-01

Full Text Available Flavonoids are polyphenolic compounds widespread in vegetal kingdom. They present a C-15 skeleton, which is divided into three units A, B and C. Unit C is an oxygen containing heterocyclic, whose oxidation state and saturation level define major subclasses. Units A and B are aromatic rings, in which four major types of substituents, i. e. hydroxyl, methoxyl, prenyl and glycosides, lead to over 8000 different flavonoids. The great healthy-protecting value of these phytochemical biomarkers has attracted the attention of scientific community. Their main biological actions include anticancer and anti-inflammatory properties, which are strictly linked to antioxidant activities. So that, electroanalysis have been extensively applied on mechanistic studies and also for analytical determinations. This review presents the state of the art regarding the main applications of electroanalysis on the flavonoid research. The approaches on redox behavior characterization leading to a better understanding of structure antioxidant activity relationships are highlighted.

Diamond-like nanoparticles influence on flavonoids transport: molecular modelling

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Plastun, Inna L.; Agandeeva, Ksenia E.; Bokarev, Andrey N.; Zenkin, Nikita S.

2017-03-01

Intermolecular interaction of diamond-like nanoparticles and flavonoids is investigated by numerical simulation. Using molecular modelling by the density functional theory method, we analyze hydrogen bonds formation and their influence on IR - spectra and structure of molecular complex which is formed due to interaction between flavonoids and nanodiamonds surrounded with carboxylic groups. Enriched adamantane (1,3,5,7 - adamantanetetracarboxylic acid) is used as an example of diamond-like nanoparticles. Intermolecular forces and structure of hydrogen bonds are investigated. IR - spectra and structure parameters of quercetin - adamantanetetracarboxylic acid molecular complex are obtained by numerical simulation using the Gaussian software complex. Received data coincide well with experimental results. Intermolecular interactions and hydrogen bonding structure in the obtained molecular complex are examined. Possibilities of flavonoids interaction with DNA at the molecular level are also considered.

Identification and quantification and antioxidant activity of flavonoids in different strains of silk cocoon, Bombyx mori.

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Napavichayanun, Supamas; Lutz, Oliver; Fischnaller, Martin; Jakschitz, Thomas; Bonn, Günther; Aramwit, Pornanong

2017-10-01

Silk cocoon is produced from silkworm (Bombyx mori) to protect itself from outer environment. Various strains of cocoon contain different forms and amounts of flavonoids, which may affect on their antioxidant activity. Moreover, the extraction method would influence the amount of flavonoids extracted. Therefore, the objectives of this study were to identify and quantify the flavonoids in 3 strains of bivoltine Bombyx mori silk cocoon (Chul 1/1; white cocoon, Chul 3/2; greenish cocoon, and Chul 4/2; yellow cocoon) extracted by 6 different solvents including acetone, ethyl acetate, dimethyl sulfoxide (DMSO), ethanol, methanol, and purified water. The flavonoids extracted were identified and quantified by liquid chromatography-mass spectrometry (LC-MS). The antioxidant activity of flavonoids extracted was also investigated by visible spectroscopy at 517 nm. The results showed that Chul 3/2 silk cocoon contained the highest amount of flavonoids. Purified water seemed to be the best solvent that preserved most antioxidant activity of the flavonoids extracted. Flavonoids in Chul 1/1 and Chul 4/2 silk cocoon were rarely found, however they contained some antioxidant activities. The data from this study can provide basic information for flavonoid extraction from silk cocoon which can also apply for other flavonoid-containing natural biomaterials. Copyright © 2017 Elsevier Inc. All rights reserved.

Utilizing of Square Wave Voltammetry to Detect Flavonoids in the Presence of Human Urine

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Rene Kizek

2007-10-01

Full Text Available About biological affecting of flavonoids on animal organisms is known less,thus we selected flavonoids, flavanones and flavones, and their glycosides, which wereexamined as potential inducers of cytochrome(s P450 when administrated by gavages intoexperimental male rats. The study was focused on induction of CYP1A1, the majorcytochrome P450 involved in carcinogen activation. The data obtained demonstrate thenecessity of taking into account not only ability of flavonoids to bind to Ah receptor(induction factor but also to concentrate on their distribution and metabolism (includingcolon microflora in the body. After that we examined certain flavonoids as potential inducers of cytochrome P450, we wanted to suggest and optimize suitable electrochemical technique for determination of selected flavonoids (quercetin, quercitrin, rutin, chrysin and diosmin in body liquids. For these purposes, we selected square wave voltannetry using carbon paste electrode. Primarily we aimed on investigation of their basic electrochemical behaviour. After that we have optimized frequency, step potential and supporting electrolyte. Based on the results obtained, we selected the most suitable conditions for determination of the flavonoids as follows: frequency 180 Hz, step potential 1.95 mV/s and phosphate buffer of pH 7 as supporting electrolyte. Detection limits (3 S/N of the flavonoids were from units to tens of nM except diosmin, where the limit were higher than μM. In addition, we attempted to suggest a sensor for analysis of flavonoids in urine. It clearly follows from the results obtained that flavonoids can be analysed in the presence of animal urine, because urine did not influence much the signals of flavonoids (recoveries of the signals were about 90 %.

The flavonoid pathway in tomato seedlings: transcript abundance and the modeling of metabolite dynamics.

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Marian Groenenboom

Full Text Available Flavonoids are secondary metabolites present in all terrestrial plants. The flavonoid pathway has been extensively studied, and many of the involved genes and metabolites have been described in the literature. Despite this extensive knowledge, the functioning of the pathway in vivo is still poorly understood. Here, we study the flavonoid pathway using both experiments and mathematical models. We measured flavonoid metabolite dynamics in two tissues, hypocotyls and cotyledons, during tomato seedling development. Interestingly, the same backbone of interactions leads to very different accumulation patterns in the different tissues. Initially, we developed a mathematical model with constant enzyme concentrations that described the metabolic networks separately in both tissues. This model was unable to fit the measured flavonoid dynamics in the hypocotyls, even if we allowed unrealistic parameter values. This suggested us to investigate the effect of transcript abundance on flavonoid accumulation. We found that the expression of candidate flavonoid genes varies considerably with time. Variation in transcript abundance results in enzymatic variation, which could have a large effect on metabolite accumulation. Candidate transcript abundance was included in the mathematical model as representative for enzyme concentration. We fitted the resulting model to the flavonoid dynamics in the cotyledons, and tested it by applying it to the data from hypocotyls. When transcript abundance is included, we are indeed able to explain flavonoid dynamics in both tissues. Importantly, this is possible under the biologically relevant restriction that the enzymatic properties estimated by the model are conserved between the tissues.

Ultrasound-Assisted Extraction of Total Flavonoids from Corn Silk and Their Antioxidant Activity

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Ling-Li Zheng

2016-01-01

Full Text Available Object. Ultrasound-assisted extraction of total flavonoids from corn silk and their antioxidant activities were studied. Methods. Response surface methodology was adopted to optimize the extraction conditions and antioxidant activities of the extracted total flavonoids were detected through ferric reducing antioxidant power (FRAP assay. Results. Through a three-level, three-variable Box-Behnken design of response surface methodology (RSM adopting yield as response, the optimal conditions were determined as follows: ultrasonic power 500 W, extraction time 20 min, material solvent ratio 1 : 20, and ethanol concentration 30%. Under the optimum conditions, the extraction yield of total flavonoids was 1.13%. FRAP value of total flavonoids extracted from corn silk was 467.59 μmol/L. Conclusion. The total flavonoids of corn silk could be developed as food natural antioxidant reagents.

Flavonoids of Steganotaenia araliacea

CSIR Research Space (South Africa)

Omolo, JJ

2014-01-01

Full Text Available Communication www.usa-journals.com Omolo, et al., 2014: Vol 2(8) 52 ajrc.journal@gmail.com Flavonoids of Steganotaenia araliacea 1,2,3*Omolo J.J., 2Maharaj V., 2... Communication www.usa-journals.com Omolo, et al., 2014: Vol 2(8) 53 ajrc.journal@gmail.com Introduction The Tanga Aids Working Group (TAWG) in collaboration...

Catalase inhibition an anti cancer property of flavonoids: A kinetic and structural evaluation.

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Majumder, Debashis; Das, Asmita; Saha, Chabita

2017-11-01

Flavonoids are dietary polyphenols that present abundantly in fruits and vegetables. Flavonoids have inhibitory effects on enzymes and catalase is one among them. Catalase is a common enzyme ubiquitously found in all living organisms exposed to oxygen. It catalyzes the decomposition of hydrogen peroxide to water and oxygen (2H 2 O 2 →2H 2 O+O 2 ) . Inhibition of pure and cellular catalase from K562 cells by flavonoids was similar and exhibited the following efficacy; Myrecetin>Quercetin>Kaempferol and Quercetin>Luteolin>Apigenin demonstrating structure activity relationship. Circular Dichroism (CD) spectra have shown distinct loss in α-helical structure of the catalase on interaction with the flavonoids. All flavonoids inhibited the catalase activity by uncompetitive mechanism. The K m and V max values of pure catalase were observed to be 294mM -1 and 0.222mM -1 s -1 respectively and on inhibition with myrecetin the values decreased to a minimum of 23mM -1 and 0.014mM -1 s -1 respectively. Inhibition of catalase will directly results in increased production of Reactive Oxygen Species (ROS) and pro-oxidant property of flavonoids. This inhibition was reversed in presence of Cu 2+ ions because of the chelating affect of flavonoids. Copyright © 2017 Elsevier B.V. All rights reserved.

3D-QSAR and docking studies of flavonoids as potent Escherichia coli inhibitors

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Fang, Yajing; Lu, Yulin; Zang, Xixi; Wu, Ting; Qi, XiaoJuan; Pan, Siyi; Xu, Xiaoyun

2016-01-01

Flavonoids are potential antibacterial agents. However, key substituents and mechanism for their antibacterial activity have not been fully investigated. The quantitative structure-activity relationship (QSAR) and molecular docking of flavonoids relating to potent anti-Escherichia coli agents were investigated. Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were developed by using the pIC50 values of flavonoids. The cross-validated coefficient (q2) values for CoMFA (0.743) and for CoMSIA (0.708) were achieved, illustrating high predictive capabilities. Selected descriptors for the CoMFA model were ClogP (logarithm of the octanol/water partition coefficient), steric and electrostatic fields, while, ClogP, electrostatic and hydrogen bond donor fields were used for the CoMSIA model. Molecular docking results confirmed that half of the tested flavonoids inhibited DNA gyrase B (GyrB) by interacting with adenosine-triphosphate (ATP) pocket in a same orientation. Polymethoxyl flavones, flavonoid glycosides, isoflavonoids changed their orientation, resulting in a decrease of inhibitory activity. Moreover, docking results showed that 3-hydroxyl, 5-hydroxyl, 7-hydroxyl and 4-carbonyl groups were found to be crucial active substituents of flavonoids by interacting with key residues of GyrB, which were in agreement with the QSAR study results. These results provide valuable information for structure requirements of flavonoids as antibacterial agents. PMID:27049530

The role of metabolism (and the microbiome) in defining the clinical efficacy of dietary flavonoids.

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Cassidy, Aedín; Minihane, Anne-Marie

2017-01-01

At a population level, there is growing evidence of the beneficial effects of dietary flavonoids on health. However, there is extensive heterogeneity in the response to increased intake, which is likely mediated via wide interindividual variability in flavonoid absorption and metabolism. Flavonoids are extensively metabolized by phase I and phase II metabolism (which occur predominantly in the gastrointestinal tract and liver) and colonic microbial metabolism. A number of factors, including age, sex, and genotype, may affect these metabolic processes. In addition, food composition and flavonoid source are likely to affect bioavailability, and emerging data suggest a critical role for the microbiome. This review will focus on the current knowledge for the main subclasses of flavonoids, including anthocyanins, flavonols, flavan-3-ols, and flavanones, for which there is growing evidence from prospective studies of beneficial effects on health. The identification of key factors that govern metabolism and an understanding of how the differential capacity to metabolize these bioactive compounds affect health outcomes will help establish how to optimize intakes of flavonoids for health benefits and in specific subgroups. We identify research areas that need to be addressed to further understand important determinants of flavonoid bioavailability and metabolism and to advance the knowledge base that is required to move toward the development of dietary guidelines and recommendations for flavonoids and flavonoid-rich foods.

Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adults.

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Engler, Mary B; Engler, Marguerite M; Chen, Chung Y; Malloy, Mary J; Browne, Amanda; Chiu, Elisa Y; Kwak, Ho-Kyung; Milbury, Paul; Paul, Steven M; Blumberg, Jeffrey; Mietus-Snyder, Michele L

2004-06-01

Dark chocolate derived from the plant (Theobroma cacao) is a rich source of flavonoids. Cardioprotective effects including antioxidant properties, inhibition of platelet activity, and activation of endothelial nitric oxide synthase have been ascribed to the cocoa flavonoids. To investigate the effects of flavonoid-rich dark chocolate on endothelial function, measures of oxidative stress, blood lipids, and blood pressure in healthy adult subjects. The study was a randomized, double-blind, placebo-controlled design conducted over a 2 week period in 21 healthy adult subjects. Subjects were randomly assigned to daily intake of high-flavonoid (213 mg procyanidins, 46 mg epicatechin) or low-flavonoid dark chocolate bars (46 g, 1.6 oz). High-flavonoid chocolate consumption improved endothelium-dependent flow-mediated dilation (FMD) of the brachial artery (mean change = 1.3 +/- 0.7%) as compared to low-flavonoid chocolate consumption (mean change = -0.96 +/- 0.5%) (p = 0.024). No significant differences were noted in the resistance to LDL oxidation, total antioxidant capacity, 8-isoprostanes, blood pressure, lipid parameters, body weight or body mass index (BMI) between the two groups. Plasma epicatechin concentrations were markedly increased at 2 weeks in the high-flavonoid group (204.4 +/- 18.5 nmol/L, p < or = 0.001) but not in the low-flavonoid group (17.5 +/- 9 nmol/L, p = 0.99). Flavonoid-rich dark chocolate improves endothelial function and is associated with an increase in plasma epicatechin concentrations in healthy adults. No changes in oxidative stress measures, lipid profiles, blood pressure, body weight or BMI were seen.

Separation, purification and identification of flavonoid glycosides using reversed phase hplc

International Nuclear Information System (INIS)

Hasan, A.; Khan, M.A.

2002-01-01

Optimal high performance liquid chromatography (HPLC) separation conditions and semi-preparative scale isolation of flavonoid glycosides from three plant species namely Vitex nagunda, Rubus ulmifolious and Malotus philipensis is reported. Identification of purified flavonoid glycoside was achieved using spiking technique in HPLC. (author)

Novel Investigations of Flavonoids as Chemopreventive Agents for Hepatocellular Carcinoma

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Chen-Yi Liao

2015-01-01

Full Text Available We would like to highlight the application of natural products to hepatocellular carcinoma (HCC. We will focus on the natural products known as flavonoids, which target this disease at different stages of hepatocarcinogenesis. In spite of the use of chemotherapy and radiotherapy in treating HCC, patients with HCC still face poor prognosis because of the nature of multidrug resistance and toxicity derived from chemotherapy and radiotherapy. Flavonoids can be found in many vegetables, fruits, and herbal medicines that exert their different anticancer effects via different intracellular signaling pathways and serve as antioxidants. In this review, we will discuss seven common flavonoids that exert different biological effects against HCC via different pathways.

Biogenesis of C-Glycosyl Flavones and Profiling of Flavonoid Glycosides in Lotus (Nelumbo nucifera)

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Li, Shan-Shan; Wu, Jie; Chen, Li-Guang; Du, Hui; Xu, Yan-Jun; Wang, Li-Jing; Zhang, Hui-Jin; Zheng, Xu-Chen; Wang, Liang-Sheng

2014-01-01

Flavonoids in nine tissues of Nelumbo nucifera Gaertner were identified and quantified by high-performance liquid chromatography with diode array detector (HPLC-DAD) and HPLC-electrospray ionization-mass spectrometry (HPLC-ESI-MSn). Thirty-eight flavonoids were identified; eleven C-glycosides and five O-glycosides were discovered for the first time in N. nucifera. Most importantly, the C-glycosyl apigenin or luteolin detected in lotus plumules proved valuable for deep elucidation of flavonoid composition in lotus tissues and for further utilization as functional tea and medicine materials. Lotus leaves possessed the significantly highest amount of flavonoids (2.06E3±0.08 mg 100 g−1 FW) and separating and purifying the bioactive compound, quercetin 3-O-glucuronide, from leaves showed great potential. In contrast, flavonoids in flower stalks, seed coats and kernels were extremely low. Simultaneously, the optimal picking time was confirmed by comparing the compound contents in five developmental phases. Finally, we proposed the putative flavonoid biosynthesis pathway in N. nucifera. PMID:25279809

Multiobjective optimization of a steering linkage

Energy Technology Data Exchange (ETDEWEB)

Sleesonsom, S.; Bureerat, S. [Sustainable and Infrastructure Research and Development Center, Dept. of Mechanical Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen (Thailand)

2016-08-15

In this paper, multi-objective optimization of a rack-and-pinion steering linkage is proposed. This steering linkage is a common mechanism used in small cars with three advantages as it is simple to construct, economical to manufacture, and compact and easy to operate. In the previous works, many researchers tried to minimize a steering error but minimization of a turning radius is somewhat ignored. As a result, a multi-objective optimization problem is assigned to simultaneously minimize a steering error and a turning radius. The design variables are linkage dimensions. The design problem is solved by the hybrid of multi-objective population-based incremental learning and differential evolution with various constraint handling schemes. The new design strategy leads to effective design of rack-and-pinion steering linkages satisfying both steering error and turning radius criteria.

Multiobjective optimization of a steering linkage

International Nuclear Information System (INIS)

Sleesonsom, S.; Bureerat, S.

2016-01-01

In this paper, multi-objective optimization of a rack-and-pinion steering linkage is proposed. This steering linkage is a common mechanism used in small cars with three advantages as it is simple to construct, economical to manufacture, and compact and easy to operate. In the previous works, many researchers tried to minimize a steering error but minimization of a turning radius is somewhat ignored. As a result, a multi-objective optimization problem is assigned to simultaneously minimize a steering error and a turning radius. The design variables are linkage dimensions. The design problem is solved by the hybrid of multi-objective population-based incremental learning and differential evolution with various constraint handling schemes. The new design strategy leads to effective design of rack-and-pinion steering linkages satisfying both steering error and turning radius criteria

Measurement of food flavonoids by high-performance liquid chromatography: A review.

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Merken, H M; Beecher, G R

2000-03-01

The flavonoids are plant polyphenols found frequently in fruits, vegetables, and grains. Divided into several subclasses, they include the anthocyanidins, pigments chiefly responsible for the red and blue colors in fruits, fruit juices, wines, and flowers; the catechins, concentrated in tea; the flavanones and flavanone glycosides, found in citrus and honey; and the flavones, flavonols, and flavonol glycosides, found in tea, fruits, vegetables, and honey. Known for their hydrogen-donating antioxidant activity as well as their ability to complex divalent transition metal cations, flavonoids are propitious to human health. Computer-controlled high-performance liquid chromatography (HPLC) has become the analytical method of choice. Many systems have been developed for the detection and quantification of flavonoids across one, two, or three subclasses. A summary of the various HPLC and sample preparation methods that have been employed to quantify individual flavonoids within a subclass or across several subclasses are tabulated in this review.

A New Database Facilitates Characterization of Flavonoid Intake, Sources, and Positive Associations with Diet Quality among US Adults.

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Sebastian, Rhonda S; Wilkinson Enns, Cecilia; Goldman, Joseph D; Martin, Carrie L; Steinfeldt, Lois C; Murayi, Theophile; Moshfegh, Alanna J

2015-06-01

Epidemiologic studies demonstrate inverse associations between flavonoid intake and chronic disease risk. However, lack of comprehensive databases of the flavonoid content of foods has hindered efforts to fully characterize population intakes and determine associations with diet quality. Using a newly released database of flavonoid values, this study sought to describe intake and sources of total flavonoids and 6 flavonoid classes and identify associations between flavonoid intake and the Healthy Eating Index (HEI) 2010. One day of 24-h dietary recall data from adults aged ≥ 20 y (n = 5420) collected in What We Eat in America (WWEIA), NHANES 2007-2008, were analyzed. Flavonoid intakes were calculated using the USDA Flavonoid Values for Survey Foods and Beverages 2007-2008. Regression analyses were conducted to provide adjusted estimates of flavonoid intake, and linear trends in total and component HEI scores by flavonoid intake were assessed using orthogonal polynomial contrasts. All analyses were weighted to be nationally representative. Mean intake of flavonoids was 251 mg/d, with flavan-3-ols accounting for 81% of intake. Non-Hispanic whites had significantly higher (P empty calories increased (P < 0.001) across flavonoid intake quartiles. A new database that permits comprehensive estimation of flavonoid intakes in WWEIA, NHANES 2007-2008; identification of their major food/beverage sources; and determination of associations with dietary quality will lead to advances in research on relations between flavonoid intake and health. Findings suggest that diet quality, as measured by HEI, is positively associated with flavonoid intake. © 2015 American Society for Nutrition.

Flavonoids as Chemopreventive and Therapeutic Agents Against Lung Cancer

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Albert Cabrera

2014-05-01

Full Text Available The objective of the present review is to study the relationship between flavonoids and lung cancer, proposing that their regular consumption in Western diets could be beneficial for protecting patients against lung cancer. An extensive search of the scientific literature was performed in the following electronic specialized databases (PubMed central (PMC-NBCI, Elsevier Journal, SciELO Spain, Scirus, Science Direct, including studies in animals, cells, and humans, in order to establish the effect of flavonoids in the prevention and development of lung cancer. Although in vitro and animal studies show the potential ability of flavonoids to act against different types of cancers, especially against lung cancers, the diverse results reported within epidemiological studies, together with the lack of experiments in humans, are the major factors in limiting making dietary recommendations based on scientific evidence for the management of patients with lung cancer. Therefore, the authors of the present study recommend following the dietary health practice guidelines which promotes the consumption of food enriched in flavonoids and reflects the current state of knowledge of an effective and appropriate diet in lung cancer patients.Erratum in: Rev Esp Nutr Hum Diet. 2013;17(2:91-92Link: http://www.renhyd.org/index.php/renhyd/article/view/6/17

SERS study of riboflavin on green-synthesized silver nanoparticles prepared by reduction using different flavonoids: What is the role of flavonoid used?

Science.gov (United States)

Švecová, Marie; Ulbrich, Pavel; Dendisová, Marcela; Matějka, Pavel

2018-04-01

Spectroscopy of surface-enhanced Raman scattering (SERS) is nowadays widely used in the field of bio-science and medicine. These applications require new enhancing substrates with special properties. They should be non-toxic, environmentally friendly and (bio-) compatible with examined samples. Flavonoids are natural antioxidants with many positive effects on human health. Simultaneously, they can be used as reducing agent in preparation procedure of plasmonic enhancing substrate for SERS spectroscopy. The best amplifiers of Raman vibrational spectroscopic signal are generally silver nanoparticles (AgNPs). In this study, several flavonoids (forming a logical set) were used as reducing agent in AgNPs preparation procedures. Reactivity of 10 structurally arranged flavonoids (namely flavone, chrysin, apigenin, luteolin, tricetin, 3-hydroxyflavone, galangin, kaempferol, quercetin and myricetin) was compared and SERS-activity of prepared AgNPs was tested using model analyte riboflavin. Riboflavin was detected down to concentration 10-9 mol/l.

Influence of Flavonoids on Mechanism of Modulation of Insulin Secretion.

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Soares, Juliana Mikaelly Dias; Pereira Leal, Ana Ediléia Barbosa; Silva, Juliane Cabral; Almeida, Jackson R G S; de Oliveira, Helinando Pequeno

2017-01-01

The development of alternatives for insulin secretion control in vivo or in vitro represents an important aspect to be investigated. In this direction, natural products have been progressively explored with this aim. In particular, flavonoids are potential candidates to act as insulin secretagogue. To study the influence of flavonoid on overall modulation mechanisms of insulin secretion. The research was conducted in the following databases and platforms: PubMed, Scopus, ISI Web of Knowledge, SciELO, LILACS, and ScienceDirect, and the MeSH terms used for the search were flavonoids, flavones, islets of Langerhans, and insulin-secreting cells. Twelve articles were included and represent the basis of discussion on mechanisms of insulin secretion of flavonoids. Papers in ISI Web of Knowledge were in number of 1, Scopus 44, PubMed 264, ScienceDirect 511, and no papers from LILACS and SciELO databases. According to the literature, the majority of flavonoid subclasses can modulate insulin secretion through several pathways, in an indication that corresponding molecule is a potential candidate for active materials to be applied in the treatment of diabetes. The action of natural products on insulin secretion represents an important investigation topic due to their importance in the diabetes controlIn addition to their typical antioxidant properties, flavonoids contribute to the insulin secretionThe modulation of insulin secretion is induced by flavonoids according to different mechanisms. Abbreviations used: K ATP channels: ATP-sensitive K + channels, GLUT4: Glucose transporter 4, ERK1/2: Extracellular signal-regulated protein kinases 1 and 2, L-VDCCs: L-type voltage-dependent Ca +2 channels, GLUT1: Glucose transporter 1, AMPK: Adenosine monophosphate-activated protein kinase, PTP1B: Protein tyrosine phosphatase 1B, GLUT2: Glucose transporter 2, cAMP: Cyclic adenosine monophosphate, PKA: Protein kinase A, PTK: Protein tyrosine kinase, CaMK II: Ca 2+ /calmodulin

Acylated flavonol tri- and tetraglycosides in the flavonoid metabolome of Cladrastis kentukea (Leguminosae).

Science.gov (United States)

Kite, Geoffrey C; Rowe, Emily R; Lewis, Gwilym P; Veitch, Nigel C

2011-04-01

The foliar metabolome of Cladrastis kentukea (Leguminosae) contains a complex mixture of flavonoids including acylated derivatives of the 3-O-rhamnosyl(1→2)[rhamnosyl(1→6)]-galactosides of kaempferol and quercetin and their 7-O-rhamnosides, together with an array of non-acylated kaempferol and quercetin di-, tri- and tetraglycosides. Thirteen of the acylated flavonoids, 12 of which had not been reported previously, were characterised by spectroscopic and chemical methods. Eight of these were the four isomers of kaempferol 3-O-α-l-rhamnopyranosyl(1→2)[α-l-rhamnopyranosyl(1→6)]-(3/4-O-E/Z-p-coumaroyl-β-d-galactopyranoside) and their 7-O-α-l-rhamnopyranosides, and three were isomers of quercetin 3-O-α-l-rhamnopyranosyl(1→2)[α-l-rhamnopyranosyl(1→6)]-(3/4-O-E/Z-p-coumaroyl-β-d-galactopyranoside) - the remaining 4Z isomer was identified by LC-UV-MS analysis of a crude extract. The final two acylated flavonoids characterised by NMR were the 3E and 4E isomers of kaempferol 3-O-α-l-rhamnopyranosyl(1→2)[α-l-rhamnopyranosyl(1→6)]-(3/4-O-E-feruloyl-β-d-galactopyranoside)-7-O-α-l-rhamnopyranoside while the 3Z and 4Z isomers were again detected by LC-UV-MS. Using the observed fragmentation behaviour of the isolated compounds following a variety of MS experiments, a further 18 acylated flavonoids were given tentative structures by LC-MS analysis of a crude extract. Acylated flavonoids were absent from the flowers of C. kentukea, which contained an array of non-acylated kaempferol and quercetin glycosides. Immature fruits contained kaempferol 3-O-α-rhamnopyranosyl(1→2)[α-rhamnopyranosyl(1→6)]-β-galactopyranoside and its 7-O-α-rhamnopyranoside as the major flavonoids with acylated flavonoids, different from those in the leaves, only present as minor constituents. The presence of acylated flavonoids distinguishes the foliar flavonoid metabolome of C. kentukea from that of a closely related legume, Styphnolobium japonicum, which contains a similar

In vitro biotransformation of flavonoids by rat liver microsomes

DEFF Research Database (Denmark)

Nielsen, S. E.; Breinholt, V.; Justesen, U.

1998-01-01

1. Sixteen naturally occurring flavonoids were investigated as substrates for cytochrome P450 in uninduced and Aroclor 1254-induced rat liver microsomes. Naringenin, hesperetin, chrysin, apigenin, tangeretin, kaempferol, galangin and tamarixetin were all metabolized extensively by induced rat liver...... pathway leading to the corresponding 3',4'-dihydroxylated flavonoids either by hydroxylation or demethylation. Structural requirements for microsomal hydroxylation appeared to be a single or no hydroxy group on the B-ring of the flavan nucleus. The presence of two or more hydroxy groups on the B......-ring seemed to prevent further hydroxylation. The results indicate that demethylation only occurs in the B-ring when the methoxy group is positioned at C-4'-, and not at the C-3'-position. 3. The CYP1A isozymes were found to be the main enzymes involved in flavonoid hydroxylation, whereas other cytochrome P...

Fast Separation and Determination of Flavonoids in Honey Samples by Capillary Zone Electrophoresis

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Jian-Qiu Tu

2017-03-01

Full Text Available Flavonoids have crucial applications in the biological and physiological fields. Honey, as an important sweet food made by bees, is rich in flavonoids. In this paper, the analytical method for flavonoids determination in different sorts of honey from different geographical locations was developed by capillary zone electrophoresis with direct ultraviolet detection. With a running buffer (borate, 20 mmol l−1 at pH of 8.4, four typical flavonoids, rutin, quercetin, kaempferol and myricetin, were separated in five minutes under a applied potential of 25 kV. A linear relationship within the range of 2.0 – 500 mg l−1 was found for these four kinds of flavonoids. Moreover, the detection limits ranged from 1.17 to 1.76 mg l−1. The recoveries lie in the range between 80 % – 107 %. The developed method was then used in the separation and determination of flavonoids in real honey samples collected from 12 geographical locations in the Henan Province of China. Rutin was detected in six, and quercetin in eight honey samples, which may be the markers for the identification of honey from different geographical origins.

Flavonoids biosynthesis in plants and its further analysis by capillary electrophoresis.

Science.gov (United States)

Singh, Baljinder; Kumar, Ashwini; Malik, Ashok Kumar

2017-03-01

Flavonoids represent an important bioactive component in plants. Accumulation of flavonoids often occurs in plants subjected to abiotic stresses, including the adaptation of plants to the environment and in overcoming their stress conditions. This fact makes their analysis and determination an attractive field in food science since they can give interesting information on the quality and safety of foods. In this study, we discuss reports on plants flavonoids biosynthesis against abiotic stresses and advances in analytical capillary electrophoresis used for their identification and quantification in plants. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Therapeutic potential of flavonoids in inflammatory bowel disease: A comprehensive review.

Science.gov (United States)

Salaritabar, Ali; Darvishi, Behrad; Hadjiakhoondi, Farzaneh; Manayi, Azadeh; Sureda, Antoni; Nabavi, Seyed Fazel; Fitzpatrick, Leo R; Nabavi, Seyed Mohammad; Bishayee, Anupam

2017-07-28

The inflammatory process plays a central role in the development and progression of numerous pathological situations, such as inflammatory bowel disease (IBD), autoimmune and neurodegenerative diseases, metabolic syndrome, and cardiovascular disorders. IBDs involve inflammation of the gastrointestinal area and mainly comprise Crohn's disease (CD) and ulcerative colitis (UC). Both pathological situations usually involve recurring or bloody diarrhea, pain, fatigue and weight loss. There is at present no pharmacological cure for CD or UC. However, surgery may be curative for UC patients. The prescribed treatment aims to ameliorate the symptoms and prevent and/or delay new painful episodes. Flavonoid compounds are a large family of hydroxylated polyphenolic molecules abundant in plants, including vegetables and fruits which are the major dietary sources of these compounds for humans, together with wine and tea. Flavonoids are becoming very popular because they have many health-promoting and disease-preventive effects. Most interest has been directed towards the antioxidant activity of flavonoids, evidencing a remarkable free-radical scavenging capacity. However, accumulating evidence suggests that flavonoids have many other biological properties, including anti-inflammatory, antiviral, anticancer, and neuroprotective activities through different mechanisms of action. The present review analyzes the available data about the different types of flavonoids and their potential effectiveness as adjuvant therapy of IBDs.

Effects of dietary flavonoids intake in Saudi patients with coronary heart disease

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Mohammed A Alsaif

2007-01-01

Conclusions: The findings of the study support a potential protective effect of dietary flavonoids in relation to CHD. The study showed that consuming more Flavonoids may have positive effect on lowering blood lipids.

