WorldWideScience

Sample records for intracellular polyphenol oxidases

  1. Polyphenol Oxidase Enzyme and Inactivation Methods

    Directory of Open Access Journals (Sweden)

    Leman Yılmaz

    2018-03-01

    Full Text Available Polyphenol oxidase enzyme is found in vegetables and fruits, as well as in some animal organs and microorganisms. Polyphenol oxidase enzyme responsible for enzymatic browning is a group of copper proteins that catalyses the oxidation of phenolic compounds to quinones, which produce brown pigments, commonly found in fruits and vegetables. During the industrial preparation of fruits and vegetables, results of catalytic effect of polyphenol oxidase causes enzymatic browning. Enzymatic browning impairs the appearance of products containing phenolic compounds along with undesirable colour, odor and taste formation and significant loss of nutritional value of the products. This affects the acceptability of the products by the consumers and causes economic losses. In this review, some characteristics of polyphenol oxidase enzyme in different fruits and vegetables have been reviewed and information about chemical antibrowning agents, thermal applications, irradiation applications and alternative methods such as high pressure processing, pulse electric field, supercritical carbon dioxide and ultrasound applications to inactivate this enzyme has been presented.

  2. Forage Polyphenol Oxidase and Ruminant Livestock Nutrition

    Directory of Open Access Journals (Sweden)

    Michael Richard F. Lee

    2014-12-01

    Full Text Available Polyphenol oxidase (PPO is associated with the detrimental effect of browning fruit and vegetables, however interest within PPO containing forage crops has grown since the brownng reaction was associated with reduced nitrogen (N losses in silo and the rumen. The reduction in protein breakdown in silo of red clover (high PPO forage increased the quality of protein, improving N-use efficiency (NUE when fed to ruminants. A further benefit of red clover silage feeding is a significant reduction in lipolysis in silo and an increase in the deposition of beneficial C18 polyunsaturated fatty acid (PUFA in animal products, which has also been linked to PPO activity. PPOs protection of plant protein and glycerol based-PUFA in silo is related to the deactivation of plant proteases and lipases. This deactivation occurs through PPO catalysing the conversion of diphenols to quinones which bind with cellular nucleophiles such as protein reforming a protein-bound phenol (PBP. If the protein is an enzyme the complexing denatures the enzyme. However, PPO is inactive in the anaerobic rumen and therefore any subsequent protection of plant protein and glycerol based-PUFA in the rumen must be as a result of events that occurred to the forage pre-ingestion. Reduced activity of plant proteases and lipases would have little effect on NUE and glycerol based-PUFA in the rumen due to the greater concentration of rumen microbial proteases and lipases. The mechanism for PPOs protection of plant protein in the rumen is a consequence of complexing plant protein, rather than protease deactivation per se. These complexed proteins reduce protein digestibility in the rumen and subsequently increase un-degraded dietary protein flow to the small intestine. The mechanism for protecting glycerol-based PUFA has yet to be fully elucidated but may be associated with entrapment within PBP reducing access to microbial lipases or differences in rumen digestion kinetics of red clover.

  3. Effect of heat treatment on polyphenol oxidase and peroxidase ...

    African Journals Online (AJOL)

    Effect of heat treatment (55°C/20 min) on polyphenol oxidase (PPO) and peroxidase (POD) activities and total phenolic compounds was investigated in Algerian dates (Deglet Nour variety) at Tamar (fully ripe) stage and in dates stored for 5 months at ambient temperature and in cold storage (10°C). Results obtained ...

  4. Analysis of cellulase and polyphenol oxidase production by southern pine beetle associated fungi

    Science.gov (United States)

    Abduvali Valiev; Zumrut B. Ogel; Dier D. Klepzig

    2009-01-01

    In this study, the production of extracellular enzymes by fungi associated with southern pine beetle was investigated for the first time. Cellulase and polyphenol oxidase production were analyzed for three beetle associated fungi. Only the mutualistic symbiont Entomocorticium sp. A was found to produce cellulases and polyphenol oxidase....

  5. Polyphenol Oxidases in Crops: Biochemical, Physiological and Genetic Aspects

    Directory of Open Access Journals (Sweden)

    Francesca Taranto

    2017-02-01

    Full Text Available Enzymatic browning is a colour reaction occurring in plants, including cereals, fruit and horticultural crops, due to oxidation during postharvest processing and storage. This has a negative impact on the colour, flavour, nutritional properties and shelf life of food products. Browning is usually caused by polyphenol oxidases (PPOs, following cell damage caused by senescence, wounding and the attack of pests and pathogens. Several studies indicated that PPOs play a role in plant immunity, and emerging evidence suggested that PPOs might also be involved in other physiological processes. Genomic investigations ultimately led to the isolation of PPO homologs in several crops, which will be possibly characterized at the functional level in the near future. Here, focusing on the botanic families of Poaceae and Solanaceae, we provide an overview on available scientific literature on PPOs, resulting in useful information on biochemical, physiological and genetic aspects.

  6. Temperature dependence of the activity of polyphenol peroxidases and polyphenol oxidases in modern and buried soils

    Science.gov (United States)

    Yakushev, A. V.; Kuznetsova, I. N.; Blagodatskaya, E. V.; Blagodatsky, S. A.

    2014-05-01

    Under conditions of the global climate warming, the changes in the reserves of soil humus depend on the temperature sensitivities of polyphenol peroxidases (PPPOs) and polyphenol oxidases (PPOs). They play an important role in lignin decomposition, mineralization, and humus formation. The temperature dependence of the potential enzyme activity in modern and buried soils has been studied during incubation at 10 or 20°C. The experimental results indicate that it depends on the availability of the substrate and the presence of oxygen. The activity of PPOs during incubation in the absence of oxygen for two months decreases by 2-2.5 times, which is balanced by an increase in the activity of PPPOs by 2-3 times. The increase in the incubation temperature to 20°C and the addition of glucose accelerates this transition due to the more abrupt decrease in the activity of PPOs. The preincubation of the soil with glucose doubles the activity of PPPOs but has no significant effect on the activity of PPOs. The different effects of temperature on two groups of the studied oxidases and the possibility of substituting enzymes by those of another type under changing aeration conditions should be taken into consideration in predicting the effect of the climate warming on the mineralization of the soil organic matter. The absence of statistically significant differences in the enzymatic activity between the buried and modern soil horizons indicates the retention by the buried soil of some of its properties (soil memory) and the rapid restoration of high enzymatic activity during the preincubation.

  7. Characterization of polyphenol oxidase from blueberry (Vaccinium corymbosum L.).

    Science.gov (United States)

    Siddiq, M; Dolan, K D

    2017-03-01

    Polyphenol oxidase (PPO) was extracted and characterized from high-bush blueberries. PPO showed an optimum activity at pH 6.1-6.3 and 35°C, with the enzyme showing significant activity over a wide temperature range (25-60°C). Catechol was the most readily oxidized substrate followed by 4-methylcatechol, DL-DOPA, and dopamine. Blueberry PPO showed a K m of 15mM and V max of 2.57 ΔA 420 nm/min×10 -1 , determined with catechol. PPO was completely inactivated in 20min at 85°C, however, after 30minat 75°C it showed about 10% residual activity. Thermal treatment at 55 and 65°C for 30min resulted in the partial inactivation of PPO. Ascorbic acid, sodium diethyldithiocarbamic acid, L-cysteine, and sodium metabisulfite were effective inhibitors of PPO at 1.0mM. Benzoic acid and cinnamic acid series inhibitors showed relatively weak inhibition of PPO (21.8-27.6%), even at as high as 2.0mM concentration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Polyphenol Oxidase as a Biochemical Seed Defense Mechanism

    Directory of Open Access Journals (Sweden)

    E. Patrick Fuerst

    2014-12-01

    Full Text Available Seed dormancy and resistance to decay are fundamental survival strategies, which allow a population of seeds to germinate over long periods of time. Seeds have physical, chemical, and biological defense mechanisms that protect their food reserves from decay-inducing organisms and herbivores. Here, we hypothesize that seeds also possess enzyme-based biochemical defenses, based on induction of the plant defense enzyme, polyphenol oxidase (PPO, when wild oat (Avena fatua L. caryopses and seeds were challenged with seed-decaying Fusarium fungi. These studies suggest that dormant seeds are capable of mounting a defense response to pathogens. The pathogen-induced PPO activity from wild oat was attributed to a soluble isoform of the enzyme that appeared to result, at least in part, from proteolytic activation of a latent PPO isoform. PPO activity was also induced in wild oat hulls (lemma and palea, non-living tissues that cover and protect the caryopsis. These results are consistent with the hypothesis that seeds possess inducible enzyme-based biochemical defenses arrayed on the exterior of seeds and these defenses represent a fundamental mechanism of seed survival and longevity in the soil. Enzyme-based biochemical defenses may have broader implications since they may apply to other defense enzymes as well as to a diversity of plant species and ecosystems.

  9. Functional Analysis of Polyphenol Oxidases by Antisense/Sense Technology

    Directory of Open Access Journals (Sweden)

    Jutharat Attajarusit

    2007-07-01

    Full Text Available Polyphenol oxidases (PPOs catalyze the oxidation of phenolics to quinones, the secondary reactions of which lead to oxidative browning and postharvest losses of many fruits and vegetables. PPOs are ubiquitous in angiosperms, are inducible by both biotic and abiotic stresses, and have been implicated in several physiological processes including plant defense against pathogens and insects, the Mehler reaction, photoreduction of molecular oxygen by PSI, regulation of plastidic oxygen levels, aurone biosynthesis and the phenylpropanoid pathway. Here we review experiments in which the roles of PPO in disease and insect resistance as well as in the Mehler reaction were investigated using transgenic tomato (Lycopersicon esculentum plants with modified PPO expression levels (suppressed PPO and overexpressing PPO. These transgenic plants showed normal growth, development and reproduction under laboratory, growth chamber and greenhouse conditions. Antisense PPO expression dramatically increased susceptibility while PPO overexpression increased resistance of tomato plants to Pseudomonas syringae. Similarly, PPO-overexpressing transgenic plants showed an increase in resistance to various insects, including common cutworm (Spodoptera litura (F., cotton bollworm (Helicoverpa armigera (Hübner and beet army worm (Spodoptera exigua (Hübner, whereas larvae feeding on plants with suppressed PPO activity had higher larval growth rates and consumed more foliage. Similar increases in weight gain, foliage consumption, and survival were also observed with Colorado potato beetles (Leptinotarsa decemlineata (Say feeding on antisense PPO transgenic tomatoes. The putative defensive mechanisms conferred by PPO and its interaction with other defense proteins are discussed. In addition, transgenic plants with suppressed PPO exhibited more favorable water relations and decreased photoinhibition compared to nontransformed controls and transgenic plants

  10. Impacts on the metabolome of down-regulating polyphenol oxidase in transgenic potato tubers

    Science.gov (United States)

    Tubers of potato (Solanum tuberosum L. cv. Estima) genetically modified (GM) to reduce polyphenol oxidase (PPO) activity and enzymatic discolouration were assessed for changes in the metabolome using Liquid Chromatography-Mass Spectrometry (LC-MS) and Gas Chromatography (GC)-MS. Metabolome changes ...

  11. Tissue Printing to Visualize Polyphenol Oxidase and Peroxidase in Vegetables, Fruits, and Mushrooms

    Science.gov (United States)

    Melberg, Amanda R.; Flurkey, William H.; Inlow, Jennifer K.

    2009-01-01

    A simple tissue-printing procedure to determine the tissue location of the endogenous enzymes polyphenol oxidase and peroxidase in a variety of vegetables, fruits, and mushrooms is described. In tissue printing, cell contents from the surface of a cut section of the tissue are transferred to an adsorptive surface, commonly a nitrocellulose…

  12. Potato and Mushroom Polyphenol Oxidase Activities Are Differently Modulated by Natural Plant Extracts

    NARCIS (Netherlands)

    Kuijpers, T.F.M.; Herk, van T.; Vincken, J.P.; Janssen, R.H.; Narh, D.L.; Berkel, van W.J.H.; Gruppen, H.

    2014-01-01

    Enzymatic browning is a major quality issue in fruit and vegetable processing and can be counteracted by different natural inhibitors. Often, model systems containing a single polyphenol oxidase (PPO) are used to screen for new inhibitors. To investigate the impact of the source of PPO on the

  13. Effect of high pressure on peanut allergens in the presence of polyphenol oxidase and caffeic acid

    Science.gov (United States)

    High pressure (HP) enhances enzymatic reactions. Because polyphenol oxidase (PPO) is an enzyme, and reduces IgE binding of peanut allergens in presence of caffeic acid (CA), we postulated that a further reduction in IgE binding can be achieved, using HP together with PPO and CA. Peanut extracts cont...

  14. Immunological and molecular comparison of polyphenol oxidase in Rosaceae fruit trees.

    Science.gov (United States)

    Haruta, M; Murata, M; Kadokura, H; Homma, S

    1999-03-01

    An antibody raised against apple polyphenol oxidase (PPO) cross-reacted with PPOs from Japanese pear (Pyrus pyrifolia), pear (Pyrus communis), peach (Prunus persica), Chinese quince (Pseudocydonia sinensis) and Japanese loquat (Eriobotrya japonica). Core fragments (681 bp) of the corresponding PPO genes were amplified and characterized. The deduced protein sequences showed identities of 85.3 to 97.5%. Chlorogenic acid oxidase activity of these PPOs showed higher activities when assayed at pH 4 than at pH 6. These results indicate that PPOs in Rosaceae plants are structurally and enzymatically similar.

  15. Optimum pH and pH Stability of Crude Polyphenol Oxidase (PPO ...

    African Journals Online (AJOL)

    The effect of pH on the activity and stability of crude polyphenol oxidase (PPO) extracted from garden egg (Solanum aethiopicum), pawpaw (Carica papaya), pumpkin ... Optimum pH values were found to be 6.0,6.5,6.0, 4.5 and 4.0/or 8.0 for the enzyme extracted from Solanum aethiopicum, Carica papaya, Cucurbita pepo, ...

  16. Immobilization of the enzyme polyphenol oxidase on dendrispheres: In partial fulfilment of the degree Magister Scientiae

    CSIR Research Space (South Africa)

    Bannister, M

    2011-04-01

    Full Text Available OF THE ENZYME POLYPHENOL OXIDASE ON DENDRISPHERES IN PARTIAL FULFILMENT OF THE DEGREE MAGISTER SCIENTIAE Magdalien Bannister 26112664 April 2011 TEA (Camellia sinensis plant) ? CSIR 2011 Slide 2 Second most consumed beverage in the world Grouped into...: ?Green tea Non-fermented ?Oolong tea Partially fermented ?Black tea Fermented Catechins: ?Major component present in green tea leaves ?(-)-Epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG) and (-)-epicatechin...

  17. Molecular Modeling of Peroxidase and Polyphenol Oxidase: Substrate Specificity and Active Site Comparison

    Directory of Open Access Journals (Sweden)

    Lalida Shank

    2010-09-01

    Full Text Available Peroxidases (POD and polyphenol oxidase (PPO are enzymes that are well known to be involved in the enzymatic browning reaction of fruits and vegetables with different catalytic mechanisms. Both enzymes have some common substrates, but each also has its specific substrates. In our computational study, the amino acid sequence of grape peroxidase (ABX was used for the construction of models employing homology modeling method based on the X-ray structure of cytosolic ascorbate peroxidase from pea (PDB ID:1APX, whereas the model of grape polyphenol oxidase was obtained directly from the available X-ray structure (PDB ID:2P3X. Molecular docking of common substrates of these two enzymes was subsequently studied. It was found that epicatechin and catechin exhibited high affinity with both enzymes, even though POD and PPO have different binding pockets regarding the size and the key amino acids involved in binding. Predicted binding modes of substrates with both enzymes were also compared. The calculated docking interaction energy of trihydroxybenzoic acid related compounds shows high affinity, suggesting specificity and potential use as common inhibitor to grape ascorbate peroxidase and polyphenol oxidase.

  18. Extra virgin olive oil rich in polyphenols modulates VEGF-induced angiogenic responses by preventing NADPH oxidase activity and expression.

    Science.gov (United States)

    Calabriso, Nadia; Massaro, Marika; Scoditti, Egeria; D'Amore, Simona; Gnoni, Antonio; Pellegrino, Mariangela; Storelli, Carlo; De Caterina, Raffaele; Palasciano, Giuseppe; Carluccio, Maria Annunziata

    2016-02-01

    Previous studies have shown the antiinflammatory, antioxidant and antiangiogenic properties by pure olive oil polyphenols; however, the effects of olive oil phenolic fraction on the inflammatory angiogenesis are unknown. In this study, we investigated the effects of the phenolic fraction (olive oil polyphenolic extract, OOPE) from extra virgin olive oil and related circulating metabolites on the VEGF-induced angiogenic responses and NADPH oxidase activity and expression in human cultured endothelial cells. We found that OOPE (1-10 μg/ml), at concentrations achievable nutritionally, significantly reduced, in a concentration-dependent manner, the VEGF-induced cell migration, invasiveness and tube-like structure formation through the inhibition of MMP-2 and MMP-9. OOPE significantly (Pextra virgin olive oil, with high polyphenol content, decreased VEGF-induced NADPH oxidase activity and Nox4 expression, as well as, MMP-9 expression, as compared with fasting control serum. Overall, native polyphenols and serum metabolites of extra virgin olive oil rich in polyphenols are able to lower the VEGF-induced angiogenic responses by preventing endothelial NADPH oxidase activity and decreasing the expression of selective NADPH oxidase subunits. Our results provide an alternative mechanism by which the consumption of olive oil rich in polyphenols may account for a reduction of oxidative stress inflammatory-related sequelae associated with chronic degenerative diseases. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. The Effects of Polyphenol Oxidase and Cycloheximide on the Early Stage of Browning in Phalaenopsis Explants

    Directory of Open Access Journals (Sweden)

    Xu Chuanjun

    2015-11-01

    Full Text Available Explant browning is one of the major problems in the tissue culture process, and polyphenol oxidase (PPO, is the major proteases involved in plant tissue browning. We investigated the effects of polyphenol oxidase on the early stage of browning in explants of the orchid Phalaenopsis. Our results show that PPO activity was significantly higher in explants cultured for 3 d than in the 0 h control. The levels of PPO transcripts and PPO protein were significantly higher in explants cultured for 6 h compared to the 0 h control; these high expression levels were maintained over increasing cultivation time. Cycloheximide (CHX treatment reduced PPO transcript levels, PPO protein levels, and PPO enzyme activity. High levels of PPO mRNA and PPO protein were detected in the cytoplasm and vascular bundles of Phalaenopsis explants cultured for 6 h compared to explants cultured for 0 h, 24 h, and 3 d. CHX treatment did not significantly affect the distribution of PPO mRNA and PPO protein in explant tissues, but their levels were significantly lower than those of the untreated control.

  20. Association of molecular markers with polyphenol oxidase activity in selected wheat genotypes

    International Nuclear Information System (INIS)

    Abbas, Z.; Javad, B.; Majeed, N.; Naqvi, S.

    2016-01-01

    Wheat (Triticum aestivum L.), a major staple food for the people of Pakistan and other Asian countries, is used as bread, chapatti, porridge, noodles and many other. It is established that color quality of wheat products depend on chemical and enzymatic factors especially the polyphenol oxidases (PPOs). These are copper containing enzymes which induce browning in wheat-based products. Various procedures for determining PPO activity available and differences in PPO activity among wheat genotypes have been documented. In present study, an attempt was made to establish the association of molecular markers with polyphenol oxidase activity in wheat genotypes having very high or very low PPO activities. Twelve pairs of markers were used out of which only three primer pairs viz. PPO43, PPO30 and WP2-2 yielded specific pattern discriminating high and low PPO genotypes. Cluster analysis for all 12 markers revealed that all the low PPO lline share the same sub cluster, but high PPO lines were dispersed in different clusters. (author)

  1. Effect of temperature stress on polyphenol oxidase activity in grains of some wheat cultivars

    International Nuclear Information System (INIS)

    Kayani, W.K.

    2011-01-01

    Color is a key quality trait of wheat-based products and polyphenol oxidase (PPO) is implicated to play a significant role in their undesirable darkening. Polyphenol oxidase catalyzes the oxidation of phenols to quinines, which auto oxidize and polymerize with amino acid of cellular proteins resulting brown and black pigmentation propounding reduced nutritional values. In present study, the PPO activity in 50 different Pakistani wheat cultivars was investigated and grouped into three categories viz; low, medium and high PPO activity cultivars. PPO is a heat labile enzyme. To investigate effect of heat stress, nine cultivars from each category were chosen for treatment at 30, 40 and 50 deg. C for 30, 60, and 120 minutes each. A substantial change was experienced in PPO activity as compared to room temperature. Two wheat cultivar Wafaq-2001 and AS-2002 showed a compromising attitude of minimum PPO activity at 30 deg. C for a period of 30 and 60 minutes of incubation. In general, an incubation of 30 deg. C or 60 deg. C (low or high) for a period of 30 minutes can be recommended for suppressing PPO activity. (author)

  2. Comparison of content in phenolic compounds, polyphenol oxidase and peroxidase in grains of fifty sorghum cultivars from Burkina Faso.

    NARCIS (Netherlands)

    Dicko, M.H.; Hilhorst, M.H.; Gruppen, H.; Traore, A.S.; Laane, N.C.M.; Berkel, van W.J.H.; Voragen, A.G.J.

    2002-01-01

    Analysis of fifty sorghum [Sorghum bicolor (L.) Moench] varieties used in Burkina Faso showed that they have different contents of phenolic compounds, peroxidase (POX), and polyphenol oxidase (PPO). Most of the varieties (82%) had a tannin content less than 0.25% (w/w). POX specific activity was

  3. Genetic Variation of Isozyme Polyphenol Oxidase (PPO Profiles in Different Varieties of Capsicum annuum L.

    Directory of Open Access Journals (Sweden)

    Owk ANIEL KUMAR

    2013-12-01

    Full Text Available The genus Capsicum commonly known as chilli pepper is a major spice crop and is of cosmopolitan in distribution. Native polyacrylamide gel electrophoresis (Native PAGE was used to study the polyphenol oxidase (PPO isozyme variation in 21 varieties of Capsicum annuum L. A maximum of 4 PPO bands were scored in five varieties i.e., Ca14, Ca15, Ca16, Ca19 & Ca20, while the minimum (2 bands was observed in four varieties (Ca3, Ca10, Ca13 & Ca17. 15 pair wise combinations showed highest average per cent similarity (100% and the UPGMA dendrogram represented low genetic diversity. The present study revealed that considerable intraspecific differences were found in the varieties. Thus the results obtained could be used in fingerprinting the genotypes.

  4. Polyphenol oxidase and peroxidase expression in four pineapple varieties (Ananas comosus L.) after a chilling injury.

    Science.gov (United States)

    Raimbault, Astrid-Kim; Marie-Alphonsine, Paul-Alex; Horry, Jean-Pierre; Francois-Haugrin, Madlyn; Romuald, Karell; Soler, Alain

    2011-01-12

    Pineapple internal browning (IB) is a chilling injury that produces enzymatic browning associated with flesh translucency. Pineapple biodiversity allowed the investigation of how polyphenol oxidase (PPO) and peroxidase (POD) activities with their different isoforms are involved in the IB mechanism. Fruits of four varieties that expressed IB symptoms differently, Smooth Cayenne (SCay) and the hybrids MD2, Flhoran 41 (Flh 41), and Flhoran 53 (Flh 53), were stressed by cold. The susceptible varieties showed classical brown spots but different patterns of IB, whereas MD2 and controls showed no IB. Enzymatic activities were measured on fruit protein extracts and PPO and POD isoforms separated on mini-gels (PhastSystem). Only PPO activity was significantly enhanced in the presence of IB. Up to six PPO isoforms were identified in the susceptible varieties. PPO was barely detectable in the nonsusceptible variety MD2 and in controls. The number of PPO isoforms and the total PPO activity after chilling are varietal characteristics.

  5. Purification and characterization of polyphenol oxidase from cauliflower (Brassica oleracea L.).

    Science.gov (United States)

    Rahman, Andi Nur Faidah; Ohta, Mayumi; Nakatani, Kazuya; Hayashi, Nobuyuki; Fujita, Shuji

    2012-04-11

    Polyphenol oxidase (PPO) of cauliflower was purified to 282-fold with a recovery rate of 8.1%, using phloroglucinol as a substrate. The enzyme appeared as a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The estimated molecular weight of the enzyme was 60 and 54 kDa by SDS-PAGE and gel filtration, respectively. The purified enzyme, called phloroglucinol oxidase (PhO), oxidized phloroglucinol (K(m) = 3.3 mM) and phloroglucinolcarboxylic acid. The enzyme also had peroxidase (POD) activity. At the final step, the activity of purified cauliflower POD was 110-fold with a recovery rate of 3.2%. The PhO and POD showed the highest activity at pH 8.0 and 4.0 and were stable in the pH range of 3.0-11.0 and 5.0-8.0 at 5 °C for 20 h, respectively. The optimum temperature was 55 °C for PhO and 20 °C for POD. The most effective inhibitor for PhO was sodium diethyldithiocarbamate at 10 mM (IC(50) = 0.64 and K(i) = 0.15 mM), and the most effective inhibitor for POD was potassium cyanide at 1.0 mM (IC(50) = 0.03 and K(i) = 29 μM).

  6. Isolation and properties of polyphenol oxidase from basidiocarps of Lactarius pergamenus Fr. (Fr. fungi

    Directory of Open Access Journals (Sweden)

    M. V. Tsivinska

    2015-04-01

    Full Text Available Fresh juice of basidiocarps of Lactarius pergamenus Fr. (Fr. fungi was subjected to ion exchange chromatography with used DEAE-toyopearl and CM-cellulose columns, as well as preparative electrophoresis in 7.5% polyacrylamide gels (pH 8.6. Three isoforms of polyphenol oxidase (PPO were discovered and two isoforms (1-1 and 1-2 were purified with a release of protein 0.42 mg/kg and 0.15 mg/kg of basidiocarps, respectively. These isoforms differ in the mobility at disc-electrophoresis in 7.5% PAGE in alkaline buffer system (pH 8.6. Specific activity of isoform 1-2 is 4.8 times higher than that of the isoforms 1-1. The molecular weight determination by gel chromatography on the Toyopearl HW-55 demonstrated that both isoforms 1-1 and 1-2 have the same 64 ± 2 kDa molecular mass. Electrophoresis in 15% PAGE in the presence of sodium dodecylsulphate and β-mercaptoethanol revealed one band with molecular mass of 64 ± 1 kDa which suggests the presence of one polypeptide chain in the molecule of the enzyme. The enzyme has demonstrated the highest activity at pH 6.0 and temperature +10 ºC, and at +70 ºC the enzyme was inactivated. The PPO activity was the highest in young mushrooms and it decreased with their age and positively correlated with the content of the milky juice. Ortho-aminophenol was most effective among all the tested substrates to determine the activity of PPO (o-, m– and p-aminophenol, catechol, tyrosine, resorcinol, phloroglucinol and its relative activity was 129% of the activity of catechol. Ascorbic acid was the most effective inhibitor of the polyphenol oxidase activity which was completely blocked at 1 mM concentration, whereas the same concentration of thiourea and sodium sulphite decreased the enzymatic activity by 40-45%. The PPO in L. pergamenus fungi basidiocarps was mainly localized in the mushroom milky juice where its high activity may be associated with protection of basidiocarps against various pathogens.

  7. The In Vitro Antioxidant Activity and Inhibition of Intracellular Reactive Oxygen Species of Sweet Potato Leaf Polyphenols

    Directory of Open Access Journals (Sweden)

    Hongnan Sun

    2018-01-01

    Full Text Available The in vitro antioxidant activity and inhibition of intracellular reactive oxygen species (ROS of the total and individual phenolic compounds from Yuzi No. 7 sweet potato leaves were investigated in this study. Sweet potato leaf polyphenols possessed significantly higher antioxidant activity than ascorbic acid, tea polyphenols, and grape seed polyphenols. Among the individual phenolic compounds, caffeic acid showed the highest antioxidant activity, followed by monocaffeoylquinic acids and dicaffeoylquinic acids, while 3,4,5-tri-O-caffeoylquinic acid showed the lowest value. Sweet potato leaf polyphenols could significantly decrease the level of intracellular ROS in a dose-dependent manner. The order of the inhibiting effect of individual phenolic compounds on the intracellular ROS level was not in accordance with that of antioxidant activity, suggesting that there was no direct relationship between antioxidant activity and intracellular ROS-inhibiting effect. Sweet potato leaves could be a good source of biologically active polyphenols with multiple applications in the development of foods, health products, pharmaceuticals, and cosmetics.

  8. The In Vitro Antioxidant Activity and Inhibition of Intracellular Reactive Oxygen Species of Sweet Potato Leaf Polyphenols

    Science.gov (United States)

    Sun, Hongnan; Mu, Bona; Song, Zhen; Ma, Zhimin

    2018-01-01

    The in vitro antioxidant activity and inhibition of intracellular reactive oxygen species (ROS) of the total and individual phenolic compounds from Yuzi No. 7 sweet potato leaves were investigated in this study. Sweet potato leaf polyphenols possessed significantly higher antioxidant activity than ascorbic acid, tea polyphenols, and grape seed polyphenols. Among the individual phenolic compounds, caffeic acid showed the highest antioxidant activity, followed by monocaffeoylquinic acids and dicaffeoylquinic acids, while 3,4,5-tri-O-caffeoylquinic acid showed the lowest value. Sweet potato leaf polyphenols could significantly decrease the level of intracellular ROS in a dose-dependent manner. The order of the inhibiting effect of individual phenolic compounds on the intracellular ROS level was not in accordance with that of antioxidant activity, suggesting that there was no direct relationship between antioxidant activity and intracellular ROS-inhibiting effect. Sweet potato leaves could be a good source of biologically active polyphenols with multiple applications in the development of foods, health products, pharmaceuticals, and cosmetics. PMID:29643978

  9. Effect of polyphenol oxidase (PPO and air treatments on total phenol and tannin content of cocoa nibs

    Directory of Open Access Journals (Sweden)

    Brito Edy Sousa de

    2002-01-01

    Full Text Available Cocoa flavour is greatly influenced by polyphenols. These compounds undergo a series of transformations during cocoa processing leading to the characteristic cocoa flavour. The use of exogenous polyphenol oxidase (PPO proved to be useful to reduce polyphenol content in cocoa nibs. The effect of a PPO associated or not with air over total phenol and tannin content was evaluated. Cocoa nibs were autoclaved and treated with a PPO or water in the absence or presence of an air flow for 0.5, 1, 2 and 3 hours. Total phenol content was reduced in PPO or water treatments, but when associated with air there was an increase in phenol content. Tannin content was reduced only by the treatment with water and air.

  10. Isolation of a polyphenol oxidase (PPO) cDNA from artichoke and expression analysis in wounded artichoke heads.

    Science.gov (United States)

    Quarta, Angela; Mita, Giovanni; Durante, Miriana; Arlorio, Marco; De Paolis, Angelo

    2013-07-01

    The polyphenol oxidase (PPO) enzyme, which can catalyze the oxidation of phenolics to quinones, has been reported to be involved in undesirable browning in many plant foods. This phenomenon is particularly severe in artichoke heads wounded during the manufacturing process. A full-length cDNA encoding for a putative polyphenol oxidase (designated as CsPPO) along with a 1432 bp sequence upstream of the starting ATG codon was characterized for the first time from [Cynara cardunculus var. scolymus (L.) Fiori]. The 1764 bp CsPPO sequence encodes a putative protein of 587 amino acids with a calculated molecular mass of 65,327 Da and an isoelectric point of 5.50. Analysis of the promoter region revealed the presence of cis-acting elements, some of which are putatively involved in the response to light and wounds. Expression analysis of the gene in wounded capitula indicated that CsPPO was significantly induced after 48 h, even though the browning process had started earlier. This suggests that the early browning event observed in artichoke heads was not directly related to de novo mRNA synthesis. Finally, we provide the complete gene sequence encoding for polyphenol oxidase and the upstream regulative region in artichoke. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  11. Purification and characterization of polyphenol oxidase from jackfruit ( Artocarpus heterophyllus ) bulbs.

    Science.gov (United States)

    Tao, Yi-Ming; Yao, Le-Yi; Qin, Qiu-Yan; Shen, Wang

    2013-12-26

    Polyphenol oxidase (PPO) from jackfruit bulb was purified through acetone precipitation, ion-exchange column, and gel filtration column. PPO was a dimer with the molecular weight of 130 kDa determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration. The Km was 8.3 and 18.2 mM using catechol and 4-methylcatechol as substrates, respectively. The optimum pH was 7.0 (catechol as the substrate) or 6.5 (4-methylcatechol as the substrate). The optimum temperature was 8 °C. The enzyme was stable below 40 °C. The activation energy (Ea) of heat inactivation was estimated to be 103.30 kJ/mol. The PPO activity was activated by Mn(2+), SDS, Tween-20, Triton X-100, citric acid, and malic acid but inhibited by K(+), Zn(2+), Mg(2+), Ca(2+), Ba(2+), cetyl trimethyl ammonium bromide (CTAB), kojic acid, tropolone, glutathione (GSH), cysteine (Cys), and ascorbic acid (AA). Cys and AA were effective to reduce browning of jackfruit bulbs during the storage at 8 °C for 15 days.

  12. Effect of phenol on germination capacity and polyphenol oxidase, peroxidase and catalase activities in lettuce

    Directory of Open Access Journals (Sweden)

    Tadić Vojin

    2014-01-01

    Full Text Available In this study we examined the activities of polyphenol oxidase (PPO and antioxidant enzymes, peroxidase (POX and catalase (CAT during lettuce seed germination at different concentrations of phenol. Out of eleven varieties of lettuce, four were chosen according to their germination tolerance to phenol as follows: plants exhibiting high (Ljubljanska ledenka - LJL and Nansen - N and low toleranace (Little Gem - LG and Majska kraljica - MK. A decrease in germination efficiency after exposure to LD50 of phenol was determined for these four varieties. The effects of phenol treatment on POX, CAT and PPO activities were determined after 4, 5, 6, 7 and 8 days of growth at LD50 concentrations. A trend of increased peroxidase activity was observed in seeds grown on LD50 of phenol compared to control seeds. A significant increase in CAT activity was observed at the beginning of treatment for MK, LG and N in seeds grown on phenol as well as in control seeds. A trend of increased PPO activity was observed in all control seeds. We also investigated the affinity of PPO for two different substrates that were used for the determination of enzyme activity. Our results show that LJL and N are the varieties most tolerant to growth on phenol. Here we report on the activities of their antioxidant enzymes and PPO during seed germination. [Projekat Ministarstva nauke Republike Srbije, br. ON173017

  13. Purification and Characterization of Polyphenol Oxidase, Peroxidase and Lipoxygenase from Freshly Cut Lettuce (L. sativa

    Directory of Open Access Journals (Sweden)

    Vural Gökmen

    2011-01-01

    Full Text Available Enzymatic reactions taking place in minimally processed vegetables are considered as a major problem, because they adversely affect sensorial and nutritional quality. Polyphenol oxidase (PPO, peroxidase (POD and lipoxygenase (LOX from lettuce were purified on a column packed with positively charged diethylaminoethyl (DEAE cellulose by applying pH gradient elution from pH=4.0 to 9.0. The main purified fractions (PPO1 and PPO4, POD1 and POD2, LOX1 and LOX2 were characterized for enzyme concentration-reaction rate relationship, thermal stability, pH activity and kinetic parameters. Kinetic properties of each isoform were considerably different. Cysteine was found as the most effective inhibitor of both fractions of PPO. Kinetic parameters of lettuce POD were presented using guaiacol at various H2O2 concentrations. β-carotene directly influences lettuce LOX in the reaction medium available for the catalytic conversion of linoleic acid into hydroperoxides. Ascorbic and oxalic acids appear as effective PPO inhibitors, protecting phenolic compounds against oxidation in lettuce. Understanding the characteristics of deteriorative enzymes becomes important to maintain suitable conditions for fresh-like quality of lettuce. The results can be useful to keep the nutritional quality of minimally processed lettuce during shelf-life.

  14. Partial purification and characterization of polyphenol oxidase from banana (Musa sapientum L.) peel.

    Science.gov (United States)

    Yang, C P; Fujita, S; Kohno, K; Kusubayashi, A; Ashrafuzzaman, M; Hayashi, N

    2001-03-01

    Polyphenol oxidase (EC 1.10.3.1, o-diphenol: oxygen oxidoreductase, PPO) of banana (Musa sapientum L.) peel was partially purified about 460-fold with a recovery of 2.2% using dopamine as substrate. The enzyme showed a single peak on Toyopearl HW55-S chromatography. However, two bands were detected by staining with Coomassie brilliant blue on PAGE: one was very clear, and the other was faint. Molecular weight for purified PPO was estimated to be about 41 000 by gel filtration. The enzyme quickly oxidized dopamine, and its Km value (Michaelis constant) for dopamine was 3.9 mM. Optimum pH was 6.5 and the PPO activity was quite stable in the range of pH 5-11 for 48 h. The enzyme had an optimum temperature at 30 degrees C and was stable up to 60 degrees C after heat treatment for 30 min. The enzyme activity was strongly inhibited by sodium diethyldithiocarbamate, potassium cyanide, L-ascorbic acid, and cysteine at 1 mM. Under a low buffer capacity, the enzyme was also strongly inhibited by citric acid and acetic acid at 10 mM.

  15. Purification and characterization of polyphenol oxidase from banana (Musa sapientum L.) pulp.

    Science.gov (United States)

    Yang, C P; Fujita, S; Ashrafuzzaman, M; Nakamura, N; Hayashi, N

    2000-07-01

    Polyphenol oxidase (EC 1.10.3.1, PPO) in the pulp of banana (Musa sapientum L.) was purified to 636-fold with a recovery of 3.0%, using dopamine as substrate. The purified enzyme exhibited a clear single band on polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate (SDS)-PAGE. The molecular weight of the enzyme was estimated to be about 41000 and 42000 by gel filtration and SDS-PAGE, respectively. The enzyme quickly oxidized dopamine, and its K(m) value for dopamine was 2.8 mM. The optimum pH was at 6.5, and the enzyme activity was stable in the range of pH 5-11 at 5 degrees C for 48 h. The enzyme had an optimum temperature of 30 degrees C and was stable even after a heat treatment at 70 degrees C for 30 min. The enzyme activity was completely inhibited by L-ascorbic acid, cysteine, sodium diethyldithiocarbamate, and potassium cyanide. Under a low buffer capacity, the enzyme was also strongly inhibited by citric acid and acetic acid at 10 mM.

  16. Polyphenol oxidase activity and antioxidant properties of Yomra apple (Malus communis L.) from Turkey.

    Science.gov (United States)

    Can, Zehra; Dincer, Barbaros; Sahin, Huseyin; Baltas, Nimet; Yildiz, Oktay; Kolayli, Sevgi

    2014-12-01

    In this study, firstly, antioxidant and polyphenol oxidase (PPO) properties of Yomra apple were investigated. Seventeen phenolic constituents were measured by reverse phase-high-performance liquid chromatography (RP-HPLC). Total phenolic compounds (TPCs), ferric reducing antioxidant power (FRAP) and 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activities were performed to measure antioxidant capacity. Some kinetic parameters (Km, Vmax), and inhibition behaviors against five different substrates were measured in the crude extract. Catechin and chlorogenic acid were found as the major components in the methanolic extract, while ferulic acid, caffeic acid, p-hydroxybenzoic acid, quercetin and p-coumaric acid were small quantities. Km values ranged from 0.70 to 10.10 mM in the substrates, and also 3-(4-hydroxyphenyl) propanoic acid (HPPA) and L-DOPA showed the highest affinity. The inhibition constant of Ki were ranged from 0.05 to 14.90 mM against sodium metabisulphite, ascorbic acid, sodium azide and benzoic acid, while ascorbic acid and sodium metabisulphite were the best inhibitors.

  17. Purification and partial biochemical characterization of polyphenol oxidase from mango (Mangifera indica cv. Manila).

    Science.gov (United States)

    Palma-Orozco, Gisela; Marrufo-Hernández, Norma A; Sampedro, José G; Nájera, Hugo

    2014-10-08

    Polyphenol oxidase (PPO) is an enzyme widely distributed in the plant kingdom that has been detected in most fruits and vegetables. PPO was extracted and purified from Manila mango (Mangifera indica), and its biochemical properties were studied. PPO was purified 216-fold by hydrophobic interaction and ion exchange chromatography. PPO was purified to homogeneity, and the estimated PPO molecular weight (MW) by SDS-PAGE was ≈31.5 kDa. However, a MW of 65 kDa was determined by gel filtration, indicating a dimeric structure for the native PPO. The isolated PPO showed the highest affinity to pyrogallol (Km = 2.77 mM) followed by 4-methylcatechol (Km = 3.14 mM) and catechol (Km = 15.14 mM). The optimum pH for activity was 6.0. PPO was stable in the temperature range of 20-70 °C. PPO activity was completely inhibited by tropolone, ascorbic acid, sodium metabisulfite, and kojic acid at 0.1 mM.

  18. Potential Use of Apple Polyphenol Oxidase for Bioremediation of Phenolic Contaminants

    Directory of Open Access Journals (Sweden)

    Anita Šalić

    2018-04-01

    Full Text Available Phenolic compounds, such as catechol, are released into the environment from a variety of industrial sources and they present a serious ecosystem burden. This work examined the possibility of using partially purified apple polyphenol oxidase (PPO for bioremediation of phenolic contaminants. In order to optimize process conditions, the optimal pH and temperature for PPO activity were determined, while PPO affinity toward various phenols, as well as the effect of some salts and organic solvents which can be found in wastewaters, was used to confirm applicability of PPO in wastewater treatment. It was found that partially purified apple PPO shows maximal activity at pH 6.8 and 25 °C, but exhibits more than 85 % of its maximal activity in pH range from 5 to 8, and more than 90 % of activity in temperature range from 10 to 50 °C. PPO showed high affinity for various diphenols, but lack of affinity toward monophenols. Sodium tetraborate decahydrate moderately inhibited PPO activity, while exposure of PPO to the presence of organic solvents (φ = 5 % caused 40 % loss in its activity. Catechol oxidation by PPO performed for just 5 min in a batch reactor at optimal process conditions resulted in 25 % conversion. Based on obtained data, it seems that partially purified apple PPO has reasonable potential in wastewater treatment.

  19. Characterization of polyphenol oxidase from Cape gooseberry (Physalis peruviana L.) fruit.

    Science.gov (United States)

    Bravo, Karent; Osorio, Edison

    2016-04-15

    Cape gooseberry (Physalis peruviana) is an exotic fruit highly valued, however it is a very rich source of polyphenol oxidase (PPO). In this study, Cape gooseberry PPO was isolated and biochemically characterized. The enzyme was extracted and purified using acetone and aqueous two-phase systems. The data indicated that PPO had the highest substrate affinity for chlorogenic acid, 4-methylcatechol and catechol. Chlorogenic acid was the most suitable substrate (Km=0.56±0.07 mM and Vmax=53.15±2.03 UPPO mL(-1) min(-1)). The optimal pH values were 5.5 for catechol and 4-methylcatechol and 5.0 for chlorogenic acid. Optimal temperatures were 40°C for catechol, 25°C for 4-methylcatechol and 20°C for chlorogenic acid. In inhibition tests, the most potent inhibitor was found to be ascorbic acid followed by L-cysteine and quercetin. This study shows possible treatments that can be implemented during the processing of Cape gooseberry fruits to prevent browning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Cloning, sequencing, purification, and crystal structure of Grenache (Vitis vinifera) polyphenol oxidase.

    Science.gov (United States)

    Virador, Victoria M; Reyes Grajeda, Juan P; Blanco-Labra, Alejandro; Mendiola-Olaya, Elizabeth; Smith, Gary M; Moreno, Abel; Whitaker, John R

    2010-01-27

    The full-length cDNA sequence (P93622_VITVI) of polyphenol oxidase (PPO) cDNA from grape Vitis vinifera L., cv Grenache, was found to encode a translated protein of 607 amino acids with an expected molecular weight of ca. 67 kDa and a predicted pI of 6.83. The translated amino acid sequence was 99%, identical to that of a white grape berry PPO (1) (5 out of 607 amino acid potential sequence differences). The protein was purified from Grenache grape berries by using traditional methods, and it was crystallized with ammonium acetate by the hanging-drop vapor diffusion method. The crystals were orthorhombic, space group C222(1). The structure was obtained at 2.2 A resolution using synchrotron radiation using the 39 kDa isozyme of sweet potato PPO (PDB code: 1BT1 ) as a phase donor. The basic symmetry of the cell parameters (a, b, and c and alpha, beta, and gamma) as well as in the number of asymmetric units in the unit cell of the crystals of PPO, differed between the two proteins. The structures of the two enzymes are quite similar in overall fold, the location of the helix bundles at the core, and the active site in which three histidines bind each of the two catalytic copper ions, and one of the histidines is engaged in a thioether linkage with a cysteine residue. The possibility that the formation of the Cys-His thioether linkage constitutes the activation step is proposed. No evidence of phosphorylation or glycoslyation was found in the electron density map. The mass of the crystallized protein appears to be only 38.4 kDa, and the processing that occurs in the grape berry that leads to this smaller size is discussed.

  1. Polyphenol Oxidase Induction in Lulo Fruits (Solanum quitoense Infected by Colletotrichum acutatum

    Directory of Open Access Journals (Sweden)

    Obradith Caicedo O.

    2007-08-01

    Full Text Available Polyphenol oxidase (PFO activity induction was evaluated in lulo fruits to determine the role of this enzyme in resistance responses towards the pathogen Colletotrichum acutatum which causes anthracnose disease. We studied the experimental conditions to obtain the enzyme, using lulo peel, and found that extraction with phosphates buffer 100 mM pH 7, 1% SDS y 1% PVPP showed higher activities. The adequate parameters for activity measurement was also evaluated and established as cathecol 40 mM, pH 7,0, 23 °C and 30 µL of extract. Then, we performed an in vivo assay using lulo fruits in three maturity stages, green, semimature and mature, which were inoculated with the fungus or with sterile water. Enzymatic induction of this protein was studied at nine postinoculation times, and it was found that the induction was differential according to the time, the maturity stage, and as consequence of pathogen presence. The PFO activity increased in green fruits at 48, 96 y 144 (hours postinoculation (hpi, and in mature lulos for the majority of times studied, with the most significant induction response at this stage. In semimature lulo, the induction was observed only at 72 and 144 hpi. The highest nominal value of activity was found in green fruits. Fruits responded to incision with enzyme activation. The increase in the activity of the enzyme was faster in the fruits with the minor anthracnose symptoms than the ones that were more affected. Therefore, it is possible to postulate a positive relation between PFO induction and tolerance to anthracnose symptoms.

  2. Purification and biochemical characterization of ionically unbound polyphenol oxidase from Musa paradisiaca leaf.

    Science.gov (United States)

    Diwakar, Sanjeev Kumar; Mishra, Sarad Kumar

    2011-01-01

    An ionically unbound and thermostable polyphenol oxidase (PPO) was extracted from the leaf of Musa paradisiaca. The enzyme was purified 2.54-fold with a total yield of 9.5% by ammonium sulfate precipitation followed by Sephadex G-100 gel filtration chromatography. The purified enzyme exhibited a clear single band on native polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate (SDS) PAGE. It was found to be monomeric protein with molecular mass of about 40 kD. The zymographic study using crude extract as enzyme source showed a very clear band around 40 kD and a faint band at around 15 kD, which might be isozymes. The enzyme was optimally active at pH 7.0 and 50°C temperature. The enzyme was active in wide range of pH (4.0-9.0) and temperature (30-90°C). From the thermal inactivation studies in the range 60-75°C, the half-life (t(1/2)) values of the enzyme ranged from 17 to 77 min. The inactivation energy (Ea) value of PPO was estimated to be 91.3 kJ mol(-1). It showed higher specificity with catechol (K(m) = 8 mM) as compared to 4-methylcatechol (K(m) = 10 mM). Among metal ions and reagents tested, Cu(2+), Fe(2+), Hg(2+), Mn(2+), Ni(2+), protocatechuic acid, and ferrulic acid enhanced the enzyme activity, while K(+), Na(+), Co(2+), kojic acid, ascorbic acid, ethylenediamine tetraacetic acid (EDTA), sodium azide, β-mercaptoethanol, and L-cysteine inhibited the activity of the enzyme.

  3. [Spectral analysis of polyphenol oxidase (PPO) and lipoxygenase (LOX) treated by pulsed electric field].

    Science.gov (United States)

    Luo, Wei; Zhang, Ruo-Bing; Chen, Jie; Wang, Li-Ming; Guan, Zhi-Cheng; Jia, Zhi-Dong

    2009-08-01

    Inactivation effect of pulsed electric field (PEF) on polyphenol oxidase (PPO) and lipoxygenase (LOX) was investigated using a laboratory PEF system with a coaxial treatment chamber. Circular dichroism (CD) and fluorescence analysis were used to study the conformation change of the protein. The experimental results show that PPO and LOX can be effectively inactivated by the PEF treatment. Inactivation effect of PPO and LOX increases with the increase in the applied electric strength and the treatment time. Activity of PPO and LOX can be reduced by 60.3% and 21.7% at 20 kV x cm(-1) after being treated for 320 micros respectively. The decrease of the negative peaks (208 and 215 nm in PPO spectra, 208 nm and 218 nm in LOX spectra) in CD spectra of PPO and LOX shows that PEF treatment caused a loss of alpha-helix and increase in beta-sheet content, indicating that conformation changes occur in the secondary structure of PPO and LOX enzyme. This effect was strengthened as the applied electric field increased: alpha-helical content of PPO and LOX was 56% and 29% after being treated at 8 kV x cm(-1), however, when the electric field was increased up to 20 kV x cm(-1), alpha-helical content of PPO and LOX decreased to 21% and 16% respectively. The decrease rate of alpha-helix and increase rate of beta-sheet in PPO are higher than LOX, indicating that the second conformation of PPO is less resistant to PEF treatment than LOX. The fluorescence intensity of LOX increases after PEF treatment. At the same time, increasing the applied pulsed electric field increases the fluorescence intensity emitted. Fluorescence measurements confirm that tertiary conformation changes occur in the local structure of LOX. However the possible mechanism of the conformation change induced by the PEF treatment is beyond the scope of the present investigation.

  4. Protection by deferoxamine from endothelial injury: A possible link with inhibition of intracellular xanthine oxidase

    International Nuclear Information System (INIS)

    Rinaldo, J.E.; Gorry, M.

    1990-01-01

    Hydroxyl radical scavengers and xanthine oxidase inhibitors protect cultured bovine pulmonary endothelial cells (BPAEC) from lytic injury by the endotoxin lipopolysaccharide (LPS). We hypothesized that exposure of BPAEC to cytotoxic concentrations of LPS activated intracellular xanthine oxidase, and that intracellular iron-dependent hydroxyl radical formation (a Fenton reaction) ensued, resulting in cell lysis. To test this, the protective effects of deferoxamine against H2O2 and LPS-induced cytotoxicity to BPAEC was assessed by 51Cr release. Preincubation with 0.4 mM deferoxamine conferred 67 +/- 15% (mean +/- SE) protection from LPS-induced cytotoxicity but 48 h of preincubation were required to induce significant protection. Significant protection form a classical Fenton reaction model, injury by 50 microM H2O2, could be induced by a 1-h preincubation with a 0.4 mM deferoxamine. The dissociated time course suggested that deferoxamine might work by different mechanisms in these models. The effects of LPS and deferoxamine on BPAEC-associated xanthine oxidase (XO) and xanthine dehydrogenase (XD) activity were assessed using a spectrofluorophotometric measurement of the conversion of pterin to isoxanthopterin. BPAEC had 106 +/- 7 microU/mg XD+XO activity; XO activity constituted 48 +/- 1% of total XO+XD activity. LPS at a cytotoxic concentration did not alter XO, XD, or percent XO. Deferoxamine had striking proportional inhibitory effects on XO and XD in intact cells. XO+XD activity fell to 6 +/- 1% of control levels during a 48-h exposure of BPAEC to deferoxamine. Deferoxamine did not inhibit XO+XD ex vivo

  5. The polyphenol oxidase gene family in land plants: Lineage-specific duplication and expansion

    Directory of Open Access Journals (Sweden)

    Tran Lan T

    2012-08-01

    Full Text Available Abstract Background Plant polyphenol oxidases (PPOs are enzymes that typically use molecular oxygen to oxidize ortho-diphenols to ortho-quinones. These commonly cause browning reactions following tissue damage, and may be important in plant defense. Some PPOs function as hydroxylases or in cross-linking reactions, but in most plants their physiological roles are not known. To better understand the importance of PPOs in the plant kingdom, we surveyed PPO gene families in 25 sequenced genomes from chlorophytes, bryophytes, lycophytes, and flowering plants. The PPO genes were then analyzed in silico for gene structure, phylogenetic relationships, and targeting signals. Results Many previously uncharacterized PPO genes were uncovered. The moss, Physcomitrella patens, contained 13 PPO genes and Selaginella moellendorffii (spike moss and Glycine max (soybean each had 11 genes. Populus trichocarpa (poplar contained a highly diversified gene family with 11 PPO genes, but several flowering plants had only a single PPO gene. By contrast, no PPO-like sequences were identified in several chlorophyte (green algae genomes or Arabidopsis (A. lyrata and A. thaliana. We found that many PPOs contained one or two introns often near the 3’ terminus. Furthermore, N-terminal amino acid sequence analysis using ChloroP and TargetP 1.1 predicted that several putative PPOs are synthesized via the secretory pathway, a unique finding as most PPOs are predicted to be chloroplast proteins. Phylogenetic reconstruction of these sequences revealed that large PPO gene repertoires in some species are mostly a consequence of independent bursts of gene duplication, while the lineage leading to Arabidopsis must have lost all PPO genes. Conclusion Our survey identified PPOs in gene families of varying sizes in all land plants except in the genus Arabidopsis. While we found variation in intron numbers and positions, overall PPO gene structure is congruent with the phylogenetic

  6. Characterization and purification of polyphenol oxidase from artichoke (Cynara scolymus L.).

    Science.gov (United States)

    Dogan, Serap; Turan, Yusuf; Ertürk, Hatibe; Arslan, Oktay

    2005-02-09

    In this study, the polyphenol oxidase (PPO) of artichoke (Cynara scolymus L.) was first purified by a combination of (NH(4))(2)SO(4) precipitation, dialysis, and a Sepharose 4B-L-tyrosine-p-aminobenzoic acid affinity column. At the end of purification, 43-fold purification was achieved. The purified enzyme migrated as a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Polyacrylamide gel electrophoresis indicated that PPO had a 57 kDa molecular mass. Second, the contents of total phenolic and protein of artichoke head extracts were determined. The total phenolic content of artichoke head was determined spectrophotometrically according to the Folin-Ciocalteu procedure and was found to be 425 mg 100 g(-1) on a fresh weight basis. Protein content was determined according to Bradford method. Third, the effects of substrate specificity, pH, temperature, and heat inactivation were investigated on the activity of PPO purified from artichoke. The enzyme showed activity to 4-methylcatechol, pyrogallol, catechol, and L-dopa. No activity was detected toward L-tyrosine, resorsinol, and p-cresol. According to V(max)/K(m) values, 4-methylcatechol (1393 EU min(-1) mM(-1)) was the best substrate, followed by pyrogallol (1220 EU min(-1) mM(-1)), catechol (697 EU min(-1) mM(-1)), and L-dopa (102 EU min(-1) mM(-1)). The optimum pH values for PPO were 5.0, 8.0, and 7.0 using 4-methylcatechol, pyrogallol, and catechol as substrate, respectively. It was found that optimum temperatures were dependent on the substrates studied. The enzyme activity decreased due to heat denaturation of the enzyme with increasing temperature and inactivation time for 4-methylcatechol and pyrogallol substrates. However, all inactivation experiments for catechol showed that the activity of artichoke PPO increased with mild heating, reached a maximum, and then decreased with time. Finally, inhibition of artichoke PPO was investigated with inhibitors such as L-cysteine, EDTA, ascorbic

  7. Expression analysis of polyphenol oxidase isozymes by active staining method and tissue browning of head lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Noda, Takahiro; Iimure, Kazuhiko; Okamoto, Shunsuke; Saito, Akira

    2017-08-01

    Browning of plant tissue is generally considered attributable to enzymatic oxidation by polyphenol oxidase (PPO). Electrophoresis followed by activity staining has been used as an effective procedure to visually detect and isolate isozymes; however, it has not been applied for examination of various PPO isozymes in lettuce. Our study demonstrated that different lettuce PPO isozymes could be detected at different pH in active staining, and multiple isozymes were detected only under alkaline conditions. As a result, we concluded that activity staining with approximately pH 8 enabled to detect various PPO isozymes in lettuce. By expression analysis of the PPO isozymes after wounding, PPO isozymes that correlated with time-course of tissue browning were detected. The wound-induced PPO may play a key role in enzymatic browning.

  8. Promising perspectives for ruminal protection of polyunsaturated fatty acids through polyphenol-oxidase-mediated crosslinking of interfacial protein in emulsions.

    Science.gov (United States)

    De Neve, N; Vlaeminck, B; Gadeyne, F; Claeys, E; Van der Meeren, P; Fievez, V

    2018-03-16

    Previously, polyunsaturated fatty acids (PUFA) from linseed oil were effectively protected (>80%) against biohydrogenation through polyphenol-oxidase-mediated protein crosslinking of an emulsion, prepared with polyphenol oxidase (PPO) extract from potato tuber peelings. However, until now, emulsions of only 2 wt% oil have been successfully protected, which implies serious limitations both from a research perspective (e.g. in vivo trials) as well as for further upscaling toward practical applications. Therefore, the aim of this study was to increase the oil/PPO ratio. In the original protocol, the PPO extract served both an emulsifying function as well as a crosslinking function. Here, it was first evaluated whether alternative protein sources could replace the emulsifying function of the PPO extract, with addition of PPO extract and 4-methylcatechol (4MC) to induce crosslinking after emulsion preparation. This approach was then further used to evaluate protection of emulsions with higher oil content. Five candidate emulsifiers (soy glycinin, gelatin, whey protein isolate (WPI), bovine serum albumin and sodium caseinate) were used to prepare 10 wt% oil emulsions, which were diluted five times (w/w) with PPO extract (experiment 1). As a positive control, 2 wt% oil emulsions were prepared directly with PPO extract according to the original protocol. Further, emulsions of 2, 4, 6, 8 and 10 wt% oil were prepared, with 80 wt% PPO extract (experiment 2), or with 90, 80, 70, 60 and 50 wt% PPO extract, respectively (experiment 3) starting from WPI-stabilized emulsions. Enzymatic crosslinking was induced by 24-h incubation with 4MC. Ruminal protection efficiency was evaluated by 24-h in vitro batch simulation of the rumen metabolism. In experiment 1, protection efficiencies were equal or higher than the control (85.5% to 92.5% v. 81.3%). In both experiments 2 and 3, high protection efficiencies (>80%) were achieved, except for emulsions containing 10 wt% oil emulsions

  9. Tea polyphenols alleviate high fat and high glucose-induced endothelial hyperpermeability by attenuating ROS production via NADPH oxidase pathway.