Some methods for blindfolded record linkage

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Christen Peter

2004-06-01

Full Text Available Abstract Background The linkage of records which refer to the same entity in separate data collections is a common requirement in public health and biomedical research. Traditionally, record linkage techniques have required that all the identifying data in which links are sought be revealed to at least one party, often a third party. This necessarily invades personal privacy and requires complete trust in the intentions of that party and their ability to maintain security and confidentiality. Dusserre, Quantin, Bouzelat and colleagues have demonstrated that it is possible to use secure one-way hash transformations to carry out follow-up epidemiological studies without any party having to reveal identifying information about any of the subjects – a technique which we refer to as "blindfolded record linkage". A limitation of their method is that only exact comparisons of values are possible, although phonetic encoding of names and other strings can be used to allow for some types of typographical variation and data errors. Methods A method is described which permits the calculation of a general similarity measure, the n-gram score, without having to reveal the data being compared, albeit at some cost in computation and data communication. This method can be combined with public key cryptography and automatic estimation of linkage model parameters to create an overall system for blindfolded record linkage. Results The system described offers good protection against misdeeds or security failures by any one party, but remains vulnerable to collusion between or simultaneous compromise of two or more parties involved in the linkage operation. In order to reduce the likelihood of this, the use of last-minute allocation of tasks to substitutable servers is proposed. Proof-of-concept computer programmes written in the Python programming language are provided to illustrate the similarity comparison protocol. Conclusion Although the protocols described in

Antioxidant and antidiabetic properties of tartary buckwheat rice flavonoids after in vitro digestion*

Science.gov (United States)

Bao, Tao; Wang, Ye; Li, Yu-ting; Gowd, Vemana; Niu, Xin-he; Yang, Hai-ying; Chen, Li-shui; Chen, Wei; Sun, Chong-de

2016-01-01

Oxidative stress and diabetes have a tendency to alter protein, lipid, and DNA moieties. One of the strategic methods used to reduce diabetes-associated oxidative stress is to inhibit the carbohydrate-digesting enzymes, thereby decreasing gastrointestinal glucose production. Plant-derived natural antioxidant molecules are considered a therapeutic tool in the treatment of oxidative stress and diabetes. The objective of this study was to identify tartary buckwheat rice flavonoids and evaluate the effect of in vitro digestion on their antioxidant and antidiabetic properties. High performance liquid chromatography (HPLC) analysis indicated the presence of rutin as a major component and quercitrin as a minor component of both digested and non-digested flavonoids. Both extracts showed a significant antioxidant capacity, but digested flavonoids showed reduced activity compared to non-digested. There were some decreases of the antioxidant activities (2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picrylhydrazy (DPPH) radical, and ferric reducing antioxidant power (FRAP)) of digested tartary buckwheat rice flavonoids compared with non-digested. Flavonoids from both groups significantly inhibited reactive oxygen species (ROS) production and α-glucosidase activity. Both digested and non-digested flavonoids markedly increased glucose consumption and glycogen content in HepG2 cells. Tartary buckwheat rice flavonoids showed appreciable antioxidant and antidiabetic properties, even after digestion. Tartary buckwheat rice appears to be a promising functional food with potent antioxidant and antidiabetic properties. PMID:27921399

Nature and consequences of non-covalent interactions between flavonoids and macronutrients in foods.

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Bordenave, Nicolas; Hamaker, Bruce R; Ferruzzi, Mario G

2014-01-01

Many of the potential health benefits of flavonoids have been associated with their specific chemical and biological properties including their ability to interact and bind non-covalently to macronutrients in foods. While flavonoid-protein interactions and binding have been the subject of intensive study, significantly less is understood about non-covalent interactions with carbohydrates and lipids. These interactions with macronutrients are likely to impact both the flavonoid properties in foods, such as their radical scavenging activity, and the food or beverage matrix itself, including their taste, texture and other sensorial properties. Overall, non-covalent binding of flavonoids with macronutrients is primarily driven by van der Waals interactions. From the flavonoid perspective, these interactions are modulated by characteristics such as degree of polymerization, molecular flexibility, number of external hydroxyl groups, or number of terminal galloyl groups. From the macronutrient standpoint, electrostatic and ionic interactions are generally predominant with carbohydrates, while hydrophobic interactions are generally predominant with lipids and mainly limited to interactions with flavonols. All of these interactions are involved in flavonoid-protein interactions. While primarily associated with undesirable characteristics in foods and beverages, such as astringency, negative impact on macronutrient digestibility and hazing, more recent efforts have attempted to leverage these interactions to develop controlled delivery systems or strategies to enhance flavonoids bioavailability. This paper aims at reviewing the fundamental bases for non-covalent interactions, their occurrence in food and beverage systems and their impact on the physico-chemical, organoleptic and some nutritional properties of food.

Antioxidant and antidiabetic properties of tartary buckwheat rice flavonoids after in vitro digestion.

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Bao, Tao; Wang, Ye; Li, Yu-Ting; Gowd, Vemana; Niu, Xin-He; Yang, Hai-Ying; Chen, Li-Shui; Chen, Wei; Sun, Chong-de

Oxidative stress and diabetes have a tendency to alter protein, lipid, and DNA moieties. One of the strategic methods used to reduce diabetes-associated oxidative stress is to inhibit the carbohydrate-digesting enzymes, thereby decreasing gastrointestinal glucose production. Plant-derived natural antioxidant molecules are considered a therapeutic tool in the treatment of oxidative stress and diabetes. The objective of this study was to identify tartary buckwheat rice flavonoids and evaluate the effect of in vitro digestion on their antioxidant and antidiabetic properties. High performance liquid chromatography (HPLC) analysis indicated the presence of rutin as a major component and quercitrin as a minor component of both digested and non-digested flavonoids. Both extracts showed a significant antioxidant capacity, but digested flavonoids showed reduced activity compared to non-digested. There were some decreases of the antioxidant activities (2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picrylhydrazy (DPPH) radical, and ferric reducing antioxidant power (FRAP)) of digested tartary buckwheat rice flavonoids compared with non-digested. Flavonoids from both groups significantly inhibited reactive oxygen species (ROS) production and α-glucosidase activity. Both digested and non-digested flavonoids markedly increased glucose consumption and glycogen content in HepG2 cells. Tartary buckwheat rice flavonoids showed appreciable antioxidant and antidiabetic properties, even after digestion. Tartary buckwheat rice appears to be a promising functional food with potent antioxidant and antidiabetic properties.

Interaction of flavonoids, the naturally occurring antioxidants with different media: A UV-visible spectroscopic study

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Naseem, Bushra; Shah, S. W. H.; Hasan, Aurangzeb; Sakhawat Shah, S.

2010-04-01

Quantitative parameters for interaction of flavonoids—the naturally occurring antioxidants, with solvents and surfactants are determined using UV-visible absorption spectroscopy. The availability of flavonoids; kaempferol, apigenin, kaempferide and rhamnetin in micelles of sodium dodecyl sulfate (SDS) is reflected in terms of partition coefficient, Kc. Thermodynamic calculations show that the process of transfer of flavonoid molecules to anionic micelles of SDS is energy efficient. A distortion in flavonoid's morphology occurs in case of kaempferol and apigenin in surfactant and water, exhibited in terms of a new band in the UV region of electronic spectra of these flavonoids. The partition coefficients of structurally related flavonoids are correlated with their antioxidant activities.

Flavonoids as Putative Inducers of the Transcription Factors Nrf2, FoxO, and PPARγ

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Kathrin Pallauf

2017-01-01

Full Text Available 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 PPARγ possibly 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 used α-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 PPARγ response. 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.

Optimization of microwave-assisted extraction of flavonoids from young barley leaves

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Gao, Tian; Zhang, Min; Fang, Zhongxiang; Zhong, Qifeng

2017-01-01

A central composite design combined with response surface methodology was utilized to optimise microwave-assisted extraction of flavonoids from young barley leaves. The results showed that using water as solvent, the optimum conditions of microwave-assisted extraction were extracted twice at 1.27 W g-1 microwave power and liquid-solid ratio 34.02 ml g-1 for 11.12 min. The maximum extraction yield of flavonoids (rutin equivalents) was 80.78±0.52%. Compared with conventional extraction method, the microwave-assisted extraction was more efficient as the extraction time was only 6.18% of conventional extraction, but the extraction yield of flavonoids was increased by 5.47%. The main flavonoid components from the young barley leaf extract were probably 33.36% of isoorientin-7-O-glueoside and 54.17% of isovitexin-7-O-glucoside, based on the HPLC-MS analysis. The barley leaf extract exhibited strong reducing power as well as the DPPH radical scavenging capacity.

Flavonoids as Putative Inducers of the Transcription Factors Nrf2, FoxO, and PPARγ.

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Pallauf, Kathrin; Duckstein, Nils; Hasler, Mario; Klotz, Lars-Oliver; Rimbach, Gerald

2017-01-01

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 PPAR γ possibly 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 used α -tocopherol and ascorbic acid as positive controls. Most of the tested flavonoids, but not the antioxidant vitamins, stimulated Nrf2-, FoxO-, and PPAR γ -dependent promoter activities. Flavonoids activating Nrf2 also tended to induce a FoxO and PPAR γ response. 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.

In Vitro Phytotoxicity and Antioxidant Activity of Selected Flavonoids

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Rita Patrizia Aquino

2012-05-01

Full Text Available The knowledge of flavonoids involved in plant-plant interactions and their mechanisms of action are poor and, moreover, the structural characteristics required for these biological activities are scarcely known. The objective of this work was to study the possible in vitro phytotoxic effects of 27 flavonoids on the germination and early radical growth of Raphanus sativus L. and Lepidium sativum L., with the aim to evaluate the possible structure/activity relationship. Moreover, the antioxidant activity of the same compounds was also evaluated. Generally, in response to various tested flavonoids, germination was only slightly affected, whereas significant differences were observed in the activity of the various tested flavonoids against radical elongation. DPPH test confirms the antioxidant activity of luteolin, quercetin, catechol, morin, and catechin. The biological activity recorded is discussed in relation to the structure of compounds and their capability to interact with cell structures and physiology. No correlation was found between phytotoxic and antioxidant activities.

In silico docking studies of aldose reductase inhibitory activity of commercially available flavonoids

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Arumugam Madeswaran

2012-12-01

Full Text Available The primary objective of this study was to investigate the aldose reductase inhibitory activity of flavonoids using in silico docking studies. In this perspective, flavonoids like biochanin, butein, esculatin, fisetin and herbacetin were selected. Epalrestat, a known aldose reductase inhibitor was used as the standard. In silico docking studies were carried out using AutoDock 4.2, based on the Lamarckian genetic algorithm principle. The results showed that all the selected flavonoids showed binding energy ranging between -9.33 kcal/mol to -7.23 kcal/mol when compared with that of the standard (-8.73 kcal/mol. Inhibition constant (144.13 µM to 4.98 µM and intermolecular energy (-11.42 kcal/mol to -7.83 kcal/mol of the flavonoids also coincide with the binding energy. All the selected flavonoids contributed aldose reductase inhibitory activity because of its structural properties. These molecular docking analyses could lead to the further development of potent aldose reductase inhibitors for the treatment of diabetes.

Flavonoids and coumarins from Hieracium pilosella L. (Asteraceae

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Tadeusz Krzaczek

2011-01-01

Full Text Available Typical chromatographic methods were successfully applied to isolate nine flavonoid compounds and two coumarin glycosides from the inflorescences and the herb of Hieracium pilosella L. Repeated column chromatography, occasionally paper chromatography and recrystallization made the separation of three flavonoid aglycones and six glycosides - possible. Coumarin glycosides were isolated by preparative thin layer chromatography. Subsequent UV, NMR and MS analyses have led to identification of the following flavonoid derivatives: known for the species - apigenin, luteolin, luteolin 7-O- ß-glucopyranoside, luteolin 4’-O-ß-glucopyranoside, isoetin 7-O-ß- -glucopyranoside, isoetin 4’-O-ß-glucuronide and new for the species – kaempferol 3-methyl ether and apigenin 7-O-ß-glucopyranoside. Third isoetin glycoside contained two different sugar moieties: xylose and glucose, probably attached to the hydroxyl groups at C-4’ or C-4’ and C-2’(or 5’ of an aglycone. Umbelliferone 7-O-ß-glucopyranoside (skimmin and new for the genus Hieracium esculetin 7-O-ß-glucopyranoside (cichoriin were determined by NMR and MS methods.

Enhancement of Solubility and Antioxidant Activity of Some Flavonoids Based on the Inclusion Complexation with Sulfobutylether β-Cyclodextrin

International Nuclear Information System (INIS)

Kwon, Yong Eun; Kim, Hyun Myung; Jung, Seun Ho; Park, Se Yeon

2010-01-01

β-CD and SBE-β-CD functioned as a solubilizing agent against three flavonoids. SBE-β-CD is more efficient than native β-CD in solubility enhancement of tested flavonoids. All three tested flavonoids have antioxidant ability. Flavonoid-CD complex positively affected the antioxidant activity comparing with free flavonoids. Throughout this research, SBE-β-CD showed better complexation capacity for the solubility enhancement and bioavailability of tested flavonoids comparing with native β-CD. Flavonoids are polyphenolic photochemicals generally found in plants, foods, and beverages. They contribute to plant colors in fruit, leaves providing a wide spectrum of color from red to blue in flowers. Flavonoids have many good physiological activities such as the antioxidant, antitumor, and antibacterial activities which have been a focus of the attention of many researchers. There are four subgroups of flavonoids, flavone, flavonol, flavanone, and isoflavone, according to their chemical structure

Functions of flavonoids in the central nervous system: Astrocytes as targets for natural compounds.

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Matias, Isadora; Buosi, Andrea Schmidt; Gomes, Flávia Carvalho Alcantara

2016-05-01

In the last decade, there have been major advances in the understanding of the role of glial cells as key elements in the formation, maintenance and refinement of synapses. Recently, the discovery of natural compounds capable of modulating nervous system function has revealed new perspectives on the restoration of the injured brain. Among these compounds, flavonoids stand out as molecules easily obtainable in the diet that have remarkable effects on cognitive performance and behavior. Nevertheless, little is known about the cellular and molecular mechanisms underlying the actions of flavonoids in the nervous system. The present review presents recent advances in the effects of natural compounds, particularly flavonoids, in the nervous system. We shed light on astrocytes as targets of flavonoids and discuss how this interaction might contribute to the effects of flavonoids on neuronal survival, differentiation and function. Finally, we discuss how the effects of flavonoids on astrocytes might contribute to the development of alternative therapeutic approaches to the treatment of neural diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

Optimization of Total Flavonoids Extraction from Coreopsis tinctoria Nutt. by Response Surface Methodology

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Liu, X. F.

2014-11-01

Full Text Available Response surface methodology (RSM was applied to predict optimum conditions for extraction of flavonoid from Coreopsis tinctoria Nutt. A central composite design (CCD was used to monitor the effect of extraction temperature, extraction time, and water-to-material ratio on yield of total flavonoids. The optimal extraction conditions were obtained as water-to-material ratio of 55 ml g−1, extraction temperature of 80 °C and extraction time of 70 minutes. Under these conditions, the average total flavonoids yield, according to the mass of raw material, was 9.0 ± 0.6 %, which corresponds to the predicted value of 8.9 %. Thus, the extraction method was applied successfully to extract total flavonoids from C. tinctoria.

Dietary Antioxidant and Flavonoid Intakes Are Reduced in the Elderly

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Małgorzata Elżbieta Zujko

2015-01-01

Full Text Available The objective of this study was to determine sources and patterns of antioxidant and flavonoid intakes in the elderly (61–74 yrs in comparison with young (20–40 yrs and middle age (41–60 yrs groups in a cross-sectional study. More than 6000 subjects of both genders, aged 20–74 years, participants of the National Multicenter Health Survey (WOBASZ took part in this study. Daily food consumption was estimated by the single 24-hour dietary recall. Dietary total antioxidant capacity (TAC and flavonoid content (FC were calculated according to the amount of food consumed by the participants combined with antioxidant capacity and flavonoid contents in foods. Food consumption, dietary TAC, and FC were significantly lower in the elderly, especially elderly women in comparison to the young and middle age groups. The consumption of tea, coffee, and apples was associated with the largest contribution to dietary TAC and FC in all participants. Despite high nutrient density of the energy-adjusted diet of ageing people, the elderly consumed the lowest amounts of antioxidants and flavonoids due to the lowest food intake.

The antileishmanial activity assessment of unusual flavonoids from Kalanchoe pinnata.

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Muzitano, Michelle F; Tinoco, Luzineide W; Guette, Catherine; Kaiser, Carlos R; Rossi-Bergmann, Bartira; Costa, Sônia S

2006-09-01

The importance of flavonoids for the antileishmanial activity of Kalanchoe pinnata was previously demonstrated by the isolation of quercitrin, a potent antileishmanial flavonoid. In the present study, the aqueous leaf extract from the medicinal plant K. pinnata (Crassulaceae) afforded a kaempferol di-glycoside, named kapinnatoside, identified as kaempferol 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (1). In addition, two unusual flavonol and flavone glycosides already reported, quercetin 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (2) and 4',5-dihydroxy-3',8-dimethoxyflavone 7-O-beta-D-glucopyranoside (3), have been isolated. Their structures were determined via analyses of mono and bi-dimensional (1)H and (13)C NMR spectroscopic experiments and HR-MALDI mass spectra. Because of its restricted occurrence and its abundance in K. pinnata, flavonoid (2) may be a chemical marker for this plant species of high therapeutic potential. The three flavonoids were tested separately against Leishmania amazonenis amastigotes in comparison with quercitrin, quercetin and afzelin. The quercetin aglycone - type structure, as well as a rhamnosyl unit linked at C-3, seem to be important for antileishmanial activity.

Contenido de flavonoides y compuestos fenólicos de mieles chilenas e índice antioxidante Content of flavonoids and phenolic compounds in chilean honeys. Orac index

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Orlando Muñoz

2007-08-01

Full Text Available A comparison of the phenolic content of several Chilean honeys showed great variations in flavonoid concentration among the samples analysed. Higher amounts of phenolics are found in honey from dry climates. The antioxidant effect of extracts, using ORAC analysis, did not correlate with the flavonoid content or with the total phenolic concentration.

Flavonoids and darkness lower PCD in senescing Vitis vinifera suspension cell cultures.

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Bertolini, Alberto; Petrussa, Elisa; Patui, Sonia; Zancani, Marco; Peresson, Carlo; Casolo, Valentino; Vianello, Angelo; Braidot, Enrico

2016-10-26

Senescence is a key developmental process occurring during the life cycle of plants that can be induced also by environmental conditions, such as starvation and/or darkness. During senescence, strict control of genes regulates ordered degradation and dismantling events, the most remarkable of which are genetically programmed cell death (PCD) and, in most cases, an upregulation of flavonoid biosynthesis in the presence of light. Flavonoids are secondary metabolites that play multiple essential roles in development, reproduction and defence of plants, partly due to their well-known antioxidant properties, which could affect also the same cell death machinery. To understand further the effect of endogenously-produced flavonoids and their interplay with different environment (light or dark) conditions, two portions (red and green) of a senescing grapevine callus were used to obtain suspension cell cultures. Red Suspension cell Cultures (RSC) and Green Suspension cell Cultures (GSC) were finally grown under either dark or light conditions for 6 days. Darkness enhanced cell death (mainly necrosis) in suspension cell culture, when compared to those grown under light condition. Furthermore, RSC with high flavonoid content showed a higher viability compared to GSC and were more protected toward PCD, in accordance to their high content in flavonoids, which might quench ROS, thus limiting the relative signalling cascade. Conversely, PCD was mainly occurring in GSC and further increased by light, as it was shown by cytochrome c release and TUNEL assays. Endogenous flavonoids were shown to be good candidates for exploiting an efficient protection against oxidative stress and PCD induction. Light seemed to be an important environmental factor able to induce PCD, especially in GSC, which lacking of flavonoids were not capable of preventing oxidative damage and signalling leading to senescence.

Functional evaluation of synthetic flavonoids and chalcones for potential antiviral and anticancer properties.

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Mateeva, Nelly; Eyunni, Suresh V K; Redda, Kinfe K; Ononuju, Ucheze; Hansberry, Tony D; Aikens, Cecilia; Nag, Anita

2017-06-01

Flavonoids, stilbenes, and chalcones are plant secondary metabolites that often possess diverse biological activities including anti-inflammatory, anti-cancer, and anti-viral activities. The wide range of bioactivities poses a challenge to identify their targets. Here, we studied a set of synthetically generated flavonoids and chalcones to evaluate for their biological activity, and compared similarly substituted flavonoids and chalcones. Substituted chalcones, but not flavonoids, showed inhibition of viral translation without significantly affecting viral replication in cells infected with hepatitis C virus (HCV). We suggest that the chalcones used in this study inhibit mammalian target of rapamycin (mTOR) pathway by ablating phosphorylation of ribosomal protein 6 (rps6), and also the kinase necessary for phosphorylating rps6 in Huh7.5 cells (pS6K1). In addition, selected chalcones showed inhibition of growth in Ishikawa, MCF7, and MDA-MB-231 cells resulting an IC 50 of 1-6µg/mL. When similarly substituted flavonoids were used against the same set of cancer cells, we did not observe any inhibitory effect. Together, we report that chalcones show potential for anti-viral and anti-cancer activities compared to similarly substituted flavonoids. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anti-oxidant and hepatoprotective activities of total flavonoids of Indocalamus latifolius

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Juan Tan

2015-12-01

Full Text Available The total flavonoids of Indocalamus latifolius were evaluated in term of their anti-oxidant and hepatoprotective activities. The results showed that in vitro hepatoprotective and anti-oxidant activities of total flavonoids at doses of 200 and 400 mg/kg and 100 mg/kg, respectively, were comparable to those of the known hepatoprotective drug silymarin at 100 mg/kg. These data were supplemented with histopathological studies of rat liver sections. Seven of the main flavonoid compounds purified by column chromatography using silica gel, sephadex LH-20 and develosil ODS, and determined to be vitexin, orientin, isovitexin, homoorientin, tricin, tricin-7-O-β-D-glucopyranoside and quercetin-3-O-glucopyranoside.

The value of flavonoids for the human nutrition: Short review and perspectives

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Harald P. Hoensch

2015-11-01

Full Text Available Flavonoids are phytochemicals and belong to the polyphenols. A wide variety of beneficial factors has been attributed to their mode of action. Some of their activities concerns the inhibition of inflammatory pathways and the down regulation of genes involved in chronic inflammatory disease states. These genes enhance the inflammatory signaling pathways leading to expression of inflammatory cytokines and chemokines. Flavonoids from fruits, vegetable and tea compounds can block many proinflammatory proteins and thus function as natural inhibitors of inflammation. Instead of using nonsteroidal anti-inflammatory drugs natural inhibitors could possibly be used to suppress the intensity of the inflammation in the chronically inflamed mucosa in patients with chronic inflammatory bowel disease. Natural inhibitors like flavonoids are xenobiotics which are metabolized by the cytochrome P-450 enzymes and conjugating protective enzymes. Flavonoids can induce these protective enzymes by upregulation and thereby could act as protective metabolic barrier within the intestinal mucosa. The nutritional value of flavonoids is probably related to their anti-inflammatory activity and through this mechanism responsible for prevention of neoplasia. The evidence for their clinical efficacy as essential compounds is still preliminary at best and limited but suggestive.

Gamma radiation induced enhancement in the antioxidant and radioprotective activities of flavonoids

International Nuclear Information System (INIS)

Arul Anantha Kumar, A.; Sonwani, Swetha; Bakkiam, D.

2018-01-01

Recently γ-radiation has been used as a tool to induce structural changes in natural biomolecules to enhance their biological and physiological properties. Flavonoids are a family of plant derived polyphenolic compounds having considerable scientific and therapeutic importance. Structurally they are the benzo-γ-pyrone derivatives containing phenolic and pyrane rings. Flavonoid radioprotection is an intense area of research thanks to features like natural origin, effectiveness at non-toxic dose levels and lack of side effects. But till date no report is available on the effect of γ-radiation mediated enhancement in radioprotection activity of flavonoids. In view of this the present study was carried out to determine the γ-radiation induced structural changes in selected flavonoids i.e. apigenin, naringenin and genistein and also to explore the possibility of enhancement in their antioxidant and radioprotective activities

Singlet oxygen reactions with flavonoids. A theoretical-experimental study.

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Morales, Javier; Günther, Germán; Zanocco, Antonio L; Lemp, Else

2012-01-01

Detection of singlet oxygen emission, λ(max) = 1270 nm, following laser excitation and steady-state methods were employed to measure the total reaction rate constant, k(T), and the reactive reaction rate constant, k(r), for the reaction between singlet oxygen and several flavonoids. Values of k(T) determined in deuterated water, ranging from 2.4×10(7) M(-1) s(-1) to 13.4×10(7) M(-1) s(-1), for rutin and morin, respectively, and the values measured for k(r), ranging from 2.8×10(5) M(-1) s(-1) to 65.7×10(5) M(-1) s(-1) for kaempferol and morin, respectively, being epicatechin and catechin chemically unreactive. These results indicate that all the studied flavonoids are good quenchers of singlet oxygen and could be valuable antioxidants in systems under oxidative stress, in particular if a flavonoid-rich diet was previously consumed. Analysis of the dependence of rate constant values with molecular structure in terms of global descriptors and condensed Fukui functions, resulting from electronic structure calculations, supports the formation of a charge transfer exciplex in all studied reactions. The fraction of exciplex giving reaction products evolves through a hydroperoxide and/or an endoperoxide intermediate produced by singlet oxygen attack on the double bond of the ring C of the flavonoid.

Flavonoid biosynthesis controls fiber color in naturally colored cotton

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Hai-Feng Liu

2018-04-01

Full Text Available The existence of only natural brown and green cotton fibers (BCF and GCF, respectively, as well as poor fiber quality, limits the use of naturally colored cotton (Gossypium hirsutum L.. A better understanding of fiber pigment regulation is needed to surmount these obstacles. In this work, transcriptome analysis and quantitative reverse transcription PCR revealed that 13 and 9 phenylpropanoid (metabolic pathway genes were enriched during pigment synthesis, while the differential expression of phenylpropanoid (metabolic and flavonoid metabolic pathway genes occurred among BCF, GCF, and white cotton fibers (WCF. Silencing the chalcone flavanone isomerase gene in a BCF line resulted in three fiber phenotypes among offspring of the RNAi lines: BCF, almost WCF, and GCF. The lines with almost WCF suppressed chalcone flavanone isomerase, while the lines with GCF highly expressed the glucosyl transferase (3GT gene. Overexpression of the Gh3GT or Arabidopsis thaliana 3GT gene in BCF lines resulted in GCF. Additionally, the phenylpropanoid and flavonoid metabolites of BCF and GCF were significantly higher than those of WCF as assessed by a metabolomics analysis. Thus, the flavonoid biosynthetic pathway controls both brown and green pigmentation processes. Like natural colored fibers, the transgenic colored fibers were weaker and shorter than WCF. This study shows the potential of flavonoid pathway modifications to alter cotton fibers’ color and quality.

Singlet oxygen reactions with flavonoids. A theoretical-experimental study.

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Javier Morales

Full Text Available Detection of singlet oxygen emission, λ(max = 1270 nm, following laser excitation and steady-state methods were employed to measure the total reaction rate constant, k(T, and the reactive reaction rate constant, k(r, for the reaction between singlet oxygen and several flavonoids. Values of k(T determined in deuterated water, ranging from 2.4×10(7 M(-1 s(-1 to 13.4×10(7 M(-1 s(-1, for rutin and morin, respectively, and the values measured for k(r, ranging from 2.8×10(5 M(-1 s(-1 to 65.7×10(5 M(-1 s(-1 for kaempferol and morin, respectively, being epicatechin and catechin chemically unreactive. These results indicate that all the studied flavonoids are good quenchers of singlet oxygen and could be valuable antioxidants in systems under oxidative stress, in particular if a flavonoid-rich diet was previously consumed. Analysis of the dependence of rate constant values with molecular structure in terms of global descriptors and condensed Fukui functions, resulting from electronic structure calculations, supports the formation of a charge transfer exciplex in all studied reactions. The fraction of exciplex giving reaction products evolves through a hydroperoxide and/or an endoperoxide intermediate produced by singlet oxygen attack on the double bond of the ring C of the flavonoid.

Qualitative and quantitative analysis of flavonoids of the strawberry tree - Arbutus unedo L. (Ericaceae).

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Males, Zeljan; Plazibat, Misko; Vundać, Vjera Bilusić; Zuntar, Irena

2006-06-01

The leaves and fruits of strawberry tree - Arbutus unedo L., collected from two separate geographic locations in Croatia were investigated to determine their flavonoid composition and content. Quercitrin, isoquercitrin, hyperoside and rutin were identified in all leaf samples by means of thin-layer chromatography; the fruits contained only isoquercitrin. Chlorogenic acid was present in some leaf samples. The content of flavonoids depended on the plant organ investigated, date of collection and the locality. Spectrophotometric determination of the flavonoids indicated that the leaves are richer in flavonoids (0.52-2.00%) than fruits (0.10-0.29%).

Optimization of conditions for supercritical fluid extraction of flavonoids from hops (Humulus lupulus L.)*

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He, Guo-qing; Xiong, Hao-ping; Chen, Qi-he; Ruan, Hui; Wang, Zhao-yue; Traoré, Lonseny

2005-01-01

Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO2 extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at 50 °C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield flavonoids (7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid in hops. PMID:16187413

Habitual intake of dietary flavonoids and risk of Parkinson disease.

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Gao, X; Cassidy, A; Schwarzschild, M A; Rimm, E B; Ascherio, A

2012-04-10

To prospectively examine whether higher intakes of total flavonoids and their subclasses (flavanones, anthocyanins, flavan-3-ols, flavonols, flavones, and polymers) were associated with a lower risk of developing Parkinson disease (PD). In the current analysis, we included 49,281 men in the Health Professional Follow-up Study and 80,336 women from the Nurses' Health Study. Five major sources of flavonoid-rich foods (tea, berry fruits, apples, red wine, and orange/orange juice) were also examined. Flavonoid intake was assessed using an updated food composition database and a validated food frequency questionnaire. We identified 805 participants (438 men and 367 women) who developed PD during 20-22 years of follow-up. In men, after adjusting for multiple confounders, participants in the highest quintile of total flavonoids had a 40%lower PD risk than those in the lowest quintile (hazard ratio [HR] = 0.60; 95% confidence interval 0.43, 0.83; p trend = 0.001). No significant relationship was observed in women (p trend = 0.62) or in pooled analyses (p trend = 0.23). In the pooled analyses for the subclasses, intakes of anthocyanins and a rich dietary source, berries, were significantly associated with a lower PD risk (HR comparing 2 extreme intake quintiles were 0.76 for anthocyanins and 0.77 for berries, respectively; p trend < 0.02 for both). Our findings suggest that intake of some flavonoids may reduce PD risk, particularly in men, but a protective effect of other constituents of plant foods cannot be excluded.

Development, validation and reproducibility of a food frequency questionnaire to measure flavonoid intake in older Australian adults.

Science.gov (United States)

Kent, Katherine; Charlton, Karen E

2018-02-01

To develop and assess the validity and reproducibility of a food frequency questionnaire (FFQ) to measure total flavonoid intake, and individual flavonoid subclasses, in older adults. Retrospective analysis of flavonoid intake in older adults informed the development of a FFQ to measure flavonoid intake and determine the flavonoid subclasses consumed (anthocyanins, flavan-3-ols, flavones, flavonols and flavanones). Older adults (n = 42, mean age 75.3 ± 8.6 years) attended two interviews 1 month apart where anthropometrics (height and weight), blood pressure (BP), demographic data and a 93-item self-administered FFQ were collected. A 4-day food record (FR) was randomly administered between the two interview dates, and each food item was assigned a flavonoid and flavonoid subclass content using the United States Department of Agriculture flavonoid database. The criterion validity and reproducibility of the FFQ was assessed against a 4-day FR using the Wilcoxon signed-rank sum test, Spearman's correlation coefficient (r), Bland-Altman Plots and Cohen's kappa. Total flavonoid intake was determined (median intake FFQ = 919.3 mg/day, FR = 781.4 mg/day). Tests of validity indicated that the FFQ consistently overestimated total flavonoid intake compared with the 4-day FR. There was a significant difference in estimates between the FFQ and the 4-day FR for total flavonoid intake (Wilcoxon signed-rank sum P tests of validity indicated greater discrepancy compared with 4-day FR. The FFQ showed high reproducibility for estimating total flavonoid intake (FFQ1vsFFQ2: Wilcoxon signed-rank sum test, P > 0.05; Spearman's r 0.91, P tests of reproducibility between FFQ1 and FFQ2 showed similarly high reproducibility. The developed FFQ appears suitable for satisfactorily ranking individuals according to total flavonoid intake. The FFQ shows limitations for estimating absolute total flavonoid intake and intake of flavonoid subclasses in comparison to a 4-day FR in terms of

Fate in Soil of Flavonoids Released from White Clover (Trifolium repens L.)

DEFF Research Database (Denmark)

Carlsen, Sandra C. K.; Pedersen, Hans A.; Spliid, Niels H.