    Science.gov (United States)

    Zuo, Xuezhi; Tian, Chong; Zhao, Nana; Ren, Weiye; Meng, Yi; Jin, Xin; Zhang, Ying; Ding, Shibin; Ying, Chenjiang; Ye, Xiaolei

    2014-03-02

    Hyperglycemia-induced endothelial hyperpermeability is crucial to cardiovascular disorders and macro-vascular complications in diabetes mellitus. The objective of this study is to investigate the effects of green tea polyphenols (GTPs) on endothelial hyperpermeability and the role of nicotinamide adenine dinucleotide phosphate (NADPH) pathway. Male Wistar rats fed on a high fat diet (HF) were treated with GTPs (0, 0.8, 1.6, 3.2 g/L in drinking water) for 26 weeks. Bovine aortic endothelial cells (BAECs) were treated with high glucose (HG, 33 mmol/L) and GTPs (0.0, 0.4, or 4 μg/mL) for 24 hours in vitro. The endothelial permeabilities in rat aorta and monolayer BAECs were measured by Evans blue injection method and efflux of fluorescein isothiocyanate (FITC)-dextran, respectively. The reactive oxygen species (ROS) levels in rat aorta and monolayer BAECs were measured by dihydroethidium (DHE) and 2', 7'-dichloro-fluorescein diacetate (DCFH-DA) fluorescent probe, respectively. Protein levels of NADPH oxidase subunits were determined by Western-blot. HF diet-fed increased the endothelial permeability and ROS levels in rat aorta while HG treatments increased the endothelial permeability and ROS levels in cultured BAECs. Co-treatment with GTPs alleviated those changes both in vivo and in vitro. In in vitro studies, GTPs treatments protected against the HG-induced over-expressions of p22phox and p67phox. Diphenylene iodonium chloride (DPI), an inhibitor of NADPH oxidase, alleviated the hyperpermeability induced by HG. GTPs could alleviate endothelial hyperpermeabilities in HF diet-fed rat aorta and in HG treated BAECs. The decrease of ROS production resulting from down-regulation of NADPH oxidase contributed to the alleviation of endothelial hyperpermeability.

  10. Thermal and pH stabilities of partially purified polyphenol oxidase ...

    African Journals Online (AJOL)

    Dr. Paul Chidoka Chikezie

    2012-07-30

    Jul 30, 2012 ... indices of the two PPO extracts is summarized in Table. 1. At the end of the .... activity near neutral pH values (Jime´nez-Atie´nzar et al.,. 2004; Dogan and Dogan, 2004). ..... oxidase from white cherry fruit (Starks gold). GIDA.

  11. Preparation of biosensors by immobilization of polyphenol oxidase in conducting copolymers and their use in determination of phenolic compounds in red wine.

    Science.gov (United States)

    Böyükbayram, A Elif; Kiralp, Senem; Toppare, Levent; Yağci, Yusuf

    2006-10-01

    Electrochemically produced graft copolymers of thiophene capped polytetrahydofuran (TPTHF1 and TPTHF2) and pyrrole were achieved by constant potential electrolysis using sodium dodecylsulfate (SDS) as the supporting electrolyte. Characterizations were based on Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Electrical conductivities were measured by the four-probe technique. Novel biosensors for phenolic compounds were constructed by immobilizing polyphenol oxidase (PPO) into conducting copolymers prepared by electropolymerization of pyrrole with thiophene capped polytetrahydrofuran. Kinetic parameters, maximum reaction rate (V(max)) and Michaelis-Menten constant (K(m)) and optimum conditions regarding temperature and pH were determined for the immobilized enzyme. Operational stability and shelf-life of the enzyme electrodes were investigated. Enzyme electrodes of polyphenol oxidase were used to determine the amount of phenolic compounds in two brands of Turkish red wines and found very useful owing to their high kinetic parameters and wide pH working range.

  12. Characterization of the polyphenol oxidase gene family reveals a novel microRNA involved in posttranscriptional regulation of PPOs in Salvia miltiorrhiza

    OpenAIRE

    Li, Caili; Li, Dongqiao; Li, Jiang; Shao, Fenjuan; Lu, Shanfa

    2017-01-01

    Salvia miltiorrhiza is a well-known material of traditional Chinese medicine. Understanding the regulatory mechanisms of phenolic acid biosynthesis and metabolism are important for S. miltiorrhiza quality improvement. We report here that S. miltiorrhiza contains 19 polyphenol oxidases (PPOs), forming the largest PPO gene family in plant species to our knowledge. Analysis of gene structures and sequence features revealed the conservation and divergence of SmPPOs. SmPPOs were differentially exp...

  13. Removal of bisphenol derivatives through quinone oxidation by polyphenol oxidase and subsequent quinone adsorption on chitosan in the heterogeneous system.

    Science.gov (United States)

    Kimura, Yuji; Takahashi, Ayumi; Kashiwada, Ayumi; Yamada, Kazunori

    2015-01-01

    In this study, the combined use of a biopolymer chitosan and an oxidoreductase polyphenol oxidase (PPO) was systematically investigated for the removal of bisphenol derivatives from aqueous medium. The process parameters, such as the pH value, temperature, and PPO concentration, were estimated to conduct the enzymatic quinone oxidation of bisphenol derivatives by as little enzyme as possible. Bisphenol derivatives effectively underwent PPO-catalysed quinone oxidation without H2O2 unlike other oxidoreductases, such as peroxidase and tyrosinase, and the optimum conditions were determined to be pH 7.0 and 40°C for bisphenol B, bisphenol E, bisphenol O, and bisphenol Z; pH 7.0 and 30°C for bisphenol C and bisphenol F; and pH 8.0 and 40°C for bisphenol T. They were completely removed through adsorption of enzymatically generated quinone derivatives on chitosan beads or chitosan powders. Quinone adsorption on chitosan beads or chitosan powders in the heterogeneous system was found to be a more effective procedure than generation of aggregates in the homogeneous system with chitosan solution. The removal time was shortened by increasing the amount of chitosan beads or decreasing the size of the chitosan powders.

  14. Perennial peanut (Arachis glabrata Benth.) contains polyphenol oxidase (PPO) and PPO substrates that can reduce post-harvest proteolysis.

    Science.gov (United States)

    Sullivan, Michael L; Foster, Jamie L

    2013-08-15

    Studies of perennial peanut (Arachis glabrata Benth.) suggest its hay and haylage have greater levels of rumen undegraded protein (RUP) than other legume forages such as alfalfa (Medicago sativa L.). Greater RUP can result in more efficient nitrogen utilization by ruminant animals with positive economic and environmental effects. We sought to determine whether, like red clover (Trifolium pretense L.), perennial peanut contains polyphenol oxidase (PPO) and PPO substrates that might be responsible for increased RUP. Perennial peanut extracts contain immunologically detectible PPO protein and high levels of PPO activity (>100 nkatal mg(-1) protein). Addition of caffeic acid (PPO substrate) to perennial peanut extracts depleted of endogenous substrates reduced proteolysis by 90%. Addition of phenolics prepared from perennial peanut leaves to extracts of either transgenic PPO-expressing or control (non-expressing) alfalfa showed peanut phenolics could reduce proteolysis >70% in a PPO-dependent manner. Two abundant likely PPO substrates are present in perennial peanut leaves including caftaric acid. Perennial peanut contains PPO and PPO substrates that together are capable of inhibiting post-harvest proteolysis, suggesting a possible mechanism for increased RUP in this forage. Research related to optimizing the PPO system in other forage crops will likely be applicable to perennial peanut. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  15. Effects of gamma irradiation on the radiation-resistant bacteria and polyphenol oxidase activity in fresh kale juice

    International Nuclear Information System (INIS)

    Kim, Dongho; Song, Hyunpa; Lim, Sangyong; Yun, Hyejeong; Chung, Jinwoo

    2007-01-01

    Gamma radiation was performed to prolong the shelf life of natural kale juice. The total aerobic bacteria in fresh kale juice, prepared by a general kitchen process, was detected in the range of 10 6 cfu/ml, and about 10 2 cfu/ml of the bacteria survived in the juice in spite of gamma irradiation treatment with a dose of 5 kGy. Two typical radiation-resistant bacteria, Bacillus megaterium and Exiguobacterium acetylicum were isolated and identified from the 5 kGy-irradiated kale juices. The D 10 values of the vegetative cell and endospore of the B. megaterium in peptone water were 0.63±0.05 and 1.52±0.05 kGy, respectively. The D 10 value of the E. acetylicum was calculated as 0.65±0.06 kGy. In the inoculation test, the growth of the surviving B. megaterium and E. acetylicum in the 3-5 kGy-irradiated kale juice retarded and/or decreased significantly during a 3 d post-irradiation storage period. However, there were no significant differences in the residual polyphenol oxidase activity and browning index between the nonirradiated control and the gamma irradiated kale juice during a post-irradiation period

  16. Effects of gamma irradiation on the radiation-resistant bacteria and polyphenol oxidase activity in fresh kale juice

    Science.gov (United States)

    Kim, Dongho; Song, Hyunpa; Lim, Sangyong; Yun, Hyejeong; Chung, Jinwoo

    2007-07-01

    Gamma radiation was performed to prolong the shelf life of natural kale juice. The total aerobic bacteria in fresh kale juice, prepared by a general kitchen process, was detected in the range of 10 6 cfu/ml, and about 10 2 cfu/ml of the bacteria survived in the juice in spite of gamma irradiation treatment with a dose of 5 kGy. Two typical radiation-resistant bacteria, Bacillus megaterium and Exiguobacterium acetylicum were isolated and identified from the 5 kGy-irradiated kale juices. The D10 values of the vegetative cell and endospore of the B. megaterium in peptone water were 0.63±0.05 and 1.52±0.05 kGy, respectively. The D10 value of the E. acetylicum was calculated as 0.65±0.06 kGy. In the inoculation test, the growth of the surviving B. megaterium and E. acetylicum in the 3-5 kGy-irradiated kale juice retarded and/or decreased significantly during a 3 d post-irradiation storage period. However, there were no significant differences in the residual polyphenol oxidase activity and browning index between the nonirradiated control and the gamma irradiated kale juice during a post-irradiation period.

  17. The effect of ultrasound on particle size, color, viscosity and polyphenol oxidase activity of diluted avocado puree.

    Science.gov (United States)

    Bi, Xiufang; Hemar, Yacine; Balaban, Murat O; Liao, Xiaojun

    2015-11-01

    The effect of ultrasound treatment on particle size, color, viscosity, polyphenol oxidase (PPO) activity and microstructure in diluted avocado puree was investigated. The treatments were carried out at 20 kHz (375 W/cm(2)) for 0-10 min. The surface mean diameter (D[3,2]) was reduced to 13.44 μm from an original value of 52.31 μm by ultrasound after 1 min. A higher L(∗) value, ΔE value and lower a(∗) value was observed in ultrasound treated samples. The avocado puree dilution followed pseudoplastic flow behavior, and the viscosity of diluted avocado puree (at 100 s(-1)) after ultrasound treatment for 1 min was 6.0 and 74.4 times higher than the control samples for dilution levels of 1:2 and 1:9, respectively. PPO activity greatly increased under all treatment conditions. A maximum increase of 25.1%, 36.9% and 187.8% in PPO activity was found in samples with dilution ratios of 1:2, 1:5 and 1:9, respectively. The increase in viscosity and measured PPO activity might be related to the decrease in particle size. The microscopy images further confirmed that ultrasound treatment induced disruption of avocado puree structure. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Intracellular lysyl oxidase: Effect of a specific inhibitor on nuclear mass in proliferating cells

    Energy Technology Data Exchange (ETDEWEB)

    Saad, Fawzy A. [Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopedics, Children' s Hospital Boston, 300 Longwood Avenue EN926, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States); Torres, Marie [Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopedics, Children' s Hospital Boston, 300 Longwood Avenue EN926, Boston, MA 02115 (United States); Wang, Hao [Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopedics, Children' s Hospital Boston, 300 Longwood Avenue EN926, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States); Graham, Lila, E-mail: lilagraham@cs.com [Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopedics, Children' s Hospital Boston, 300 Longwood Avenue EN926, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States)

    2010-06-11

    LOX, the principal enzyme involved in crosslinking of collagen, was the first of several lysyl oxidase isotypes to be characterized. Its active form was believed to be exclusively extracellular. Active LOX was later reported to be present in cell nuclei; its function there is unknown. LOX expression opposes the effect of mutationally activated Ras, which is present in about 30% of human cancers. The mechanism of LOX in countering the action of Ras is also unknown. In the present work, assessment of nuclear protein for possible effects of lysyl oxidase activity led to the discovery that proliferating cells dramatically increase their nuclear protein content when exposed to BAPN ({beta}-aminopropionitrile), a highly specific lysyl oxidase inhibitor that reportedly blocks LOX inhibition of Ras-induced oocyte maturation. In three cell types (PC12 cells, A7r5 smooth muscle cells, and NIH 3T3 fibroblasts), BAPN caused a 1.8-, 1.7-, and 2.1-fold increase in total nuclear protein per cell, respectively, affecting all major components in both nuclear matrix and chromatin fractions. Since nuclear size is correlated with proliferative status, enzyme activity restricting nuclear growth may be involved in the lysyl oxidase tumor suppressive effect. Evidence is also presented for the presence of apparent lysyl oxidase isotype(s) containing a highly conserved LOX active site sequence in the nuclei of PC12 cells, which do not manufacture extracellular lysyl oxidase substrates. Results reported here support the hypothesis that nuclear lysyl oxidase regulates nuclear growth, and thereby modulates cell proliferation.

  19. Crystallization and preliminary crystallographic analysis of latent, active and recombinantly expressed aurone synthase, a polyphenol oxidase, from Coreopsis grandiflora

    Energy Technology Data Exchange (ETDEWEB)

    Molitor, Christian; Mauracher, Stephan Gerhard; Rompel, Annette, E-mail: annette.rompel@univie.ac.at [Universität Wien, Althanstrasse 14, 1090 Wien (Austria)

    2015-05-22

    Latent and active aurone synthase purified from petals of C. grandiflora (cgAUS1) were crystallized. The crystal quality of recombinantly expressed latent cgAUS1 was significantly improved by co-crystallization with the polyoxotungstate Na{sub 6}[TeW{sub 6}O{sub 24}] within the liquid–liquid phase-separation zone. Aurone synthase (AUS), a member of a novel group of plant polyphenol oxidases (PPOs), catalyzes the oxidative conversion of chalcones to aurones. Two active cgAUS1 (41.6 kDa) forms that differed in the level of phosphorylation or sulfation as well as the latent precursor form (58.9 kDa) were purified from the petals of Coreopsis grandiflora. The differing active cgAUS1 forms and the latent cgAUS1 as well as recombinantly expressed latent cgAUS1 were crystallized, resulting in six different crystal forms. The active forms crystallized in space groups P2{sub 1}2{sub 1}2{sub 1} and P12{sub 1}1 and diffracted to ∼1.65 Å resolution. Co-crystallization of active cgAUS1 with 1,4-resorcinol led to crystals belonging to space group P3{sub 1}21. The crystals of latent cgAUS1 belonged to space group P12{sub 1}1 and diffracted to 2.50 Å resolution. Co-crystallization of recombinantly expressed pro-AUS with the hexatungstotellurate(VI) salt Na{sub 6}[TeW{sub 6}O{sub 24}] within the liquid–liquid phase separation zone significantly improved the quality of the crystals compared with crystals obtained without hexatungstotellurate(VI)

  20. Browning in Annona cherimola fruit: role of polyphenol oxidase and characterization of a coding sequence of the enzyme.

    Science.gov (United States)

    Prieto, Humberto; Utz, Daniella; Castro, Alvaro; Aguirre, Carlos; González-Agüero, Mauricio; Valdés, Héctor; Cifuentes, Nicolas; Defilippi, Bruno G; Zamora, Pablo; Zúñiga, Gustavo; Campos-Vargas, Reinaldo

    2007-10-31

    Cherimoya (Annona cherimola Mill.) fruit is an attractive candidate for food processing applications as fresh cut. However, along with its desirable delicate taste, cherimoya shows a marked susceptibility to browning. This condition is mainly attributed to polyphenol oxidase activity (PPO). A general lack of knowledge regarding PPO and its role in the oxidative loss of quality in processed cherimoya fruit requires a better understanding of the mechanisms involved. The work carried out included the cloning of a full-length cDNA, an analysis of its properties in the deduced amino sequence, and linkage of its mRNA levels with enzyme activity in mature and ripe fruits after wounding. The results showed one gene different at the nucleotide level when compared with previously reported genes, but a well-conserved protein, either in functional and in structural terms. Cherimoya PPO gene (Ac-ppo, GenBank DQ990911) showed to be present apparently in one copy of the genome, and its transcripts could be significantly detected in leaves and less abundantly in flowers and fruits. Analysis of wounded matured and ripened fruits revealed an inductive behavior for mRNA levels in the flesh of mature cherimoya after 16 h. Although the highest enzymatic activity was observed on rind, a consistent PPO activity was detected on flesh samples. A lack of correlation between PPO mRNA level and PPO activity was observed, especially in flesh tissue. This is probably due to the presence of monophenolic substrates inducing a lag period, enzyme inhibitors and/or diphenolic substrates causing suicide inactivation, and proenzyme or latent isoforms of PPO. To our knowledge this is the first report of a complete PPO sequence in cherimoya. Furthermore, the gene is highly divergent from known nucleotide sequences but shows a well conserved protein in terms of its function, deduced structure, and physiological role.

  1. Comparative investigation to see the efficacy of polyphenol oxidase inhibitors parallel to sulphite for control of enzymatic browning in guava juice

    International Nuclear Information System (INIS)

    Zai, M.N.K.A.

    2008-01-01

    Comparative study was conducted to determine the efficacy of polyphenol oxidase inhibitors to control browning in guava juice/concentrates parallel to sulfite. Although sulfites are highly effective to control the browning but these have shown adverse effect on health particularly to those who have pulmonary disorder like asthma. Filtration with useful filter aid and juicing agents are found to be helpful in removing browning residue particulates fractions to extend the shelf life of the juice. Non-enzymatic browning can be prevented by cold blanching. (author)

  2. Immunogold Labelling to Localize Polyphenol Oxidase (PPO) During Wilting of Red Clover Leaf Tissue and the Effect of Removing Cellular Matrices on PPO Protection of Glycerol-Based Lipid in the Rumen

    Science.gov (United States)

    The enzyme polyphenol oxidase (PPO) reduces the extent of proteolysis and lipolysis within red clover fed to ruminants. PPO catalyses the conversion of phenols to quinones which can react with nucleophilic cellular constituents (e.g. proteins), forming protein-phenol complexes that may reduce protei...

  3. Polyphenol oxidase activity from three sicilian artichoke [ Cynara cardunculus L. Var. scolymus L. (Fiori)] cultivars: studies and technological application on minimally processed production.

    Science.gov (United States)

    Todaro, Aldo; Peluso, Orazio; Catalano, Anna Eghle; Mauromicale, Giovanni; Spagna, Giovanni

    2010-02-10

    Several papers helped with the development of more methods to control browning, or study thermal polyphenol oxidase (PPO) inactivation, but did not provide any solutions to technological process problems and food process improvement. Artichokes [ Cynara cardunculus L. var. scolymus L. (Fiori)] are susceptible to browning; this alteration could affect and reduce the suitability for its use, fresh or processed. Within this study, the catecholase and cresolase activities of PPO from three different Sicilian artichokes cultivar were characterized with regard to substrate specificity and enzyme kinetics, optimum pH and temperature, temperature and pH stability, and inhibitor test; all of the results were used for technological purposes, particularly to optimize minimally processed productions (ready-to-eat and cook-chilled artichokes).

  4. Egg white hybrid nanoflower (EW-hNF) with biomimetic polyphenol oxidase reactivity: Synthesis, characterization and potential use in decolorization of synthetic dyes.

    Science.gov (United States)

    Altinkaynak, Cevahir; Kocazorbaz, Ebru; Özdemir, Nalan; Zihnioglu, Figen

    2018-04-01

    In this study, for the first time, we described organic-inorganic hybrid nanoflowers using crude egg white as the organic component and copper (II) ions as the inorganic component under the mild conditions. The synthesized egg white-inorganic hybrid nanoflowers (EW-hNFs) were characterized using SEM, EDX, XRD and FTIR analysis. The biomimetic Polyphenol/Peroxidase like activities of synthesized egg white-inorganic hybrid nanoflowers (EW-hNFs) were determined by using various phenolics with or without H 2 O 2 . Optimum pH and temperature, kinetic parameters, reusability, pH and thermal stability of EW-hNFs were also studied. The most noteworthy aspect of our study is that synthesized EW-hNFs which consist of only egg white proteins, showed polyphenol oxidase activity. Furthermore, potential use of the EW-hNFs in the discoloration of the some synthetic dyes was also evaluated. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Sensitive and Selective Ratiometric Fluorescence Probes for Detection of Intracellular Endogenous Monoamine Oxidase A.

    Science.gov (United States)

    Wu, Xiaofeng; Li, Lihong; Shi, Wen; Gong, Qiuyu; Li, Xiaohua; Ma, Huimin

    2016-01-19

    Monoamine oxidase A (MAO-A) is known to widely exist in most cell lines in the body, and its dysfunction (unusually high or low levels of MAO-A) is thought to be responsible for several psychiatric and neurological disorders. Thus, a sensitive and selective method for evaluating the relative MAO-A levels in different live cells is urgently needed to better understand the function of MAO-A, but to our knowledge such a method is still lacking. Herein, we rationally design two new ratiometric fluorescence probes (1 and 2) that can sensitively and selectively detect MAO-A. The probes are constructed by incorporating a recognition group of propylamine into the fluorescent skeleton of 1,8-naphthalimide, and the detection mechanism is based on amine oxidation and β-elimination to release the fluorophore (4-hydroxy-N-butyl-1,8-naphthalimide), which is verified by HPLC analysis. Reaction of the probes with MAO-A produces a remarkable fluorescence change from blue to green, and the ratio of fluorescence intensity at 550 and 454 nm is directly proportional to the concentration of MAO-A in the ranges of 0.5-1.5 and 0.5-2.5 μg/mL with detection limits of 1.1 and 10 ng/mL (k = 3) for probes 1 and 2, respectively. Surprisingly, these probes show strong fluorescence responses to MAO-A but almost none to MAO-B (one of two isoforms of MAO), indicating superior ability to distinguish MAO-A from MAO-B. The high specificity of the probes for MAO-A over MAO-B is further supported by different inhibitor experiments. Moreover, probe 1 displays higher sensitivity than probe 2 and is thus investigated to image the relative MAO-A levels in different live cells, such as HeLa and NIH-3T3 cells. It is found that the concentration of endogenous MAO-A in HeLa cells is approximately 1.8 times higher than that in NIH-3T3 cells, which is validated by the result from an ELISA kit. Additionally, the proposed probes may find more uses in the specific detection of MAO-A between the two isoforms of MAO

  6. Characterization of a Highly Thermostable and Organic Solvent-Tolerant Copper-Containing Polyphenol Oxidase with Dye-Decolorizing Ability from Kurthia huakuii LAM0618T.

    Directory of Open Access Journals (Sweden)

    Xiang Guo

    Full Text Available Laccases are green biocatalysts that possess attractive advantages for the treatment of resistant environmental pollutants and dye effluents. A putative laccase-like gene, laclK, encoding a protein of 29.3 kDa and belonging to the Cu-oxidase_4 superfamily, was cloned and overexpressed in Escherichia coli. The purified recombinant protein LaclK (LaclK was able to oxidize typical laccase substrates such as 2,6-dimethoxyphenol and l-dopamine. The characteristic adsorption maximums of typical laccases at 330 nm and 610 nm were not detected for LaclK. Cu2+ was essential for substrate oxidation, but the ratio of copper atoms/molecule of LaclK was determined to only be 1:1. Notably, the optimal temperature of LaclK was 85°C with 2,6-dimethoxyphenol as substrates, and the half-life approximately 3 days at 80°C. Furthermore, 10% (v/v organic solvents (methanol, ethanol, isopropyl alcohol, butyl alcohol, Triton x-100 or dimethyl sulfoxide could promote enzymatic activity. LaclK exhibited wide-spectrum decolorization ability towards triphenylmethane dyes, azo dyes and aromatic dyes, decolorizing 92% and 94% of Victoria Blue B (25 μM and Ethyl Violet (25 μM, respectively, at a concentration of 60 U/L after 1 h of incubation at 60°C. Overall, we characterized a novel thermostable and organic solvent-tolerant copper-containing polyphenol oxidase possessing dye-decolorizing ability. These unusual properties make LaclK an alternative for industrial applications, particularly processes that require high-temperature conditions.

  7. Enzyme characterisation, isolation and cDNA cloning of polyphenol oxidase in the hearts of palm of three commercially important species.

    Science.gov (United States)

    Shimizu, Milton Massao; Melo, Geraldo Aclécio; Brombini Dos Santos, Adriana; Bottcher, Alexandra; Cesarino, Igor; Araújo, Pedro; Magalhães Silva Moura, Jullyana Cristina; Mazzafera, Paulo

    2011-09-01

    Heart of palm (palmito) is the edible part of the apical meristem of palms and is considered a gourmet vegetable. Palmitos from the palms Euterpe edulis (Juçara) and Euterpe oleracea (Açaí) oxidise after harvesting, whereas almost no oxidation is observed in palmitos from Bactris gasipaes (Pupunha). Previous investigations showed that oxidation in Juçara and Açaí was mainly attributable to polyphenol oxidase (PPO; EC 1.14.18.1) activity. In this study, we partially purified PPOs from these three palmitos and analysed them for SDS activation, substrate specificity, inhibition by specific inhibitors, thermal stability, optimum pH and temperature conditions, Km and Ki. In addition, the total phenolic content and chlorogenic acid content were determined. Two partial cDNA sequences were isolated and sequenced from Açaí (EoPPO1) and Juçara (EePPO1). Semi-quantitative RT-PCR expression assays showed that Açaí and Juçara PPOs were strongly expressed in palmitos and weakly expressed in leaves. No amplification was observed for Pupunha samples. The lack of oxidation in the palmito Pupunha might be explained by the low PPO expression, low enzyme activity or the phenolic profile, particularly the low content of chlorogenic acid. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  8. Impact of high pressure processing on color, bioactive compounds, polyphenol oxidase activity, and microbiological attributes of pumpkin purée.

    Science.gov (United States)

    González-Cebrino, Francisco; Durán, Rocío; Delgado-Adámez, Jonathan; Contador, Rebeca; Bernabé, Rosario Ramírez

    2016-04-01

    Physicochemical parameters, bioactive compounds' content (carotenoids and total phenols), total antioxidant activity, and enzymatic activity of polyphenol oxidase (PPO) were evaluated after high pressure processing (HPP) on a pumpkin purée (cv. 'Butternut'). Three pressure levels (400, 500, and 600 MPa) were combined with three holding times (200, 400, and 600 s). The applied treatments reduced the levels of total aerobic mesophilic (TAM), total psychrophilic and psychrotrophic bacteria (TPP), and molds and yeasts (M&Y). All applied treatments did not affect enzymatic activity of PPO. Pressure level increased CIE L* values, which could enhance the lightness perception of high pressure (HP)-treated purées. No differences were found between the untreated and HP-treated purées regarding total phenols and carotenoids content (lutein, α-carotene, and β-carotene) and total antioxidant activity. HPP did not affect most quality parameters and maintained the levels of bioactive compounds. However, it did not achieve the complete inhibition of PPO, which could reduce the shelf-life of the pumpkin purée. © The Author(s) 2015.

  9. In silico analysis, mapping of regulatory elements and corresponding dna-protein interaction in polyphenol oxidase gene promoter from different rice varieties

    International Nuclear Information System (INIS)

    Mahmood, T.; Rehman, M.; Aziz, E.

    2015-01-01

    Polyphenol oxidase (PPO) is an important enzyme that has positive impact regarding plant resistance against different biotic and abiotic stresses. In the present study PPO promoter from six different rice varieties was amplified and then analyzed for cis- and trans-acting elements. The study revealed a total of 79 different cis-acting regulatory elements including 11 elements restricted to only one or other variety. Among six varieties Pakhal-Basmati had highest number (5) of these elements, whereas C-622 and Rachna-Basmati have no such sequences. Rachna-Basmati, IR-36-Basmati and Kashmir- Basmati had 1, 2 and 3 unique elements, respectively. Different elementsrelated to pathogen, salt and water stresses were found, which may be helpful in controlling PPO activity according to changing environment. Moreover, HADDOCK was used to understand molecular mechanism of PPO regulation and it was found that DNA-protein interactions are stabilized by many potential hydrogen bonds. Adenine and arginine were the most reactive residues in DNA and proteins respectively.Structural comparison of different protein-DNA complexes show that even a highly conserved transcriptional factor can adopt different conformations when they contact a different DNA binding sequence, however their stable interactions depend on the number of hydrogen bonds formed and distance. (author)

  10. Characterization of the polyphenol oxidase gene family reveals a novel microRNA involved in posttranscriptional regulation of PPOs in Salvia miltiorrhiza.

    Science.gov (United States)

    Li, Caili; Li, Dongqiao; Li, Jiang; Shao, Fenjuan; Lu, Shanfa

    2017-03-17

    Salvia miltiorrhiza is a well-known material of traditional Chinese medicine. Understanding the regulatory mechanisms of phenolic acid biosynthesis and metabolism are important for S. miltiorrhiza quality improvement. We report here that S. miltiorrhiza contains 19 polyphenol oxidases (PPOs), forming the largest PPO gene family in plant species to our knowledge. Analysis of gene structures and sequence features revealed the conservation and divergence of SmPPOs. SmPPOs were differentially expressed in plant tissues and eight of them were predominantly expressed in phloem and xylem, indicating that some SmPPOs are functionally redundant, whereas the others are associated with different physiological processes. Expression patterns of eighteen SmPPOs were significantly altered under MeJA treatment, and twelve were yeast extract and Ag + -responsive, suggesting the majority of SmPPOs are stress-responsive. Analysis of high-throughput small RNA sequences and degradome data showed that miR1444-mediated regulation of PPOs existing in P. trichocarpa is absent from S. miltiorrhiza. Instead, a subset of SmPPOs was posttranscriptionally regulated by a novel miRNA, termed Smi-miR12112. It indicates the specificity and significance of miRNA-mediated regulation of PPOs. The results shed light on the regulation of SmPPO expression and suggest the complexity of SmPPO-associated phenolic acid biosynthesis and metabolism.

  11. Composition, physicochemical properties and thermal inactivation kinetics of polyphenol oxidase and peroxidase from coconut (Cocos nucifera) water obtained from immature, mature and overly-mature coconut.

    Science.gov (United States)

    Tan, Thuan-Chew; Cheng, Lai-Hoong; Bhat, Rajeev; Rusul, Gulam; Easa, Azhar Mat

    2014-01-01

    Composition, physicochemical properties and enzyme inactivation kinetics of coconut water were compared between immature (IMC), mature (MC) and overly-mature coconuts (OMC). Among the samples studied, pH, turbidity and mineral contents for OMC water was the highest, whereas water volume, titratable acidity, total soluble solids and total phenolics content for OMC water were the lowest. Maturity was found to affect sugar contents. Sucrose content was found to increase with maturity, and the reverse trend was observed for fructose and glucose. Enzyme activity assessment showed that polyphenol oxidase (PPO) in all samples was more heat resistant than peroxidase (POD). Compared to IMC and MC, PPO and POD from OMC water showed the lowest thermal resistance, with D83.3°C=243.9s (z=27.9°C), and D83.3°C=129.9s (z=19.5°C), respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Development of a Polyphenol Oxidase Biosensor from Jenipapo Fruit Extract (Genipa americana L. and Determination of Phenolic Compounds in Textile Industrial Effluents

    Directory of Open Access Journals (Sweden)

    Rafael Souza Antunes

    2018-05-01

    Full Text Available In this work, an innovative polyphenol oxidase biosensor was developed from Jenipapo (Genipa americana L. fruit and used to assess phenolic compounds in industrial effluent samples obtained from a textile industry located in Jaraguá-GO, Brasil. The biosensor was prepared and optimized according to: the proportion of crude vegetal extract, pH and overall voltammetric parameters for differential pulse voltammetry. The calibration curve presented a linear interval from 10 to 310 µM (r2 = 0.9982 and a limit of detection of 7 µM. Biosensor stability was evaluated throughout 15 days, and it exhibited 88.22% of the initial response. The amount of catechol standard recovered post analysis varied between 87.50% and 96.00%. Moreover, the biosensor was able to detect phenolic compounds in a real sample, and the results were in accordance with standard spectrophotometric assays. Therefore, the innovatively-designed biosensor hereby proposed is a promising tool for phenolic compound detection and quantification when environmental contaminants are concerned.

  13. Variation of the Phytochemical Constituents and Antioxidant Activities of Zingiber officinale var. rubrum Theilade Associated with Different Drying Methods and Polyphenol Oxidase Activity.

    Science.gov (United States)

    Ghasemzadeh, Ali; Jaafar, Hawa Z E; Rahmat, Asmah

    2016-06-17

    The effects of different drying methods (freeze drying, vacuum oven drying, and shade drying) on the phytochemical constituents associated with the antioxidant activities of Z. officinale var. rubrum Theilade were evaluated to determine the optimal drying process for these rhizomes. Total flavonoid content (TFC), total phenolic content (TPC), and polyphenol oxidase (PPO) activity were measured using the spectrophotometric method. Individual phenolic acids and flavonoids, 6- and 8-gingerol and shogaol were identified by ultra-high performance liquid chromatography method. Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used for the evaluation of antioxidant activities. The highest reduction in moisture content was observed after freeze drying (82.97%), followed by vacuum oven drying (80.43%) and shade drying (72.65%). The highest TPC, TFC, and 6- and 8-shogaol contents were observed in samples dried by the vacuum oven drying method compared to other drying methods. The highest content of 6- and 8-gingerol was observed after freeze drying, followed by vacuum oven drying and shade drying methods. Fresh samples had the highest PPO activity and lowest content of flavonoid and phenolic acid compounds compared to dried samples. Rhizomes dried by the vacuum oven drying method represent the highest DPPH (52.9%) and FRAP activities (566.5 μM of Fe (II)/g DM), followed by freeze drying (48.3% and 527.1 μM of Fe (II)/g DM, respectively) and shade drying methods (37.64% and 471.8 μM of Fe (II)/g DM, respectively) with IC50 values of 27.2, 29.1, and 34.8 μg/mL, respectively. Negative and significant correlations were observed between PPO and antioxidant activity of rhizomes. Vacuum oven dried rhizomes can be utilized as an ingredient for the development of value-added food products as they contain high contents of phytochemicals with valuable antioxidant potential.

  14. Combined effect of ultrasound, heat, and pressure on Escherichia coli O157:H7, polyphenol oxidase activity, and anthocyanins in blueberry (Vaccinium corymbosum) juice.

    Science.gov (United States)

    Zhu, Jinyan; Wang, Yuehua; Li, Xinghe; Li, Bin; Liu, Suwen; Chang, Nan; Jie, Ding; Ning, Chong; Gao, Haiyan; Meng, Xianjun

    2017-07-01

    The objective of this study was to evaluate the effect of different treatments-heat treatment (HT), sonication (SC), thermosonication (TS), manosonication (MS), manothermal (MT), and manothermosonication (MTS) on Escherichia coli O157:H7, polyphenol oxidase (PPO), and anthocyanin content in blueberry juice. First, samples were treated at different temperatures (30, 40, 50, 60, 70, and 80°C) and power intensities (280, 420, 560, and 700W) for 10min. Subsequently, samples were treated using combinations of power intensity and mild temperature for 10min. For further study, samples were treated using HT (80°C), TS (40°C, 560W), MT (350MPa, 40°C), MS (560W, 5min/350MPa), or MTS (560W, 5min, 40°C/350MPa, 40°C) for 5, 10, 15, 20min for each treatment, and the results compared between treatments. HT significantly reduced PPO activation (2.05% residual activity after only 5min), and resulted in a 2.00-log reduction in E. coli O157:H7 and an 85.25% retention of anthocyanin. Escherichia coli O157:H7 was slightly inactivated by TS after 5min (0.17-log reduction), while residual PPO activity was 23.36% and anthocyanin retention was 98.48%. However, Escherichia coli O157:H7 was rapidly inactivated by MTS (5.85-log reduction) after 5min, while anthocyanin retention was 97.49% and residual PPO activity dropped to 10.91%. The destruction of E. coli cells as a result of these treatments were confirmed using SEM and TEM. Therefore, a combination of sonication, high pressure, and mild heat allows the safety of blueberry juice to be maintained without compromising the retention of desirable antioxidant compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. High isostatic pressure and thermal processing of açaí fruit (Euterpe oleracea Martius): Effect on pulp color and inactivation of peroxidase and polyphenol oxidase.

    Science.gov (United States)

    Jesus, Ana Laura Tibério de; Leite, Thiago Soares; Cristianini, Marcelo

    2018-03-01

    The present study evaluated the effect of high isostatic pressure (HIP) on the activity of peroxidase (POD) and polyphenol oxidase (PPO) from açaí. Açaí pulp was submitted to several combinations of pressure (400, 500, 600MPa), temperature (25 and 65°C) for 5 and 15min. The combined effect of HIP technology and high temperatures (690MPa by 2 and 5min at 80°C) was also investigated and compared to the conventional thermal treatment (85°C/1min). POD and PPO enzyme activity and instrumental color were examined after processing and after 24h of refrigerated storage. Results showed stability of POD for all pressures at 25°C, which proved to be heat-resistant and baro-resistant at 65°C. For PPO, the inactivation at 65°C was 71.7% for 600MPa after 15min. In general, the increase in temperature from 25°C to 65°C reduced the PPO relative activity with no changes in color. Although the thermal treatment and the HIP (690MPa) along with high temperature (80°C) reduced the PPO relative activity, and relevant darkening was observed in the processed samples. Thus, it can be concluded that POD is more baro-resistant than PPO in açaí pulp subjected to the same HIP processing conditions and processing at 600MPa/65°C for 5min may be an effective alternative for thermal pasteurization treatments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Intracellular expression of reactive oxygen species-generating NADPH oxidase NOX4 in normal and cancer thyroid tissues

    NARCIS (Netherlands)

    Weyemi, Urbain; Caillou, Bernard; Talbot, Monique; Ameziane-El-Hassani, Rabii; Lacroix, Ludovic; Lagent-Chevallier, Odile; Al Ghuzlan, Abir; Roos, Dirk; Bidart, Jean-Michel; Virion, Alain; Schlumberger, Martin; Dupuy, Corinne

    2010-01-01

    NADPH oxidase 4 (NOX4) belongs to the NOX family that generates reactive oxygen species (ROS). Function and tissue distribution of NOX4 have not yet been entirely clarified. To date, in the thyroid gland, only DUOX1/2 NOX systems have been described. NOX4 mRNA expression, as shown by real-time PCR,

  17. Roselle Polyphenols Exert Potent Negative Inotropic Effects via Modulation of Intracellular Calcium Regulatory Channels in Isolated Rat Heart.

    Science.gov (United States)

    Lim, Yi-Cheng; Budin, Siti Balkis; Othman, Faizah; Latip, Jalifah; Zainalabidin, Satirah

    2017-07-01

    Roselle (Hibiscus sabdariffa Linn.) calyces have demonstrated propitious cardioprotective effects in animal and clinical studies; however, little is known about its action on cardiac mechanical function. This study was undertaken to investigate direct action of roselle polyphenols (RP) on cardiac function in Langendorff-perfused rat hearts. We utilized RP extract which consists of 12 flavonoids and seven phenolic acids (as shown by HPLC profiling) and has a safe concentration range between 125 and 500 μg/ml in this study. Direct perfusion of RP in concentration-dependent manner lowered systolic function of the heart as shown by lowered LVDP and dP/dt max , suggesting a negative inotropic effect. RP also reduced heart rate (negative chronotropic action) while simultaneously increasing maximal velocity of relaxation (positive lusitropic action). Conversely, RP perfusion increased coronary pressure, an indicator for improvement in coronary blood flow. Inotropic responses elicited by pharmacological agonists for L-type Ca 2+ channel [(±)-Bay K 8644], ryanodine receptor (4-chloro-m-cresol), β-adrenergic receptor (isoproterenol) and SERCA blocker (thapsigargin) were all abolished by RP. In conclusion, RP elicits negative inotropic, negative chronotropic and positive lusitropic responses by possibly modulating calcium entry, release and reuptake in the heart. Our findings have shown the potential use of RP as a therapeutic agent to treat conditions like arrhythmia.

  18. Effect of different NADH oxidase levels on glucose metabolism by Lactococus lactis : kinetics of intracellular metabolite pools determined by in vivo nuclear magnetic resonance

    NARCIS (Netherlands)

    Neves, A.R.; Ramos, A.; Costa, H.; Swam, van I.I.; Hugenholtz, J.; Kleerebezem, M.; Vos, de W.M.; Santos, H.

    2002-01-01

    Three isogenic strains of Lactococcus lactis with different levels of H2O-forming NADH oxidase activity were used to study the effect of oxygen on glucose metabolism: the parent strain L. lactis MG1363, a NOX- strain harboring a deletion of the gene coding for H2O-forming NADH oxidase, and a NOX

  19. Comparative study of the banana pulp browning process of 'Giant Dwarf' and FHIA-23 during fruit ripening based on image analysis and the polyphenol oxidase and peroxidase biochemical properties.

    Science.gov (United States)

    Escalante-Minakata, Pilar; Ibarra-Junquera, Vrani; Ornelas-Paz, José de Jesús; García-Ibáñez, Victoria; Virgen-Ortíz, José J; González-Potes, Apolinar; Pérez-Martínez, Jaime D; Orozco-Santos, Mario

    2018-01-01

    This work presents a novel method to associate the polyphenol oxidase (PPO) and the peroxidase (POD) activities with the ripening-mediated color changes in banana peel and pulp by computational image analysis. The method was used to follow up the de-greening of peel and browning of homogenized pulp from 'Giant Dwarf' (GD: Musa AAA, subgroup Cavendish) and FHIA-23 (tetraploid hybrid, AAAA) banana cultivars. In both cultivars, the color changes of peel during the ripening process clearly showed four stages, which were used to group the fruit into ripening stages. The PPO and POD were extracted from pulp of fruit at these ripening stages, precipitated, and partially purified by gel filtration chromatography. Moreover, the pulp browning was digitally monitored after homogenization for a span time of up to 120 min. The browning level was higher for GD than FHIA-23 tissues. This fact correlated with an 11.7-fold higher PPO activity in the GD cultivar, as compared with that of FHIA-23. POD activity was 8.1 times higher for GD as compared that that of FHIA-23.

  20. Role of ascorbic acid in the inhibition of polyphenol oxidase and the prevention of browning in different browning-sensitive Lactuca sativa var. capitata (L.) and Eruca sativa (Mill.) stored as fresh-cut produce.

    Science.gov (United States)

    Landi, Marco; Degl'Innocenti, Elena; Guglielminetti, Lorenzo; Guidi, Lucia

    2013-06-01

    Polyphenol oxidase (PPO) and, to a minor extent, peroxidase (POD) represent the key enzymes involved in enzymatic browning, a negative process induced by cutting fresh-cut produce such as lettuce (Lactuca sativa) and rocket salad (Eruca sativa). Although ascorbic acid is frequently utilised as an anti-browning agent, its mechanism in the prevention of the browning phenomenon is not clearly understood. The activity of PPO and POD and their isoforms in lettuce (a high-browning and low-ascorbic acid species) and rocket salad (a low-browning and high-ascorbic species) was characterised. The kinetic parameters of PPO and in vitro ascorbic acid-PPO inhibition were also investigated. In rocket salad, PPO activity was much lower than that in lettuce and cutting induced an increase in PPO activity only in lettuce. Exogenous ascorbic acid (5 mmol L(-1)) reduced PPO activity by about 90% in lettuce. POD did not appear to be closely related to browning in lettuce. PPO is the main enzyme involved in the browning phenomenon; POD appears to play a minor role. The concentration of endogenous ascorbic acid in rocket salad was related to its low-browning sensitivity after cutting. In lettuce, the addition of ascorbic acid directly inhibited PPO activity. The results suggest that the high ascorbic acid content found in rocket salad plays an effective role in reducing PPO activity. © 2012 Society of Chemical Industry.

  1. Multiple origins of the phenol reaction negative phenotype in foxtail millet, Setaria italica (L.) P. Beauv., were caused by independent loss-of-function mutations of the polyphenol oxidase (Si7PPO) gene during domestication.

    Science.gov (United States)

    Inoue, Takahiko; Yuo, Takahisa; Ohta, Takeshi; Hitomi, Eriko; Ichitani, Katsuyuki; Kawase, Makoto; Taketa, Shin; Fukunaga, Kenji

    2015-08-01

    Foxtail millet shows variation in positive phenol color reaction (Phr) and negative Phr in grains, but predominant accessions of this crop are negative reaction type, and the molecular genetic basis of the Phr reaction remains unresolved. In this article, we isolated polyphenol oxidase (PPO) gene responsible for Phr using genome sequence information and investigated molecular genetic basis of negative Phr and crop evolution of foxtail millet. First of all, we searched for PPO gene homologs in a foxtail millet genome database using a rice PPO gene as a query and successfully found three copies of the PPO gene. One of the PPO gene homologs on chromosome 7 showed the highest similarity with PPO genes expressed in hulls (grains) of other cereal species including rice, wheat, and barley and was designated as Si7PPO. Phr phenotypes and Si7PPO genotypes completely co-segregated in a segregating population. We also analyzed the genetic variation conferring negative Phr reaction. Of 480 accessions of the landraces investigated, 87 (18.1 %) showed positive Phr and 393 (81.9 %) showed negative Phr. In the 393 Phr negative accessions, three types of loss-of-function Si7PPO gene were predominant and independently found in various locations. One of them has an SNP in exon 1 resulting in a premature stop codon and was designated as stop codon type, another has an insertion of a transposon (Si7PPO-TE1) in intron 2 and was designated as TE1-insertion type, and the other has a 6-bp duplication in exon 3 resulting in the duplication of 2 amino acids and was designated as 6-bp duplication type. As a rare variant of the stop codon type, one accession additionally has an insertion of a transposon, Si7PPO-TE2, in intron 2 and was designated as "stop codon +TE2 insertion type". The geographical distribution of accessions with positive Phr and those with three major types of negative Phr was also investigated. Accessions with positive Phr were found in subtropical and tropical regions at

  2. Polyphenols in preventing endothelial dysfunction

    Directory of Open Access Journals (Sweden)

    Sylwia Biegańska-Hensoldt

    2017-03-01

    Full Text Available One of the main causes of mortality in developed countries is atherosclerosis. The pathogenesis of atherosclerosis is associated with endothelial dysfunction. Consumption of food rich in natural antioxidants including polyphenols significantly improves endothelial cells functions.Polyphenols have a beneficial effect on the human body and play an important part in protecting the cardiovascular system. Polyphenols present in food have antioxidant, anti-inflammatory, antihypertensive, antithrombotic and antiproliferative properties. Catechins cause an increase in the activity of endothelial nitric oxide synthase (eNOS and increased production of nitric oxide (NO and decrease in blood pressure. Catechins also reduce platelet adhesion, lower the concentration of C-reactive protein and tumor necrosis factor alpha and interleukin-6. Resveratrol inhibits NADPH oxidase expression, increases the expression of eNOS and NO production as well as decreases the expression of proinflammatory cytokines, and also lowers the concentration of the soluble forms of adhesion molecules – sICAM-1 and sVCAM-1 in blood. Quercetin reduces the blood level of low density lipoprotein cholesterol, lowers blood pressure, reduces the concentration of C-reactive protein and F2-isoprostane level. Curcumin has antagonistic activity to homocysteine. Curcumin increases the expression of eNOS and reduces oxidative DNA damage in rat cardiomyocytes. Numerous attempts are taken for improving the bioavailability of polyphenols in order to increase their use in the body.

  3. A New Laccase Biosensor For Polyphenols Determination

    Directory of Open Access Journals (Sweden)

    M. J.F. Rebelo

    2003-06-01

    Full Text Available The relevance of polyphenols in human health is a well known fact. Prompted by that, a very intensive research has been directed to get a method to detect them, wich will improve the current ones. Laccase (p-diphenol:dioxygen oxidoreductase EC 1.10.3.2 is a multi-copper oxidase, wich couples catalytic oxidation of phenolic substrates with four electron reduction of dioxygen to water [1]. A maximum catalytic response in oxigenated electrolyte was observed between 4.5 and 5.5 [2], while for pH > 6.9 the laccase was found to be inactive [3]. We prepared a biosensor with laccase immobilised on a polyether sulphone membrane, at pH 4.5, wich was applied at Universal Sensors base electrode. Reduction of the product of oxidation of several polyphenols, catalysed by laccase, was done at a potential for wich the polyphenol of interest was found to respond. Reduction of catechol was found to occur at a potential of -200mV, wich is often referred to in the literature for polyphenolic biosensors. However other polyphenols did not respond at that potential. It was observed that (+- catechin produced a very large cathodic current when +100mV were applied to the laccase biosensor, both in aqueous acetate and 12% ethanol acetate buffer, whereas caffeic acid responded at -50mV. Other polyphenols tested were gallic acid, malvidin, quercetin, rutin, trans-resveratrol

  4. Khz-cp (crude polysaccharide extract obtained from the fusion of Ganoderma lucidum and Polyporus umbellatus mycelia) induces apoptosis by increasing intracellular calcium levels and activating P38 and NADPH oxidase-dependent generation of reactive oxygen species in SNU-1 cells.

    Science.gov (United States)

    Kim, Tae Hwan; Kim, Ju Sung; Kim, Zoo Haye; Huang, Ren Bin; Chae, Young Lye; Wang, Ren Sheng

    2014-07-10

    Khz-cp is a crude polysaccharide extract that is obtained after nuclear fusion in Ganoderma lucidum and Polyporus umbellatus mycelia (Khz). It inhibits the growth of cancer cells. Khz-cp was extracted by solvent extraction. The anti-proliferative activity of Khz-cp was confirmed by using Annexin-V/PI-flow cytometry analysis. Intracellular calcium increase and measurement of intracellular reactive oxygen species (ROS) were performed by using flow cytometry and inverted microscope. SNU-1 cells were treated with p38, Bcl-2 and Nox family siRNA. siRNA transfected cells was employed to investigate the expression of apoptotic, growth and survival genes in SNU-1 cells. Western blot analysis was performed to confirm the expression of the genes. In the present study, Khz-cp induced apoptosis preferentially in transformed cells and had only minimal effects on non-transformed cells. Furthermore, Khz-cp was found to induce apoptosis by increasing the intracellular Ca2+ concentration ([Ca2+]i) and activating P38 to generate reactive oxygen species (ROS) via NADPH oxidase and the mitochondria. Khz-cp-induced apoptosis was caspase dependent and occurred via a mitochondrial pathway. ROS generation by NADPH oxidase was critical for Khz-cp-induced apoptosis, and although mitochondrial ROS production was also required, it appeared to occur secondary to ROS generation by NADPH oxidase. Activation of NADPH oxidase was shown by the translocation of the regulatory subunits p47phox and p67phox to the cell membrane and was necessary for ROS generation by Khz-cp. Khz-cp triggered a rapid and sustained increase in [Ca2+]i that activated P38. P38 was considered to play a key role in the activation of NADPH oxidase because inhibition of its expression or activity abrogated membrane translocation of the p47phox and p67phox subunits and ROS generation. In summary, these data indicate that Khz-cp preferentially induces apoptosis in cancer cells and that the signaling mechanisms involve an

  5. Impact of Dietary Polyphenols on Carbohydrate Metabolism

    Directory of Open Access Journals (Sweden)

    Kati Hanhineva

    2010-03-01

    Full Text Available Polyphenols, including flavonoids, phenolic acids, proanthocyanidins and resveratrol, are a large and heterogeneous group of phytochemicals in plant-based foods, such as tea, coffee, wine, cocoa, cereal grains, soy, fruits and berries. Growing evidence indicates that various dietary polyphenols may influence carbohydrate metabolism at many levels. In animal models and a limited number of human studies carried out so far, polyphenols and foods or beverages rich in polyphenols have attenuated postprandial glycemic responses and fasting hyperglycemia, and improved acute insulin secretion and insulin sensitivity. The possible mechanisms include inhibition of carbohydrate digestion and glucose absorption in the intestine, stimulation of insulin secretion from the pancreatic b-cells, modulation of glucose release from the liver, activation of insulin receptors and glucose uptake in the insulin-sensitive tissues, and modulation of intracellular signalling pathways and gene expression. The positive effects of polyphenols on glucose homeostasis observed in a large number of in vitro and animal models are supported by epidemiological evidence on polyphenol-rich diets. To confirm the implications of polyphenol consumption for prevention of insulin resistance, metabolic syndrome and eventually type 2 diabetes, human trials with well-defined diets, controlled study designs and clinically relevant end-points together with holistic approaches e.g., systems biology profiling technologies are needed.

  6. Polyphenols and Sunburn

    Directory of Open Access Journals (Sweden)

    Suzana Saric

    2016-09-01

    Full Text Available Polyphenols are antioxidant molecules found in many foods such as green tea, chocolate, grape seeds, and wine. Polyphenols have antioxidant, anti-inflammatory, and antineoplastic properties. Growing evidence suggests that polyphenols may be used for the prevention of sunburns as polyphenols decrease the damaging effects of ultraviolet A (UVA and ultraviolet B (UVB radiation on the skin. This review was conducted to examine the evidence for use of topically and orally ingested polyphenols in prevention of sunburns. The PubMed database was searched for studies that examined polyphenols and its effects on sunburns. Of the 27 studies found, 15 met the inclusion criteria. Seven studies were conducted on human subjects and eight on animals (mice and rats. Eleven studies evaluated the effects of topical polyphenols, two studies examined ingested polyphenols, and two studies examined both topical and ingested polyphenols. Polyphenol sources included the following plant origins: green tea, white tea, cocoa, Romanian propolis (RP, Calluna vulgaris (Cv, grape seeds, honeybush, and Lepidium meyenii (maca. Eight studies examined green tea. Overall, based on the studies, there is evidence that polyphenols in both oral and topical form may provide protection from UV damage and sunburn, and thus are beneficial to skin health. However, current studies are limited and further research is necessary to evaluate the efficacy, mechanism of action, and potential side effects of various forms and concentrations of polyphenols.

  7. Polyphenols and Sunburn.

    Science.gov (United States)

    Saric, Suzana; Sivamani, Raja K

    2016-09-09

    Polyphenols are antioxidant molecules found in many foods such as green tea, chocolate, grape seeds, and wine. Polyphenols have antioxidant, anti-inflammatory, and antineoplastic properties. Growing evidence suggests that polyphenols may be used for the prevention of sunburns as polyphenols decrease the damaging effects of ultraviolet A (UVA) and ultraviolet B (UVB) radiation on the skin. This review was conducted to examine the evidence for use of topically and orally ingested polyphenols in prevention of sunburns. The PubMed database was searched for studies that examined polyphenols and its effects on sunburns. Of the 27 studies found, 15 met the inclusion criteria. Seven studies were conducted on human subjects and eight on animals (mice and rats). Eleven studies evaluated the effects of topical polyphenols, two studies examined ingested polyphenols, and two studies examined both topical and ingested polyphenols. Polyphenol sources included the following plant origins: green tea, white tea, cocoa, Romanian propolis (RP), Calluna vulgaris (Cv), grape seeds, honeybush, and Lepidium meyenii (maca). Eight studies examined green tea. Overall, based on the studies, there is evidence that polyphenols in both oral and topical form may provide protection from UV damage and sunburn, and thus are beneficial to skin health. However, current studies are limited and further research is necessary to evaluate the efficacy, mechanism of action, and potential side effects of various forms and concentrations of polyphenols.

  8. Effects of water blanching on polyphenol reaction kinetics and quality of cocoa beans

    Science.gov (United States)

    Menon, A. S.; Hii, C. L.; Law, C. L.; Suzannah, S.; Djaeni, M.

    2015-12-01

    Several studies have been reported on the potential health benefits of cocoa polyphenols. However, drying has an inhibitory effect on the substantial recovery of cocoa polyphenols. This is majorly because of the high degradation of polyphenol compounds as well as the enhanced activity of polyphenol oxidases; a pre-cursor for browning of polyphenols during drying. Pre-treatment technique such as water blanching (80° and 90°C for 5 min, 10 min and 15 min exposure times respectively) can inactivate the polyphenol oxidases enzyme and promote high percent of the polyphenol recovery in dried cocoa bean. The degradation kinetics of cocoa polyphenols during hot water blanching are analyzed; The rate constant for the polyphenol degradation after blanching was found to be ranging from 0.0208 to 0.0340 /min. The results for dried fresh cocoa beans showed an optimal level of polyphenol recovery (118 mg GAE/g) when blanched at 90°C for 5 minutes duration. The antioxidant activity is also analyzed using DPPH scavenging assay.

  9. Biodegradation of phenolic compounds with oxidases from sorghum and non-defined mixed bacterium media

    International Nuclear Information System (INIS)

    Obame, C. E. L.; Savadogo, P. W.; Mamoudou, D. H.; Dembele, R. H.; Traore, A. S.

    2009-01-01

    The biodegradation of the phenolic compounds is performed using oxidative enzymes, e. g. polyphenol oxidases (PPOs) and peroxidases (POXs). These oxidases displaying a wide spectrum for the oxidation of phenolic compounds were isolated either from sorghum or mixed bacteria. Spectrophotometric methods were used to assess the monophenolase and diphenolase activities of PPOs as well as the hydrogen-dependant oxidation of POXs. (Author)

  10. Biodegradation of phenolic compounds with oxidases from sorghum and non-defined mixed bacterium media

    Energy Technology Data Exchange (ETDEWEB)

    Obame, C. E. L.; Savadogo, P. W.; Mamoudou, D. H.; Dembele, R. H.; Traore, A. S.

    2009-07-01

    The biodegradation of the phenolic compounds is performed using oxidative enzymes, e. g. polyphenol oxidases (PPOs) and peroxidases (POXs). These oxidases displaying a wide spectrum for the oxidation of phenolic compounds were isolated either from sorghum or mixed bacteria. Spectrophotometric methods were used to assess the monophenolase and diphenolase activities of PPOs as well as the hydrogen-dependant oxidation of POXs. (Author)

  11. Polyphenols and Glycemic Control

    Directory of Open Access Journals (Sweden)

    Yoona Kim

    2016-01-01

    Full Text Available Growing evidence from animal studies supports the anti-diabetic properties of some dietary polyphenols, suggesting that dietary polyphenols could be one dietary therapy for the prevention and management of Type 2 diabetes. This review aims to address the potential mechanisms of action of dietary polyphenols in the regulation of glucose homeostasis and insulin sensitivity based on in vitro and in vivo studies, and to provide a comprehensive overview of the anti-diabetic effects of commonly consumed dietary polyphenols including polyphenol-rich mixed diets, tea and coffee, chocolate and cocoa, cinnamon, grape, pomegranate, red wine, berries and olive oil, with a focus on human clinical trials. Dietary polyphenols may inhibit α-amylase and α-glucosidase, inhibit glucose absorption in the intestine by sodium-dependent glucose transporter 1 (SGLT1, stimulate insulin secretion and reduce hepatic glucose output. Polyphenols may also enhance insulin-dependent glucose uptake, activate 5′ adenosine monophosphate-activated protein kinase (AMPK, modify the microbiome and have anti-inflammatory effects. However, human epidemiological and intervention studies have shown inconsistent results. Further intervention studies are essential to clarify the conflicting findings and confirm or refute the anti-diabetic effects of dietary polyphenols.

  12. Antioxidative and apoptotic properties of polyphenolic extracts from edible part of artichoke (Cynara scolymus L.) on cultured rat hepatocytes and on human hepatoma cells.

    Science.gov (United States)

    Miccadei, Stefania; Di Venere, Donato; Cardinali, Angela; Romano, Ferdinando; Durazzo, Alessandra; Foddai, Maria Stella; Fraioli, Rocco; Mobarhan, Sohrab; Maiani, Giuseppe

    2008-01-01

    Cultured rat hepatocytes and human hepatoma HepG2 cells were used to evaluate the hepatoprotective properties of polyphenolic extracts from the edible part of artichoke (AE). The hepatocytes were exposed to H2O2generated in situ by glucose oxidase and were treated with either AE, or pure chlorogenic acid (ChA) or with the well known antioxidant, N, N'-diphenyl-p-phenilenediamine (DPPD). Addition of glucose oxidase to the culture medium caused depletion of intracellular glutathione (GSH) content, accumulation of malondialdehyde (MDA) in the cultures, as a lipid peroxidation indicator, and cell death. These results demonstrated that AE protected cells from the oxidative stress caused by glucose oxidase, comparable to DPPD. Furthermore, AE, as well as ChA, prevented the loss of total GSH and the accumulation of MDA. Treatment of HepG2 cells for 24 h with AE reduced cell viability in a dose-dependent manner, however, ChA had no prominent effects on the cell death rate. Similarly, AE rather than ChA induced apoptosis, measured by flow cytometric analysis of annexin and by activation of caspase-3, in HepG2 cells. Our findings indicate that AE had a marked antioxidative potential that protects hepatocytes from an oxidative stress. Furthermore, AE reduced cell viability and had an apoptotic activity on a human liver cancer cell line.

  13. Managing hypertension by polyphenols.

    Science.gov (United States)

    Fernández-Arroyo, Salvador; Camps, Jordi; Menendez, Javier A; Joven, Jorge

    2015-06-01

    Some polyphenols, obtained from plants of broad use, induce a favorable endothelial response in hypertension and beneficial effects in the management of other metabolic cardiovascular risks. Previous studies in our laboratories using the calyces of Hibiscus sabdariffa as a source of polyphenols show that significant effects on hypertension are noticeable in humans only when provided in high amounts. Available data are suggestive in animal models and ex vivo experiments, but data in humans are difficult to acquire. Additionally, and despite the low bioavailability of polyphenols, intervention studies provide evidence for the protective effects of secondary plant metabolites. Assumptions on public health benefits are limited by the lack of scientific knowledge, robust data derived from large randomized clinical trials, and an accurate assessment of the bioactive components provided by common foodstuff. Because it is likely that clinical effects are the result of multiple interactions among different polyphenols rather than the isolated action of unique compounds, to provide polyphenol-rich botanical extracts as dietary supplements is a suggestive option. Unfortunately, the lack of patent perspectives for the pharmaceutical industries and the high cost of production and release for alimentary industries will hamper the performance of the necessary clinical trials. Here we briefly discuss whether and how such limitations may complicate the extensive use of plant-derived products in the management of hypertension and which steps are the necessary to deal with the predictable complexity in a possible clinical practice. Georg Thieme Verlag KG Stuttgart · New York.

  14. Polyphenol oxidase-based luminescent enzyme hydrogel: an ...

    Indian Academy of Sciences (India)

    2018-02-02

    Feb 2, 2018 ... ranging from educational domain to industrial research. [3–8]. ... All chemicals and related consumables were purchased from Sigma-Aldrich and used as ... The non-toxic nature of the supramolecular hydrogel [9] is an added ...

  15. Allelic variations of functional markers for polyphenol oxidase (PPO)

    Indian Academy of Sciences (India)

    genes in Indian bread wheat (Triticum aestivum L.) cultivars. Rajender Singh, Umesh Goutam, R. K. Gupta, G. C. Pandey, Jag Shoran and Ratan Tiwari. J. Genet. 88, 325–329. Figure 1. Phenol colour reaction of kernels. Kernels without treatment by phenol solution are shown as controls. Phenol colour reaction of kernels; ...

  16. Effect of heat treatment on polyphenol oxidase and peroxidase ...

    African Journals Online (AJOL)

    GREGO

    2006-12-18

    Dec 18, 2006 ... enzymes in plant and its resistance to heat has been reported by a ... sintered glass funnel and washed with cold acetone under low vacuum ... Peroxidase activity was determined by measuring the colour deve- lopment at ...

  17. Polyphenol Compound as a Transcription Factor Inhibitor

    Directory of Open Access Journals (Sweden)

    Seyeon Park

    2015-10-01

    Full Text Available A target-based approach has been used to develop novel drugs in many therapeutic fields. In the final stage of intracellular signaling, transcription factor–DNA interactions are central to most biological processes and therefore represent a large and important class of targets for human therapeutics. Thus, we focused on the idea that the disruption of protein dimers and cognate DNA complexes could impair the transcriptional activation and cell transformation regulated by these proteins. Historically, natural products have been regarded as providing the primary leading compounds capable of modulating protein–protein or protein-DNA interactions. Although their mechanism of action is not fully defined, polyphenols including flavonoids were found to act mostly as site-directed small molecule inhibitors on signaling. There are many reports in the literature of screening initiatives suggesting improved drugs that can modulate the transcription factor interactions responsible for disease. In this review, we focus on polyphenol compound inhibitors against dimeric forms of transcription factor components of intracellular signaling pathways (for instance, c-jun/c-fos (Activator Protein-1; AP-1, c-myc/max, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB and β-catenin/T cell factor (Tcf.

  18. Polyphenol Compound as a Transcription Factor Inhibitor.

    Science.gov (United States)

    Park, Seyeon

    2015-10-30

    A target-based approach has been used to develop novel drugs in many therapeutic fields. In the final stage of intracellular signaling, transcription factor-DNA interactions are central to most biological processes and therefore represent a large and important class of targets for human therapeutics. Thus, we focused on the idea that the disruption of protein dimers and cognate DNA complexes could impair the transcriptional activation and cell transformation regulated by these proteins. Historically, natural products have been regarded as providing the primary leading compounds capable of modulating protein-protein or protein-DNA interactions. Although their mechanism of action is not fully defined, polyphenols including flavonoids were found to act mostly as site-directed small molecule inhibitors on signaling. There are many reports in the literature of screening initiatives suggesting improved drugs that can modulate the transcription factor interactions responsible for disease. In this review, we focus on polyphenol compound inhibitors against dimeric forms of transcription factor components of intracellular signaling pathways (for instance, c-jun/c-fos (Activator Protein-1; AP-1), c-myc/max, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and β-catenin/T cell factor (Tcf)).

  19. Polyphenol-rich apple (Malus domestica L.) peel extract attenuates arsenic trioxide induced cardiotoxicity in H9c2 cells via its antioxidant activity.

    Science.gov (United States)

    Vineetha, Vadavanath Prabhakaran; Girija, Seetharaman; Soumya, Rema Sreenivasan; Raghu, Kozhiparambil Gopalan

    2014-03-01

    Evidences suggest that apple peel has a wide range of polyphenols having antioxidant activity and its consumption has been linked with improved health benefits. Arsenic trioxide (ATO) is a very effective drug for the treatment of acute promyelocytic leukemia (APL) but it leads to cardiotoxicity mediated through alterations in various cardiac ion channels and by increasing the intracellular calcium level and reactive oxygen species (ROS). The aim of the present investigation was to study the effect of methanolic extract of apple peel (APME) and aqueous extract of apple peel (APAE) on ATO (5 μM) induced toxicity in the H9c2 cardiac myoblast cell line. We estimated the cellular status of innate antioxidant enzymes, level of ROS, mitochondrial superoxide, glutathione and intracellular calcium with ATO and apple peel extracts. Prior to the cell line based study, we had evaluated the antioxidant potential of apple peel extract by 1,1-diphenyl-2-picrylhydrazyl (DPPH), total reducing power (TRP), superoxide anion and hydroxyl radical scavenging activity, in addition to quantifying total phenolic and flavonoid content. Both the extracts showed considerable antioxidant activity in cell-free chemical assays. In addition, both APME and APAE prevented the alteration in antioxidant status induced by ATO in H9c2 cells. Significant differential alterations had been observed in the activity of lactate dehydrogenase, superoxide dismutase, catalase, glutathione, glutathione peroxidase, thioredoxin reductase, xanthine oxidase, calcium overload and caspase 3 activity with ATO. The overall result revealed the protective property of polyphenol-rich apple peel extract against ATO induced cardiac toxicity via its antioxidant activity.

  20. Monoamine Oxidase Inhibitors (MAOIs)

    Science.gov (United States)

    ... health-medications/index.shtml. Accessed May 16, 2016. Hirsch M, et al. Monoamine oxidase inhibitors (MAOIs) for ... www.uptodate.com/home. Accessed May 16, 2016. Hirsch M, et al. Discontinuing antidepressant medications in adults. ...

  1. Dietary polyphenol intake in Europe

    DEFF Research Database (Denmark)

    Zamora-Ros, Raul; Knaze, Viktoria; Rothwell, Joseph A

    2016-01-01

    were collected using a standardized 24-h dietary recall software administered to 36,037 adult subjects. Dietary data were linked with Phenol-Explorer, a database with data on 502 individual polyphenols in 452 foods and data on polyphenol losses due to cooking and food processing. RESULTS: Mean total....... The current cross-sectional analysis aimed at estimating dietary intakes of all currently known individual polyphenols and total intake per class and subclass, and to identify their main food sources in the European Prospective Investigation into Cancer and Nutrition cohort. METHODS: Dietary data at baseline...... polyphenol intake was the highest in Aarhus-Denmark (1786 mg/day in men and 1626 mg/day in women) and the lowest in Greece (744 mg/day in men and 584 mg/day in women). When dividing the subjects into three regions, the highest intake of total polyphenols was observed in the UK health-conscious group...

  2. Polyphenols and brain health

    Directory of Open Access Journals (Sweden)

    Vauzour David

    2017-03-01

    Full Text Available Accumulating evidence suggests that diet and lifestyle can play an important role in delaying the onset or halting the progression of age-related health disorders and to improve cognitive function. A growing number of dietary intervention studies in humans and animals and in particular those using polyphenol-rich diets have been proposed to exert a multiplicity of neuroprotective actions within the brain, including a potential to protect neurons against injury induced by neurotoxins, an ability to suppress neuroinflammation and a potential to promote memory, learning, and cognitive functions. These effects appear to be underpinned by two common processes. First, they are capable of interactions with critical protein and lipid kinase signalling cascades in the brain, leading to an inhibition of apoptosis triggered by neurotoxic species and to a promotion of neuronal survival and synaptic plasticity. Second, they induce beneficial effects on the vascular system, leading to changes in cerebrovascular blood flow capable of causing enhance vascularisation and neurogenesis, two events important in the maintenance of cognitive performances. Together, these processes act to maintain brain homeostasis and play important roles in neuronal stress adaptation and thus polyphenols might have the potential to prevent the progression of neurodegenerative pathologies.

  3. Review Paper: Polyphenolic Antioxidants and Neuronal Regeneration

    Directory of Open Access Journals (Sweden)

    Amin Ataie

    2016-05-01

    Full Text Available Many studies indicate that oxidative stress is involved in the pathophysiology of neurodegenerative diseases. Oxidative stress can induce neuronal damages, modulate intracellular signaling and ultimately leads to neuronal death by apoptosis or necrosis. To review antioxidants preventive effects on oxidative stress and neurodegenerative diseases we accumulated data from international medical journals and academic informations' sites. According to many studies, antioxidants could reduce toxic neuronal damages and many studies confirmed the efficacy of polyphenol antioxidants in fruits and vegetables to reduce neuronal death and to diminish oxidative stress. This systematic review showed the antioxidant activities of phytochemicals which play as natural neuroprotectives with low adverse effects against some neurodegenerative diseases as Parkinson or Alzheimer diseases.

  4. Review Paper: Polyphenolic Antioxidants and Neuronal Regeneration

    Directory of Open Access Journals (Sweden)

    Amin Ataie

    2016-04-01

    Full Text Available Many studies indicate that oxidative stress is involved in the pathophysiology of neurodegenerative diseases. Oxidative stress can induce neuronal damages, modulate intracellular signaling and ultimately leads to neuronal death by apoptosis or necrosis. To review antioxidants preventive effects on oxidative stress and neurodegenerative diseases we accumulated data from international medical journals and academic informations' sites. According to many studies, antioxidants could reduce toxic neuronal damages and many studies confirmed the efficacy of polyphenol antioxidants in fruits and vegetables to reduce neuronal death and to diminish oxidative stress. This systematic review showed the antioxidant activities of phytochemicals which play as natural neuroprotectives with low adverse effects against some neurodegenerative diseases as Parkinson or Alzheimer diseases.

  5. Polyphenols and Oxidative Stress in Atherosclerosis-Related Ischemic Heart Disease and Stroke

    Directory of Open Access Journals (Sweden)

    Yu-Chen Cheng

    2017-01-01

    Full Text Available Good nutrition could maintain health and life. Polyphenols are common nutrient mainly derived from fruits, vegetables, tea, coffee, cocoa, mushrooms, beverages, and traditional medicinal herbs. They are potential substances against oxidative-related diseases, for example, cardiovascular disease, specifically, atherosclerosis-related ischemic heart disease and stroke, which are health and economic problems recognized worldwide. In this study, we reviewed the risk factors for atherosclerosis, including hypertension, diabetes mellitus, hyperlipidemia, obesity, and cigarette smoking as well as the antioxidative activity of polyphenols, which could prevent the pathology of atherosclerosis, including endothelial dysfunction, low-density lipoprotein oxidation, vascular smooth muscle cell proliferation, inflammatory process by monocytes, macrophages or T lymphocytes, and platelet aggregation. The strong radical-scavenging properties of polyphenols would exhibit antioxidative and anti-inflammation effects. Polyphenols reduce ROS production by inhibiting oxidases, reducing the production of superoxide, inhibiting OxLDL formation, suppressing VSMC proliferation and migration, reducing platelet aggregation, and improving mitochondrial oxidative stress. Polyphenol consumption also inhibits the development of hypertension, diabetes mellitus, hyperlipidemia, and obesity. Despite the numerous in vivo and in vitro studies, more advanced clinical trials are necessary to confirm the efficacy of polyphenols in the treatment of atherosclerosis-related vascular diseases.

  6. Nutritional improvement of the endothelial control of vascular tone by polyphenols: role of NO and EDHF.

    Science.gov (United States)

    Schini-Kerth, Valérie B; Auger, Cyril; Kim, Jong-Hun; Etienne-Selloum, Nelly; Chataigneau, Thierry

    2010-05-01

    Numerous studies indicate that regular intake of polyphenol-rich beverages (red wine and tea) and foods (chocolate, fruit, and vegetables) is associated with a protective effect on the cardiovascular system in humans and animals. Beyond the well-known antioxidant properties of polyphenols, several other mechanisms have been shown to contribute to their beneficial cardiovascular effects. Indeed, both experimental and clinical studies indicate that polyphenols improve the ability of endothelial cells to control vascular tone. Experiments with isolated arteries have shown that polyphenols cause nitric oxide (NO)-mediated endothelium-dependent relaxations and increase the endothelial formation of NO. The polyphenol-induced NO formation is due to the redox-sensitive activation of the phosphatidylinositol3-kinase/Akt pathway leading to endothelial NO synthase (eNOS) activation subsequent to its phosphorylation on Ser 1177. Besides the phosphatidylinositol3-kinase/Akt pathway, polyphenols have also been shown to activate eNOS by increasing the intracellular free calcium concentration and by activating estrogen receptors in endothelial cells. In addition to causing a rapid and sustained activation of eNOS by phosphorylation, polyphenols can increase the expression level of eNOS in endothelial cells leading to an increased formation of NO. Moreover, the polyphenol-induced endothelium-dependent relaxation also involves endothelium-derived hyperpolarizing factor, besides NO, in several types of arteries. Altogether, polyphenols have the capacity to improve the endothelial control of vascular tone not only in several experimental models of cardiovascular diseases such as hypertension but also in healthy and diseased humans. Thus, these experimental and clinical studies highlight the potential of polyphenol-rich sources to provide vascular protection in health and disease.

  7. Antibacterial activity of polyphenolic fraction of Kombucha against Vibrio cholerae: targeting cell membrane.

    Science.gov (United States)

    Bhattacharya, D; Ghosh, D; Bhattacharya, S; Sarkar, S; Karmakar, P; Koley, H; Gachhui, R

    2018-02-01

    The present study was undertaken to determine the mechanism of antibacterial activity of a polyphenolic fraction, composed of mainly catechin and isorhamnetin, previously isolated from Kombucha, a 14-day fermented beverage of sugared black tea, against the enteropathogen Vibrio cholerae N16961. Bacterial growth was found to be seriously impaired by the polyphenolic fraction in a dose-dependent manner. Scanning Electron Microscopy demonstrated morphological alterations in bacterial cells when exposed to the polyphenolic fraction in a concentration-dependent manner. Permeabilization assays confirmed that the fraction disrupted bacterial membrane integrity in both time- and dose-dependent manners, which were proportional to the production of intracellular reactive oxygen species (ROS). Furthermore, each of the polyphenols catechin and isorhamnetin showed the ability to permeate bacterial cell membranes by generating oxidative stress, thereby suggesting their role in the antibacterial potential of Kombucha. Thus, the basic mechanism of antibacterial activity of the Kombucha polyphenolic fraction against V. cholerae involved bacterial membrane permeabilization and morphological changes, which might be due to the generation of intracellular ROS. To the best of our knowledge, this is the first report on the investigation of antibacterial mechanism of Kombucha, which is mostly attributed to its polyphenolic content. The emergence of multidrug-resistant Vibrio cholerae strains has hindered an efficient anti-Vibrio therapy. This study has demonstrated the membrane damage-mediated antibacterial mechanism of Kombucha, a popular fermented beverage of sugared tea, which is mostly attributed to its polyphenolic content. This study also implies the exploitation of Kombucha as a potential new source of bioactive polyphenols against V. cholerae. © 2017 The Society for Applied Microbiology.

  8. Isolated sulfite oxidase deficiency.

    Science.gov (United States)

    Rupar, C A; Gillett, J; Gordon, B A; Ramsay, D A; Johnson, J L; Garrett, R M; Rajagopalan, K V; Jung, J H; Bacheyie, G S; Sellers, A R

    1996-12-01

    Isolated sulfite oxidase (SO) deficiency is an autosomal recessively inherited inborn error of sulfur metabolism. In this report of a ninth patient the clinical history, laboratory results, neuropathological findings and a mutation in the sulfite oxidase gene are described. The data from this patient and previously published patients with isolated sulfite oxidase deficiency and molybdenum cofactor deficiency are summarized to characterize this rare disorder. The patient presented neonatally with intractable seizures and did not progress developmentally beyond the neonatal stage. Dislocated lenses were apparent at 2 months. There was increased urine excretion of sulfite and S-sulfocysteine and a decreased concentration of plasma cystine. A lactic acidemia was present for 6 months. Liver sulfite oxidase activity was not detectable but xanthine dehydrogenase activity was normal. The boy died of respiratory failure at 32 months. Neuropathological findings of cortical necrosis and extensive cavitating leukoencephalopathy were reminiscent of those seen in severe perinatal asphyxia suggesting an etiology of energy deficiency. A point mutation that resulted in a truncated protein missing the molybdenum-binding site has been identified.

  9. Role of dietary polyphenols in the management of peptic ulcer.

    Science.gov (United States)

    Farzaei, Mohammad Hosein; Abdollahi, Mohammad; Rahimi, Roja

    2015-06-07

    Peptic ulcer disease is a multifactorial and complex disease involving gastric and duodenal ulcers. Despite medical advances, the management of peptic ulcer and its complications remains a challenge, with high morbidity and death rates for the disease. An accumulating body of evidence suggests that, among a broad reach of natural molecules, dietary polyphenols with multiple biological mechanisms of action play a pivotal part in the management of gastric and duodenal ulcers. The current review confirmed that dietary polyphenols possess protective and therapeutic potential in peptic ulcer mediated by: improving cytoprotection, re-epithelialization, neovascularization, and angiogenesis; up-regulating tissue growth factors and prostaglandins; down-regulating anti-angiogenic factors; enhancing endothelial nitric oxide synthase-derived NO; suppressing oxidative mucosal damage; amplifying antioxidant performance, antacid, and anti-secretory activity; increasing endogenous mucosal defensive agents; and blocking Helicobacter pylori colonization associated gastric morphological changes and gastroduodenal inflammation and ulceration. In addition, anti-inflammatory activity due to down-regulation of proinflammatory cytokines and cellular and intercellular adhesion agents, suppressing leukocyte-endothelium interaction, inhibiting nuclear signaling pathways of inflammatory process, and modulating intracellular transduction and transcription pathways have key roles in the anti-ulcer action of dietary polyphenols. In conclusion, administration of a significant amount of dietary polyphenols in the human diet or as part of dietary supplementation along with conventional treatment can result in perfect security and treatment of peptic ulcer. Further well-designed preclinical and clinical tests are recommended in order to recognize higher levels of evidence for the confirmation of bioefficacy and safety of dietary polyphenols in the management of peptic ulcer.

  10. Antioxidant and antimicrobial activities of polyphenols from ...

    African Journals Online (AJOL)

    USER

    2010-05-17

    May 17, 2010 ... population depend on them as primary health care. (Akinyemi ... The mechanism of polyphenols toxicity against microbes may be related to ... and incubated at room temperature for 3 min. ..... polyphenols in copper foliage.

  11. Recent advances on tea polyphenols

    Science.gov (United States)

    Kanwar, Jyoti; Taskeen, Mujtaba; Mohammad, Imthiyaz; Huo, Congde; Chan, Tak Hang; Dou, Qing Ping

    2012-01-01

    Over the past decade many scientific and medical studies have focused on green tea for its long-purported health benefits. There is convincing evidence that tea is a cup of life. It has multiple preventive and therapeutic effects. This review thus focuses on the recent advances of tea polyphenols and their applications in the prevention and treatment of human cancers. Of the various polyphenols in tea, (−)-Epigallocatechin-3-gallate (EGCG) is the most abundant, and active compound studied in tea research. EGCG inhibits several molecular targets to inhibit cancer initiation and modulates several essential survival pathways to block cancer progression. Herein, we describe the various mechanisms of action of EGCG and also discuss previous and current ongoing clinical trials of EGCG and green tea polyphenols in different cancer types. PMID:22201858

  12. Dietary polyphenols and chromatin remodeling.

    Science.gov (United States)

    Russo, Gian Luigi; Vastolo, Viviana; Ciccarelli, Marco; Albano, Luigi; Macchia, Paolo Emidio; Ungaro, Paola

    2017-08-13

    Polyphenols are the most abundant phytochemicals in fruits, vegetables, and plant-derived beverages. Recent findings suggest that polyphenols display the ability to reverse adverse epigenetic regulation involved in pathological conditions, such as obesity, metabolic disorder, cardiovascular and neurodegenerative diseases, and various forms of cancer. Epigenetics, defined as heritable changes to the transcriptome, independent from those occurring in the genome, includes DNA methylation, histone modifications, and posttranscriptional gene regulation by noncoding RNAs. Sinergistically and cooperatively, these processes regulate gene expression by changing chromatin organization and DNA accessibility. Such induced epigenetic changes can be inherited during cell division, resulting in permanent maintenance of the acquired phenotype, but they may also occur throughout an individual life-course and may ultimately influence phenotypic outcomes (health and disease risk). In the last decade, a number of studies have shown that nutrients can affect metabolic traits by altering the structure of chromatin and directly regulate both transcription and translational processes. In this context, dietary polyphenol-targeted epigenetics becomes an attractive approach for disease prevention and intervention. Here, we will review how polyphenols, including flavonoids, curcuminoids, and stilbenes, modulate the establishment and maintenance of key epigenetic marks, thereby influencing gene expression and, hence, disease risk and health.

  13. Changes in polyphenol profile of dried apricots containing SO2 at various concentrations during storage.

    Science.gov (United States)

    Altındağ, Melek; Türkyılmaz, Meltem; Özkan, Mehmet

    2018-05-01

    Changes in polyphenols have important effects on the quality (especially color) and health benefits of dried apricots. SO 2 concentration, storage and the activities of polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) were factors which had significant effects on polyphenols. Polyphenol profile and activities of PPO and PAL in sulfured dried apricots (SDAs, 0, 451, 832, 2112 and 3241 mg SO 2 kg -1 ) were monitored during storage at 4, 20 and 30 °C for 379 days for the first time. Even the lowest SO 2 concentration (451 mg kg -1 ) was sufficient to inactivate PPO during the entire storage period. However, while SO 2 led to the increase in PAL activity of the samples (r = 0.767) before storage, PAL activities of SDAs decreased during storage. After 90 days of storage, PAL activity was determined in only non-sulfured dried apricots (NSDAs) and dried apricots containing 451 mg SO 2 kg -1 . Although the major polyphenol in NSDAs was epicatechin (611.4 mg kg -1 ), that in SDAs was chlorogenic acid (455-1508 mg kg -1 ), followed by epicatechin (0-426.8 mg kg -1 ), rutin (148.9-477.3 mg kg -1 ), ferulic acid (23.3-55.3 mg kg -1 ) and gallic acid (2.4-43.6 mg kg -1 ). After storage at 30 °C for 379 days, the major polyphenol in SDAs was gallic acid (706-2324 mg kg -1 ). However, the major polyphenol in NSDAs did not change after storage. The highest total polyphenol content was detected in SDAs containing 2112 mg SO 2 kg -1 and stored at 30 °C. To produce dried apricots having high polyphenol content, ∼2000 mg SO 2 kg -1 should be used. Low storage temperature (<30 °C) was not necessary for the protection of polyphenols. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Oxidase-based biocatalytic processes

    DEFF Research Database (Denmark)

    Ramesh, Hemalata; Woodley, John; Krühne, Ulrich

    interestingbiocatalystsbecause they use a mild oxidant (oxygen) as a substrateas opposed to their chemical counterparts which use strong oxidants such as permanganates. A class of oxidases calledmonoamine oxidases has been used as the central case study for the thesis. The rationale for choosing thissystemis that it has been...

  15. Dietary and plant polyphenols exert neuroprotective effects and improve cognitive function in cerebral ischemia.

    Science.gov (United States)

    Panickar, Kiran S; Jang, Saebyeol

    2013-08-01

    Cerebral ischemia is caused by an interruption of blood flow to the brain which generally leads to irreversible brain damage. Ischemic injury is associated with vascular leakage, inflammation, tissue injury, and cell death. Cellular changes associated with ischemia include impairment of metabolism, energy failure, free radical production, excitotoxicity, altered calcium homeostasis, and activation of proteases all of which affect brain functioning and also contribute to longterm disabilities including cognitive decline. Inflammation, mitochondrial dysfunction, increased oxidative/nitrosative stress, and intracellular calcium overload contribute to brain injury including cell death and brain edema. However, there is a paucity of agents that can effectively reduce cerebral damage and hence considerable attention has focused on developing newer agents with more efficacy and fewer side-effects. Polyphenols are natural compounds with variable phenolic structures and are rich in vegetables, fruits, grains, bark, roots, tea, and wine. Most polyphenols have antioxidant, anti-inflammatory, and anti-apoptotic properties and their protective effects on mitochondrial functioning, glutamate uptake, and regulating intracellular calcium levels in ischemic injury in vitro have been demonstrated. This review will assess the current status of the potential effects of polyphenols in reducing cerebral injury and improving cognitive function in ischemia in animal and human studies. In addition, the review will also examine available patents in nutrition and agriculture that relates to cerebral ischemic injury with an emphasis on plant polyphenols.

  16. In vitro antioxidant, lipoxygenase and xanthine oxidase inhibitory activities of fractions from Cienfuegosia digitata Cav., Sida alba L. and Sida acuta Burn f. (Malvaceae).

    Science.gov (United States)

    Konaté, K; Souza, A; Coulibaly, A Y; Meda, N T R; Kiendrebeogo, M; Lamien-Meda, A; Millogo-Rasolodimby, J; Lamidi, M; Nacoulma, O G

    2010-11-15

    In this study polyphenol content, antioxidant activity, lipoxygenase (LOX) and Xanthine Oxidase (XO) inhibitory effects of n-hexane, dichloromethane, ethyl acetate and n-butanol fractions of aqueous acetone extracts from S. alba L., S. acuta Burn f and Cienfuegosia digitata Cav. were investigated. The total phenolics, flavonoids, flavonols and total tannins were determined by spectrophotometric methods using Folin-ciocalteu, AlCl3 reagents and tannic acid, respectively. The antioxidant potential was evaluated using three methods: inhibition of free radical 2,2-diphenyl-1-picrylhydramzyl (DPPH), ABTS radical cation decolorization assay and Iron (III) to iron (II) reduction activity (FRAP). For enzymatic activity, lipoxygenase and xanthine oxidase inhibitory activities were used. This study shows a relationship between polyphenol contents, antioxidant and enzymatic activities. Present results showed that ethyl acetate and dichloromethane fractions elicit the highest polyphenol content, antioxidant and enzymatic activities.

  17. Contribution of Polyphenol Oxidation, Chlorophyll and Vitamin C Degradation to the Blackening of Piper nigrum L.

    Science.gov (United States)

    Gu, Fenglin; Huang, Feifei; Wu, Guiping; Zhu, Hongying

    2018-02-09

    Black pepper ( Piper nigrum L.) is the most widely used spice in the world. Blackening is considered to be beneficial and important in the processing of black pepper because it contributes to its color and flavor. The purpose of this paper is to investigate polyphenol oxidation as well as the chlorophyll and vitamin C (VC) degradation in the blackening of Piper nigrum L. Black pepper was produced by four methods, and changes in polyphenols, chlorophyll and VC were studied by high performance liquid chromatography (HPLC) and ultraviolet-visible and visible (UV-Vis) spectrophotometry. The results show that polyphenol oxidase activity significantly decreased during the preparation of black pepper, and the concentrations of phenolic compounds, VC, and chlorophyll a and b also significantly decreased. Polyphenol oxidation and chlorophyll and VC degradation contribute to the blackening. A crude extract of phenolic compounds from black pepper was prepared by the system solvent method. The greater the polarity of the extraction solvent, the higher the extraction rates of the phenolic compounds and the total phenol content. Pepper phenolic compounds were analyzed by HPLC analysis.

  18. Contribution of Polyphenol Oxidation, Chlorophyll and Vitamin C Degradation to the Blackening of Piper nigrum L.

    Directory of Open Access Journals (Sweden)

    Fenglin Gu

    2018-02-01

    Full Text Available Black pepper (Piper nigrum L. is the most widely used spice in the world. Blackening is considered to be beneficial and important in the processing of black pepper because it contributes to its color and flavor. The purpose of this paper is to investigate polyphenol oxidation as well as the chlorophyll and vitamin C (VC degradation in the blackening of Piper nigrum L. Black pepper was produced by four methods, and changes in polyphenols, chlorophyll and VC were studied by high performance liquid chromatography (HPLC and ultraviolet-visible and visible (UV-Vis spectrophotometry. The results show that polyphenol oxidase activity significantly decreased during the preparation of black pepper, and the concentrations of phenolic compounds, VC, and chlorophyll a and b also significantly decreased. Polyphenol oxidation and chlorophyll and VC degradation contribute to the blackening. A crude extract of phenolic compounds from black pepper was prepared by the system solvent method. The greater the polarity of the extraction solvent, the higher the extraction rates of the phenolic compounds and the total phenol content. Pepper phenolic compounds were analyzed by HPLC analysis.

  19. Inhibition of rat mammary microsomal oxidation of ethanol to acetaldehyde by plant polyphenols.

    Science.gov (United States)

    Maciel, María Eugenia; Castro, José Alberto; Castro, Gerardo Daniel

    2011-07-01

    We previously reported that the microsomal fraction from rat mammary tissue is able to oxidize ethanol to acetaldehyde, a mutagenic-carcinogenic metabolite, depending on the presence of NADPH and oxygen but not inhibited by carbon monoxide or other cytochrome P450 inhibitors. The process was strongly inhibited by diphenyleneiodonium, a known inhibitor of NADPH oxidase, and by nordihydroguaiaretic acid, an inhibitor of lipoxygenases. This led us to suggest that both enzymes could be involved. With the purpose of identifying natural compounds present in food with the ability to decrease the production of acetaldehyde in mammary tissue, in the present studies, several plant polyphenols having inhibitory effects on lipoxygenases and of antioxidant nature were tested as potential inhibitors of the rat mammary tissue microsomal pathway of ethanol oxidation. We included in the present screening study 32 polyphenols having ready availability and that were also tested against the rat mammary tissue cytosolic metabolism of ethanol to acetaldehyde. Several polyphenols were also able to inhibit the microsomal ethanol oxidation at concentrations as low was 10-50 μM. The results of these screening experiments suggest the potential of several plant polyphenols to prevent in vivo production and accumulation of acetaldehyde in mammary tissue.

  20. Peroxisomal Polyamine Oxidase and NADPH-Oxidase cross-talk for ROS homeostasis which affects respiration rate in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Efthimios A. Andronis

    2014-04-01

    Full Text Available Homeostasis of reactive oxygen species (ROS in the intracellular compartments is of critical importance as ROS have been linked with nearly all cellular processes and more importantly with diseases and aging. PAs are nitrogenous molecules with an evolutionary conserved role in the regulation of metabolic and energetic status of cells. Recent evidence also suggests that polyamines (PA are major regulators of ROS homeostasis. In Arabidopsis the backconversion of the PAs spermidine (Spd and spermine (Spm to putrescine (Put and Spd, respectively is catalyzed by two peroxisomal PA oxidases (AtPAO. However, the physiological role of this pathway remains largely elusive. Here we explore the role of peroxisomal PA backconversion and in particular that catalyzed by the highly expressed AtPAO3 in the regulation of ROS homeostasis and mitochondrial respiratory burst. Exogenous PAs exert an NADPH-oxidase dependent stimulation of oxygen consumption, with Spd exerting the strongest effect. This increase is attenuated by treatment with the NADPH-oxidase blocker diphenyleneiodonium iodide (DPI. Loss-of-function of AtPAO3 gene results to increased NADPH-oxidase-dependent production of superoxide anions (O2.-, but not H2O2, which activate the mitochondrial alternative oxidase pathway (AOX. On the contrary, overexpression of AtPAO3 results to an increased but balanced production of both H2O2 and O2.-. These results suggest that the ratio of O2.-/H2O2 regulates respiratory chain in mitochondria, with PA-dependent production of O2.- by NADPH-oxidase tilting the balance of electron transfer chain in favor of the AOX pathway. In addition, AtPAO3 seems to be an important component in the regulating module of ROS homeostasis, while a conserved role for PA backconversion and ROS across kingdoms is discussed.

  1. Cellular Targets of Dietary Polyphenol Resveratrol

    National Research Council Canada - National Science Library

    Wu, Joseph M

    2006-01-01

    To test the hypothesis that resveratrol, a grape derived polyphenol, exerts its chemopreventive properties against prostate cancer by interacting with specific cellular targets, denoted resveratrol targeting proteins (RTPs...

  2. Resveratrol protects vascular endothelial cells from high glucose-induced apoptosis through inhibition of NADPH oxidase activation-driven oxidative stress.

    Science.gov (United States)

    Chen, Feng; Qian, Li-Hua; Deng, Bo; Liu, Zhi-Min; Zhao, Ying; Le, Ying-Ying

    2013-09-01

    Hyperglycemia-induced oxidative stress has been implicated in diabetic vascular complications in which NADPH oxidase is a major source of reactive oxygen species (ROS) generation. Resveratrol is a naturally occurring polyphenol, which has vasoprotective effects in diabetic animal models and inhibits high glucose (HG)-induced oxidative stress in endothelial cells. We aimed to examine whether HG-induced NADPH oxidase activation and ROS production contribute to glucotoxicity to endothelial cells and the effect of resveratrol on glucotoxicity. Using a murine brain microvascular endothelial cell line bEnd3, we found that NADPH oxidase inhibitor (apocynin) and resveratrol both inhibited HG-induced endothelial cell apoptosis. HG-induced elevation of NADPH oxidase activity and production of ROS were inhibited by apocynin, suggesting that HG induces endothelial cell apoptosis through NADPH oxidase-mediated ROS production. Mechanistic studies revealed that HG upregulated NADPH oxidase subunit Nox1 but not Nox2, Nox4, and p22(phox) expression through NF-κB activation, which resulted in elevation of NADPH oxidase activity and consequent ROS production. Resveratrol prevented HG-induced endothelial cell apoptosis through inhibiting HG-induced NF-κB activation, NADPH oxidase activity elevation, and ROS production. HG induces endothelial cell apoptosis through NF-κB/NADPH oxidase/ROS pathway, which was inhibited by resveratrol. Our findings provide new potential therapeutic targets against brain vascular complications of diabetes. © 2013 John Wiley & Sons Ltd.

  3. Oxidases as Breast Cancer Oncogens

    National Research Council Canada - National Science Library

    Yeldandi, Anjana

    2000-01-01

    ...) in a non-tumorigenic human mammary epithelial cell line to ascertain whether oxidase overexpressing cells undergo transformation when exposed to substrate xanthine for XOX and uric acid for UOX...

  4. Glucose oxidase variants with improved properities

    OpenAIRE

    Fischer, Rainer; Ostafe, Raluca; Prodanovic, Radivoje

    2014-01-01

    Source: WO14173822A3 [EN] The technology provided herein relates to novel variants of microbial glucose oxidase with improved properties, more specifically to polypeptides having glucose oxidase activity as their major enzymatic activity; to nucleic acid molecules encoding said glucose oxidases; vectors and host cells containing the nucleic acids and methods for producing the glucose oxidase; compositions comprising said glucose oxidase; methods for the preparation and production of such enzy...

  5. NADPH Oxidases: Progress and Opportunities

    OpenAIRE

    San Martin, Alejandra; Griendling, Kathy K.

    2014-01-01

    From the initial discovery in 1999 that NADPH oxidases comprise a family of enzymes to our current focus on drug development to treat multiple pathologies related to this enzyme family, progress has been swift and impressive. We have expanded our understanding of the extent of the family, the basic enzymatic biochemistry, the multiple cellular functions controlled by NADPH oxidases, and their varied roles in physiology and diseases. We have developed numerous cell culture tools, animal models...

  6. Polyphenols as enzyme inhibitors in different degraded peat soils: Implication for microbial metabolism in rewetted peatlands

    Science.gov (United States)

    Zak, Dominik; Roth, Cyril; Gelbrecht, Jörg; Fenner, Nathalie; Reuter, Hendrik

    2015-04-01

    Recently, more than 30,000 ha of drained minerotrophic peatlands (= fens) in NE Germany were rewetted to restore their ecological functions. Due to an extended drainage history, a re-establishment of their original state is not expected in the short-term. Elevated concentrations of dissolved organic carbon, ammonium and phosphate have been measured in the soil porewater of the upper degraded peat layers of rewetted fens at levels of one to three orders higher than the values in pristine systems; an indicator of increased microbial activity in the upper degraded soil layers. On the other hand there is evidence that the substrate availability within the degraded peat layer is lowered since the organic matter has formerly been subject to intense decomposition over the decades of drainage and intense agricultural use of the areas. Previously however, it was suggested that inhibition of hydrolytic enzymes by polyphenolic substances is suspended during aeration of peat soils mainly due to the decomposition of the inhibiting polyphenols by oxidising enzymes such as phenol oxidase. Accordingly we hypothesised a lack of enzyme inhibiting polyphenols in degraded peat soils of rewetted fens compared to less decomposed peat of more natural fens. We collected both peat samples at the soil surface (0-20 cm) and fresh roots of dominating vascular plants and mosses (as peat parent material) from five formerly drained rewetted sites and five more natural sites of NE Germany and NW Poland. Less decomposed peat and living roots were used to obtain an internal standard for polyphenol analysis and to run enzyme inhibition tests. For all samples we determined the total phenolic contents and in addition we distinguished between the contents of hydrolysable and condensed tannic substances. From a methodical perspective the advantage of internal standards compared to the commercially available standards cyanidin chloride and tannic acid became apparent. Quantification with cyanidin or

  7. A Review of Polyphenolics in Oak Woods

    Directory of Open Access Journals (Sweden)

    Bo Zhang

    2015-03-01

    Full Text Available Polyphenolics, which are ubiquitous in plants, currently are among the most studied phytochemicals because of their perceptible chemical properties and antioxidant activity. Oak barrels and their alternatives, which are widely used in winemaking nowadays, contribute polyphenolics to wines and are thought to play crucial roles in the development of wines during aging. This study summarizes the detailed information of polyphenolics in oak woods and their products by examining their structures and discussing their chemical reactions during wine aging. This paper evaluates the most recent developments in polyphenolic chemistry by summarizing their extraction, separation, and their identification by the use of chromatographic and spectral techniques. In addition, this paper also introduces polyphenol bioactive ingredients in other plant foods.

  8. Polyphenol nanoformulations for cancer therapy: experimental evidence and clinical perspective

    Directory of Open Access Journals (Sweden)

    Davatgaran-Taghipour Y

    2017-04-01

    bioavailability. Different types of formulations have been designed for the improvement of bioavailability of these compounds, nanonization being one of the most notable approaches among them. This study aimed to review current data on the nanoformulations of natural polyphenols as chemopreventive and chemotherapeutic agents and to discuss their molecular anticancer mechanisms of action. Nanoformulations of natural polyphenols as bioactive agents, including resveratrol, curcumin, quercetin, epigallocatechin-3-gallate, chrysin, baicalein, luteolin, honokiol, silibinin, and coumarin derivatives, in a dose-dependent manner, result in better efficacy for the prevention and treatment of cancer. The impact of nanoformulation methods for these natural agents on tumor cells has gained wider attention due to improvement in targeted therapy and bioavailability, as well as enhancement of stability. Today, several nanoformulations are designed for delivery of polyphenolic compounds, including nanosuspensions, solid lipid nanoparticles, liposomes, gold nanoparticles, and polymeric nanoparticles, which have resulted in better antineoplastic activity, higher intracellular concentration of polyphenols, slow and sustained release of the drugs, and improvement of proapoptotic activity against tumor cells. To conclude, natural polyphenols demonstrate remarkable anticancer potential in pharmacotherapy; however, the obstacles in terms of their bioavailability in and toxicity to normal cells, as well as targeted drug delivery to malignant cells, can be overcome using nanoformulation-based technologies, which optimize the bioefficacy of these natural drugs. Keywords: natural products, flavonoid, anthocyanin, tumor, malignancy

  9. Flavonoid glycosides isolated from unique legume plant extracts as novel inhibitors of xanthine oxidase.

    Directory of Open Access Journals (Sweden)

    Chrysoula Spanou

    Full Text Available Legumes and the polyphenolic compounds present in them have gained a lot of interest due to their beneficial health implications. Dietary polyphenolic compounds, especially flavonoids, exert antioxidant properties and are potent inhibitors of xanthine oxidase (XO activity. XO is the main contributor of free radicals during exercise but it is also involved in pathogenesis of several diseases such as vascular disorders, cancer and gout. In order to discover new natural, dietary XO inhibitors, some polyphenolic fractions and pure compounds isolated from two legume plant extracts were tested for their effects on XO activity. The fractions isolated from both Vicia faba and Lotus edulis plant extracts were potent inhibitors of XO with IC(50 values range from 40-135 µg/mL and 55-260 µg/mL, respectively. All the pure polyphenolic compounds inhibited XO and their K(i values ranged from 13-767 µM. Ten of the compounds followed the non competitive inhibitory model whereas one of them was a competitive inhibitor. These findings indicate that flavonoid isolates from legume plant extracts are novel, natural XO inhibitors. Their mode of action is under investigation in order to examine their potential in drug design for diseases related to overwhelming XO action.

  10. Wine polyphenols: potential agents in neuroprotection.

    Science.gov (United States)

    Basli, Abdelkader; Soulet, Stéphanie; Chaher, Nassima; Mérillon, Jean-Michel; Chibane, Mohamed; Monti, Jean-Pierre; Richard, Tristan

    2012-01-01

    There are numerous studies indicating that a moderate consumption of red wine provides certain health benefits, such as the protection against neurodegenerative diseases. This protective effect is most likely due to the presence of phenolic compounds in wine. Wine polyphenolic compounds are well known for the antioxidant properties. Oxidative stress is involved in many forms of cellular and molecular deterioration. This damage can lead to cell death and various neurodegenerative disorders, such as Parkinson's or Alzheimer's diseases. Extensive investigations have been undertaken to determine the neuroprotective effects of wine-related polyphenols. In this review we present the neuroprotective abilities of the major classes of wine-related polyphenols.

  11. Wine Polyphenols: Potential Agents in Neuroprotection

    Science.gov (United States)

    Basli, Abdelkader; Soulet, Stéphanie; Chaher, Nassima; Mérillon, Jean-Michel; Chibane, Mohamed; Monti, Jean-Pierre; Richard, Tristan

    2012-01-01

    There are numerous studies indicating that a moderate consumption of red wine provides certain health benefits, such as the protection against neurodegenerative diseases. This protective effect is most likely due to the presence of phenolic compounds in wine. Wine polyphenolic compounds are well known for the antioxidant properties. Oxidative stress is involved in many forms of cellular and molecular deterioration. This damage can lead to cell death and various neurodegenerative disorders, such as Parkinson's or Alzheimer's diseases. Extensive investigations have been undertaken to determine the neuroprotective effects of wine-related polyphenols. In this review we present the neuroprotective abilities of the major classes of wine-related polyphenols. PMID:22829964

  12. Antioxidant and signal modulation properties of plant polyphenols in controlling vascular inflammation.

    Science.gov (United States)

    Kostyuk, Vladimir A; Potapovich, Alla I; Suhan, Tatyana O; de Luca, Chiara; Korkina, Liudmila G

    2011-05-11

    Oxidized low-density lipoproteins (oxLDL) play a critical role in the initiation of atherosclerosis through activation of inflammatory signaling. In the present work we investigated the role of antioxidant and signal modulation properties of plant polyphenols in controlling vascular inflammation. Significant decrease in intracellular NO level and superoxide overproduction was found in human umbilical vein endothelial cells (HUVEC) treated with oxLDL, but not with LDL. The redox imbalance was prevented by the addition of quercetin or resveratrol. Expression analysis of 14 genes associated with oxidative stress and inflammation revealed oxLDL-mediated up-regulation of genes specifically involved in leukocyte recruitment and adhesion. This up-regulation could be partially avoided by the addition of verbascoside or resveratrol, while treatment with quercetin resulted in a further increase in the expression of these genes. Lipopolysaccharide (LPS)-treated HUVEC were also used for the evaluation of anti-inflammatory potency of plant polyphenols. Significant differences between HUVEC treaded with oxLDL and LPS were found in both the expression pattern of inflammation-related genes and the effects of plant polyphenols on cellular responses. The present data indicate that plant polyphenols may affect vascular inflammation not only as antioxidants but also as modulators of inflammatory redox signaling pathways. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  13. Lysyl oxidase in colorectal cancer

    DEFF Research Database (Denmark)

    Cox, Thomas R; Erler, Janine T

    2013-01-01

    Colorectal cancer is the third most prevalent form of cancer worldwide and fourth-leading cause of cancer-related mortality, leading to ~600,000 deaths annually, predominantly affecting the developed world. Lysyl oxidase is a secreted, extracellular matrix-modifying enzyme previously suggested...... to act as a tumor suppressor in colorectal cancer. However, emerging evidence has rapidly implicated lysyl oxidase in promoting metastasis of solid tumors and in particular colorectal cancer at multiple stages, affecting tumor cell proliferation, invasion, and angiogenesis. This emerging research has...... advancements in the field of colorectal cancer....

  14. Multiple anti-inflammatory and anti-atherosclerotic properties of red wine polyphenolic extracts: differential role of hydroxycinnamic acids, flavonols and stilbenes on endothelial inflammatory gene expression.

    Science.gov (United States)

    Calabriso, Nadia; Scoditti, Egeria; Massaro, Marika; Pellegrino, Mariangela; Storelli, Carlo; Ingrosso, Ilaria; Giovinazzo, Giovanna; Carluccio, Maria Annunziata

    2016-03-01

    The aim of the study was to evaluate the vascular anti-inflammatory effects of polyphenolic extracts from two typical South Italy red wines, the specific contribution of individual polyphenols and the underlying mechanisms of action. Human endothelial cells were incubated with increasing concentrations (1-50 μg/mL) of Primitivo and Negroamaro polyphenolic extracts (PWPE and NWPE, respectively) or pure polyphenols (1-25 μmol/L), including hydroxycinnamic acids (p-coumaric, caffeic and caftaric acids), flavonols (kaempferol, quercetin, myricetin) or stilbenes (trans-resveratrol, trans-piceid) before stimulation with lipopolysaccharide. Through multiple assays, we analyzed the endothelial-monocyte adhesion, the endothelial expression of adhesion molecules (ICAM-1, VCAM-1 and E-Selectin), monocyte chemoattractant protein-1 (MCP-1) and macrophage colony-stimulating factor (M-CSF), as well as ROS intracellular levels and the activation of NF-κB and AP-1. Both PWPE and NWPE, already at 1 μg/mL, inhibited monocyte adhesion to stimulated endothelial cells, a key event in triggering vascular inflammation. They down-regulated the expression of adhesion molecules, ICAM-1, VCAM-1, E-Selectin, as well as MCP-1 and M-CSF, at mRNA and protein levels. All polyphenols reduced intracellular ROS, and everything, except caftaric acid, inhibited the endothelial expression of adhesion molecules and MCP-1, although with different potency. Flavonols and resveratrol significantly reduced also the endothelial expression and release of M-CSF. The decrease in endothelial inflammatory gene expression was related to the inhibition of NF-κB and AP-1 activation but not to intracellular oxidative stress. This study showed multiple anti-inflammatory and anti-atherosclerotic properties of red wine polyphenolic extracts and indentified specific bioactive polyphenols which could counteract inflammatory diseases including atherosclerosis.

  15. Red Wine Polyphenols for Cancer Prevention

    Science.gov (United States)

    He, Shan; Sun, Cuirong; Pan, Yuanjiang

    2008-01-01

    Conventional cancer therapies, the second leading cause of death worldwide, result in serious side effects and, at best, merely extend the patient's lifespan by a few years. Searching for effective prevention is of high priority in both basic and clinical sciences. In recent decades natural products have been considered to be an important source of cancer chemopreventive agents. Red wine polyphenols, which consisted of various powerful antioxidants such as flavonoids and stilbenes, have been implicated in cancer prevention and that promote human health without recognizable side effects. Since resveratrol, a major component of red wine polyphenols, has been studied and reviewed extensively for its chemopreventive activity to interfere with the multi-stage carcinogenesis, this review focuses on recent progress in studies on cancer chemopreventive activities of red wine polyphenol extracts and fractions as well as other red wine polyphenols, like procyanidin B5 analogues and myricetin. PMID:19325788

  16. Red Wine Polyphenols for Cancer Prevention

    Directory of Open Access Journals (Sweden)

    Yuanjiang Pan

    2008-05-01

    Full Text Available Conventional cancer therapies, the second leading cause of death worldwide, result in serious side effects and, at best, merely extend the patient's lifespan by a few years. Searching for effective prevention is of high priority in both basic and clinical sciences. In recent decades natural products have been considered to be an important source of cancer chemopreventive agents. Red wine polyphenols, which consisted of various powerful antioxidants such as flavonoids and stilbenes, have been implicated in cancer prevention and that promote human health without recognizable side effects. Since resveratrol, a major component of red wine polyphenols, has been studied and reviewed extensively for its chemopreventive activity to interfere with the multi-stage carcinogenesis, this review focuses on recent progress in studies on cancer chemopreventive activities of red wine polyphenol extracts and fractions as well as other red wine polyphenols, like procyanidin B5 analogues and myricetin.

  17. Dietary Polyphenols in the Prevention of Stroke

    Directory of Open Access Journals (Sweden)

    A. Tressera-Rimbau

    2017-01-01

    Full Text Available Polyphenols have an important protective role against a number of diseases, such as atherosclerosis, brain dysfunction, stroke, cardiovascular diseases, and cancer. Cardiovascular diseases are the number one cause of death worldwide: more people die annually from cardiovascular diseases than from any other cause. The most important behavioural risk factors of heart disease and stroke are unhealthy diet, physical inactivity, tobacco use, and excess alcohol intake. The dietary consumption of polyphenols has shown to be inversely associated with morbidity and mortality by cardio- and cerebrovascular diseases. It is well-known that the protective effects of polyphenols in vivo depend on the grade how they are extracted from food and on their intestinal absorption, metabolism, and biological action with target tissues. The aim of this review was to summarise the relation between polyphenols of different plant sources and stroke in human intervention studies, animal models, and in vitro studies.

  18. Dietary Polyphenols in the Prevention of Stroke

    Science.gov (United States)

    Eder, M.

    2017-01-01

    Polyphenols have an important protective role against a number of diseases, such as atherosclerosis, brain dysfunction, stroke, cardiovascular diseases, and cancer. Cardiovascular diseases are the number one cause of death worldwide: more people die annually from cardiovascular diseases than from any other cause. The most important behavioural risk factors of heart disease and stroke are unhealthy diet, physical inactivity, tobacco use, and excess alcohol intake. The dietary consumption of polyphenols has shown to be inversely associated with morbidity and mortality by cardio- and cerebrovascular diseases. It is well-known that the protective effects of polyphenols in vivo depend on the grade how they are extracted from food and on their intestinal absorption, metabolism, and biological action with target tissues. The aim of this review was to summarise the relation between polyphenols of different plant sources and stroke in human intervention studies, animal models, and in vitro studies. PMID:29204249

  19. Study of irradiation effect on curcuma polyphenols

    International Nuclear Information System (INIS)

    Rejeb, Imen

    2008-01-01

    The present study was carried out to evaluate the effect of gamma irradiation on curcumin (Curcuma Longa rhizome) component, particularly the polyphenolic fraction. Powdered rhizome was irradiated at 0, 5, 10 and 15 KGy (dose rate of 6 KGy / H). Polyphenolics were extracted and total polyphenols conent (TPC) was quantified using the Folin-Ciocalteau method. The irradiation effect was also evaluated by the HPLC technique. The chromatographic analysis showed that the irradiated and non-irradiated curcumin spectrum gave similar data. The antioxidant and antibacterial activities of the phenolic extracts were also assessed. the anti oxidative potential of the sample was evaluated using two radical scavenging methods with DPPH and ABTS. The antimicrobial analysis showed that the phenolic extracts of curcumin inhibited the growth of the studied microorganisms. Our results showed that irradiated samples were not affected in terms of polyphenols content and characteristics. (Author)

  20. Antioxidant and antimicrobial activities of polyphenols from ...

    African Journals Online (AJOL)

    the medicinal plants were screened for their antioxidant and antimicrobial activities against pathogenic micro organisms (Staphylococcus aureus, Streptococcus pyogenes, Esherichia coli and Candida albicans). The medicinal plants displayed different polyphenols contents and antioxidant activities. In addition, varying ...

  1. Polyphenols: skin photoprotection and inhibition of photocarcinogenesis.

    Science.gov (United States)

    Afaq, F; Katiyar, S K

    2011-12-01

    Polyphenols are a large family of naturally occurring plant products and are widely distributed in plant foods, such as, fruits, vegetables, nuts, flowers, bark and seeds, etc. These polyphenols contribute to the beneficial health effects of dietary products. Clinical and epidemiological studies suggest that exposure of the skin to environmental factors/pollutants, such as solar ultraviolet (UV) radiation induce harmful effects and leads to various skin diseases including the risk of melanoma and non-melanoma skin cancers. The incidence of non-melanoma skin cancer, comprising of squamous cell carcinoma and basal cell carcinoma, is a significant public health concern world-wide. Exposure of the skin to solar UV radiation results in inflammation, oxidative stress, DNA damage, dysregulation of cellular signaling pathways and immunosuppression thereby resulting in skin cancer. The regular intake of natural plant products, especially polyphenols, which are widely present in fruits, vegetables, dry legumes and beverages have gained considerable attention as protective agents against the adverse effects of UV radiation. In this article, we first discussed the impact of polyphenols on human health based on their structure-activity relationship and bioavailability. We then discussed in detail the photoprotective effects of some selected polyphenols on UV-induced skin inflammation, proliferation, immunosuppression, DNA damage and dysregulation of important cellular signaling pathways and their implications in skin cancer management. The selected polyphenols include: green tea polyphenols, pomegranate fruit extract, grape seed proanthocyanidins, resveratrol, silymarin, genistein and delphinidin. The new information on the mechanisms of action of these polyphenols supports their potential use in skin photoprotection and prevention of photocarcinogenesis in humans.

  2. Cocoa Polyphenols: Evidence from Epidemiological Studies.

    Science.gov (United States)

    Matsumoto, Chisa

    2018-01-01

    Accumulating evidence suggests potential preventive effects of chocolate/cocoa on the risk of cardio vascular disease (CVD). However, cocoa products also contain high levels of sugar and fat, which increase CVD risk factors. Even, the identity of the substance in chocolate/cocoa that has a favorable effect on CVD and CVD risk factors remains unclear, growing evidence from experimental studies suggests that cocoa polyphenols might be a major contributor to cardiovascular-protective effects. However, epidemiological studies, which are necessary to evaluate an association between the risk of CVD and cocoa polyphenol, remain sparse. We will discuss recent evidence regarding the association between cocoa polyphenol consumption and the risks of CVD and its risk factors by reviewing recent epidemiological studies. We shall also provide some guidance for patient counseling and will discuss the public health implications for recommending cocoa polyphenol consumption to prevent CVD. Epidemiological studies evaluating the association between cocoa polyphenol itself and the risk of CVD are sparse. However, evidence from limited epidemiological studies suggests that cocoa polyphenol consumption may lower the risk of CVD. Given the potential adverse effects of the consumption of cocoa products with high fat and sugar and the fact that the most appropriate dose of cocoa polyphenol for cardio-protective effects has not yet been established, health care providers should remain cautious about recommending cocoa/cocoa polyphenol consumption to their patients to reduce the risk of CVD, taking the characteristics of individual patients into careful consideration. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Lysyl oxidase in cancer research

    DEFF Research Database (Denmark)

    Perryman, Lara; Erler, Janine Terra

    2014-01-01

    Metastasis is the main reason for cancer-associated deaths and therapies are desperately needed to target the progression of cancer. Lysyl oxidase (LOX) plays a pivotal role in cancer progression, including metastasis, and is therefore is an attractive therapeutic target. In this review we...

  4. Season-controlled changes in biochemical constituents and oxidase enzyme activities in tomato (Lycopersicon esculentum Mill.).