2012-01-01

the presence in soil of bioactive secondary metabolites from clover has received limited attention. In this paper we examine for the first time the release of flavonoids both from field-grown white clover and from soil-incorporated white clover plants of flavonoids, as analyzed by LC-MS/MS. The dominant...... flavonoid aglycones were formononetin, medicarpin, and kaempferol. Soil-incorporated white clover plants generated high concentrations of the glycosides kaempferol-Rha-Xyl-Gal and quercetin-Xyl-Gal. Substantial amounts of kaempferol persisted in the soil for days while the other compounds were degraded...

Quantitative study of flavonoids in leaves of citrus plants.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M; Koizumi, M; Ito, C; Furukawa, H

2000-09-01

Leaf flavonoids were quantitatively determined in 68 representative or economically important Citrus species, cultivars, and near-Citrus relatives. Contents of 23 flavonoids including 6 polymethoxylated flavones were analyzed by means of reversed phase HPLC analysis. Principal component analysis revealed that the 7 associations according to Tanaka's classification were observed, but some do overlap each other. Group VII species could be divided into two different subgroups, namely, the first-10-species class and the last-19-species class according to Tanaka's classification numbers.

Metabolic engineering of flavonoids in tomato (Solanum lycopersicum): the potential for metabolomics

NARCIS (Netherlands)

Bovy, A.G.; Schijlen, E.G.W.M.; Hall, R.D.

2007-01-01

Flavonoids comprise a large and diverse group of polyphenolic plant secondary metabolites. In plants, flavonoids play important roles in many biological processes such as pigmentation of flowers, fruits and vegetables, plant-pathogen interactions, fertility and protection against UV light. Being

DETERMINATION OF FLAVONOIDS OF WILLOW TRIANDRA (SALIX TRIANDRA L., GROWING IN THE NORTH CAUCASUS

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E. G. Sannikova

2016-01-01

Full Text Available Plants of willow genus are rich in various flavonoids. In 60-e years of the XX century the works of V. A. Kompantsev showed that leaves of willow triandra, growing in the North Caucasus, contain up to 5% of rutin. The method, which required long sample preparation (extraction of the raw material with TLC, chromatographic layer extraction with methanol, removal of the solvent, dissolution in ethanol, optical density measurements was used. Currently available and simple methods for the determination of rutin in plant material are described. Given that leaves of Salix triandra contain significant amounts of rutin and can be a potential raw material for the creation of medicines on their basis, it is essential to determine the amount of flavonoids in the leaves of Salix triandra and its branches.The purpose of this study is determination of the amount of flavonoids in the willow triandra, growing in the North Caucasus, depending on the place and time of collection.Methods. TLC and the method of differential spectrophotometry were used to study chemical reactions. Results. The presence of flavonoids in various vegetative plant organs was established using qualitative reactions (cyanidin test; boric-citric reaction; the reaction with solution of lead acetate and solution of ammonia. Rutin and quercetin flavonoids in the presence of standard samples were identified using TLC. the method of differential spectrophotometry, based on the reaction of flavonoids with aluminum chloride was used for the quantitative determination of the amount of flavonoids. It is shown that the greatest quantity of flavonoids amount accumulated in the leaves (up to 3.76%, its value in branches is slightly smaller (up to 3.26%. The branches without leaves have almost 10 times less flavonoids. It was established experimentally that the accumulation of flavonoids in raw material of Salix triandra is dependent on the place and time of

Oroxylum indicum Seeds—Analysis of Flavonoids by Micellar Electrokinetic Chromatography

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Anja Krüger

2013-02-01

Full Text Available Flavonoids are bioactive constituents in Oroxylum indicum seeds, an Asian traditional remedy used for the treatment of respiratory infections. In this study the first capillary electrophoretic method for their determination is presented. By using a 25 mM borax buffer at pH 9.2 containing 10 mM SDS as detergent, the determination of seven flavonoids was feasible in only 13 min. Method validation confirmed that the assay is in accordance with ICH requirements in respect to linearity, selectivity, sensitivity, accuracy and precision. Quantitative results revealed that baicalein-7-O-gentiobioside is the most abundant flavonoid in the drug (1.19 to 5.33%, followed by other baicalein derivatives (7-O-glucoside, 7-O-glucuronide. These observations were in good qualitative and quantitative agreement with LC-MS results.

Determination of Flavonoids in Wine by High Performance Liquid Chromatography

Science.gov (United States)

da Queija, Celeste; Queirós, M. A.; Rodrigues, Ligia M.

2001-02-01

The experiment presented is an application of HPLC to the analysis of flavonoids in wines, designed for students of instrumental methods. It is done in two successive 4-hour laboratory sessions. While the hydrolysis of the wines is in progress, the students prepare the calibration curves with standard solutions of flavonoids and calculate the regression lines and correlation coefficients. During the second session they analyze the hydrolyzed wine samples and calculate the concentrations of the flavonoids using the calibration curves obtained earlier. This laboratory work is very attractive to students because they deal with a common daily product whose components are reported to have preventive and therapeutic effects. Furthermore, students can execute preparative work and apply a more elaborate technique that is nowadays an indispensable tool in instrumental analysis.

Antioxidant activity of banana flavonoids.

Science.gov (United States)

Vijayakumar, S; Presannakumar, G; Vijayalakshmi, N R

2008-06-01

The antioxidant activity of flavonoids from banana (Musa paradisiaca) was studied in rats fed normal as well as high fat diets. Concentrations of peroxidation products namely malondialdehyde, hydroperoxides and conjugated diens were significantly decreased whereas the activities of catalase and superoxide dismutase were enhanced significantly. Concentrations of glutathione were also elevated in the treated animals.

Flavonoid Profile of Saskatoon Berries (Amelanchier alnifolia Nutt. and Their Health Promoting Effects

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Jiri Mlcek

2013-10-01

Full Text Available Flavonoids are a significant group of secondary metabolites in plants. Many of these compounds are potent antioxidants, being an important part in food products derived from the plants. The current status of research on flavonoid compounds in the fruit of Saskatoon berries (Amelanchier alnifolia Nutt. and their health promoting effects, including recommended utilization, are reviewed. The major classes of flavonoids in the fruit are flavonols (quercetin and rutin, flavanes (proanthocyanidin compounds ranging from dimers through to heptamers and even higher polymers and finally anthocyanins. The flavonoids represented the group of polyphenols that mostly contributed to the antioxidant activity of Saskatoon berries. High content of the flavoinoids antioxidants in the fruit is responsible for the observed anti-inflammatory, antidiadiabetic and chemo-protective effects.

Leishmanicidal Activity of Nine Novel Flavonoids from Delphinium staphisagria

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Inmaculada Ramírez-Macías

2012-01-01

Full Text Available Objectives. To evaluate the in vitro leishmanicidal activity of nine flavonoid derivatives from Delphinium staphisagria against L. infantum and L. braziliensis. Design and Methods. The in vitro activity of compounds 1–9 was assayed on extracellular promastigote and axenic amastigote forms and on intracellular amastigote forms of the parasites. Infectivity and cytotoxicity tests were carried on J774.2 macrophage cells using Glucantime as the reference drug. The mechanisms of action were analysed performing metabolite excretion and transmission electronic microscope ultrastructural alteration studies. Results. Nine flavonoids showed leishmanicidal activity against promastigote as well as amastigote forms of Leishmania infantum and L. braziliensis. These compounds were nontoxic to mammalian cells and were effective at similar concentrations up to or lower than that of the reference drug (Glucantime. The results showed that 2″-acetylpetiolaroside (compound 8 was clearly the most active. Conclusion. This study has demonstrated that flavonoid derivatives are active against L. infantum and L. braziliensis.

The influence of phase II conjugation on the biological activity of flavonoids

NARCIS (Netherlands)

Beekmann, K.

2016-01-01

Flavonoid consumption is often correlated with a wide range of health effects, such as the prevention of cardiovascular diseases, neurodegenerative diseases, and diabetes. These effects are usually ascribed to the activity of the parent flavonoid aglycones, even though these forms of the

A study on the antitumour effect of total flavonoids from Pteris ...

African Journals Online (AJOL)

The objective of this paper was to investigate the inhibitory effect of total flavonoids from Pteris multifida Poir on growth of transplanted H22 tumour in mice. H22 tumour-bearing mice model was established; the experimental animals were divide/d into the model group, Pteris multifida Poir total flavonoids high-, low-dose ...

Differential flavonoid response to enhanced UV-B radiation in Brassica napus

International Nuclear Information System (INIS)

Olsson, L.C.; Veit, M.; Weissenböck, G.; Bornman, J.F.

1998-01-01

We have examined the qualitative and quantitative differences in methanol-soluble flavonoids of leaves of two cultivars of Brassica napus, which were grown with or without (control) supplemental UV-B radiation. The flavonoids were identified using HPLC-diode array spectroscopy (-DAS), -electrospray ionization-mass spectroscopy (-ESI-MS) and 1H and 13C NMR, and quantitatively analysed by HPLC-DAS. After exposure to supplementary UV-B radiation, the overall amount of soluble flavonoids, kaempferol and quercetin glycosides, increased by ca 150% in cv. Paroll, compared to control plants. Cultivar Stallion showed a 70% increase, and also a lower overall content of soluble flavonoids compared to Paroll. The supplementary UV-B radiation resulted in a marked, specific increase in the amount of quercetin glycosides relative to the kaempferol glycosides with a 36- and 23-fold increase in cvs Paroll and Stallion, respectively. Four of the flavonol glycosides appearing after supplemental UV-B exposure were identified as quercetin- and kaempferol 3-sophoroside-7-glucoside and 3-(2″′-E-sinapoylsophoroside)-7-glucoside. (author)

Sonochemical Effects on 14 Flavonoids Common in Citrus: Relation to Stability

Science.gov (United States)

Qiao, Liping; Sun, Yujing; Chen, Rongrong; Fu, Yu; Zhang, Wenjuan; Li, Xin; Chen, Jianchu; Shen, Yan; Ye, Xingqian

2014-01-01

The sonochemical effects of ultrasound (US) treatment on 14 flavonoids representing the main flavonoids in citrus fruit were investigated in a standard mixture by stability evaluation of a model system. Degradation products were further tentatively identified by Fourier transform infrared spectroscopy and high-performance liquid chromatography–ultraviolet detection–electrospray ionization tandem mass spectrometry. Thirteen flavonoids (i.e., eriocitrin, narirutin, neohesperidin, quercitrin, eridictyol, didymin, naringenin, luteolin, sinensetin, nobiletin, tangeretin, naringin, and hesperidin) were fairly stable whereas quercetin was degraded significantly by US treatment. The types of solvent and temperature used were important factors that determined the resulting degradation reactions. The degradation rate of quercetin was highest in 80% ethanol aqueous solution and decreased with increasing temperature. Longer US durations caused increases in the extent of quercetin degradation. Liquid height, ultrasonic intensity, pulse length, and duty cycle of US affected degradation rates but did not change the nature of degradation of the flavonoids. Four types of reactions occurred simultaneously for quercetin under US treatment: oxidation, addition, polymerization, and decomposition. Eight degradation products were tentatively identified as dimer, alcohol addition, oxidation, and decomposition products. PMID:24516562

Phthalate exposure, flavonoid consumption and breast cancer risk among Mexican women.

Science.gov (United States)

Mérida-Ortega, Ángel; Hernández-Alcaraz, César; Hernández-Ramírez, Raúl U; García-Martínez, Angélica; Trejo-Valdivia, Belem; Salinas-Rodríguez, Aarón; Svensson, Katherine; Cebrián, Mariano E; Franco-Marina, Francisco; López-Carrillo, Lizbeth

2016-11-01

To evaluate if selected phthalate exposure and flavonoid intake interact on breast cancer (BC) risk. Interviews and urine samples were obtained from 233 women with histologically confirmed BC and 221 healthy controls matched by age and place of residence, from various states of northern Mexico. Urinary metabolites concentrations of diethyl phthalate (DEP), butyl benzyl phthalate (BBzP) and dioctyl phthalate (DOP) were determined by solid-phase extraction coupled with high-performance liquid chromatography/isotope dilution/tandem mass spectrometry. Using a semiquantitative food frequency questionnaire, consumption of five types of flavonoids (anthocyanidins, flavan-3-ols, flavanones, flavones and flavonols) was estimated according to three food groups: vegetables, fruits and legumes-oil seeds. A higher intake of anthocyanidins and flavan-3-ols (from vegetables), synergistically increased the negative association between BBzP and BC. No other significant flavonoid-phthalate multiplicative interactions on the risk for BC were found. The consumption of some flavonoids may interact with exposure to phthalates on the risk of BC. Epidemiological and underlying mechanisms information is still insufficient and requires further investigations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radical scavenging behavior of eriodictyol and fustin flavonoid compounds - A DFT study

Science.gov (United States)

Sadasivam, K.; Praveena, R.; Anbakzhakan, K.

2018-05-01

The density functional theory (DFT) protocol together with B3LYP/6-311G(d,p) level of theory has been utilized to explore and compare the structural features and molecular characteristics of two naturally occurring flavonoid compounds eriodictyol and fustin. The -OH bond dissociation energy (BDE) for all the radical species have been computed and interpreted in accordance with the radical scavenging activity. The ionization potential (IP) value of fustin flavonoid compound was found to be within the range of synthetic food additives. The polar nature and their capacity to polarise other atoms are established through the dipole moment analysis. Additionally, various parameters that are relevant to chemical potential such as electron affinity, hardness, softness, electro negativity and electrophilic index were calculated and analysed in the light of quercetin flavonoid compound in view of their antioxidant activity. The antioxidant capability of fustin is found to be superior to eriodictyol flavonoid.

Effect of dry salting on flavonoid profile and antioxidant capacity of Algerian olive cultivars

International Nuclear Information System (INIS)

Soufi, O.; Romero, C.; Motilva, M.J.; Borras Gaya, X.; Louaileche, H.

2016-01-01

This study investigated the changes in the flavonoid profile and antioxidant capacity of five olive cultivars after dry salting. The antioxidant activity was determined using ferric reducing ability power (FRAP), oxygen radical absorbance capacity (ORAC), and β-carotene bleaching assays. The results showed that the effects of dry salting on the analyzed parameters were significant (P<0.05). It caused a decrease in total flavonoids with a loss rate of 55%. The HPLC analysis of extracts revealed the presence of four flavonoids: rutin, luteolin-7-glucoside, cyanidin-3-glucoside and cyanidin-3-rutinoside. Among the studied cultivars, Azeradj was characterized by high levels of flavonoids. Concerning the antioxidant activity, diverging results were obtained using different antioxidant assays. Overall, the dry salting induced a reduction in the antioxidant activity with variable values depending on the cultivar. Among the used methods, high correlations were found between flavonoid contents and the FRAP assay. (Author)

Effect of dry salting on flavonoid profile and antioxidant capacity of Algerian olive cultivars

Energy Technology Data Exchange (ETDEWEB)

Soufi, O.; Romero, C.; Motilva, M.J.; Borras Gaya, X.; Louaileche, H.

2016-07-01

This study investigated the changes in the flavonoid profile and antioxidant capacity of five olive cultivars after dry salting. The antioxidant activity was determined using ferric reducing ability power (FRAP), oxygen radical absorbance capacity (ORAC), and β-carotene bleaching assays. The results showed that the effects of dry salting on the analyzed parameters were significant (P<0.05). It caused a decrease in total flavonoids with a loss rate of 55%. The HPLC analysis of extracts revealed the presence of four flavonoids: rutin, luteolin-7-glucoside, cyanidin-3-glucoside and cyanidin-3-rutinoside. Among the studied cultivars, Azeradj was characterized by high levels of flavonoids. Concerning the antioxidant activity, diverging results were obtained using different antioxidant assays. Overall, the dry salting induced a reduction in the antioxidant activity with variable values depending on the cultivar. Among the used methods, high correlations were found between flavonoid contents and the FRAP assay. (Author)

Linkage Behavior and Practices of Agencies in the Agricultural ...

African Journals Online (AJOL)

The study examined the linkage behaviour and practices of agencies in the ... institutes; while (61.5%,65.5%and 50.0%) indicated that linkages with universities of ... Existing institutional framework for linkages between research and extension ...

FLAVONOIDS QUANTITATIVE DETERMINATION IN THE INFLORESCENCES OF TAGETES ERECTA AND TAGETES PATULA

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Е. A. Malyugina

2013-12-01

Full Text Available INTRODUCTION The Genus marigold (Tagetes belongs to the family Asteraceae. The native land of this genus is the Central America. The genus marigold contains about 56 species and more than 600 forms and cultivars that are widely distributed around the world. The most distributed species are T. erecta L. and T. patula L. The chemical constituents of marigolds and their biological activity are intensively studied now. These plants contain more than 100 secondary metabolites, e.g. flavonoids, carotenoids, steroids, alkaloids, phenol derivate and others. The biological active carotenoids, flavonoids, essential oil, vitamins that contained in the inflorescences and herbs of Tagetes L. has anti-oxidant, anti-inflammatory, antibacterial and other activity. Tagetes L. genus plants widely used in traditional medicine as wound healing, hepatoprotective, choleretic, and adaptogenic medicines. The essential oil of marigolds has insecticidal properties and used in national economics. Also this plants are used in ophthalmology. The main biological active compounds of Tagetes L. are flavonoids. Composition of the most perspective carotenoid-contain species and cultivars of Tagetes L., such as T. patula nana L. (Gold Kopfen, Orangeflamme and T. erecta L. remains poorly understood. They need to be studied as perspective source of the biological active flavonoids. OBJECTIVE The aim of the study was to determine flavonoids contain in the inflorescences of Tagetes erecta L. cultivars “Equinox” and “Hawaii” and Tagetes patula L. cultivars “Gold Kopfen” and “Orangeflamme”. To determine the most perspective cultivars for obtaining the medicines. MATERIALS AND METHODS Tagetes patula L. and Tagetes erecta L. was selected in the present study. Plant material (inflorescences was collected from different regions of Ukraine. About 0.1 of crushed inflorescences was extracted by ethanol about 30 minutes twice, filtered and cooled. Appropriate quantities of

Phytochemical screening and quantification of flavonoids from leaf extract of Jatropha curcas Linn.

Science.gov (United States)

Ebuehi, O A T; Okorie, N A

2009-01-01

The Jatropha curcas L. (Euphorbiaceae) herb is found in SouthWest, Nigeria and other parts of West Africa, and is claimed to possess anti-hypertensive property. The phytochemical screening and flavonoid quantification of the leaf extract of Jatropha curcas Linn were studied. The phytochemical screening of the methanolic leaf extract of J. curcas L. was carried using acceptable and standard methods. The flavonoid contents of the leaf extract of Jatropha curcas L. were determined using thin layer chromatography (TLC), infrared spectroscopy (IRS) and a reversed phase high performance liquid chromatography (HPLC). The phytochemical screening of the methanolic extract of the leaves of the plant shows the presence of alkaloids, cardiac glycosides, cyanogenic glycosides, phlobatannins, tannins, flavonoids and saponins. To quantify the flavonoid contents of leaf extract of Jatropha curcas L, extracts from the plant samples where examined in a C-18 column with UV detection and isocratic elution with acetonitrile; water (45:55). Levels of flavonoids (flavones) in leaves ranged from 6:90 to 8:85 mg/g dry weight. Results indicate that the methanolic extract of the leaves of Jatropha curcas L. contains useful active ingredients which may serve as potential drug for the treatment of diseases. In addition, a combination of TLC, IRS and HPLC can be used to analyse and quantify the flavonoids present in the leaves of Jatropha curcas L.

Protective effect of mulberry flavonoids on sciatic nerve in alloxan-induced diabetic rats

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Ma Song-Tao

2014-12-01

Full Text Available Mulberry leaves (Morus alba L. are a traditional Chinese medicine for blood serum glucose reduction. This study evaluated the protective effects of mulberry flavonoids on sciatic nerve in alloxan-induced diabetic rats. In this study, 80 Sprague-Dawley rats were divided into five groups: A (control, B (diabetic treated with saline, C-D (diabetic treated with 0.3, 0.1 g/kg mulberry flavonoids once a day for 8 weeks and E (diabetic treated with 0.3 mg/kg methycobal. The diabetic condition was induced by intraperitoneal injection of 200 mg/kg alloxan dissolved in saline. At the end of the experimental period, blood, and tissue samples were obtained for biochemical and histopathological investigation. Treatment with 0.3 g/kg mulberry flavonoids significantly inhibited the elevated serum glucose (P< 0.01. The increased myelin sheath area (P< 0.01, myelinated fiber cross-sectional area and extramedullary fiber number (P< 0.05 were also reduced in alloxan-induced rats treated with 0.3 g/kg mulberry flavonoids. 0.3 g/kg mulberry flavonoids also markedly decreased onion-bulb type myelin destruction and degenerative changes of mitochondria and Schwann cells. These findings demonstrate that mulberry flavonoids may improve the recovery of a severe peripheral nerve injury in alloxan-induced diabetic rats and is likely to be useful as a potential treatment on peripheral neuropathy (PN in diabetic rats.

Correlation of binding efficacies of DNA to flavonoids and their induced cellular damage.

Science.gov (United States)

Das, Asmita; Majumder, Debashis; Saha, Chabita

2017-05-01

Flavonoids are dietary intakes which are bestowed with several health benefits. The most studied property of flavonoids is their antioxidant efficacy. Among the chosen flavonoids Quercetin, Kaempferol and Myricetin is catagorized as flavonols whereas Apigenin and Luteolin belong to the flavone group. In the present study anti-cancer properties of flavonoids are investigated on the basis of their binding efficacy to ct-DNA and their ability to induce cytotoxicity in K562 leukaemic cells. The binding affinities of the flavonoids with calf thymus DNA (ct-DNA) are in the order Quercetin>Myricetin>Luteolin>Kaempferol>Apigenin. Quercetin with fewer OH than myricetin has higher affinity towards DNA suggesting that the number and position of OH influence the binding efficacies of flavonoids to ct-DNA. CD spectra and EtBr displacement studies evidence myricetin and apigenin to be stronger intercalators of DNA compared to quercetin. From comet assay results it is observed that quercetin and myricetin when used in combination induce higher DNA damage in K562 leukemic cells than when tested individually. Higher binding efficacy has been recorded for quercetin to DNA at lower pH, which is the micro environment of cancerous cells, and hence quercetin can act as a potential anti-cancer agent. Presence of Cu also increases cellular damage as recorded by comet assay. Copyright © 2017. Published by Elsevier B.V.

Pharmacokinetic Study of Bioactive Flavonoids in the Traditional Japanese Medicine Keigairengyoto Exerting Antibacterial Effects against Staphylococcus aureus

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Takashi Matsumoto

2018-01-01

Full Text Available Recent studies have demonstrated that flavonoid glucuronides can be deconjugated to the active form aglycone by β-glucuronidase-expressing macrophages. Keigairengyoto (KRT is a flavonoid-rich traditional Japanese medicine reported to enhance bacterial clearance through immune modulation. Our aims are to examine the pharmacokinetics of KRT flavonoids and to identify active flavonoids contributing to the adjuvant effects of KRT. KRT was evaluated at pharmacokinetic analysis to quantify absorbed flavonoids, and cutaneous infection assay induced in mice by inoculation of Staphylococcus aureus. Preventive or therapeutic KRT administration reduced the number of bacteria in the infection site as well as macroscopic and microscopic lesion scores with efficacies similar to antibiotics. Pharmacokinetic study revealed low plasma levels of flavonoid aglycones after KRT administration; however, plasma concentrations were enhanced markedly by β-glucuronidase treatment, with baicalein the most abundant (Cmax, 1.32 µg/mL. In random screening assays, flavonoids such as bacalein, genistein, and apigenin enhanced bacteria phagocytosis by macrophages. Glucuronide bacalin was converted to aglycone baicalein by incubation with living macrophages, macrophage lysate, or skin homogenate. Taken together, the adjuvant effect of KRT may be due to some blood-absorbed flavonoids which enhance macrophage functions in host defense. Flavonoid-rich KRT may be a beneficial treatment for infectious skin inflammation.

Exploitation of linkage learning in evolutionary algorithms

CERN Document Server

Chen, Ying-ping

2010-01-01

The exploitation of linkage learning is enhancing the performance of evolutionary algorithms. This monograph examines recent progress in linkage learning, with a series of focused technical chapters that cover developments and trends in the field.

ANALYSIS OF INTER SECTORAL LINKAGES IN SEMARANG REGENCY

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Fafurida

2014-03-01

Full Text Available This research aims to analyze inter economic sectoral linkages and to arrange the Klassen typology of economic sectors in Semarang Regency. The Klassen typology is composed from the result of the linkage analysis. To construct the analysis, this paper also utulizes the input-output analysis. It finds that service sector has the highest backward linkage while farming sector has the highest forward linkage. Based on the Klassen typology analysis, sectors with the highest backward and forward linkages and potential to be the leading sector are farming sector, dan trade, hotel and restaurant sector.Keywords: Backward linkage,forward linkage, Klassen typologyJEL classification number: R15, O21AbstrakPenelitian ini bertujuan untuk mengkaji seberapa besar keterkaitan antar sektor ekonomi di Kabupaten Semarang dan memetakan tipologi Klassennya. Tipologi Klasen disusun berdasarkan hasil perhitungan analisis keterkaitannya. Untuk menyusun analisis tersebut, paper ini juga menggunakan analisis input-output. Hasil penelitian menunjukkan bahwa sektor jasa memiliki keterkaitan ke belakang tertinggi dibandingkan dengan sektor lainnya. Sementara itu, sektor pertanian merupakan sektor yang memiliki keterkaitan ke depan tertinggi. Berdasarkan hasil analisis tipologi Klassen, sektor yang memiliki keterkaitan ke depan dan ke belakang yang tinggi dan dapat menjadi sektor unggulan adalah sektor perdagangan, hotel dan sektor restoran.Kata kunci: Keterkaitan ke belakang, keterkaitan ke depan, tipologi KlassenJEL classification numbers: R15, O21

Posterior probability of linkage and maximal lod score.

Science.gov (United States)

Génin, E; Martinez, M; Clerget-Darpoux, F

1995-01-01

To detect linkage between a trait and a marker, Morton (1955) proposed to calculate the lod score z(theta 1) at a given value theta 1 of the recombination fraction. If z(theta 1) reaches +3 then linkage is concluded. However, in practice, lod scores are calculated for different values of the recombination fraction between 0 and 0.5 and the test is based on the maximum value of the lod score Zmax. The impact of this deviation of the test on the probability that in fact linkage does not exist, when linkage was concluded, is documented here. This posterior probability of no linkage can be derived by using Bayes' theorem. It is less than 5% when the lod score at a predetermined theta 1 is used for the test. But, for a Zmax of +3, we showed that it can reach 16.4%. Thus, considering a composite alternative hypothesis instead of a single one decreases the reliability of the test. The reliability decreases rapidly when Zmax is less than +3. Given a Zmax of +2.5, there is a 33% chance that linkage does not exist. Moreover, the posterior probability depends not only on the value of Zmax but also jointly on the family structures and on the genetic model. For a given Zmax, the chance that linkage exists may then vary.

Flavonoids can protect maize DNA from the induction of ultraviolet radiation damage

International Nuclear Information System (INIS)

Stapleton, A.E.; Walbot, V.

1994-01-01

Diverse flavonoid compounds are widely distributed in angiosperm families. Flavonoids absorb radiation in the ultraviolet (UV) region of the spectrum, and it has been proposed that these compounds function as UV filters. We demonstrate that the DNA in Zea mays plants that contain flavonoids (primarily anthocyanins) is protected from the induction of damage caused by UV radiation relative to the DNA in plants that are genetically deficient in these compounds. DNA damage was measured with a sensitive and simple assay using individual monoclonal antibodies, one specific for cyclobutane pyrimidine dimer damage and the other specific for pyrimidine(6,4)pyrimidone damage. (author)

Biotransformation of Flavonoid Conjugates with Fatty Acids and Evaluations of Their Functionalities

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Cynthia Q. Sun

2017-11-01

Full Text Available Enzymatic conjugation with fatty acids including omega-3 polyunsaturated fatty acids (ω-3 PUFAs derived from fish oil to three citrus fruit-derived flavonoids: grapefruit extract, naringin, and neohesperidin dihydrochalcone were investigated. The conversions were achieved over 85% under the catalysis of lipase Novozyme 435 in acetone at 45°C at semi-preparative scale. The conjugates were purified via solvent partition and silica gel chromatography and achieved 90–98% in purity. The NMR analysis of the conjugates confirmed that the fatty acid carbon chain was linked onto the primary –OH group on the glucose moiety of the flavonoids. The purified flavonoid conjugates alongside their original flavonoids were analyzed for antioxidant activities via 2,2-diphenyl-1-picrylhydrazyl scavenging assay, and anti-peroxidation test via peroxide values measured during a 1-week fish oil storage trial. Vascular endothelial growth factor (VEGF assay was conducted with 1, 10, and 100 μM of naringin and grapefruits and their conjugates, respectively, and total VEGF levels were measured at 24 and 48 h, respectively, using ELISA and dot blot analysis. The results from these functionality experiments demonstrated that flavonoid FA conjugates have at least comparable (if not higher antioxidant activity, anti-peroxidation activity, and anti-angiogenic activity.

Site-specific accumulation and dynamic change of flavonoids in Apocyni Veneti Folium.

Science.gov (United States)

Chen, Cui-Hua; Xu, Hu; Liu, Xun-Hong; Zou, Li-Si; Wang, Mei; Liu, Zi-Xiu; Fu, Xing-Sheng; Zhao, Hui; Yan, Ying

2017-12-01

Site-specific accumulation of flavonoids in Apocyni Veneti Folium was determined by laser scanning confocal microscope (LSCM) and the localization of catechins also was observed via vanillin-HCl staining under the conventional optical microscope. The contents of five flavonoids in Apocyni Veneti Folium from different harvest times and growth parts were measured using HPLC method. LSCM observation showed that flavonoids are accumulated in cuticle of epidermal cells and vessel walls, especially in protoplasts and nucleolus of the collenchyma cells and the epidermal cells. Catechins are localized in the palisade parenchyma cells and vessel walls, particularly in the laticifers found in the phloem. On the basis of the difference of the maximal emission wavelength between quercetin and kaempferol derivatives which have fluorescence behavior by appropriate treatment, kaempferol and its derivatives are localized exclusively in the cuticle. Results showed that the content of astragalin in Apocyni Veneti Folium from different parts revealed the decreasing trend, while hyperin and isoquercitrin were higher in June and July analyzed by HPLC. In summary, the site-specific accumulation of flavonoids in Apocyni Veneti Folium can be determined by LSCM and vanillin-HCl staining. The contents of flavonoids in Apocyni Veneti Folium are correlated with harvest times and growth parts. © 2017 Wiley Periodicals, Inc.

Comparative mutagenesis of plant flavonoids in microbial systems

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Hardigree, A.A.; Epler, J.L.

1978-01-01

The plant flavonoids quercetin (3,5,7,3',4'-pentahydroxyflavone), morin (3,5,7,2'4'-pentahydroxyflavone), kaempferol (3,5,7,4'tetrahydroxyflavone), chrysin (5,7-dihydroxyflavone), fisetin (3,7,3',4'-tetrahydroxyflavone), myricetin (3,5,7,3',4',5'-hexahydroxyflavone), myricitrin (myricetin-3-rhamnoside), hesperetin (3',5,7-trihydroxy-4'-methoxyflavanone), quercitrin (quercetin-3-L-rhamnoside), rutin (quercetin-3-rhamnosylglucoside or quercetin-3-rutinoside), and hesperidin (hesperetin-7-rutinoside) have been assayed for mutagenicity in the Salmonella/microsomal activation system. Quercetin, morin, kaempferol, fisetin, myricetin, quercitrin and rutin were mutagenic in the histidine reversion system with the frameshift strain TA98. The flavonols quercetin and myricetin are mutagenic without metabolic activation, although more effective when a rat liver microsomal preparation (S-9) is included; all others require metabolic activation. Flavonoids are common constituents of higher plants, with extensive medical uses. In addition to pure compounds, we have examined crude extracts of tobacco (snuff) and extracts from commonly available nutritional supplements containing rutin. Mutagenic activity can be detected and is correlated with the flavonoid content.

Antiherpetic activity of a flavonoid fraction from Ocotea notata leaves

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Rafael Garrett

2012-01-01

Full Text Available This study describes the isolation of a flavonoid fraction from leaves of Ocotea notata (Nees & Mart. Mez, Lauraceae, the identification of six major compounds (an A-type proanthocyanidin trimer [3], isoquercitrin [4], reynoutrin [5], miquelianin [6], quercitrin [7], afzelin [8] and four minor compounds (catechin [1], epicatechin [2], quercetin [9], kaempferol [10] present in the fraction and its activity against the Herpes simplex virus type 1 (HSV-1 and type 2 (HSV-2. The 50% effective concentrations values (EC50 calculated from the dose-response curve and the selectivity indices (SI against the virus were: EC50 35.8 µg/mL and SI 5.5 to HSV-1 and EC50 23.5 µg/mL and SI 8.5 to HSV-2. The flavonoid fraction was more active against HSV-2 than HSV-1. The mechanisms of antiviral action of the flavonoid fraction against the virus were also evaluated. The percentage inhibition (PI obtained for HSV-2 was higher than 90% in the following assays: virucidal, pre-treatment of cells, treatment of cells after viral adsorption and treatment of cells after viral penetration. For HSV-1, the flavonoid fraction had no effect in pre-treatment of cells and showed 60% of inhibition in virucidal assay.