    Science.gov (United States)

    Sen, Supatra; Mukherji, S

    2009-07-01

    Season-controlled changes in biochemical constituents viz. carotenoids (carotene and xanthophyll) and pectic substances along with IAA-oxidase and polyphenol oxidase (PPO) enzyme activities were estimated/assayed in leaves of Lycopersicon esculentum Mill. (tomato) in two developmental stages--pre-flowering (35 days after sowing) and post-flowering (75 days after sowing) in three different seasons--summer rainy and winter Carotenoid content along with pectic substances were highest in winter and declined significantly in summer followed by rainy i.e. winter > summer > rainy. Carotenoid content was significantly higher in the pre-flowering as compared to post-flowering in all three seasons while pectic substances increased in the post-flowering as compared to pre-flowering throughout the annual cycle. IAA oxidase and PPO enzyme activities were enhanced in rainy and decreased sharply in summer and winter i.e. rainy > summer > winter. Both the enzymes exhibited higher activity in the post-flowering stage as compared to pre-flowering in all three seasons. These results indicate winter to be the most favourable season for tomato plants while rainy season environmental conditions prove to be unfavourable (stressful) with diminished content of carotenoid and pectic substances and low activities of IAA oxidase and PPO, ultimately leading to poor growth and productivity.

  5. Boosting LPMO-driven lignocellulose degradation by polyphenol oxidase-activated lignin building blocks

    NARCIS (Netherlands)

    Frommhagen, Matthias; Mutte, Sumanth Kumar; Westphal, Adrie H.; Koetsier, Martijn J.; Hinz, Sandra W.A.; Visser, Jaap; Vincken, Jean Paul; Weijers, Dolf; Berkel, Van Willem J.H.; Gruppen, Harry; Kabel, Mirjam A.

    2017-01-01

    Background: Many fungi boost the deconstruction of lignocellulosic plant biomass via oxidation using lytic polysaccharide monooxygenases (LPMOs). The application of LPMOs is expected to contribute to ecologically friendly conversion of biomass into fuels and chemicals. Moreover, applications of

  6. Polyphenol fraction of extra virgin olive oil protects against endothelial dysfunction induced by high glucose and free fatty acids through modulation of nitric oxide and endothelin-1

    Directory of Open Access Journals (Sweden)

    Carolina Emilia Storniolo

    2014-01-01

    Full Text Available Epidemiological and clinical studies have reported that olive oil reduces the incidence of cardiovascular disease. However, the mechanisms involved in this beneficial effect have not been delineated. The endothelium plays an important role in blood pressure regulation through the release of potent vasodilator and vasoconstrictor agents such as nitric oxide (NO and endothelin-1 (ET-1, respectively, events that are disrupted in type 2 diabetes. Extra virgin olive oil contains polyphenols, compounds that exert a biological action on endothelial function. This study analyzes the effects of olive oil polyphenols on endothelial dysfunction using an in vitro model that simulates the conditions of type 2 diabetes. Our findings show that high glucose and linoleic and oleic acids decrease endothelial NO synthase phosphorylation, and consequently intracellular NO levels, and increase ET-1 synthesis by ECV304 cells. These effects may be related to the stimulation of reactive oxygen species production in these experimental conditions. Hydroxytyrosol and the polyphenol extract from extra virgin olive oil partially reversed the above events. Moreover, we observed that high glucose and free fatty acids reduced NO and increased ET-1 levels induced by acetylcholine through the modulation of intracellular calcium concentrations and endothelial NO synthase phosphorylation, events also reverted by hydroxytyrosol and polyphenol extract. Thus, our results suggest a protective effect of olive oil polyphenols on endothelial dysfunction induced by hyperglycemia and free fatty acids.

  7. Natural polyphenols: Influence on membrane transporters

    Directory of Open Access Journals (Sweden)

    Saad Abdulrahman Hussain

    2016-03-01

    Full Text Available Accumulated evidences have focused on the use of natural polyphenolic compounds as nutraceuticals, since they showed a wide range of bioactivities and exhibited protection against variety of age related disorders. Polyphenols have variable potencies to interact, and hence alter the activities of various transporter proteins, many of them classified as ATP-Binding Cassette transporters, like multidrug resistance protein (MDRP, and p-glycoprotein (P-gp. Some of the efflux transporters are generally linked with anticancer and antiviral drug resistance; in this context, polyphenols may be beneficial in modulating drug resistance by increasing the efficacy of anticancer and antiviral drugs. Additionally, these effects were implicated to explain the influence of dietary polyphenols on drug efficacy as result of food-drug interactions. However, limited data are available about the influence of these components on uptake transporters. Therefore, the objective of this article is to review the potential efficacies of polyphenols in modulating the functional integrity of uptake transporter proteins, including those terminated the effect of neurotransmitters, and their possible influence in neuropharmacology. [J Complement Med Res 2016; 5(1.000: 97-104

  8. Spirit drinks: a source of dietary polyphenols

    Directory of Open Access Journals (Sweden)

    Sanja Posavec

    2012-01-01

    Full Text Available There is a long tradition in the production of spirit drinks and using them in the human diet, especially in the Southeast European and Mediterranean regions. The objective of this study was to evaluate whether and which spirits can serve, and to what extent, as a source of biologically active compounds in the human diet. Polyphenolic compounds are biologically active compounds of fruits, vegetables and derived beverages, which have been implicated in their antioxidant activity. Therefore, the total polyphenol content (TPC and antioxidative properties of 46 spirit drinks and liqueurs produced in Croatia were examined. The total polyphenol content and antioxidant activity were estimated using spectrophotometric methods (Folin-Ciocalteu, DPPH and FRAP, while certain phenols were detected by the HPLC. It was established that spirit drinks aged in wooden casks, such as wine or plum brandy, contain polyphenols ranging from 40-90 mg GAE/L (gallic acid equivalents, whereas walnut or sour cherry liquors contain much more polyphenols ranging from 680-3360 mg GAE/L. The antioxidant activity of analyzed spirit drinks was in correlation with TPC. Walnut and sour cherry liqueur samples had very high antioxidant activity, within the range of those obtained with 1.26 mM Trolox-DPPH assay and 9.5 mM Trolox-FRAP assay.

  9. Plant Polyphenol Antioxidants and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    INES URQUIAGA

    2000-01-01

    Full Text Available In recent years there has been a remarkable increment in scientific articles dealing with oxidative stress. Several reasons justify this trend: knowledge about reactive oxygen and nitrogen species metabolism; definition of markers for oxidative damage; evidence linking chronic diseases and oxidative stress; identification of flavonoids and other dietary polyphenol antioxidants present in plant foods as bioactive molecules; and data supporting the idea that health benefits associated with fruits, vegetables and red wine in the diet are probably linked to the polyphenol antioxidants they contain.In this review we examine some of the evidence linking chronic diseases and oxidative stress, the distribution and basic structure of plant polyphenol antioxidants, some biological effects of polyphenols, and data related to their bioavailability and the metabolic changes they undergo in the intestinal lumen and after absorption into the organism.Finally, we consider some of the challenges that research in this area currently faces, with particular emphasis on the contributions made at the International Symposium "Biology and Pathology of Free Radicals: Plant and Wine Polyphenol Antioxidants" held July 29-30, 1999, at the Catholic University, Santiago, Chile and collected in this special issue of Biological Research

  10. Antioxidant and Antimicrobial Activity of Polyphenol Extracts from ...

    African Journals Online (AJOL)

    Methods: Polyphenol content was determined using spectrophotometric and High performance liquid ... Keywords: European cornel, Blackthorn, Wild blackberry, Polyphenols, Antioxidant, Antimicrobial. Tropical ... Acetonitrile, and acetic acid of HPLC-grade were ..... Anthocyanin Quantification and radical scavenging.

  11. Wine Polyphenols: Potential Agents in Neuroprotection

    Directory of Open Access Journals (Sweden)

    Abdelkader Basli

    2012-01-01

    Full Text Available There are numerous studies indicating that a moderate consumption of red wine provides certain health benefits, such as the protection against neurodegenerative diseases. This protective effect is most likely due to the presence of phenolic compounds in wine. Wine polyphenolic compounds are well known for the antioxidant properties. Oxidative stress is involved in many forms of cellular and molecular deterioration. This damage can lead to cell death and various neurodegenerative disorders, such as Parkinson’s or Alzheimer’s diseases. Extensive investigations have been undertaken to determine the neuroprotective effects of wine-related polyphenols. In this review we present the neuroprotective abilities of the major classes of wine-related polyphenols.

  12. Influence of diabetes on the pharmacokinetic behavior of natural polyphenols.

    Science.gov (United States)

    Xiao, Jianbo; Högger, Petra

    2014-01-01

    The development of food fortified with polyphenols and polyphenol-rich foods represents a novel approach to prevent or attenuate type 2 diabetes. It has been reported that type 2 diabetes may affect the pharmacokinetics of various drugs in several animal models. There is powerful evidence linking dietary polyphenols consumption with the risk factors defining type 2 diabetes, even if some opposite results occurred. This mini-review summarizes important advances on diabetes-associated changes in pharmacokinetics of natural polyphenols. The pharmacokinetic behavior between drugs and dietary polyphenols probably may be different due to (i) Ingested dose/amount per day. The dietary polyphenol intake per day is much higher than that of clinical drugs; (ii) Complexity of the components. Clinical drugs are well-characterized and typically small molecules. However, the polyphenols in diet are unimaginably complex; (iii) Interaction with food proteins. Although the effects of food proteins on the bioavailability of polyphenols are still not examined in much detail, direct binding interactions of polyphenols to proteins always occur; (iv) The most common polyphenols in the human diet have a low intrinsic activity and are poorly absorbed from the intestine, highly metabolized, or rapidly eliminated. Although there is very limited information available so far, it is proposed that type 2 diabetes influences the pharmacokinetic behavior of dietary polyphenols including: i) competition of glucose with polyphenols regarding binding to plasma proteins; ii) weakened non-covalent interaction affinities of plasma proteins for natural polyphenols due to protein glycation in type II diabetes; iii) the enhanced clearance of polyphenols in type 2 diabetes. An understanding of diabetes-associated changes in absorption, distribution, metabolism, elimination and bioactivities of natural polyphenols as well as the mechanism of the variability should lead to the improvement of the benefits of

  13. Cancer Prevention by Tocopherols and Tea Polyphenols

    Science.gov (United States)

    Yang, Chung S.; Li, Guangxun; Yang, Zhihong; Guan, Fei; Chen, Amber; Ju, Jihyeung

    2013-01-01

    Tocopherols (vitamin E) and tea polyphenols have been reported to have cancer preventive activities. Large-scale human trials with high doses of alpha-tocopherol, however, have produced disappointing results. This review presents data showing that γ- and δ-tocopherols inhibit colon, lung, mammary and prostate carcinogenesis in animal models, whereas α-tocopherol is ineffective in animal and human studies. Possible mechanisms of action are discussed. A broad cancer preventive activity of green tea polyphenols has been demonstrated in animal models, and many mechanisms have been proposed. The cancer preventive activity of green tea in humans, however, has not been conclusively demonstrated and remains to be further investigated. PMID:23403075

  14. The impact of polyphenols on chondrocyte growth and survival: a preliminary report

    Directory of Open Access Journals (Sweden)

    Salvador Fernández-Arroyo

    2015-10-01

    Full Text Available Background: Imbalances in the functional binding of fibroblast growth factors (FGFs to their receptors (FGFRs have consequences for cell proliferation and differentiation that in chondrocytes may lead to degraded cartilage. The toxic, proinflammatory, and oxidative response of cytokines and FGFs can be mitigated by dietary polyphenols. Objective: We explored the possible effects of polyphenols in the management of osteoarticular diseases using a model based on the transduction of a mutated human FGFR3 (G380R in murine chondrocytes. This mutation is present in most cases of skeletal dysplasia and is responsible for the overexpression of FGFR3 that, in the presence of its ligand, FGF9, results in toxic effects leading to altered cellular growth. Design: Different combinations of dietary polyphenols derived from plant extracts were assayed in FGFR3 (G380R mutated murine chondrocytes, exploring cell survival, chloride efflux, extracellular matrix (ECM generation, and grade of activation of mitogen-activated protein kinases. Results: Bioactive compounds from Hibiscus sabdariffa reversed the toxic effects of FGF9 and restored normal growth, suggesting a probable translation to clinical requests in humans. Indeed, these compounds activated the intracellular chloride efflux, increased ECM generation, and stimulated cell proliferation. The inhibition of mitogen-activated protein kinase phosphorylation was interpreted as the main mechanism governing these beneficial effects. Conclusions: These findings support the rationale behind the encouragement of the development of drugs that repress the overexpression of FGFRs and suggest the dietary incorporation of supplementary nutrients in the management of degraded cartilage.

  15. of polyphenolic compounds in Ilex Sp.

    Directory of Open Access Journals (Sweden)

    Zwyrzykowska Anna

    2015-11-01

    Full Text Available Natural compounds are an important source of desired biological activity which help to improve nutritional status, enhance productivity and bring many health benefits. The leaves of the Ilex paraguariensis (Aquifoliaceae are used for preparing a beverage known as yerba mate and represent a proven source of natural polyphenols which are known to foster biological activity with the emphasis on antioxidant properties. In present work we focused on the polyphenolic content of air-dried leaves of Ilex aquifolium L., Ilex aquifolium ‘Argentea Mariginata’, Ilex meserveae ‘Blue Angel’, and a commercially available mate as the reference product. Liquid chromatography combined with mass spectrometry (HPLC and LC-MS and thin layer chromatography (TLC, were used to establish polyphenolic substances content in aqueous methanolic extracts obtained from the biological matter. Up to 20 polyphenolic compounds were identified in the extracts, including rutin, quinic acid and its caffeoyl esters, i.e. chlorogenic acid and its isomers as well as dicaffeoyl derivatives. We took chlorogenic acid and rutin as reference compounds to quantify their levels in the extracts. It was determined that in all tested plants, high levels of these antioxidants were present. This led us to the conclusion that their leaves might serve as valuable food additives.

  16. T3SS effector VopL inhibits the host ROS response, promoting the intracellular survival of Vibrio parahaemolyticus.

    Directory of Open Access Journals (Sweden)

    Marcela de Souza Santos

    2017-06-01

    Full Text Available The production of antimicrobial reactive oxygen species by the nicotinamide dinucleotide phosphate (NADPH oxidase complex is an important mechanism for control of invading pathogens. Herein, we show that the gastrointestinal pathogen Vibrio parahaemolyticus counteracts reactive oxygen species (ROS production using the Type III Secretion System 2 (T3SS2 effector VopL. In the absence of VopL, intracellular V. parahaemolyticus undergoes ROS-dependent filamentation, with concurrent limited growth. During infection, VopL assembles actin into non-functional filaments resulting in a dysfunctional actin cytoskeleton that can no longer mediate the assembly of the NADPH oxidase at the cell membrane, thereby limiting ROS production. This is the first example of how a T3SS2 effector contributes to the intracellular survival of V. parahaemolyticus, supporting the establishment of a protective intracellular replicative niche.

  17. Polyphenols produced during red wine ageing.

    Science.gov (United States)

    Brouillard, R; George, F; Fougerousse, A

    1997-01-01

    Over the past few years, it has been accepted that a moderate red wine consumption is a factor beneficial to human health. Indeed, people of France and Italy, the two major wine-producing European countries, eat a lot of fatty foods but suffer less from fatal heart strokes than people in North-America or in the northern regions of Europe, where wine is not consumed on a regular basis. For a time, ethanol was thought to be the "good" chemical species hiding behind what is known as the "French paradox". Researchers now have turned their investigations towards a family of natural substances called "polyphenols", which are only found in plants and are abundant in grapes. It is well known that these molecules behave as radical scavengers and antioxidants, and it has been demonstrated that they can protect cholesterol in the LDL species from oxidation, a process thought to be at the origin of many fatal heart attacks. However, taken one by one, it remains difficult to demonstrate which are the best polyphenols as far as their antioxidant activities are concerned. The main obstacle in that kind of research is not the design of the chemical and biological tests themselves, but surprisingly enough, the limited access to chemically pure and structurally elucidated polyphenolic compounds. In this article, particular attention will be paid to polyphenols of red wine made from Vitis vinifera cultivars. With respect to the "French paradox", we address the following question: are wine polyphenolic compounds identical to those found in grapes (skin, pulp and seed), or are there biochemical modifications specifically taking place on the native flavonoids when a wine ages? Indeed, structural changes occur during wine conservation, and one of the most studied of those changes concerns red wine colour evolution, called "wine ageing". As a wine ages, it has been demonstrated that the initially present grape pigments slowly turn into new more stable red pigments. That phenomenon goes on

  18. Anticancer Efficacy of Polyphenols and Their Combinations

    Directory of Open Access Journals (Sweden)

    Aleksandra Niedzwiecki

    2016-09-01

    Full Text Available Polyphenols, found abundantly in plants, display many anticarcinogenic properties including their inhibitory effects on cancer cell proliferation, tumor growth, angiogenesis, metastasis, and inflammation as well as inducing apoptosis. In addition, they can modulate immune system response and protect normal cells against free radicals damage. Most investigations on anticancer mechanisms of polyphenols were conducted with individual compounds. However, several studies, including ours, have indicated that anti-cancer efficacy and scope of action can be further enhanced by combining them synergistically with chemically similar or different compounds. While most studies investigated the anti-cancer effects of combinations of two or three compounds, we used more comprehensive mixtures of specific polyphenols and mixtures of polyphenols with vitamins, amino acids and other micronutrients. The mixture containing quercetin, curcumin, green tea, cruciferex, and resveratrol (PB demonstrated significant inhibition of the growth of Fanconi anemia head and neck squamous cell carcinoma and dose-dependent inhibition of cell proliferation, matrix metalloproteinase (MMP-2 and -9 secretion, cell migration and invasion through Matrigel. PB was found effective in inhibition of fibrosarcoma HT-1080 and melanoma A2058 cell proliferation, MMP-2 and -9 expression, invasion through Matrigel and inducing apoptosis, important parameters for cancer prevention. A combination of polyphenols (quercetin and green tea extract with vitamin C, amino acids and other micronutrients (EPQ demonstrated significant suppression of ovarian cancer ES-2 xenograft tumor growth and suppression of ovarian tumor growth and lung metastasis from IP injection of ovarian cancer A-2780 cells. The EPQ mixture without quercetin (NM also has shown potent anticancer activity in vivo and in vitro in a few dozen cancer cell lines by inhibiting tumor growth and metastasis, MMP-2 and -9 secretion, invasion

  19. Polyphenol levels in human urine after intake of six different polyphenol-rich beverages.

    Science.gov (United States)

    Ito, Hideyuki; Gonthier, Marie-Paule; Manach, Claudine; Morand, Christine; Mennen, Louise; Rémésy, Christian; Scalbert, Augustin

    2005-10-01

    Dietary polyphenols are suggested to participate in the prevention of CVD and cancer. It is essential for epidemiological studies to be able to compare intake of the main dietary polyphenols in populations. The present paper describes a fast method suitable for the analysis of polyphenols in urine, selected as potential biomarkers of intake. This method is applied to the estimation of polyphenol recovery after ingestion of six different polyphenol-rich beverages. Fifteen polyphenols including mammalian lignans (enterodiol and enterolactone), several phenolic acids (chlorogenic, caffeic, m-coumaric, gallic, and 4-O-methylgallic acids), phloretin and various flavonoids (catechin, epicatechin, quercetin, isorhamnetin, kaempferol, hesperetin, and naringenin) were simultaneously quantified in human urine by HPLC coupled with electrospray ionisation mass-MS (HPLC-electrospray-tandem mass spectrometry) with a run time of 6 min per sample. The method has been validated with regard to linearity, precision, and accuracy in intra- and inter-day assays. It was applied to urine samples collected from nine volunteers in the 24 h following consumption of either green tea, a grape-skin extract, cocoa beverage, coffee, grapefruit juice or orange juice. Levels of urinary excretion suggest that chlorogenic acid, gallic acid, epicatechin, naringenin or hesperetin could be used as specific biomarkers to evaluate the consumption of coffee, wine, tea or cocoa, and citrus juices respectively.

  20. A broad distribution of the alternative oxidase in microsporidian parasites.

    Directory of Open Access Journals (Sweden)

    Bryony A P Williams

    2010-02-01

    Full Text Available Microsporidia are a group of obligate intracellular parasitic eukaryotes that were considered to be amitochondriate until the recent discovery of highly reduced mitochondrial organelles called mitosomes. Analysis of the complete genome of Encephalitozoon cuniculi revealed a highly reduced set of proteins in the organelle, mostly related to the assembly of iron-sulphur clusters. Oxidative phosphorylation and the Krebs cycle proteins were absent, in keeping with the notion that the microsporidia and their mitosomes are anaerobic, as is the case for other mitosome bearing eukaryotes, such as Giardia. Here we provide evidence opening the possibility that mitosomes in a number of microsporidian lineages are not completely anaerobic. Specifically, we have identified and characterized a gene encoding the alternative oxidase (AOX, a typically mitochondrial terminal oxidase in eukaryotes, in the genomes of several distantly related microsporidian species, even though this gene is absent from the complete genome of E. cuniculi. In order to confirm that these genes encode functional proteins, AOX genes from both A. locustae and T. hominis were over-expressed in E. coli and AOX activity measured spectrophotometrically using ubiquinol-1 (UQ-1 as substrate. Both A. locustae and T. hominis AOX proteins reduced UQ-1 in a cyanide and antimycin-resistant manner that was sensitive to ascofuranone, a potent inhibitor of the trypanosomal AOX. The physiological role of AOX microsporidia may be to reoxidise reducing equivalents produced by glycolysis, in a manner comparable to that observed in trypanosomes.

  1. Exploring flavin-containing carbohydrate oxidases

    NARCIS (Netherlands)

    Ferrari, Alessandro Renato

    2017-01-01

    Oxidases are enzymes capable of removing one or more electrons from their substrate and transfer them to molecular oxygen, forming hydrogen peroxide. Due to their high regio- and enantioselectivity, their use is preferred over traditional organic chemistry methods. Among the oxidases, flavoprotein

  2. The terminal oxidases of Paracoccus denitrificans

    NARCIS (Netherlands)

    de Gier, J.-W.; Lübben, M; Reijnders, W N; Tipker, C A; Slotboom, D.J.; van Spanning, R J; Stouthamer, A.H.; van der Oost, J.

    Three distinct types of terminal oxidases participate in the aerobic respiratory pathways of Paracoccus denitrificans. Two alternative genes encoding subunit I of the aa3-type cytochrome c oxidase have been isolated before, namely ctaDI and ctaDII. Each of these genes can be expressed separately to

  3. Ultrafine carbon particles promote rotenone-induced dopamine neuronal loss through activating microglial NADPH oxidase

    International Nuclear Information System (INIS)

    Wang, Yinxi; Liu, Dan; Zhang, Huifeng; Wang, Yixin; Wei, Ling; Liu, Yutong; Liao, Jieying; Gao, Hui-Ming; Zhou, Hui

    2017-01-01

    Background: Atmospheric ultrafine particles (UFPs) and pesticide rotenone were considered as potential environmental risk factors for Parkinson's disease (PD). However, whether and how UFPs alone and in combination with rotenone affect the pathogenesis of PD remains largely unknown. Methods: Ultrafine carbon black (ufCB, a surrogate of UFPs) and rotenone were used individually or in combination to determine their roles in chronic dopaminergic (DA) loss in neuron-glia, and neuron-enriched, mix-glia cultures. Immunochemistry using antibody against tyrosine hydroxylase was performed to detect DA neuronal loss. Measurement of extracellular superoxide and intracellular reactive oxygen species (ROS) were performed to examine activation of NADPH oxidase. Genetic deletion and pharmacological inhibition of NADPH oxidase and MAC-1 receptor in microglia were employed to examine their role in DA neuronal loss triggered by ufCB and rotenone. Results: In rodent midbrain neuron-glia cultures, ufCB and rotenone alone caused neuronal death in a dose-dependent manner. In particularly, ufCB at doses of 50 and 100 μg/cm 2 induced significant loss of DA neurons. More importantly, nontoxic doses of ufCB (10 μg/cm 2 ) and rotenone (2 nM) induced synergistic toxicity to DA neurons. Microglial activation was essential in this process. Furthermore, superoxide production from microglial NADPH oxidase was critical in ufCB/rotenone-induced neurotoxicity. Studies in mix-glia cultures showed that ufCB treatment activated microglial NADPH oxidase to induce superoxide production. Firstly, ufCB enhanced the expression of NADPH oxidase subunits (gp91 phox , p47 phox and p40 phox ); secondly, ufCB was recognized by microglial surface MAC-1 receptor and consequently promoted rotenone-induced p47 phox and p67 phox translocation assembling active NADPH oxidase. Conclusion: ufCB and rotenone worked in synergy to activate NADPH oxidase in microglia, leading to oxidative damage to DA neurons. Our

  4. Ultrafine carbon particles promote rotenone-induced dopamine neuronal loss through activating microglial NADPH oxidase

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yinxi; Liu, Dan; Zhang, Huifeng; Wang, Yixin [Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, 100191 (China); Wei, Ling [Beijing Center for Physical & Chemical Analysis, Beijing 100089 (China); Liu, Yutong [School of Life Science, Beijing Normal University, Beijing 100875 (China); Liao, Jieying [Department of Translational Medicine, Xiamen Institute of Rare Earth Materials, Chinese Academy of Sciences, Xiamen 361024 (China); Gao, Hui-Ming [Model Animal Research Center of Nanjing University, Nanjing 211800 (China); Zhou, Hui, E-mail: hardhui@gmail.com [Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, 100191 (China)

    2017-05-01

    Background: Atmospheric ultrafine particles (UFPs) and pesticide rotenone were considered as potential environmental risk factors for Parkinson's disease (PD). However, whether and how UFPs alone and in combination with rotenone affect the pathogenesis of PD remains largely unknown. Methods: Ultrafine carbon black (ufCB, a surrogate of UFPs) and rotenone were used individually or in combination to determine their roles in chronic dopaminergic (DA) loss in neuron-glia, and neuron-enriched, mix-glia cultures. Immunochemistry using antibody against tyrosine hydroxylase was performed to detect DA neuronal loss. Measurement of extracellular superoxide and intracellular reactive oxygen species (ROS) were performed to examine activation of NADPH oxidase. Genetic deletion and pharmacological inhibition of NADPH oxidase and MAC-1 receptor in microglia were employed to examine their role in DA neuronal loss triggered by ufCB and rotenone. Results: In rodent midbrain neuron-glia cultures, ufCB and rotenone alone caused neuronal death in a dose-dependent manner. In particularly, ufCB at doses of 50 and 100 μg/cm{sup 2} induced significant loss of DA neurons. More importantly, nontoxic doses of ufCB (10 μg/cm{sup 2}) and rotenone (2 nM) induced synergistic toxicity to DA neurons. Microglial activation was essential in this process. Furthermore, superoxide production from microglial NADPH oxidase was critical in ufCB/rotenone-induced neurotoxicity. Studies in mix-glia cultures showed that ufCB treatment activated microglial NADPH oxidase to induce superoxide production. Firstly, ufCB enhanced the expression of NADPH oxidase subunits (gp91{sup phox}, p47{sup phox} and p40{sup phox}); secondly, ufCB was recognized by microglial surface MAC-1 receptor and consequently promoted rotenone-induced p47{sup phox} and p67{sup phox} translocation assembling active NADPH oxidase. Conclusion: ufCB and rotenone worked in synergy to activate NADPH oxidase in microglia, leading to

  5. Stochastic models of intracellular transport

    KAUST Repository

    Bressloff, Paul C.; Newby, Jay M.

    2013-01-01

    mechanisms for intracellular transport: passive diffusion and motor-driven active transport. Diffusive transport can be formulated in terms of the motion of an overdamped Brownian particle. On the other hand, active transport requires chemical energy, usually

  6. Introducing inducible fluorescent split cholesterol oxidase to mammalian cells.

    Science.gov (United States)

    Chernov, Konstantin G; Neuvonen, Maarit; Brock, Ivonne; Ikonen, Elina; Verkhusha, Vladislav V

    2017-05-26

    Cholesterol oxidase (COase) is a bacterial enzyme catalyzing the first step in the biodegradation of cholesterol. COase is an important biotechnological tool for clinical diagnostics and production of steroid drugs and insecticides. It is also used for tracking intracellular cholesterol; however, its utility is limited by the lack of an efficient temporal control of its activity. To overcome this we have developed a regulatable fragment complementation system for COase cloned from Chromobacterium sp. The enzyme was split into two moieties that were fused to FKBP (FK506-binding protein) and FRB (rapamycin-binding domain) pair and split GFP fragments. The addition of rapamycin reconstituted a fluorescent enzyme, termed split GFP-COase, the fluorescence level of which correlated with its oxidation activity. A rapid decrease of cellular cholesterol induced by intracellular expression of the split GFP-COase promoted the dissociation of a cholesterol biosensor D4H from the plasma membrane. The process was reversible as upon rapamycin removal, the split GFP-COase fluorescence was lost, and cellular cholesterol levels returned to normal. These data demonstrate that the split GFP-COase provides a novel tool to manipulate cholesterol in mammalian cells. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. The microglial NADPH oxidase complex as a source of oxidative stress in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Landreth Gary E

    2006-11-01

    Full Text Available Abstract Alzheimer's disease is the most common cause of dementia in the elderly, and manifests as progressive cognitive decline and profound neuronal loss. The principal neuropathological hallmarks of Alzheimer's disease are the senile plaques and the neurofibrillary tangles. The senile plaques are surrounded by activated microglia, which are largely responsible for the proinflammatory environment within the diseased brain. Microglia are the resident innate immune cells in the brain. In response to contact with fibrillar beta-amyloid, microglia secrete a diverse array of proinflammatory molecules. Evidence suggests that oxidative stress emanating from activated microglia contribute to the neuronal loss characteristic of this disease. The source of fibrillar beta-amyloid induced reactive oxygen species is primarily the microglial nicotinamide adenine dinucleotide phosphate (NADPH oxidase. The NADPH oxidase is a multicomponent enzyme complex that, upon activation, produces the highly reactive free radical superoxide. The cascade of intracellular signaling events leading to NADPH oxidase assembly and the subsequent release of superoxide in fibrillar beta-amyloid stimulated microglia has recently been elucidated. The induction of reactive oxygen species, as well as nitric oxide, from activated microglia can enhance the production of more potent free radicals such as peroxynitrite. The formation of peroxynitrite causes protein oxidation, lipid peroxidation and DNA damage, which ultimately lead to neuronal cell death. The elimination of beta-amyloid-induced oxidative damage through the inhibition of the NADPH oxidase represents an attractive therapeutic target for the treatment of Alzheimer's disease.

  8. Wine Polyphenols: Potential Agents in Neuroprotection

    OpenAIRE

    Basli, Abdelkader; Soulet, Stéphanie; Chaher, Nassima; Mérillon, Jean-Michel; Chibane, Mohamed; Monti, Jean-Pierre; Richard, Tristan

    2012-01-01

    There are numerous studies indicating that a moderate consumption of red wine provides certain health benefits, such as the protection against neurodegenerative diseases. This protective effect is most likely due to the presence of phenolic compounds in wine. Wine polyphenolic compounds are well known for the antioxidant properties. Oxidative stress is involved in many forms of cellular and molecular deterioration. This damage can lead to cell death and various neurodegenerative disorders, su...

  9. Red Wine Polyphenols for Cancer Prevention

    OpenAIRE

    He, Shan; Sun, Cuirong; Pan, Yuanjiang

    2008-01-01

    Conventional cancer therapies, the second leading cause of death worldwide, result in serious side effects and, at best, merely extend the patient's lifespan by a few years. Searching for effective prevention is of high priority in both basic and clinical sciences. In recent decades natural products have been considered to be an important source of cancer chemopreventive agents. Red wine polyphenols, which consisted of various powerful antioxidants such as flavonoids and stilbenes, have been ...

  10. Galloylation of polyphenols alters their biological activity

    Czech Academy of Sciences Publication Activity Database

    Karas, D.; Ulrichová, J.; Valentová, Kateřina

    2017-01-01

    Roč. 105, JUL 2017 (2017), s. 223-240 ISSN 0278-6915 R&D Projects: GA MŠk(CZ) LD15082; GA MŠk(CZ) LD15084; GA MŠk(CZ) LO1304 Grant - others:GA ČR(CZ) GAP303/12/G163 Program:GA Institutional support: RVO:61388971 Keywords : Polyphenols * Gallic acid * Galloylation Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 3.778, year: 2016

  11. Polyphenols, Antioxidants and the Sympathetic Nervous System.

    Science.gov (United States)

    Bruno, Rosa Maria; Ghiadoni, Lorenzo

    2018-01-01

    A high dietary intake of polyphenols has been associated with a reduced cardiovascular mortality, due to their antioxidant properties. However, growing evidence suggests that counteracting oxidative stress in cardiovascular disease might also reduce sympathetic nervous system overactivity. This article reviews the most commonly used techniques to measure sympathetic activity in humans; the role of sympathetic activation in the pathophysiology of cardiovascular diseases; current evidence demonstrating that oxidative stress is involved in the regulation of sympathetic activity and how antioxidants and polyphenols might counteract sympathetic overactivity, particularly focusing on preliminary data from human studies. The main mechanisms by which polyphenols are cardioprotective are related to the improvement of vascular function and their anti-atherogenic effect. Furthermore, a blood pressure-lowering effect was consistently demonstrated in randomized controlled trials in humans, when the effect of flavonoid-rich foods, such as tea and chocolate, was tested. More recent studies suggest that inhibition of sympathetic overactivity might be one of the mechanisms by which these substances exert their cardioprotective effects. Indeed, an increased adrenergic traffic to the vasculature is a major mechanism of disease in a number of cardiovascular and extra-cardiac diseases, including hypertension, obesity, metabolic syndrome and heart failure. A considerable body of evidence, mostly from experimental studies, support the hypothesis that reactive oxygen species might exert sympathoexcitatory effects both at the central and at the peripheral level. Accordingly, supplementation with antioxidants might reduce adrenergic overdrive to the vasculature and blunt cardiovascular reactivity to stress. While supplementation with "classical" antioxidants such as ROS-scavengers has many limitations, increasing the intake of polyphenol-rich foods seems to be a promising novel therapeutic

  12. Anti-Oxidative Polyphenolic Compounds of Cocoa.

    Science.gov (United States)

    Nabavi, Seyed F; Sureda, Antoni; Daglia, Maria; Rezaei, Parizad; Nabavi, Seyed M

    2015-01-01

    Oxidative stress plays a key role in the pathogenesis of different serious chronic diseases such as cancer, diabetes, cardiovascular and neurodegenerative disorders, etc. Recent research has been focused on the beneficial role of dietary antioxidants against oxidative stress both under in vitro and in vivo conditions. Theobroma cacao L. (cacao tree) is an evergreen tree which is native to South America. It is a plant of great economic importance and its seeds are commonly used to produce cocoa powder and chocolate. In addition to its uses in food industry, cocoa is a rich source of polyphenolic antioxidants. There is a plethora of in vitro and in vivo studies that report cocoa antioxidant capacity. The protective activity of cocoa seems to be due to its phytochemical constituents, especially catechins. However, bioavailability of cocoa polyphenolic constituents following oral administration is very low (nanomolar concentrations). In the present paper, we critically reviewed the available literature on the antioxidant and free radical scavenging activities of cocoa and its polyphenolic constituents. In addition to these, we provide brief information about cultivation, phytochemistry, bioavailability and clinical impacts of cocoa.

  13. Immobilization of oxidases and their analytical applications

    International Nuclear Information System (INIS)

    Yasinzai, M.

    2007-01-01

    Immobilized enzymes are replacing their soluble counter-parts in nearly every field of application. These enzyme modifications have evolved from a research curiosity into an entire branch of Biotechnology. An immobilization method for flavin containing oxidases and their use in flow injection system is described. An electrochemical detector for H/sub 2/O/sub 2/ is assembled which is used effectively for the determination of glucose using more common glucose oxidase and the simultaneous determination of sugars. The combination of oxidases with hydrolases have been used for the determination of maltose and starch. (author)

  14. Insecticide resistance and intracellular proteases.

    Science.gov (United States)

    Wilkins, Richard M

    2017-12-01

    Pesticide resistance is an example of evolution in action with mechanisms of resistance arising from mutations or increased expression of intrinsic genes. Intracellular proteases have a key role in maintaining healthy cells and in responding to stressors such as pesticides. Insecticide-resistant insects have constitutively elevated intracellular protease activity compared to corresponding susceptible strains. This increase was shown for some cases originally through biochemical enzyme studies and subsequently putatively by transcriptomics and proteomics methods. Upregulation and expression of proteases have been characterised in resistant strains of some insect species, including mosquitoes. This increase in proteolysis results in more degradation products (amino acids) of intracellular proteins. These may be utilised in the resistant strain to better protect the cell from stress. There are changes in insect intracellular proteases shortly after insecticide exposure, suggesting a role in stress response. The use of protease and proteasome inhibitors or peptide mimetics as synergists with improved application techniques and through protease gene knockdown using RNA interference (possibly expressed in crop plants) may be potential pest management strategies, in situations where elevated intracellular proteases are relevant. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  15. Plant polyphenols and their anti-cariogenic properties: a review

    OpenAIRE

    Ferrazzano, G.F.; Amato, I.; Ingenito, A.; Zarrelli, A.; Pinto, G.; Pollio, A.

    2011-01-01

    Polyphenols constitute one of the most common groups of substances in plants. Polyphenolic compounds have been reported to have a wide range of biological activities, many of which are related to their conventional antioxidant action; however, increasing scientific knowledge has highlighted their potential activity in preventing oral disease, including the prevention of tooth decay. The aim of this review is to show the emerging findings on the anti-cariogenic properties of polyphenols, which...

  16. Cocoa and Dark Chocolate Polyphenols: From Biology to Clinical Applications

    OpenAIRE

    Thea Magrone; Matteo Antonio Russo; Emilio Jirillo; Emilio Jirillo

    2017-01-01

    It is well known that cocoa and dark chocolate possess polyphenols as major constituents whose dietary consumption has been associated to beneficial effects. In fact, cocoa and dark chocolate polyphenols exert antioxidant and anti-inflammatory activities switching on some important signaling pathways such as toll-like receptor 4/nuclear factor κB/signal transducer and activator of transcription. In particular, cocoa polyphenols induce release of nitric oxide (NO) through activation of endothe...

  17. Polyphenols from artichoke heads (Cynara cardunculus (L.) subsp. scolymus Hayek): in vitro bio-accessibility, intestinal uptake and bioavailability.

    Science.gov (United States)

    D'Antuono, Isabella; Garbetta, Antonella; Linsalata, Vito; Minervini, Fiorenza; Cardinali, Angela

    2015-04-01

    Artichoke is a rich source of health promoting compounds such as polyphenols, important for their pharmaceutical and nutritional properties. In this study, the potential for bioavailability of the artichoke polyphenols was estimated by using both in vitro digestion and Caco-2 human intestinal cell models. In vitro digestive recoveries (bio-accessibility) were found to be 55.8% for total artichoke phenolics and in particular, 70.0% for chlorogenic acid, 41.3% for 3,5-O-dicaffeoylquinic acid, and 50.3% for 1,5-O-dicaffeoylquinic acid, highlighting potential sensitivity of these compounds to gastric and small intestinal digestive conditions. Uptake of artichoke polyphenols was rapid with peak accumulation occurring after 30 min with an efficiency of 0.16%, according to the poor uptake of dietary polyphenols. Some compounds, such as coumaric acid, caffeic acid and caffeic acid derivatives, were also detected in the basolateral side assuming extra and intracellular esterase activities on chlorogenic acid. Only apigenin-7-O-glucoside was transported through the Caco-2 monolayer demonstrating its bioavailability to the extent of 1.15% at 60 min. In addition, permeability coefficient (Papp = 2.29 × 10(-5) cm s(-1)), involving apical to basolateral transport of apigenin 7-O-glucoside, was calculated to facilitate estimation of transport through the Caco-2 monolayer. Finally, the mono and dicaffeoylquinic acids present in artichoke heads exert an antioxidant activity on the human low density lipoprotein system correlated to their chemical structure. In conclusion, the utilized in vitro models, although not fully responding to the morphological and physiological features of human in vivo conditions, could be a useful tool for investigating mechanistic effects of polyphenols released from the food matrix.

  18. The antioxidant properties, cytotoxicity and monoamine oxidase ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... Department of Pharmaceutical Chemistry, North-West University, Private Bag X6001, Potchefstroom 2520, ..... on the inhibition of the catabolism of serotonin, .... Structure of human monoamine oxidase B, a drug target for.

  19. Vanillyl-alcohol oxidase, a tasteful biocatalyst

    NARCIS (Netherlands)

    Heuvel, van den R.H.H.; Fraaije, M.W.; Mattevi, A.; Laane, C.; Berkel, van W.J.H.

    2001-01-01

    The covalent flavoenzyme vanillyl-alcohol oxidase (VAO) is a versatile biocatalyst. It converts a wide range of phenolic compounds by catalysing oxidation, deamination, demethylation, dehydrogenation and hydroxylation reactions. The production of natural vanillin, 4-hydroxybenzaldehyde, coniferyl

  20. Genetics Home Reference: isolated sulfite oxidase deficiency

    Science.gov (United States)

    ... and Management Resources (1 link) GeneReview: Isolated Sulfite Oxidase Deficiency General Information from MedlinePlus (5 links) Diagnostic Tests Drug Therapy Genetic Counseling Palliative Care Surgery and ...

  1. Cocoa Polyphenols and Inflammatory Markers of Cardiovascular Disease

    Science.gov (United States)

    Khan, Nasiruddin; Khymenets, Olha; Urpí-Sardà, Mireia; Tulipani, Sara; Garcia-Aloy, Mar; Monagas, María; Mora-Cubillos, Ximena; Llorach, Rafael; Andres-Lacueva, Cristina

    2014-01-01

    Epidemiological studies have demonstrated the beneficial effect of plant-derived food intake in reducing the risk of cardiovascular disease (CVD). The potential bioactivity of cocoa and its polyphenolic components in modulating cardiovascular health is now being studied worldwide and continues to grow at a rapid pace. In fact, the high polyphenol content of cocoa is of particular interest from the nutritional and pharmacological viewpoints. Cocoa polyphenols are shown to possess a range of cardiovascular-protective properties, and can play a meaningful role through modulating different inflammatory markers involved in atherosclerosis. Accumulated evidence on related anti-inflammatory effects of cocoa polyphenols is summarized in the present review. PMID:24566441

  2. Optimization of extraction of polyphenols from Sorghum Moench ...

    African Journals Online (AJOL)

    phenolic acid were assayed using high performance liquid (HPLC). ... quantification of antioxidants and phenolic compounds from Sorghum M, ... Keywords: Response surface methodology, Sorghum moench, Polyphenols, Antioxidants.

  3. Effect of complex polyphenols on colon carcinogenesis.

    Science.gov (United States)

    Caderni, G; Remy, S; Cheynier, V; Morozzi, G; Dolara, P

    1999-06-01

    Complex polyphenols and tannins from wine (WCPT) are being considered increasingly as potential cancer chemopreventive agents, since epidemiological studies suggest that populations consuming a high amount of polyphenols in the diet may have a lower incidence of some types of cancer. We studied the effect of WCPT on a series of parameters related to colon carcinogenesis in rats. WCPT were administered to F344 rats at a dose of 14 or 57 mg/kg/d, mixed with the diet. The higher dose is about ten times the exposure to polyphenols of a moderate drinker of red wine. In rats treated with WCPT, we measured fecal bile acids and long chain fatty acids, colon mucosa cell proliferation, apoptosis and, after administration of colon carcinogens, the number and size of aberrant crypt foci (ACF) and nuclear aberrations. Colon mucosa proliferation was not varied by chronic administration (90 d) of WCPT (14 or 57 mg/kg/d). The highest dose of WCPT decreased the number of cells in the colon crypts, but did not increase apoptosis. WCPT (57 mg/kg) administered before or after the administration of azoxymethane (AOM) did not vary the number or multiplicity of ACF in the colon. The number of nuclear aberrations (NA) in colon mucosa was studied after administration of 1,2-dimethylhydrazine (DMH) and 2-amino-3-methylimidazo (4,5-f)quinoline (IQ), colon-specific carcinogens which require metabolic activation. The effect of DMH and IQ was not varied by pre-feeding WCPT (57 mg/kg) for 10 d. Similarly, the levels of total, secondary bile acids and long chain fatty acids did not varied significantly in animals fed WCPT for 90 d. WCPT administration does not influence parameters related to colon carcinogenesis in the rat.

  4. Impact of polyphenolic extracts on resistance to fungal ...

    African Journals Online (AJOL)

    Our results lend support of the creation of varieties bean high in polyphenols, which act as natural preservatives and bio-effective agents, and offer an alternative to chemical agents for protection of harvested beans in storage structures. Keywords: Polyphenols, antifungal activity, dry bean. African Journal of Biotechnology ...

  5. Polyphenols from cocoa and vascular health-a critical review.

    Science.gov (United States)

    Rimbach, Gerald; Melchin, Mona; Moehring, Jennifer; Wagner, Anika E

    2009-11-20

    Cocoa is a rich source of dietary polyphenols. In vitro as well as cell culture data indicate that cocoa polyphenols may exhibit antioxidant and anti-inflammatory, as well as anti-atherogenic activity. Several molecular targets (e.g., nuclear factor kappa B, endothelial nitric oxide synthase, angiotensin converting enzyme) have been recently identified which may partly explain potential beneficial cardiovascular effects of cocoa polyphenols. However cocoa polyphenol concentrations, as used in many cell culture studies, are not physiologically achievable. Bioavailability studies indicate that plasma concentrations of cocoa polyphenols following dietary intake are low and in the nanomolar range. Human studies regarding the effect of cocoa polyphenols on vascular health are often underpowered and lack a rigorous study design. If dietary cocoa polyphenol intake is due to chocolate its high energy content needs to be taken into account. In order to determine potential health benefits of cocoa polyphenols large scale, long term, randomized, placebo controlled studies, (ideally with a cross-over design) as well as prospective studies are warranted.

  6. Metabolic fate of polyphenols in the human superorganism

    NARCIS (Netherlands)

    van Duynhoven, J.; Vaughan, E. E.; Jacobs, D.M.; Kemperman, R. A.; van Velzen, E.J.J.; Gross, G.; Roger, L. C.; Possemiers, S.; Smilde, A.K.; Doré, J.; Westerhuis, J.A.; van der Wiele, T.

    2011-01-01

    Dietary polyphenols are components of many foods such as tea, fruit, and vegetables and are associated with several beneficial health effects although, so far, largely based on epidemiological studies. The intact forms of complex dietary polyphenols have limited bioavailability, with low circulating

  7. Effect of fermentation and drying on cocoa polyphenols.

    Science.gov (United States)

    Albertini, Barbara; Schoubben, Aurélie; Guarnaccia, Davide; Pinelli, Filippo; Della Vecchia, Mirco; Ricci, Maurizio; Di Renzo, Gian Carlo; Blasi, Paolo

    2015-11-18

    Cocoa seed polyphenols have demonstrated interesting beneficial effects in humans. Most polyphenols contained in fresh seeds are chemically modified during fermentation, drying, and cocoa powder or chocolate production. The improvement of these procedures to obtain a high-polyphenol-content cocoa is highly desirable. To this aim, a field investigation on the effect of fermentation and natural drying on fine flavor National cocoa (cacao Nacional) was performed. Cocoa seeds were fermented for 6 days and, every day, samples were sun-dried and analyzed for polyphenol content and antioxidant power. During the first 2 days of fermentation, Folin-Ciocalteu and FRAP tests evidenced a significant reduction of polyphenol content and antioxidant capacity, respectively. Changes during the following days of fermentation were less significant. Epicatechin, the most studied member of the catechin family, followed a similar pathway of degradation. Data confirmed the high impact of fermentation and drying on cocoa seed polyphenols. Fermentation and drying are, on the one hand, necessary to obtain cocoa flavor and palatability but, on the other hand, are responsible for greatly compromising polyphenol content. To obtain high-polyphenol-content cocoa, the existing fermentation, drying, and manufacturing protocols should be scientifically reviewed to understand and modify the critical steps.

  8. Towards functional effects of polyphenols : modulation of energy metabolism revealed

    NARCIS (Netherlands)

    Boer, de V.C.J.

    2007-01-01

    A diet rich in fruits and vegetables contains high levels of polyphenols (up to 1 gram per day). Epidemiological studies suggest that a high dietary intake of selected polyphenols can be protective against development of cardiovascular heart diseases in humans. In addition, mechanistic studies

  9. Antioxidant and Antimicrobial Activity of Polyphenol Extracts from ...

    African Journals Online (AJOL)

    Purpose: To assess the antioxidant and antimicrobial activities of polyphenolic extracts of three wild red wild berry fruit species from Southeast Serbia, viz, European cornel (Cornus mas), blackthorn (Prunus spinosa L.) and wild blackberry (Rubus fruticosus). Methods: Polyphenol content was determined using ...

  10. Population-based nutrikinetic modeling of polyphenol exposure

    NARCIS (Netherlands)

    van Velzen, E.J.J.; Westerhuis, J.A.; Grün, C.H.; Jacobs, D.M.; Eilers, P.H.C.; Mulder, Th.P.; Foltz, M.; Garczarek, U.; Kemperman, R.; Vaughan, E. E.; van Duynhoven, J.P.M.; Smilde, A.K.

    2014-01-01

    The beneficial health effects of fruits and vegetables have been attributed to their polyphenol content. These compounds undergo many bioconversions in the body. Modeling polyphenol exposure of humans upon intake is a prerequisite for understanding the modulating effect of the food matrix and the

  11. Polyphenols from Cocoa and Vascular Health—A Critical Review

    Directory of Open Access Journals (Sweden)

    Anika E. Wagner

    2009-09-01

    Full Text Available Cocoa is a rich source of dietary polyphenols. In vitro as well as cell culture data indicate that cocoa polyphenols may exhibit antioxidant and anti-inflammatory, as well as anti-atherogenic activity. Several molecular targets (e.g., nuclear factor kappa B, endothelial nitric oxide synthase, angiotensin converting enzyme have been recently identified which may partly explain potential beneficial cardiovascular effects of cocoa polyphenols. However cocoa polyphenol concentrations, as used in many cell culture studies, are not physiologically achievable. Bioavailability studies indicate that plasma concentrations of cocoa polyphenols following dietary intake are low and in the nanomolar range. Human studies regarding the effect of cocoa polyphenols on vascular health are often underpowered and lack a rigorous study design. If dietary cocoa polyphenol intake is due to chocolate its high energy content needs to be taken into account. In order to determine potential health benefits of cocoa polyphenols large scale, long term, randomized, placebo controlled studies, (ideally with a cross-over design as well as prospective studies are warranted.

  12. Dietary Polyphenols and Their Biological Significance

    Directory of Open Access Journals (Sweden)

    Hongxiang Lou

    2007-09-01

    Full Text Available Dietary polyphenols represent a wide variety of compounds that occur in fruits,vegetables, wine, tea, extra virgin olive oil, chocolate and other cocoa products. They aremostly derivatives and/or isomers of flavones, isoflavones, flavonols, catechins andphenolic acids, and possess diverse biological properties such as antioxidant, antiapoptosis,anti-aging, anticarcinogen, anti-inflammation, anti-atherosclerosis, cardiovascularprotection, improvement of the endothelial function, as well as inhibition of angiogenesisand cell proliferation activity. Most of these biological actions have been attributed to theirintrinsic reducing capabilities. They may also offer indirect protection by activatingendogenous defense systems and by modulating cellular signaling processes such asnuclear factor-kappa B (NF-кB activation, activator protein-1(AP-1 DNA binding,glutathione biosynthesis, phosphoinositide 3 (PI3-kinase/protein kinase B (Akt pathway,mitogen-activated protein kinase (MAPK proteins [extracellular signal-regulated proteinkinase (ERK, c-jun N-terminal kinase (JNK and P38 ] activation, and the translocationinto the nucleus of nuclear factor erythroid 2 related factor 2 (Nrf2. This paper covers themost recent literature on the subject, and describes the biological mechanisms of action andprotective effects of dietary polyphenols.

  13. Activity of Polyphenolic Compounds against Candida glabrata

    Directory of Open Access Journals (Sweden)

    Ricardo Salazar-Aranda

    2015-09-01

    Full Text Available Opportunistic mycoses increase the morbidity and mortality of immuno-compromised patients. Five Candida species have been shown to be responsible for 97% of worldwide cases of invasive candidiasis. Resistance of C. glabrata and C. krusei to azoles has been reported, and new, improved antifungal agents are needed. The current study was designed to evaluatethe activity of various polyphenolic compounds against Candida species. Antifungal activity was evaluated following the M27-A3 protocol of the Clinical and Laboratory Standards Institute, and antioxidant activity was determined using the DPPH assay. Myricetin and baicalein inhibited the growth of all species tested. This effect was strongest against C. glabrata, for which the minimum inhibitory concentration (MIC value was lower than that of fluconazole. The MIC values against C. glabrata for myricitrin, luteolin, quercetin, 3-hydroxyflavone, and fisetin were similar to that of fluconazole. The antioxidant activity of all compounds was confirmed, and polyphenolic compounds with antioxidant activity had the greatest activity against C. glabrata. The structure and position of their hydroxyl groups appear to influence their activity against C. glabrata.

  14. Immunomodulating Activity of Aronia melanocarpa Polyphenols

    Directory of Open Access Journals (Sweden)

    Giang T. T. Ho

    2014-06-01

    Full Text Available The immunomodulating effects of isolated proanthocyanidin-rich fractions, procyanidins C1, B5 and B2 and anthocyanins of Aronia melanocarpa were investigated. In this work, the complement-modulating activities, the inhibitory activities on nitric oxide (NO production in LPS-induced RAW 264.7 macrophages and effects on cell viability of these polyphenols were studied. Several of the proanthocyanidin-rich fractions, the procyanidins C1, B5 and B2 and the cyanidin aglycone possessed strong complement-fixing activities. Cyanidin 3-glucoside possessed stronger activity than the other anthocyanins. Procyanidins C1, B5 and B2 and proanthocyanidin-rich fractions having an average degree of polymerization (PD of 7 and 34 showed inhibitory activities on NO production in LPS-stimulated RAW 264.7 mouse macrophages. All, except for the fraction containing proanthocyanidins with PD 34, showed inhibitory effects without affecting cell viability. This study suggests that polyphenolic compounds of A. melanocarpa may have beneficial effects as immunomodulators and anti-inflammatory agents.

  15. Beer Polyphenols and Menopause: Effects and Mechanisms—A Review of Current Knowledge

    Science.gov (United States)

    Sandoval-Ramírez, Berner Andrée; M. Lamuela-Raventós, Rosa; Estruch, Ramon; Sasot, Gemma; Doménech, Monica

    2017-01-01

    Beer is one of the most frequently consumed fermented beverages in the world, and it has been part of the human diet for thousands of years. Scientific evidence obtained from the development of new techniques of food analysis over the last two decades suggests that polyphenol intake derived from moderate beer consumption may play a positive role in different health outcomes including osteoporosis and cardiovascular risk and the relief of vasomotor symptoms, which are commonly experienced during menopause and are an important reason why women seek medical care during this period; here, we review the current knowledge regarding moderate beer consumption and its possible effects on menopausal symptoms. The effect of polyphenol intake on vasomotor symptoms in menopause may be driven by the direct interaction of the phenolic compounds present in beer, such as 8-prenylnaringenin, 6-prenylnaringenin, and isoxanthohumol, with intracellular estrogen receptors that leads to the modulation of gene expression, increase in sex hormone plasma concentrations, and thus modulation of physiological hormone imbalance in menopausal women. Since traditional hormone replacement therapies increase health risks, alternative, safer treatment options are needed to alleviate menopausal symptoms in women. The present work aims to review the current data on this subject. PMID:28904736

  16. Polyphenols as dietary supplements: A double-edged sword

    Directory of Open Access Journals (Sweden)

    Keith R Martin

    2009-12-01

    Full Text Available Keith R Martin, Christy L AppelNutrition Program, Healthy Lifestyles Research Center, College of Nursing and Health Innovation, Arizona State University, Mesa, AZ, USAAbstract: Increased consumption of fruits and vegetables is associated with a lower risk of chronic disease such as cardiovascular disease, some forms of cancer, and neurodegeneration. Pro-oxidant-induced oxidative stress contributes to the pathogenesis of numerous chronic diseases and, as such, dietary antioxidants can quench and/or retard such processes. Dietary polyphenols, ie, phenolic acids and flavonoids, are a primary source of antioxidants for humans and are derived from plants including fruits, vegetables, spices, and herbs. Based on compelling evidence regarding the health effects of polyphenol-rich foods, new dietary supplements and polyphenol-rich foods are being developed for public use. Consumption of such products can increase dietary polyphenol intake and subsequently plasma concentrations beyond expected levels associated with dietary consumption and potentially confer additional health benefits. Furthermore, bioavailability can be modified to further increase absorption and ultimately plasma concentrations of polyphenols. However, the upper limit for plasma concentrations of polyphenols before the elaboration of adverse effects is unknown for many polyphenols. Moreover, a considerable amount of evidence is accumulating which supports the hypothesis that high-dose polyphenols can mechanistically cause adverse effects through pro-oxidative action. Thus, polyphenol-rich dietary supplements can potentially confer additional benefits but high-doses may elicit toxicity thereby establishing a double-edge sword in supplement use.Keywords: antioxidant, bioavailability, flavonoids, polyphenols, supplement

  17. Curcumin Mitigates the Intracellular Lipid Deposit Induced by Antipsychotics In Vitro.

    Directory of Open Access Journals (Sweden)

    Alberto Canfrán-Duque

    Full Text Available First- and second-generation antipsychotics (FGAs and SGAs, respectively, both inhibit cholesterol biosynthesis and impair the intracellular cholesterol trafficking, leading to lipid accumulation in the late endosome/lysosome compartment. In this study we examined if curcumin, a plant polyphenol that stimulates exosome release, can alleviate antipsychotic-induced intracellular lipid accumulation.HepG2 hepatocarcinoma cells were treated with antipsychotics or placebo and DiI-labelled LDL for 18 h and then exposed to curcumin for the last 2 h. Cells and media were collected separately and used for biochemical analyses, electron microscopy and immunocytochemistry. Exosomes were isolated from the incubation medium by ultracentrifugation.Curcumin treatment reduced the number of heterolysosomes and shifted their subcellular localization to the periphery, as revealed by electron microscopy, and stimulated the release of lysosomal β-hexosaminidase and exosome markers flotillin-2 and CD63 into the media. The presence of DiI in exosomes released by cells preloaded with DiI-LDL demonstrated the endolysosomal origin of the microvesicles. Furthermore, curcumin increased the secretion of cholesterol as well as LDL-derived DiI and [3H]-cholesterol, in association with a decrease of intracellular lipids. Thus, the disruption of lipid trafficking induced by FGAs or SGAs can be relieved by curcumin treatment. This polyphenol, however, did not mitigate the reduction of cholesterol esterification induced by antipsychotics.Curcumin stimulates exosome release to remove cholesterol (and presumably other lipids accumulated within the endolysosomal compartment, thereby normalizing intracellular lipid homeostasis. This action may help minimize the adverse metabolic effects of antipsychotic treatment, which should now be evaluated in clinical trials.

  18. Cytoprotective Mechanisms Mediated by Polyphenols from Chilean Native Berries against Free Radical-Induced Damage on AGS Cells

    Directory of Open Access Journals (Sweden)

    Felipe Ávila

    2017-01-01

    Full Text Available The prevalence of cytoprotective mechanisms induced by polyphenols such as activation of intracellular antioxidant responses (ICM and direct free radical scavenging was investigated in native Chilean species of strawberries, raspberries, and currants. Human gastric epithelial cells were co- and preincubated with polyphenolic-enriched extracts (PEEs from Chilean raspberries (Rubus geoides, strawberries (Fragaria chiloensis ssp. chiloensis f. chiloensis, and currants (Ribes magellanicum and challenged with peroxyl and hydroxyl radicals. Cellular protection was determined in terms of cell viability, glyoxalase I and glutathione s-transferases activities, and carboxymethyl lysine (CML and malondialdehyde levels. Our results indicate that cytoprotection induced by ICM was the prevalent mechanism for Rubus geoides and F. chiloensis. This agreed with increased levels of glyoxalase I and glutathione S-transferase activities in cells preincubated with PEEs. ORAC index indicated that F. chiloensis was the most efficient peroxyl radical scavenger. Moreover, ICM mediated by F. chiloensis was effective in protecting cells from CML accumulation in contrast to the protective effects induced by free radical scavenging. Our results indicate that although both polyphenol-mediated mechanisms can exert protective effects, ICM was the most prevalent in AGS cells. These results suggest a potential use of these native berries as functional food.

  19. Cytoprotective Mechanisms Mediated by Polyphenols from Chilean Native Berries against Free Radical-Induced Damage on AGS Cells.

    Science.gov (United States)

    Ávila, Felipe; Theoduloz, Cristina; López-Alarcón, Camilo; Dorta, Eva; Schmeda-Hirschmann, Guillermo

    2017-01-01

    The prevalence of cytoprotective mechanisms induced by polyphenols such as activation of intracellular antioxidant responses (ICM) and direct free radical scavenging was investigated in native Chilean species of strawberries, raspberries, and currants. Human gastric epithelial cells were co- and preincubated with polyphenolic-enriched extracts (PEEs) from Chilean raspberries ( Rubus geoides ), strawberries ( Fragaria chiloensis ssp. chiloensis f . chiloensis ), and currants ( Ribes magellanicum ) and challenged with peroxyl and hydroxyl radicals. Cellular protection was determined in terms of cell viability, glyoxalase I and glutathione s-transferases activities, and carboxymethyl lysine (CML) and malondialdehyde levels. Our results indicate that cytoprotection induced by ICM was the prevalent mechanism for Rubus geoides and F. chiloensis . This agreed with increased levels of glyoxalase I and glutathione S-transferase activities in cells preincubated with PEEs. ORAC index indicated that F. chiloensis was the most efficient peroxyl radical scavenger. Moreover, ICM mediated by F. chiloensis was effective in protecting cells from CML accumulation in contrast to the protective effects induced by free radical scavenging. Our results indicate that although both polyphenol-mediated mechanisms can exert protective effects, ICM was the most prevalent in AGS cells. These results suggest a potential use of these native berries as functional food.

  20. Stochastic models of intracellular transport

    KAUST Repository

    Bressloff, Paul C.

    2013-01-09

    The interior of a living cell is a crowded, heterogenuous, fluctuating environment. Hence, a major challenge in modeling intracellular transport is to analyze stochastic processes within complex environments. Broadly speaking, there are two basic mechanisms for intracellular transport: passive diffusion and motor-driven active transport. Diffusive transport can be formulated in terms of the motion of an overdamped Brownian particle. On the other hand, active transport requires chemical energy, usually in the form of adenosine triphosphate hydrolysis, and can be direction specific, allowing biomolecules to be transported long distances; this is particularly important in neurons due to their complex geometry. In this review a wide range of analytical methods and models of intracellular transport is presented. In the case of diffusive transport, narrow escape problems, diffusion to a small target, confined and single-file diffusion, homogenization theory, and fractional diffusion are considered. In the case of active transport, Brownian ratchets, random walk models, exclusion processes, random intermittent search processes, quasi-steady-state reduction methods, and mean-field approximations are considered. Applications include receptor trafficking, axonal transport, membrane diffusion, nuclear transport, protein-DNA interactions, virus trafficking, and the self-organization of subcellular structures. © 2013 American Physical Society.

  1. Polyphenol Concentrate from Kazakhstan Cabernet Sauvignon Collection of Grapes

    Directory of Open Access Journals (Sweden)

    Zarina Shulgau

    2014-12-01

    Full Text Available Introduction. Nowadays, most of the research in the field of gerontology is focused on the effects of the grape polyphenols. In particular, resveratrol has been shown to increase life expectancy of various living organisms, including mammals. Resveratrol also plays an important role in cancer prevention and decreases the risk of developing cardiovascular disease. In our research, we proposed the development of the therapeutic product from Cabernet Sauvignon grapes that would exhibit the beneficial properties of polyphenols. Standard operating procedures were developed in our laboratories to collect alcohol free concentrate of polyphenols from the Kazakhstan Cabernet Sauvignon collection of grapes. The purpose of the study was to investigate the composition, biological safety, and potential therapeutic effects of the polyphenol concentrate.Methods. The total polyphenol amount was determined using the Enology Analyzer Y15 (BioSystems, Spain. HPLC analysis of the polyphenol composition was performed using Agilent 1290 chromatograph. The polyphenol concentrate was analyzed for the microbiological purity and the presence of the toxic elements. The cytoprotective effect of the polyphenol concentrate was studied in experimental models of diabetes, toxic hepatitis, doxorubicin cardiomyopathy, and acute radiation sickness.Results. The total polyphenol amount in one sample was 12,819 mg/l. Polyphenol composition analysis showed presence of the following polyphenols: catechin, epicatechin, gallic acid, quercetin, miricetin, 3-glucosylkaempferol, epicatechin gallate, 3-(3,4-Dihydroxyphenyl-2-propenoic acid, catechin gallate, pitseid, kaempferol, n-hydroxy-cinnamic acid, resveratrol and chlorogenic acid. The concentrate was proven to be biologically safe and acceptable for use as a dietary supplement. The polyphenol concentrate demonstrated high antioxidant activity against ABTS and DPPH radicals in vitro. It also showed the following impacts on the various

  2. Alterations of sirtuins in mitochondrial cytochrome c-oxidase deficiency.

    Directory of Open Access Journals (Sweden)

    Arne Björn Potthast

    Full Text Available Sirtuins are NAD+ dependent deacetylases, which regulate mitochondrial energy metabolism as well as cellular response to stress. The NAD/NADH-system plays a crucial role in oxidative phosphorylation linking sirtuins and the mitochondrial respiratory chain. Furthermore, sirtuins are able to directly deacetylate and activate different complexes of the respiratory chain. This prompted us to analyse sirtuin levels in skin fibroblasts from patients with cytochrome c-oxidase (COX deficiency and to test the impact of different pharmaceutical activators of sirtuins (SRT1720, paeonol to modulate sirtuins and possibly respiratory chain enzymes in patient cells in vitro.We assayed intracellular levels of sirtuin 1 and the mitochondrial sirtuins SIRT3 and SIRT4 in human fibroblasts from patients with COX- deficiency. Furthermore, sirtuins were measured after inhibiting complex IV in healthy control fibroblasts by cyanide and after incubation with activators SRT1720 and paeonol. To determine the effect of sirtuin inhibition at the cellular level we measured total cellular acetylation (control and patient cells, with and without treatment by Western blot.We observed a significant decrease in cellular levels of all three sirtuins at the activity, protein and transcriptional level (by 15% to 50% in COX-deficient cells. Additionally, the intracellular concentration of NAD+ was reduced in patient cells. We mimicked the biochemical phenotype of COX- deficiency by incubating healthy fibroblasts with cyanide and observed reduced sirtuin levels. A pharmacological activation of sirtuins resulted in normalized sirtuin levels in patient cells. Hyper acetylation was also reversible after treatment with sirtuin activators. Pharmacological modulation of sirtuins resulted in altered respiratory chain complex activities.We found inhibition of situins 1, 3 and 4 at activity, protein and transcriptional levels in fibroblasts from patient with COX-deficiency. Pharmacological

  3. Biochemical degradation and physical migration of polyphenolic compounds in osmotic dehydrated blueberries with pulsed electric field and thermal pretreatments.

    Science.gov (United States)

    Yu, Yuanshan; Jin, Tony Z; Fan, Xuetong; Wu, Jijun

    2018-01-15

    Fresh blueberries were pretreated by pulsed electric fields (PEF) or thermal pretreatment and then were subject to osmotic dehydration. The changes in contents of anthocyanins, predominantly phenolic acids and flavonols, total phenolics, polyphenol oxidase (PPO) activity and antioxidant activity in the blueberry samples during pretreatment and osmotic dehydration were investigated. Biochemical degradation and physical migration of these nutritive compounds from fruits to osmotic solutions were observed during the pretreatments and osmotic dehydration. PEF pretreated samples had the least degradation loss but the most migration loss of these compounds compared to thermally pretreated and control samples. Higher rates of water loss and solid gain during osmotic dehydration were also obtained by PEF pretreatment, reducing the dehydration time from 130 to 48h. PEF pretreated and dehydrated fruits showed superior appearance to thermally pretreated and control samples. Therefore, PEF pretreatment is a preferred technology that balances nutritive quality, appearance, and dehydration rate. Published by Elsevier Ltd.

  4. Guava leaves polyphenolics-rich extract inhibits vital enzymes implicated in gout and hypertension in vitro

    Science.gov (United States)

    Irondi, Emmanuel Anyachukwu; Agboola, Samson Olalekan; Oboh, Ganiyu; Boligon, Aline Augusti; Athayde, Margareth Linde; Shode, Francis O.

    2016-01-01

    Background/Aim: Elevated uric acid level, an index of gout resulting from the over-activity of xanthine oxidase (XO), increases the risk of developing hypertension. However, research has shown that plant-derived inhibitors of XO and angiotensin 1-converting enzyme (ACE), two enzymes implicated in gout and hypertension, respectively, can prevent or ameliorate both diseases, without noticeable side effects. Hence, this study characterized the polyphenolics composition of guava leaves extract and evaluated its inhibitory effect on XO and ACE in vitro. Materials and Methods: The polyphenolics (flavonoids and phenolic acids) were characterized using high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD). The XO, ACE, and Fe2+-induced lipid peroxidation inhibitory activities, and free radicals (2,2-diphenylpicrylhydrazyl [DPPH]* and 2,2´-azino-bis-3-ethylbenzthiazoline-6-sulphonic [ABTS]*+) scavenging activities of the extract were determined using spectrophotometric methods. Results: Flavonoids were present in the extract in the order of quercetin > kaempferol > catechin > quercitrin > rutin > luteolin > epicatechin; while phenolic acids were in the order of caffeic acid > chlorogenic acid > gallic acids. The extract effectively inhibited XO, ACE and Fe2+-induced lipid peroxidation in a dose-dependent manner; having half-maximal inhibitory concentrations (IC50) of 38.24 ± 2.32 μg/mL, 21.06 ± 2.04 μg/mL and 27.52 ± 1.72 μg/mL against XO, ACE and Fe2+-induced lipid peroxidation, respectively. The extract also strongly scavenged DPPH* and ABTS*+. Conclusion: Guava leaves extract could serve as functional food for managing gout and hypertension and attenuating the oxidative stress associated with both diseases. PMID:27104032

  5. Guava leaves polyphenolics-rich extract inhibits vital enzymes implicated in gout and hypertension in vitro.

    Science.gov (United States)

    Irondi, Emmanuel Anyachukwu; Agboola, Samson Olalekan; Oboh, Ganiyu; Boligon, Aline Augusti; Athayde, Margareth Linde; Shode, Francis O

    2016-01-01

    Elevated uric acid level, an index of gout resulting from the over-activity of xanthine oxidase (XO), increases the risk of developing hypertension. However, research has shown that plant-derived inhibitors of XO and angiotensin 1-converting enzyme (ACE), two enzymes implicated in gout and hypertension, respectively, can prevent or ameliorate both diseases, without noticeable side effects. Hence, this study characterized the polyphenolics composition of guava leaves extract and evaluated its inhibitory effect on XO and ACE in vitro. The polyphenolics (flavonoids and phenolic acids) were characterized using high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD). The XO, ACE, and Fe(2+)-induced lipid peroxidation inhibitory activities, and free radicals (2,2-diphenylpicrylhydrazyl [DPPH]* and 2,2´-azino-bis-3-ethylbenzthiazoline-6-sulphonic [ABTS]*(+)) scavenging activities of the extract were determined using spectrophotometric methods. Flavonoids were present in the extract in the order of quercetin > kaempferol > catechin > quercitrin > rutin > luteolin > epicatechin; while phenolic acids were in the order of caffeic acid > chlorogenic acid > gallic acids. The extract effectively inhibited XO, ACE and Fe(2+)-induced lipid peroxidation in a dose-dependent manner; having half-maximal inhibitory concentrations (IC50) of 38.24 ± 2.32 μg/mL, 21.06 ± 2.04 μg/mL and 27.52 ± 1.72 μg/mL against XO, ACE and Fe(2+)-induced lipid peroxidation, respectively. The extract also strongly scavenged DPPH* and ABTS*(+). Guava leaves extract could serve as functional food for managing gout and hypertension and attenuating the oxidative stress associated with both diseases.

  6. Characterization of Leptin Intracellular Trafficking

    Directory of Open Access Journals (Sweden)

    E Walum

    2009-12-01

    Full Text Available Leptin is produced by adipose tissue, and its concentration in plasma is related to the amount of fat in the body. The leptin receptor (OBR is a member of the class I cytokine receptor family and several different isoforms, produced by alternative mRNA splicing are found in many tissues, including the hypothalamus. The two predominant isoforms includes a long form (OBRl with an intracellular domain of 303 amino acids and a shorter form (OBRs with an intracellular domain of 34 amino acids. Since OBRl is mainly expressed in the hypotalamus, it has been suggested to be the main signalling form. The peripheral production of leptin by adipocyte tissue and its effects as a signal of satiety in the central nervous system imply that leptin gains access to regions of the brain regulating in energy balance by crossing the blood-brain barrier. In an attempt to characterize the intracellular transport of leptin, we have followed binding internalization and degradation of leptin in HEK293 cells. We have also monitored the intracellular transport pathway of fluorescent conjugated leptin in HEK293 cells. Phenylarsine oxide, a general inhibitor of endocytosis, as well as incubation at mild hypertonic conditions, prevented the uptake of leptin, confirming a receptor-mediated internalization process. When internalized, 125I-leptin was rapidly accumulated inside the cells and reached a maximum after 10 min. After 70 minutes about 40-50% of total counts in each time point were found in the medium as TCA-soluble material. Leptin sorting, at the level of early endosomes, did not seem to involve recycling endosomes, since FITC-leptin was sorted from Cy3- transferrin containing compartments at 37°C. At 45 minutes of continuos internalization, FITC-leptin appeared mainly accumulated in late endocytic structures colocalizing with internalized rhodamine coupled epidermial growth factor (EGF and the lysosomal marker protein lamp-1. The transport of leptin was also shown

  7. Polyphenols as Modulators of Aquaporin Family in Health and Disease.

    Science.gov (United States)

    Fiorentini, Diana; Zambonin, Laura; Dalla Sega, Francesco Vieceli; Hrelia, Silvana

    2015-01-01

    Polyphenols are bioactive molecules widely distributed in fruits, vegetables, cereals, and beverages. Polyphenols in food sources are extensively studied for their role in the maintenance of human health and in the protection against development of chronic/degenerative diseases. Polyphenols act mainly as antioxidant molecules, protecting cell constituents against oxidative damage. The enormous number of polyphenolic compounds leads to huge different mechanisms of action not fully understood. Recently, some evidence is emerging about the role of polyphenols, such as curcumin, pinocembrin, resveratrol, and quercetin, in modulating the activity of some aquaporin (AQP) isoforms. AQPs are integral, small hydrophobic water channel proteins, extensively expressed in many organs and tissues, whose major function is to facilitate the transport of water or glycerol over cell plasma membranes. Here we summarize AQP physiological functions and report emerging evidence on the implication of these proteins in a number of pathophysiological processes. In particular, this review offers an overview about the role of AQPs in brain, eye, skin diseases, and metabolic syndrome, focusing on the ability of polyphenols to modulate AQP expression. This original analysis can contribute to elucidating some peculiar effects exerted by polyphenols and can lead to the development of an innovative potential preventive/therapeutic strategy.

  8. Polyphenols as Modulators of Aquaporin Family in Health and Disease

    Directory of Open Access Journals (Sweden)

    Diana Fiorentini

    2015-01-01

    Full Text Available Polyphenols are bioactive molecules widely distributed in fruits, vegetables, cereals, and beverages. Polyphenols in food sources are extensively studied for their role in the maintenance of human health and in the protection against development of chronic/degenerative diseases. Polyphenols act mainly as antioxidant molecules, protecting cell constituents against oxidative damage. The enormous number of polyphenolic compounds leads to huge different mechanisms of action not fully understood. Recently, some evidence is emerging about the role of polyphenols, such as curcumin, pinocembrin, resveratrol, and quercetin, in modulating the activity of some aquaporin (AQP isoforms. AQPs are integral, small hydrophobic water channel proteins, extensively expressed in many organs and tissues, whose major function is to facilitate the transport of water or glycerol over cell plasma membranes. Here we summarize AQP physiological functions and report emerging evidence on the implication of these proteins in a number of pathophysiological processes. In particular, this review offers an overview about the role of AQPs in brain, eye, skin diseases, and metabolic syndrome, focusing on the ability of polyphenols to modulate AQP expression. This original analysis can contribute to elucidating some peculiar effects exerted by polyphenols and can lead to the development of an innovative potential preventive/therapeutic strategy.

  9. Polyphenols: Extraction Methods, Antioxidative Action, Bioavailability and Anticarcinogenic Effects

    Directory of Open Access Journals (Sweden)

    Eva Brglez Mojzer

    2016-07-01

    Full Text Available Being secondary plant metabolites, polyphenols represent a large and diverse group of substances abundantly present in a majority of fruits, herbs and vegetables. The current contribution is focused on their bioavailability, antioxidative and anticarcinogenic properties. An overview of extraction methods is also given, with supercritical fluid extraction highlighted as a promising eco-friendly alternative providing exceptional separation and protection from degradation of unstable polyphenols. The protective role of polyphenols against reactive oxygen and nitrogen species, UV light, plant pathogens, parasites and predators results in several beneficial biological activities giving rise to prophylaxis or possibly even to a cure for several prevailing human diseases, especially various cancer types. Omnipresence, specificity of the response and the absence of or low toxicity are crucial advantages of polyphenols as anticancer agents. The main problem represents their low bioavailability and rapid metabolism. One of the promising solutions lies in nanoformulation of polyphenols that prevents their degradation and thus enables significantly higher concentrations to reach the target cells. Another, more practiced, solution is the use of mixtures of various polyphenols that bring synergistic effects, resulting in lowering of the required therapeutic dose and in multitargeted action. The combination of polyphenols with existing drugs and therapies also shows promising results and significantly reduces their toxicity.

  10. Potential Health Benefits of Olive Oil and Plant Polyphenols.

    Science.gov (United States)

    Gorzynik-Debicka, Monika; Przychodzen, Paulina; Cappello, Francesco; Kuban-Jankowska, Alicja; Marino Gammazza, Antonella; Knap, Narcyz; Wozniak, Michal; Gorska-Ponikowska, Magdalena

    2018-02-28

    Beneficial effects of natural plant polyphenols on the human body have been evaluated in a number of scientific research projects. Bioactive polyphenols are natural compounds of various chemical structures. Their sources are mostly fruits, vegetables, nuts and seeds, roots, bark, leaves of different plants, herbs, whole grain products, processed foods (dark chocolate), as well as tea, coffee, and red wine. Polyphenols are believed to reduce morbidity and/or slow down the development of cardiovascular and neurodegenerative diseases as well as cancer. Biological activity of polyphenols is strongly related to their antioxidant properties. They tend to reduce the pool of reactive oxygen species as well as to neutralize potentially carcinogenic metabolites. A broad spectrum of health-promoting properties of plant polyphenols comprises antioxidant, anti-inflammatory, anti-allergic, anti-atherogenic, anti-thrombotic, and anti-mutagenic effects. Scientific studies present the ability of polyphenols to modulate the human immune system by affecting the proliferation of white blood cells, and also the production of cytokines or other factors that participate in the immunological defense. The aim of the review is to focus on polyphenols of olive oil in context of their biological activities.

  11. Quantum dots as optical labels for ultrasensitive detection of polyphenols.

    Science.gov (United States)

    Akshath, Uchangi Satyaprasad; Shubha, Likitha R; Bhatt, Praveena; Thakur, Munna Singh

    2014-07-15

    Considering the fact that polyphenols have versatile activity in-vivo, its detection and quantification is very much important for a healthy diet. Laccase enzyme can convert polyphenols to yield mono/polyquinones which can quench Quantum dots fluorescence. This phenomenon of charge transfer from quinones to QDs was exploited as optical labels to detect polyphenols. CdTe QD may undergo dipolar interaction with quinones as a result of broad spectral absorption due to multiple excitonic states resulting from quantum confinement effects. Thus, "turn-off" fluorescence method was applied for ultrasensitive detection of polyphenols by using laccase. We observed proportionate quenching of QDs fluorescence with respect to polyphenol concentration in the range of 100 µg to 1 ng/mL. Also, quenching of the photoluminescence was highly efficient and stable and could detect individual and total polyphenols with high sensitivity (LOD-1 ng/mL). Moreover, proposed method was highly efficient than any other reported methods in terms of sensitivity, specificity and selectivity. Therefore, a novel optical sensor was developed for the detection of polyphenols at a sensitive level based on the charge transfer mechanism. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Interactions between CYP3A4 and Dietary Polyphenols

    Directory of Open Access Journals (Sweden)

    Loai Basheer

    2015-01-01

    Full Text Available The human cytochrome P450 enzymes (P450s catalyze oxidative reactions of a broad spectrum of substrates and play a critical role in the metabolism of xenobiotics, such as drugs and dietary compounds. CYP3A4 is known to be the main enzyme involved in the metabolism of drugs and most other xenobiotics. Dietary compounds, of which polyphenolics are the most studied, have been shown to interact with CYP3A4 and alter its expression and activity. Traditionally, the liver was considered the prime site of CYP3A-mediated first-pass metabolic extraction, but in vitro and in vivo studies now suggest that the small intestine can be of equal or even greater importance for the metabolism of polyphenolics and drugs. Recent studies have pointed to the role of gut microbiota in the metabolic fate of polyphenolics in human, suggesting their involvement in the complex interactions between dietary polyphenols and CYP3A4. Last but not least, all the above suggests that coadministration of drugs and foods that are rich in polyphenols is expected to stimulate undesirable clinical consequences. This review focuses on interactions between dietary polyphenols and CYP3A4 as they relate to structural considerations, food-drug interactions, and potential negative consequences of interactions between CYP3A4 and polyphenols.

  13. Evaluation of polyphenol content in different parts of physalis ixocarpa

    International Nuclear Information System (INIS)

    Bakht, J.; Shafi, M.

    2016-01-01

    In the current study extracts of leaf, stem, fruit and calyx with different polarity was investigated for their phenolic content using high performance liquid chromatography and spectrophotometric assay. Among different parts, stem contain high concentration of total polyphenol and gallic acid. The effect of extraction solvent on polyphenol quantification was observed in both assays. Spectrophotometric analysis of the data regarding polyphenol content indicated that among different extracts from the stem, leaf and fruit tissues; ethyl acetate extracted fraction of stem measured maximum polyphenol content of 110.376 mgGAE/g of dry extract. The ethyl acetate extracted sample of leaf showed high polyphenol (Gallic acid) content of 95 mg GAE/g of dry extract using high performance liquid chromatography assay. The amounts of phenolic content (Gallic acid) extracted from the parts of the plant with the different solvent ranged from 0.0354- 95 mg GAE/g of the dry extract using HPLC, however, spectrophotometric assay indicated total polyphenol ranged from 38-110.37 mgGAE g-1 of the dry extract. The current study suggested that ethyl acetate is an effective solvent for the extraction of polyphenol in different parts of P. ixocarapa. (author)

  14. Polyphenols in Food: Cancer Prevention and Apoptosis Induction.

    Science.gov (United States)

    Sharma, Ashita; Kaur, Mandeep; Katnoria, Jatinder Kaur; Nagpal, Avinash Kaur

    2017-10-06

    Polyphenols are group of water-soluble organic compounds, mainly of natural origin. The compounds having about 5-7 aromatic rings and more than 12 phenolic hydroxyl groups are classified as polyphenols. These are the antioxidants which protect the body from oxidative damage. In plants, they are the secondary metabolites produced as a defense mechanism against stress factors. Antioxidant property of polyphenols is suggested to provide protection against many diseases associated with reactive oxygen species (ROS), including cancer. Various studies carried out across the world have suggested that polyphenols can inhibit the tumor generation, induce apoptosis in cancer cells and interfere in progression of tumors. This group of wonder compounds is present in surplus in natural plants and food products. Intake of polyphenols through diet can scavenge ROS and thus can help in cancer prevention. The plant derived products can also be used along with conventional chemotherapy to enhance the chemopreventive effects. The present review focuses on various in vitro and in vivo studies carried out to assess the anti-carcinogenic potential of polyphenols present in our food. Also, the pathways involved in cancer chemopreventive effects of various subclasses (flavonoids, lignans, stilbenes and phenolic acids) of polyphenols are discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Potential Health Benefits of Olive Oil and Plant Polyphenols

    Directory of Open Access Journals (Sweden)

    Monika Gorzynik-Debicka

    2018-02-01

    Full Text Available Beneficial effects of natural plant polyphenols on the human body have been evaluated in a number of scientific research projects. Bioactive polyphenols are natural compounds of various chemical structures. Their sources are mostly fruits, vegetables, nuts and seeds, roots, bark, leaves of different plants, herbs, whole grain products, processed foods (dark chocolate, as well as tea, coffee, and red wine. Polyphenols are believed to reduce morbidity and/or slow down the development of cardiovascular and neurodegenerative diseases as well as cancer. Biological activity of polyphenols is strongly related to their antioxidant properties. They tend to reduce the pool of reactive oxygen species as well as to neutralize potentially carcinogenic metabolites. A broad spectrum of health-promoting properties of plant polyphenols comprises antioxidant, anti-inflammatory, anti-allergic, anti-atherogenic, anti-thrombotic, and anti-mutagenic effects. Scientific studies present the ability of polyphenols to modulate the human immune system by affecting the proliferation of white blood cells, and also the production of cytokines or other factors that participate in the immunological defense. The aim of the review is to focus on polyphenols of olive oil in context of their biological activities.

  16. Reducing Breast Cancer Recurrence: The Role of Dietary Polyphenolics

    Directory of Open Access Journals (Sweden)

    Andrea J. Braakhuis

    2016-09-01

    Full Text Available Evidence from numerous observational and clinical studies suggest that polyphenolic phytochemicals such as phenolic acids in olive oil, flavonols in tea, chocolate and grapes, and isoflavones in soy products reduce the risk of breast cancer. A dietary food pattern naturally rich in polyphenols is the Mediterranean diet and evidence suggests those of Mediterranean descent have a lower breast cancer incidence. Whilst dietary polyphenols have been the subject of breast cancer risk-reduction, this review will focus on the clinical effects of polyphenols on reducing recurrence. Overall, we recommend breast cancer patients consume a diet naturally high in flavonol polyphenols including tea, vegetables (onion, broccoli, and fruit (apples, citrus. At least five servings of vegetables and fruit daily appear protective. Moderate soy protein consumption (5–10 g daily and the Mediterranean dietary pattern show the most promise for breast cancer patients. In this review, we present an overview of clinical trials on supplementary polyphenols of dietary patterns rich in polyphenols on breast cancer recurrence, mechanistic data, and novel delivery systems currently being researched.

  17. Thermal Characterization of Purified Glucose Oxidase from A Newly Isolated Aspergillus Niger UAF-1

    Science.gov (United States)

    Anjum Zia, Muhammad; Khalil-ur-Rahman; K. Saeed, Muhammad; Andaleeb, Fozia; I. Rajoka, Muhammad; A. Sheikh, Munir; A. Khan, Iftikhar; I. Khan, Azeem

    2007-01-01

    An intracellular glucose oxidase was isolated from the mycelium extract of a locally isolated strain of Aspergillus niger UAF-1. The enzyme was purified to a yield of 28.43% and specific activity of 135 U mg−1 through ammonium sulfate precipitation, anion exchange and gel filtration chromatography. The enzyme showed high affinity for D-glucose with a Km value of 2.56 mM. The enzyme exhibited optimum catalytic activity at pH 5.5. Temperature optimum for glucose oxidase, catalyzed D-glucose oxidation was 40°C. The enzyme showed a high thermostability having a half-life 30 min, enthalpy of denaturation 99.66 kJ mol−1 and free energy of denaturation 103.63 kJ mol−1. These characteristics suggest the use of glucose oxidase from Aspergillus niger UAF-1 as an analytical reagent and in the design of biosensors for clinical, biochemical and diagnostic assays. PMID:18193107

  18. Nuclear expression of lysyl oxidase enzyme is an independent prognostic factor in rectal cancer patients

    DEFF Research Database (Denmark)

    Liu, Na; Cox, Thomas R; Cui, Weiyingqi

    2017-01-01

    Emerging evidence has implicated a pivotal role for lysyl oxidase (LOX) in cancer progression and metastasis. Whilst the majority of work has focused on the extracellular matrix cross-linking role of LOX, the exact function of intracellular LOX localisation remains unclear. In this study, we anal...... the nucleus of colon cancer cell lines by confocal microscopy and Western blot. Our results show a powerful link between nuclear LOX expression in tumours and patient survival, and offer a promising prognostic biomarker for rectal cancer patients....... analysed the LOX expression patterns in the nuclei of rectal cancer patient samples and determined the clinical significance of this expression. Nuclear LOX expression was significantly increased in patient lymph node metastases compared to their primary tumours. High nuclear LOX expression in tumours......Emerging evidence has implicated a pivotal role for lysyl oxidase (LOX) in cancer progression and metastasis. Whilst the majority of work has focused on the extracellular matrix cross-linking role of LOX, the exact function of intracellular LOX localisation remains unclear. In this study, we...

  19. The NADPH oxidase inhibitor apocynin (acetovanillone) induces oxidative stress

    International Nuclear Information System (INIS)

    Riganti, Chiara; Costamagna, Costanzo; Bosia, Amalia; Ghigo, Dario

    2006-01-01

    Apocynin (acetovanillone) is often used as a specific inhibitor of NADPH oxidase. In N11 glial cells, apocynin induced, in a dose-dependent way, a significant increase of both malonyldialdehyde level (index of lipid peroxidation) and lactate dehydrogenase release (index of a cytotoxic effect). Apocynin evoked also, in a significant way, an increase of H 2 O 2 concentration and a decrease of the intracellular glutathione/glutathione disulfide ratio, accompanied by augmented efflux of glutathione and glutathione disulfide. Apocynin induced the activation of both pentose phosphate pathway and tricarboxylic acid cycle, which was blocked when the cells were incubated with glutathione together with apocynin. The cell incubation with glutathione prevented also the apocynin-induced increase of malonyldialdehyde generation and lactate dehydrogenase leakage. Apocynin exerted an oxidant effect also in a cell-free system: indeed, in aqueous solution, it evoked a faster oxidation of the thiols glutathione and dithiothreitol, and elicited the generation of reactive oxygen species, mainly superoxide anions. Our results suggest that apocynin per se can induce an oxidative stress and exert a cytotoxic effect in N11 cells and other cell types, and that some effects of apocynin in in vitro and in vivo experimental models should be interpreted with caution

  20. Interactions of polyphenols with carbohydrates, lipids and proteins.

    Science.gov (United States)

    Jakobek, Lidija

    2015-05-15

    Polyphenols are secondary metabolites in plants, investigated intensively because of their potential positive effects on human health. Their bioavailability and mechanism of positive effects have been studied, in vitro and in vivo. Lately, a high number of studies takes into account the interactions of polyphenols with compounds present in foods, like carbohydrates, proteins or lipids, because these food constituents can have significant effects on the activity of phenolic compounds. This paper reviews the interactions between phenolic compounds and lipids, carbohydrates and proteins and their impact on polyphenol activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Consumption of polyphenol plants may slow aging and associated diseases.

    Science.gov (United States)

    Uysal, Utku; Seremet, Sila; Lamping, Jeffrey W; Adams, Jerome M; Liu, Deede Y; Swerdlow, Russell H; Aires, Daniel J

    2013-01-01

    Slowing aging is a widely shared goal. Plant-derived polyphenols, which are found in commonly consumed food plants such as tea, cocoa, blueberry and grape, have been proposed to have many health benefits, including slowing aging. In-vivo studies have demonstrated the lifespan-extending ability of six polyphenol-containing plants. These include five widely consumed foods (tea, blueberry, cocoa, apple, pomegranate) and a flower commonly used as a folk medicine (betony). These and multiple other plant polyphenols have been shown to have beneficial effects on aging-associated changes across a variety of organisms from worm and fly to rodent and human.

  2. Polyphenol Content, Physicochemical Properties, Enzymatic Activity, Anthocyanin Profiles, and Antioxidant Capacity of Cerasus humilis (Bge. Sok. Genotypes

    Directory of Open Access Journals (Sweden)

    Suwen Liu

    2018-01-01

    Full Text Available Seven varieties of Chinese dwarf cherries were evaluated and compared with respect to their weight, diameter, titratable acidity, total soluble solids, color, polyphenol contents, ascorbic acid levels, anthocyanin profiles, enzymatic activity, and antioxidant capacity. The fruits are rich in phenolic content (339.07–770.30 mg/100 g fresh weight. Nine anthocyanins were obtained from fruits after chromatographic separation and their structures analyzed using HPLC-ESI-MS/MS. Cyanidin-3-glucoside was the major anthocyanin with 50.36–78.39% concentration. Three anthocyanins were reported for the first time in these cherries. They exhibit low polyphenol oxidase and peroxidase activities, but their superoxide dismutase activity is high (572.75–800.17 U/g FW. The highest amounts of soluble solid content (15.67 Brix %, total titratable acid (1.90%, ascorbic acid (18.47 mg/100 g FW, and total anthocyanin (152.66 mg/100 g FW were observed. Three methods (DPPH-scavenging ability, oxygen radical absorbance capacity assay, and cellular antioxidant activity assay were employed to evaluate the antioxidant capacity of the phenolic extracts of these cherries. Number 5 has the highest values of ORAC and CAA of 205.68 μmol TE/g DM and 99.67 μmol QE/100 g FW, respectively.

  3. Red wine polyphenols prevent metabolic and cardiovascular alterations associated with obesity in Zucker fatty rats (Fa/Fa.

    Directory of Open Access Journals (Sweden)

    Abdelali Agouni

    Full Text Available BACKGROUND: Obesity is associated with increased risks for development of cardiovascular diseases. Epidemiological studies report an inverse association between dietary flavonoid consumption and mortality from cardiovascular diseases. We studied the potential beneficial effects of dietary supplementation of red wine polyphenol extract, Provinols, on obesity-associated alterations with respect to metabolic disturbances and cardiovascular functions in Zucker fatty (ZF rats. METHODOLOGY/PRINCIPAL FINDINGS: ZF rats or their lean littermates received normal diet or supplemented with Provinols for 8 weeks. Provinols improved glucose metabolism by reducing plasma glucose and fructosamine in ZF rats. Moreover, it reduced circulating triglycerides and total cholesterol as well as LDL-cholesterol in ZF rats. Echocardiography measurements demonstrated that Provinols improved cardiac performance as evidenced by an increase in left ventricular fractional shortening and cardiac output associated with decreased peripheral arterial resistances in ZF rats. Regarding vascular function, Provinols corrected endothelial dysfunction in aortas from ZF rats by improving endothelium-dependent relaxation in response to acetylcholine (Ach. Provinols enhanced NO bioavailability resulting from increased nitric oxide (NO production through enhanced endothelial NO-synthase (eNOS activity and reduced superoxide anion release via decreased expression of NADPH oxidase membrane sub-unit, Nox-1. In small mesenteric arteries, although Provinols did not affect the endothelium-dependent response to Ach; it enhanced the endothelial-derived hyperpolarizing factor component of the response. CONCLUSIONS/SIGNIFICANCE: Use of red wine polyphenols may be a potential mechanism for prevention of cardiovascular and metabolic alterations associated with obesity.

  4. NADPH Oxidase-Mediated ROS Production Determines Insulin's Action on the Retinal Microvasculature.

    Science.gov (United States)

    Kida, Teruyo; Oku, Hidehiro; Horie, Taeko; Matsuo, Junko; Kobayashi, Takatoshi; Fukumoto, Masanori; Ikeda, Tsunehiko

    2015-10-01

    To determine whether insulin induces nitric oxide (NO) formation in retinal microvessels and to examine the effects of high glucose on the formation of NO. Freshly isolated rat retinal microvessels were incubated in normal (5.5 mM) or high (20 mM) glucose with or without insulin (100 nM). The levels of insulin-induced NO and reactive oxygen species (ROS) in the retinal microvessels were determined semiquantitatively using fluorescent probes, 4,5-diaminofluorescein diacetate, and hydroethidine, respectively, and a laser scanning confocal microscope. The insulin-induced changes of NO in rat retinal endothelial cells and pericytes cultured at different glucose concentrations (5.5 and 25 mM) were determined using flow cytometry. Nitric oxide synthase (NOS) protein levels were determined by Western blot analysis; intracellular levels of ROS were determined using fluorescence-activated cell sorting (FACS) analysis of ethidium fluorescence; and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase RNA expression was quantified using real-time PCR. Exposure of microvessels to insulin under normal glucose conditions led to a significant increase in NO levels; however, this increase was significantly suppressed when the microvessels were incubated under high glucose conditions. Intracellular levels of ROS were significantly increased in both retinal microvessels and cultured microvascular cells under high glucose conditions. The expression of NOS and NADPH oxidase were significantly increased in endothelial cells and pericytes under high glucose conditions. The increased formation of NO by insulin and its suppression by high glucose conditions suggests that ROS production mediated by NADPH oxidase is important by insulin's effect on the retinal microvasculature.

  5. fMLP-Induced IL-8 Release Is Dependent on NADPH Oxidase in Human Neutrophils

    Directory of Open Access Journals (Sweden)

    María A. Hidalgo

    2015-01-01

    Full Text Available N-Formyl-methionyl-leucyl-phenylalanine (fMLP and platelet-activating factor (PAF induce similar intracellular signalling profiles; but only fMLP induces interleukin-8 (IL-8 release and nicotinamide adenine dinucleotide phosphate reduced (NADPH oxidase activity in neutrophils. Because the role of ROS on IL-8 release in neutrophils is until now controversial, we assessed if NADPH oxidase is involved in the IL-8 secretions and PI3K/Akt, MAPK, and NF-κB pathways activity induced by fMLP. Neutrophils were obtained from healthy volunteers. IL-8 was measured by ELISA, IL-8 mRNA by qPCR, and ROS production by luminol-amplified chemiluminescence, reduction of ferricytochrome c, and FACS. Intracellular pH changes were detected by spectrofluorescence. ERK1/2, p38 MAPK, and Akt phosphorylation were analysed by immunoblotting and NF-κB was analysed by immunocytochemistry. Hydroxy-3-methoxyaceto-phenone (HMAP, diphenyleneiodonium (DPI, and siRNA Nox2 reduced the ROS and IL-8 release in neutrophils treated with fMLP. HMAP, DPI, and amiloride (a Na+/H+ exchanger inhibitor inhibited the Akt phosphorylation and did not affect the p38 MAPK and ERK1/2 activity. DPI and HMAP reduced NF-κB translocation induced by fMLP. We showed that IL-8 release induced by fMLP is dependent on NADPH oxidase, and ROS could play a redundant role in cell signalling, ultimately activating the PI3K/Akt and NF-κB pathways in neutrophils.

  6. Crystallization of carbohydrate oxidase from Microdochium nivale

    Czech Academy of Sciences Publication Activity Database

    Dušková, Jarmila; Dohnálek, Jan; Skálová, Tereza; Ostergaard, L. H.; Fuglsang, C. C.; Kolenko, Petr; Štěpánková, Andrea; Hašek, Jindřich

    2009-01-01

    Roč. 65, č. 6 (2009), s. 638-640 ISSN 1744-3091 R&D Projects: GA AV ČR IAA500500701; GA ČR GA305/07/1073 Institutional research plan: CEZ:AV0Z40500505 Keywords : carbohydrate oxidase * crystallization * data processing Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.551, year: 2009

  7. Investigation of antihemolytic, xanthine oxidase inhibition ...

    African Journals Online (AJOL)

    Abbreviations: SVEs: Salvia Verbenaca L. aerial part Extracts; CrE: Crud Extract; ChE: Chloroform Extract ; EAE: Ethyl Acetate Extract; AqE : Aqueous Extract ; ROS: Reactive Oxygen Spices; AAPH : 2,2, -Azobis (2-AmidinoPropane) Dihydrochloride ; DPPH: DiPhenyl- Picryl-Hydrazyl; XO: Xanthine Oxidase; Gen: Gentamicin ...

  8. Genetic defects of cytochrome c oxidase assembly

    Czech Academy of Sciences Publication Activity Database

    Pecina, Petr; Houšťková, H.; Hansíková, H.; Zeman, J.; Houštěk, Josef

    2004-01-01

    Roč. 53, Suppl. 1 (2004), s. S213-S223 ISSN 0862-8408 R&D Projects: GA ČR GA303/03/0749 Institutional research plan: CEZ:AV0Z5011922 Keywords : cytochrome c oxidase * mitochondrial disorders Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.140, year: 2004

  9. The antioxidant properties, cytotoxicity and monoamine oxidase ...

    African Journals Online (AJOL)

    Tarchonanthus camphoratus (camphor bush) has been widely used for numerous medicinal purposes. The aim of the present study was to evaluate the antioxidant properties, cytotoxicity and monoamine oxidase inhibition activities of the crude dichloromethane leaf extract of T. camphoratus. The antioxidant activities were ...

  10. Electron Microscopy of Intracellular Protozoa

    Science.gov (United States)

    1988-12-20

    Classification) " ELECTRON MICROSCOPY OF INTRACELLULAR PROTOZOA 12. PERSONAL AUTHOR(S) Aikawa, Masamichi 13a. TYPE OF REPORT I13b. TIME COVERED 114...authors suggest that anti-CS protein antibody is important in reducing the prevalence of malaria with increasing age among persons in such areas and... Hygine 33, 220-226. 0Giudice, G.D., Engers, H.D., Tougne, C., Biro, S.S., Weiss, N., Verdini, A.S., Pessi, A., Degremont, A.A., Freyvogel, T.A., Lambert

  11. Dietary intake of total polyphenol and polyphenol classes and the risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

    DEFF Research Database (Denmark)

    Zamora-Ros, Raul; Cayssials, Valerie; Jenab, Mazda

    2018-01-01

    Polyphenols may play a chemopreventive role in colorectal cancer (CRC); however, epidemiological evidence supporting a role for intake of individual polyphenol classes, other than flavonoids is insufficient. We evaluated the association between dietary intakes of total and individual classes and ...

  12. Haematological and biochemical effects of polyphenolics in animal models.

    Science.gov (United States)

    Gnanamani, Arumugam; Sudha, Munusamy; Deepa, G; Sudha, M; Deivanai, K; Sadulla, S

    2008-07-01

    Polyphenols of natural and synthetic origin are exploited in tanning sector to convert putrescible skin/hide to non-putrescible leather. However, only 30-40% of the inputs have been taken up for processing, the remaining is released as unspent. The existing conventional wastewater treatment systems are inefficient in removing or degrading these unspent polyphenols and thus detrimental to ecosystem. The present study demonstrates the evaluation of impact of both synthetic and natural polyphenols on biochemical and haematological properties of blood and serum in animal models. The results reveal that concentrations of polyphenols play a major role. At higher concentrations, irrespective of their nature, there was a marked change in the lipid profile (81% reduction), followed by insignificant change in glucose levels, RBC and WBC counts and other haematological parameters. At lower concentrations, no significant changes in the above said properties were observed.

  13. Polyphenolic chemistry of tea and coffee: a century of progress.

    Science.gov (United States)

    Wang, Yu; Ho, Chi-Tang

    2009-09-23

    Tea and coffee, the most popular beverages in the world, have been consumed for thousands of years for their alluring flavors and health benefits. Polyphenols, particularly flavonoids and phenolic acids, are of great abundance in tea and coffee and contribute a lot to their flavor and health properties. This paper reviews the polyphenol chemistry of tea and coffee, specifically their stability, and scavenging ability of reactive oxygen species (ROS) and reactive carbonyl species (RCS). During the manufacturing and brewing process, green tea and black tea polyphenols undergo epimerization and oxidation, respectively. Meanwhile, the lactonization and the polymerization of chlorogenic acid are the major causes for the degradation of polyphenols in coffee. Tea catechins, besides having antioxidant properties, have the novel characteristic of trapping reactive carbonyl species. The A ring of the catechins is the binding site for RCS trapping, whereas the B ring is the preferred site for antioxidation.

  14. Antibacterial action of an aqueous grape seed polyphenolic extract

    African Journals Online (AJOL)

    Jane

    2011-07-06

    Jul 6, 2011 ... The potential of a polyphenolic grape seed extract for use as a natural antibacterial agent was ... electrospray ionisation-mass spectrometry; PBS, phosphate .... The antibacterial tests were carried out by disc diffusion method.

  15. Minerals and Total Polyphenolic Content of Some Vegetal Powders

    Directory of Open Access Journals (Sweden)

    Roxana E. TUFEANU

    2017-11-01

    Full Text Available The total polyphenolic content and minerals were determined for chia seeds, Psyllium husks and watermelon rind powder. The minerals content was performed by using the Inductively Coupled Plasma Optical Emissions Spectrometer and Atomic Absorption Spectrometer, technique FIAS-Furnace (for Se. The sample with the highest content of polyphenols was chia (2.69 mg GAE/g s. followed by the watermelon rind powder. Reduced amounts of polyphenols were found in the Psyllium husks. Also, the total polyphenol concentration increased with the increase of the extraction time on the ultrasonic water bath. Minerals analysis indicated that powders obtained from chia seeds and watermelon rind contained large amounts of potassium, calcium, phosphorus and magnesium. The most abundant mineral in the Psyllium husks powder was found potassium, followed by calcium. In conclusion, these powders can be used as ingredients for functional food and food supplements production due to the high nutritional content and bioactive properties.

  16. Polyphenol-Rich Lentils and Their Health Promoting Effects

    Directory of Open Access Journals (Sweden)

    Kumar Ganesan

    2017-11-01

    Full Text Available Lentil (Lens culinaris; Family: Fabaceae is a potential functional dietary ingredient which has polyphenol-rich content. Several studies have demonstrated that the consumption of lentil is immensely connected to the reduction in the incidence of diseases such as diabetes, obesity, cancers and cardiovascular diseases due to its bioactive compounds. There has been increasing scientific interest in the study area of lentils as the functional food due to its high nutritive value, polyphenols, and other bioactive compounds. These polyphenols and the bioactive compounds found in lentil play an important role in the prevention of those degenerative diseases in humans. Besides that, it has health-promoting effects. Based on the in vitro, in-vivo and clinical studies, the present review focuses to provide more information on the nutritional compositions, bioactive compounds including polyphenols and health-promoting effects of lentils. Health-promoting information was gathered and orchestrated at a suitable place in the review.

  17. Pathogenic mechanisms of intracellular bacteria.

    Science.gov (United States)

    Niller, Hans Helmut; Masa, Roland; Venkei, Annamária; Mészáros, Sándor; Minarovits, Janos

    2017-06-01

    We wished to overview recent data on a subset of epigenetic changes elicited by intracellular bacteria in human cells. Reprogramming the gene expression pattern of various host cells may facilitate bacterial growth, survival, and spread. DNA-(cytosine C5)-methyltransferases of Mycoplasma hyorhinis targeting cytosine-phosphate-guanine (CpG) dinucleotides and a Mycobacterium tuberculosis methyltransferase targeting non-CpG sites methylated the host cell DNA and altered the pattern of gene expression. Gene silencing by CpG methylation and histone deacetylation, mediated by cellular enzymes, also occurred in M. tuberculosis-infected macrophages. M. tuberculosis elicited cell type-specific epigenetic changes: it caused increased DNA methylation in macrophages, but induced demethylation, deposition of euchromatic histone marks and activation of immune-related genes in dendritic cells. A secreted transposase of Acinetobacter baumannii silenced a cellular gene, whereas Mycobacterium leprae altered the epigenotype, phenotype, and fate of infected Schwann cells. The 'keystone pathogen' oral bacterium Porphyromonas gingivalis induced local DNA methylation and increased the level of histone acetylation in host cells. These epigenetic changes at the biofilm-gingiva interface may contribute to the development of periodontitis. Epigenetic regulators produced by intracellular bacteria alter the epigenotype and gene expression pattern of host cells and play an important role in pathogenesis.

  18. Enhanced anodic Ru(bpy)32+ electrogenerated chemiluminescence by polyphenols

    International Nuclear Information System (INIS)

    Lei Rong; Xu Xiao; Xu Da; Zhu Gang; Li Na; Liu Huwei; Li Kean

    2008-01-01

    Anodic Ru(bpy) 3 2+ electrogenerated chemiluminescence (ECL) can be enhanced by polyphenols in alkaline solution. Spin trapping-electron spin resonance (ESR) experiments verified that reactive oxygen species (ROS) were generated during the electrolysis of Ru(bpy) 3 2+ in alkaline solution, and oxidation of quercetin enhanced Ru(bpy) 3 2+ ECL at anodic potential by producing additional ROS. This ECL enhancement can be used to analyze real sample and evaluate antioxidant activity of polyphenols

  19. Analytical techniques for the study of polyphenol-protein interactions.

    Science.gov (United States)

    Poklar Ulrih, Nataša

    2017-07-03

    This mini review focuses on advances in biophysical techniques to study polyphenol interactions with proteins. Polyphenols have many beneficial pharmacological properties, as a result of which they have been the subject of intensive studies. The most conventional techniques described here can be divided into three groups: (i) methods used for screening (in-situ methods); (ii) methods used to gain insight into the mechanisms of polyphenol-protein interactions; and (iii) methods used to study protein aggregation and precipitation. All of these methods used to study polyphenol-protein interactions are based on modifications to the physicochemical properties of the polyphenols or proteins after binding/complex formation in solution. To date, numerous review articles have been published in the field of polyphenols. This review will give a brief insight in computational methods and biosensors and cell-based methods, spectroscopic methods including fluorescence emission, UV-vis adsorption, circular dichroism, Fourier transform infrared and mass spectrometry, nuclear magnetic resonance, X-ray diffraction, and light scattering techniques including small-angle X-ray scattering and small-angle neutron scattering, and calorimetric techniques (isothermal titration calorimetry and differential scanning calorimetry), microscopy, the techniques which have been successfully used for polyphenol-protein interactions. At the end the new methods based on single molecule detection with high potential to study polyphenol-protein interactions will be presented. The advantages and disadvantages of each technique will be discussed as well as the thermodynamic, kinetic or structural parameters, which can be obtained. The other relevant biophysical experimental techniques that have proven to be valuable, such electrochemical methods, hydrodynamic techniques and chromatographic techniques will not be described here.

  20. Polyphenol supplementation: benefits for exercise performance or oxidative stress?

    Science.gov (United States)

    Myburgh, Kathryn H

    2014-05-01

    Supplement use among athletes is widespread, including non-traditional and biological compounds. Despite increasing research, a comprehensive and critical review on polyphenol supplementation and exercise is still lacking. This review is relevant for researchers directly involved in the topic, as well as those with a broad interest in athletic performance enhancement and sports nutrition. The purpose of this review is to present background information on groups of polyphenols and their derivatives because their differing chemical structures influence mechanisms of action; to discuss the potential of plant, fruit and vegetable-based biological supplements, high in polyphenol content, to affect exercise performance and biomarkers of oxidative stress and exercise-induced muscle damage; and to critically discuss the exercise studies and biomarkers used. Subjects in the studies reviewed were either sedentary, healthy individuals, or active, recreationally trained or well-trained athletes. Polyphenol supplementation in exercise studies included mainly extracts (multicomponent or purified), juices, infusions or an increased intake of polyphenol-rich foods. This review includes details of supplement doses and exercise test protocols. Many studies considered only the performance or one or two selected biomarkers of antioxidant capacity instead of a comprehensive choice of biomarkers to assess damage to lipids or proteins. Evidence is insufficient to make recommendations for or against the use of polyphenol supplementation (neither specific polyphenols nor specific doses) for either recreational, competitive or elite athletes. Polyphenols have multiple biological effects, and future exercise studies must be designed appropriately and specifically to determine physiological interactions between exercise and the selected supplement, rather than considering performance alone.

  1. A role for NADPH oxidase in antigen presentation

    Directory of Open Access Journals (Sweden)

    Gail J Gardiner

    2013-09-01

    Full Text Available The nicotinamide adenine dinucleotide phosphate (NADPH oxidase expressed in phagocytes is a multi-subunit enzyme complex that generates superoxide (O2.-. This radical is an important precursor of hydrogen peroxide (H2O2 and other reactive oxygen species (ROS needed for microbicidal activity during innate immune responses. Inherited defects in NADPH oxidase give rise to chronic granulomatous disease (CGD, a primary immunodeficiency characterized by recurrent infections and granulomatous inflammation. Interestingly, CGD, CGD carrier status, and oxidase gene polymorphisms have all been associated with autoinflammatory and autoimmune disorders, suggesting a potential role for NADPH oxidase in regulating adaptive immune responses. Here, NADPH oxidase function in antigen processing and presentation is reviewed. NADPH oxidase influences dendritic cell (DC crosspresentation by major histocompatibility complex class I molecules (MHC-I through regulation of the phagosomal microenvironment, while in B lymphocytes, NADPH oxidase alters epitope selection by major histocompatibility complex class II molecules (MHC-II.

  2. Polyphenol profiles of French cider apple varieties (Malus domestica sp.).

    Science.gov (United States)

    Sanoner, P; Guyot, S; Marnet, N; Molle, D; Drilleau, J P

    1999-12-01

    The cortex of 14 French apple varieties (12 cider and 2 juice varieties), one English cider variety, and one dessert apple (i.e., Golden Delicious) were studied for their polyphenol composition. Total polyphenols were assayed by the Folin-Ciocalteu method, and the precise polyphenolic composition (monomeric catechins, proanthocyanidins, hydroxycinnamic acids, and dihydrochalcones) was obtained by HPLC following thiolysis. ESI-MS and ESI-MS/MS analyses showed that chlorogenic acid and p-coumaroylquinic acid were methylated under the conditions of thiolysis. Depending on the variety, the global polyphenol concentration varied from 1 to 7 g per kilogram of fresh cortex. Cider varieties globally showed a higher polyphenol concentration than the dessert apple Golden Delicious, bitter varieties being the more concentrated. The proportion of the polyphenol classes varied greatly from one cultivar to another. For all varieties, procyanidins were always the predominant class. They were mainly constituted of (-)-epicatechin units with a small proportion of (+)-catechin as a terminal unit. The average degree of polymerization ranged between 4.2 and 7.5 depending upon the variety with an exception for the sharp varieties Guillevic and Avrolles which showed significant concentrations of procyanidins with DPn of 40 and 50, respectively.

  3. High nitrogen availability reduces polyphenol content in Sphagnum peat.

    Science.gov (United States)

    Bragazza, Luca; Freeman, Chris

    2007-05-15

    Peat mosses of the genus Sphagnum constitute the bulk of living and dead biomass in bogs. These plants contain peculiar polyphenols which hamper litter peat decomposition through their inhibitory activity on microbial breakdown. In the light of the increasing availability of biologically active nitrogen in natural ecosystems, litter derived from Sphagnum mosses is an ideal substrate to test the potential effects of increased atmospheric nitrogen deposition on polyphenol content in litter peat. To this aim, we measured total nitrogen and soluble polyphenol concentration in Sphagnum litter peat collected in 11 European bogs under a chronic gradient of atmospheric nitrogen deposition. Our results demonstrate that increasing nitrogen concentration in Sphagnum litter, as a consequence of increased exogenous nitrogen availability, is accompanied by a decreasing concentration of polyphenols. This inverse relationship is consistent with reports that in Sphagnum mosses, polyphenol and protein biosynthesis compete for the same precursor. Our observation of modified Sphagnum litter chemistry under chronic nitrogen eutrophication has implications in the context of the global carbon balance, because a lower content of decay-inhibiting polyphenols would accelerate litter peat decomposition.

  4. The Relevance of Dietary Polyphenols in Cardiovascular Protection.

    Science.gov (United States)

    Murillo, Ana G; Fernandez, Maria L

    2017-01-01

    The chemical structure of polyphenols consisting of aromatic rings, capable of quenching free radicals, makes them ideal candidates to protect against oxidation. Polyphenols are present in a variety of foods including grapes, berries, dark chocolate, coffee and tea to mention a few. A number of studies have shown that dietary polyphenols exert a protective effect against hypertension, dyslipidemias, inflammation, endothelial function and atherosclerosis, conditions associated with increased risk for cardiovascular disease. Studies indicate that by decreasing cholesterol absorption, polyphenols alter hepatic cholesterol homeostasis resulting in decreases in plasma lipids and reduction in atherogenic lipoproteins thus having a protective effect against atherosclerosis; polyphenols have also been shown to decrease the activity of enzymes involved in the renin-angiotensinaldosterone system and improve blood pressure. Further, they have been recognized to increase nitric oxide production and to improve endothelial function. In this review we will present some of the evidence derived from epidemiological studies, clinical interventions as well as animal and cell studies supporting the cardioprotective effects of dietary polyphenols. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  5. Polyphenol-Rich Lentils and Their Health Promoting Effects.

    Science.gov (United States)

    Ganesan, Kumar; Xu, Baojun

    2017-11-10

    Polyphenols are a group of plant metabolites with potent antioxidant properties, which protect against various chronic diseases induced by oxidative stress. Evidence showed that dietary polyphenols have emerged as one of the prominent scientific interests due to their role in the prevention of degenerative diseases in humans. Possible health beneficial effects of polyphenols are measured based on the human consumption and their bioavailability. Lentil ( Lens culinaris ; Family: Fabaceae) is a great source of polyphenol compounds with various health-promoting properties. Polyphenol-rich lentils have a potential effect on human health, possessing properties such as antioxidant, antidiabetic, anti-obesity, anti-hyperlipidemic, anti-inflammatory and anticancer. Based on the explorative study, the current comprehensive review aims to give up-to-date information on nutritive compositions, bioactive compounds and the health-promoting effect of polyphenol-rich lentils, which explores their therapeutic values for future clinical studies. All data of in vitro , in vivo and clinical studies of lentils and their impact on human health were collected from a library database and electronic search (Science Direct, PubMed and Google Scholar). Health-promoting information was gathered and orchestrated in the suitable place in the review.