Antiherpetic activity of a flavonoid fraction from Ocotea notata leaves

Directory of Open Access Journals (Sweden)

Rafael Garrett

2012-04-01

Full Text Available This study describes the isolation of a flavonoid fraction from leaves of Ocotea notata (Nees & Mart. Mez, Lauraceae, the identification of six major compounds (an A-type proanthocyanidin trimer [3], isoquercitrin [4], reynoutrin [5], miquelianin [6], quercitrin [7], afzelin [8] and four minor compounds (catechin [1], epicatechin [2], quercetin [9], kaempferol [10] present in the fraction and its activity against the Herpes simplex virus type 1 (HSV-1 and type 2 (HSV-2. The 50% effective concentrations values (EC50 calculated from the dose-response curve and the selectivity indices (SI against the virus were: EC50 35.8 µg/mL and SI 5.5 to HSV-1 and EC50 23.5 µg/mL and SI 8.5 to HSV-2. The flavonoid fraction was more active against HSV-2 than HSV-1. The mechanisms of antiviral action of the flavonoid fraction against the virus were also evaluated. The percentage inhibition (PI obtained for HSV-2 was higher than 90% in the following assays: virucidal, pre-treatment of cells, treatment of cells after viral adsorption and treatment of cells after viral penetration. For HSV-1, the flavonoid fraction had no effect in pre-treatment of cells and showed 60% of inhibition in virucidal assay.

Molecular displacement of warfarin from human serum albumin by flavonoid aglycones

International Nuclear Information System (INIS)

Poór, Miklós; Li, Yin; Kunsági-Máté, Sándor; Petrik, József; Vladimir-Knežević, Sanda; Kőszegi, Tamás

2013-01-01

The well-known 4-hydroxycoumarin derivative warfarin is a widespread anticoagulant drug. Besides its strong albumin binding property warfarin has a narrow therapeutic window. Therefore, a few percent of displacement from albumin can result in serious biological consequences. The flavonoid molecular group also shows very strong plasma albumin binding characteristics occupying the same binding site. It is plausible to hypothesize that flavonoid aglycones may be able to displace warfarin from human serum albumin (HSA). In our study the competing activities of different flavone (acacetin, apigenin, chrysin, luteolin), flavonol (galangin, quercetin) and flavanone (hesperetin, naringenin) aglycones were investigated using fluorescence spectroscopy. Our results represent that flavonoids are able to displace warfarin from the surface of HSA. On the other hand, when comparing flavone or flavonol groups to flavanones the latter group seems to be much weaker competitor. These observations were also supported by calculation of stability constants. Our investigations strongly suggest that we should reckon with the described molecular displacement. However, further in vivo studies are needed to support the findings of our model system. -- Highlights: • Various flavonoids are able to displace warfarin from human serum albumin. • Flavones and flavonols are much more effective competitors than flavanones. • Even 300 nM aglycone concentrations show the interaction with 3 μM warfarin. • Flavonoid pairs show quasi-additive desorbing property. • Flavones and flavonols are much stronger competitors than the examined drugs

Molecular displacement of warfarin from human serum albumin by flavonoid aglycones

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Poór, Miklós [Institute of Laboratory Medicine, University of Pécs, Pécs H-7624 (Hungary); Li, Yin; Kunsági-Máté, Sándor [Department of General and Physical Chemistry, University of Pécs, Pécs H-7624 (Hungary); János Szentágothai Research Center, H-7624 Pécs (Hungary); Petrik, József [Department of Medical Biochemistry and Hematology, Faculty of Pharmacy and Biochemistry, University of Zagreb, HR-10000 Zagreb (Croatia); Vladimir-Knežević, Sanda [Department of Pharmacognosy, Faculty of Pharmacy and Biochemistry, University of Zagreb, HR-10000 Zagreb (Croatia); Kőszegi, Tamás, E-mail: koszegit@freemail.hu [Institute of Laboratory Medicine, University of Pécs, Pécs H-7624 (Hungary)

2013-10-15

The well-known 4-hydroxycoumarin derivative warfarin is a widespread anticoagulant drug. Besides its strong albumin binding property warfarin has a narrow therapeutic window. Therefore, a few percent of displacement from albumin can result in serious biological consequences. The flavonoid molecular group also shows very strong plasma albumin binding characteristics occupying the same binding site. It is plausible to hypothesize that flavonoid aglycones may be able to displace warfarin from human serum albumin (HSA). In our study the competing activities of different flavone (acacetin, apigenin, chrysin, luteolin), flavonol (galangin, quercetin) and flavanone (hesperetin, naringenin) aglycones were investigated using fluorescence spectroscopy. Our results represent that flavonoids are able to displace warfarin from the surface of HSA. On the other hand, when comparing flavone or flavonol groups to flavanones the latter group seems to be much weaker competitor. These observations were also supported by calculation of stability constants. Our investigations strongly suggest that we should reckon with the described molecular displacement. However, further in vivo studies are needed to support the findings of our model system. -- Highlights: • Various flavonoids are able to displace warfarin from human serum albumin. • Flavones and flavonols are much more effective competitors than flavanones. • Even 300 nM aglycone concentrations show the interaction with 3 μM warfarin. • Flavonoid pairs show quasi-additive desorbing property. • Flavones and flavonols are much stronger competitors than the examined drugs.

Linkage and related analyses of Barrett's esophagus and its associated adenocarcinomas.

Science.gov (United States)

Sun, Xiangqing; Elston, Robert; Falk, Gary W; Grady, William M; Faulx, Ashley; Mittal, Sumeet K; Canto, Marcia I; Shaheen, Nicholas J; Wang, Jean S; Iyer, Prasad G; Abrams, Julian A; Willis, Joseph E; Guda, Kishore; Markowitz, Sanford; Barnholtz-Sloan, Jill S; Chandar, Apoorva; Brock, Wendy; Chak, Amitabh

2016-07-01

Familial aggregation and segregation analysis studies have provided evidence of a genetic basis for esophageal adenocarcinoma (EAC) and its premalignant precursor, Barrett's esophagus (BE). We aim to demonstrate the utility of linkage analysis to identify the genomic regions that might contain the genetic variants that predispose individuals to this complex trait (BE and EAC). We genotyped 144 individuals in 42 multiplex pedigrees chosen from 1000 singly ascertained BE/EAC pedigrees, and performed both model-based and model-free linkage analyses, using S.A.G.E. and other software. Segregation models were fitted, from the data on both the 42 pedigrees and the 1000 pedigrees, to determine parameters for performing model-based linkage analysis. Model-based and model-free linkage analyses were conducted in two sets of pedigrees: the 42 pedigrees and a subset of 18 pedigrees with female affected members that are expected to be more genetically homogeneous. Genome-wide associations were also tested in these families. Linkage analyses on the 42 pedigrees identified several regions consistently suggestive of linkage by different linkage analysis methods on chromosomes 2q31, 12q23, and 4p14. A linkage on 15q26 is the only consistent linkage region identified in the 18 female-affected pedigrees, in which the linkage signal is higher than in the 42 pedigrees. Other tentative linkage signals are also reported. Our linkage study of BE/EAC pedigrees identified linkage regions on chromosomes 2, 4, 12, and 15, with some reported associations located within our linkage peaks. Our linkage results can help prioritize association tests to delineate the genetic determinants underlying susceptibility to BE and EAC.

Determination of flavonoids in plant material by HPLC with diode-array and electro-array detections.

Science.gov (United States)

Mattila, P; Astola, J; Kumpulainen, J

2000-12-01

A high-performance liquid chromatographic (HPLC) method with in-line connected diode-array (DAD) and electro-array (EC) detection to identify and quantify 17 flavonoids in plant-derived foods is described. Catechins were extracted from the samples using ethyl acetate, and quantification of these compounds was performed with the EC detector. Other flavonoids were quantified with DAD after acid hydrolysis. The methods developed were effective for the determination of catechins and other flavonoids in plant-derived foods. Responses of the detection systems were linear within the range evaluated, 20-200 ng/injection (DAD) and 20-100 ng/injection (EC), with correlation coefficients exceeding 0.999. Coefficient of variation was under 10.5%, and recoveries of flavonoids ranged from 70 to 124%. Purity of the flavonoid peaks was confirmed by combining the spectral and voltammetric data.

Dirhamnosyl flavonoid and other constituents from Brillantaisia palisatii

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Berrondo, Luciane Fatima; Gabriel, Felipe Teixeira; Fernandes, Sidney Bessa de; Menezes, Fabio de Sousa [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Farmacia. Dept. de Produtos Naturais e Alimentos]. E-mail: fsmenezes@pharma.ufrj.br; Moreira, Davyson de Lima [Universidade de Barra Mansa, RJ (Brazil). Faculdade de Farmacia

2003-12-01

A mixture containing sitosterol and stigmasterol; a new triterpene 3-epi-ursolic acid; another triterpene mixture comprising {alpha}-amyrin, {beta}-amyrin and lupeol; verbascoside, a phenylpropanoid glycoside; and lespedin, a glycosyl flavonoid, were isolated. The less polar compounds (steroids and triterpenoids) were isolated from the hexane partition of the crude ethanolic extract while the more polar ones (phenylpropanoid glycoside and glycosyl flavonoid) were isolated from the ethyl acetate partition of the same extract. The structures of all compounds were established using modern spectrometric methods of elucidation. The spectroscopic data of Lespedin, a rare dirhamnosylflavonol with hypotensor activity and of the triterpene, 3-epi-ursolic acid, are also reported. (author)

Primula latifolia Lapeyr. and Primula vulgaris Hudson flavonoids.

Science.gov (United States)

Colombo, Paola S; Flamini, Guido; Fico, Gelsomina

2014-01-01

Three flavonoids were isolated from the leaf MeOH extracts of Primula latifolia Lapeyr. and Primula vulgaris Hudson collected from Italian Alps: rutin (1) and kaempferol 3-neohesperidoside (2) from P. latifolia, and kaempferol 3-β-O-glucopyranosyl-(1 → 2) gentiobioside (3) from P. vulgaris. The structures were assigned on the basis of their (1)H and (13)C NMR data, including those derived from 2D NMR, as well as on HPLC-MS results. This article is the first to report on P. vulgaris tissue flavonoids after Harborne's study in 1968 and the first work ever on these compounds from P. latifolia.

PHYSIOLOGICAL AND MEDICAL EFFECTS OF PLANT FLAVONOID QUERCETIN

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Aneta Štochmaľová

2013-02-01

Full Text Available Flavonoid compounds in vegetable-based diets bring a significant contribution to the role of fruits and vegetables as health-promoting foods. This review summarizes the available data concerning physiological and therapeutical effect of plan flavonoid quercetin. Quercetin has a number of beneficial influence on health because of their antioxidant, anti-inflammatory, anti-proliferative, anti-carcinogenic and anti-diabetes properties. Effects of quercetin have been explained by its interference with cellular enzymes, receptors, transporters and signal transduction systems. Despite the available data reviewed here, the targets, effects, absorption, metabolism and areas of practical application of quercetin are still poorly understood, therefore further studies in this areas are required.

Regulation of NF-κB activity in astrocytes: effects of flavonoids at dietary-relevant concentrations

International Nuclear Information System (INIS)

Spilsbury, Alison; Vauzour, David; Spencer, Jeremy P.E.; Rattray, Marcus

2012-01-01

Highlights: ► We tested the hypothesis that low concentrations of flavonoids inhibit NF-κB in astrocytes. ► Primary cultured astrocytes possess a functional κB-system, measured using luciferase assays. ► Seven flavonoids (100 nM–1 μM) failed to reduce NF-κB activity in astrocytes. ► Four flavonoids (100 nM–1 μM) failed to reduce TNFa-stimulated NF-κB activity in astrocytes. ► (−)-Epicatechin did not regulate nuclear translocation of the NF-κB subunit, p65. -- Abstract: Neuroinflammation plays an important role in the progression of neurodegenerative disorders such as Alzheimer’s disease and Parkinson’s disease. Sustained activation of nuclear transcription factor κB (NF-κB) is thought to play an important role in the pathogenesis of neurodegenerative disorders. Flavonoids have been shown to possess antioxidant and anti-inflammatory properties and we investigated whether flavonoids, at submicromolar concentrations relevant to their bioavailability from the diet, were able to modulate NF-κB signalling in astrocytes. Using luciferase reporter assays, we found that tumour necrosis factor (TNFα, 150 ng/ml) increased NF-κB-mediated transcription in primary cultures of mouse cortical astrocytes, which was abolished on co-transfection of a dominant-negative IκBα construct. In addition, TNFα increased nuclear localisation of p65 as shown by immunocytochemistry. To investigate potential flavonoid modulation of NF-κB activity, astrocytes were treated with flavonoids from different classes; flavan-3-ols ((−)-epicatechin and (+)-catechin), flavones (luteolin and chrysin), a flavonol (kaempferol) or the flavanones (naringenin and hesperetin) at dietary-relevant concentrations (0.1–1 μM) for 18 h. None of the flavonoids modulated constitutive or TNFα-induced NF-κB activity. Therefore, we conclude that NF-κB signalling in astrocytes is not a major target for flavonoids.

Differential accumulation of flavonoids by tomato (Solanum ...

African Journals Online (AJOL)

SARAH

2014-12-29

Dec 29, 2014 ... Objective: Little is known about physiological functions of flavonoids, specifically in the course of maturation ... epicarp (especially naringenin) with the onset of the ripening. ..... the University of Chemical Technology and.

Testing association and linkage using affected-sib-parent study designs.

Science.gov (United States)

Millstein, Joshua; Siegmund, Kimberly D; Conti, David V; Gauderman, W James

2005-11-01

We have developed a method for jointly testing linkage and association using data from affected sib pairs and their parents. We specify a conditional logistic regression model with two covariates, one that quantifies association (either direct association or indirect association via linkage disequilibrium), and a second that quantifies linkage. The latter covariate is computed based on expected identity-by-descend (ibd) sharing of marker alleles between siblings. In addition to a joint test of linkage and association, our general framework can be used to obtain a linkage test comparable to the mean test (Blackwelder and Elston [1985] Genet. Epidemiol. 2:85-97), and an association test comparable to the Family-Based Association Test (FBAT; Rabinowitz and Laird [2000] Hum. Hered. 50:211-223). We present simulation results demonstrating that our joint test can be more powerful than some standard tests of linkage or association. For example, with a relative risk of 2.7 per variant allele at a disease locus, the estimated power to detect a nearby marker with a modest level of LD was 58.1% by the mean test (linkage only), 69.8% by FBAT, and 82.5% by our joint test of linkage and association. Our model can also be used to obtain tests of linkage conditional on association and association conditional on linkage, which can be helpful in fine mapping. Copyright 2005 Wiley-Liss, Inc.

Antioxidant-capacity-based models for the prediction of acrylamide reduction by flavonoids.

Science.gov (United States)

Cheng, Jun; Chen, Xinyu; Zhao, Sheng; Zhang, Yu

2015-02-01

The aim of this study was to investigate the applicability of artificial neural network (ANN) and multiple linear regression (MLR) models for the estimation of acrylamide reduction by flavonoids, using multiple antioxidant capacities of Maillard reaction products as variables via a microwave food processing workstation. The addition of selected flavonoids could effectively reduce acrylamide formation, which may be closely related to the number of phenolic hydroxyl groups of flavonoids (R: 0.735-0.951, Pcapacity (ΔTEAC) measured by DPPH (R(2)=0.833), ABTS (R(2)=0.860) or FRAP (R(2)=0.824) assay. Both ANN and MLR models could effectively serve as predictive tools for estimating the reduction of acrylamide affected by flavonoids. The current predictive model study provides a low-cost and easy-to-use approach to the estimation of rates at which acrylamide is degraded, while avoiding tedious sample pretreatment procedures and advanced instrumental analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Different flavonoids present in the micronized purified flavonoid fraction (Daflon 500 mg) contribute to its anti-hyperpermeability effect in the hamster cheek pouch microcirculation.

Science.gov (United States)

Paysant, J; Sansilvestri-Morel, P; Bouskela, E; Verbeuren, T J

2008-02-01

This study evaluated microcirculatory effects of the flavonoid substances that constitute the micronized purified flavonoid fraction (MPFF) (Daflon 500 mg) in comparison to diosmin. In groups of 3 male hamsters, oral treatment with MPFF or diosmin (15 min before anesthesia) did not alter blood pressure. At 10 or 30 mg/kg, both MPFF and diosmin significantly decreased the leaky sites caused by ischemia/reperfusion (I/R) (30 min) in the hamster cheek pouch; the effect was significantly higher with MPFF (39+/-1% and 52+/-1%, respectively) than diosmin (18+/-1% and 37+/-3%, respectively). Eight groups of 3 hamsters each were treated with the components of MPFF. Diosmetin only decreased the number leaky sites at 30 mg/kg (decrease: 15+/-2%). The decrement at 10 and 30 mg/kg averaged at: 17+/-3% and 44+/-1%, respectively, for hesperidin; 19+/-1% and 46+/-2%, respectively, for linarin; and 30+/-1% and 44+/-1%, respectively, for isorhoifolin. Hesperidin, linarin, and isorhoifolin each displayed an anti-leakage effect comparable to or greater than diosmin. MPFF decreases permeability more than any of its single constituents, suggesting that the flavonoids present in its formulation have a synergistic action. These results illustrate that MPFF is more potent than single diosmin in this model of hyperpermeability and that each of the flavonoid substances present in MPFF contribute to its action.

Flavonoids as scavengers of nitric oxide radical.

NARCIS (Netherlands)

van Acker, S.A.B.E.; Tromp, M.N.J.L.; Haenen, G.R.M.M.; van der Vijgh, W.J.F.; Bast, A.

1995-01-01

Flavonoids are a group of naturally occurring compounds used, e.g., in the treatment of vascular endothelial damage. They are known to be excellent scavengers of oxygen free radicals. Since the nitric oxide radical (

Privacy-preserving record linkage on large real world datasets.

Science.gov (United States)

Randall, Sean M; Ferrante, Anna M; Boyd, James H; Bauer, Jacqueline K; Semmens, James B

2014-08-01

Record linkage typically involves the use of dedicated linkage units who are supplied with personally identifying information to determine individuals from within and across datasets. The personally identifying information supplied to linkage units is separated from clinical information prior to release by data custodians. While this substantially reduces the risk of disclosure of sensitive information, some residual risks still exist and remain a concern for some custodians. In this paper we trial a method of record linkage which reduces privacy risk still further on large real world administrative data. The method uses encrypted personal identifying information (bloom filters) in a probability-based linkage framework. The privacy preserving linkage method was tested on ten years of New South Wales (NSW) and Western Australian (WA) hospital admissions data, comprising in total over 26 million records. No difference in linkage quality was found when the results were compared to traditional probabilistic methods using full unencrypted personal identifiers. This presents as a possible means of reducing privacy risks related to record linkage in population level research studies. It is hoped that through adaptations of this method or similar privacy preserving methods, risks related to information disclosure can be reduced so that the benefits of linked research taking place can be fully realised. Copyright © 2013 Elsevier Inc. All rights reserved.

Antidepressant screening and flavonoids isolation from ...

African Journals Online (AJOL)

Eremostachys laciniata (L) Bunge (Lamiaceae), a rich source of flavonoids, has been investigated for chemical constituents and in vivo antidepressant property using forced swim test (FST) model. Five important compounds were isolated, including luteolin (1), apigenin (2), 5,8-dihydroxy-6,7- dimethoxyflavone (3), 5 ...

Flavonoid glycosides from Erythroxylum pulchrum A. St.-Hil. (Erythroxylaceae); Flavonoides glicosilados de Erythroxylum pulchrum A. St.-Hil. (Erythroxylaceae)

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Albuquerque, Camila Holanda de; Tavares, Josean Fechine; Oliveira, Steno Lacerda de; Silva, Taina Souza; Costa, Vicente Carlos de Oliveira; Silva, Marcelo Sobral da, E-mail: josean@ltf.ufpb.br [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Centro de Ciencias da Saude. Departamento de Ciencias Farmaceuticas; Goncalves, Gregorio Fernandes; Pessoa, Hilzeth de Luna Freire [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Centro de Ciencias da Saude. Dept. de Biologica Molecular; Agra, Maria de Fatima [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Centro de Biotecnologia. Departamento de Biotecnologia

2014-07-01

The phytochemical investigation of Erythroxylum pulchrum St. Hil. (Erythroxylaceae) led to the isolation of three known flavonoid glycosides quercetin-3-O-α-L-rhaminoside, ombuin-3-ruthinoside and ombuin-3-ruthinoside-5-glucoside. These flavonoids are being described for the first time in this E. pulchrum. The structures of the compounds were determined by analysis of IR, MS and NMR data, as well as by comparison with literature data. The methanolic extract of leaves from E. pulchrum inhibited the growth of the Bacillus subtilis CCT 0516, Escherichia coli ATCC 2536, Pseudomonas aeruginosa ATCC 8027, P. aeruginosa ATCC 25619, Staphylococcus aureus ATCC 6538, S. aureus ATCC 25925, Streptococcus sanguinis ATCC 15300, S. salivarius ATCC 7073, S. mutans ATCC 25175 and Streptococcus ATCC. S. aureus ATCC 25925 was the most sensitive among the other S. sanguinis while S. salivarius proved the most resistant. (author)

Flavonoids intake and risk of prostate cancer: a meta-analysis of observational studies.

Science.gov (United States)

Guo, K; Liang, Z; Liu, L; Li, F; Wang, H

2016-12-01

The aim of the study was to assess the association between total flavonoids/flavonoid subclasses intake and prostate cancer risk. Several databases were searched to select eligible studies with predefined criteria. Risk ratios (RRs) with 95% confidence intervals (CIs) were used as the effect size. Publication bias and sensitivity analysis were performed. A total of five studies including four prospective cohort studies and one case-control study were included in the meta-analysis. The pooled result demonstrated a significantly increased risk of prostate cancer with higher intake of total flavonoids (RR = 1.12, 95% CI: 1.02-1.23, P = 0.013). However, sensitivity analysis indicated that there lacked a significant association after removing the study of Wang et al. (RR = 1.17, 95% CI: 0.94-1.46). Subgroup analysis stratified by flavonoids subclasses found that higher intake of anthocyanidins and flavan-3-ols were significantly associated with increased prostate cancer risk (RR = 1.12, 95% CI: 1.03-1.21, P = 0.011; RR = 1.21, 95% CI: 1.10-1.32, P flavonoids may not be associated with prostate cancer risk. © 2016 Blackwell Verlag GmbH.

Quantitative Structure – Antioxidant Activity Relationships of Flavonoid Compounds

Directory of Open Access Journals (Sweden)

Károly Héberger

2004-12-01

Full Text Available A quantitative structure – antioxidant activity relationship (QSAR study of 36 flavonoids was performed using the partial least squares projection of latent structures (PLS method. The chemical structures of the flavonoids have been characterized by constitutional descriptors, two-dimensional topological and connectivity indices. Our PLS model gave a proper description and a suitable prediction of the antioxidant activities of a diverse set of flavonoids having clustering tendency.

Isolation of flavonoids from apple peel using novel graphene oxide cotton fiber.

Science.gov (United States)

Xu, Z; Peng, R; Chen, X; Ghosh, R; Rupasinghe, H P V

2017-11-01

A novel graphene oxide cotton fibre (GOF) was used to adsorb flavonoids from crude ethanol extracts derived from apple peels. Ultra-high pressure liquid chromatography-mass spectrometry was used to analyse polyphenol content, and the resulting data demonstrated that GOF-based flash chromatography can be used to efficiently separate polyphenols from sugars and can facilitate the removal of 95% of the sugar content. Flavonoids can be easily separated from phenolic acids. Chalcones and flavonols were eluted with 100% methanol and subsequently flavan-3-ols can be eluted with 0.04 M sodium hydroxide. The novel GOF has the potential to be used in the isolation of flavonoids.

HL-60 differentiating activity and flavonoid content of the readily extractable fraction prepared from citrus juices.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

1999-01-01

Citrus plants are rich sources of various bioactive flavonoids. To eliminate masking effects caused by hesperidin, naringin, and neoeriocitrin, the abundant flavonoid glycosides which make up 90% of the conventionally prepared sample, the readily extractable fraction from Citrus juice was prepared by adsorbing on HP-20 resin and eluting with EtOH and acetone from the resin and was subjected to HL-60 differentiation assay and quantitative analysis of major flavonoids. Screening of 34 Citrus juices indicated that King (C. nobilis) had a potent activity for inducing differentiation of HL-60, and the active principles were isolated and identified as four polymethoxylated flavonoids, namely, nobiletin, 3,3',4',5,6,7, 8-heptamethoxyflavone, natsudaidain, and tangeretin. HPLC analysis of the readily extractable fraction also indicated that King contained high amounts of these polymethoxylated flavonoids among the Citrus juices examined. Principal component and cluster analyses of the readily extractable flavonoids indicated peculiarities of King and Bergamot.

Factors modulating bioavailability of quercetin-related flavonoids and the consequences of their vascular function.

Science.gov (United States)

Terao, Junji

2017-09-01

Nowadays dietary flavonoids attract much attention in the prevention of chronic diseases. Epidemiological and intervention studies strongly suggest that flavonoid intake has beneficial effects on vascular health. It is unlikely that flavonoids act as direct antioxidants, although oxidative stress profoundly contributes to vascular impairment leading to cardiovascular diseases. Instead, flavonoids may exert their function by tuning the cellular redox state to an adaptive response or tolerable stress. However, the optimum intake of flavonoids from supplements or diet has not been clarified yet, because a number of exogenous and endogenous factors modulating their bioavailability affect their vascular function. This review will focus on the current knowledge of the bioavailability and vascular function of quercetin as a representative of antioxidative flavonoids. Current intervention studies imply that intake of quercetin-rich onion improves vascular health. Onion may be superior to quercetin supplement from the viewpoint of quercetin bioavailability, probably because the food matrix enhances the intestinal absorption of quercetin. α-Glucosylation increases its bioavailability by elevating the accessibility to the absorptive cells. Prenylation may enhance bioaccumulation at the target site by increasing the cellular uptake. However, these chemical modifications do not guarantee health benefits to the vascular system. Dietary quercetin is exclusively present as their conjugated form in the blood stream. Quercetin may exert its vascular function as an aglycone within macrophage cells after inflammation-induced deconjugation and as conjugated metabolites by targeting endothelial cells. The relationship between the bioavailability and bio-efficacy should be clarified, to evaluate the vascular function of a wide variety of dietary flavonoids. Copyright © 2017 Elsevier Inc. All rights reserved.

Genome-wide linkage analysis for human longevity

DEFF Research Database (Denmark)

Beekman, Marian; Blanché, Hélène; Perola, Markus

2013-01-01

Clear evidence exists for heritability of human longevity, and much interest is focused on identifying genes associated with longer lives. To identify such longevity alleles, we performed the largest genome-wide linkage scan thus far reported. Linkage analyses included 2118 nonagenarian Caucasian...

Sonochemical effects on 14 flavonoids common in citrus: relation to stability.

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Liping Qiao

Full Text Available The sonochemical effects of ultrasound (US treatment on 14 flavonoids representing the main flavonoids in citrus fruit were investigated in a standard mixture by stability evaluation of a model system. Degradation products were further tentatively identified by Fourier transform infrared spectroscopy and high-performance liquid chromatography-ultraviolet detection-electrospray ionization tandem mass spectrometry. Thirteen flavonoids (i.e., eriocitrin, narirutin, neohesperidin, quercitrin, eridictyol, didymin, naringenin, luteolin, sinensetin, nobiletin, tangeretin, naringin, and hesperidin were fairly stable whereas quercetin was degraded significantly by US treatment. The types of solvent and temperature used were important factors that determined the resulting degradation reactions. The degradation rate of quercetin was highest in 80% ethanol aqueous solution and decreased with increasing temperature. Longer US durations caused increases in the extent of quercetin degradation. Liquid height, ultrasonic intensity, pulse length, and duty cycle of US affected degradation rates but did not change the nature of degradation of the flavonoids. Four types of reactions occurred simultaneously for quercetin under US treatment: oxidation, addition, polymerization, and decomposition. Eight degradation products were tentatively identified as dimer, alcohol addition, oxidation, and decomposition products.

Determination of flavonoids in cultivated sugarcane leaves, bagasse, juice and in transgenic sugarcane by liquid chromatography-UV detection.

Science.gov (United States)

Colombo, Renata; Lanças, Fernando M; Yariwake, Janete H

2006-01-20

A high-performance liquid chromatography (HPLC) method with photo-diode array (DAD) detection was developed to separate and quantify flavonoids in sugarcane leaves and bagasse (= the crushed sugarcane refuse from juice extraction), and in sugarcane juice. Sugarcane flavonoids consist of a complex mixture of aglycones and glycosides (including flavonolignan glycosides), and the HPLC-UV method herein proposed is suitable for their quantification as total flavonoids. This method was applied to analyze samples of cultivated sugarcane, commercial juice and transgenic sugarcane leaves. Sugarcane leaves proved a promising source of flavonoids: an average of 1.10 mg of total flavonoids/g plant material was found in fresh leaves. Moreover, the flavonoid content of sugarcane juice (0.6 mg/mL) is comparable to other food sources of flavonoids previously reported. Transgenic sugarcane leaves ("Bowman-Birk" and "Kunitz") were compared with non-modified ("control") plant samples using the proposed HPLC-UV method, which indicated that the content of total flavonoids in transgenic plants is different from that in non-modified sugarcane.

Determination of flavonoids, polyphenols and antioxidant activity of Tephrosia purpurea: a seasonal study.

Science.gov (United States)

Pandey, Madan Mohan; Khatoon, Sayyada; Rastogi, Subha; Rawat, Ajay Kumar Singh

2016-11-01

Tephrosia purpurea (Linn · ) Pers. is widely used in traditional medicine to treat liver disorders, febrile attacks, enlargement and obstruction of liver, spleen, and kidney. In the present study, investigations were carried out to determine the seasonal impact on the content of flavonoid glycosides and on antioxidant activities so as to identify the optimal time of harvesting. The plant materials were collected in different seasons during 2013-2014. Air-dried, powdered plant materials were extracted with 95% ethanol and ethanol: water (1:1) by ultrasound-assisted extraction process. Their chemical composition in terms of total polyphenol and flavonoid contents (TPCs and TFCs) was determined using modified colorimetric Folin-Ciocalteu method and aluminum chloride colorimetric assay respectively. To determine the in vitro antioxidant activity, diphenyl-picryl hydrazyl (DPPH) radical-scavenging assay and total antioxidant capacity by phosphomolybdate antioxidant assay were carried out. High-performance liquid chromatography (HPLC)/photo-diode array (PDA) analysis was used to quantify the flavonoid glycosides in the samples collected in different seasons. Correlation studies were also carried out between antioxidant activities and TPCs. The highest TPC and TFC were found to be in the 95% ethanolic extract of the August sample and the lowest in the 50% hydro-alcoholic extract of the plant sample collected in winter season. It was observed that in both the assays used to determine the antioxidant activity, the 95% ethanolic extracts in all the seasons showed a higher activity than their respective 50% hydro-alcoholic extracts with an increase in activity as we go from cold to hot to rainy seasons. Based on correlation analysis, DPPH radical-scavenging activities as well as the spectrophotometrically measured phosphomolybdenum complex were also strongly correlated with TPC of the extracts. The most abundant flavonoid glycoside was quercetin-3-O-rhamnoglucoside in all

Singlet Oxygen Reactions with Flavonoids. A Theoretical – Experimental Study

Science.gov (United States)

Morales, Javier; Günther, Germán; Zanocco, Antonio L.; Lemp, Else

2012-01-01

Detection of singlet oxygen emission, λmax = 1270 nm, following laser excitation and steady-state methods were employed to measure the total reaction rate constant, kT, and the reactive reaction rate constant, kr, for the reaction between singlet oxygen and several flavonoids. Values of kT determined in deuterated water, ranging from 2.4×107 M−1s−1 to 13.4×107 M−1s−1, for rutin and morin, respectively, and the values measured for kr, ranging from 2.8×105 M−1s−1 to 65.7×105 M−1s−1 for kaempferol and morin, respectively, being epicatechin and catechin chemically unreactive. These results indicate that all the studied flavonoids are good quenchers of singlet oxygen and could be valuable antioxidants in systems under oxidative stress, in particular if a flavonoid-rich diet was previously consumed. Analysis of the dependence of rate constant values with molecular structure in terms of global descriptors and condensed Fukui functions, resulting from electronic structure calculations, supports the formation of a charge transfer exciplex in all studied reactions. The fraction of exciplex giving reaction products evolves through a hydroperoxide and/or an endoperoxide intermediate produced by singlet oxygen attack on the double bond of the ring C of the flavonoid. PMID:22802966

Fine mapping quantitative trait loci under selective phenotyping strategies based on linkage and linkage disequilibrium criteria

DEFF Research Database (Denmark)

Ansari-Mahyari, S; Berg, P; Lund, M S

2009-01-01

disequilibrium-based sampling criteria (LDC) for selecting individuals to phenotype are compared to random phenotyping in a quantitative trait loci (QTL) verification experiment using stochastic simulation. Several strategies based on LAC and LDC for selecting the most informative 30%, 40% or 50% of individuals...... for phenotyping to extract maximum power and precision in a QTL fine mapping experiment were developed and assessed. Linkage analyses for the mapping was performed for individuals sampled on LAC within families and combined linkage disequilibrium and linkage analyses was performed for individuals sampled across...... the whole population based on LDC. The results showed that selecting individuals with similar haplotypes to the paternal haplotypes (minimum recombination criterion) using LAC compared to random phenotyping gave at least the same power to detect a QTL but decreased the accuracy of the QTL position. However...