  6. Oxidative Stress Type Influences the Properties of Antioxidants Containing Polyphenols in RINm5F Beta Cells

    Directory of Open Access Journals (Sweden)

    Nathalie Auberval

    2015-01-01

    Full Text Available The in vitro methods currently used to screen bioactive compounds focus on the use of a single model of oxidative stress. However, this simplistic view may lead to conflicting results. The aim of this study was to evaluate the antioxidant properties of two natural extracts (a mix of red wine polyphenols (RWPs and epigallocatechin gallate (EGCG with three models of oxidative stress induced with hydrogen peroxide (H2O2, a mixture of hypoxanthine and xanthine oxidase (HX/XO, or streptozotocin (STZ in RINm5F beta cells. We employed multiple approaches to validate their potential as therapeutic treatment options, including cell viability, reactive oxygen species production, and antioxidant enzymes expression. All three oxidative stresses induced a decrease in cell viability and an increase in apoptosis, whereas the level of ROS production was variable depending on the type of stress. The highest level of ROS was found for the HX/XO-induced stress, an increase that was reflected by higher expression antioxidant enzymes. Further, both antioxidant compounds presented beneficial effects during oxidative stress, but EGCG appeared to be a more efficient antioxidant. These data indicate that the efficiency of natural antioxidants is dependent on both the nature of the compound and the type of oxidative stress generated.

  7. Relationship between browning and the activities of polyphenol oxidase and phenylalanine ammonia lyase in banana peel during low temperature storage

    NARCIS (Netherlands)

    Nguyen, T.B.T.; Ketsa, S.; Doorn, van W.G.

    2003-01-01

    Kluai Khai (Musa AA Group) and Kluai Hom Thong (Musa AAA Group) bananas were stored at 6 and 10 °C. Visible chilling injury (CI) in the peel, mainly browning, occurred at both temperatures, but more so at 6 °C, and without significant differences between the cultivars. At the time of harvest, total

  8. KARAKTERISASI ENZIM POLIFENOL OKSIDASE BIJI KAKAO (Theobroma cacao Linn. Characterization of Polyphenol Oxidase Enzyme of Cocoa Beans (Theobroma cacao Linn.

    Directory of Open Access Journals (Sweden)

    G.P. Ganda Putra

    2012-05-01

    max equals to 595,24 U/gram (db of cocoa beans and K equals to 0,20 M; result of SDS- PAGE of enzyme shows protein bands at M� of 11,75; 17,80; 27,80; 36,03 and 131,52 kDa; and finally, optimumcondition of enzyme activity is at the temperature of 53,43oC; pH 5,42 and incubation time of 80,91 minutes. ABSTRAK Telah dilakukan penelitian dengan tujuan untuk: (1 mengetahui karakteristik enzim polifenol oksidase dan (2 menen- tukan kondisi (suhu, pH dan waktu inkubasi optimum aktivitas enzim polifenol oksidase, yang diisolasi dari biji kakao kering. Hasil penelitian berupa kondisi (suhu, pH dan waktu inkubasi optimum aktivitas enzim polifenol oksidase akan diaplikasikan untuk perbaikan mutu biji kakao kering melalui teknik rehidrasi. Penelitian ini dilakukan melalui tahapan: (1 isolasi enzim polifenol oksidase dari 10 sampel biji kakao kering di Provinsi Bali, (2 karakterisasi enzim polifenol oksidase (aktivitas, kinetika enzim, BM dan (3 penentuan kondisi suhu, pH dan waktu inkubasi optimum. Hasil yang diperoleh menunjukkan bahwa: (1 aktivitas enzim polifenol oksidase rata-rata 157,49 ± 58,03 U/gram (bk biji kakao dengan aktivitas maksimum 258,22 U/gram (bk biji kakao dan minimum 59,01 U/gram (bk biji kakao; maks sebesar 595,24 U/gram (bk biji kakao dan K sebesar 0,20 M; hasil SDS-PAGE enzim menunjukkan pita-pita protein yang terbentuk pada BM 11,75; 17,80; 27,80; 36,03 dan 131,52 kDa; dan (2 kondisi optimum aktivitas enzimadalah suhu 53,43oC; pH 5,42 dan waktu inkubasi 80,91 menit.

  9. Polyphenol oxidases in Physcomitrella: functional PPO1 knockout modulates cytokinin-dependent developmentin the moss Physcomitrella patens

    Czech Academy of Sciences Publication Activity Database

    Richter, H.; Lieberei, R.; Strnad, Miroslav; Novák, Ondřej; Grúz, Jiří; Rensing, S. A.; von Schwartzenberg, K.

    2012-01-01

    Roč. 63, č. 14 (2012), s. 5121-5135 ISSN 0022-0957 Grant - others:GA MŠk(CZ) ED0007/01/01 Program:ED Institutional research plan: CEZ:AV0Z50380511 Keywords : Cytokinins * gene family * gene replacement Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.242, year: 2012

  10. Lansoprazole induces apoptosis of breast cancer cells through inhibition of intracellular proton extrusion

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Shangrong; Wang, Yifan; Li, Shu Jie, E-mail: shujieli@nankai.edu.cn

    2014-06-13

    Highlights: • Lansoprazole (LPZ) induces cell apoptosis in breast cancer cells. • LPZ markedly inhibits intracellular proton extrusion. • LPZ induces an increase in intracellular ATP level, lysosomal alkalinization and ROS accumulation. - Abstract: The increased glycolysis and proton secretion in tumors is proposed to contribute to the proliferation and invasion of cancer cells during the process of tumorigenesis and metastasis. Here, treatment of human breast cancer cells with proton pump inhibitor (PPI) lansoprazole (LPZ) induces cell apoptosis in a dose-dependent manner. In the implantation of the MDA-MB-231 xenografts in nude mice, administration of LPZ significantly inhibits tumorigenesis and induces large-scale apopotosis of tumor cells. LPZ markedly inhibits intracellular proton extrusion, induces an increase in intracellular ATP level, lysosomal alkalinization and accumulation of reactive oxygen species (ROS) in breast cancer cells. The ROS scavenger N-acetyl-L-cysteine (NAC) and diphenyleneiodonium (DPI), a specific pharmacological inhibitor of NADPH oxidases (NOX), significantly abolish LPZ-induced ROS accumulation in breast cancer cells. Our results suggested that LPZ may be used as a new therapeutic drug for breast tumor.

  11. Lansoprazole induces apoptosis of breast cancer cells through inhibition of intracellular proton extrusion

    International Nuclear Information System (INIS)

    Zhang, Shangrong; Wang, Yifan; Li, Shu Jie

    2014-01-01

    Highlights: • Lansoprazole (LPZ) induces cell apoptosis in breast cancer cells. • LPZ markedly inhibits intracellular proton extrusion. • LPZ induces an increase in intracellular ATP level, lysosomal alkalinization and ROS accumulation. - Abstract: The increased glycolysis and proton secretion in tumors is proposed to contribute to the proliferation and invasion of cancer cells during the process of tumorigenesis and metastasis. Here, treatment of human breast cancer cells with proton pump inhibitor (PPI) lansoprazole (LPZ) induces cell apoptosis in a dose-dependent manner. In the implantation of the MDA-MB-231 xenografts in nude mice, administration of LPZ significantly inhibits tumorigenesis and induces large-scale apopotosis of tumor cells. LPZ markedly inhibits intracellular proton extrusion, induces an increase in intracellular ATP level, lysosomal alkalinization and accumulation of reactive oxygen species (ROS) in breast cancer cells. The ROS scavenger N-acetyl-L-cysteine (NAC) and diphenyleneiodonium (DPI), a specific pharmacological inhibitor of NADPH oxidases (NOX), significantly abolish LPZ-induced ROS accumulation in breast cancer cells. Our results suggested that LPZ may be used as a new therapeutic drug for breast tumor

  12. Role of pH in oxidase variability of Aeromonas hydrophila.

    OpenAIRE

    Hunt, L K; Overman, T L; Otero, R B

    1981-01-01

    Some strains of Aeromonas hydrophila may be oxidase negative or only weakly oxidase positive by the Kovacs method taken from the surface of a differential medium, such as MacConkey agar. Six strains of A. hydrophila, two oxidase variable, one oxidase constant, and three weakly oxidase positive on MacConkey agar, were studied to determine the cause of oxidase variability. The bacteriostatic dyes in MacConkey agar were considered possible inhibitors of the oxidase reaction. The concentration of...

  13. Plasma diamine oxidase activity in asthmatic children

    Directory of Open Access Journals (Sweden)

    Kyoichiro Toyoshima

    1996-01-01

    Full Text Available Histamine plays an important role in the development of asthmatic symptoms. Diamine oxidase (DAO histaminase, which inactivates histamine, is located in the intestine and kidney and is released into plasma. Plasma DAO activity in asthmatic children was measured by a recently developed high performance liquid chromatographic method using histamine as the DAO substrate. Diamine oxidase activity was higher in severely asthmatic children than in those with mild asthma. A time course study during the acute exacerbation phase revealed that DAO activity rose during acute asthmatic attacks and then decreased gradually over several days. Although the mechanisms of plasma DAO activity increase during acute asthmatic attacks could not be explained, data showed that plasma DAO activity is an important index of histamine metabolism in asthmatics and may relate to some mechanisms of acute exacerbation of airway inflammation. Consequently, fluctuations in plasma DAO can be used as one of various indices of instability in management of asthma.

  14. Lysyl Oxidase and the Tumor Microenvironment

    Directory of Open Access Journals (Sweden)

    Tong-Hong Wang

    2016-12-01

    Full Text Available The lysyl oxidase (LOX family of oxidases contains a group of extracellular copper-dependent enzymes that catalyze the cross-linking of collagen and elastin by oxidation, thus maintaining the rigidity and structural stability of the extracellular matrix (ECM. Aberrant expression or activation of LOX alters the cellular microenvironment, leading to many diseases, including atherosclerosis, tissue fibrosis, and cancer. Recently, a number of studies have shown that LOX is overexpressed in most cancers and that it is involved in the regulation of tumor progression and metastasis. In contrast, a few reports have also indicated the tumor-suppressing role of LOX. In this short review, we discuss recent research on the correlations between LOX and cancer. Further, the role of LOX in tumor microenvironment remodeling, tumorigenesis, and metastasis and the underlying mechanisms have also been elucidated.

  15. MR imaging of intracellular and extracellular deoxyhemoglobin

    International Nuclear Information System (INIS)

    Janick, P.A.; Grossman, R.I.; Asakura, T.

    1989-01-01

    MR imaging was performed on varying concentrations of intracellular and extracellular deoxyhemoglobin as well as varying proportions of deoxyhemoglobin and oxyhemoglobin in vitro at 1.5T with use of standard spin-echo and gradient-refocused spin sequences. This study indicates that susceptibility-induced T2 shortening occurs over a broad range of intracellular deoxyhemoglobin concentrations (maximal at hematocrits between 20% and 45%), reflecting diffusional effects at the cellular level. T2* gradient-echo imaging enhances the observed hypointensity in images of intracellular deoxyhemoglobin. The characteristic MR appearance of acute hemotomas can be modeled by the behavior of intracellular and extracellular deoxyhemoglobin and oxyhemoglobin

  16. Monoamine oxidase inhibitors from Gentiana lutea.

    Science.gov (United States)

    Haraguchi, Hiroyuki; Tanaka, Yasumasa; Kabbash, Amal; Fujioka, Toshihiro; Ishizu, Takashi; Yagi, Akira

    2004-08-01

    Three monoamine oxidase (MAO) inhibitors were isolated from Gentiana lutea. Their structures were elucidated to be 3-3''linked-(2'-hydroxy-4-O-isoprenylchalcone)-(2'''-hydroxy-4''-O-isoprenyldihydrochalcone) (1), 2-methoxy-3-(1,1'-dimethylallyl)-6a,10a-dihydrobenzo(1,2-c)chroman-6-one and 5-hydroxyflavanone. These compounds, and the hydrolysis product of 1, displayed competitive inhibitory properties against MAO-B which was more effective than MAO-A.

  17. Imaging Monoamine Oxidase in the Human Brain

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, J. S.; Volkow, N. D.; Wang, G-J.; Logan, Jean

    1999-11-10

    Positron emission tomography (PET) studies mapping monoamine oxidase in the human brain have been used to measure the turnover rate for MAO B; to determine the minimum effective dose of a new MAO inhibitor drug lazabemide and to document MAO inhibition by cigarette smoke. These studies illustrate the power of PET and radiotracer chemistry to measure normal biochemical processes and to provide information on the effect of drug exposure on specific molecular targets.

  18. Imaging Monoamine Oxidase in the Human Brain

    International Nuclear Information System (INIS)

    Fowler, J. S.; Volkow, N. D.; Wang, G-J.; Logan, Jean

    1999-01-01

    Positron emission tomography (PET) studies mapping monoamine oxidase in the human brain have been used to measure the turnover rate for MAO B; to determine the minimum effective dose of a new MAO inhibitor drug lazabemide and to document MAO inhibition by cigarette smoke. These studies illustrate the power of PET and radiotracer chemistry to measure normal biochemical processes and to provide information on the effect of drug exposure on specific molecular targets

  19. Identification of aldehyde oxidase 1 and aldehyde oxidase homologue 1 as dioxin-inducible genes

    International Nuclear Information System (INIS)

    Rivera, Steven P.; Choi, Hyun Ho; Chapman, Brett; Whitekus, Michael J.; Terao, Mineko; Garattini, Enrico; Hankinson, Oliver

    2005-01-01

    Aldehyde oxidases are a family of highly related molybdo-flavoenzymes acting upon a variety of compounds of industrial and medical importance. We have identified aldehyde oxidase 1 (AOX1) as a 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) inducible gene in the mouse hepatoma cell line Hepa-1. AOX1 mRNA levels were not increased by dioxin in mutant derivatives of the Hepa-1 cell line lacking either functional aryl hydrocarbon receptor (AHR) or aryl hydrocarbon receptor nuclear translocator (ARNT) proteins, thus demonstrating that transcriptional induction of AOX1 in response to dioxin occurs through the AHR pathway. Dioxin induction of AOX1 mRNA was also observed in mouse liver. In addition, levels of AOX1 protein as well as those of aldehyde oxidase homologue 1 (AOH1), a recently identified homolog of AOX1, were elevated in mouse liver in response to dioxin. Employing an aldehyde oxidase specific substrate, AOX1/AOH1 activity was shown to be induced by dioxin in mouse liver. This activity was inhibited by a known inhibitor of aldehyde oxidases, and eliminated by including tungstate in the mouse diet, which is known to lead to inactivation of molybdoflavoenzymes, thus confirming that the enzymatic activity was attributable to AOX1/AOH1. Our observations thus identify two additional xenobiotic metabolizing enzymes induced by dioxin

  20. State of polyphenols in the drying process of fruits and vegetables.

    Science.gov (United States)

    McSweeney, M; Seetharaman, K

    2015-01-01

    This review presents an overview of drying technologies and its impact on the polyphenol content of vegetables and fruits. Polyphenols contribute to many health benefits and can act as antioxidants. Specifically an increased intake of polyphenols has been shown to decrease the incidence of cardiovascular disease; furthermore, it has been shown to help reduce the risk of neurodegenerative diseases in humans. Many researchers have reported on the effect of different drying techniques on the polyphenol content in fruits and vegetables. Polyphenol degradation mechanisms proposed in literature and pretreatments that potentially lead to higher retention of polyphenols during drying are also discussed.

  1. Identification of Urinary Polyphenol Metabolite Patterns Associated with Polyphenol-Rich Food Intake in Adults from Four European Countries

    Directory of Open Access Journals (Sweden)

    Hwayoung Noh

    2017-07-01

    Full Text Available We identified urinary polyphenol metabolite patterns by a novel algorithm that combines dimension reduction and variable selection methods to explain polyphenol-rich food intake, and compared their respective performance with that of single biomarkers in the European Prospective Investigation into Cancer and Nutrition (EPIC study. The study included 475 adults from four European countries (Germany, France, Italy, and Greece. Dietary intakes were assessed with 24-h dietary recalls (24-HDR and dietary questionnaires (DQ. Thirty-four polyphenols were measured by ultra-performance liquid chromatography–electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS-MS in 24-h urine. Reduced rank regression-based variable importance in projection (RRR-VIP and least absolute shrinkage and selection operator (LASSO methods were used to select polyphenol metabolites. Reduced rank regression (RRR was then used to identify patterns in these metabolites, maximizing the explained variability in intake of pre-selected polyphenol-rich foods. The performance of RRR models was evaluated using internal cross-validation to control for over-optimistic findings from over-fitting. High performance was observed for explaining recent intake (24-HDR of red wine (r = 0.65; AUC = 89.1%, coffee (r = 0.51; AUC = 89.1%, and olives (r = 0.35; AUC = 82.2%. These metabolite patterns performed better or equally well compared to single polyphenol biomarkers. Neither metabolite patterns nor single biomarkers performed well in explaining habitual intake (as reported in the DQ of polyphenol-rich foods. This proposed strategy of biomarker pattern identification has the potential of expanding the currently still limited list of available dietary intake biomarkers.

  2. Green Tea and Other Tea Polyphenols: Effects on Sebum Production and Acne Vulgaris

    Directory of Open Access Journals (Sweden)

    Suzana Saric

    2016-12-01

    Full Text Available Polyphenols are antioxidant molecules found in many foods including nuts, fruits, vegetables, chocolate, wine, and tea. Polyphenols have antimicrobial, anti-inflammatory, and antineoplastic properties. Recent studies suggest that tea polyphenols may be used for reducing sebum production in the skin and for treatment of acne vulgaris. This review examines the evidence for use of topically and orally ingested tea polyphenols against sebum production and for acne treatment and prevention. The PubMed database was searched for studies on tea polyphenols, sebum secretion, and acne vulgaris. Of the 59 studies found, eight met the inclusion criteria. Two studies evaluated tea polyphenol effects on sebum production; six studies examined tea polyphenol effects on acne vulgaris. Seven studies evaluated topical tea polyphenols; one study examined systemic tea polyphenols. None of the studies evaluated both topical and systemic tea polyphenols. Tea polyphenol sources included green tea (six studies and tea, type not specified (two studies. Overall, there is some evidence that tea polyphenols in topical formulation may be beneficial in reducing sebum secretion and in treatment of acne. Research studies of high quality and with large sample sizes are needed to assess the efficacy of tea polyphenols in topical and oral prevention of acne vulgaris and lipid synthesis by the sebaceous glands.

  3. Modulation of NADPH oxidase activity by known uraemic retention solutes

    DEFF Research Database (Denmark)

    Schulz, Anna Marta; Terne, Cindy; Jankowski, Vera

    2014-01-01

    chloride (DPI), an inhibitor of NADPH oxidase. The effect on enzymatic activity of NADPH oxidase was quantified within an incubation time of 120 min. RESULTS: Thirty-nine of the 48 uraemic retention solutes tested had a significant decreasing effect on NADPH oxidase activity. Oxalate has been characterized......BACKGROUND: Uraemia and cardiovascular disease appear to be associated with an increased oxidative burden. One of the key players in the genesis of reactive oxygen species (ROS) is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Based on initial experiments demonstrating a decreased...... inhibitory effect on NADPH oxidase activity in the presence of plasma from patients with CKD-5D after dialysis compared with before dialysis, we investigated the effect of 48 known and commercially available uraemic retention solutes on the enzymatic activity of NADPH oxidase. METHODS: Mononuclear leucocytes...

  4. Plant polyphenols and their anti-cariogenic properties: a review.

    Science.gov (United States)

    Ferrazzano, Gianmaria F; Amato, Ivana; Ingenito, Aniello; Zarrelli, Armando; Pinto, Gabriele; Pollio, Antonino

    2011-02-11

    Polyphenols constitute one of the most common groups of substances in plants. Polyphenolic compounds have been reported to have a wide range of biological activities, many of which are related to their conventional antioxidant action; however, increasing scientific knowledge has highlighted their potential activity in preventing oral disease, including the prevention of tooth decay. The aim of this review is to show the emerging findings on the anti-cariogenic properties of polyphenols, which have been obtained from several in vitro studies investigating the effects of these bioactive molecules against Streptococcus mutans, as well as in vivo studies. The analysis of the literature supports the anti-bacterial role of polyphenols on cariogenic streptococci, suggesting (1) a direct effect against S. mutans; (2) an interaction with microbial membrane proteins inhibiting the adherence of bacterial cells to the tooth surface; and (3) the inhibition of glucosyl transferase and amylase. However, more studies, particularly in vivo and in situ, are necessary to establish conclusive evidence for the effectiveness and the clinical applications of these compounds in the prevention of dental caries. It is essential to better determine the nature and distribution of these compounds in our diet and to identify which of the hundreds of existing polyphenols are likely to provide the greatest effects.

  5. Content of polyphenol compound in mangrove and macroalga extracts

    Science.gov (United States)

    Takarina, N. D.; Patria, M. P.

    2017-07-01

    Polyphenol or phenolic are compounds containing one or more hydroxyl group of the aromatic ring [1]. These compounds have some activities like antibacterial, antiseptic, and antioxidants. Natural resources like mangrove and macroalga were known containing these compounds. The purpose of the research was to investigate polyphenol content in mangrove and macroalga. Materials used in this research were mangrove (Avicennia sp.) leaves and the whole part of macroalga (Caulerpa racemosa). Samples were dried for 5 days then macerated in order to get an extract. Maceration were done using methanol for 48 hours (first) and 24 hours (second) continously. Polyphenol content was determined using phytochemical screening on both extracts. The quantitative test was carried out to determine catechin and tannin as polyphenol compound. The result showed that catechin was observed in both extracts while tannin in mangrove extract only. According to quantitative test, mangrove has a higher content of catechin and tannin which were 12.37-13.44 % compared to macroalga which was 2.57-4.58 %. Those indicated that both materials can be the source of polyphenol compound with higher content on mangrove. Moreover, according to this result, these resources can be utilized for advanced studies and human needs like medical drug.

  6. Anti-inflammatory effects of polyphenols in arthritis.

    Science.gov (United States)

    Oliviero, Francesca; Scanu, Anna; Zamudio-Cuevas, Yessica; Punzi, Leonardo; Spinella, Paolo

    2018-03-01

    Polyphenols have been extensively investigated with regard to their antioxidant, anti-inflammatory, and immunomodulant properties in many inflammatory chronic conditions. The aim of this review is to summarise how these compounds can modulate the inflammatory pathways which characterise the most prevalent arthropathies including osteoarthritis, rheumatoid arthritis and crystal-induced arthritis. Among polyphenols, epigallocatechin gallate, carnosol, hydroxytyrosol, curcumin, resveratrol, kaempferol and genistein have been the most widely investigated in arthritis. The most important results of the studies outlined in this article show how polyphenolic compounds are able to inhibit the expression and the release of a number of pro-inflammatory mediators and proteolytic enzymes, the activity of different transcriptional factors and the production of reactive oxygen species in vitro. Studies on animal models of rheumatoid arthritis, osteoarthritis and gout show interesting results in terms of reduced tissue damage, restored cartilage homeostasis, and decreased levels of uric acid, respectively. Despite the multiple protective effects of polyphenols, there are no dietary recommendations for patients affected by rheumatic diseases. Future studies, including intervention trials, should be conducted to determine the relevance of polyphenols consumption or supplementation in arthritis. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  7. Plant Polyphenols and Their Anti-Cariogenic Properties: A Review

    Directory of Open Access Journals (Sweden)

    Gabriele Pinto

    2011-02-01

    Full Text Available Polyphenols constitute one of the most common groups of substances in plants. Polyphenolic compounds have been reported to have a wide range of biological activities, many of which are related to their conventional antioxidant action; however, increasing scientific knowledge has highlighted their potential activity in preventing oral disease, including the prevention of tooth decay. The aim of this review is to show the emerging findings on the anti-cariogenic properties of polyphenols, which have been obtained from several in vitro studies investigating the effects of these bioactive molecules against Streptococcus mutans, as well as in vivo studies. The analysis of the literature supports the anti-bacterial role of polyphenols on cariogenic streptococci, suggesting (1 a direct effect against S. mutans; (2 an interaction with microbial membrane proteins inhibiting the adherence of bacterial cells to the tooth surface; and (3 the inhibition of glucosyl transferase and amylase. However, more studies, particularly in vivo and in situ, are necessary to establish conclusive evidence for the effectiveness and the clinical applications of these compounds in the prevention of dental caries. It is essential to better determine the nature and distribution of these compounds in our diet and to identify which of the hundreds of existing polyphenols are likely to provide the greatest effects.

  8. Dynamics of intracellular information decoding

    International Nuclear Information System (INIS)

    Kobayashi, Tetsuya J; Kamimura, Atsushi

    2011-01-01

    A variety of cellular functions are robust even to substantial intrinsic and extrinsic noise in intracellular reactions and the environment that could be strong enough to impair or limit them. In particular, of substantial importance is cellular decision-making in which a cell chooses a fate or behavior on the basis of information conveyed in noisy external signals. For robust decoding, the crucial step is filtering out the noise inevitably added during information transmission. As a minimal and optimal implementation of such an information decoding process, the autocatalytic phosphorylation and autocatalytic dephosphorylation (aPadP) cycle was recently proposed. Here, we analyze the dynamical properties of the aPadP cycle in detail. We describe the dynamical roles of the stationary and short-term responses in determining the efficiency of information decoding and clarify the optimality of the threshold value of the stationary response and its information-theoretical meaning. Furthermore, we investigate the robustness of the aPadP cycle against the receptor inactivation time and intrinsic noise. Finally, we discuss the relationship among information decoding with information-dependent actions, bet-hedging and network modularity

  9. Dynamics of intracellular information decoding.

    Science.gov (United States)

    Kobayashi, Tetsuya J; Kamimura, Atsushi

    2011-10-01

    A variety of cellular functions are robust even to substantial intrinsic and extrinsic noise in intracellular reactions and the environment that could be strong enough to impair or limit them. In particular, of substantial importance is cellular decision-making in which a cell chooses a fate or behavior on the basis of information conveyed in noisy external signals. For robust decoding, the crucial step is filtering out the noise inevitably added during information transmission. As a minimal and optimal implementation of such an information decoding process, the autocatalytic phosphorylation and autocatalytic dephosphorylation (aPadP) cycle was recently proposed. Here, we analyze the dynamical properties of the aPadP cycle in detail. We describe the dynamical roles of the stationary and short-term responses in determining the efficiency of information decoding and clarify the optimality of the threshold value of the stationary response and its information-theoretical meaning. Furthermore, we investigate the robustness of the aPadP cycle against the receptor inactivation time and intrinsic noise. Finally, we discuss the relationship among information decoding with information-dependent actions, bet-hedging and network modularity.

  10. Secretome of obligate intracellular Rickettsia

    Science.gov (United States)

    Gillespie, Joseph J.; Kaur, Simran J.; Rahman, M. Sayeedur; Rennoll-Bankert, Kristen; Sears, Khandra T.; Beier-Sexton, Magda; Azad, Abdu F.

    2014-01-01

    The genus Rickettsia (Alphaproteobacteria, Rickettsiales, Rickettsiaceae) is comprised of obligate intracellular parasites, with virulent species of interest both as causes of emerging infectious diseases and for their potential deployment as bioterrorism agents. Currently, there are no effective commercially available vaccines, with treatment limited primarily to tetracycline antibiotics, although others (e.g. josamycin, ciprofloxacin, chloramphenicol, and azithromycin) are also effective. Much of the recent research geared toward understanding mechanisms underlying rickettsial pathogenicity has centered on characterization of secreted proteins that directly engage eukaryotic cells. Herein, we review all aspects of the Rickettsia secretome, including six secretion systems, 19 characterized secretory proteins, and potential moonlighting proteins identified on surfaces of multiple Rickettsia species. Employing bioinformatics and phylogenomics, we present novel structural and functional insight on each secretion system. Unexpectedly, our investigation revealed that the majority of characterized secretory proteins have not been assigned to their cognate secretion pathways. Furthermore, for most secretion pathways, the requisite signal sequences mediating translocation are poorly understood. As a blueprint for all known routes of protein translocation into host cells, this resource will assist research aimed at uniting characterized secreted proteins with their apposite secretion pathways. Furthermore, our work will help in the identification of novel secreted proteins involved in rickettsial ‘life on the inside’. PMID:25168200

  11. HYPERTHERMIA, INTRACELLULAR FREE CALCIUM AND CALCIUM IONOPHORES

    NARCIS (Netherlands)

    STEGE, GJJ; WIERENGA, PK; KAMPINGA, HH; KONINGS, AWT

    1993-01-01

    It is shown that heat-induced increase of intracellular calcium does not correlate with hyperthermic cell killing. Six different cell lines were investigated; in four (EAT, HeLa S3, L5178Y-R and L5178Y-S) heat treatments killing 90% of the cells did not affect the levels of intracellular free

  12. Decoding NADPH oxidase 4 expression in human tumors

    Directory of Open Access Journals (Sweden)

    Jennifer L. Meitzler

    2017-10-01

    Full Text Available NADPH oxidase 4 (NOX4 is a redox active, membrane-associated protein that contributes to genomic instability, redox signaling, and radiation sensitivity in human cancers based on its capacity to generate H2O2 constitutively. Most studies of NOX4 in malignancy have focused on the evaluation of a small number of tumor cell lines and not on human tumor specimens themselves; furthermore, these studies have often employed immunological tools that have not been well characterized. To determine the prevalence of NOX4 expression across a broad range of solid tumors, we developed a novel monoclonal antibody that recognizes a specific extracellular region of the human NOX4 protein, and that does not cross-react with any of the other six members of the NOX gene family. Evaluation of 20 sets of epithelial tumors revealed, for the first time, high levels of NOX4 expression in carcinomas of the head and neck (15/19 patients, esophagus (12/18 patients, bladder (10/19 patients, ovary (6/17 patients, and prostate (7/19 patients, as well as malignant melanoma (7/15 patients when these tumors were compared to histologically-uninvolved specimens from the same organs. Detection of NOX4 protein upregulation by low levels of TGF-β1 demonstrated the sensitivity of this new probe; and immunofluorescence experiments found that high levels of endogenous NOX4 expression in ovarian cancer cells were only demonstrable associated with perinuclear membranes. These studies suggest that NOX4 expression is upregulated, compared to normal tissues, in a well-defined, and specific group of human carcinomas, and that its expression is localized on intracellular membranes in a fashion that could modulate oxidative DNA damage.

  13. Chemoenzymatic combination of glucose oxidase with titanium silicalite -1

    DEFF Research Database (Denmark)

    Vennestrøm, Peter Nicolai Ravnborg; Taarning, Esben; Christensen, Claus H.

    2010-01-01

    Zeozymes: A proof-of-concept is presented for the chemoenzymatic combination of titanium silicalite-1 zeolite with glucose oxidase. In this combination, glucose is oxidized to gluconic acid and the H2O2 byproduct formed in situ is used for the simultaneous oxidation of chemical substrates. Both...... a soluble glucose oxidase and a truly integrated heterogeneous combination whereby the oxidase enzyme is anchored onto the zeolite surface are reported....

  14. Plasma diamine oxidase levels in pregnancy complicated by threatened abortion.

    Science.gov (United States)

    Legge, M; Duff, G B

    1981-02-01

    Plasma diamine oxidase levels were assayed in 66 patients who presented with pregnancy complicated by threatened abortion. Levels within the normal range were associated with continuing pregnancies, whereas levels below the normal range were associated with subsequent abortion. Among those patients in whom gestation was greater than eight weeks, 66.6% of diamine oxidase levels correctly predicted the pregnancy outcome. Assay of the diamine oxidase levels at eight weeks of gestation or less gave little useful information.

  15. Plasma diamine oxidase levels in pregnancy complicated by threatened abortion.

    OpenAIRE

    Legge, M; Duff, G B

    1981-01-01

    Plasma diamine oxidase levels were assayed in 66 patients who presented with pregnancy complicated by threatened abortion. Levels within the normal range were associated with continuing pregnancies, whereas levels below the normal range were associated with subsequent abortion. Among those patients in whom gestation was greater than eight weeks, 66.6% of diamine oxidase levels correctly predicted the pregnancy outcome. Assay of the diamine oxidase levels at eight weeks of gestation or less ga...

  16. Gravity Responsive NADH Oxidase of the Plasma Membrane

    Science.gov (United States)

    Morre, D. James (Inventor)

    2002-01-01

    A method and apparatus for sensing gravity using an NADH oxidase of the plasma membrane which has been found to respond to unit gravity and low centrifugal g forces. The oxidation rate of NADH supplied to the NADH oxidase is measured and translated to represent the relative gravitational force exerted on the protein. The NADH oxidase of the plasma membrane may be obtained from plant or animal sources or may be produced recombinantly.

  17. The Reciprocal Interactions between Polyphenols and Gut Microbiota and Effects on Bioaccessibility

    Science.gov (United States)

    Ozdal, Tugba; Sela, David A.; Xiao, Jianbo; Boyacioglu, Dilek; Chen, Fang; Capanoglu, Esra

    2016-01-01

    As of late, polyphenols have increasingly interested the scientific community due to their proposed health benefits. Much of this attention has focused on their bioavailability. Polyphenol–gut microbiota interactions should be considered to understand their biological functions. The dichotomy between the biotransformation of polyphenols into their metabolites by gut microbiota and the modulation of gut microbiota composition by polyphenols contributes to positive health outcomes. Although there are many studies on the in vivo bioavailability of polyphenols, the mutual relationship between polyphenols and gut microbiota is not fully understood. This review focuses on the biotransformation of polyphenols by gut microbiota, modulation of gut microbiota by polyphenols, and the effects of these two-way mutual interactions on polyphenol bioavailability, and ultimately, human health. PMID:26861391

  18. Antioxidant and antibacterial activities of polyphenols from ethnomedicinal plants of Burkina Faso

    NARCIS (Netherlands)

    Karou, D.; Dicko, M.H.; Simpore, J.; Traore, A.S.

    2005-01-01

    Polyphenols from four medicinal plants of Burkina Faso, Combretum micranthum, Khaya senegalensis, Pterocarpus erinaceus and Sida acuta, were screened for their antioxidant and antimicrobial activities against pathogenic bacteria. The medicinal plants displayed different polyphenols contents and

  19. Interactions of blacktea polyphenols with human gut microbiota: implications for gut and cardiovascular health

    NARCIS (Netherlands)

    Duynhoven, van J.P.M.; Vaughan, E.E.; Dorsten, van F.; Gomez-Roldan, V.; Vos, de R.; Vervoort, J.J.M.; Hooft, van der J.J.J.; Roger, L.; Draijer, R.; Jacobs, D.M.

    2013-01-01

    Epidemiologic studies have convincingly associated consumption of black tea with reduced cardiovascular risk. Research on the bioactive molecules has traditionally been focused on polyphenols, such as catechins. Black tea polyphenols (BTPs), however, mainly consist of high-molecular-weight species

  20. Polyphenols as potential therapeutical agents against cardiovascular diseases.

    Science.gov (United States)

    Curin, Yann; Andriantsitohaina, Ramaroson

    2005-01-01

    Increasing evidence suggests that polyphenols from fruits, vegetables and beverages such as wine and tea may exert protective effects on the cardiovascular system. Indeed, research in the field of polyphenols points out their antioxidant and free radical scavenging properties, leading to lower low-density lipoprotein (LDL) oxidation and platelet aggregation. These compounds are also able to modulate the generation of nitric oxide (NO) from vascular endothelium and to interfere with the mechanisms leading to inflammation and endothelial apoptosis, contributing to the prevention of the endothelial dysfunction, known to play a central role in the pathogenesis of cardiovascular diseases. This article reviews the potential targets of polyphenols involved in the complex pathophysiological events occurring in cardiovascular diseases, such as hypertension, atherosclerosis and stroke.

  1. Sensorial properties of red wine polyphenols: Astringency and bitterness.

    Science.gov (United States)

    Soares, Susana; Brandão, Elsa; Mateus, Nuno; de Freitas, Victor

    2017-03-24

    Polyphenols have been the subject of numerous research over the past years, being referred as the nutraceuticals of modern life. The healthy properties of these compounds have been associated to a natural chemoprevention of 21st century major diseases such as cancer and neurodegenerative diseases (e.g. Parkinson's and Alzheimer's). This association led to an increased consumption of foodstuffs rich in these compounds such as red wine. Related to the ingestion of polyphenols are the herein revised sensorial properties (astringency and bitterness) which are not still pleasant. This review intends to be an outline both at a sensory as a molecular level of the mechanisms underlying astringency and bitterness of polyphenols. Up-to-date knowledge of this matter is discussed in detail.

  2. SEARCH PRODUCERS OF POLYPHENOLS AND SOME PIGMENTS AMONG BASIDIOMYCETES

    Directory of Open Access Journals (Sweden)

    Fedotov О. V.

    2014-02-01

    Full Text Available General content of polyphenols, carotenoids and melanin in basidiomycetes carpophorus was determined. 50 species were studied, 27 of which belong to the Polyporales form and 23 are to the Agaricales form. In order to determine the total content of phenolic substances spectrophotometric methods were used. Polyphenols were studied in alcoholic extracts through the modified Folin-Chokalteu procedure; melanin — by alkaline hydrolysis and calculated using a calibration curve (by pyrocatechol, carotenoids were studied in acetone extracts and calculated by the Vetshteyn formula. Statistical and cluster analysis of the data enabled to identify species of basidiomycetes that are perspective for biotechnology. The most promising in terms of total polyphenols, carotenoids and melanins of poliporal basidiomycetes are species Fomes fomentarius, Ganoderma applanatum, Ganoderma lucidum and Laetiporus sulphureus, and among agarikal fungi — Fistulina hepatica, Flammulina velutipes, Pleurotus ostreatus, Stropharia rugosoannulata, Agrocybe cylindracea and Tricholoma flavovirens. These species of Basidiomycetes were isolated in pure mycelia culture to find out their biosynthetic activity.

  3. Intracellular localization of Arabidopsis sulfurtransferases.

    Science.gov (United States)

    Bauer, Michael; Dietrich, Christof; Nowak, Katharina; Sierralta, Walter D; Papenbrock, Jutta

    2004-06-01

    Sulfurtransferases (Str) comprise a group of enzymes widely distributed in archaea, eubacteria, and eukaryota which catalyze the transfer of a sulfur atom from suitable sulfur donors to nucleophilic sulfur acceptors. In all organisms analyzed to date, small gene families encoding Str proteins have been identified. The gene products were localized to different compartments of the cells. Our interest concerns the localization of Str proteins encoded in the nuclear genome of Arabidopsis. Computer-based prediction methods revealed localization in different compartments of the cell for six putative AtStrs. Several methods were used to determine the localization of the AtStr proteins experimentally. For AtStr1, a mitochondrial localization was demonstrated by immunodetection in the proteome of isolated mitochondria resolved by one- and two-dimensional gel electrophoresis and subsequent blotting. The respective mature AtStr1 protein was identified by mass spectrometry sequencing. The same result was obtained by transient expression of fusion constructs with the green fluorescent protein in Arabidopsis protoplasts, whereas AtStr2 was exclusively localized to the cytoplasm by this method. Three members of the single-domain AtStr were localized in the chloroplasts as demonstrated by transient expression of green fluorescent protein fusions in protoplasts and stomata, whereas the single-domain AtStr18 was shown to be cytoplasmic. The remarkable subcellular distribution of AtStr15 was additionally analyzed by transmission electron immunomicroscopy using a monospecific antibody against green fluorescent protein, indicating an attachment to the thylakoid membrane. The knowledge of the intracellular localization of the members of this multiprotein family will help elucidate their specific functions in the organism.

  4. Intracellular calcium homeostasis and signaling.

    Science.gov (United States)

    Brini, Marisa; Calì, Tito; Ottolini, Denis; Carafoli, Ernesto

    2013-01-01

    Ca(2+) is a universal carrier of biological information: it controls cell life from its origin at fertilization to its end in the process of programmed cell death. Ca(2+) is a conventional diffusible second messenger released inside cells by the interaction of first messengers with plasma membrane receptors. However, it can also penetrate directly into cells to deliver information without the intermediation of first or second messengers. Even more distinctively, Ca(2+) can act as a first messenger, by interacting with a plasma membrane receptor to set in motion intracellular signaling pathways that involve Ca(2+) itself. Perhaps the most distinctive property of the Ca(2+) signal is its ambivalence: while essential to the correct functioning of cells, Ca(2+) becomes an agent that mediates cell distress, or even (toxic) cell death, if its concentration and movements inside cells are not carefully tuned. Ca(2+) is controlled by reversible complexation to specific proteins, which could be pure Ca(2+) buffers, or which, in addition to buffering Ca(2+), also decode its signal to pass it on to targets. The most important actors in the buffering of cell Ca(2+) are proteins that transport it across the plasma membrane and the membrane of the organelles: some have high Ca(2+) affinity and low transport capacity (e.g., Ca(2+) pumps), others have opposite properties (e.g., the Ca(2+) uptake system of mitochondria). Between the initial event of fertilization, and the terminal event of programmed cell death, the Ca(2+) signal regulates the most important activities of the cell, from the expression of genes, to heart and muscle contraction and other motility processes, to diverse metabolic pathways involved in the generation of cell fuels.

  5. SNARE zippering is hindered by polyphenols in the neuron

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yoosoo [Department of Genetic Engineering and Center for Human Interface Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Biomedical Research Institute, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Kim, Se-Hyun; Heo, Paul; Kong, Byoungjae; Shin, Jonghyeok; Jung, Young-Hun; Yoon, Keejung; Chung, Woo-Jae [Department of Genetic Engineering and Center for Human Interface Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Shin, Yeon-Kyun [Biomedical Research Institute, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011 (United States); Kweon, Dae-Hyuk, E-mail: dhkweon@skku.edu [Department of Genetic Engineering and Center for Human Interface Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-07-18

    Highlights: • Membrane fusion driven by SNARE complex is hindered by several polyphenols. • Distinctive inhibitory effect of each polyphenol on SNARE zippering in neuron was examined. • FRET between fluorescence protein-tagged SNAREs probed well SNARE zippering in PC12 cells. • Delphinidin and cyanidin inhibit N-terminal SNARE nucleation in Ca{sup 2+}-independent manner. • Myricetin inhibits Ca{sup 2+}-dependent transmembrane association of SNARE complex. - Abstract: Fusion of synaptic vesicles with the presynaptic plasma membrane in the neuron is mediated by soluble N-ethylmaleimide-sensitive fusion protein-attachment protein receptor (SNARE) proteins. SNARE complex formation is a zippering-like process which initiates at the N-terminus and proceeds to the C-terminal membrane-proximal region. Previously, we showed that this zippering-like process is regulated by several polyphenols, leading to the arrest of membrane fusion and the inhibition of neuroexocytosis. In vitro studies using purified SNARE proteins reconstituted in liposomes revealed that each polyphenol uniquely regulates SNARE zippering. However, the unique regulatory effect of each polyphenol in cells has not yet been examined. In the present study, we observed SNARE zippering in neuronal PC12 cells by measuring the fluorescence resonance energy transfer (FRET) changes of a cyan fluorescence protein (CFP) and a yellow fluorescence protein (YFP) fused to the N-termini or C-termini of SNARE proteins. We show that delphinidin and cyanidin inhibit the initial N-terminal nucleation of SNARE complex formation in a Ca{sup 2+}-independent manner, while myricetin inhibits Ca{sup 2+}-dependent transmembrane domain association of the SNARE complex in the cell. This result explains how polyphenols exhibit botulinum neurotoxin-like activity in vivo.

  6. Mass spectrometry in grape and wine chemistry. Part I: polyphenols.

    Science.gov (United States)

    Flamini, Riccardo

    2003-01-01

    Mass spectrometry, had and still has, a very important role for research and quality control in the viticulture and enology field, and its analytical power is relevant for structural studies on aroma and polyphenolic compounds. Polyphenols are responsible for the taste and color of wine, and confer astringency and structure to the beverage. The knowledge of the anthocyanic structure is very important to predict the aging attitude of wine, and to attempt to resolve problems about color stability. Moreover, polyphenols are the main compounds related to the benefits of wine consumption in the diet, because of their properties in the treatment of circulatory disorders such as capillary fragility, peripheral chronic venous insufficiency, and microangiopathy of the retina. Liquid Chromatography-Mass Spectrometry (LC-MS) techniques are nowadays the best analytical approach to study polyphenols in grape extracts and wine, and are the most effective tool in the study of the structure of anthocyanins. The MS/MS approach is a very powerful tool that permits anthocyanin aglycone and sugar moiety characterization. LC-MS allows the characterization of complex structures of grape polyphenols, such as procyanidins, proanthocyanidins, prodelphinidins, and tannins, and provides experimental evidence for structures that were previously only hypothesized. The matrix-assisted-laser-desorption-ionization-time-of-flight (MALDI-TOF) technique is suitable to determine the presence of molecules of higher molecular weight with high accuracy, and it has been applied with success to study procyanidin oligomers up to heptamers in the reflectron mode, and up to nonamers in the linear mode. The levels of resveratrol in wine, an important polyphenol well-known for its beneficial effects, have been determined by SPME and LC-MS, and the former approach led to the best results in terms of sensitivity. Copyright 2003 Wiley Periodicals, Inc.

  7. The scavenging effects of tea polyphenol and quercetin on active oxygen species

    International Nuclear Information System (INIS)

    Fang Ruoying; Cheng Jiwu; Hu Tianxi; Tu Tiechen; Dong Jirong; Wang Wenfeng; Lin Nianyun

    1993-01-01

    The abilities of scavenging active oxygen species, O 2 free radical and OH., by tea polyphenols and quercetin have been studied by chemiluminescence, ESR and pulse radiolysis. Tea polyphenols and quercetin are all phenolic antioxidants. The synergetic studies show that both tea polyphenols and quercetin are strong free radical scavengers. Tea polyphenols are better than quercetin. the results from CL studies are in good accord with those from ESR and PR studies

  8. [Review: plant polyphenols modulate lipid metabolism and related molecular mechanism].

    Science.gov (United States)

    Dai, Yan-li; Zou, Yu-xiao; Liu, Fan; Li, Hong-zhi

    2015-11-01

    Lipid metabolism disorder is an important risk factor to obesity, hyperlipidemia and type 2 diabetes as well as other chronic metabolic disease. It is also a key target in preventing metabolic syndrome, chronic disease prevention. Plant polyphenol plays an important role in maintaining or improving lipid profile in a variety of ways. including regulating cholesterol absorption, inhibiting synthesis and secretion of triglyceride, and lowering plasma low density lipoprotein oxidation, etc. The purpose of this article is to review the lipid regulation effects of plant polyphenols and its related mechanisms.

  9. Modulation of neurotrophic signaling pathways by polyphenols

    Directory of Open Access Journals (Sweden)

    Moosavi F

    2015-12-01

    Full Text Available Fatemeh Moosavi,1,2 Razieh Hosseini,1,2 Luciano Saso,3 Omidreza Firuzi1 1Medicinal and Natural Products Chemistry Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; 2Department of Pharmacology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran; 3Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Rome, Italy Abstract: Polyphenols are an important class of phytochemicals, and several lines of evidence have demonstrated their beneficial effects in the context of a number of pathologies including neurodegenerative disorders such as Alzheimer’s and Parkinson’s disease. In this report, we review the studies on the effects of polyphenols on neuronal survival, growth, proliferation and differentiation, and the signaling pathways involved in these neurotrophic actions. Several polyphenols including flavonoids such as baicalein, daidzein, luteolin, and nobiletin as well as nonflavonoid polyphenols such as auraptene, carnosic acid, curcuminoids, and hydroxycinnamic acid derivatives including caffeic acid phentyl ester enhance neuronal survival and promote neurite outgrowth in vitro, a hallmark of neuronal differentiation. Assessment of underlying mechanisms, especially in PC12 neuronal-like cells, reveals that direct agonistic effect on tropomyosin receptor kinase (Trk receptors, the main receptors of neurotrophic factors including nerve growth factor (NGF and brain-derived neurotrophic factor (BDNF explains the action of few polyphenols such as 7,8-dihydroxyflavone. However, several other polyphenolic compounds activate extracellular signal-regulated kinase (ERK and phosphoinositide 3-kinase (PI3K/Akt pathways. Increased expression of neurotrophic factors in vitro and in vivo is the mechanism of neurotrophic action of flavonoids such as scutellarin, daidzein, genistein, and fisetin, while compounds like apigenin and ferulic acid increase cyclic adenosine monophosphate

  10. NADPH oxidase: an enzyme for multicellularity?

    Science.gov (United States)

    Lalucque, Hervé; Silar, Philippe

    2003-01-01

    Multicellularity has evolved several times during the evolution of eukaryotes. One evolutionary pressure that permits multicellularity relates to the division of work, where one group of cells functions as nutrient providers and the other in specialized roles such as defence or reproduction. This requires signalling systems to ensure harmonious development of multicellular structures. Here, we show that NADPH oxidases are specifically present in organisms that differentiate multicellular structures during their life cycle and are absent from unicellular life forms. The biochemical properties of these enzymes make them ideal candidates for a role in intercellular signalling.

  11. Development of polyphenolic nanoparticles for biomedical applications

    Science.gov (United States)

    Cheng, Huaitzung Andrew

    Polymeric nanoparticles have a wide range of applications, particularly as drug delivery and diagnostic agents, and tannins have been regarded as a promising building block for redox and pH responsive systems. Tannins are a class of naturally occurring polyphenols commonly produced by plants and are found in many of our consumables like teas, spices, fresh fruits, and vegetables. Many of the health benefits associated with these foods are a result of their high tannin contents and the many different types of tannins found in various plants have demonstrated therapeutic potentials for conditions ranging from cardiovascular disease and diabetes to ulcers and cancer. Diets rich in tannins have been associated with lower blood pressure in patients with hypertension. The plurality of phenols in tannins also makes them powerful antioxidants and as a result, there is a lot of interest in taking advantage of their self-assembling abilities to make redox and pH responsive drug delivery systems. However, the benefit of natural tannins is limited by their instability in physiological conditions. Furthermore, there is limited control over molecular weight and reactivity of the phenolic content of plant extracts. Herein we report the novel synthesis of pseudotannins with control over molecular weight and reactivity of phenolic moieties. These pseudotannins have can form nanoscale interpolymer complexes under physiological conditions and have demonstrated antioxidative potential. Furthermore, pseudotannin IPCs have been shown to be responsive to physiologically relevant oxidation as well as the ability to easily incorporate cell targeting peptides, fluorescent tags, and MRI contrast agents. The work presented here describes how pseudotannins would be ideally suited to minimally invasive techniques for diagnosing atherosclerotic plaques and targeting triple negative breast cancer. We demonstrate that pseudotannin can very easily and quickly form nanoscale particles that are small

  12. Estimated Dietary Polyphenol Intake and Major Food and Beverage Sources among Elderly Japanese

    Directory of Open Access Journals (Sweden)

    Chie Taguchi

    2015-12-01

    Full Text Available Estimating polyphenol intake contributes to the understanding of polyphenols’ health benefits. However, information about human polyphenol intake is scarce, especially in the elderly. This study aimed to estimate the dietary intake and major sources of polyphenols and to determine whether there is any relationship between polyphenol intake and micronutrient intake in healthy elderly Japanese. First, 610 subjects (569 men, 41 women; aged 67.3 ± 6.1 years completed food frequency questionnaires. We then calculated their total polyphenol intake using our polyphenol content database. Their average total polyphenol intake was 1492 ± 665 mg/day, the greatest part of which was provided by beverages (79.1%. The daily polyphenol intake differed largely among individuals (183–4854 mg/day, also attributable mostly to beverage consumption. Coffee (43.2% and green tea (26.6% were the major sources of total polyphenol; the top 20 food items accounted for >90%. The polyphenol intake did not strongly correlate with the intake of any micronutrient, suggesting that polyphenols may exert health benefits independently of nutritional intake. The polyphenol intake in this elderly population was slightly higher than previous data in Japanese adults, and beverages such as coffee and green tea contributed highly to the intake.

  13. The influence of virus diseases on grape polyphenols of cv. 'Refosk'

    International Nuclear Information System (INIS)

    Tomazic, I.; Vrhovsek, U.; Korosec-Koruza, Z.

    2003-01-01

    External stimuli such as microbial infections, ultraviolet radiation, and chemical stressors can modulate the synthesis of polyphenols in the plants. Cv. 'Refosk' was used to show the influence of the GLRaV-1 and rugose wood (RW) on the polyphenols in grape. The infection shifted polyphenols from seeds to grape skins but had no impact on anthocyanins

  14. A Prospective Evaluation of Plasma Polyphenol Levels and Colon Cancer Risk

    DEFF Research Database (Denmark)

    Murphy, Neil; Achaintre, David; Zamora-Ros, Raul

    2018-01-01

    Polyphenols have been shown to exert biological activity in experimental models of colon cancer; however, human data linking specific polyphenols to colon cancer is limited. We assessed the relationship between pre-diagnostic plasma polyphenols and colon cancer risk in a case-control study nested...

  15. The amine oxidase inhibitor phenelzine limits lipogenesis in adipocytes without inhibiting insulin action on glucose uptake.

    Science.gov (United States)

    Carpéné, Christian; Grès, Sandra; Rascalou, Simon

    2013-06-01

    The antidepressant phenelzine is a monoamine oxidase inhibitor known to inhibit various other enzymes, among them semicarbazide-sensitive amine oxidase (currently named primary amine oxidase: SSAO/PrAO), absent from neurones but abundant in adipocytes. It has been reported that phenelzine inhibits adipocyte differentiation of cultured preadipocytes. To further explore the involved mechanisms, our aim was to study in vitro the acute effects of phenelzine on de novo lipogenesis in mature fat cells. Therefore, glucose uptake and incorporation into lipid were measured in mouse adipocytes in response to phenelzine, other hydrazine-based SSAO/PrAO-inhibitors, and reference agents. None of the inhibitors was able to impair the sevenfold activation of 2-deoxyglucose uptake induced by insulin. Phenelzine did not hamper the effect of lower doses of insulin. However, insulin-stimulated glucose incorporation into lipids was dose-dependently inhibited by phenelzine and pentamidine, but not by semicarbazide or BTT2052. In contrast, all these SSAO/PrAO inhibitors abolished the transport and lipogenesis stimulation induced by benzylamine. These data indicate that phenelzine does not inhibit glucose transport, the first step of lipogenesis, but inhibits at 100 μM the intracellular triacylglycerol assembly, consistently with its long-term anti-adipogenic effect and such rapid action was not found with all the hydrazine derivatives tested. Therefore, the alterations of body weight control consecutive to the use of this antidepressant drug might be not only related to central effects on food intake/energy expenditure, but could also depend on its direct action in adipocytes. Nonetheless, phenelzine antilipogenic action is not merely dependent on SSAO/PrAO inhibition.

  16. Astragaloside IV prevents damage to human mesangial cells through the inhibition of the NADPH oxidase/ROS/Akt/NF‑κB pathway under high glucose conditions.

    Science.gov (United States)

    Sun, Li; Li, Weiping; Li, Weizu; Xiong, Li; Li, Guiping; Ma, Rong

    2014-07-01

    Glomerular hypertrophy and hyperfiltration are the two major pathological characteristics of the early stages of diabetic nephropathy (DN), which are respectively related to mesangial cell (MC) proliferation and a decrease in calcium influx conducted by canonical transient receptor potential cation channel 6 (TRPC6). The marked increase in the production of reactive oxygen species (ROS) induced by hyperglycemia is the main sponsor of multiple pathological pathways in DN. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is an important source of ROS production in MCs. Astragaloside IV (AS‑IV) is an active ingredient of Radix Astragali which has a potent antioxidative effect. In this study, we aimed to investigate whether high glucose (HG)‑induced NADPH oxidase activation and ROS production contribute to MC proliferation and the downregulation of TRPC6 expression; we also wished to determine the effects of AS‑IV on MCs under HG conditions. Using a human glomerular mesangial cell line, we found that treatment with AS‑IV for 48 h markedly attenuated HG‑induced proliferation and the hypertrophy of MCs in a dose‑dependent manner. The intracellular ROS level was also markedly reduced following treatment with AS‑IV. In addition, the enhanced activity of NADPH oxidase and the expression level of NADPH oxidase 4 (Nox4) protein were decreased. Treatment with AS‑IV also inhibited the phosphorylation level of Akt and IκBα in the MCs. In addition, TRPC6 protein expression and the intracellular free calcium concentration were also markedly reduced following treatment with AS‑IV under HG conditions. These results suggest that AS‑IV inhibits HG‑induced mesangial cell proliferation and glomerular contractile dysfunction through the NADPH oxidase/ROS/Akt/nuclear factor‑κB (NF‑κB) pathway, providing a new perspective for the clinical treatment of DN.

  17. Glucose oxidase probe as a surface-enhanced Raman scattering sensor for glucose.

    Science.gov (United States)

    Qi, Guohua; Wang, Yi; Zhang, Biying; Sun, Dan; Fu, Cuicui; Xu, Weiqing; Xu, Shuping

    2016-10-01

    Glucose oxidase (GOx) possessing a Raman-active chromophore (flavin adenine dinucleotide) is used as a signal reporter for constructing a highly specific "turn off" surface-enhanced Raman scattering (SERS) sensor for glucose. This sensing chip is made by the electrostatic assembly of GOx over silver nanoparticle (Ag NP)-functionalized SERS substrate through a positively charged polyelectrolyte linker under the pH of 6.86. To trace glucose in blood serum, owing to the reduced pH value caused by the production of gluconic acid in the GOx-catalyzed oxidation reaction, the bonding force between GOx and polyelectrolyte weakens, making GOx drop off from the sensing chip. As a result, the SERS intensity of GOx on the chip decreases along with the concentration of glucose. This glucose SERS sensor exhibits excellent selectivity based on the specific GOx/glucose catalysis reaction and high sensitivity to 1.0 μM. The linear sensing range is 2.0-14.0 mM, which also meets the requirement on the working range of the human blood glucose detection. Using GOx as a probe shows superiority over other organic probes because GOx almost has no toxicity to the biological system. This sensing mechanism can be applied for intracellular in vivo SERS monitoring of glucose in the future. Graphical abstract Glucose oxidase is used as a Raman signal reporter for constructing a highly specific glucose surface-enhanced Raman scattering (SERS) sensor.