Optimizing Polychlorinated Biphenyl Degradation by Flavonoid-Induced Cells of the Rhizobacterium Rhodococcus erythropolis U23A.

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Thi Thanh My Pham

Full Text Available There is evidence that many plant secondary metabolites may act as signal molecules to trigger the bacterial ability to metabolize polychlorinated biphenyls (PCBs during the rhizoremediation process. However, the bases for the PCB rhizoremediation process are still largely unknown. The rhizobacterium Rhodococcus erythropolis U23A is unable to use flavanone as a growth substrate. However, on the basis of an assay that monitors the amount of 4-chlorobenzoate produced from 4-chlorobiphenyl by cells grown co-metabolically on flavanone plus sodium acetate, this flavonoid was previously found to be a potential inducer of the U23A biphenyl catabolic pathway. In this work, and using the same assay, we identified ten other flavonoids that did not support growth, but that acted as inducers of the U23A biphenyl pathway, and we confirmed flavonoid induction of the biphenyl catabolic pathway using quantitative real-time polymerase chain reaction (RT-qPCR on the bphA gene. We also examined the effect of the growth co-substrate on flavonoid induction. Sodium acetate was replaced by glucose, mannose, sucrose, or mannitol, which are sugars found in plant root exudates. The data showed that the level of induction of strain U23A biphenyl-degrading enzymes was significantly influenced by the nature and concentration of the flavonoid in the growth medium, as well as by the substrate used for growth. Sucrose allowed for an optimal induction response for most flavonoids. Some flavonoids, such as flavone and isoflavone, were better inducers of the biphenyl catabolic enzymes than biphenyl itself. We also found that all flavonoids tested in this work were metabolized by strain U23A during co-metabolic growth, but that the metabolite profiles, as well as the level of efficiency of degradation, differed for each flavonoid. To obtain insight into how flavonoids interact with strain U23A to promote polychlorinated biphenyl (PCB degradation, we determined the concentration of

Flavonoid profiling and nodulation of some legumes in response to the allelopathic stress of Sonchus oleraceus L.

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Nasr Hassan Gomaa

2015-12-01

Full Text Available Annual sowthistle (Sonchus oleraceus has been reported to produce allelopathic effects. Two greenhouse experiments were conducted to estimate the allelopathic potential of both plant residue and root exudates of S. oleraceus on flavonoid composition and nodulation in a leguminous crop, Trifolium alexandrinum, and in two leguminous weeds, Melilotus indicus and T. resupinatum. The results of high performance liquid chromatography-mass spectrometry (HPLC-MS/MS showed that all three legumes contained six flavonoid aglycones: apigenin, daidzein, kaempferol, luteolin, myricetin and quercetin; and seven flavonoid glycosides: daidzin, genistin, hesperidin, hyperoside, kaempferol-7-O-glucoside, naringin and rutin. In general, both plant residue and root exudates had inhibitory effects on the flavonoid composition and nodulation of the target species. However, residue of S. oleraceus caused a significant increase in both individual and total detected flavonoids in T. alexandrinum. The results suggest that the phytotoxins released from S. oleraceus may restrain the biosynthesis of flavonoids in the target species, whereas the accumulated flavonoids in T. alexandrinum are allelopathic-induced metabolites and suggest a resistance mode in this crop.

Estimating parameters for probabilistic linkage of privacy-preserved datasets.

Science.gov (United States)

Brown, Adrian P; Randall, Sean M; Ferrante, Anna M; Semmens, James B; Boyd, James H

2017-07-10

Probabilistic record linkage is a process used to bring together person-based records from within the same dataset (de-duplication) or from disparate datasets using pairwise comparisons and matching probabilities. The linkage strategy and associated match probabilities are often estimated through investigations into data quality and manual inspection. However, as privacy-preserved datasets comprise encrypted data, such methods are not possible. In this paper, we present a method for estimating the probabilities and threshold values for probabilistic privacy-preserved record linkage using Bloom filters. Our method was tested through a simulation study using synthetic data, followed by an application using real-world administrative data. Synthetic datasets were generated with error rates from zero to 20% error. Our method was used to estimate parameters (probabilities and thresholds) for de-duplication linkages. Linkage quality was determined by F-measure. Each dataset was privacy-preserved using separate Bloom filters for each field. Match probabilities were estimated using the expectation-maximisation (EM) algorithm on the privacy-preserved data. Threshold cut-off values were determined by an extension to the EM algorithm allowing linkage quality to be estimated for each possible threshold. De-duplication linkages of each privacy-preserved dataset were performed using both estimated and calculated probabilities. Linkage quality using the F-measure at the estimated threshold values was also compared to the highest F-measure. Three large administrative datasets were used to demonstrate the applicability of the probability and threshold estimation technique on real-world data. Linkage of the synthetic datasets using the estimated probabilities produced an F-measure that was comparable to the F-measure using calculated probabilities, even with up to 20% error. Linkage of the administrative datasets using estimated probabilities produced an F-measure that was higher

RLT-S: A Web System for Record Linkage.

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Abdullah-Al Mamun

Full Text Available Record linkage integrates records across multiple related data sources identifying duplicates and accounting for possible errors. Real life applications require efficient algorithms to merge these voluminous data sources to find out all records belonging to same individuals. Our recently devised highly efficient record linkage algorithms provide best-known solutions to this challenging problem.We have developed RLT-S, a freely available web tool, which implements our single linkage clustering algorithm for record linkage. This tool requires input data sets and a small set of configuration settings about these files to work efficiently. RLT-S employs exact match clustering, blocking on a specified attribute and single linkage based hierarchical clustering among these blocks.RLT-S is an implementation package of our sequential record linkage algorithm. It outperforms previous best-known implementations by a large margin. The tool is at least two times faster for any dataset than the previous best-known tools.RLT-S tool implements our record linkage algorithm that outperforms previous best-known algorithms in this area. This website also contains necessary information such as instructions, submission history, feedback, publications and some other sections to facilitate the usage of the tool.RLT-S is integrated into http://www.rlatools.com, which is currently serving this tool only. The tool is freely available and can be used without login. All data files used in this paper have been stored in https://github.com/abdullah009/DataRLATools. For copies of the relevant programs please see https://github.com/abdullah009/RLATools.

Linkage analysis: Inadequate for detecting susceptibility loci in complex disorders?

Energy Technology Data Exchange (ETDEWEB)

Field, L.L.; Nagatomi, J. [Univ. of Calgary, Alberta (Canada)

1994-09-01

Insulin-dependent diabetes mellitus (IDDM) may provide valuable clues about approaches to detecting susceptibility loci in other oligogenic disorders. Numerous studies have demonstrated significant association between IDDM and a VNTR in the 5{prime} flanking region of the insulin (INS) gene. Paradoxically, all attempts to demonstrate linkage of IDDM to this VNTR have failed. Lack of linkage has been attributed to insufficient marker locus information, genetic heterogeneity, or high frequency of the IDDM-predisposing allele in the general population. Tyrosine hydroxylase (TH) is located 2.7 kb from INS on the 5` side of the VNTR and shows linkage disequilibrium with INS region loci. We typed a highly polymorphic microsatellite within TH in 176 multiplex families, and performed parametric (lod score) linkage analysis using various intermediate reduced penetrance models for IDDM (including rare and common disease allele frequencies), as well as non-parametric (affected sib pair) linkage analysis. The scores significantly reject linkage for recombination values of .05 or less, excluding the entire 19 kb region containing TH, the 5{prime} VNTR, the INS gene, and IGF2 on the 3{prime} side of INS. Non-parametric linkage analysis also provided no significant evidence for linkage (mean TH allele sharing 52.5%, P=.12). These results have important implications for efforts to locate genes predisposing to complex disorders, strongly suggesting that regions which are significantly excluded by linkage methods may nevertheless contain predisposing genes readily detectable by association methods. We advocate that investigators routinely perform association analyses in addition to linkage analyses.

Sinapate esters provide greater UV-B attenuation than flavonoids in Arabidopsis thaliana (Brassicaceae)

International Nuclear Information System (INIS)

Sheahan, J.J.

1996-01-01

Mutants affected in flavonoid (tt4) or sinapate ester (fah1) biosynthesis were used to assess the relative importance of these phenolic UV photoprotectants in Arabidopsis. Flavonoid and sinapate ester absorption was more specific for UV-B than major nonphenolic chromophores in crude extracts. A new method of evaluating phenolic UV-B attenuation was developed using fluorescence analysis. When excited by UV-B, sinapate ester containing leaves and cotyledons had enhanced sinapate ester fluorescence and reduced chlorophyll fluorescence relative to those without sinapate esters. Although fluorescence analysis gave no evidence of UV-B attenuation by flavonoids, enhanced chlorophyll and protein loss were observed upon UV-B exposure in flavonoid-deficient leaves, suggesting they have another mechanism of UV-B protection. The hydroxycinnamates have been largely ignored as UV-B attenuating pigments. and the results indicate that greater attention should be paid to their role in attenuating UV-B

Flavonoids released naturally from alfalfa promote development of symbiotic glomus spores in vitro.

Science.gov (United States)

Tsai, S M; Phillips, D A

1991-05-01

Because flavonoids from legumes induce transcription of nodulation genes in symbiotic rhizobial bacteria, it is reasonable to test whether these compounds alter the development of vesicular-arbuscular mycorrhizal (VAM) fungi that infect those plants. Quercetin-3-O-galactoside, the dominant flavonoid released naturally from alfalfa (Medicago sativa L.) seeds, promoted spore germination of Glomus etunicatum and Glomus macrocarpum in vitro. Quercetin produced the maximum increases in spore germination, hyphal elongation, and hyphal branching in G. etunicatum at 1 to 2.5 muM concentrations. Two flavonoids exuded from alfalfa roots, 4',7-dihydroxyflavone and 4',7-dihydroxyflavanone, also enhanced spore germination of this fungal species. Formononetin, an isoflavone that is released from stressed alfalfa roots, inhibited germination of both Glomus species. These in vitro results suggest that plant flavonoids may facilitate or regulate the development of VAM symbioses and offer new hope for developing pure, plant-free cultures of VAM fungi.

Bioavailability of flavonoids: a review of their membrane transport and the function of bilitranslocase in animal and plant organisms.

Science.gov (United States)

Passamonti, Sabina; Terdoslavich, Michela; Franca, Raffaella; Vanzo, Andreja; Tramer, Federica; Braidot, Enrico; Petrussa, Elisa; Vianello, Angelo

2009-05-01

Fruits and vegetables are rich in flavonoids, and ample epidemiological data show that diets rich in fruits and vegetables confer protection against cardiovascular, neurodegenerative and inflammatory diseases, and cancer. However, flavonoid bioavailability is reportedly very low in mammals and the molecular mechanisms of their action are still poorly known. This review focuses on membrane transport of flavonoids, a critical determinant of their bioavailability. Cellular influx and efflux transporters are reviewed for their involvement in the absorption of flavonoids from the gastro-intestinal tract and their subsequent tissue distribution. A focus on the mammalian bilirubin transporter bilitranslocase (TCDB 2.A.65.1.1) provides further insight into flavonoid bioavailability and its relationship with plasma bilirubin (an endogenous antioxidant). The general function of bilitranslocase as a flavonoid membrane transporter is further demonstrated by the occurrence of a plant homologue in organs (petals, berries) where flavonoid biosynthesis is most active. Bilitranslocase appears associated with sub-cellular membrane compartments and operates as a flavonoid membrane transporter.

Regulation of NF-{kappa}B activity in astrocytes: effects of flavonoids at dietary-relevant concentrations

Energy Technology Data Exchange (ETDEWEB)

Spilsbury, Alison [Reading School of Pharmacy, University of Reading, Reading RG6 6UB (United Kingdom); Vauzour, David; Spencer, Jeremy P.E. [Molecular Nutrition Group, Centre for Integrative Neuroscience and Neurodynamics, School of Chemistry, Food and Pharmacy, University of Reading, Reading RG6 6AP (United Kingdom); Rattray, Marcus, E-mail: m.a.n.rattray@reading.ac.uk [Reading School of Pharmacy, University of Reading, Reading RG6 6UB (United Kingdom)

2012-02-17

Highlights: Black-Right-Pointing-Pointer We tested the hypothesis that low concentrations of flavonoids inhibit NF-{kappa}B in astrocytes. Black-Right-Pointing-Pointer Primary cultured astrocytes possess a functional {kappa}B-system, measured using luciferase assays. Black-Right-Pointing-Pointer Seven flavonoids (100 nM-1 {mu}M) failed to reduce NF-{kappa}B activity in astrocytes. Black-Right-Pointing-Pointer Four flavonoids (100 nM-1 {mu}M) failed to reduce TNFa-stimulated NF-{kappa}B activity in astrocytes. Black-Right-Pointing-Pointer (-)-Epicatechin did not regulate nuclear translocation of the NF-{kappa}B subunit, p65. -- Abstract: Neuroinflammation plays an important role in the progression of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Sustained activation of nuclear transcription factor {kappa}B (NF-{kappa}B) is thought to play an important role in the pathogenesis of neurodegenerative disorders. Flavonoids have been shown to possess antioxidant and anti-inflammatory properties and we investigated whether flavonoids, at submicromolar concentrations relevant to their bioavailability from the diet, were able to modulate NF-{kappa}B signalling in astrocytes. Using luciferase reporter assays, we found that tumour necrosis factor (TNF{alpha}, 150 ng/ml) increased NF-{kappa}B-mediated transcription in primary cultures of mouse cortical astrocytes, which was abolished on co-transfection of a dominant-negative I{kappa}B{alpha} construct. In addition, TNF{alpha} increased nuclear localisation of p65 as shown by immunocytochemistry. To investigate potential flavonoid modulation of NF-{kappa}B activity, astrocytes were treated with flavonoids from different classes; flavan-3-ols ((-)-epicatechin and (+)-catechin), flavones (luteolin and chrysin), a flavonol (kaempferol) or the flavanones (naringenin and hesperetin) at dietary-relevant concentrations (0.1-1 {mu}M) for 18 h. None of the flavonoids modulated constitutive or

Zinc oxide crystal whiskers as a novel sorbent for solid-phase extraction of flavonoids.

Science.gov (United States)

Wang, Licheng; Shangguan, Yangnan; Hou, Xiudan; Jia, Yong; Liu, Shujuan; Sun, Yingxin; Guo, Yong

2017-08-15

As a novel solid-phase extraction material, zinc oxide crystal whiskers were used to extract flavonoid compounds and showed good extraction abilities. X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy and surface area/pore volume characterized the sorbent. The zinc oxide was packed into a solid-phase extraction micro-column and its extraction ability was evaluated by four model flavonoid compounds. The sample loading and elution parameters were optimized and the zinc oxide based analytical method for flavonoids was established. It showed that the method has wide linearities from 1 to 150μg/L and low limits of detection at 0.25μg/L. The relative standard deviations of a single column repeatability and column to column reproducibility were less than 6.8% and 10.6%. Several real samples were analyzed by the established method and satisfactory results were obtained. The interactions between flavonoids and zinc oxide were calculated and proved to be from the Van der Waals' forces between the 4p and 5d orbitals from zinc atom and the neighboring π orbitals from flavonoid phenyl groups. Moreover, the zinc oxide crystal whiskers showed good stability and could be reused more than 50 times under the operation conditions. This work proves that the zinc oxide crystal whiskers are a good candidate for flavonoids enrichment. Copyright © 2017. Published by Elsevier B.V.

Concurrent synthesis and release of nod-gene-inducing flavonoids from alfalfa roots

International Nuclear Information System (INIS)

Maxwell, C.A.; Phillips, D.A.

1990-01-01

Flavonoid signals from alfalfa (Medicago sativa L.) induce transcription of nodulation (nod) genes in Rhizobium meliloti. Alfalfa roots release three major nod-gene inducers: 4',7-dihydroxyflavanone, 4',7-dihydroxyflavone, and 4,4'-dihydroxy-2'-methoxychalcone. The objective of the present study was to define temporal relationships between synthesis and exudation for those flavonoids. Requirements for concurrent flavonoid biosynthesis were assessed by treating roots of intact alfalfa seedlings with [U- 14 C]-L-phenylalanine in the presence or absence of the phenylalanine ammonia-lyase inhibitor L-2-aminoxy-3-phenylpropionic acid (AOPP). In the absence of AOPP, each of the three flavonoids in exudates contained 14 C. In the presence of AOPP, 14 C labeling and release of all the exuded nod-gene inducers were reduced significantly. AOPP inhibited labeling and release of the strongest nod-gene inducer, methoxychalcone, by more than 90%. The release process responsible for exudation of nod-gene inducers appears to be specific rather than a general phenomenon such as a sloughing off of cells during root growth

Detection of QTL for Carcass Quality on Chromosome 6 by Exploiting Linkage and Linkage Disequilibrium in Hanwoo

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J.-H. Lee

2012-01-01

Full Text Available The purpose of this study was to improve mapping power and resolution for the QTL influencing carcass quality in Hanwoo, which was previously detected on the bovine chromosome (BTA 6. A sample of 427 steers were chosen, which were the progeny from 45 Korean proven sires in the Hanwoo Improvement Center, Seosan, Korea. The samples were genotyped with the set of 2,535 SNPs on BTA6 that were imbedded in the Illumina bovine 50 k chip. A linkage disequilibrium variance component mapping (LDVCM method, which exploited both linkage between sires and their steers and population-wide linkage disequilibrium, was applied to detect QTL for four carcass quality traits. Fifteen QTL were detected at 0.1% comparison-wise level, for which five, three, five, and two QTL were associated with carcass weight (CWT, backfat thickness (BFT, longissimus dorsi muscle area (LMA, and marbling score (Marb, respectively. The number of QTL was greater compared with our previous results, in which twelve QTL for carcass quality were detected on the BTA6 in the same population by applying other linkage disequilibrium mapping approaches. One QTL for LMA was detected on the distal region (110,285,672 to 110,633,096 bp with the most significant evidence for linkage (p<10−5. Another QTL that was detected on the proximal region (33,596,515 to 33,897,434 bp was pleiotrophic, i.e. influencing CWT, BFT, and LMA. Our results suggest that the LDVCM is a good alternative method for QTL fine-mapping in detection and characterization of QTL.

A general model for likelihood computations of genetic marker data accounting for linkage, linkage disequilibrium, and mutations.

Science.gov (United States)

Kling, Daniel; Tillmar, Andreas; Egeland, Thore; Mostad, Petter

2015-09-01

Several applications necessitate an unbiased determination of relatedness, be it in linkage or association studies or in a forensic setting. An appropriate model to compute the joint probability of some genetic data for a set of persons given some hypothesis about the pedigree structure is then required. The increasing number of markers available through high-density SNP microarray typing and NGS technologies intensifies the demand, where using a large number of markers may lead to biased results due to strong dependencies between closely located loci, both within pedigrees (linkage) and in the population (allelic association or linkage disequilibrium (LD)). We present a new general model, based on a Markov chain for inheritance patterns and another Markov chain for founder allele patterns, the latter allowing us to account for LD. We also demonstrate a specific implementation for X chromosomal markers that allows for computation of likelihoods based on hypotheses of alleged relationships and genetic marker data. The algorithm can simultaneously account for linkage, LD, and mutations. We demonstrate its feasibility using simulated examples. The algorithm is implemented in the software FamLinkX, providing a user-friendly GUI for Windows systems (FamLinkX, as well as further usage instructions, is freely available at www.famlink.se ). Our software provides the necessary means to solve cases where no previous implementation exists. In addition, the software has the possibility to perform simulations in order to further study the impact of linkage and LD on computed likelihoods for an arbitrary set of markers.

An Association Map on the Effect of Flavonoids on the Signaling Pathways in Colorectal Cancer.

Science.gov (United States)

Koosha, Sanaz; Alshawsh, Mohammed A; Looi, Chung Yeng; Seyedan, Atefehalsadat; Mohamed, Zahurin

2016-01-01

Colorectal cancer (CRC) is the third most common type of cancer in the world, causing thousands of deaths annually. Although chemotherapy is known to be an effective treatment to combat colon cancer, it produces severe side effects. Natural products, on the other hand, appear to generate fewer side effects than do chemotherapeutic drugs. Flavonoids are polyphenolic compounds found in various fruits and vegetables known to possess antioxidant activities, and the literature shows that several of these flavonoids have anti-CRC propertiesFlavonoids are classified into five main subclasses: flavonols, flavanones, flavones, flavan-3-ols, and flavanonols. Of these subclasses, the flavanonols have a minimum effect against CRC, whereas the flavones play an important role. The main targets for the inhibitory effect of flavonoids on CRC signaling pathways are caspase; nuclear factor kappa B; mitogen-activated protein kinase/p38; matrix metalloproteinase (MMP)-2, MMP-7, and MMP-9; p53; β-catenin; cyclin-dependent kinase (CDK)2 and CDK4; and cyclins A, B, D, and E. In this review article, we summarize the in vitro and in vivo studies that have been performed since 2000 on the anti-CRC properties of flavonoids. We also describe the signaling pathways affected by flavonoids that have been found to be involved in CRC. Some flavonoids have the potential to be an effective alternative to chemotherapeutic drugs in the treatment of colon cancer; well-controlled clinical studies should, however, be conducted to support this proposal.

Novel biosensors based on flavonoid-responsive transcriptional regulators introduced into Escherichia coli

DEFF Research Database (Denmark)

Siedler, Solvej; Stahlhut, Steen Gustav; Malla, Sailesh

2014-01-01

This study describes the construction of two flavonoid biosensors, which can be applied for metabolic engineering of Escherichia coli strains. The biosensors are based on transcriptional regulators combined with autofluorescent proteins. The transcriptional activator FdeR from Herbaspirillum...... and externally added flavonoid concentration. The QdoR-biosensor was successfully applied for detection of kaempferol production in vivo at the single cell level by fluorescence-activated cell sorting. Furthermore, the amount of kaempferol produced highly correlated with the specific fluorescence of E. coli...... cells containing a flavonol synthase from Arabidopsis thaliana (fls1). We expect the designed biosensors to be applied for isolation of genes involved in flavonoid biosynthetic pathways. © 2013 The Authors....

Mapping of yield, yield stability, yield adaptability and other traits in barley using linkage disequilibrium mapping and linkage analysis

NARCIS (Netherlands)

Kraakman, A.T.W.

2005-01-01

Plants is mostly done through linkage analysis. A segregating mapping population Identification and mappping of Quantitative Trait Loci (QTLs) in is created from a bi-parental cross and linkages between trait values and mapped markers reveal the positions ofQTLs. In

Two-locus linkage analysis in multiple sclerosis (MS)

Energy Technology Data Exchange (ETDEWEB)

Tienari, P.J. (National Public Health Institute, Helsinki (Finland) Univ. of Helsinki (Finland)); Terwilliger, J.D.; Ott, J. (Columbia Univ., New York (United States)); Palo, J. (Univ. of Helsinki (Finland)); Peltonen, L. (National Public Health Institute, Helsinki (Finland))

1994-01-15

One of the major challenges in genetic linkage analyses is the study of complex diseases. The authors demonstrate here the use of two-locus linkage analysis in multiple sclerosis (MS), a multifactorial disease with a complex mode of inheritance. In a set of Finnish multiplex families, they have previously found evidence for linkage between MS susceptibility and two independent loci, the myelin basic protein gene (MBP) on chromosome 18 and the HLA complex on chromosome 6. This set of families provides a unique opportunity to perform linkage analysis conditional on two loci contributing to the disease. In the two-trait-locus/two-marker-locus analysis, the presence of another disease locus is parametrized and the analysis more appropriately treats information from the unaffected family member than single-disease-locus analysis. As exemplified here in MS, the two-locus analysis can be a powerful method for investigating susceptibility loci in complex traits, best suited for analysis of specific candidate genes, or for situations in which preliminary evidence for linkage already exists or is suggested. 41 refs., 6 tabs.

Isolation And Purification Of Flavonoids From The Leaves Of Locally Produced Carica Papaya

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Yahaya Mobmi Musa

2015-08-01

Full Text Available ABSTRACT The leaves of Carica papaya 150g was defatted with N-Hexane and extracted with Methanol. The N-Hexane exract showed the presence of Flavonoid Saponin Tannin Glycoside Anthraquinone Resin and Steroid while Methanolic extract showed the presence of Flavonoid Saponin and Resins. 6g of the Methanolic extract was chromatographed using Column chromatography over Silica gel of column 200g60-200 mesh and eluted with the solvent mixture of CH2Cl2CH3OH H2O in the ratio of 70301. The yield of the isolated Flavonoid was 0.23.

Separation and determination of flavonoids in three traditional chinese medicines by capillary electrophoresis with amperometric detection.

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Wang, Wei; Lin, Ping; Ma, Lihong; Xu, Kaixuan; Lin, Xiuli

2016-04-01

Flavonoids are important active ingredients in many traditional Chinese medicines. In this paper, capillary electrophoresis with amperometric detection was employed to separate and detect eight flavonoids, rutin, quercetrin, quercetin, kaempferol, kaempferide, catechin, apigenin, and luteolin, in a home-made capillary electrophoresis device. Under the separation voltage of 2000 V, the eight flavonoids could be completely separated within 33 min in 18 mM borax running buffer at pH 10.2. Good linear relationships were obtained for all analytes and the detection limits for flavonoids ranged from 0.46 to 0.85 μM. Then, the method was applied to separate and determine the flavonoids in three traditional Chinese medicines, hippophae rhamnoides, hypericum perforatum, and cacumen platycladi. Finally, rutin, kaempferol, quercetin, and quercetrin were discovered in these medicines and the concentrations ranged from 0.28 to 9.94 mg/g. The recoveries of flavonoids ranged from 84.7 to 113%, which showed the high reliability of this method. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pectolinarigenin - A Flavonoid Compound from Cirsium Japonicum ...

African Journals Online (AJOL)

HP

/tjpr.v13i2.9. Original Research Article. Pectolinarigenin - A Flavonoid Compound from Cirsium. Japonicum with Potential Anti-proliferation Activity in MCF-. 7 Breast Cancer Cell. Mingqian Lu. 1,2,3. , Qingzhi Kong. 1,4. *, Xinhua Xu. 2,3.

[Analysis of dynamic changes of flavonoids and alkaloids during different drying process of Morus alba leaves].

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Bai, Yong-liang; Duan, Jin-ao; Su, Shu-lan; Qian, Ye-fei; Qian, Da-wei; Ouyang, Zhen

2014-07-01

To find out dynamic changes of flavonoids and alkaloids in Morus alba leaves by analyzing influence of different drying method and drying degrees, in order to provide evidence for quality evaluation of Morus alba leaves. Different drying methods, programmed temperature methods and constant temperature methods were adopted to dry Morus alba leaves samples respectively. Contents of flavonoids and alkaloids were analyzed by HPLC-PDA and LC-TQ/MS respectively. It's shown obviously that the content of flavonoids were influenced heavily by different drying methods. Methods that suitable for flavonoids were freezing-dried > shade-dried > dried > sun-dried > microwave-dried > infrared-dried; Methods that suitable for alkaloids were freezing-dried > shade-dried > dried > sun-dried > infrared-dried > microwave-dried. The 55 -65 degrees C group was shown to be the lowest in both flavonoids and DNJ while the 85 - 95 degrees C group was shown to be the best for DNJ. For fagomine, the 45 degrees C group was shown to be the lowest concentrations while the 95 - 105 degrees C group was shown to be the highest. Samples with different moisture were shown to be different in content of flavonoids and alkaloids. And samples with 10% moisture contain highest flavonoids while those with 30% - 50% moisture contain lowest flavonoids. Content of DNJ and fagomine raised as moisture decreasing. In addition, the 55 - 65 degrees C group was better than the 95 -105 degrees C one in alkaloids content. The results provide optimal drying methods and condition for drying Morus alba leaves, and foundations for uncovering biochemical transform of Morus alba leaves.

Using Bureaucratic and Cultural Linkages to Improve Instruction: The Principal's Contribution.

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Firestone, William A.; Wilson, Bruce L.

1985-01-01

Principals can influence teachers and instructional behavior by working through linkage mechanisms within the organizational structure of the school. Two types of linkages are identified: bureaucratic and cultural. Principals have access to linkages of both kinds; using linkages effectively, they can generate a common purpose in their schools. (MD)

Flavonoids inhibit histamine release and expression of proinflammatory cytokines in mast cells.

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Park, Hyo-Hyun; Lee, Soyoung; Son, Hee-Young; Park, Seung-Bin; Kim, Mi-Sun; Choi, Eun-Ju; Singh, Thoudam S K; Ha, Jeoung-Hee; Lee, Maan-Gee; Kim, Jung-Eun; Hyun, Myung Chul; Kwon, Taeg Kyu; Kim, Yeo Hyang; Kim, Sang-Hyun

2008-10-01

Mast cells participate in allergy and inflammation by secreting inflammatory mediators such as histamine and proinflammatory cytokines. Flavonoids are naturally occurring molecules with antioxidant, cytoprotective, and antiinflammatory actions. However, effect of flavonoids on the release of histamine and proinflammatory mediator, and their comparative mechanism of action in mast cells were not well defined. Here, we compared the effect of six flavonoids (astragalin, fisetin, kaempferol, myricetin, quercetin, and rutin) on the mast cell-mediated allergic inflammation. Fisetin, kaempferol, myricetin, quercetin, and rutin inhibited IgE or phorbol-12-myristate 13-acetate and calcium ionophore A23187 (PMACI)-mediated histamine release in RBL-2H3 cells. These five flavonoids also inhibited elevation of intracellular calcium. Gene expressions and secretion of proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-6, and IL-8 were assessed in PMACI-stimulated human mast cells (HMC-1). Fisetin, quercetin, and rutin decreased gene expression and production of all the proinflammatory cytokines after PMACI stimulation. Myricetin attenuated TNF-alpha and IL-6 but not IL-1beta and IL-8. Fisetin, myricetin, and rutin suppressed activation of NF-kappaB indicated by inhibition of nuclear translocation of NF-kappaB, NF-kappaB/DNA binding, and NF-kappaB-dependent gene reporter assay. The pharmacological actions of these flavonoids suggest their potential activity for treatment of allergic inflammatory diseases through the down-regulation of mast cell activation.

Antioxidant activity, total phenols and flavonoids of lichens from Venezuelan Andes.

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Claudia M. Plaza

2014-10-01

Full Text Available Context:The biological potential of lichens has been documented through their use in traditional medicine. Secondary lichen metabolites exert a wide variety of biological actions, including their use as antioxidants. Aims:To evaluate the antioxidant activity, total phenol content, and flavonoids of four lichen fungal taxa collected in Mérida (Venezuela, and statistically evaluate the correlation between the antioxidant activity and the amount of phenols and flavonoids in the samples. Methods: Extracts were prepared with water, ethanol and dichloromethane from Cladonia aff. rappii, Cora aff. glabrata, Peltigera laciniata and Thamnolia vermicularis. The antioxidant capacity assessment was determined using DPPH• radical method and reducing power, with ascorbic acid as control. Total phenols were determined by means of the Folin-Ciocalteu method with gallic acid. Total flavonoids were estimated according to the modified Dowd method, using quercetin as standard. Results:The ethanolic extracts of the tested lichens showed the highest scavenging activity and reducing power compared to water and dichloromethane extracts at 4 mg/mL. The highest antiradical power value was found in ethanolic extract of Peltigera laciniata (2.28 mL/mgand the lowest in dichloromethane extract of Cora aff. glabrata (0.30 mL/mg. The correlation between antioxidant activity and total phenolic content was moderate. The flavonoids content of ethanolic extracts was highly significant but negative (p < 0.05. There was good correlation in dichloromethane extracts. The ethanolic extract of P. laciniata exhibited the highest antiradical activity despite showing the lowest flavonoid content. Conclusions: The ethanolic extracts of lichens tested showed to have the higher antioxidant activity and may be used as natural sources of new antioxidants.

Antimicrobial mechanism of flavonoids against Escherichia coli ATCC 25922 by model membrane study

International Nuclear Information System (INIS)

He, Mengying; Wu, Ting; Pan, Siyi; Xu, Xiaoyun

2014-01-01

Antimicrobial mechanism of four flavonoids (kaempferol, hesperitin, (+)-catechin hydrate, biochanin A) against Escherichia coli ATCC 25922 was investigated through cell membranes and a liposome model. The release of bacterial protein and images from transmission electron microscopy demonstrated damage to the E. coli ATCC 25922 membrane. A liposome model with dipalmitoylphosphatidylethanolamine (DPPE) (0.6 molar ratio) and dipalmitoylphosphatidylglycerol (DPPG) (0.4 molar ratio), representative of the phospholipid membrane of E. coli ATCC 25922, was used to specify the mode of action of four selected flavonoids through Raman spectroscopy and differential scanning calorimetry. It is suggested that for flavonoids, to be effective antimicrobials, interaction with the polar head-group of the model membrane followed by penetration into the hydrophobic regions must occur. The antimicrobial efficacies of the flavonoids were consistent with liposome interaction activities, kaempferol > hesperitin > (+)-catechin hydrate > biochanin A. This study provides a liposome model capable of mimicking the cell membrane of E. coli ATCC 25922. The findings are important in understanding the antibacterial mechanism on cell membranes.

Antimicrobial mechanism of flavonoids against Escherichia coli ATCC 25922 by model membrane study

Energy Technology Data Exchange (ETDEWEB)

He, Mengying; Wu, Ting; Pan, Siyi; Xu, Xiaoyun, E-mail: xiaoyunxu88@gmail.com

2014-06-01

Antimicrobial mechanism of four flavonoids (kaempferol, hesperitin, (+)-catechin hydrate, biochanin A) against Escherichia coli ATCC 25922 was investigated through cell membranes and a liposome model. The release of bacterial protein and images from transmission electron microscopy demonstrated damage to the E. coli ATCC 25922 membrane. A liposome model with dipalmitoylphosphatidylethanolamine (DPPE) (0.6 molar ratio) and dipalmitoylphosphatidylglycerol (DPPG) (0.4 molar ratio), representative of the phospholipid membrane of E. coli ATCC 25922, was used to specify the mode of action of four selected flavonoids through Raman spectroscopy and differential scanning calorimetry. It is suggested that for flavonoids, to be effective antimicrobials, interaction with the polar head-group of the model membrane followed by penetration into the hydrophobic regions must occur. The antimicrobial efficacies of the flavonoids were consistent with liposome interaction activities, kaempferol > hesperitin > (+)-catechin hydrate > biochanin A. This study provides a liposome model capable of mimicking the cell membrane of E. coli ATCC 25922. The findings are important in understanding the antibacterial mechanism on cell membranes.

Flavonoids and Reduction of Cardiovascular Disease (CVD) in Chronic Obstructive Pulmonary Disease (COPD).

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Russo, Patrizia; Prinzi, Giulia; Lamonaca, Palma; Cardaci, Vittorio; Fini, Massimo

2018-05-13

Chronic obstructive pulmonary disease (COPD) and cardiovascular diseases (CV) often coexist. COPD and CVD are complex diseases characterized by a strict interaction between environment and genetic. The mechanisms linking these two diseases are complex, multifactorial and not entirely understood, influencing the therapeutic approach. COPD is characterized by several comorbidities, it is hypothesizable that treatment of cardiovascular co-morbidities may reduce morbidity and mortality. Flavonoids are an important class of plant low molecular weight secondary metabolites (SMs). Convincing data from laboratory, epidemiological, and human clinical studies point to an important effects on CVD risk prevention. This review aims to provide up-to-date information on the ability of Flavonoids to reduce the CVD risk. Current studies support the potential of Flavonoids to prevent the risk of CVD. Well-designed clinical studies are suggested to evaluate advantages and limits of Flavonoids for managing CVD comorbidity in COPD. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

[Study on antioxidant activity of flavonoids from leaves of Psidium guajava].

Science.gov (United States)

Zhao, Yu-Jing; Li, Jian-Kuan; Zhang, Xin; Gao, Jian-Ping

2018-02-01

The present study is to study the chemical constituents from ethanol extract of Psidium guajava leaves. The constituents were separated and purified by silica gel column chromaiographios over, macroporous resin D-101, Sephadex LH-20, and ODS. Six flavonoids compounds were isolated and identified as quercetin(1), quercetin-3- O - α -D-arabinopyranoside(2), quercetin-3- O - α -D-ribopyranoside(3), quercetin-3- O - β -D-galactopyranoside(4), quercetin-3- O - α -D-glucopyranoside(5), and quercetin-3- O - α- D-xylpyranoside(6). The antioxidant effects of six flavonoids was evaluated by scavenging ability of DPPH, superoxide anion, ABTS·⁺, and reducing effect of Fe³⁺ as well as total antioxidant capacity(FRAP). Vitamin C was used as positive control. The results indicated that six flavonoids exhibited significant antioxidant effects. Copyright© by the Chinese Pharmaceutical Association.

Flavonoid intake from food and beverages: What We Eat in America, NHANES 2007-2008, Tables 1-4

Science.gov (United States)

The Food Surveys Research Group of the Beltsville Human Nutrition Research Center has released 4 flavonoid intake data tables that make available, for the first time, nationally representative estimates of the intake of 29 individual flavonoids in six classes (as well as the sum of those flavonoids)...

FUNCTIONAL SPECIALIZATION OF DUPLICATED FLAVONOID BIOSYNTHESIS GENES IN WHEAT

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Khlestkina E.

2012-08-01

Full Text Available Gene duplication followed by subfunctionalization and neofunctionalization is of a great evolutionary importance. In plant genomes, duplicated genes may result from either polyploidization (homoeologous genes or segmental chromosome duplications (paralogous genes. In allohexaploid wheat Triticum aestivum L. (2n=6x=42, genome BBAADD, both homoeologous and paralogous copies were found for the regulatory gene Myc encoding MYC-like transcriptional factor in the biosynthesis of flavonoid pigments, anthocyanins, and for the structural gene F3h encoding one of the key enzymes of flavonoid biosynthesis, flavanone 3-hydroxylase. From the 5 copies (3 homoeologous and 2 paralogous of the Myc gene found in T. aestivum, only one plays a regulatory role in anthocyanin biosynthesis, interacting complementary with another transcriptional factor (MYB-like to confer purple pigmentation of grain pericarp in wheat. The role and functionality of the other 4 copies of the Myc gene remain unknown. From the 4 functional copies of the F3h gene in T. aestivum, three homoeologues have similar function. They are expressed in wheat organs colored with anthocyanins or in the endosperm, participating there in biosynthesis of uncolored flavonoid substances. The fourth copy (the B-genomic paralogue is transcribed neither in wheat organs colored with anthocyanins nor in seeds, however, it’s expression has been noticed in roots of aluminium-stressed plants, where the three homoeologous copies are not active. Functional diversification of the duplicated flavonoid biosynthesis genes in wheat may be a reason for maintenance of the duplicated copies and preventing them from pseudogenization.The study was supported by RFBR (11-04-92707. We also thank Ms. Galina Generalova for technical assistance.

Citrus Flavonoid Supplementation Improves Exercise Performance in Trained Athletes

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Elvera Overdevest, Jeroen A. Wouters, Kevin H.M. Wolfs, Job J.M. van Leeuwen, Sam Possemiers

2018-03-01

Full Text Available Previous studies have shown that polyphenol supplementation may be an effective strategy to improve exercise performance, due to their antioxidant character and ability to stimulate NO production. These properties may contribute to exercise performance, yet no conclusive research has been performed in exploring the direct effects of citrus flavonoids on human exercise performance. Therefore, the purpose of this study was to assess whether supplementation of a customized citrus flavonoid (CF extract for 4 weeks improves cycling time-trial performance in trained male athletes. In a double-blind, randomized, parallel study, 39 healthy, trained males were given a daily dose of either 500 mg of a customized citrus flavonoid extract (CF or a placebo for 4 weeks. Exercise performance was tested by means of a time-trial test on a cycle ergometer, during which participants had to generate as much power as possible for duration of 10 minutes. Absolute power output significantly increased with 14.9 ± 3.9 W after 4 weeks of CF supplementation, corresponding with a 5.0% increase, compared to 3.8 ± 3.2 W (1.3% increase in placebo (p < 0.05. In addition, oxygen consumption/power ratio significantly decreased in the CF group compared to placebo (p = 0.001, and a trend was found in the change in peak power output in CF (18.2 ± 23.2 W versus placebo (-28.4 ± 17.6 W; p = 0.116. The current study is the first convincing report that citrus flavonoid supplementation can improve exercise performance, as shown by a significant increase in power output during the exercise test.

Identification of a flavonoid C-glycoside as potent antioxidant.

Science.gov (United States)

Wen, Lingrong; Zhao, Yupeng; Jiang, Yueming; Yu, Limei; Zeng, Xiaofang; Yang, Jiali; Tian, Miaomiao; Liu, Huiling; Yang, Bao

2017-09-01

Flavonoids have been documented to have good antioxidant activities in vitro. However, reports on the cellular antioxidant activities of flavonoid C-glycosides are very limited. In this work, an apigenin C-glycoside was purified from Artocarpus heterophyllus by column chromatography and was identified to be 2″-O-β-D-xylosylvitexin by nuclear magnetic resonance spectroscopy. The cellular antioxidant activity and anticancer activity of 2″-O-β-D-xylosylvitexin were evaluated for the first time. The quantitative structure-activity relationship was analysed by molecular modeling. Apigenin presented an unexpected cellular antioxidation behaviour. It had an antioxidant activity at low concentration and a prooxidant activity at high concentration, whereas 2″-O-β-D-xylosylvitexin showed a dose-dependent cellular antioxidant activity. It indicated that C-glycosidation improved the cellular antioxidation performance of apigenin and eliminated the prooxidant effect. The ortho-dihydroxyl at C-3'/C-4' and C-3 hydroxyl in the flavonoid skeleton play important roles in the antioxidation behaviour. The cell proliferation assay revealed a low cytotoxicity of 2″-O-β-D-xylosylvitexin. Copyright © 2017 Elsevier Inc. All rights reserved.

Complexation of Flavonoids with Iron: Structure and Optical Signatures

Science.gov (United States)

Ren, Jun; Meng, Sheng; Lekka, Ch. E.; Kaxiras, Efthimios

2008-03-01

Flavonoids exhibit antioxidant behavior believed to be related to their metal ion chelation ability. We investigate the complexation mechanism of several flavonoids, quercetin, luteolin, galangin, kaempferol and chrysin with iron, the most abundant type of metal ions in the body, through first- principles electronic structure calculations based on Density Functional Theory (DFT). We find that the most likely chelation site for Fe is the 3-hydroxyl-4-carbonyl group, followed by 4- carbonyl-5-hydroxyl group and the 3'-4' hydroxyl (if present) for all the flavonoid molecules studied. Three quercetin molecules are required to saturate the bonds of a single Fe ion by forming six orthogonal Fe-O bonds, though the binding energy per molecule is highest for complexes consisting of two quercetin molecules and one Fe atom, in agreement with experiment. Optical absorption spectra calculated with time- dependent DFT serve as signatures to identify various complexes. For the iron-quercetin complexes, we find a redshift of the first absorbance peak upon complexation in good agreement with experiment; this behavior is explained by the narrowing of the optical gap of quercetin due to Fe(d)--O(p) orbital hybridization.

Seasonal variation of flavonoids in Teucrium polium L. (Lamiaceae

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Gjoshe Stefkov

2009-02-01

Full Text Available Тhe aim of the present study was identification of flavone aglycones and determination of the content of each and the content of total flavonoids as well as investigation of the eventual seasonal variations of flavonoids in Teucrium polium L. (Lamiaceae. The plant samples were collected at six different locations in Republic of Macedonia, during summer in 1999, 2000 and 2003. For determination of seasonal variations, the samples were collected in v. Koleshino, in 2004, each month during the whole season. Six flavone aglycones (luteolin, apigenin, diosmetin, cirsiliol, cirsimaritin and cirsilineol were identified in the hydrolyzed extracts of the over ground part of Teucrium polium by HPLC method. The most abundant flavone was luteolin, followed by apigenin and cirsimaritin. Great seasonal variations were found in the content of each and in the content of total amount of flavonoids. The most abundant flavone during the whole season was luteolin with the highest content in May. The content of total flavonids was the highest in the period from May to July, which could be recommended as the most convenience period in the season for collecting of the plant material from Teucrium polium.

Systematic Exploration of Natural and Synthetic Flavonoids for the Inhibition of Staphylococcus aureus Biofilms

Science.gov (United States)

Manner, Suvi; Skogman, Malena; Goeres, Darla; Vuorela, Pia; Fallarero, Adyary

2013-01-01

When single-cell (or suspended) bacteria switch into the biofilm lifestyle, they become less susceptible to antimicrobials, imposing the need for anti-biofilms research. Flavonoids are among the most extensively studied natural compounds with an unprecedented amount of bioactivity claims. Most studies focus on the antibacterial effects against suspended cells; fewer reports have researched their anti-biofilm properties. Here, a high throughput phenotypic platform was utilized to screen for the inhibitory activity of 500 flavonoids, including natural and synthetic derivatives, against Staphylococcus aureus biofilms. Since discrepancies among results from earlier antibacterial studies on flavonoids had been noted, the current study aimed to minimize sources of variations. After the first screen, flavonoids were classified as inactive (443), moderately active (47) or highly active (10). Further, exclusion criteria combining bioactivity and selectivity identified two synthetic flavans as the most promising. The body of data reported here serves three main purposes. First, it offers an improved methodological workflow for anti-biofilm screens of chemical libraries taking into account the (many times ignored) connections between anti-biofilm and antibacterial properties. This is particularly relevant for the study of flavonoids and other natural products. Second, it provides a large and freely available anti-biofilm bioactivity dataset that expands the knowledge on flavonoids and paves the way for future structure-activity relationship studies and structural optimizations. Finally, it identifies two new flavans that can successfully act on biofilms, as well as on suspended bacteria and represent more feasible antibacterial candidates. PMID:24071942

Mechanism of inhibition of human secretory phospholipase A2 by flavonoids: rationale for lead design

Science.gov (United States)

Lättig, Jens; Böhl, Markus; Fischer, Petra; Tischer, Sandra; Tietböhl, Claudia; Menschikowski, Mario; Gutzeit, Herwig O.; Metz, Peter; Pisabarro, M. Teresa

2007-08-01

The human secretory phospholipase A2 group IIA (PLA2-IIA) is a lipolytic enzyme. Its inhibition leads to a decrease in eicosanoids levels and, thereby, to reduced inflammation. Therefore, PLA2-IIA is of high pharmacological interest in treatment of chronic diseases such as asthma and rheumatoid arthritis. Quercetin and naringenin, amongst other flavonoids, are known for their anti-inflammatory activity by modulation of enzymes of the arachidonic acid cascade. However, the mechanism by which flavonoids inhibit Phospholipase A2 (PLA2) remained unclear so far. Flavonoids are widely produced in plant tissues and, thereby, suitable targets for pharmaceutical extractions and chemical syntheses. Our work focuses on understanding the binding modes of flavonoids to PLA2, their inhibition mechanism and the rationale to modify them to obtain potent and specific inhibitors. Our computational and experimental studies focused on a set of 24 compounds including natural flavonoids and naringenin-based derivatives. Experimental results on PLA2-inhibition showed good inhibitory activity for quercetin, kaempferol, and galangin, but relatively poor for naringenin. Several naringenin derivatives were synthesized and tested for affinity and inhibitory activity improvement. 6-(1,1-dimethylallyl)naringenin revealed comparable PLA2 inhibition to quercetin-like compounds. We characterized the binding mode of these compounds and the determinants for their affinity, selectivity, and inhibitory potency. Based on our results, we suggest C(6) as the most promising position of the flavonoid scaffold to introduce chemical modifications to improve affinity, selectivity, and inhibition of PLA2-IIA by flavonoids.

Distribution of lod scores in oligogenic linkage analysis.

Science.gov (United States)

Williams, J T; North, K E; Martin, L J; Comuzzie, A G; Göring, H H; Blangero, J

2001-01-01

In variance component oligogenic linkage analysis it can happen that the residual additive genetic variance bounds to zero when estimating the effect of the ith quantitative trait locus. Using quantitative trait Q1 from the Genetic Analysis Workshop 12 simulated general population data, we compare the observed lod scores from oligogenic linkage analysis with the empirical lod score distribution under a null model of no linkage. We find that zero residual additive genetic variance in the null model alters the usual distribution of the likelihood-ratio statistic.

Investigation of three flavonoids binding to bovine serum albumin using molecular fluorescence technique

International Nuclear Information System (INIS)

Bi Shuyun; Yan Lili; Pang Bo; Wang Yu

2012-01-01

The three flavonoids including naringenin, hesperetin and apigenin binding to bovine serum albumin (BSA) at pH 7.4 was studied by fluorescence quenching, synchronous fluorescence and UV-vis absorption spectroscopic techniques. The results obtained revealed that naringenin, hesperetin and apigenin strongly quenched the intrinsic fluorescence of BSA. The Stern-Volmer curves suggested that these quenching processes were all static quenching processes. At 291 K, the value and the order of the binding constant were K A n aringenin) =4.08x10 4 A(hesperetin) =5.40x10 4 ∼K A(apigenin) =5.32x10 4 L mol -1 . The main binding force between the flavonoid and BSA was hydrophobic and electrostatic force. According to the Foerster theory of non-radiation energy transfer, the binding distances (r 0 ) were obtained as 3.36, 3.47 and 3.30 nm for naringenin-BSA, hesperetin-BSA and apigenin-BSA, respectively. The effect of some common ions such as Fe 3+ , Cu 2+ , Mg 2+ , Mn 2+ , Zn 2+ and Ca 2+ on the binding was also studied in detail. The competition binding was also performed. The apparent binding constant (K' A ) obtained suggested that one flavonoid had an obvious effect on the binding of another flavonoid to protein when they coexisted in BSA solution. - Highlights: → Quenchings of BSA fluorescence by the flavonoids was all static quenchings. → Synchronous fluorescence was applied to study the structural change of BSA. → Binding constant, binding site and binding force were determined. → Competition binding experiments were performed. → One flavonoid had an obvious effect on the binding of another one to BSA.

Recent advances and trends in the liquid-chromatography-mass spectrometry analysis of flavonoids.

Science.gov (United States)

de Villiers, André; Venter, Pieter; Pasch, Harald

2016-01-22

Flavonoids have elicited significant attention as a result of their importance in plants, their influence on the properties of natural-product derived commodities and especially as a consequence of their purported health benefits. Research in all of these fields relies heavily on accurate analytical data, and in this LC-MS has come to play an influential role by allowing relatively fast tentative identification and accurate quantification of low levels of flavonoids in a variety of matrices. The field has undergone rapid expansion in the last decade due to important developments in both HPLC and MS instrumentation, which nowadays allow much faster and more accurate analysis of flavonoids. This contribution aims to provide an overview of these developments and their application in flavonoid analysis since 2009. The discussion is focussed first on methodologies which provide improved LC separation of flavonoids in terms of speed and/or resolution, including ultra high pressure LC (UHPLC), monolithic and superficially porous phases, high temperature LC (HTLC) and comprehensive two-dimensional LC (LC×LC). The fundamental background relevant to each of these will be briefly outlined, as well as the implications and promise of their hyphenation to MS. Secondly, the possibilities and limitations of a range of the latest MS instruments available in combination with advanced LC analysis will be discussed, including ion trap, triple quadrupole, time-of-flight, Orbitrap, ion mobility and various hybrid instruments. Examples from the latest literature will be used to illustrate the performance gains achievable in flavonoid analysis by the hyphenation of advanced LC separation and high-end MS instrumentation. Copyright © 2015 Elsevier B.V. All rights reserved.

Data Linkage: A powerful research tool with potential problems

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Scott Ian

2010-12-01

Full Text Available Abstract Background Policy makers, clinicians and researchers are demonstrating increasing interest in using data linked from multiple sources to support measurement of clinical performance and patient health outcomes. However, the utility of data linkage may be compromised by sub-optimal or incomplete linkage, leading to systematic bias. In this study, we synthesize the evidence identifying participant or population characteristics that can influence the validity and completeness of data linkage and may be associated with systematic bias in reported outcomes. Methods A narrative review, using structured search methods was undertaken. Key words "data linkage" and Mesh term "medical record linkage" were applied to Medline, EMBASE and CINAHL databases between 1991 and 2007. Abstract inclusion criteria were; the article attempted an empirical evaluation of methodological issues relating to data linkage and reported on patient characteristics, the study design included analysis of matched versus unmatched records, and the report was in English. Included articles were grouped thematically according to patient characteristics that were compared between matched and unmatched records. Results The search identified 1810 articles of which 33 (1.8% met inclusion criteria. There was marked heterogeneity in study methods and factors investigated. Characteristics that were unevenly distributed among matched and unmatched records were; age (72% of studies, sex (50% of studies, race (64% of studies, geographical/hospital site (93% of studies, socio-economic status (82% of studies and health status (72% of studies. Conclusion A number of relevant patient or population factors may be associated with incomplete data linkage resulting in systematic bias in reported clinical outcomes. Readers should consider these factors in interpreting the reported results of data linkage studies.

Chemopreventive Potential of Flavonoids in Oral Squamous Cell Carcinoma in Human Studies

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Elena Maria Varoni

2013-07-01

Full Text Available Evidence available from nutritional epidemiology has indicated an inverse association between regular consumption of fruits and vegetables and the risk of developing certain types of cancer. In turn, preclinical studies have attributed the health-promoting effects of plant foods to some groups of phytochemicals, by virtue of their many biological activities. In this survey, we briefly examine the chemopreventive potential of flavonoids and flavonoid-rich foods in human oral carcinogenesis. Despite the paucity of data from clinical trials and epidemiological studies, in comparison to in vitro/in vivo investigations, a high level of evidence has been reported for epigallocatechin gallate (EGCG and anthocyanins. These flavonoids, abundant in green tea and black raspberries, respectively, represent promising chemopreventive agents in human oral cancer.

Flavonoids and Phenolic Acids from Oregano: Occurrence, Biological Activity and Health Benefits.

Science.gov (United States)

Gutiérrez-Grijalva, Erick P; Picos-Salas, Manuel A; Leyva-López, Nayely; Criollo-Mendoza, Marilyn S; Vazquez-Olivo, Gabriela; Heredia, J Basilio

2017-12-26

Several herb species classified as oregano have been widely used in folk medicine to alleviate inflammation-related diseases, respiratory and digestive disorders, headaches, rheumatism, diabetes and others. These potential health benefits are partially attributed to the phytochemical compounds in oregano such as flavonoids (FL) and phenolic acids (PA). Flavonoids and phenolic acids are among the most abundant and most studied phytochemicals in oregano species. Epidemiological, in vitro and in vivo experiments have related long-term consumption of dietary FL and PA with a decreased risk of incidence of chronic diseases. The aim of this manuscript is to summarize the latest studies on the identification and distribution of flavonoids and phenolic compounds from oregano species and their potential antioxidant, anti-inflammatory and anti-cancer health benefits.

Flavonoids and a neolignan glucoside from Guarea macrophylla (Meliaceae)

International Nuclear Information System (INIS)

Pereira, Cristiane; Barreto Junior, Cleber Bomfim; Kuster, Ricardo Machado; Simas, Naomi Kato; Sakuragui, Cassia Monica; Porzel, Andrea; Wessjohann, Ludger

2012-01-01

This work describes the phytochemical study of the methanol extract obtained from leaves of Guarea macrophylla, leading to the isolation and identification of three flavonoid glycosides (quercetin 3-O-β-D-glucopyranoside, quercetin 3-O-b-D-galactopyranoside, kaempferol 7-O-β-D-glucopyranoside) and a neolignan glucoside, dehydrodiconiferyl alcohol-4-b-D-glucoside. All compounds were identified by a combination of spectroscopic methods ( 1 H, 1D, 2D NMR, 13 C and UV), ESI-MS and comparison with the literature data. This is the first report of flavonoids in the genus Guarea and of a neolignan glucoside in the Meliaceae family. (author)

Triterpenes and flavonoids from the roots of Mauritia flexuosa

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Hector H. F. Koolen

2011-11-01

Full Text Available Mauritia flexuosa L. f., Arecaceae, is an endemic species of South America. This species was studied with the intent to isolate the constituents of its roots. After the fractionation of the n-hexane and methanolic extracts from the roots of M. flexuosa, six triterpenes were obtained: friedelin, taraxerone, lupenyl acetate, lupenone, betulin and betulinic acid, along with three flavonoids: rutin, quercitrin and quercetin. All the compounds were identified by analysis of NMR and MS data and comparison with the literature. All those compounds are been reported for the first time in Mauritia, and the chemosystematic significance of the flavonoids isolated in this genus is discussed.

Triterpenes and flavonoids from the roots of Mauritia flexuosa

Directory of Open Access Journals (Sweden)

Hector H. F. Koolen

2012-02-01

Full Text Available Mauritia flexuosa L. f., Arecaceae, is an endemic species of South America. This species was studied with the intent to isolate the constituents of its roots. After the fractionation of the n-hexane and methanolic extracts from the roots of M. flexuosa, six triterpenes were obtained: friedelin, taraxerone, lupenyl acetate, lupenone, betulin and betulinic acid, along with three flavonoids: rutin, quercitrin and quercetin. All the compounds were identified by analysis of NMR and MS data and comparison with the literature. All those compounds are been reported for the first time in Mauritia, and the chemosystematic significance of the flavonoids isolated in this genus is discussed.

Flavonoids and a neolignan glucoside from Guarea macrophylla (Meliaceae

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Cristiane Pereira

2012-01-01

Full Text Available This work describes the phytochemical study of the methanol extract obtained from leaves of Guarea macrophylla, leading to the isolation and identification of three flavonoid glycosides (quercetin 3-O-β-D-glucopyranoside, quercetin 3-O-b-D-galactopyranoside, kaempferol 7-O-β-D-glucopyranoside and a neolignan glucoside, dehydrodiconiferyl alcohol-4-β-D-glucoside. All compounds were identified by a combination of spectroscopic methods (¹H, 1D, 2D NMR, 13C and UV, ESI-MS and comparison with the literature data. This is the first report of flavonoids in the genus Guarea and of a neolignan glucoside in the Meliaceae family.

Differential effects of dietary flavonoids on drug metabolizing and antioxidant enzymes in female rat

DEFF Research Database (Denmark)

Breinholt, V.; Lauridsen, S.T.; Dragsted, L.O.

1999-01-01

1. Gavage administration of the natural flavonoids tangeretin, chrysin, apigenin, naringenin, genistein and quercetin for 2 consecutive weeks to the female rat resulted in differential effects on selected phase 1 and 2 enzymes in liver, colon and heart as well as antioxidant enzymes in red brood......) significantly protected against, 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP)-induced oxidative stress. Hepatic PhIP-DNA adduct formation was not affected by any of the administered flavonoids, whereas PhIP-DNA adduct formation in colon was slightly, but significantly, inhibited by quercetin......, genistein, tangeretin and BNF. 5. The observed effects of chrysin, quercetin and genistein on antioxidant enzymes, concurrently with a protection against oxidative stress, suggest a feedback mechanism on the antioxidant enzymes triggered by the flavonoid antioxidants. 6. Despite the use of high flavonoid...

Quercetin - A Flavonoid Compound from Sarcopyramis bodinieri var ...

African Journals Online (AJOL)

The flavonoid compound was identified as quercetin by 1H-. NMR and ESI-MS ... phenolic compounds were isolated, and their .... scored under a fluorescence microscope (Carl. Zeiss .... Antioxidant Properties of Sarcopyramis bodinieri.

An iterative glycosyltransferase EntS catalyzes transfer and extension of O- and S-linked monosaccharide in enterocin 96.

Science.gov (United States)

Nagar, Rupa; Rao, Alka

2017-05-12

Glycosyltransferases are essential tools for in vitro-glycoengineering. Bacteria harbor an unexplored variety of protein glycosyltransferases. Here, we describe a peptide glycosyltransferase (EntS) encoded by ORF0417 of Enterococcus faecalis TX0104. EntS di-glycosylates linear peptide of enterocin 96- a known antibacterial, in vitro. It is capable of transferring as well as extending the glycan onto the peptide in an iterative sequential dissociative manner. It can catalyze multiple linkages: Glc/Gal(-O)Ser/Thr, Glc/Gal(-S)Cys and Glc/Gal(β)Glc/Gal(-O/S)Ser/Thr/Cys, in one pot. Using EntS generated glycovariants of enterocin 96 peptide, size and identity of the glycan are found to influence bioactivity of the peptide. The study identifies EntS as an enzyme worth pursuing, for in vitro peptide glycoengineering. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Genome-wide linkage scan for colorectal cancer susceptibility genes supports linkage to chromosome 3q

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Velculescu Victor E

2008-04-01

Full Text Available Abstract Background Colorectal cancer is one of the most common causes of cancer-related mortality. The disease is clinically and genetically heterogeneous though a strong hereditary component has been identified. However, only a small proportion of the inherited susceptibility can be ascribed to dominant syndromes, such as Hereditary Non-Polyposis Colorectal Cancer (HNPCC or Familial Adenomatous Polyposis (FAP. In an attempt to identify novel colorectal cancer predisposing genes, we have performed a genome-wide linkage analysis in 30 Swedish non-FAP/non-HNPCC families with a strong family history of colorectal cancer. Methods Statistical analysis was performed using multipoint parametric and nonparametric linkage. Results Parametric analysis under the assumption of locus homogeneity excluded any common susceptibility regions harbouring a predisposing gene for colorectal cancer. However, several loci on chromosomes 2q, 3q, 6q, and 7q with suggestive linkage were detected in the parametric analysis under the assumption of locus heterogeneity as well as in the nonparametric analysis. Among these loci, the locus on chromosome 3q21.1-q26.2 was the most consistent finding providing positive results in both parametric and nonparametric analyses Heterogeneity LOD score (HLOD = 1.90, alpha = 0.45, Non-Parametric LOD score (NPL = 2.1. Conclusion The strongest evidence of linkage was seen for the region on chromosome 3. Interestingly, the same region has recently been reported as the most significant finding in a genome-wide analysis performed with SNP arrays; thus our results independently support the finding on chromosome 3q.

Isolation and identification of flavonoids from anticancer and ...

African Journals Online (AJOL)

Isolation and identification of flavonoids from anticancer and neuroprotective extracts of Trigonella foenum graecum. Shabina Ishtiaq Ahmed, Muhammad Qasim Hayat, Saadia Zahid, Muhammad Tahir, Qaisar Mansoor, Muhammad Ismail, Kristen Keck, Robert Bates ...

Antimicrobial and antioxidant properties of the flavonoid extract from Raphanus sativus L.

Science.gov (United States)

Ngoc, Pham Thi Kim; Nguyet, Nguyen Thi Minh; Dao, Dong Thi Anh

2017-09-01

This study was conducted to evaluate the in vitro antimicrobial and antioxidant activities of flavonoid extract from white radish roots (Raphanus sativus L.). Antimicrobial activity was determined by agar diffusion method against 4 strains: Bacillus cereus, Staphylococus aureus, Pseudomonas aeruginosa and Salmonella typhi. Antioxidant activity was determined by ABTS* radical scavenging activity and total antioxidant capacity (TAC). The constituent elements of flavonoid extract were identified by LC-MS. Results showed that the flavonoid extract from Raphanus sativus L. had antibacterial activity against to all four tested bacteria strains with antibacterial ring diameters in the range 8 - 20 mm in the test concentrations from 100 to 1600 mg/ml. Minimum concentration to inhibit (MIC) in the range 20 - 40 mg/ml. In addition, the extract also has the ability to eliminate ABTS* free radical with IC50 = 7.074 µg/ml. The total antioxidant capacity of extract at concentration of 100 µg/ml was 3.424 ± 0.043 mg ascorbic acid/mg. In the extract, there are three flavonoids were found: rutin, quercetin and narigenin. This is the first time narigenin was found in Raphanus sativus L. extract.