  18. The NADPH oxidase inhibitor apocynin induces nitric oxide synthesis via oxidative stress

    International Nuclear Information System (INIS)

    Riganti, Chiara; Costamagna, Costanzo; Doublier, Sophie; Miraglia, Erica; Polimeni, Manuela; Bosia, Amalia; Ghigo, Dario

    2008-01-01

    We have recently shown that apocynin elicits an oxidative stress in N11 mouse glial cells and other cell types. Here we report that apocynin increased the accumulation of nitrite, the stable derivative of nitric oxide (NO), in the extracellular medium of N11 cell cultures, and the NO synthase (NOS) activity in cell lysates. The increased synthesis of NO was associated with increased expression of inducible NOS (iNOS) mRNA, increased nuclear translocation of the redox-sensitive transcription factor NF-κB and decreased intracellular level of its inhibitor IkBα. These effects, accompanied by increased production of H 2 O 2 , were very similar to those observed after incubation with bacterial lipopolysaccharide (LPS) and were inhibited by catalase. These results suggest that apocynin, similarly to LPS, induces increased NO synthesis by eliciting a generation of reactive oxygen species (ROS), which in turn causes NF-κB activation and increased expression of iNOS. Therefore, the increased bioavailability of NO reported in the literature after in vivo or in vitro treatments with apocynin might depend, at least partly, on the drug-elicited induction of iNOS, and not only on the inhibition of NADPH oxidase and the subsequent decreased scavenging of NO by oxidase-derived ROS, as it is often supposed

  19. Involvement of NADH Oxidase in Competition and Endocarditis Virulence in Streptococcus sanguinis.

    Science.gov (United States)

    Ge, Xiuchun; Yu, Yang; Zhang, Min; Chen, Lei; Chen, Weihua; Elrami, Fadi; Kong, Fanxiang; Kitten, Todd; Xu, Ping

    2016-05-01

    Here, we report for the first time that the Streptococcus sanguinis nox gene encoding NADH oxidase is involved in both competition with Streptococcus mutans and virulence for infective endocarditis. An S. sanguinis nox mutant was found to fail to inhibit the growth of Streptococcus mutans under microaerobic conditions. In the presence of oxygen, the recombinant Nox protein of S. sanguinis could reduce oxygen to water and oxidize NADH to NAD(+) The oxidation of NADH to NAD(+) was diminished in the nox mutant. The nox mutant exhibited decreased levels of extracellular H2O2; however, the intracellular level of H2O2 in the mutant was increased. Furthermore, the virulence of the nox mutant was attenuated in a rabbit endocarditis model. The nox mutant also was shown to be more sensitive to blood killing, oxidative and acid stresses, and reduced growth in serum. Thus, NADH oxidase contributes to multiple phenotypes related to competitiveness in the oral cavity and systemic virulence. Copyright © 2016 Ge et al.

  20. Chromatographic Methods for the Analysis of Polyphenols in Wines

    Directory of Open Access Journals (Sweden)

    Medić-Šarić, M.

    2009-03-01

    Full Text Available Wine is an excellent source of various classes of polyphenols, including phenolic acids, flavonoids, and trihydroxystilbene resveratrol (Fig.1. Polyphenols play a major role in wine quality since they contribute to the sensory characteristics of wine, particularly color and astringency. A recent interest in these substances has been stimulated by abundant evidence of their beneficial effects on human health, such as anticarcinogenic, antiinflamatory and antimicrobial activities. Therefore, numerous studies have been performed in the attempt to analyze polyphenols in wine. This paper reviews the current advances in the determination of polyphenols in wine by the major chromatographic techniques such as thin-layer chromatography (TLC and high-performance liquid chromatography (HPLC.The great complexity of the polyphenolic content of wine and the difficulty in obtaining some of the standards usually require sample preparation before analysis. Two methods for sample preparation, liquid-liquid extraction and solid-phase extraction, are most commonly applied. Hydrolysis is applied frequently, but not exclusively, to remove the sugar moieties from glycosides.TLC on silica gel plates is useful for the rapid and low-cost separation and identification of the polyphenols present in wine (Fig. 2. Densitometric quantitative analysis of polyphenols in wine extracts is usually performed by scanning the TLC plates with UV light at wavelengths of 350–365 nm or 250–260 nm (Fig. 3. For the evaluation of the most efficient mobile phase and an optimal choice of the combination of two or more mobile phases, two methods may be applied: information theory and numerical taxonomy. HPLC currently represents the most popular technique for the analysis of polyphenols in wine. For this purpose, a reversed-phase HPLC method that uses gradient elution with binary elution system is usually employed. Routine detection is based on measurement of UV-Vis absorption with a diode

  1. Simultaneous ultrasound-assisted water extraction and β-cyclodextrin encapsulation of polyphenols from Mangifera indica stem bark in counteracting TNFα-induced endothelial dysfunction.

    Science.gov (United States)

    Mura, Marzia; Palmieri, Daniela; Garella, Davide; Di Stilo, Antonella; Perego, Patrizia; Cravotto, Giancarlo; Palombo, Domenico

    2015-01-01

    This study proposes an alternative technique to prevent heat degradation induced by classic procedures of bioactive compound extraction, comparing classical maceration/decoction in hot water of polyphenols from Mango (Mangifera indica L.) (MI) with ultrasound-assisted extraction (UAE) in a water solution of β-cyclodextrin (β-CD) at room temperature and testing their biological activity on TNFα-induced endothelial dysfunction. Both extracts counteracted TNFα effects on EAhy926 cells, down-modulating interleukin-6, interleukin-8, cyclooxygenase-2 and intracellular adhesion molecule-1, while increasing endothelial nitric oxide synthase levels. β-CD extract showed higher efficacy in improving endothelial function. These effects were abolished after pre-treatment with the oestrogen receptor inhibitor ICI1182,780. Moreover, the β-CD extract induced Akt activation and completely abolished the TNFα-induced p38MAPK phosphorylation. UAE and β-CD encapsulation provide an efficient extraction protocol that increases polyphenol bioavailability. Polyphenols from MI play a protective role on endothelial cells and may be further considered as oestrogen-like molecules with vascular protective properties.

  2. Crystallization of carbohydrate oxidase from Microdochium nivale

    International Nuclear Information System (INIS)

    Dušková, Jarmila; Dohnálek, Jan; Skálová, Tereza; Østergaard, Lars Henrik; Fuglsang, Claus Crone; Kolenko, Petr; Štěpánková, Andrea; Hašek, Jindřich

    2009-01-01

    Industrially used carbohydrate oxidase was successfully crystallized in several forms, diffraction data suitable for structural analysis were collected. Microdochium nivale carbohydrate oxidase was produced by heterologous recombinant expression in Aspergillus oryzae, purified and crystallized. The enzyme crystallizes with varying crystal morphologies depending on the crystallization conditions. Several different crystal forms were obtained using the hanging-drop vapour-diffusion method, two of which were used for diffraction measurements. Hexagon-shaped crystals (form I) diffracted to 2.66 Å resolution, with unit-cell parameters a = b = 55.7, c = 610.4 Å and apparent space group P6 2 22. Analysis of the data quality showed almost perfect twinning of the crystals. Attempts to solve the structure by molecular replacement did not give satisfactory results. Recently, clusters of rod-shaped crystals (form II) were grown in a solution containing PEG MME 550. These crystals belonged to the monoclinic system C2, with unit-cell parameters a = 132.9, b = 56.6, c = 86.5 Å, β = 95.7°. Data sets were collected to a resolution of 2.4 Å. The structure was solved by the molecular-replacement method. Model refinement is currently in progress

  3. Cytochemical Localization of Glucose Oxidase in Peroxisomes of Aspergillus niger

    NARCIS (Netherlands)

    Veenhuis, Marten; Dijken, Johannes Pieter van

    1980-01-01

    The subcellular localization of glucose oxidase (E.C. 1.1.3.4) in mycelia of Aspergillus niger has been investigated using cytochemical staining techniques. Mycelia from fermenter cultures, which produced gluconic acid from glucose, contained elevated levels of glucose oxidase and catalase. Both

  4. Xanthine oxidase in human skeletal muscle following eccentric exercise

    DEFF Research Database (Denmark)

    Hellsten, Ylva; Frandsen, Ulrik; Orthenblad, N.

    1997-01-01

    the increase in xanthine oxidase in the muscle there were no detectable changes in the levels of muscle malondialdehyde or in plasma antioxidant capacity up to 4 days post-exercise. 5. It is concluded that eccentric exercise leads to an increased level of xanthine oxidase in human muscle and that the increase...

  5. Laboratory-evolved vanillyl-alcohol oxidase produces natural vanillin

    NARCIS (Netherlands)

    Heuvel, van den R.H.H.; Berg, van den W.A.M.; Rovida, S.; Berkel, van W.J.H.

    2004-01-01

    The flavoenzyme vanillyl-alcohol oxidase was subjected to random mutagenesis to generate mutants with enhanced reactivity to creosol (2-methoxy-4-methylphenol). The vanillyl-alcohol oxidase-mediated conversion of creosol proceeds via a two-step process in which the initially formed vanillyl alcohol

  6. Optimization of glucose oxidase production by Aspergillus niger

    African Journals Online (AJOL)

    user

    2011-02-28

    Feb 28, 2011 ... manganese, cobalt, thioglycolic acid, and gluconic acid according to (Liu et al., .... In this experiment duplicate media of glucose 10% were adjusted at different ... Glucose oxidase as a pharmaceutical anti oxidant Drug. Devt. ... Plush KS, Hellmuth K, Rinas U (1996). kinetics of glucose oxidase excretion by ...

  7. 21 CFR 866.2420 - Oxidase screening test for gonorrhea.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Oxidase screening test for gonorrhea. 866.2420... screening test for gonorrhea. (a) Identification. An oxidase screening test for gonorrhea is an in vitro... of gonorrhea. (b) Classification. Class III (premarket approval) (transitional device). (c) Date PMA...

  8. Effects of Greek legume plant extracts on xanthine oxidase, catalase and superoxide dismutase activities.

    Science.gov (United States)

    Spanou, Chrysoula I; Veskoukis, Aristidis S; Stagos, Dimitrios; Liadaki, Kalliopi; Aligiannis, Nectarios; Angelis, Apostolos; Skaltsounis, Alexios-Leandros; Anastasiadi, Maria; Haroutounian, Serkos A; Kouretas, Dimitrios

    2012-03-01

    Legumes are considered to have beneficial health implications, which have been attributed to their phytochemical content. Polyphenols are considered the most important phytochemical compounds extensively studied for their antioxidant properties. The aim of the present study was to examine the effects of potent antioxidant legume plant extracts on xanthine oxidase (XO), catalase (CAT) and superoxide dismutase (SOD) activities. XO exerts a dual role, as it is the major contributor of free radicals during exercise while it generates uric acid, the most potent antioxidant molecule in plasma. CAT and SOD are two of the main enzymes of the antioxidant defence of tissues. We demonstrate that the majority of the extracts inhibited XO activity, but they had no effect on CAT inhibition and SOD induction when used at low concentrations. These results imply that the tested extracts may be considered as possible source of novel XO inhibitors. However, we have shown that allopurinol administration, a known XO inhibitor, before exercise reduces performance and induces oxidative stress in rats. Considering the fact that the extracts examined had an inhibitory effect on XO activity, possibly posing a restriction in their characterization as antioxidants, phytochemical antioxidant administration before exercise should probably be reconsidered.

  9. Nanoparticles for intracellular-targeted drug delivery

    International Nuclear Information System (INIS)

    Paulo, Cristiana S O; Pires das Neves, Ricardo; Ferreira, Lino S

    2011-01-01

    Nanoparticles (NPs) are very promising for the intracellular delivery of anticancer and immunomodulatory drugs, stem cell differentiation biomolecules and cell activity modulators. Although initial studies in the area of intracellular drug delivery have been performed in the delivery of DNA, there is an increasing interest in the use of other molecules to modulate cell activity. Herein, we review the latest advances in the intracellular-targeted delivery of short interference RNA, proteins and small molecules using NPs. In most cases, the drugs act at different cellular organelles and therefore the drug-containing NPs should be directed to precise locations within the cell. This will lead to the desired magnitude and duration of the drug effects. The spatial control in the intracellular delivery might open new avenues to modulate cell activity while avoiding side-effects.

  10. Biological synthesis and characterization of intracellular gold ...

    Indian Academy of Sciences (India)

    thods of reduction of metal ions using plants or microorganisms are often ... have several advantages over bacteria, they are often pre- ferred. ... in static condition for a period of 7 days. ... work was focused on the production of intracellular gold.

  11. Cocoa and Dark Chocolate Polyphenols: From Biology to Clinical Applications.

    Science.gov (United States)

    Magrone, Thea; Russo, Matteo Antonio; Jirillo, Emilio

    2017-01-01

    It is well known that cocoa and dark chocolate possess polyphenols as major constituents whose dietary consumption has been associated to beneficial effects. In fact, cocoa and dark chocolate polyphenols exert antioxidant and anti-inflammatory activities switching on some important signaling pathways such as toll-like receptor 4/nuclear factor κB/signal transducer and activator of transcription. In particular, cocoa polyphenols induce release of nitric oxide (NO) through activation of endothelial NO synthase which, in turn, accounts for vasodilation and cardioprotective effects. In the light of the above described properties, a number of clinical trials based on the consumption of cocoa and dark chocolate have been conducted in healthy subjects as well as in different categories of patients, such as those affected by cardiovascular, neurological, intestinal, and metabolic pathologies. Even if data are not always concordant, modifications of biomarkers of disease are frequently associated to improvement of clinical manifestations. Quite interestingly, following cocoa and dark chocolate ingestion, cocoa polyphenols also modulate intestinal microbiota, thus leading to the growth of bacteria that trigger a tolerogenic anti-inflammatory pathway in the host. Finally, many evidences encourage the consumption of cocoa and dark chocolate by aged people for the recovery of the neurovascular unit.

  12. Polyphenols as Possible Markers of Botanical Origin of Honey.

    Science.gov (United States)

    Gašić, Uroš M; Milojković-Opsenica, Dušanka M; Tešić, Živoslav Lj

    2017-07-01

    In recent years, the botanical and geographical origin of food has become an important topic in the context of food quality and safety, as well as consumer protection, in accordance with international standards. Finding chemical markers, especially phytochemicals, characteristic for some kind of food is the subject of interest of a significant number of researchers in the world. This paper is focused on the use of polyphenols as potential markers for the determination of botanical origin of honey. It includes a review of the polyphenols present in various honey samples and the methods for their separation and identification. Special emphasis in this paper is placed on the identification of honey polyphenols using advanced LC-MS techniques in order to find specific markers of botanical origin of honey. In this regard, this study gives an overview of the literature that describes the use of LC-MS techniques for the isolation and determination of honey polyphenols. This review focuses on the research performed in the past two decades.

  13. Forging a modern generation of polyphenol-based therapeutics.

    Science.gov (United States)

    Wright, Bernice

    2013-06-01

    The long-standing debate that polyphenol secondary metabolites from dietary plants are important nutritional components continues due to compelling evidence for their abilities to ameliorate degenerative conditions including, cancer, neurological disorders and cardiovascular disease. The clinical use of polyphenols is not, however, mainstream as issues regarding poor selectivity, dosage, toxicity and delivery methods are unresolved. The paper by Rieder et al. suggests that the lack of selectivity, at least for the stilbene, resveratrol, may not be a major limiting factor. The present commentary is a critique of this significant finding that is focused on deciding how the use of resveratrol as clinical medicine could be advanced, and how this new information integrates with current knowledge of polyphenol physiological effects. This commentary suggests that the multi-target nature of polyphenols may be translated into reliable therapy using the current systems/network pharmacology approach concerned with developing viable therapeutic agents that achieve specific effects through interactions with a wide array of targets. This article is a commentary on Rieder et al., pp. 1244-1258 of BJP 167:6. To view this paper visit http://dx.doi.org/10.1111/j.1476-5381.2012.02063.x. © 2013 The Author. British Journal of Pharmacology © 2013 The British Pharmacological Society.

  14. Cyanate Ester Composite Resins Derived from Renewable Polyphenol Sources

    Science.gov (United States)

    2011-03-16

    NDGA). Other promising polyphenols are resveratrol, a well-known antioxidant found in grape skins and extracted from Japanese Knotweed, and curcumin ...the phenolic rings of 4- methyl-2-methoxyphenol,18 a procedure detailed by Marques and coworkers19 uses the methylene chloride soluble permanganate

  15. Antioxidant, Antibacterial and Cell Toxicity Effects of Polyphenols

    African Journals Online (AJOL)

    Z. Ghouila, S. Laurent, S. Boutry, L. Vander Elst, F. Nateche, R. N. Muller, A. Baaliouamer

    2017-01-01

    Jan 1, 2017 ... At 100 μg/mL, GSE induced a moderate toxicity of the order of ... the many phytochemical compounds consumed in our diet, polyphenols are the most ... action of grape seed extract in many health related areas due to its antioxidant effect [11]. In ...... antibacterial activities of southern Serbian red wines.

  16. Antioxidative Polyphenols from Defatted Oilseed Cakes: Effect of Solvents

    Directory of Open Access Journals (Sweden)

    Sue-Siang Teh

    2014-02-01

    Full Text Available Defatted hemp, flax and canola seed cakes were extracted with different solvent systems namely methanol, ethanol, acetone, methanol 80%, acetone 80% and mixed solvent of methanol:acetone:water (MAW, 7:7:6, v/v/v. Each extract was analyzed for antioxidant capacity using ferric reducing/antioxidant power (FRAP and 2,2-diphenyl-1-picrylhydrazyl (DPPH radical scavenging assays. MAW exhibited the highest extraction of phenolic and flavonoid contents in the seed cakes, followed by acetone 80% and methanol 80%. The antioxidant capacity was proportional to the polyphenols recovery in the extracts. Canola seed cakes possessed the highest recovery of polyphenols and antioxidant capacity, followed by hemp and flax seed cakes. MAW extract of canola contained total phenolic content, 2104.67 ± 2.52 mg GAE/100 g fresh weight; total flavonoids, 37.79 ± 0.04 mg LUE/100 g fresh weight; percentage inhibition of DPPH•, 33.03 ± 0.38%; FRAP assay, 8.78 ± 0.07 μmol Fe (II/g fresh weight. Identification of individual polyphenol compounds were performed HPLC. MAW extract of canola had the highest (P < 0.05 concentration of all individual polyphenols except gallic acid and catechin. Highest concentration of quercetin and luteolin in MAW extract of hemp was obtained among all solvent systems.

  17. Polyphenols in foods are more complex than often thought.

    Science.gov (United States)

    Cheynier, Véronique

    2005-01-01

    Dietary polyphenols show a great diversity of structures, ranging from rather simple molecules (monomers and oligomers) to polymers. Higher-molecular-weight structures (with molecular weights of > 500) are usually designated as tannins, which refers to their ability to interact with proteins. Among them, condensed tannins (proanthocyanidins) are particularly important because of their wide distribution in plants and their contributions to major food qualities. All phenolic compounds are highly unstable and rapidly transformed into various reaction products when the plant cells are damaged (for instance, during food processing), thus adding to the complexity of dietary polyphenol composition. The polyphenol composition of plant-derived foods and beverages depends on that of the raw material used but also on the extraction process and subsequent biochemical and chemical reactions of plant polyphenols. The occurrence of specific tannin-like compounds (ie, thearubigins and theaflavins) arising from enzymatic oxidation is well documented in black tea. Various chemical reactions involving anthocyanins and/or flavanols have been demonstrated to occur during red wine aging. Current knowledge regarding the reaction mechanisms involved in some of these processes and the structures of the resulting products is reviewed. Their effects on organoleptic and nutritional quality are also discussed.

  18. Investigation of Argania spinosa L. (Skeels) polyphenols growing in ...

    African Journals Online (AJOL)

    Argania spinosa L. Skeels, belonging to the Argania genus of the Sapotaceae family, is a species native to Morocco and Algeria. Due to its perfect adaptation to soil and climate, this tree plays an important ecological role in a constantly threatened encroached desert region. To understand the biological role of polyphenols ...

  19. Hypertension, nitric oxide, oxidants, and dietary plant polyphenols.

    Science.gov (United States)

    Galleano, Monica; Pechanova, Olga; Fraga, Cesar G

    2010-12-01

    Fruits and vegetables are key foods whose high ingestion is associated with the improvement of numerous pathological conditions, including hypertension. Such health promoting actions have been increasingly ascribed to the antioxidant characteristics of different polyphenols in fruits and vegetables. Consequently, based on this assumption, many beverages and foods rich in polyphenols, grape, tea, cocoa, and soy products and many of their chemical constituents purified, are being studied both, as antioxidants and antihypertensive agents. This paper reviews the current evidence linking high polyphenol consumption with reductions in blood pressure. Basic chemical aspects of flavanols, flavonols, isoflavones and stilbenes, as possible responsible for the observed effects of those foods on blood pressure are included. Human interventions studies by using grapes and wine, cocoa and chocolate, black and green tea, soy products, and purified compounds ((+)-catequin, quercetin, (-)-epigallocatechin gallate) are summarized. The discussed hypothesis, strongly supported by experimental data in animals, is that by regulating nitric oxide bioavailability, polyphenols present in fruits and vegetables affect endothelial function and as a consequence, blood pressure. Even when data are not definitive and many questions remain open, the whole evidence is encouraging to start considering diets that can provide a benefit to hypertensive subjects, and those benefits will be more significant in people that do not have controlled his/her elevated blood pressure.

  20. rich extract on total polyphenols and antioxidant activity obtained

    African Journals Online (AJOL)

    Z. Ghouila

    USTHB, Organic Functional Analysis Laboratory, 16111 Bab Ezzouar, Algiers, ... Keywords: Ahmeur Bouamer, extraction, grape seeds, total polyphenols, ... These compounds are known as good natural antioxidant agents arising from natural ... surface between solid and liquid phases; this is mainly due to the dispersion of ...

  1. Psychiatric Disorders and Polyphenols: Can They Be Helpful in Therapy?

    Directory of Open Access Journals (Sweden)

    Jana Trebatická

    2015-01-01

    Full Text Available The prevalence of psychiatric disorders permanently increases. Polyphenolic compounds can be involved in modulation of mental health including brain plasticity, behaviour, mood, depression, and cognition. In addition to their antioxidant ability other biomodulating properties have been observed. In the pathogenesis of depression disturbance in neurotransmitters, increased inflammatory processes, defects in neurogenesis and synaptic plasticity, mitochondrial dysfunction, and redox imbalance are observed. Ginkgo biloba, green tea, and Quercus robur extracts and curcumin can affect neuronal system in depressive patients. ADHD patients treated with antipsychotic drugs, especially stimulants, report significant adverse effects; therefore, an alternative treatment is searched for. An extract from Ginkgo biloba and from Pinus pinaster bark, Pycnogenol, could become promising complementary supplements in ADHD treatment. Schizophrenia is a devastating mental disorder, with oxidative stress involved in its pathophysiology. The direct interference of polyphenols with schizophrenia pathophysiology has not been reported yet. However, increased oxidative stress caused by haloperidol was inhibited ex vivo by different polyphenols. Curcumin, extract from green tea and from Ginkgo biloba, may have benefits on serious side effects associated with administration of neuroleptics to patients suffering from schizophrenia. Polyphenols in the diet have the potential to become medicaments in the field of mental health after a thorough study of their mechanism of action.

  2. Selective methods for polyphenols and sulphur dioxide determination in wines.

    Science.gov (United States)

    García-Guzmán, Juan J; Hernández-Artiga, María P; Palacios-Ponce de León, Lourdes; Bellido-Milla, Dolores

    2015-09-01

    A critical review to the methods recommended by international bodies and widely used in the winery industry and research studies was performed. A Laccase biosensor was applied to the selective determination of polyphenols in wines. The biosensor response was characterised and it responds mainly to o-diphenols which are the principal polyphenols responsible for the stability and sensory qualities of wines. The spectrophotometric method to determine free and total sulphur dioxide recommended for beers was applied directly to wines. A sampling of 14 red and white wines was performed and they were analysed for biosensor polyphenol index (IBP) and sulphur dioxide concentration (SO2). The antioxidant capacity by the ABTS(+) spectrophotometric method was also determined. A correlation study was performed to elucidate the influence of the polyphenols and SO2 on the wines stability. High correlations were found between IBP and antioxidant capacity and low correlation between SO2 and antioxidant capacity. To evaluate the benefits of wine drinking a new parameter (IBP/SO2) is proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Antibacterial action of an aqueous grape seed polyphenolic extract ...

    African Journals Online (AJOL)

    The potential of a polyphenolic grape seed extract for use as a natural antibacterial agent was evaluated. Pure catechin (CS) and a previously LC-MS characterized grape seed phenolic extract (PE) were evaluated as antibacterial agents against Escherichia coli and Brevibacterium linens on solid and in liquid culture media ...

  4. Antioxidant, antibacterial and cell toxicity effects of polyphenols ...

    African Journals Online (AJOL)

    In this work and for the first time, significant concentrations of total polyphenols and flavonoids from Vitis vinifera L. grape seed extracts were obtained (256.15 ± 17.40 mg GAE/gdm and 14.08 ± 0.64 mg CE/gdm, respectively).The LC/MS analysis revealed richness in procyanidins. For antioxidant, antimicrobial and ...

  5. Polyphenolic acetates: A newer anti-Mycobacterial therapeutic option

    African Journals Online (AJOL)

    Anti acetyl lysine polyclonal antibody was purchased from Cell Signaling. ... acetyl group from various polyphenolic peracetate (PA) to certain receptor proteins such as cytochromes P-450, NADPH cytochrome reductase, nitric oxide synthase (NOS) has been established in various eukaryotic as well as prokaryotic sources.

  6. Antioxidant, antimicrobial and synergistic activities of tea polyphenols

    African Journals Online (AJOL)

    Microbial resistance to antibiotics has become an increasing global problem and there is a need to find out novel potent antimicrobial agents with alternative modes of action as accessories to antibiotic therapy. This study investigated the antioxidant, antimicrobial and synergistic properties of tea polyphenols. The tea ...

  7. Evaluation of Antioxidant and Antifungal Activities of Polyphenol-rich ...

    African Journals Online (AJOL)

    Purpose: To evaluate the antioxidant and antifungal activities of polyphenol-rich extracts of the dried fruit pulp of Garcinia pedunculata (GP) and Garcinia morella (GM) to determine their traditional claims of therapeutic activity against certain diseases. Methods: Analysis of total phenolic (TP) and flavonoid (TF) contents of the ...

  8. Cocoa and Dark Chocolate Polyphenols: From Biology to Clinical Applications

    Directory of Open Access Journals (Sweden)

    Thea Magrone

    2017-06-01

    Full Text Available It is well known that cocoa and dark chocolate possess polyphenols as major constituents whose dietary consumption has been associated to beneficial effects. In fact, cocoa and dark chocolate polyphenols exert antioxidant and anti-inflammatory activities switching on some important signaling pathways such as toll-like receptor 4/nuclear factor κB/signal transducer and activator of transcription. In particular, cocoa polyphenols induce release of nitric oxide (NO through activation of endothelial NO synthase which, in turn, accounts for vasodilation and cardioprotective effects. In the light of the above described properties, a number of clinical trials based on the consumption of cocoa and dark chocolate have been conducted in healthy subjects as well as in different categories of patients, such as those affected by cardiovascular, neurological, intestinal, and metabolic pathologies. Even if data are not always concordant, modifications of biomarkers of disease are frequently associated to improvement of clinical manifestations. Quite interestingly, following cocoa and dark chocolate ingestion, cocoa polyphenols also modulate intestinal microbiota, thus leading to the growth of bacteria that trigger a tolerogenic anti-inflammatory pathway in the host. Finally, many evidences encourage the consumption of cocoa and dark chocolate by aged people for the recovery of the neurovascular unit.

  9. Potential Effects of Pomegranate Polyphenols in Cancer Prevention and Therapy.

    Science.gov (United States)

    Turrini, Eleonora; Ferruzzi, Lorenzo; Fimognari, Carmela

    2015-01-01

    Cancer is the second leading cause of death and is becoming the leading one in old age. Vegetable and fruit consumption is inversely associated with cancer incidence and mortality. Currently, interest in a number of fruits high in polyphenols has been raised due to their reported chemopreventive and/or chemotherapeutic potential. Pomegranate has been shown to exert anticancer activity, which is generally attributed to its high content of polyphenols. This review provides a comprehensive analysis of known targets and mechanisms along with a critical evaluation of pomegranate polyphenols as future anticancer agents. Pomegranate evokes antiproliferative, anti-invasive, and antimetastatic effects, induces apoptosis through the modulation of Bcl-2 proteins, upregulates p21 and p27, and downregulates cyclin-cdk network. Furthermore, pomegranate blocks the activation of inflammatory pathways including, but not limited to, the NF-κB pathway. The strongest evidence for its anticancer activity comes from studies on prostate cancer. Accordingly, some exploratory clinical studies investigating pomegranate found a trend of efficacy in increasing prostate-specific antigen doubling time in patients with prostate cancer. However, the genotoxicity reported for pomegranate raised certain concerns over its safety and an accurate assessment of the risk/benefit should be performed before suggesting the use of pomegranate or its polyphenols for cancer-related therapeutic purposes.

  10. Cocoa and Dark Chocolate Polyphenols: From Biology to Clinical Applications

    Science.gov (United States)

    Magrone, Thea; Russo, Matteo Antonio; Jirillo, Emilio

    2017-01-01

    It is well known that cocoa and dark chocolate possess polyphenols as major constituents whose dietary consumption has been associated to beneficial effects. In fact, cocoa and dark chocolate polyphenols exert antioxidant and anti-inflammatory activities switching on some important signaling pathways such as toll-like receptor 4/nuclear factor κB/signal transducer and activator of transcription. In particular, cocoa polyphenols induce release of nitric oxide (NO) through activation of endothelial NO synthase which, in turn, accounts for vasodilation and cardioprotective effects. In the light of the above described properties, a number of clinical trials based on the consumption of cocoa and dark chocolate have been conducted in healthy subjects as well as in different categories of patients, such as those affected by cardiovascular, neurological, intestinal, and metabolic pathologies. Even if data are not always concordant, modifications of biomarkers of disease are frequently associated to improvement of clinical manifestations. Quite interestingly, following cocoa and dark chocolate ingestion, cocoa polyphenols also modulate intestinal microbiota, thus leading to the growth of bacteria that trigger a tolerogenic anti-inflammatory pathway in the host. Finally, many evidences encourage the consumption of cocoa and dark chocolate by aged people for the recovery of the neurovascular unit. PMID:28649251

  11. Mycobacterium intracellulare Infection Mimicking Progression of Scleroderma

    DEFF Research Database (Denmark)

    Krabbe, Simon; Engelhart, Merete; Thybo, Sören

    2017-01-01

    This case report describes a patient with scleroderma who developed Mycobacterium intracellulare infection, which for more than a year mimicked worsening of her connective tissue disorder. The patient was diagnosed with scleroderma based on puffy fingers that developed into sclerodactyly, abnormal......, unfortunately with significant scarring. Immunodeficiency testing was unremarkable. In summary, an infection with Mycobacterium intracellulare was mistaken for an unusually severe progression of scleroderma....

  12. Modulation of NADPH oxidase activity by known uraemic retention solutes.

    Science.gov (United States)

    Schulz, Anna Marta; Terne, Cindy; Jankowski, Vera; Cohen, Gerald; Schaefer, Mandy; Boehringer, Falko; Tepel, Martin; Kunkel, Desiree; Zidek, Walter; Jankowski, Joachim

    2014-08-01

    Uraemia and cardiovascular disease appear to be associated with an increased oxidative burden. One of the key players in the genesis of reactive oxygen species (ROS) is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Based on initial experiments demonstrating a decreased inhibitory effect on NADPH oxidase activity in the presence of plasma from patients with CKD-5D after dialysis compared with before dialysis, we investigated the effect of 48 known and commercially available uraemic retention solutes on the enzymatic activity of NADPH oxidase. Mononuclear leucocytes isolated from buffy coats of healthy volunteers were isolated, lysed and incubated with NADH in the presence of plasma from healthy controls and patients with CKD-5D. Furthermore, the leucocytes were lysed and incubated in the presence of uraemic retention solute of interest and diphenyleneiodonium chloride (DPI), an inhibitor of NADPH oxidase. The effect on enzymatic activity of NADPH oxidase was quantified within an incubation time of 120 min. Thirty-nine of the 48 uraemic retention solutes tested had a significant decreasing effect on NADPH oxidase activity. Oxalate has been characterized as the strongest inhibitor of NADPH oxidase (90% of DPI inhibition). Surprisingly, none of the uraemic retention solutes we investigated was found to increase NADPH oxidase activity. Furthermore, plasma from patients with CKD-5D before dialysis caused significantly higher inhibitory effect on NADPH oxidase activity compared with plasma from healthy subjects. However, this effect was significantly decreased in plasma from patients with CKD-5D after dialysis. The results of this study show that uraemic retention solutes modulated the activity of the NADPH oxidase. The results of this study might be the basis for the development of inhibitors applicable as drug in the situation of increased oxidative stress. © 2014 Stichting European Society for Clinical Investigation Journal Foundation.

  13. Chitosan/dextran multilayer microcapsules for polyphenol co-delivery

    Energy Technology Data Exchange (ETDEWEB)

    Paini, Marco, E-mail: marco.paini@unige.it [Department of Civil, Chemical and Environmental Engineering, University of Genoa, via Opera Pia 15, 16145 Genoa (Italy); Research Center for Biologically Inspired Engineering in Vascular Medicine and Longevity (BELONG), Via Montallegro 1, 16145 Genoa (Italy); Aliakbarian, Bahar; Casazza, Alessandro A.; Perego, Patrizia [Department of Civil, Chemical and Environmental Engineering, University of Genoa, via Opera Pia 15, 16145 Genoa (Italy); Research Center for Biologically Inspired Engineering in Vascular Medicine and Longevity (BELONG), Via Montallegro 1, 16145 Genoa (Italy); Ruggiero, Carmelina; Pastorino, Laura [Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genoa, Via Opera Pia 13, 16145 Genoa (Italy)

    2015-01-01

    Polysaccharide-based nanostructured polymeric microcapsules were fabricated by the electrostatic layer-by-layer self-assembly technique and used to encapsulate mixtures of four different polyphenols in order to achieve their controlled release. The real-time fabrication of the dextran/chitosan multilayer was monitored by quartz crystal microbalance with dissipation monitoring, and the morphology of the nanostructured polymeric capsules was characterized by scanning electron microscopy. The polyphenol encapsulation was obtained by reversible permeability variation of the capsule shell in ethanol:water mixtures. The loading efficiency in different water:ethanol mixtures and the release rate in acidic conditions were characterized by UV spectroscopy and HPLC. The higher loading efficiency was obtained with an ethanol:water 35:65 phenolic solution, equal to 42.0 ± 0.6%, with a total release of 11.5 ± 0.7 mg of total polyphenols per 11.3 μL of microcapsules after 240 min of incubation in acidic environment. The results suggest that polysaccharide-based capsules can be successfully used to encapsulate and release low water-soluble molecules, such as polyphenols. - Highlights: • Chitosan/dextran nanocapsules were made by layer-by-layer self-assembly technique. • Different ethanol:water mixtures of four polyphenols were encapsulated. • An encapsulation efficiency of 42.0 ± 0.6% was obtained using ethanol:water 35:65. • Release profiles in acidic environment were monitored by UV spectroscopy and HPLC. • Nanocapsules had shown a complete release after 60 min in acidic environment.

  14. Chitosan/dextran multilayer microcapsules for polyphenol co-delivery

    International Nuclear Information System (INIS)

    Paini, Marco; Aliakbarian, Bahar; Casazza, Alessandro A.; Perego, Patrizia; Ruggiero, Carmelina; Pastorino, Laura

    2015-01-01

    Polysaccharide-based nanostructured polymeric microcapsules were fabricated by the electrostatic layer-by-layer self-assembly technique and used to encapsulate mixtures of four different polyphenols in order to achieve their controlled release. The real-time fabrication of the dextran/chitosan multilayer was monitored by quartz crystal microbalance with dissipation monitoring, and the morphology of the nanostructured polymeric capsules was characterized by scanning electron microscopy. The polyphenol encapsulation was obtained by reversible permeability variation of the capsule shell in ethanol:water mixtures. The loading efficiency in different water:ethanol mixtures and the release rate in acidic conditions were characterized by UV spectroscopy and HPLC. The higher loading efficiency was obtained with an ethanol:water 35:65 phenolic solution, equal to 42.0 ± 0.6%, with a total release of 11.5 ± 0.7 mg of total polyphenols per 11.3 μL of microcapsules after 240 min of incubation in acidic environment. The results suggest that polysaccharide-based capsules can be successfully used to encapsulate and release low water-soluble molecules, such as polyphenols. - Highlights: • Chitosan/dextran nanocapsules were made by layer-by-layer self-assembly technique. • Different ethanol:water mixtures of four polyphenols were encapsulated. • An encapsulation efficiency of 42.0 ± 0.6% was obtained using ethanol:water 35:65. • Release profiles in acidic environment were monitored by UV spectroscopy and HPLC. • Nanocapsules had shown a complete release after 60 min in acidic environment

  15. Predictive relationship between polyphenol and nonfat cocoa solids content of chocolate.

    Science.gov (United States)

    Cooper, Karen A; Campos-Giménez, Esther; Jiménez Alvarez, Diego; Rytz, Andreas; Nagy, Kornél; Williamson, Gary

    2008-01-09

    Chocolate is often labeled with percent cocoa solids content. It is assumed that higher cocoa solids contents are indicative of higher polyphenol concentrations, which have potential health benefits. However, cocoa solids include polyphenol-free cocoa butter and polyphenol-rich nonfat cocoa solids (NFCS). In this study the strength of the relationship between NFCS content (estimated by theobromine as a proxy) and polyphenol content was tested in chocolate samples with labeled cocoa solids contents in the range of 20-100%, grouped as dark (n = 46), milk (n = 8), and those chocolates containing inclusions such as wafers or nuts (n = 15). The relationship was calculated with regard to both total polyphenol content and individual polyphenols. In dark chocolates, NFCS is linearly related to total polyphenols (r2 = 0.73). Total polyphenol content appears to be systematically slightly higher for milk chocolates than estimated by the dark chocolate model, whereas for chocolates containing other ingredients, the estimates fall close to or slightly below the model results. This shows that extra components such as milk, wafers, or nuts might influence the measurements of both theobromine and polyphenol contents. For each of the six main polyphenols (as well as their sum), the relationship with the estimated NFCS was much lower than for total polyphenols (r2 chocolate type, indicating that they might still have some predictive capabilities.

  16. Dietary Polyphenols, Mediterranean Diet, Prediabetes, and Type 2 Diabetes: A Narrative Review of the Evidence

    Directory of Open Access Journals (Sweden)

    Marta Guasch-Ferré

    2017-01-01

    Full Text Available Dietary polyphenols come mainly from plant-based foods including fruits, vegetables, whole grains, coffee, tea, and nuts. Polyphenols may influence glycemia and type 2 diabetes (T2D through different mechanisms, such as promoting the uptake of glucose in tissues, and therefore improving insulin sensitivity. This review aims to summarize the evidence from clinical trials and observational prospective studies linking dietary polyphenols to prediabetes and T2D, with a focus on polyphenol-rich foods characteristic of the Mediterranean diet. We aimed to describe the metabolic biomarkers related to polyphenol intake and genotype-polyphenol interactions modulating the effects on T2D. Intakes of polyphenols, especially flavan-3-ols, and their food sources have demonstrated beneficial effects on insulin resistance and other cardiometabolic risk factors. Several prospective studies have shown inverse associations between polyphenol intake and T2D. The Mediterranean diet and its key components, olive oil, nuts, and red wine, have been inversely associated with insulin resistance and T2D. To some extent, these associations may be attributed to the high amount of polyphenols and bioactive compounds in typical foods conforming this traditional dietary pattern. Few studies have suggested that genetic predisposition can modulate the relationship between polyphenols and T2D risk. In conclusion, the intake of polyphenols may be beneficial for both insulin resistance and T2D risk.

  17. Inducible bilirubin oxidase: A novel function for the mouse cytochrome P450 2A5

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Bakar, A' edah, E-mail: a.abubakar@uq.edu.au [The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 4072 Brisbane, Queensland (Australia); Arthur, Dionne Maioha [The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 4072 Brisbane, Queensland (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Adelaide (Australia); Aganovic, Simona [Department of Pharmaceutical Biosciences, Uppsala University, Biomedical Centre, Box 578, S-751 23 Uppsala (Sweden); Ng, Jack C. [The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 4072 Brisbane, Queensland (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Adelaide (Australia); Lang, Matti A. [The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 4072 Brisbane, Queensland (Australia); Department of Pharmaceutical Biosciences, Uppsala University, Biomedical Centre, Box 578, S-751 23 Uppsala (Sweden)

    2011-11-15

    We have previously shown that bilirubin (BR), a breakdown product of haem, is a strong inhibitor and a high affinity substrate of the mouse cytochrome P450 2A5 (CYP2A5). The antioxidant BR, which is cytotoxic at high concentrations, is potentially useful in cellular protection against oxygen radicals if its intracellular levels can be strictly controlled. The mechanisms that regulate cellular BR levels are still obscure. In this paper we provide preliminary evidence for a novel function of CYP2A5 as hepatic 'BR oxidase'. A high-performance liquid chromatography/electrospray ionisation mass spectrometry screening showed that recombinant yeast microsomes expressing the CYP2A5 oxidise BR to biliverdin, as the main metabolite, and to three other smaller products with m/z values of 301, 315 and 333. The metabolic profile is significantly different from that of chemical oxidation of BR. In chemical oxidation the smaller products were the main metabolites. This suggests that the enzymatic reaction is selective, towards biliverdin production. Bilirubin treatment of primary hepatocytes increased the CYP2A5 protein and activity levels with no effect on the corresponding mRNA. Co-treatment with cycloheximide (CHX), a protein synthesis inhibitor, resulted in increased half-life of the CYP2A5 compared to cells treated only with CHX. Collectively, the observations suggest that the CYP2A5 is potentially an inducible 'BR oxidase' where BR may accelerate its own metabolism through stabilization of the CYP2A5 protein. It is possible that this metabolic pathway is potentially part of the machinery controlling intracellular BR levels in transient oxidative stress situations, in which high amounts of BR are produced. -- Highlights: Black-Right-Pointing-Pointer CYP2A5 metabolizes bilirubin to biliverdin and dipyrroles. Black-Right-Pointing-Pointer Bilirubin increased the hepatic CYP2A5 protein and activity levels. Black-Right-Pointing-Pointer Bilirubin does not

  18. Tentative identification of polyphenols in Sempervivum tectorum and assessment of the antimicrobial activity of Sempervivum L.

    Science.gov (United States)

    Abram, V; Donko, M

    1999-02-01

    Polyphenols were isolated from sliced fresh leaves of Sempervivum tectorum. After 21 h of extraction by methanol and removal of chlorophyll, ethyl acetate was used to separate oligomeric and polymeric polyphenols: 0.07% of oligomeric and 0.13% of polymeric polyphenols were found. After acidic hydrolysis of the oligomeric polyphenols, it was established by TLC, HPLC, and FAB mass spectra that kaempferol was the unique aglycon of the three main oligomeric constituents of S. tectorum. Paper chromatography suggested delphinidol to be the only anthocyanidin detectable in the material obtained by acidic hydrolysis of the polymeric polyphenol fraction. After Haslam degradation of the same polymeric polyphenol fraction, only 4-thiobenzyl-(-)-epigallocatechin and 4-thiobenzyl-(-)-epigallocatechin-3-gallate were found and tentatively identified. We concluded that procyanidins of B2 type could be the major components of the polymeric polyphenol fraction of this plant. Antimicrobial activity of Sempervivum L. leaves against six of seven selected microorganisms was observed.

  19. Intracellular transport of cholesterol in mammalian cells

    International Nuclear Information System (INIS)

    Brasaemle, D.L.

    1989-01-01

    The erythrocyte was selected as a simple cell for the study of transbilayer movement of cholesterol. Cholesterol oxidase was used to measure the distribution of [ 3 H]cholesterol across the erythrocyte membrane. Cholesterol oxidase was also used to estimate the rate of transport of low density lipoprotein (LDL) cholesterol to the plasma membrane of cultured Chinese hamster ovary (CHO) fibroblasts; the half-time of this process was 42 minutes. The rate of transport of LDL cholesterol to the plasma membrane was confirmed by a second procedure using amphotericin B. Amphotericin B was also used to estimate the rate of transport of endogenously synthesized cholesterol to the plasma membrane of CHO cells. New methodology was developed including improvements of the previously published cholesterol oxidase assay for plasma membrane cholesterol. A new method for detecting transport of cholesterol to the plasma membrane in cultured cells was developed using amphotericin B. Preliminary studies investigated the use of fluorescent polyenes, pimaricin and etruscomycin, as probes for plasma membrane cholesterol in transport studies. Finally, a modification of a previously published cell staining protocol yielded a simple, quantitative assay for cell growth

  20. Curcuma longa polyphenols improve insulin-mediated lipid accumulation and attenuate proinflammatory response of 3T3-L1 adipose cells during oxidative stress through regulation of key adipokines and antioxidant enzymes.

    Science.gov (United States)

    Septembre-Malaterre, Axelle; Le Sage, Fanny; Hatia, Sarah; Catan, Aurélie; Janci, Laurent; Gonthier, Marie-Paule

    2016-07-08

    Plant polyphenols may exert beneficial action against obesity-related oxidative stress and inflammation which promote insulin resistance. This study evaluated the effect of polyphenols extracted from French Curcuma longa on 3T3-L1 adipose cells exposed to H2 O2 -mediated oxidative stress. We found that Curcuma longa extract exhibited high amounts of curcuminoids identified as curcumin, demethoxycurcumin, and bisdemethoxycurcumin, which exerted free radical-scavenging activities. Curcuma longa polyphenols improved insulin-mediated lipid accumulation and upregulated peroxisome proliferator-activated receptor-gamma gene expression and adiponectin secretion which decreased in H2 O2 -treated cells. Curcuminoids attenuated H2 O2 -enhanced production of pro-inflammatory molecules such as interleukin-6, tumor necrosis factor-alpha, monocyte chemoattractant protein-1, and nuclear factor κappa B. Moreover, they reduced intracellular levels of reactive oxygen species elevated by H2 O2 and modulated the expression of genes encoding superoxide dismutase and catalase antioxidant enzymes. Collectively, these findings highlight that Curcuma longa polyphenols protect adipose cells against oxidative stress and may improve obesity-related metabolic disorders. © 2016 BioFactors, 42(4):418-430, 2016. © 2016 International Union of Biochemistry and Molecular Biology.

  1. In Situ Enzymatically Generated Photoswitchable Oxidase Mimetics and Their Application for Colorimetric Detection of Glucose Oxidase.

    Science.gov (United States)

    Cao, Gen-Xia; Wu, Xiu-Ming; Dong, Yu-Ming; Li, Zai-Jun; Wang, Guang-Li

    2016-07-09

    In this study, a simple and amplified colorimetric assay is developed for the detection of the enzymatic activity of glucose oxidase (GOx) based on in situ formation of a photoswitchable oxidase mimetic of PO₄(3-)-capped CdS quantum dots (QDs). GOx catalyzes the oxidation of 1-thio-β-d-glucose to give 1-thio-β-d-gluconic acid which spontaneously hydrolyzes to β-d-gluconic acid and H₂S; the generated H₂S instantly reacts with Cd(2+) in the presence of Na₃PO₄ to give PO₄(3-)-stabilized CdS QDs in situ. Under visible-light (λ ≥ 400 nm) stimulation, the PO₄(3-)-capped CdS QDs are a new style of oxidase mimic derived by producing some active species, such as h⁺, (•)OH, O₂(•-) and a little H₂O₂, which can oxidize the typical substrate (3,3,5,5-tetramethylbenzydine (TMB)) with a color change. Based on the GOx-triggered growth of the oxidase mimetics of PO₄(3-)-capped CdS QDs in situ, we developed a simple and amplified colorimetric assay to probe the enzymatic activity of GOx. The proposed method allowed the detection of the enzymatic activity of GOx over the range from 25 μg/L to 50 mg/L with a low detection limit of 6.6 μg/L. We believe the PO₄(3-)-capped CdS QDs generated in situ with photo-stimulated enzyme-mimicking activity may find wide potential applications in biosensors.

  2. Neutrophils to the ROScue: Mechanisms of NADPH Oxidase Activation and Bacterial Resistance

    Directory of Open Access Journals (Sweden)

    Giang T. Nguyen

    2017-08-01

    Full Text Available Reactive oxygen species (ROS generated by NADPH oxidase play an important role in antimicrobial host defense and inflammation. Their deficiency in humans results in recurrent and severe bacterial infections, while their unregulated release leads to pathology from excessive inflammation. The release of high concentrations of ROS aids in clearance of invading bacteria. Localization of ROS release to phagosomes containing pathogens limits tissue damage. Host immune cells, like neutrophils, also known as PMNs, will release large amounts of ROS at the site of infection following the activation of surface receptors. The binding of ligands to G-protein-coupled receptors (GPCRs, toll-like receptors, and cytokine receptors can prime PMNs for a more robust response if additional signals are encountered. Meanwhile, activation of Fc and integrin directly induces high levels of ROS production. Additionally, GPCRs that bind to the bacterial-peptide analog fMLP, a neutrophil chemoattractant, can both prime cells and trigger low levels of ROS production. Engagement of these receptors initiates intracellular signaling pathways, resulting in activation of downstream effector proteins, assembly of the NADPH oxidase complex, and ultimately, the production of ROS by this complex. Within PMNs, ROS released by the NADPH oxidase complex can activate granular proteases and induce the formation of neutrophil extracellular traps (NETs. Additionally, ROS can cross the membranes of bacterial pathogens and damage their nucleic acids, proteins, and cell membranes. Consequently, in order to establish infections, bacterial pathogens employ various strategies to prevent restriction by PMN-derived ROS or downstream consequences of ROS production. Some pathogens are able to directly prevent the oxidative burst of phagocytes using secreted effector proteins or toxins that interfere with translocation of the NADPH oxidase complex or signaling pathways needed for its activation

  3. Visualization of monoamine oxidase in human brain

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, J.S.; Volkow, N.D.; Wang, G.J.; Pappas, N.; Shea, C.; MacGregor, R.R.; Logan, J.

    1996-12-31

    Monoamine oxidase is a flavin enzyme which exists in two subtypes, MAO A and MAO B. In human brain MAO B predominates and is largely compartmentalized in cell bodies of serotonergic neurons and glia. Regional distribution of MAO B was determined by positron computed tomography with volunteers after the administration of deuterium substituted [11C]L-deprenyl. The basal ganglia and thalamus exhibited the greatest concentrations of MAO B with intermediate levels in the frontal cortex and cingulate gyrus while lowest levels were observed in the parietal and temporal cortices and cerebellum. We observed that brain MAO B increases with are in health normal subjects, however the increases were generally smaller than those revealed with post-mortem studies.

  4. An ultrafiltration assay for lysyl oxidase

    International Nuclear Information System (INIS)

    Shackleton, D.R.; Hulmes, D.J.

    1990-01-01

    A modification of the original microdistillation assay for lysyl oxidase is described in which Amicon C-10 microconcentrators are used to separate, by ultrafiltration, the 3H-labeled products released from a [4,5-3H]-lysine-labeled elastin substrate. Enzyme activity is determined by scintillation counting of the ultrafiltrate, after subtraction of radioactivity released in the presence of beta-aminopropionitrile, a specific inhibitor of the enzyme. Conditions are described which optimize both the sensitivity and the efficient use of substrate. The assay shows linear inhibition of activity in up to 1 M urea; hence, as the enzyme is normally diluted in the assay, samples in 6 M urea can be assayed directly, without prior dialysis, and corrected for partial inhibition. Comparable results are obtained when enzyme activity is assayed by ultrafiltration or microdistillation. The assay is simple and convenient and, by using disposable containers throughout, it eliminates the need for time-consuming decontamination of radioactive glassware

  5. JNK and NADPH Oxidase Involved in Fluoride-Induced Oxidative Stress in BV-2 Microglia Cells

    Directory of Open Access Journals (Sweden)

    Ling Yan

    2013-01-01

    Full Text Available Excessive fluoride may cause central nervous system (CNS dysfunction, and oxidative stress is a recognized mode of action of fluoride toxicity. In CNS, activated microglial cells can release more reactive oxygen species (ROS, and NADPH oxidase (NOX is the major enzyme for the production of extracellular superoxide in microglia. ROS have been characterized as an important secondary messenger and modulator for various mammalian intracellular signaling pathways, including the MAPK pathways. In this study we examined ROS production and TNF-α, IL-1β inflammatory cytokines releasing, and the expression of MAPKs in BV-2 microglia cells treated with fluoride. We found that fluoride increased JNK phosphorylation level of BV-2 cells and pretreatment with JNK inhibitor SP600125 markedly reduced the levels of intracellular and NO. NOX inhibitor apocynin and iNOS inhibitor SMT dramatically decreased NaF-induced ROS and NO generations, respectively. Antioxidant melatonin (MEL resulted in a reduction in JNK phosphorylation in fluoride-stimulated BV-2 microglia. The results confirmed that NOX and iNOS played an important role in fluoride inducing oxidative stress and NO production and JNK took part in the oxidative stress induced by fluoride and meanwhile also could be activated by ROS in fluoride-treated BV-2 cells.

  6. JNK and NADPH Oxidase Involved in Fluoride-Induced Oxidative Stress in BV-2 Microglia Cells

    Science.gov (United States)

    Yan, Ling; Liu, Shengnan; Wang, Chen; Wang, Fei; Song, Yingli; Yan, Nan; Xi, Shuhua; Liu, Ziyou; Sun, Guifan

    2013-01-01

    Excessive fluoride may cause central nervous system (CNS) dysfunction, and oxidative stress is a recognized mode of action of fluoride toxicity. In CNS, activated microglial cells can release more reactive oxygen species (ROS), and NADPH oxidase (NOX) is the major enzyme for the production of extracellular superoxide in microglia. ROS have been characterized as an important secondary messenger and modulator for various mammalian intracellular signaling pathways, including the MAPK pathways. In this study we examined ROS production and TNF-α, IL-1β inflammatory cytokines releasing, and the expression of MAPKs in BV-2 microglia cells treated with fluoride. We found that fluoride increased JNK phosphorylation level of BV-2 cells and pretreatment with JNK inhibitor SP600125 markedly reduced the levels of intracellular O2 ·− and NO. NOX inhibitor apocynin and iNOS inhibitor SMT dramatically decreased NaF-induced ROS and NO generations, respectively. Antioxidant melatonin (MEL) resulted in a reduction in JNK phosphorylation in fluoride-stimulated BV-2 microglia. The results confirmed that NOX and iNOS played an important role in fluoride inducing oxidative stress and NO production and JNK took part in the oxidative stress induced by fluoride and meanwhile also could be activated by ROS in fluoride-treated BV-2 cells. PMID:24072958

  7. Evaluation of oxalate decarboxylase and oxalate oxidase for industrial applications.

    Science.gov (United States)

    Cassland, Pierre; Sjöde, Anders; Winestrand, Sandra; Jönsson, Leif J; Nilvebrant, Nils-Olof

    2010-05-01

    Increased recirculation of process water has given rise to problems with formation of calcium oxalate incrusts (scaling) in the pulp and paper industry and in forest biorefineries. The potential in using oxalate decarboxylase from Aspergillus niger for oxalic acid removal in industrial bleaching plant filtrates containing oxalic acid was examined and compared with barley oxalate oxidase. Ten different filtrates from chemical pulping were selected for the evaluation. Oxalate decarboxylase degraded oxalic acid faster than oxalate oxidase in eight of the filtrates, while oxalate oxidase performed better in one filtrate. One of the filtrates inhibited both enzymes. The potential inhibitory effect of selected compounds on the enzymatic activity was tested. Oxalate decarboxylase was more sensitive than oxalate oxidase to hydrogen peroxide. Oxalate decarboxylase was not as sensitive to chlorate and chlorite as oxalate oxidase. Up to 4 mM chlorate ions, the highest concentration tested, had no inhibitory effect on oxalate decarboxylase. Analysis of the filtrates suggests that high concentrations of chlorate present in some of the filtrates were responsible for the higher sensitivity of oxalate oxidase in these filtrates. Oxalate decarboxylase was thus a better choice than oxalate oxidase for treatment of filtrates from chlorine dioxide bleaching.

  8. Quantitation of immunoadsorbed flavoprotein oxidases by luminol-mediated chemiluminescence.

    Science.gov (United States)

    Hinkkanen, A; Maly, F E; Decker, K

    1983-04-01

    The detection of the flavoenzymes 6-hydroxy-L-nicotine oxidase and 6-hydroxy-D-nicotine oxidase at the sub-femtomol level was achieved by coupling the reaction of the immunoadsorbed proteins to the peroxidase-catalysed oxidation of luminol. The H2O2-producing oxidases retained their full activity when bound to the respective immobilized antibodies. This fact allowed the concentration of the enzymes from very dilute solutions and the quantitative assay of their activities in the microU range. Due to strict stereoselectivity and the absence of immunological cross-reactivity, the two flavoproteins could be determined in the same solution. This method was used to measure the 6-hydroxy-D-nicotine oxidase and 6-hydroxy-L-nicotine oxidase activities in Escherichia coli RR1 and different Arthrobacter strains cultured under non-inducing conditions. The same activity ratio of 6-hydroxy-L-nicotine oxidase/6-hydroxy-D-nicotine oxidase as in D L-nicotine-induced cells of A. oxidans was observed in non-induced wild type and in riboflavin-requiring (rf-) mutant cells of this aerob.

  9. Plant Polyphenolic Antioxidants in Management of Chronic Degenerative Diseases

    Directory of Open Access Journals (Sweden)

    R.K. Das

    2017-12-01

    Full Text Available With the over growing global population, degenerative diseases are on rise, despite using modern medicine for its cure. People prefer alternative systems of medicine like natural therapy and polyherbal therapy due to adverse effects of allopathic medication. According to W.H.O. report about 70% of world population relying on natural plant-based therapy. For a suitable, sustainable and cost effective cure use of polyphenolic natural antioxidants may be an appropriate tool. Now a day’s most food and pharmaceutical products contain synthetic antioxidants. But recent data indicating that, long term use of synthetic antioxidants could have carcinogenic effects on human cells. Thus, search for new natural and efficient antioxidants is need of the hour. Phenolic compounds (polyphenols are products of secondary metabolites and constitute one of the most widely distributed groups of substance in plant kingdom with more than 10,000 phenolic structures. Polyphenols are structurally characterized by the presence of one or more aromatic benzene ring compounds with one or more functional hydroxyl groups. Polyphenols are naturally occurring and most abundant antioxidants in human diets found largely in the fruits, vegetables and beverages. Plant flavonoids are the largest and best studied class of polyphenols which include more than 4000 compounds. Numerous studies confirm that, flavonoids exert a protective action on human health and are key components of a healthy and balanced diet. Epidemiological studies and associated meta-analysis correlate and strongly   suggest that, long term consumption of diets rich in plant flavonoids offer protection against development of chronic and degenerative diseases, such as cardiovascular diseases , diabetes , cancer, osteoporosis and neurodegenerative diseases. One of the main reasons for the age related diseases is linked with reduction in cellular oxidative stress. The involvement of reactive oxygen species (ROS in

  10. Platelet monoamine oxidase: specific activity and turnover number in headache

    International Nuclear Information System (INIS)

    Summers, K.M.; Brown, G.K.; Craig, I.W.; Peatfield, R.; Rose, F.C.

    1982-01-01

    Monoamine oxidase turnover numbers (molecules of substrate converted to product per minute per active site) have been calculated for the human platelet enzyme using [ 3 H]pargyline. Headache patients with high and low monoamine oxidase specific activities relative to controls were found to have turnover numbers very close to those for controls. This finding suggests that their specific activities vary because of differences in the concentration of active monoamine oxidase molecules, rather than differences in the ability of those enzyme molecules to catalyse the deamination reaction. (Auth.)

  11. Efficient intracellular delivery and improved biocompatibility of colloidal silver nanoparticles towards intracellular SERS immuno-sensing.