SERS-Based Flavonoid Detection Using Ethylenediamine-β-Cyclodextrin as a Capturing Ligand

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Jae Min Choi

2017-01-01

Full Text Available Ethylenediamine-modified β-cyclodextrin (Et-β-CD was immobilized on aggregated silver nanoparticle (NP-embedded silica NPs (SiO2@Ag@Et-β-CD NPs for the effective detection of flavonoids. Silica NPs were used as the template for embedding silver NPs to create hot spots and enhance surface-enhanced Raman scattering (SERS signals. Et-β-CD was immobilized on Ag NPs to capture flavonoids via host-guest inclusion complex formation, as indicated by enhanced ultraviolet absorption spectra. The resulting SiO2@Ag@Et-β-CD NPs were used as the SERS substrate for detecting flavonoids, such as hesperetin, naringenin, quercetin, and luteolin. In particular, luteolin was detected more strongly in the linear range 10−7 to 10−3 M than various organic molecules, namely ethylene glycol, β-estradiol, isopropyl alcohol, naphthalene, and toluene. In addition, the SERS signal for luteolin captured by the SiO2@Ag@Et-β-CD NPs remained even after repeated washing. These results indicated that the SiO2@Ag@Et-β-CD NPs can be used as a rapid, sensitive, and selective sensor for flavonoids.

Flavonoids Suppress Pseudomonas aeruginosa Virulence through Allosteric Inhibition of Quorum-sensing Receptors*

Science.gov (United States)

Paczkowski, Jon E.; Mukherjee, Sampriti; McCready, Amelia R.; Cong, Jian-Ping; Aquino, Christopher J.; Kim, Hahn; Henke, Brad R.; Smith, Chari D.; Bassler, Bonnie L.

2017-01-01

Quorum sensing is a process of cell-cell communication that bacteria use to regulate collective behaviors. Quorum sensing depends on the production, detection, and group-wide response to extracellular signal molecules called autoinducers. In many bacterial species, quorum sensing controls virulence factor production. Thus, disrupting quorum sensing is considered a promising strategy to combat bacterial pathogenicity. Several members of a family of naturally produced plant metabolites called flavonoids inhibit Pseudomonas aeruginosa biofilm formation by an unknown mechanism. Here, we explore this family of molecules further, and we demonstrate that flavonoids specifically inhibit quorum sensing via antagonism of the autoinducer-binding receptors, LasR and RhlR. Structure-activity relationship analyses demonstrate that the presence of two hydroxyl moieties in the flavone A-ring backbone are essential for potent inhibition of LasR/RhlR. Biochemical analyses reveal that the flavonoids function non-competitively to prevent LasR/RhlR DNA binding. Administration of the flavonoids to P. aeruginosa alters transcription of quorum sensing-controlled target promoters and suppresses virulence factor production, confirming their potential as anti-infectives that do not function by traditional bacteriocidal or bacteriostatic mechanisms. PMID:28119451

Molecular Mechanisms of the Anti-Obesity and Anti-Diabetic Properties of Flavonoids.

Science.gov (United States)

Kawser Hossain, Mohammed; Abdal Dayem, Ahmed; Han, Jihae; Yin, Yingfu; Kim, Kyeongseok; Kumar Saha, Subbroto; Yang, Gwang-Mo; Choi, Hye Yeon; Cho, Ssang-Goo

2016-04-15

Obesity and diabetes are the most prevailing health concerns worldwide and their incidence is increasing at a high rate, resulting in enormous social costs. Obesity is a complex disease commonly accompanied by insulin resistance and increases in oxidative stress and inflammatory marker expression, leading to augmented fat mass in the body. Diabetes mellitus (DM) is a metabolic disorder characterized by the destruction of pancreatic β cells or diminished insulin secretion and action insulin. Obesity causes the development of metabolic disorders such as DM, hypertension, cardiovascular diseases, and inflammation-based pathologies. Flavonoids are the secondary metabolites of plants and have 15-carbon skeleton structures containing two phenyl rings and a heterocyclic ring. More than 5000 naturally occurring flavonoids have been reported from various plants and have been found to possess many beneficial effects with advantages over chemical treatments. A number of studies have demonstrated the potential health benefits of natural flavonoids in treating obesity and DM, and show increased bioavailability and action on multiple molecular targets. This review summarizes the current progress in our understanding of the anti-obesity and anti-diabetic potential of natural flavonoids and their molecular mechanisms for preventing and/or treating obesity and diabetes.

An estimating function approach to linkage heterogeneity

Indian Academy of Sciences (India)

Testing linkage heterogeneity between two loci is an important issue in genetics. Currently, there are ... on linkage heterogeneity can help people to better understand complex .... χ2(F − 2) + cχ2 (1), where c is a constant (see Appendix). Here, it can be ..... gin, ancestry, gender, age, etc., for purpose of dividing sub- groups to ...

Bayesian linkage and segregation analysis: factoring the problem.

Science.gov (United States)

Matthysse, S

2000-01-01

Complex segregation analysis and linkage methods are mathematical techniques for the genetic dissection of complex diseases. They are used to delineate complex modes of familial transmission and to localize putative disease susceptibility loci to specific chromosomal locations. The computational problem of Bayesian linkage and segregation analysis is one of integration in high-dimensional spaces. In this paper, three available techniques for Bayesian linkage and segregation analysis are discussed: Markov Chain Monte Carlo (MCMC), importance sampling, and exact calculation. The contribution of each to the overall integration will be explicitly discussed.

Mobile assemblies of Bennett linkages from four-crease origami patterns

Science.gov (United States)

Zhang, Xiao; Chen, Yan

2018-02-01

This paper deals with constructing mobile assemblies of Bennett linkages inspired by four-crease origami patterns. A transition technique has been proposed by taking the thick-panel form of an origami pattern as an intermediate bridge. A zero-thickness rigid origami pattern and its thick-panel form share the same sector angles and folding behaviours, while the thick-panel origami and the mobile assembly of linkages are kinematically equivalent with differences only in link profiles. Applying this transition technique to typical four-crease origami patterns, we have found that the Miura-ori and graded Miura-ori patterns lead to assemblies of Bennett linkages with identical link lengths. The supplementary-type origami patterns with different mountain-valley crease assignments correspond to different types of Bennett linkage assemblies with negative link lengths. And the identical linkage-type origami pattern generates a new mobile assembly. Hence, the transition technique offers a novel approach to constructing mobile assemblies of spatial linkages from origami patterns.

Activity of flavonoids through λ sub max and electron cross-section

International Nuclear Information System (INIS)

Murthy, V.R.; Sreenivasulu, M.

1997-01-01

Flavonoids are widespread groups of natural constituents and present in the drugs in the form of mono or diglycosides. Being physiologically active, flavonoids are important in the field of pharmacological and clinical applications. Not many physical properties of flavonoids have been studied so far excepting UV and NMR studies. This paper deals with the evaluation of electron ionization cross section through λ sub max, a parameter available from UV studies. Electron ionization cross section was primarily conceived to be of use in radiation chemical data, mass spectroscopic and thermodynamic studies. But later attempts to correlate electron ionization cross-section with structural and related parameters prompted the authors to derive an explicit expression relating λ sub max and electron ionization cross-section (Q). The application of this method to correlate Q through λ sub max and interpret the results in terms of chemical activity are discussed

Molecular mechanisms of flavonoids in melanin synthesis and the potential for the prevention and treatment of melanoma.

Science.gov (United States)

Liu-Smith, Feng; Meyskens, Frank L

2016-06-01

Flavonoids are becoming popular nutraceuticals. Different flavonoids show similar or distinct biological effects on different tissues or cell types, which may limit or define their usefulness in cancer prevention and/or treatment application. This review focuses on a few selected flavonoids and discusses their functions in normal and transformed pigment cells, including cyanidin, apigenin, genistein, fisetin, EGCG, luteolin, baicalein, quercetin and kaempferol. Flavonoids exhibit melanogenic or anti-melanogenic effects mainly via transcriptional factor MiTF and/or the melanogenesis enzymes tyrosinase, DCT or TYRP-1. To identify a direct target has been a challenge as most studies were not able to discriminate whether the effect(s) of the flavonoid were from direct targeting or represented indirect effects. Flavonoids exhibit an anti-melanoma effect via inhibiting cell proliferation and invasion and inducing apoptosis. The mechanisms are also multi-fold, via ROS-scavenging, immune-modulation, cell cycle regulation and epigenetic modification including DNA methylation and histone deacetylation. In summary, although many flavonoid compounds are extremely promising nutraceuticals, their detailed molecular mechanism and their multi-target (simultaneously targeting multiple molecules) nature warrant further investigation before advancement to translational studies or clinical trials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antioxidant Capacity of Flavonoids in Hepatic Microsomes Is not Reflected by Antioxidant Effects In Vivo

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Garry Duthie

2012-01-01

Full Text Available Flavonoids are polyphenolic compounds with potential antioxidant activity via multiple reduction capacities. Oxidation of cellular lipids has been implicated in many diseases. Consequently, this study has assessed the ability of several dietary flavonoid aglycones to suppress lipid peroxidation of hepatic microsomes derived from rats deficient in the major lipid soluble antioxidant, dα-tocopherol. Antioxidant effectiveness was galangin > quercetin > kaempferol > fisetin > myricetin > morin > catechin > apigenin. However, none of the flavonoids were as effective as dα-tocopherol, particularly at the lowest concentrations used. In addition, there appears to be an important distinction between the in vitro antioxidant effectiveness of flavonoids and their ability to suppress indices of oxidation in vivo. Compared with dα-tocopherol, repletion of vitamin E deficient rats with quercetin, kaempferol, or myricetin did not significantly affect indices of lipid peroxidation and tissue damage. Direct antioxidant effect of flavonoids in vivo was not apparent probably due to low bioavailability although indirect redox effects through stimulation of the antioxidant response element cannot be excluded.

Flavonoids in vegetable foods commonly consumed in Brazil and estimated ingestion by the Brazilian population.

Science.gov (United States)

Arabbi, Paola R; Genovese, Maria Inés; Lajolo, Franco M

2004-03-10

The objective of this work was to quantify the flavonoids present in foods most commonly consumed by the Brazilian population. The predominant flavonoids found in largest abundance in all of the analyzed vegetables were glycosides of quercetin. In lettuce, a small amount of luteolin was also detected. In sweet pepper, quercetin and luteolin were both present. White onion [48-56 mg/100 g of fresh weight (FW), expressed as aglycon], red onion (40-100 mg/100 g of FW), red lettuce (67-67.2 mg/100 g of FW), arugula (41-118 mg/100 g of FW), and chicory (18-38 mg/100 g of FW) were highest in total flavonoids. In fruits, the highest concentrations of flavonoids were found in the peel (125-170 mg/100 g of FW) and pulp (35-44 mg/100 g of FW) of oranges and in some apple varieties (14-36 mg/100 g of FW). Variability in flavonoid content due to time of harvesting was high for leafy vegetables and red onions. The estimated ingestion by Brazilian population ranged from 60 to 106 mg/day.

Beneficial Effects of Different Flavonoids on Vascular and Renal Function in L-NAME Hypertensive Rats

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M. Dolores Paredes

2018-04-01

Full Text Available Background: we have evaluated the antihypertensive effect of several flavonoid extracts in a rat model of arterial hypertension caused by chronic administration (6 weeks of the nitric oxide synthesis inhibitor, L-NAME. Methods: Sprague Dawley rats received L-NAME alone or L-NAME plus flavonoid-rich vegetal extracts (Lemon, Grapefruit + Bitter Orange, and Cocoa or purified flavonoids (Apigenin and Diosmin for 6 weeks. Results: L-NAME treatment resulted in a marked elevation of blood pressure, and treatment with Apigenin, Lemon Extract, and Grapefruit + Bitter Orange extracts significantly reduced the elevated blood pressure of these animals. Apigenin and some of these flavonoids also ameliorated nitric oxide-dependent and -independent aortic vasodilation and elevated nitrite urinary excretion. End-organ abnormalities such as cardiac infarcts, hyaline arteriopathy and fibrinoid necrosis in coronary arteries and aorta were improved by these treatments, reducing the end-organ vascular damage. Conclusions: the flavonoids included in this study, specially apigenin, may be used as functional food ingredients with potential therapeutic benefit in arterial hypertension.

A Review of the Cognitive Effects Observed in Humans Following Acute Supplementation with Flavonoids, and Their Associated Mechanisms of Action

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Lynne Bell

2015-12-01

Full Text Available Flavonoids are polyphenolic compounds found in varying concentrations in many plant-based foods. Recent studies suggest that flavonoids can be beneficial to both cognitive and physiological health. Long term flavonoid supplementation over a period of weeks or months has been extensively investigated and reviewed, particularly with respect to cognitive ageing and neurodegenerative disease. Significantly less focus has been directed towards the short term effects of single doses of flavonoids on cognition. Here, we review 21 such studies with particular emphasis on the subclass and dose of flavonoids administered, the cognitive domains affected by flavonoid supplementation, and the effect size of the response. The emerging evidence suggests that flavonoids may be beneficial to attention, working memory, and psychomotor processing speed in a general population. Episodic memory effects are less well defined and may be restricted to child or older adult populations. The evidence also points towards a dose-dependent effect of flavonoids, but the physiological mechanisms of action remain unclear. Overall, there is encouraging evidence that flavonoid supplementation can benefit cognitive outcomes within an acute time frame of 0–6 h. But larger studies, combining cognitive and physiological measures, are needed to strengthen the evidence base.

Dimensional threshold for fracture linkage and hooking

Science.gov (United States)

Lamarche, Juliette; Chabani, Arezki; Gauthier, Bertrand D. M.

2018-03-01

Fracture connectivity in rocks depends on spatial properties of the pattern including length, abundance and orientation. When fractures form a single-strike set, they hardly cross-cut each other and the connectivity is limited. Linkage probability increases with increasing fracture abundance and length as small fractures connect to each other to form longer ones. A process for parallel fracture linkage is the "hooking", where two converging fracture tips mutually deviate and then converge to connect due to the interaction of their crack-tip stresses. Quantifying the processes and conditions for fracture linkage in single-strike fracture sets is crucial to better predicting fluid flow in Naturally Fractured Reservoirs. For 1734 fractures in Permian shales of the Lodève Basin, SE France, we measured geometrical parameters in 2D, characterizing three stages of the hooking process: underlapping, overlapping and linkage. We deciphered the threshold values, shape ratios and limiting conditions to switch from one stage to another one. The hook set up depends on the spacing (S) and fracture length (Lh) with the relation S ≈ 0.15 Lh. Once the hooking is initiated, with the fracture deviation length (L) L ≈ 0.4 Lh, the fractures reaches the linkage stage only when the spacing is reduced to S ≈ 0.02 Lh and the convergence (C) is < 0.1 L. These conditions apply to multi-scale fractures with a shape ratio L/S = 10 and for fracture curvature of 10°-20°.

Systematic chemical analysis approach reveals superior antioxidant capacity via the synergistic effect of flavonoid compounds in red vegetative tissues

Science.gov (United States)

Qin, Xiaoxiao; Lu, Yanfen; Peng, Zhen; Fan, Shuangxi; Yao, Yuncong

2018-02-01

The flavonoid system comprises an abundance of compounds with multiple functions; however, their potential synergism in antioxidant function remains unclear. We established an approach using ever-red (RL) and ever-green leaves (GL) of crabapple cultivars during their development to determine interrelationships among flavonoid compounds. RL scored significantly better than GL in terms of the type, composition, and diversity of flavonoids than GL. Principal component analysis predicted flavonoids in RL to have positive interaction effects, and the total antioxidant capacity was significantly higher than the sum of antioxidant capacities of the individual compounds. This synergy was verified by the high antioxidant capacity in rat serum after feeding on red leaves. Our findings suggest that the synergistic effect is a result of the high transcription levels regulated by McMYBs in RL. In summary, individual flavonoids cooperate in a flavonoid system, thus producing a synergistic antioxidant effect, and the approach used herein can provide insights into the roles of flavonoids and other compounds in future studies.

Urinary metabolite profiling of flavonoids in Chinese volunteers after consumption of orange juice by UFLC-Q-TOF-MS/MS.

Science.gov (United States)

Zeng, Xuan; Su, Weiwei; Bai, Yang; Chen, Taobin; Yan, Zenghao; Wang, Jiawei; Su, Minmin; Zheng, Yuying; Peng, Wei; Yao, Hongliang

2017-09-01

The metabolism of flavonoids derived from orange juice in Chinese volunteers has not been well investigated. With the ultra-fast liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry (UFLC-Q-TOF-MS/MS) system, orange juice-derived flavonoids, as well as metabolites contained in urine collected from healthy Chinese volunteers after consumption of 250mL orange juice, were systematically identified and quantified. Finally, a total of 9 flavonoids and 30 metabolites were detected. Obtained results revealed that flavonoids derived from orange juice underwent extensive phase II metabolism in human, mainly comprising glucuronidation and sulfation. The overall recovery of the primary flavonoid aglycones, i.e., naringenin and hesperetin, were both approximately equivalent 22% of intake, primarily occurred in 4-12h post consumption. Meanwhile, additional 35 phenolic catabolites were identified in urine collected post consumption. However, it is difficult to determine the exact amounts of phenolic catabolites derived from specific flavonoid due to the interference of diets and other flavonoids. This work would be valuable for the clarification of metabolic profiles for flavonoids in Chinese population. Copyright © 2017 Elsevier B.V. All rights reserved.

Inhibitory effects of flavonoids on biofilm formation by Staphylococcus aureus that overexpresses efflux protein genes.

Science.gov (United States)

Lopes, Laênia Angélica Andrade; Dos Santos Rodrigues, Jéssica Bezerra; Magnani, Marciane; de Souza, Evandro Leite; de Siqueira-Júnior, José P

2017-06-01

This study evaluated the efficacy of glycone (myricitrin, hesperidin and phloridzin) and aglycone flavonoids (myricetin, hesperetin and phloretin) in inhibiting biofilm formation by Staphylococcus aureus RN4220 and S. aureus SA1199B that overexpress the msrA and norA efflux protein genes, respectively. The minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC 50 - defined as the lowest concentration that resulted in ≥50% inhibition of biofilm formation) of flavonoids were determined using microdilution in broth procedures. The flavonoids showed MIC >1024 μg/mL against S. aureus RN4220 and S. aureus SA1199B; however, these compounds at lower concentrations (1-256 μg/mL) showed inhibitory effects on biofilm formation by these strains. Aglycone flavonoids showed lower MBIC 50 values than their respective glycone forms. The lowest MBIC 50 values (1 and 4 μg/mL) were observed against S. aureus RN4220. Myricetin, hesperetin and phloretin exhibited biofilm formation inhibition >70% for S. aureus RN4220, and lower biofilm formation inhibition against S. aureus SA1199B. These results indicate that sub-MICs of the tested flavonoids inhibit biofilm formation by S. aureus strains that overexpress efflux protein genes. These effects are more strongly established by aglycone flavonoids. Copyright © 2017 Elsevier Ltd. All rights reserved.

Protection of free-radical induced DNA strand breaks in vitro by flavonoids

International Nuclear Information System (INIS)

Fisher, L.; Anderson, R.F.

1998-01-01

Full text: We have used both plasmid and cosmid test systems to assay the effect of antioxidant flavonoids (AO) on DNA strand breakage in supercoiled closed circular DNA (DNA SC ) following the formation oxidative radical damage on DNA (DNA OXID + . ) in aqueous solution. Single strand breaks in DNA SC result in the formation of the relaxed circular form (DNA RC ) and double strand breaks give linear DNA (DNA L ). Dose response curves were constructed for the log of the loss of [DNA S C] against dose (0-600 Gy). The D 37 (dose for 37% unchanged DNA SC ) values determined in the presence of increasing amounts of flavonoids were compared as ratios to the D 37 control value to give dose modification factor (DMF). Irradiations were carried out under 'constant scavenging' conditions to separate out the effect of direct radical scavenging from the possible electron transfer reaction. Control irradiation experiments, were performed in aerated TRIS buffer, concentration 10 mM, which has a scavenging capacity, k s (defined as the summation of the rate constants for the reaction of OH radicals with all species in solution, multiplied by their concentrations) of 1.5 x 10 7 s -1 . The concentration of TRIS was reduced upon addition of AO to maintain k s at this level. Data will be presented for examples from all four major types of flavonoids (flavonols, isoflavones, flavones and flavon-3-ols) showing DMF values plateau at near 2.0 even at low concentrations (ca. 20 μM) of the flavonoids. Increased DNA strand breaks following post irradiation incubation with endo III protein was unaffected by having the flavonoids present at the time of irradiation. This result suggests that the protection afforded by the flavonoids is unlikely to be in repairing radical damage on pyrimidine bases that are precursors of DNA strand breaks. Overall these studies provide evidence for an additional mechanism of antioxidant activity

Mapping of yield, yield stability, yield adaptability and other traits in barley using linkage disequilibrium mapping and linkage analysis

OpenAIRE

Kraakman, A.T.W.

2005-01-01

Plants is mostly done through linkage analysis. A segregating mapping population Identification and mappping of Quantitative Trait Loci (QTLs) in is created from a bi-parental cross and linkages between trait values and mapped markers reveal the positions ofQTLs. Inthisstudyweexploredlinkagedisequilibrium(LD)mappingof traits in a set of modernbarleycultivars. LDbetweenmolecularmarkerswasfoundup to a distance of 10 centimorgan,whichislargecomparedtootherspecies.Thelarge distancemightbeinducedb...

Effects and Mechanisms of Total Flavonoids from Blumea balsamifera (L. DC. on Skin Wound in Rats

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Yuxin Pang

2017-12-01

Full Text Available Chinese herbal medicine (CHM evolved through thousands of years of practice and was popular not only among the Chinese population, but also most countries in the world. Blumea balsamifera (L. DC. as a traditional treatment for wound healing in Li Nationality Medicine has a long history of nearly 2000 years. This study was to evaluate the effects of total flavonoids from Blumea balsamifera (L. DC. on skin excisional wound on the back of Sprague-Dawley rats, reveal its chemical constitution, and postulate its action mechanism. The rats were divided into five groups and the model groups were treated with 30% glycerol, the positive control groups with Jing Wan Hong (JWH ointment, and three treatment groups with high dose (2.52 g·kg−1, medium dose (1.26 g·kg−1, and low dose (0.63 g·kg−1 of total flavonoids from B. balsamifera. During 10 consecutive days of treatment, the therapeutic effects of rates were evaluated. On day 1, day 3, day 5, day 7, and day 10 after treatment, skin samples were taken from all the rats for further study. Significant increases of granulation tissue, fibroblast, and capillary vessel proliferation were observed at day 7 in the high dose and positive control groups, compared with the model group, with the method of 4% paraformaldehyde for histopathological examination and immunofluorescence staining. To reveal the action mechanisms of total flavonoids on wound healing, the levels of CD68, vascular endothelial growth factor (VEGF, transforming growth factor-β1 (TGF-β1, and hydroxyproline were measured at different days. Results showed that total flavonoids had significant effects on rat skin excisional wound healing compared with controls, especially high dose ones (p < 0.05. Furthermore, the total flavonoid extract was investigated phytochemically, and twenty-seven compounds were identified from the total flavonoid sample by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass

Subcritical ethanol extraction of flavonoids from Moringa oleifera leaf and evaluation of antioxidant activity.

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Wang, Yongqiang; Gao, Yujie; Ding, Hui; Liu, Shejiang; Han, Xu; Gui, Jianzhou; Liu, Dan

2017-03-01

A large-scale process to extract flavonoids from Moringa oleifera leaf by subcritical ethanol was developed and HPLC-MS analysis was conducted to qualitatively identify the compounds in the extracts. To optimize the effects of process parameters on the yield of flavonoids, a Box-Behnken design combined with response surface methodology was conducted in the present work. The results indicated that the highest extraction yield of flavonoids by subcritical ethanol extraction could reach 2.60% using 70% ethanol at 126.6°C for 2.05h extraction. Under the optimized conditions, flavonoids yield was substantially improved by 26.7% compared with the traditional ethanol reflux method while the extraction time was only 2h, and obvious energy saving was observed. FRAP and DPPH assays showed that the extracts had strong antioxidant and free radical scavenging activities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Record linkage for pharmacoepidemiological studies in cancer patients.

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Herk-Sukel, Myrthe P P van; Lemmens, Valery E P P; Poll-Franse, Lonneke V van de; Herings, Ron M C; Coebergh, Jan Willem W

2012-01-01

An increasing need has developed for the post-approval surveillance of (new) anti-cancer drugs by means of pharmacoepidemiology and outcomes research in the area of oncology. To create an overview that makes researchers aware of the available database linkages in Northern America and Europe which facilitate pharmacoepidemiology and outcomes research in cancer patients. In addition to our own database, i.e. the Eindhoven Cancer Registry (ECR) linked to the PHARMO Record Linkage System, we considered database linkages between a population-based cancer registry and an administrative healthcare database that at least contains information on drug use and offers a longitudinal perspective on healthcare utilization. Eligible database linkages were limited to those that had been used in multiple published articles in English language included in Pubmed. The HMO Cancer Research Network (CRN) in the US was excluded from this review, as an overview of the linked databases participating in the CRN is already provided elsewhere. Researchers who had worked with the data resources included in our review were contacted for additional information and verification of the data presented in the overview. The following database linkages were included: the Surveillance, Epidemiology, and End-Results-Medicare; cancer registry data linked to Medicaid; Canadian cancer registries linked to population-based drug databases; the Scottish cancer registry linked to the Tayside drug dispensing data; linked databases in the Nordic Countries of Europe: Norway, Sweden, Finland and Denmark; and the ECR-PHARMO linkage in the Netherlands. Descriptives of the included database linkages comprise population size, generalizability of the population, year of first data availability, contents of the cancer registry, contents of the administrative healthcare database, the possibility to select a cancer-free control cohort, and linkage to other healthcare databases. The linked databases offer a longitudinal

A guide to evaluating linkage quality for the analysis of linked data.

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Harron, Katie L; Doidge, James C; Knight, Hannah E; Gilbert, Ruth E; Goldstein, Harvey; Cromwell, David A; van der Meulen, Jan H

2017-10-01

Linked datasets are an important resource for epidemiological and clinical studies, but linkage error can lead to biased results. For data security reasons, linkage of personal identifiers is often performed by a third party, making it difficult for researchers to assess the quality of the linked dataset in the context of specific research questions. This is compounded by a lack of guidance on how to determine the potential impact of linkage error. We describe how linkage quality can be evaluated and provide widely applicable guidance for both data providers and researchers. Using an illustrative example of a linked dataset of maternal and baby hospital records, we demonstrate three approaches for evaluating linkage quality: applying the linkage algorithm to a subset of gold standard data to quantify linkage error; comparing characteristics of linked and unlinked data to identify potential sources of bias; and evaluating the sensitivity of results to changes in the linkage procedure. These approaches can inform our understanding of the potential impact of linkage error and provide an opportunity to select the most appropriate linkage procedure for a specific analysis. Evaluating linkage quality in this way will improve the quality and transparency of epidemiological and clinical research using linked data. © The Author 2017. Published by Oxford University Press on behalf of the International Epidemiological Association.

Chemoprevention of skin cancer by the flavonoid fraction of Saraca asoka.

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Cibin, T R; Devi, D Gayathri; Abraham, Annie

2010-05-01

Saraca asoka (Family - Caesalpiniaceae) has been widely used in the Ayurvedic (traditional Indian) system of medicine especially due to its wound healing property. The present study investigated the chemopreventive property of flavonoids from the flowers of Saraca asoka on 7,12 dimethyl benz(a)anthracene (DMBA) induced skin cancer in mice models. A single topical application of DMBA (100 microg/50 microL of acetone) followed after 2 weeks by three times a week treatment with croton oil (1% in acetone), for 20 weeks resulted in tumor induction. The topical application of the flavonoid fraction of S. asoka (FF S. asoka), 30 min prior to the application of croton oil thrice weekly for 20 weeks, caused a significant reduction in the number of tumors per mouse and the percentage of tumor-bearing mice. Also the latency period for the appearance of the first tumor was delayed by S. asoka pretreatment. In the flavonoid fraction (5 mg and 10 mg/kg body weight) treated animals, the levels of biochemical markers - rhodanese, myeloperoxidase, beta-D-glucuronidase, sialic acid, hexokinase and caspase 3 were significantly restored to near normal levels. These findings suggest the chemopreventive activity of flavonoids from S. asoka on two stage skin carcinogenesis. Histological data also support the chemopreventive potential of S. asoka. Copyright (c) 2009 John Wiley & Sons, Ltd.

Ultraviolet-B (UV-B) radiation as an elicitor of flavonoid production in callus cultures of jatropha (Jatropha curcas L.)

International Nuclear Information System (INIS)

Alvero-Bascos, E.M.; Ungson, L.B.

2012-01-01

Callus cultures of jatropha (Jatropha curcas L.) grown in Murashige and Skoog's (MS) medium supplemented with naphthalene-acetic acid (NAA, 20 microM) and 6-furfurylaminopurine (kinetin, 20 microM) were exposed to ultraviolet-B (UV-B) radiation to investigate its potential as an abiotic elicitor of flavonoid production. Prior to irradiation, the levels of the flavonoids, apigenin, vitexin and isovitexin in the leaf and callus extracts were determined through high performance liquid chromatography (HPLC). Results showed that vitexin and isovitexin were the dominant flavonoids in the leaves while only apigenin was detected in the calli, suggesting a correlation between the degree of differentiation and biosynthesis of flavonoids in plant tissues. Irradiation of callus cultures for 7 d using two UV-B doses (12.6 and 25.3 kJ/sq m) induced synthesis of all three flavonoids (up to 780 micro g/g dw increase) to levels similar to or higher than those found in whole leaves. The combined levels of the three flavonoids in the cultures treated with the higher UV-B dose were 20-fold higher than the control and were comparable to concentrations found in leaves while a 10-fold increase in combined flavonoid levels was observed in calli irradiated with the lower UV-B dose. Furthermore, random amplified polymorphic DNA (RAPD) analyses of DNA extracts from the leaves and calli revealed that UV-B irradiation enhanced flavonoid synthesis without altering DNA sequence. These results further support the supposed involvement of UV-B in the transcriptional regulation of the expression of flavonoid biosysnthetic genes. Overall, the findings showed that elicitation through UV-B irradiation is an effective strategy to induce flavonoid production in dedifferentiated J. curcas cultures that have lost their capacity to produce the flavonoids normally synthesized in intact organs. (author)

Flavonoid, hesperidine, total phenolic contents and antioxidant ...

African Journals Online (AJOL)

Additionally, the antioxidant activities were also determined by ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity. C. hystrix had the highest flavonoid and total phenolic contents while C. aurantifolia had the highest hesperidine content. The antioxidant activity of ...

Agriculture–Tourism Linkages in Botswana: Evidence from the ...

African Journals Online (AJOL)

Tourism researchers are increasingly recognising that strengthened linkages between the sectors of tourism and agriculture are significant for maximising local multipliers and especially for pro-poor impacts. This article examines the linkages between the tourism and agriculture sectors in Botswana using evidence ...

Flavonoids and Phenolic Acids from Oregano: Occurrence, Biological Activity and Health Benefits

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Erick P. Gutiérrez-Grijalva

2017-12-01

Full Text Available Several herb species classified as oregano have been widely used in folk medicine to alleviate inflammation-related diseases, respiratory and digestive disorders, headaches, rheumatism, diabetes and others. These potential health benefits are partially attributed to the phytochemical compounds in oregano such as flavonoids (FL and phenolic acids (PA. Flavonoids and phenolic acids are among the most abundant and most studied phytochemicals in oregano species. Epidemiological, in vitro and in vivo experiments have related long-term consumption of dietary FL and PA with a decreased risk of incidence of chronic diseases. The aim of this manuscript is to summarize the latest studies on the identification and distribution of flavonoids and phenolic compounds from oregano species and their potential antioxidant, anti-inflammatory and anti-cancer health benefits.

Autophagy as a Molecular Target of Flavonoids Underlying their Protective Effects in Human Disease.

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Prieto-Domínguez, Nestor; Garcia-Mediavilla, Maria V; Sanchez-Campos, Sonia; Mauriz, Jose L; Gonzalez-Gallego, Javier

2018-01-01

Autophagy is a cellular pathway with the ability to maintain cell homeostasis through the elimination of damaged or useless cellular components, and its deregulation may initiate or aggravate different human diseases. Flavonoids, a group of plant metabolites, are able to modulate different molecular and cellular processes including autophagy. To review the effects of flavonoids on autophagy pathway in both invasive and noninvasive human diseases, focusing on the global outcomes in their progression. Moreover, the efficacy of the combination of flavonoids with drugs or other natural nontoxic compounds was also reviewed. A literature search was performed to identify and analyze peer-reviewed publications containing in vitro and in vivo studies focused on autophagy deregulation in different proliferative and non-proliferative pathologies and the potential protective effects of flavonoids. Analyzed publications indicated that imbalance between cell death and survival induced by changes in autophagy play an important role in the pathophysiology of a number of human diseases. The use of different flavonoids as autophagy modulators, alone or in combination with other molecules, might be a worthy strategy in the treatment of cancer, neurodegenerative disorders, cardiovascular diseases, hepatic diseases, leishmaniasis, influenza, gastric ulcers produced by Helicobacter pylori infection, diabetes, asthma, age-related macular degeneration or osteoporosis. Flavonoids could potentially constitute important adjuvant agents of conventional therapies in the treatment of autophagy deregulation-related diseases. Moreover, combined therapy may help to diminish the doses of those conventional treatments, leading to reduced drug-derivative side effects and to improved patients' survival. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Effects of Flavonoid-rich Plant Extracts on Ruminal Methanogenesis, Microbial Populations and Fermentation Characteristics

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Eun T. Kim

2015-04-01

Full Text Available The objective of this study was to evaluate the in vitro effects of flavonoid-rich plant extracts (PE on ruminal fermentation characteristics and methane emission by studying their effectiveness for methanogenesis in the rumen. A fistulated Holstein cow was used as a donor of rumen fluid. The PE (Punica granatum, Betula schmidtii, Ginkgo biloba, Camellia japonica, and Cudrania tricuspidata known to have high concentrations of flavonoid were added to an in vitro fermentation incubated with rumen fluid. Total gas production and microbial growth with all PE was higher than that of the control at 24 h incubation, while the methane emission was significantly lower (p<0.05 than that of the control. The decrease in methane accumulation relative to the control was 47.6%, 39.6%, 46.7%, 47.9%, and 48.8% for Punica, Betula, Ginkgo, Camellia, and Cudrania treatments, respectively. Ciliate populations were reduced by more than 60% in flavonoid-rich PE treatments. The Fibrobacter succinogenes diversity in all added flavonoid-rich PE was shown to increase, while the Ruminoccocus albus and R. flavefaciens populations in all PE decreased as compared with the control. In particular, the F. succinogenes community with the addition of Birch extract increased to a greater extent than that of others. In conclusion, the results of this study showed that flavonoid-rich PE decreased ruminal methane emission without adversely affecting ruminal fermentation characteristics in vitro in 24 h incubation time, suggesting that the flavonoid-rich PE have potential possibility as bio-active regulator for ruminants.

Glycoform-Selective Prion Formation in Sporadic and Familial Forms of Prion Disease

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Xiao, Xiangzhu; Yuan, Jue; Haïk, Stéphane; Cali, Ignazio; Zhan, Yian; Moudjou, Mohammed; Li, Baiya; Laplanche, Jean-Louis; Laude, Hubert; Langeveld, Jan; Gambetti, Pierluigi; Kitamoto, Tetsuyuki; Kong, Qingzhong; Brandel, Jean-Philippe; Cobb, Brian A.; Petersen, Robert B.; Zou, Wen-Quan

2013-01-01

The four glycoforms of the cellular prion protein (PrPC) variably glycosylated at the two N-linked glycosylation sites are converted into their pathological forms (PrPSc) in most cases of sporadic prion diseases. However, a prominent molecular characteristic of PrPSc in the recently identified variably protease-sensitive prionopathy (VPSPr) is the absence of a diglycosylated form, also notable in familial Creutzfeldt-Jakob disease (fCJD), which is linked to mutations in PrP either from Val to Ile at residue 180 (fCJDV180I) or from Thr to Ala at residue 183 (fCJDT183A). Here we report that fCJDV180I, but not fCJDT183A, exhibits a proteinase K (PK)-resistant PrP (PrPres) that is markedly similar to that observed in VPSPr, which exhibits a five-step ladder-like electrophoretic profile, a molecular hallmark of VPSPr. Remarkably, the absence of the diglycosylated PrPres species in both fCJDV180I and VPSPr is likewise attributable to the absence of PrPres glycosylated at the first N-linked glycosylation site at residue 181, as in fCJDT183A. In contrast to fCJDT183A, both VPSPr and fCJDV180I exhibit glycosylation at residue 181 on di- and monoglycosylated (mono181) PrP prior to PK-treatment. Furthermore, PrPV180I with a typical glycoform profile from cultured cells generates detectable PrPres that also contains the diglycosylated PrP in addition to mono- and unglycosylated forms upon PK-treatment. Taken together, our current in vivo and in vitro studies indicate that sporadic VPSPr and familial CJDV180I share a unique glycoform-selective prion formation pathway in which the conversion of diglycosylated and mono181 PrPC to PrPSc is inhibited, probably by a dominant-negative effect, or by other co-factors. PMID:23527023

HPLC/DAD/MS analysis of flavonoids and cynamoyl derivatives in Vernonia amygdalina leaves

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Salawu, S O [Department of Biochemistry, Federal University of Technology, Akure (Nigeria); [Department of Pharmaceutical Science, University of Florence, Florence (Italy); [Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)], E-mail: sosalawu@yahoo.com; it, ssalawu@ictp trieste; Akindahunsi, A A [Department of Biochemistry, Federal University of Technology, Akure (Nigeria); Mulinacci, N; Giaccherini, C; Innocenti, M; Vincieri, F F [Department of Pharmaceutical Science, University of Florence, Florence (Italy)

2007-12-15

Flavonoids and cynamoyl derivatives occurring in Vernonia amygdalina leaves have been identified and quantified. The identified flavonoids were luteolin, luteolin 7-O-glucuronoside, luteolin 7-O-glucoside and other two rutinosides of luteolin, with the sugar moiety linked in 4' and 7' The main flavonoids are luteolin- 7-O-glucoside and luteolin- 7-O-glucuronide. Three isomers belonging to the same class dicaffeoyl derivatives were identified as the cynamoyl derivative (dicaffeoyl quinic acid and 1,5 di-caffeoyl quinic acid) in addition to chlorogenic acid and caffeoyl quinic acid. The quantitative estimation of the compounds identified in vernonia amygdalina (mg/g dried weight) revealed that luteolin-7-O-glucuronide (0.47), luteolin-7-O-glucoside (0.36) were the dominant flavonoid while caffeoyl qunic acid derivatives were shown to be the dominant cinnamoyl derivative; dicaffeoyl quinic acid (0.78), 1,5 dicaffeoyl quinic acid (0.41) . The identified phenolic compounds would contribute to the antioxidant activity elicited by the studied plant due to the established potency of phenolic compounds as antioxidant molecules. (author)

HPLC/DAD/MS analysis of flavonoids and cynamoyl derivatives in Vernonia amygdalina leaves

International Nuclear Information System (INIS)

Salawu, S.O.; Akindahunsi, A.A.; Mulinacci, N.; Giaccherini, C.; Innocenti, M.; Vincieri, F.F.

2007-12-01

Flavonoids and cynamoyl derivatives occurring in Vernonia amygdalina leaves have been identified and quantified. The identified flavonoids were luteolin, luteolin 7-O-glucuronoside, luteolin 7-O-glucoside and other two rutinosides of luteolin, with the sugar moiety linked in 4' and 7' The main flavonoids are luteolin- 7-O-glucoside and luteolin- 7-O-glucuronide. Three isomers belonging to the same class dicaffeoyl derivatives were identified as the cynamoyl derivative (dicaffeoyl quinic acid and 1,5 di-caffeoyl quinic acid) in addition to chlorogenic acid and caffeoyl quinic acid. The quantitative estimation of the compounds identified in vernonia amygdalina (mg/g dried weight) revealed that luteolin-7-O-glucuronide (0.47), luteolin-7-O-glucoside (0.36) were the dominant flavonoid while caffeoyl qunic acid derivatives were shown to be the dominant cinnamoyl derivative; dicaffeoyl quinic acid (0.78), 1,5 dicaffeoyl quinic acid (0.41) . The identified phenolic compounds would contribute to the antioxidant activity elicited by the studied plant due to the established potency of phenolic compounds as antioxidant molecules. (author)

Review of flavonoids: A diverse group of natural compounds with anti-Candida albicans activity in vitro.

Science.gov (United States)

Seleem, Dalia; Pardi, Vanessa; Murata, Ramiro Mendonça

2017-04-01

Flavonoids are a subdivision of polyphenols, a versatile class of natural compounds that represent secondary metabolites from higher plants and are abundant in human diet. Various protective effects of flavonoids have been reported, including antimicrobial and antifungal activities. Due to the nature of oral candidiasis and the increased use of antifungal agents, several drug-resistant strains have emerged making it impractical to rely on one standard therapeutic regime. The aim of this review is to summarize the antifungal activity of some examples of the major subclasses of flavonoids in pure extract forms against C. albicans in vitro, as reported in literature over the past 10 years (2004-2015). In addition, this review outlines the potential mechanism of actions of flavonoids studied in vitro, which may contribute to a better understanding of flavonoids as multi-targets agents in the treatment and/or prevention of oral candidiasis in clinical settings. Copyright © 2016. Published by Elsevier Ltd.

Mutagenicity of Flavonoids Assayed by Bacterial Reverse Mutation (Ames Test

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Eliana Aparecida Varanda

2012-05-01

Full Text Available The mutagenicity of ten flavonoids was assayed by the Ames test, in Salmonella typhimurium strains TA98, TA100 and TA102, with the aim of establishing hydroxylation pattern-mutagenicity relationship profiles. The compounds assessed were: quercetin, kaempferol, luteolin, fisetin, chrysin, galangin, flavone, 3-hydroxyflavone, 5-hydroxyflavone and 7-hydroxyflavone. In the Ames assay, quercetin acted directly and its mutagenicity increased with metabolic activation. In the presence of S9 mix, kaempferol and galangin were mutagenic in the TA98 strain and kaempferol showed signs of mutagenicity in the other strains. The absence of hydroxyl groups, as in flavone, only signs of mutagenicity were shown in strain TA102, after metabolization and, among monohydroxylated flavones (3-hydroxyflavone, 5-hydroxyflavone and 7-hydroxyflavone, the presence of hydroxyl groups only resulted in minor changes. Luteolin and fisetin also showed signs of mutagenicity in strain TA102. Finally, chrysin, which has only two hydroxy groups, at the 5-OH and 7-OH positions, also did not induce mutagenic activity in any of the bacterial strains used, under either activation condition. All the flavonoids were tested at concentrations varying from 2.6 to 30.7 nmol/plate for galangin and 12.1 to 225.0 nmol/plate for other flavonoids. In light of the above, it is necessary to clarify the conditions and the mechanisms that mediate the biological effects of flavonoids before treating them as therapeutical agents, since some compounds can be biotransformed into more genotoxic products; as is the case for galangin, kaempferol and quercetin.

Analysis of Flavonoids in Rhamnus davurica and Its Antiproliferative Activities

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Guilin Chen

2016-09-01

Full Text Available Rhamnus davurica Pall. (R. davurica has been used as a traditional medicinal herb for many years in China and abroad. It has been well documented as a rich source of flavonoids with diversified structures, which in turn results in far-ranging biological activities, such as anti-inflammation, anticancer, antibacterial and antioxidant activities. In order to further correlate their anticancer potentials with the phytochemical components, the fingerprint profile of R. davurica herb from Dongbei was firstly investigated using HPLC-ESI-MS/MS. Thirty two peaks were detected and identified, 14 of which were found in R. davurica for the first time in this work. Furthermore, a total of 23 peaks were resolved as flavonoids, which are the major components found in R. davurica. Meanwhile, the antiproliferative activities against human cancer cells of HT-29 and SGC-7901 in vitro exhibited distinct inhibitory effects with IC50 values at 24.96 ± 0.74 and 89.53 ± 4.11 μg/mL, respectively. Finally, the general toxicity against L-O2 cells displayed a much higher IC50 at 229.19 ± 8.52 μg/mL, which suggested very low or no toxicity on hepatic cell viability. The current study revealed for the first time the correlations between the flavonoids of R. davurica with their antiproliferative activities, which indicated that the fingerprint profile of flavonoids and their anticancer activities could provide valuable information on the quality control for herbal medicines and their derived natural remedies from this valuable medicinal plant.

The Antirrhinum AmDEL gene enhances flavonoids accumulation and salt and drought tolerance in transgenic Arabidopsis.

Science.gov (United States)

Wang, Feibing; Zhu, Hong; Kong, Weili; Peng, Rihe; Liu, Qingchang; Yao, Quanhong

2016-07-01

A basic helix-loop-helix (bHLH) transcription factor gene from Antirrhinum, AmDEL , increases flavonoids accumulation and enhances salt and drought tolerance via up-regulating flavonoid biosynthesis, proline biosynthesis and ROS scavenging genes in transgenic Arabidopsis. In plants, transcriptional regulation is the most important tools for increasing flavonoid biosynthesis. The AmDEL gene, as a basic helix-loop-helix transcription factor gene from Antirrhinum, has been shown to increase flavonoids accumulation in tomato. However, its role in tolerance to abiotic stresses has not yet been investigated. In this study, the codon-optimized AmDEL gene was chemically synthesized. Subcellular localization analysis in onion epidermal cells indicated that AmDEL protein was localized to the nucleus. Expression analysis in yeast showed that the full length of AmDEL exhibited transcriptional activation. Overexpression of AmDEL significantly increased flavonoids accumulation and enhanced salt and drought tolerance in transgenic Arabidopsis plants. Real-time quantitative PCR analysis showed that overexpression of AmDEL resulted in the up-regulation of genes involved in flavonoid biosynthesis, proline biosynthesis and ROS scavenging under salt and drought stresses. Meanwhile, Western blot and enzymatic analyses showed that the activities of phenylalanine ammonia lyase, chalcone isomerase, dihydroflavonol reductase, pyrroline-5-carboxylate synthase, superoxide dismutase and peroxidase were also increased. Further components analyses indicated that the significant increase of proline and relative water content and the significant reduction of H2O2 and malonaldehyde content were observed under salt and drought stresses. In addition, the rates of electrolyte leakage and water loss were reduced in transgenic plants. These findings imply functions of AmDEL in accumulation of flavonoids and tolerance to salt and drought stresses. The AmDEL gene has the potential to be used to increase

Characterization of UGT716A1 as a Multi-substrate UDP:Flavonoid Glucosyltransferase Gene in Ginkgo biloba

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Xiaojia Su

2017-12-01

Full Text Available Ginkgo biloba L., a “living fossil” and medicinal plant, is a well-known rich source of bioactive flavonoids. The molecular mechanism underlying the biosynthesis of flavonoid glucosides, the predominant flavonoids in G. biloba, remains unclear. To better understand flavonoid glucosylation in G. biloba, we generated a transcriptomic dataset of G. biloba leaf tissue by high-throughput RNA sequencing. We identified 25 putative UDP-glycosyltransferase (UGT unigenes that are potentially involved in the flavonoid glycosylation. Among them, we successfully isolated and expressed eight UGT genes in Escherichia coli, and found that recombinant UGT716A1 protein was active toward broad range of flavonoid/phenylpropanoid substrates. In particular, we discovered the first recombinant UGT protein, UGT716A1 from G. biloba, possessing unique activity toward flavanol gallates that have been extensively documented to have significant bioactivity relating to human health. UGT716A1 expression level paralleled the flavonoid distribution pattern in G. biloba. Ectopic over-expression of UGT716A1 in Arabidopsis thaliana led to increased accumulation of several flavonol glucosides. Identification and comparison of the in vitro enzymatic activity of UGT716A1 homologs revealed a UGT from the primitive land species Physcomitrella patens also showed broader substrate spectrum than those from higher plants A. thaliana, Vitis vinifera, and Medicago truncatula. The characterization of UGT716A1 from G. biloba bridges a gap in the evolutionary history of UGTs in gymnosperms. We also discuss the implication of UGT716A1 for biosynthesis, evolution, and bioengineering of diverse glucosylated flavonoids.

Structure-antioxidant activity relationships of flavonoids isolated from the resinous exudate of Heliotropium sinuatum.

Science.gov (United States)

Modak, Brenda; Contreras, M Leonor; González-Nilo, Fernando; Torres, René

2005-01-17

Relationships between the structural characteristics of flavonoids isolated from the resinous exudate of Heliotropium sinuatum and their antioxidant activity were studied. Radical formation energies, DeltaH of dehydrogenation and spin densities were calculated using DFT methods (B3LYP/6-31G*). Results show that studied flavonoids can be divided into two sets according to their activity. It has been found that antioxidant activity depends both on substitution pattern of hydroxyl groups of the flavonoid skeleton and the presence of an unsaturation at the C2-C3 bond. A good tendency between DeltaH of dehydrogenation and antioxidant activity was established.

Structure-activity relationships and molecular docking of thirteen synthesized flavonoids as horseradish peroxidase inhibitors.

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Mahfoudi, Reguia; Djeridane, Amar; Benarous, Khedidja; Gaydou, Emile M; Yousfi, Mohamed

2017-10-01

For the first time, the structure-activity relationships of thirteen synthesized flavonoids have been investigated by evaluating their ability to modulate horseradish peroxidase (HRP) catalytic activity. Indeed, a modified spectrophotometrically method was carried out and optimized using 4-methylcatechol (4-MC) as peroxidase co-substrate. The results show that these flavonoids exhibit a great capacity to inhibit peroxidase with Ki values ranged from 0.14±0.01 to 65±0.04mM. Molecular docking has been achieved using Auto Dock Vina program to discuss the nature of interactions and the mechanism of inhibition. According to the docking results, all the flavonoids have shown great binding affinity to peroxidase. These molecular modeling studies suggested that pyran-4-one cycle acts as an inhibition key for peroxidase. Therefore, potent peroxidase inhibitors are flavonoids with these structural requirements: the presence of the hydroxyl (OH) group in 7, 5 and 4' positions and the absence of the methoxy (O-CH 3 ) group. Apigenin contributed better in HRP inhibitory activity. The present study has shown that the studied flavonoids could be promising HRP inhibitors, which can help in developing new molecules to control thyroid diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Antiproliferative activity of flavonoids on several cancer cell lines.

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Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

1999-05-01

Twenty-seven Citrus flavonoids were examined for their antiproliferative activities against several tumor and normal human cell lines. As a result, 7 flavonoids were judged to be active against the tumor cell lines, while they had weak antiproliferative activity against the normal human cell lines. The rank order of potency was luteolin, natsudaidain, quercetin, tangeretin, eriodictyol, nobiletin, and 3,3',4',5,6,7,8-heptamethoxyflavone. The structure-activity relationship established from comparison among these flavones and flavanones showed that the ortho-catechol moiety in ring B and a C2-C3 double bond were important for the antiproliferative activity. As to polymethoxylated flavones, C-3 hydroxyl and C-8 methoxyl groups were essential for high activity.

Availability of Insurance Linkage Programs in U.S. Emergency Departments

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Mia Kanak

2014-07-01

Full Text Available Introduction: As millions of uninsured citizens who use emergency department (ED services are now eligible for health insurance under the Affordable Care Act, the ED is ideally situated to facilitate linkage to insurance. Forty percent of U.S. EDs report having an insurance linkage program. This is the first national study to examine the characteristics of EDs that offer or do not offer these programs. Methods: This was a secondary analysis of data from the National Survey for Preventive Health Services in U.S. EDs conducted in 2008-09. We compared EDs with and without insurance programs across demographic and operational factors using univariate analysis. We then tested our hypotheses using multivariable logistic regression. We also further examined program capacity and priority among the sub-group of EDs with no insurance linkage program. Results: After adjustment, ED-insurance linkage programs were more likely to be located in the West (RR= 2.06, 95% CI = 1.33 – 2.72. The proportion of uninsured patients in an ED, teaching hospital status, and public ownership status were not associated with insurance linkage availability. EDs with linkage programs also offer more preventive services (RR = 1.87, 95% CI = 1.37–2.35 and have greater social worker availability (RR = 1.71, 95% CI = 1.12–2.33 than those who do not. Four of five EDs with a patient mix of ≥25% uninsured and no insurance linkage program reported that they could not offer a program with existing staff and funding. Conclusion: Availability of insurance linkage programs in the ED is not associated with the proportion of uninsured patients served by an ED. Policy or hospital-based interventions to increase insurance linkage should first target the 27% of EDs with high rates of uninsured patients that lack adequate program capacity. Further research on barriers to implementation and cost effectiveness may help to facilitate increased adoption of insurance linkage programs. [West J

Separation of antioxidant and α-glucosidase inhibitory flavonoids from the aerial parts of Asterothamnus centrali-asiaticus.

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Wang, Yan-Ming; Zhao, Jian-Qiang; Yang, Jun-Li; Tao, Yan-Duo; Mei, Li-Juan; Shi, Yan-Ping

2017-06-01

A new flavonoid, along with 16 known ones, was separated from the aerial parts of Asterothamnus centrali-asiaticus. Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D NMR techniques and HRESIMS. To confirm the structure of the new compound, computational prediction of its 13 C chemical shifts was performed. All of the 17 flavonoids were reported from A. centrali-asiaticus for the first time. In addition, all flavonoids were evaluated for their antioxidant and α-glucosidase inhibitory activities. The results showed that 10 of them exhibited antioxidant activity. Meanwhile, four flavonoids displayed α-glucosidase inhibitory effect with IC 50 values ranging from 38.9 to 299.7 μM.

Radical scavenging propensity of Cu2 +, Fe3 + complexes of flavonoids and in-vivo radical scavenging by Fe3 +-primuletin

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Jabeen, Erum; Janjua, Naveed Kausar; Ahmed, Safeer; Murtaza, Iram; Ali, Tahir; Hameed, Shahid

2017-01-01

Cu2 + and Fe3 + complexes of three flavonoids (morin or mo, quercetin or quer and primuletin or prim) were synthesized with the objective of improving antioxidant capacities of flavonoids. The radical scavenging activities of pure flavonoids and their metal complexes were assayed to monitor their tendencies towards sequestering of radicals at physiological conditions. The scavenger potencies of metal-flavonoid complexes were significantly higher than those of the parent flavonoids. Further, influence of the solvent polarity on the radical capturing by flavonoids and their metal complexes was in favor for the polar solvent. Fe3 +-prim displayed its radical scavenging ability via up gradation of CAT and SOD activities in in-vivo antioxidant assays.

Quantifying sources of bias in longitudinal data linkage studies of child abuse and neglect: measuring impact of outcome specification, linkage error, and partial cohort follow-up.

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Parrish, Jared W; Shanahan, Meghan E; Schnitzer, Patricia G; Lanier, Paul; Daniels, Julie L; Marshall, Stephen W

2017-12-01

Health informatics projects combining statewide birth populations with child welfare records have emerged as a valuable approach to conducting longitudinal research of child maltreatment. The potential bias resulting from linkage misspecification, partial cohort follow-up, and outcome misclassification in these studies has been largely unexplored. This study integrated epidemiological survey and novel administrative data sources to establish the Alaska Longitudinal Child Abuse and Neglect Linkage (ALCANLink) project. Using these data we evaluated and quantified the impact of non-linkage misspecification and single source maltreatment ascertainment use on reported maltreatment risk and effect estimates. The ALCANLink project integrates the 2009-2011 Alaska Pregnancy Risk Assessment Monitoring System (PRAMS) sample with multiple administrative databases through 2014, including one novel administrative source to track out-of-state emigration. For this project we limited our analysis to the 2009 PRAMS sample. We report on the impact of linkage quality, cohort follow-up, and multisource outcome ascertainment on the incidence proportion of reported maltreatment before age 6 and hazard ratios of selected characteristics that are often available in birth cohort linkage studies of maltreatment. Failure to account for out-of-state emigration biased the incidence proportion by 12% (from 28.3% w to 25.2% w ), and the hazard ratio (HR) by as much as 33% for some risk factors. Overly restrictive linkage parameters biased the incidence proportion downwards by 43% and the HR by as much as 27% for some factors. Multi-source linkages, on the other hand, were of little benefit for improving reported maltreatment ascertainment. Using the ALCANLink data which included a novel administrative data source, we were able to observe and quantify bias to both the incidence proportion and HR in a birth cohort linkage study of reported child maltreatment. Failure to account for out

Isolation of flavonoids from Anemopaegma arvense (Vell Stellf. ex de Souza and their antifungal activity against Trichophyton rubrum

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Camila Di Giovane Costanzo

2013-09-01

Full Text Available Anemopaegma arvense (Vell Stellf. ex de Souza belongs to the family Bignoniaceae, and is popularly known as catuaba. To evaluate the cytotoxic and antimicrobial activity of A. arvense, fraction F3 and flavonoids 1 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6-β-D-glucopyranoside (rutin and flavonoid 2 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6-β-D-galactopyranoside were isolated from the leaves of this plant. Fraction F3 and flavonoids 1 and 2 exhibited no antibacterial activity. Furthermore, no cytotoxic activity of fraction 3 or flavonoids 1 and 2 was observed against the tumor cells tested. However, analysis of the antifungal activity of flavonoids 1 and 2 revealed minimum inhibitory concentrations of 0.5 and 0.25 mg/mL, respectively, against the Trichophyton rubrum strains tested (wild type and mutant. This study demonstrates for the first time the antifungal activity of isolated flavonoids, validating the same activity for A. arvense.

Studies on interaction between flavonoids and bovine serum albumin by spectral methods

International Nuclear Information System (INIS)

Shi Xiaolei; Li Xuwen; Gui Mingyu; Zhou Hongyu; Yang Ruijie; Zhang Hanqi; Jin Yongri

2010-01-01

The interaction between three kinds of flavonoids and bovine serum albumin (BSA) was investigated by fluorescence and UV-vis absorption spectrometry. The results indicated that flavonoids have strong ability to quench the intrinsic fluorescence of BSA by forming complexes. The binding constants, number of binding sites, thermodynamic parameters and energy transfer mechanisms were also investigated. Conformation change of BSA was observed from synchronous, three-dimensional fluorescence and circular dichroism spectrum.

Identification and assay of the flavonoids in medicinal plants with hepatoprotective action

OpenAIRE

Cojocaru-Toma M.

2015-01-01

The article describes the identification and assay of the flavonoids in medicinal plants with hepatoprotective action, harvested as a culture at the Cultivation Center of the Medicinal Plants within State University of Medicine and Pharmacy „Nicolae Testemițanu” from the Republic of Moldova, using Pharmacopoeia methods. The flavonoids, found in the examined medicinal product, are responsible for hepatoprotective activity due to antioxidant activity, exhibited by neutralizing free radicals. Th...

Flavonoids and Phenolic Acids from Oregano: Occurrence, Biological Activity and Health Benefits

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Erick P. Gutiérrez-Grijalva; Manuel A. Picos-Salas; Nayely Leyva-López; Marilyn S. Criollo-Mendoza; Gabriela Vazquez-Olivo; J. Basilio Heredia

2017-01-01

Several herb species classified as oregano have been widely used in folk medicine to alleviate inflammation-related diseases, respiratory and digestive disorders, headaches, rheumatism, diabetes and others. These potential health benefits are partially attributed to the phytochemical compounds in oregano such as flavonoids (FL) and phenolic acids (PA). Flavonoids and phenolic acids are among the most abundant and most studied phytochemicals in oregano species. Epidemiological, in vitro and in...

Quantitative determination of total and individual flavonoids in stems and leaves of Buddleja davidii and Buddleja albiflora.

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Ying, Cheng; Wan, Dingrong

2012-10-01

Buddleja davidii and B. albiflora are two different original plants of the famous crude medicine "Diaoyangchen". An ultraviolet-visible spectrophotometric method and a HPLC method were used for the determination of total and individual flavonoids (luteolin and apigenin) contents from their stems and leaves for the first time. From the comparative evaluation, remarkable differences in flavonoids contents were observed between different origins and different parts of the samples. And content of specific flavonoid did not correspond to the total flavonoids contents in Buddleja davidii and Buddleja albiflora. With a better accuracy and precision, the methods had been proved simple, rapid, and reliable for quantitative determination of the total flavonoids and luteolin and apigenin in the two phytomedicines. Furthermore, our present study will pave the way of guidelines for the differentiation and standardization and exploitation of individual parts of this herb material.

Antigenotoxic prenylated flavonoids from stem bark of Erythrina latissima.

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Zarev, Yancho; Foubert, Kenn; Lucia de Almeida, Vera; Anthonissen, Roel; Elgorashi, Esameldin; Apers, Sandra; Ionkova, Iliana; Verschaeve, Luc; Pieters, Luc

2017-09-01

A series of prenylated flavonoids was obtained from antigenotoxic extracts and fractions of stem bark of Erythrina latissima E. Mey (Leguminosae). In addition to five constituents never reported before, i.e. (2S)-5,7-dihydroxy-2-(4-hydroxy-2-(prop-1-en-2-yl)-2,3-dihydrobenzofuran-6-yl)chroman-4-one (erylatissin D), (2S)-5,7-dihydroxy-2-(4-methoxy-2-(prop-1-en-2-yl)-2,3-dihydrobenzofuran-6-yl)chroman-4-one (erylatissin E), 5,7-dihydroxy-3-(4-methoxy-2-(prop-1-en-2-yl)-2,3-dihydrobenzofuran-6-yl)-4H-chromen-4-one (erylatissin F), (2S)-5,7,8'-trihydroxy-2',2'-dimethyl-[2,6'-bichroman]-4-one (erylatissin G) and (2S)-5,7-dihydroxy-8'-methoxy-2',2'-dimethyl-[2,6'-bichroman]-4-one (dihydroabyssinin I), 18 known flavonoids were identified. Evaluation of the antigenotoxic properties (against genotoxicity induced by aflatoxin B1, metabolically activated) in the Vitotox assay revealed that most flavonoids were active. Sigmoidin A and B showed the highest activity, with an IC 50 value of 18.7 μg/mL, equivalent to that of curcumin (IC 50 18.4 μg/mL), used as a reference antigenotoxic compound. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antiplasmodial and larvicidal flavonoids from Derris trifoliata

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ABSTRACT. ABSTRACT. From the dichloromethane-methanol (1:1) extract of the seed pods of Derris trifoliata, a new flavanone derivative (S)-lupinifolin 4´-methyl ether was isolated. In addition, the known flavonoids lupinifolin and rotenone were identified. The structures were determined on the basis of spectroscopic ...

[Correlation analysis of nutrients and microorganisms in soils with polyphenols and total flavonoids of Houttuynia cordata].

Science.gov (United States)

Wu, Dan; Luo, Shi-qiong; Yang, Zhan-nan; Ma, Jing; Hong, Liang

2015-04-01

The relationship of nutrients and microorganisms in soils with polyphenols and total flavonoids of Houttuynia cordata were investigated by measuring nutrients, enzyme activity, pH, concentrations of microbe phospholipid fatty acids (PLFAs) in soils, and determining concentrations of polyphenols and total flavonoids of H. cordata. The research is aimed to understand characteristics of the planting soils and improve the quality of cultivated H. cordata. The soils at different sample sites varied greatly in nutrients, enzyme activity, pH, microbic PLFAs and polyphenols and all flavonoids. The content of total PLFAs in sample sites was following: bacteria > fungi > actinomyces > nematode. The content of bacteria PLFAs was 37.5%-65.0% at different sample sites. Activities of polyphenol oxidease, concentrations of available P and content of PLFAs of bacteria, actinomyces and total microorganisms in soils were significantly and positively related to the concentrations of polyphenols and total flavonoids of H. cordata, respectively (P soils was significantly and negatively related to concentrations of polyphenols and total flavonoids of H. cordata, respectively (P soil nutrient, which may be improved due to transformation of soil microorganisms and enzymes to N and P in the soils, was beneficial to adaptation of H. cordata adapted to different soil conditions, and significantly affects metabolic accumulation of polyphenols and flavonoids of H. cordata.

Phytochemical screening, total phenolic, total flavonoids contents and antioxidant activity of cinchona ledgeriana leaves ethanol extract

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Sundowo, Andini; Artanti, Nina; Hanafi, M.; Minarti, Primahana, Gian

2017-11-01

C ledgeriana is a medicinal plant that contains alkaloids, especially on the barks for commercial production of quinine as antimalarial. The main alkaloids in this plant are cinchonine, cinchonidine, quinine and quinidine. Besides for antiamalarial this plant is also commonly used to treat whooping cough, influenza and dysentery. Compare to other medicinal plants, nowadays only very few studies were conducted in Cinchona species. Our current study aims to determine the content of phytochemical, total phenol and total flavonoids from C. ledgeriana leaves 70% ethanol extract. The extraction was performed by maceration method using 70% ethanol solvent and then fractionated into hexane, ethylacetate and butanol. Phytochemical screening was performed to determine the content of alkaloids, flavonoids, terpenoids, tannins and saponins. Total phenol and flavonoid contents of the extract were determined by Folin-Ciocalteu and alumunium chloride colorimetric methods using gallic acid and quercetin as standards. The antioxidant activity was determined by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The results of phytochemical screening showed that the 70% ethanol extract of C. ledgeriana leaves contained alkaloids, flavonoids, terpenoids, tannins and saponins. The total phenol and total flavonoids analysis showed that ethyl acetate fraction had the highest total phenol (40.23%) and total flavonoids (65.34%).

Extraction and Purification of Flavonoids from Radix Puerariae

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and preparations are now on sale. ... significant for optimization of extraction, resin selection and ... and flavonoids as indexes, optimize the proper density. ..... system. Sep Purif Technol. 2008; 62: 590-595. 12. Chen JH, Liau BC, Jong TT.

The regioselectivity of glutathione adduct formation with flavonoid quinone methides is pH-dependent