    Science.gov (United States)

    Bhardwaj, Vinay; Srinivasan, Supriya; McGoron, Anthony J

    2015-06-21

    High throughput intracellular delivery strategies, electroporation, passive and TATHA2 facilitated diffusion of colloidal silver nanoparticles (AgNPs) are investigated for cellular toxicity and uptake using state-of-art analytical techniques. The TATHA2 facilitated approach efficiently delivered high payload with no toxicity, pre-requisites for intracellular applications of plasmonic metal nanoparticles (PMNPs) in sensing and therapeutics.

  12. Ecklonia cava Polyphenol Has a Protective Effect against Ethanol-Induced Liver Injury in a Cyclic AMP-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Haruka Yamashita

    2015-06-01

    Full Text Available Previously, we showed that Ecklonia cava polyphenol (ECP treatment suppressed ethanol-induced increases in hepatocyte death by scavenging intracellular reactive oxygen species (ROS and maintaining intracellular glutathione levels. Here, we examined the effects of ECP on the activities of alcohol-metabolizing enzymes and their regulating mechanisms in ethanol-treated hepatocytes. Isolated hepatocytes were incubated with or without 100 mM ethanol. ECP was dissolved in dimethylsulfoxide. ECP was added to cultured cells that had been incubated with or without ethanol. The cells were incubated for 0–24 h. In cultured hepatocytes, the ECP treatment with ethanol inhibited cytochrome P450 2E1 (CYP2E1 expression and activity, which is related to the production of ROS when large quantities of ethanol are oxidized. On the other hand, ECP treatment with ethanol increased the activity of alcohol dehydrogenase (ADH and aldehyde dehydrogenase. These changes in activities of CYP2E1 and ADH were suppressed by treatment with H89, an inhibitor of protein kinase A. ECP treatment with ethanol enhanced cyclic AMP concentrations compared with those of control cells. ECP may be a candidate for preventing ethanol-induced liver injury via regulating alcohol metabolic enzymes in a cyclic AMP-dependent manner.

  13. Antioxidant activity of polyphenols from green and toasted mate tea.

    Science.gov (United States)

    Coentrão, Patricia de Abreu Marques; Teixeira, Valéria Laneuville; Netto, Annibal Duarte Pereira

    2011-05-01

    The production and distribution of toasted mate tea in Brazil has increased, which has resulted in its greater consumption. Mate tea is obtained by roasting non-fermented erva-mate in order to produce toasted erva-mate or toasted mate tea. However, although the product is much appreciated, studies of its chemical composition and the concentration of polyphenols, particularly flavonols present in toasted mate tea, are few and often controversial. This paper elucidates some misunderstandings involving the nomenclature of erva-mate and toasted mate, and mainly provides an overview of the composition of polyphenols and antioxidant capacity of toasted mate tea and its raw material, erva-mate, in comparison with other teas, the compositions of which were found in the literature.

  14. Inhibition of S-adenosylmethionine decarboxylase and diamine oxidase activities by analogues of methylglyoxal bis(guanylhydrazone) and their cellular uptake during lymphocyte activation.

    Science.gov (United States)

    Jänne, J; Morris, D R

    1984-03-15

    Several congeners of methylglyoxal bis(guanylhydrazone) were tested for their ability to inhibit eukaryotic putrescine-activated S-adenosylmethionine decarboxylase (EC 4.1.1.50) and intestinal diamine oxidase (EC 1.4.3.6). All the compounds tested, namely methylglyoxal bis(guanylhydrazone), ethylglyoxal bis(guanylhydrazone), dimethylglyoxal bis(guanylhydrazone) and the di-N"-methyl derivative of methylglyoxal bis(guanylhydrazone), were strong inhibitors of both yeast and mouse liver adenosylmethionine decarboxylase activity in vitro. The enzyme from both sources was most powerfully inhibited by ethylglyoxal bis(guanylhydrazone). All the diguanidines likewise inhibited diamine oxidase activity in vitro. The maximum intracellular concentrations of the ethyl and dimethylated analogues achieved in activated lymphocytes were only about one-fifth of that of the parent compound. However, both derivatives appeared to utilize the polyamine-carrier system, as indicated by competition experiments with spermidine.

  15. Investigating Internalization and Intracellular Trafficking of GPCRs

    DEFF Research Database (Denmark)

    Foster, Simon R; Bräuner-Osborne, Hans

    2017-01-01

    for signal transduction. One of the major mechanisms for GPCR regulation involves their endocytic trafficking, which serves to internalize the receptors from the plasma membrane and thereby attenuate G protein-dependent signaling. However, there is accumulating evidence to suggest that GPCRs can signal...... independently of G proteins, as well as from intracellular compartments including endosomes. It is in this context that receptor internalization and intracellular trafficking have attracted renewed interest within the GPCR field. In this chapter, we will review the current understanding and methodologies...

  16. Polyphenol Concentrate from Kazakhstan Cabernet Sauvignon Collection of Grapes

    OpenAIRE

    Zarina Shulgau; Vladislav Tritek; Alexander Gulyaev; Gulsim Adilgozhina; Talgat Nurgozhin

    2014-01-01

    Introduction. Nowadays, most of the research in the field of gerontology is focused on the effects of the grape polyphenols. In particular, resveratrol has been shown to increase life expectancy of various living organisms, including mammals. Resveratrol also plays an important role in cancer prevention and decreases the risk of developing cardiovascular disease. In our research, we proposed the development of the therapeutic product from Cabernet Sauvignon grapes that would exhibit the benef...

  17. Polyphenols distributions and reserve substances analysis in cacao somatic embryogenesis

    OpenAIRE

    Adriana María Gallego Rúa; Ana María Henao Ramírez; Aura Inés Urrea Trujillo; Lucía Atehortúa Garcés

    2016-01-01

    ABSTRACTIn order to understand the causes of lack of regeneration in cacao somatic embryos, two cacao varieties with different responses to regeneration potential were described based on their capacity to store different compounds. It is well known that seed reserves play a central role in the regenerative capability of somatic embryos; thus, we followed histochemical changes and reserve fluctuations of proteins, polysaccharides and polyphenols during somatic embryogenesis (SE) in the two cac...

  18. POLYPHENOLS DISTRIBUTION AND RESERVE SUBSTANCES ANALYSIS IN CACAO SOMATIC EMBRYOGENESIS

    OpenAIRE

    GALLEGO RÚA, Adriana María; HENAO RAMÍREZ, Ana María; URREA TRUJILLO, Aura Inés; ATEHORTÚA GARCÉS, Lucía

    2016-01-01

    In order to understand the causes of lack of regeneration in cacao somatic embryos, two cacao varieties with different responses to regeneration potential were described based on their capacity to store different compounds. It is well known that seed reserves play a central role in the regenerative capability of somatic embryos; thus, we followed histochemical changes and reserve fluctuations of proteins, polysaccharides and polyphenols during somatic embryogenesis (SE) in the two cacao varie...

  19. Benefits of Wine Polyphenols on Human Health: A Review

    Directory of Open Access Journals (Sweden)

    Roxana Banc

    2014-11-01

    Full Text Available This paper presents  an overview of the health benefits of wine polyphenols, induced by a moderate consumption. Several studies have shown that moderate wine intake may have many beneficial effects on human health and these effects are mainly attributed to the phenolic derivatives, especially flavonoids. Beside flavonoid compounds, phenolic acids (hydroxybenzoic acids and hydroxycinnamic acids and stilbenes are important non-flavonoid compounds present in grapes and wine. In the present review, the biological role of these classes of polyphenols in wine is briefly introduced, together with the knowledge on their bioavailability. The health-protective properties of wines are mainly due to antioxidant activities and capability to eliminate free radicals of the phenolic compounds. Additionally, these compounds (e.g. catechin and their oligomers and proanthocyanidins, quercetin, resveratrol have been reported to have multiple biological activities, including cardioprotective, anti-carcinogenic, anti-atherogenic, anti-inflammatory, antiviral and antibacterial properties. Epidemiological and clinical studies have pointed out that regular and moderate red wine consumption (one to two glasses a day is associated with decreased incidence of cardiovascular disease, hypertension, diabetes, and certain types of cancer, including lung, esophagus, stomach, colon, endometrium, ovarian and prostate cancer. The bioavailability of phenolic compounds differs largely among different polyphenol molecules, thus the most abundant polyphenols in wines are not necessarily those leading to the highest levels of active metabolites in target tissues. Therefore, since wine is a complex mixture, it is likely that a multitude of chemical constituents, as well as their metabolites, act synergistically on human health.

  20. Anticarcinogenic effects of polyphenolics from mango (Mangifera indica) varieties.

    Science.gov (United States)

    Noratto, Giuliana D; Bertoldi, Michele C; Krenek, Kimberley; Talcott, Stephen T; Stringheta, Paulo C; Mertens-Talcott, Susanne U

    2010-04-14

    Many polyphenolics contained in mango have shown anticancer activity. The objective of this study was to compare the anticancer properties of polyphenolic extracts from several mango varieties (Francis, Kent, Ataulfo, Tommy Atkins, and Haden) in cancer cell lines, including Molt-4 leukemia, A-549 lung, MDA-MB-231 breast, LnCap prostate, and SW-480 colon cancer cells and the noncancer colon cell line CCD-18Co. Cell lines were incubated with Ataulfo and Haden extracts, selected on the basis of their superior antioxidant capacity compared to the other varieties, where SW-480 and MOLT-4 were statistically equally most sensitive to both cultivars followed by MDA-MB-231, A-549, and LnCap in order of decreasing efficacy as determined by cell counting. The efficacy of extracts from all mango varieties in the inhibition of cell growth was tested in SW-480 colon carcinoma cells, where Ataulfo and Haden demonstrated superior efficacy, followed by Kent, Francis, and Tommy Atkins. At 5 mg of GAE/L, Ataulfo inhibited the growth of colon SW-480 cancer cells by approximately 72% while the growth of noncancer colonic myofibroblast CCD-18Co cells was not inhibited. The growth inhibition exerted by Ataulfo and Haden polyphenolics in SW-480 was associated with an increased mRNA expression of pro-apoptotic biomarkers and cell cycle regulators, cell cycle arrest, and a decrease in the generation of reactive oxygen species. Overall, polyphenolics from several mango varieties exerted anticancer effects, where compounds from Haden and Ataulfo mango varieties possessed superior chemopreventive activity.

  1. Effect of a heme oxygenase-1 inducer on NADPH oxidase ...

    African Journals Online (AJOL)

    Effect of a heme oxygenase-1 inducer on NADPH oxidase expression in ... and immunohistochemistry of hepatic NOX1 and NOX4 were investigated in week 4. ... (HO-1 inhibitor) administration caused upregulation of NOX gene expression ...

  2. Effects of glucose oxidase on the growth performance, serum ...

    African Journals Online (AJOL)

    Martina

    2016-02-06

    Feb 6, 2016 ... The experiment was conducted to investigate the effects of diets supplemented with ... Keywords: Glucose oxidase, intestinal health, performance, swine ..... This work was supported by the National High-Tech Research and ...

  3. Structure and activity of Aspergillus nidulans copper amine oxidase

    DEFF Research Database (Denmark)

    McGrath, Aaron P; Mithieux, Suzanne M; Collyer, Charles A

    2011-01-01

    Aspergillus nidulans amine oxidase (ANAO) has the unusual ability among the family of copper and trihydroxyphenylalanine quinone-containing amine oxidases of being able to oxidize the amine side chains of lysine residues in large peptides and proteins. We show here that in common with the related...... enzyme from the yeast Pichia pastoris, ANAO can promote the cross-linking of tropoelastin and oxidize the lysine residues in α-casein proteins and tropoelastin. The crystal structure of ANAO, the first for a fungal enzyme in this family, has been determined to a resolution of 2.4 Å. The enzyme is a dimer...... with the archetypal fold of a copper-containing amine oxidase. The active site is the most open of any of those of the structurally characterized enzymes in the family and provides a ready explanation for its lysine oxidase-like activity....

  4. Gene cloning and characterization of NADH oxidase from ...

    African Journals Online (AJOL)

    use

    2011-12-07

    Dec 7, 2011 ... potent inhibitors of NADH oxidases, silver nitrate and potassium cyanide did not show any significant ... anaerobes, a class of organisms that have not been ... DNA and amino acid sequence analyses were performed using.

  5. Effects of Polyphenols from Grape Seeds on Renal Lithiasis

    Directory of Open Access Journals (Sweden)

    Felix Grases

    2015-01-01

    Full Text Available Nephrolithiasis is a complex disease that results from a combination of factors related to both urine composition and kidney morphoanatomy. Development of calcium oxalate monohydrate papillary calculi is linked to initial subepithelial calcification of renal papilla. Progressive tissue calcification depends on preexisting injury and involves reactive oxygen species. Many plant extracts that protect against oxidative stress manifest antilithiasic activity. Our study focused on determining the effects of polyphenols on a lithiasis rat model. Rats were pretreated with polyphenols and grape seed extracts, followed by posterior induction of hyperoxalosis via treatment with ethylene glycol plus NH4Cl. The concentrations of calcium and other elements in kidney were determined, along with histological examination of kidney and 24 h urine analysis. Significant differences were observed in the renal calcium content between the control plus ethylene glycol-treated group and the epicatechin plus ethylene glycol-treated, red grape seed extract plus ethylene glycol-treated, and white grape seed extract plus ethylene glycol-treated groups, with reductions of about 50%. The antioxidant activity of polyphenols extracted from red and white grape seeds may be critical in the prevention of calcium oxalate monohydrate papillary calculus formation, particularly if calculi are induced by lesions caused by cytotoxic compounds with oxidative capacity.

  6. Utilization of tomato waste as a source of polyphenolic antioxidants

    Directory of Open Access Journals (Sweden)

    Savatović Slađana M.

    2010-01-01

    Full Text Available This study is concerned with the effects of two extraction procedures (using ultrasonic bath and high performance homogenizer on the extraction efficiency of polyphenolics present in the tomato waste. The isolation of flavonoid fraction of obtained extracts was performed by solid-phase extraction. The antioxidant activity of flavonoid fractions was determined using different spectrophotometric tests, including reducing power and 2,2- diphenyl-1-picrylhydrazyl (DPPH free radical scavenging assays. The content of total polyphenolics and flavonoids in extract obtained employing homogenizer (E2 was higher than in the extract obtained employing ultrasonic bath (E1, and it was 14.33 mg/g and 7.70 mg/g, respectively. The flavonoid fraction (EF2 of extract E2 showed higher antioxidant activity than flavonoid fraction (EF1 of extract E1. The DPPH free radical scavenging activity of fractions EF1 and EF2, expressed as EC50 value, were 0.78 mg/ml and 0.45 mg/ml, respectively. The obtained results show that tomato wastes can be used as an easily accessible source of antioxidant polyphenolics.

  7. Impact of canning and storage on apricot carotenoids and polyphenols.

    Science.gov (United States)

    Le Bourvellec, Carine; Gouble, Barbara; Bureau, Sylvie; Reling, Patrice; Bott, Romain; Ribas-Agusti, Albert; Audergon, Jean-Marc; Renard, Catherine M G C

    2018-02-01

    Apricot polyphenols and carotenoids were monitored after industrial and domestic cooking, and after 2months of storage for industrial processing. The main apricot polyphenols were flavan-3-ols, flavan-3-ol monomers and oligomers, with an average degree of polymerization between 4.7 and 10.7 and caffeoylquinic acids. Flavonols and anthocyanins were minor phenolic compounds. Upon processing procyanidins were retained in apricot tissue. Hydroxycinnamic acids, flavan-3-ol monomers, flavonols and anthocyanins leached in the syrup. Flavonol concentrations on per-can basis were significantly increased after processing. Industrial processing effects were higher than domestic cooking probably due to higher temperature and longer duration. After 2months of storage, among polyphenols only hydroxycinnamic acids, flavan-3-ol monomers and anthocyanins were reduced. Whichever the processing method, no significant reductions of total carotenoids were observed after processing. The cis-β-carotene isomer was significantly increased after processing but with a lower extent in domestic cooking. Significant decreased in total carotenoid compounds occurred during storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Antioxidant activity of polyphenol-enriched apple juice

    Directory of Open Access Journals (Sweden)

    Šumić Zdravko M.

    2009-01-01

    Full Text Available This paper shows that it is possible to improve antioxidant activity of apple juice by extraction of polyphenolic compounds from apple pomace, as waste, and their addition to the apple juice. Raw apple juice was prepared by pressing of apple mash. After thermal treatment of raw apple juice, depectinisation, additional clarification and filtration, the clarified juice was obtained. In raw and clarified apple juice soluble solids, acidity, reducing sugar, total sugars and brown component content were determined, as well as total dry matter, ash, acidity, reducing sugar, total sugars, total pectins, cellulose and starch content in apple mash and pomace. The total cotent of phenolics in clarified apple juice and apple pomace extract, determined spectrophotometrically using the Folin- Ciocalteu reagent, was 0.496 mg/ml and 6.505 mg/g, respectively. The antioxidant activity of clarified and polyphenol-enriched clarified juice (with addition of apple pomace extract in the concentrations 0.05 g, 0.1 g, 0.5 g and 1 g of phenolic compounds per liter of clarified apple juice was examined on stable 1,1-diphenyl-2-picrylhydrazyl (DPPH free radicals. Based on the obtained results it can be concluded that polyphenol-enriched clarified juice was more effective on DPPH radicals than the clarified apple juice.

  9. POLYPHENOLS IN CHOSEN SPECIES OF LEGUME - A REVIEW

    Directory of Open Access Journals (Sweden)

    Judita Bystrická

    2010-11-01

    Full Text Available  Legumes belongs to the most important grain for human consumption. They have been cultivated for thousands of years, and have played an important role in the traditional diets of many regions throughout the world. The most legumes are widely consumed in fresh and processed forms. The traditional way of legume preparation includes soaking in water following by cooking and are usually consumed boiled as soup, occasionally as roasted grains too. Legume are widely known for their nutraceutical value, but there is relatively little information about their polyphenols content (with the exception of soya. Inspite of the fact that phenolics in general are not the substances with nutritious value, the interest in them is still persisting for their positive effects on human health. For these reasons this short review is focused on summary of legume polyphenols – identification and quantification of phenolic acids, flavonoids and tannins in raw or processed legumes and their role in these crops. Monitoring and surveying of the changes of polyphenolic compounds contents thus complete knowledge about bioactive substances content in legumes species. And seeing that legumes are considered an ideal complement to cereals in diets, they gain increasing attention as functional food items. doi:10.5219/81

  10. Reactive oxygen species generation mediated by NADPH oxidase and PI3K/Akt pathways contribute to invasion of Streptococcus agalactiae in human endothelial cells.

    Science.gov (United States)

    Oliveira, Jessica Silva Santos de; Santos, Gabriela da Silva; Moraes, João Alfredo; Saliba, Alessandra Mattos; Barja-Fidalgo, Thereza Christina; Mattos-Guaraldi, Ana Luíza; Nagao, Prescilla Emy

    2018-01-01

    BACKGROUND Streptococcus agalactiae can causes sepsis, pneumonia, and meningitis in neonates, the elderly, and immunocompromised patients. Although the virulence properties of S. agalactiae have been partially elucidated, the molecular mechanisms related to reactive oxygen species (ROS) generation in infected human endothelial cells need further investigation. OBJECTIVES This study aimed to evaluate the influence of oxidative stress in human umbilical vein endothelial cells (HUVECs) during S. agalactiae infection. METHODS ROS production during S. agalactiae-HUVEC infection was detected using the probe CM-H2DCFDA. Microfilaments labelled with phalloidin-FITC and p47phox-Alexa 546 conjugated were analysed by immunofluorescence. mRNA levels of p47phox (NADPH oxidase subunit) were assessed using Real Time qRT-PCR. The adherence and intracellular viability of S. agalactiae in HUVECs with or without pre-treatment of DPI, apocynin (NADPH oxidase inhibitors), and LY294002 (PI3K inhibitor) were evaluated by penicillin/gentamicin exclusion. Phosphorylation of p47phox and Akt activation by S. agalactiae were evaluated by immunoblotting analysis. FINDINGS Data showed increased ROS production 15 min after HUVEC infection. Real-Time qRT-PCR and western blotting performed in HUVEC infected with S. agalactiae detected alterations in mRNA levels and activation of p47phox. Pre-treatment of endothelial cells with NADPH oxidase (DPI and apocynin) and PI3K/Akt pathway (LY294002) inhibitors reduced ROS production, bacterial intracellular viability, and generation of actin stress fibres in HUVECs infected with S. agalactiae. CONCLUSIONS ROS generation via the NADPH oxidase pathway contributes to invasion of S. agalactiae in human endothelial cells accompanied by cytoskeletal reorganisation through the PI3K/Akt pathway, which provides novel evidence for the involvement of oxidative stress in S. agalactiae pathogenesis.

  11. Production of rabbit antibodies against purified Glucose oxidase

    OpenAIRE

    Zia,Muhammad Anjum; Ain,Qurat-ul; Iftikhar,Tehreema; Abbas,Rao Zahid; Rahman,Khalil-ur

    2012-01-01

    Glucose oxidase is an active oxygen species generating enzyme produced from Aspergillus niger grown in submerged fermentation. Disintegration of the mycelium resulted in high glucose oxidase activity that was subjected to ammonium sulfate precipitation at 60-85% saturation rates that resulted to 6.14 U mg -1 specific activity. Purification of enzyme by anion exchange column (DEAE-Cellulose) resulted into 22.53 U mg-1 specific activity and 10.27 fold purification. This was applied to sephadex ...

  12. Suppressive effects of cacao polyphenols on the development of atherosclerosis in apolipoprotein E-deficient mice.

    Science.gov (United States)

    Natsume, Midori; Baba, Seigo

    2014-01-01

    Previous studies in humans have shown that the cacao polyphenols, (-)-epicatechin and its oligomers, prevent in vitro and ex vivo low-density lipoprotein oxidation mediated by free radical generators and metal ions and also reduce plasma LDL-cholesterol levels. The aim of this study was to examine the effects of cacao polyphenols on the development of atherosclerosis in apolipoprotein E-deficient (-/-) mice. Mice aged 8 weeks (n = 90) were randomized into three groups, and fed either normal mouse chow (controls) or chow supplemented with 0.25 or 0.40 % cacao polyphenols for 16 weeks. The mean plaque area in cross-sections of the brachiocephalic trunk was measured and found to be lower in the 0.25 % cacao polyphenol group than in the control group (p cacao polyphenol group (p cacao polyphenols inhibit the development of atherosclerosis in apolipoprotein E-deficient (-/-) mice by reducing oxidative stress and inflammatory responses.

  13. Activation of PAR-1/NADPH oxidase/ROS signaling pathways is crucial for the thrombin-induced sFlt-1 production in extravillous trophoblasts: possible involvement in the pathogenesis of preeclampsia.

    Science.gov (United States)

    Huang, Qi-Tao; Chen, Jian-Hong; Hang, Li-Lin; Liu, Shi-San; Zhong, Mei

    2015-01-01

    Preeclampsia was characterized by excessive thrombin generation in placentas and previous researches showed that thrombin could enhance soluble Fms-like tyrosine kinase 1 (sFlt-1) expression in first trimester trophoblasts. However, the detailed mechanism for the sFlt-1 over-production induced by thrombin was largely unknown. The purpose of this study was to explore the possible signaling pathway of thrombin-induced sFlt-1 production in extravillous trophoblasts (EVT). An EVT cell line (HRT-8/SVneo) was treated with various concentrations of thrombin. The mRNA expression and protein secretion of sFlt-1 in EVT were detected with real-time polymerase chain reaction and ELISA, respectively. The levels of intracellular reactive oxygen species (ROS) production were determined by DCFH-DA. Exposure of EVT to thrombin induced increased intracellular ROS generation and overexpression of sFlt-1 at both mRNA and protein levels in a dose dependent manner. Short interfering RNA (siRNA) directed against PAR-1 or apocynin (an inhibitor of NADPH oxidase) could decrease the intracellular ROS generation and subsequently suppressed the production of sFlt-1 at mRNA and protein levels. Our results suggested that thrombin increased sFlt-1 production in EVT via the PAR-1 /NADPH oxidase /ROS signaling pathway. This also highlights the PAR-1 / NADPH oxidase / ROS pathway might be a potential therapeutic target for the prevention of preeclampsia in the future. © 2015 S. Karger AG, Basel.

  14. Confirmation of a blocked amino terminus of sulfhydryl oxidase

    International Nuclear Information System (INIS)

    Janolino, V.G.; Morrison-Rowe, S.J.; Swaisgood, H.E.

    1990-01-01

    The isolation of sulfhydryl oxidase from bovine milk in a suitably pure form for sequencing was carried out by transient covalent affinity chromatography of diafiltered whey using cysteinylsuccinamidopropyl-glass as matrix. The glutathione-eluted proteins were separated by SDS-PAGE. By radiolabeling the affinity chromatography-purified enzyme with [ 14 C]iodoacetate before subjecting to SDS-PAGE, the sulfhydryl oxidase band was identified, because sulfhydryl oxidase is known to be inactivated by alkylation of one sulfhydryl group per mole. The results confirmed that sulfhydryl oxidase corresponds to the 85 (± 5)-kDa band observed on SDS-PAGE. The protein band corresponding to radiolabeled sulfhydryl oxidase was recovered from SDS-PAGE gels by electrophoretic elution and by electroblotting on polyvinylidene difluoride membrane and subjected to gas phase sequencing. Precautions were taken during electrophoretic elution to prevent reactions that result in N-terminal blocking. Both methods of protein recovery yielded negative results when subjected to sequence analysis indicating that the N-terminus of sulfhydryl oxidase is blocked

  15. Cationic polymers for intracellular delivery of proteins

    NARCIS (Netherlands)

    Coué, G.M.J.P.C.; Engbersen, Johannes F.J.; Samal, Sangram; Dubruel, Peter

    2015-01-01

    Many therapeutic proteins exert their pharmaceutical action inside the cytoplasm or onto individual organelles inside the cell. Intracellular protein delivery is considered to be the most direct, fastest and safest approach for curing gene-deficiency diseases, enhancing vaccination and triggering

  16. Molecular detection and characterization of sustainable intracellular ...

    African Journals Online (AJOL)

    3Centre for Biopolymer and Bio-Molecular Research, Athlone College of Technology, Republic of Ireland. ... cells was associated with the elongation of micro-villar extension that ... Keywords: Intracellular contaminants, cell cultures, bacteria culture, pre-clinical studies. ... production work involving culture technology.

  17. Spatial Cytoskeleton Organization Supports Targeted Intracellular Transport

    Science.gov (United States)

    Hafner, Anne E.; Rieger, Heiko

    2018-03-01

    The efficiency of intracellular cargo transport from specific source to target locations is strongly dependent upon molecular motor-assisted motion along the cytoskeleton. Radial transport along microtubules and lateral transport along the filaments of the actin cortex underneath the cell membrane are characteristic for cells with a centrosome. The interplay between the specific cytoskeleton organization and the motor performance realizes a spatially inhomogeneous intermittent search strategy. In order to analyze the efficiency of such intracellular search strategies we formulate a random velocity model with intermittent arrest states. We evaluate efficiency in terms of mean first passage times for three different, frequently encountered intracellular transport tasks: i) the narrow escape problem, which emerges during cargo transport to a synapse or other specific region of the cell membrane, ii) the reaction problem, which considers the binding time of two particles within the cell, and iii) the reaction-escape problem, which arises when cargo must be released at a synapse only after pairing with another particle. Our results indicate that cells are able to realize efficient search strategies for various intracellular transport tasks economically through a spatial cytoskeleton organization that involves only a narrow actin cortex rather than a cell body filled with randomly oriented actin filaments.

  18. Biological synthesis and characterization of intracellular gold ...

    Indian Academy of Sciences (India)

    In the present study, Aspergillus fumigatus was used for the intracellular synthesis of gold nanoparticles. Stable nanoparticles were produced when an aqueous solution of chloroauric acid (HAuCl4) was reduced by A. fumigatus biomass as the reducing agent. Production of nanoparticles was confirmed by the colour ...

  19. Optimizing Nanoelectrode Arrays for Scalable Intracellular Electrophysiology.

    Science.gov (United States)

    Abbott, Jeffrey; Ye, Tianyang; Ham, Donhee; Park, Hongkun

    2018-03-20

    Electrode technology for electrophysiology has a long history of innovation, with some decisive steps including the development of the voltage-clamp measurement technique by Hodgkin and Huxley in the 1940s and the invention of the patch clamp electrode by Neher and Sakmann in the 1970s. The high-precision intracellular recording enabled by the patch clamp electrode has since been a gold standard in studying the fundamental cellular processes underlying the electrical activities of neurons and other excitable cells. One logical next step would then be to parallelize these intracellular electrodes, since simultaneous intracellular recording from a large number of cells will benefit the study of complex neuronal networks and will increase the throughput of electrophysiological screening from basic neurobiology laboratories to the pharmaceutical industry. Patch clamp electrodes, however, are not built for parallelization; as for now, only ∼10 patch measurements in parallel are possible. It has long been envisioned that nanoscale electrodes may help meet this challenge. First, nanoscale electrodes were shown to enable intracellular access. Second, because their size scale is within the normal reach of the standard top-down fabrication, the nanoelectrodes can be scaled into a large array for parallelization. Third, such a nanoelectrode array can be monolithically integrated with complementary metal-oxide semiconductor (CMOS) electronics to facilitate the large array operation and the recording of the signals from a massive number of cells. These are some of the central ideas that have motivated the research activity into nanoelectrode electrophysiology, and these past years have seen fruitful developments. This Account aims to synthesize these findings so as to provide a useful reference. Summing up from the recent studies, we will first elucidate the morphology and associated electrical properties of the interface between a nanoelectrode and a cellular membrane

  20. Polyphenols in Cocoa and Cocoa Products: Is There a Link between Antioxidant Properties and Health?

    OpenAIRE

    Amin Ismail; Abbe Maleyki Mhd Jalil

    2008-01-01

    Cocoa and cocoa products have received much attention due to their significant polyphenol contents. Cocoa and cocoa products, namely cocoa liquor, cocoa powder and chocolates (milk and dark chocolates) may present varied polyphenol contents and possess different levels of antioxidant potentials. For the past ten years, at least 28 human studies have been conducted utilizing one of these cocoa products. However, questions arise on which of these products would deliver the best polyphenol conte...

  1. Antioxidant capacity and total polyphenol content in different apple varieties cultivated in Chile

    OpenAIRE

    Quitral, Vilma; Sepulveda, Marcela; Schwartz, Marco; Kern, Werther

    2014-01-01

    Three apple varieties cultivated in Chile were studied in total polyphenol content by Folin Ciocalteu method and antioxidant capacity by FRAP method: Granny Smith, Royal Gala and Fuji (whole and peeled apples). The total polyphenol content in whole and peeled apples do not show significant differences. The antioxidant capacity of the Granny Smith variety is significantly higher than Royal Gala and Fuji. Apple dehydration at 60 oC for 4 hours to obtain flakes keeps polyphenol content high. The...

  2. MONOAMINE OXIDASE: RADIOTRACER DEVELOPMENT AND HUMAN STUDIES.

    Energy Technology Data Exchange (ETDEWEB)

    FOWLER,J.S.; LOGAN,J.; VOLKOW,N.D.; WANG,G.J.; MACGREGOR,R.R.; DING,Y.S.

    2000-09-28

    PET is uniquely capable of providing information on biochemical transformations in the living human body. Although most of the studies of monoamine oxidase (MAO) have focused on measurements in the brain, the role of peripheral MAO as a phase 1 enzyme for the metabolism of drugs and xenobiotics is gaining attention (Strolin Benedetti and Tipton, 1998; Castagnoli et al., 1997.). MAO is well suited for this role because its concentration in organs such as kidneys, liver and digestive organs is high sometimes exceeding that in the brain. Knowledge of the distribution of the MAO subtypes within different organs and different cells is important in determining which substrates (and which drugs and xenobiotics) have access to which MAO subtypes. The highly variable subtype distribution with different species makes human studies even more important. In addition, the deleterious side effects of combining MAO inhibitors with other drugs and with foodstuffs makes it important to know the MAO inhibitory potency of different drugs both in the brain and in peripheral organs (Ulus et al., 2000). Clearly PET can play a role in answering these questions, in drug research and development and in discovering some of the factors which contribute to the highly variable MAO levels in different individuals.

  3. Epigallocatechin-3-gallate increases intracellular [Ca2+] in U87 cells mainly by influx of extracellular Ca2+ and partly by release of intracellular stores.

    Science.gov (United States)

    Kim, Hee Jung; Yum, Keun Sang; Sung, Jong-Ho; Rhie, Duck-Joo; Kim, Myung-Jun; Min, Do Sik; Hahn, Sang June; Kim, Myung-Suk; Jo, Yang-Hyeok; Yoon, Shin Hee

    2004-02-01

    Green tea has been receiving considerable attention as a possible preventive agent against cancer and cardiovascular disease. Epigallocatechin-3-gallate (EGCG) is a major polyphenol component of green tea. Using digital calcium imaging and an assay for [3H]-inositol phosphates, we determined whether EGCG increases intracellular [Ca2+] ([Ca2+]i) in non-excitable human astrocytoma U87 cells. EGCG induced concentration-dependent increases in [Ca2+]i. The EGCG-induced [Ca2+]i increases were reduced to 20.9% of control by removal of extracellular Ca2+. The increases were also inhibited markedly by treatment with the non-specific Ca2+ channel inhibitors cobalt (3 mM) for 3 min and lanthanum (1 mM) for 5 min. The increases were not significantly inhibited by treatment for 10 min with the L-type Ca2+ channel blocker nifedipine (100 nM). Treatment with the inhibitor of endoplasmic reticulum Ca2+-ATPase thapsigargin (1 micro M) also significantly inhibited the EGCG-induced [Ca2+]i increases. Treatment for 15 min with the phospholipase C (PLC) inhibitor neomycin (300 micro M) attenuated the increases significantly, while the tyrosine kinase inhibitor genistein (30 micro M) had no effect. EGCG increased [3H]-inositol phosphates formation via PLC activation. Treatment for 10 min with mefenamic acid (100 micro M) and flufenamic acid (100 micro M), derivatives of diphenylamine-2-carboxylate, blocked the EGCG-induced [Ca2+]i increase in non-treated and thapsigargin-treated cells but indomethacin (100 micro M) did not affect the increases. Collectively, these data suggest that EGCG increases [Ca2+]i in non-excitable U87 cells mainly by eliciting influx of extracellular Ca2+ and partly by mobilizing intracellular Ca2+ stores by PLC activation. The EGCG-induced [Ca2+]i influx is mediated mainly through channels sensitive to diphenylamine-2-carboxylate derivatives.

  4. Application of Pattern Recognition Method for Color Assessment of Oriental Tobacco based on HPLC of Polyphenols

    Directory of Open Access Journals (Sweden)

    Dagnon S

    2014-12-01

    Full Text Available The color of Oriental tobaccos was organoleptically assayed, and high performance liquid chromatography (HPLC of polyphenols was performed. The major tobacco polyphenols (chlorogenic acid, its isomers, and rutin, as well as scopoletin and kaempferol-3-rutinoside were quantified. HPLC polyphenol profiles were processed by pattern recognition method (PRM, and the values of indexes of similarity (Is,% between the cultivars studied were determined. It was shown that data from organoleptic color assessment and from PRM based on HPLC profiles of polyphenols of the cultivars studied are largely compatible. Hence, PRM can be suggested as an additional tool for objective color evaluation and classification of Oriental tobacco.

  5. Plant-Derived Polyphenols Interact with Staphylococcal Enterotoxin A and Inhibit Toxin Activity.

    Science.gov (United States)

    Shimamura, Yuko; Aoki, Natsumi; Sugiyama, Yuka; Tanaka, Takashi; Murata, Masatsune; Masuda, Shuichi

    2016-01-01

    This study was performed to investigate the inhibitory effects of 16 different plant-derived polyphenols on the toxicity of staphylococcal enterotoxin A (SEA). Plant-derived polyphenols were incubated with the cultured Staphylococcus aureus C-29 to investigate the effects of these samples on SEA produced from C-29 using Western blot analysis. Twelve polyphenols (0.1-0.5 mg/mL) inhibited the interaction between the anti-SEA antibody and SEA. We examined whether the polyphenols could directly interact with SEA after incubation of these test samples with SEA. As a result, 8 polyphenols (0.25 mg/mL) significantly decreased SEA protein levels. In addition, the polyphenols that interacted with SEA inactivated the toxin activity of splenocyte proliferation induced by SEA. Polyphenols that exerted inhibitory effects on SEA toxic activity had a tendency to interact with SEA. In particular, polyphenol compounds with 1 or 2 hexahydroxydiphenoyl groups and/or a galloyl group, such as eugeniin, castalagin, punicalagin, pedunculagin, corilagin and geraniin, strongly interacted with SEA and inhibited toxin activity at a low concentration. These polyphenols may be used to prevent S. aureus infection and staphylococcal food poisoning.

  6. Plant-Derived Polyphenols Interact with Staphylococcal Enterotoxin A and Inhibit Toxin Activity.

    Directory of Open Access Journals (Sweden)

    Yuko Shimamura

    Full Text Available This study was performed to investigate the inhibitory effects of 16 different plant-derived polyphenols on the toxicity of staphylococcal enterotoxin A (SEA. Plant-derived polyphenols were incubated with the cultured Staphylococcus aureus C-29 to investigate the effects of these samples on SEA produced from C-29 using Western blot analysis. Twelve polyphenols (0.1-0.5 mg/mL inhibited the interaction between the anti-SEA antibody and SEA. We examined whether the polyphenols could directly interact with SEA after incubation of these test samples with SEA. As a result, 8 polyphenols (0.25 mg/mL significantly decreased SEA protein levels. In addition, the polyphenols that interacted with SEA inactivated the toxin activity of splenocyte proliferation induced by SEA. Polyphenols that exerted inhibitory effects on SEA toxic activity had a tendency to interact with SEA. In particular, polyphenol compounds with 1 or 2 hexahydroxydiphenoyl groups and/or a galloyl group, such as eugeniin, castalagin, punicalagin, pedunculagin, corilagin and geraniin, strongly interacted with SEA and inhibited toxin activity at a low concentration. These polyphenols may be used to prevent S. aureus infection and staphylococcal food poisoning.

  7. Plant-Derived Polyphenols Interact with Staphylococcal Enterotoxin A and Inhibit Toxin Activity

    OpenAIRE

    Shimamura, Yuko; Aoki, Natsumi; Sugiyama, Yuka; Tanaka, Takashi; Murata, Masatsune; Masuda, Shuichi

    2016-01-01

    This study was performed to investigate the inhibitory effects of 16 different plant-derived polyphenols on the toxicity of staphylococcal enterotoxin A (SEA). Plant-derived polyphenols were incubated with the cultured Staphylococcus aureus C-29 to investigate the effects of these samples on SEA produced from C-29 using Western blot analysis. Twelve polyphenols (0.1-0.5 mg/mL) inhibited the interaction between the anti-SEA antibody and SEA. We examined whether the polyphenols could directly i...

  8. Pulse radiolysis studies of the interaction of tea polyphenol derivatives with oxidizing OH adduct of thymine

    International Nuclear Information System (INIS)

    Jiang Yue; Li Hucheng; Yao Side; Zuo Zhihua; Wang Zailan; Zhang Jiashan; Lin Nianyun

    1996-01-01

    The electron transfer reactions between oxidizing OH adduct of thymine with tea polyphenol derivatives has been investigated by pulse radiolysis. The tea polyphenol derivatives are identified as good antioxidants for reduction of oxidizing OH adducts of thymine. From buildup kinetic analysis of radical phenoxyl product, the rate constants for reactions of the N 3 radical with tea polyphenol derivatives have been determined to be (8-9) x 10 9 dm 3 /mol s, while the rate constants of electron transfer from tea polyphenol derivatives to oxidizing OH adducts of thymine was obtained to be around 10 9 dm 3 /mol s. Copyright direct C 1996 Elsevier Science Ltd

  9. Covalently bound phosphate residues in bovine milk xanthine oxidase and in glucose oxidase from Aspergillus niger: A reevaluation

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J.L.; Rajagopalan, K.V. (Duke Univ. Medical Center, Durham, NC (USA)); London, R.E. (National Institute of Environmental Health Science, Research Triangle Park, NC (USA))

    1989-09-01

    The reported presence of covalently bound phosphate residues in flavoproteins has significant implications with regard to the catalytic mechanisms and structural stability of the specific enzymes themselves and in terms of general cellular metabolic regulation. These considerations have led to a reevaluation of the presence of covalently bound phosphorus in the flavoproteins xanthine oxidase and glucose oxidase. Milk xanthine oxidase purified by a procedure that includes anion-exchange chromatography is shown to contain three phosphate residues. All three are noncovalently associated with the protein, two with the FAD cofactor, and one with the molybdenum cofactor. Results of chemical analysis and {sup 31}P NMR spectroscopy indicate that enzyme purified by this method contains no phosphoserine residues. Xanthine oxidase preparations purified by chromatography on calcium phosphate gel in place of DEAE-Sephadex yielded higher phosphate-to-protein ratios, which could be reduced to the expected values by additional purification on a folate affinity column. Highly active, highly purified preparations of glucose oxidase are shown to contain only the two phosphate residues of the FAD cofactor. The covalently bound bridging phosphate reported by others may arise in aged or degraded preparations of the enzyme but appears not to be a constituent of functional glucose oxidase. These results suggest that the presence of covalent phosphate residues in other flavoproteins should be rigorously reevaluated as well.

  10. Covalently bound phosphate residues in bovine milk xanthine oxidase and in glucose oxidase from Aspergillus niger: A reevaluation

    International Nuclear Information System (INIS)

    Johnson, J.L.; Rajagopalan, K.V.; London, R.E.

    1989-01-01

    The reported presence of covalently bound phosphate residues in flavoproteins has significant implications with regard to the catalytic mechanisms and structural stability of the specific enzymes themselves and in terms of general cellular metabolic regulation. These considerations have led to a reevaluation of the presence of covalently bound phosphorus in the flavoproteins xanthine oxidase and glucose oxidase. Milk xanthine oxidase purified by a procedure that includes anion-exchange chromatography is shown to contain three phosphate residues. All three are noncovalently associated with the protein, two with the FAD cofactor, and one with the molybdenum cofactor. Results of chemical analysis and 31 P NMR spectroscopy indicate that enzyme purified by this method contains no phosphoserine residues. Xanthine oxidase preparations purified by chromatography on calcium phosphate gel in place of DEAE-Sephadex yielded higher phosphate-to-protein ratios, which could be reduced to the expected values by additional purification on a folate affinity column. Highly active, highly purified preparations of glucose oxidase are shown to contain only the two phosphate residues of the FAD cofactor. The covalently bound bridging phosphate reported by others may arise in aged or degraded preparations of the enzyme but appears not to be a constituent of functional glucose oxidase. These results suggest that the presence of covalent phosphate residues in other flavoproteins should be rigorously reevaluated as well

  11. Cytochemical localization of catalase and several hydrogen peroxide-producing oxidases in the nucleoids and matrix of rat liver peroxisomes

    NARCIS (Netherlands)

    Veenhuis, M.; Wendelaar Bonga, S.E.

    1979-01-01

    The distribution of catalase, amino acid oxidase, α-hydroxy acid oxidase, urate oxidase and alcohol oxidase was studied cytochemically in rat hepatocytes. The presence of catalase was demonstrated with the conventional diaminobenzidine technique. Oxidase activities were visualized with methods based

  12. Serum diamine oxidase activity in patients with histamine intolerance.

    Science.gov (United States)

    Manzotti, G; Breda, D; Di Gioacchino, M; Burastero, S E

    2016-03-01

    Intolerance to various foods, excluding bona fide coeliac disease and lactose intolerance, represents a growing cause of patient visits to allergy clinics.Histamine intolerance is a long-known, multifaceted clinical condition triggered by histamine-rich foods and alcohol and/or by drugs that liberate histamine or block diamine oxidase (DAO), the main enzyme involved in the metabolism of ingested histamine. Histamine limitation diets impose complex, non-standardized restrictions that may severely impact the quality of life of patients. We retrospectively evaluated 14 patients who visited allergy outpatient facilities in northern Italy with a negative diagnosis for IgE-mediated food hypersensitivity, coeliac disease, conditions related to gastric hypersecretion, and systemic nickel hypersensitivity, and who previously underwent a histamine limitation diet with benefits for their main symptoms. Serum diamine oxidase levels and the clinical response to diamine oxidase supplementation were investigated. We found that 10 out of 14 patients had serum DAO activityintolerance. Moreover, 13 out of 14 patients subjectively reported a benefit in at least one of the disturbances related to food intolerances following diamine oxidase supplementation. The mean value (±SD) of diamine oxidase activity in the cohort of patients with histamine intolerance symptoms was 7.04±6.90 U/mL compared to 39.50±18.16 U/mL in 34 healthy controls (P=0.0031). In patients with symptoms triggered by histamine-rich food, measuring the serum diamine oxidase activity can help identify subjects who can benefit from a histamine limitation diet and/or diamine oxidase supplementation.Properly designed, controlled studies investigating histamine intolerance that include histamine provocation are indispensable for providing insights into the area of food intolerances, which are currently primarily managed with non-scientific approaches in Italy. © The Author(s) 2015.

  13. Monoamine Oxidase B Inhibitors in Parkinson's Disease.

    Science.gov (United States)

    Dezsi, Livia; Vecsei, Laszlo

    2017-01-01

    Parkinson's disease (PD) is a neurodegenerative disorder with a prevalence increasing with age. Oxidative stress and glutamate toxicity are involved in its pathomechanism. There are still many unmet needs of PD patients, including the alleviation of motor fluctuations and dyskinesias, and the development of therapies with neuroprotective potential. To give an overview of the pharmacological properties, the efficacy and safety of the monoamine oxidase B (MAO-B) inhibitors in the treatment of PD, with special focus on the results of randomized clinical trials. A literature search was conducted in PubMed for 'PD treatment', 'MAO-B inhibitors', 'selegiline', 'rasagiline', 'safinamide' and 'clinical trials' with 'MAO-B inhibitors' in 'Parkinson' disease'. MAO-B inhibitors have a favorable pharmacokinetic profile, improve the dopamine deficient state and may have neuroprotective properties. Safinamide exhibits an anti-glutamatergic effect as well. When applied as monotherapy, MAO-B inhibitors provide a modest, but significant improvement of motor function and delay the need for levodopa. Rasagiline and safinamide were proven safe and effective when added to a dopamine agonist in early PD. As add-on to levodopa, MAO-B inhibitors significantly reduced off-time and were comparable in efficacy to COMT inhibitors. Improvements were achieved as regards certain non-motor symptoms as well. Due to the efficacy shown in clinical trials and their favorable side-effect profile, MAO-B inhibitors are valuable drugs in the treatment of PD. They are recommended as monotherapy in the early stages of the disease and as add-on therapy to levodopa in advanced PD. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Monoamine oxidase and agitation in psychiatric patients.

    Science.gov (United States)

    Nikolac Perkovic, Matea; Svob Strac, Dubravka; Nedic Erjavec, Gordana; Uzun, Suzana; Podobnik, Josip; Kozumplik, Oliver; Vlatkovic, Suzana; Pivac, Nela

    2016-08-01

    Subjects with schizophrenia or conduct disorder display a lifelong pattern of antisocial, aggressive and violent behavior and agitation. Monoamine oxidase (MAO) is an enzyme involved in the degradation of various monoamine neurotransmitters and neuromodulators and therefore has a role in various psychiatric and neurodegenerative disorders and pathological behaviors. Platelet MAO-B activity has been associated with psychopathy- and aggression-related personality traits, while variants of the MAOA and MAOB genes have been associated with diverse clinical phenotypes, including aggressiveness, antisocial problems and violent delinquency. The aim of the study was to evaluate the association of platelet MAO-B activity, MAOB rs1799836 polymorphism and MAOA uVNTR polymorphism with severe agitation in 363 subjects with schizophrenia and conduct disorder. The results demonstrated significant association of severe agitation and smoking, but not diagnosis or age, with platelet MAO-B activity. Higher platelet MAO-B activity was found in subjects with severe agitation compared to non-agitated subjects. Platelet MAO-B activity was not associated with MAOB rs1799836 polymorphism. These results suggested the association between increased platelet MAO-B activity and severe agitation. No significant association was found between severe agitation and MAOA uVNTR or MAOB rs1799836 polymorphism, revealing that these individual polymorphisms in MAO genes are not related to severe agitation in subjects with schizophrenia and conduct disorder. As our study included 363 homogenous Caucasian male subjects, our data showing this negative genetic association will be a useful addition to future meta-analyses. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. [Effect of Kaixinsan on monoamine oxidase activity].

    Science.gov (United States)

    Wang, Shi; Dong, Xian-Zhe; Tan, Xiao; Wang, Yu-Ning; Liu, Ping

    2016-05-01

    To observe the effect of antidepressant medicine prescription, Kaixinsan (KXS) on monoamine oxidase (MAO) activity, and explore the mechanism of KXS in elevating the levels of monoamine neurotransmitter from the perspective of metabolism, in vitro enzyme reaction system and C6 neuroglial cells, the effect of KXS at different concentrations on MAO-A and MAO-B activity was observed. In animal studies, the effect of KXS at different concentrations on MAO-A and MAO-B activities of brain mitochondrialin normal rats and solitary chronic unpredictable moderate stress (CMS) model rats after intragastric administration for 1, 2, 3 weeks. Results showed that 10 g•L⁻¹ KXS could significantly reduce the activity of MAO-A and MAO-B in enzyme reaction system; and in C6 cells, KXS within 0.625-10 g•L⁻¹ concentration range had no significant effect on the activity of MAO-A, but had obvious inhibitory effect on the activity of MAO-B in a dose dependent manner. KXS had no significant effect on the activity of MAO-A and MAO-B in brains of normal rats after action for 1, 2, 3 weeks. After 2 and 3 weeks treatment with 338 mg•kg⁻¹ dose KXS, MAO-A activity in the brain of CMS rats was decreased as compared with the model group (PMAO-B activity after 1, 2, 3 weeks of treatment. The results indicated that KXS had certain effect on in vitro MAO-A and MAO-B activity, had no effect on brain MAO-A and MAO-B activity in vivo in normal rats, and had certain inhibitory effect on MAO-A activity in brains of CMS rats. Copyright© by the Chinese Pharmaceutical Association.

  16. Lysyl oxidase and adipose tissue dysfunction.

    Science.gov (United States)

    Pastel, Emilie; Price, Emily; Sjöholm, Kajsa; McCulloch, Laura J; Rittig, Nikolaj; Liversedge, Neil; Knight, Bridget; Møller, Niels; Svensson, Per-Arne; Kos, Katarina

    2018-01-01

    Lysyl oxidase (LOX) is an enzyme crucial for collagen fibre crosslinking and thus for fibrosis development. Fibrosis is characterised by a surplus of collagen fibre accumulation and is amongst others also a feature of obesity-associated dysfunctional adipose tissue (AT) which has been linked with type 2 diabetes. We hypothesised that in type 2 diabetes and obesity LOX expression and activity will be increased as a consequence of worsening AT dysfunction. This study aimed to provide a comprehensive characterisation of LOX in human AT. LOX mRNA expression was analysed in omental and abdominal subcutaneous AT obtained during elective surgery from subjects with a wide range of BMI, with and without diabetes. In addition, LOX expression was studied in subcutaneous AT before and 9.5months after bariatric surgery. To study the mechanism of LOX changes, its expression and activity were assessed after either hypoxia, recombinant human leptin or glucose treatment of AT explants. In addition, LOX response to acute inflammation was tested after stimulation by a single injection of lipopolysaccharide versus saline solution (control) in healthy men, in vivo. Quantity of mRNA was measured by RT-qPCR. LOX expression was higher in obesity and correlated with BMI whilst, in vitro, leptin at high concentrations, as a potential feedback mechanism, suppressed its expression. Neither diabetes status, nor hyperglycaemia affected LOX. Hypoxia and lipopolysaccharide-induced acute inflammation increased LOX AT expression, latter was independent of macrophage infiltration. Whilst LOX may not be affected by obesity-associated complications such as diabetes, our results confirm that LOX is increased by hypoxia and inflammation as underlying mechanism for its upregulation in adipose tissue with obesity. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Antiglycation, radical scavenging, and semicarbazide-sensitive amine oxidase inhibitory activities of acetohydroxamic acid in vitro

    Directory of Open Access Journals (Sweden)

    Liu YH

    2017-07-01

    Full Text Available Yuh-Hwa Liu,1,2,* Yeh-Lin Lu,3,* Der-Zen Liu,4 Wen-Chi Hou5 1Division of Gastroenterology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; 2Department of General Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; 3Department of Pharmacy, Taipei Medical University, Taipei, Taiwan; 4Graduate Institute of Biomedical Materials and Tissue Engineering, Taipei Medical University, Taipei, Taiwan; 5Graduate Institute of Pharmacognosy, Taipei Medical University, Taipei, Taiwan *These authors contributed equally to this work Abstract: Advanced glycation endproducts (AGEs can promote intracellular reactive oxygen species production, and the levels of AGEs are highly correlated with cardiovascular disease and diabetes complications. Acetohydroxamic acid (acetH is a bacterial urease inhibitor drug used to treat kidney stones and infections in the urinary tract, and hydroxyurea (HU is a drug used for antineoplasm and sickle cell diseases. Both acetH and HU are hydroxamic acid derivatives. It was found that acetH and HU at 2.5 or 5 mM showed anti-AGE formation by lowering the AGEs’ fluorescent intensities and Nε-(carboxymethyllysine formation in bovine serum albumin/galactose models, and both showed better and significant differences (P<0.05 compared to the positive control of aminoguanidine. Regarding radical scavenging activities, the half-inhibition concentrations (IC50 of acetH against α,α-diphenyl-β-picrylhydrazyl radical and hydroxyl radical were 34.86 and 104.42 µM, respectively. The IC50 of acetH against semicarbazide-sensitive amine oxidase was 10.56 µM, and acetH showed noncompetitive inhibition respective to the substrates (benzylamine. The antiglycation, antioxidant, and semicarbazide-sensitive amine oxidase inhibitory activities of acetH prove that it has the potential for treating cardiovascular disease and diabetes complications and it needs further investigation in animal models. Keywords: acetH, AGEs, Nε

  18. Antioxidant activity and nutrient release from polyphenol-enriched cheese in a simulated gastrointestinal environment.

    Science.gov (United States)

    Lamothe, Sophie; Langlois, Ariane; Bazinet, Laurent; Couillard, Charles; Britten, Michel

    2016-03-01

    Green tea polyphenols are recognized for their antioxidant properties and their effects on lipid digestion kinetics. Polyphenols are sensitive to degradation in the intestinal environment. Interactions with dairy proteins could modulate the stability and biological activity of polyphenols during digestion. The objective of this study was to evaluate the release of nutrients (polyphenols, fatty acids and peptides) and the antioxidant activity in polyphenol-enriched cheese containing different levels of calcium in a simulated gastrointestinal environment. The relationship between cheese matrix texture, matrix degradation and nutrient release during digestion was also studied. Green tea extract was added to milk at 0% or 0.1%, and cheeses were produced on a laboratory scale. The level of available calcium was adjusted to low (Ca(low)), regular (Ca(reg)) or high (Ca(high)) during the salting step of the cheese-making process. Cheeses were subjected to simulated digestion. The rate and extent of fatty acid release were 21% lower for Ca(low) cheese than for Ca(reg) and Ca(high) cheeses. The greater adhesiveness of Ca(low) cheese, which resulted in lower rates of matrix degradation and proteolysis, contributed to the reduced rate of lipolysis. The presence of green tea extract in cheese reduced the release of free fatty acids at the end of digestion by 7%. The addition of green tea extract increased cheese hardness but did not influence matrix degradation or proteolysis profiles. The formation of complexes between tea polyphenols and proteins within the cheese matrix resulted in a more than twofold increase in polyphenol recovery in the intestinal phase compared with the control (tea polyphenol extract incubated with polyphenol-free cheese). Antioxidant activity was 14% higher in the digest from polyphenol-enriched cheese than in the control. These results suggest that cheese is an effective matrix for the controlled release of nutrients and for the protection of green

  19. Dynamics of gradient formation by intracellular shuttling

    Energy Technology Data Exchange (ETDEWEB)

    Berezhkovskii, Alexander M. [Mathematical and Statistical Computing Laboratory, Division of Computational Bioscience, Center for Information Technology, National Institutes of Health, Bethesda, Maryland 20892 (United States); Shvartsman, Stanislav Y. [Department of Chemical and Biological Engineering and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544 (United States)

    2015-08-21

    A number of important cellular functions rely on the formation of intracellular protein concentration gradients. Experimental studies discovered a number of mechanisms for the formation of such gradients. One of the mechanisms relies on the intracellular shuttling of a protein that interconverts between the two states with different diffusivities, under the action of two enzymes, one of which is localized to the plasma membrane, whereas the second is uniformly distributed in the cytoplasm. Recent work reported an analytical solution for the steady state gradient in this mechanism, obtained in the framework of a one-dimensional reaction-diffusion model. Here, we study the dynamics in this model and derive analytical expressions for the Laplace transforms of the time-dependent concentration profiles in terms of elementary transcendental functions. Inverting these transforms numerically, one can obtain time-dependent concentration profiles of the two forms of the protein.

  20. Leishmania hijacking of the macrophage intracellular compartments.

    Science.gov (United States)

    Liévin-Le Moal, Vanessa; Loiseau, Philippe M

    2016-02-01

    Leishmania spp., transmitted to humans by the bite of the sandfly vector, are responsible for the three major forms of leishmaniasis, cutaneous, diffuse mucocutaneous and visceral. Leishmania spp. interact with membrane receptors of neutrophils and macrophages. In macrophages, the parasite is internalized within a parasitophorous vacuole and engages in a particular intracellular lifestyle in which the flagellated, motile Leishmania promastigote metacyclic form differentiates into non-motile, metacyclic amastigote form. This phenomenon is induced by Leishmania-triggered events leading to the fusion of the parasitophorous vacuole with vesicular members of the host cell endocytic pathway including recycling endosomes, late endosomes and the endoplasmic reticulum. Maturation of the parasitophorous vacuole leads to the intracellular proliferation of the Leishmania amastigote forms by acquisition of host cell nutrients while escaping host defense responses. © 2015 FEBS.

  1. Reduction of intracellular glutathione content and radiosensitivity

    International Nuclear Information System (INIS)

    Vos, O.; Schans, G.P. van der; Roos-Verheij, W.S.D.

    1986-05-01

    The intracellular glutathione (GSH) content in HeLa, CHO and V79 cells was reduced by incubating the cells in growth medium containing buthionine sulfoximine (BSO) or diethyl maleate (DEM). Clonogenicity, single strand DNA breaks (ssb) and double strand DNA breaks (dsb) were used as criteria for radiation induced damage after X- or γ irradiation. In survival experiments DEM gave a slightly larger sensitization although it gave a smaller reduction of the intracellular GSH. In general, sensitization was larger for dsb than for ssb, also the reduction of the OER was generally larger for dsb than for ssb. This may be due to the higher dose rate in case of dsb experiments resulting in a higher rate of radiochemical oxygen consumption. In general, no effect was found on post-irradiation repair of ssb and dsb. (Auth.)

  2. Reduction of intracellular glutathione content and radiosensitivity

    International Nuclear Information System (INIS)

    Vos, O.; Schans, G.P. van der; Roos-Verheij, W.S.D.

    1986-01-01

    The intracellular glutathione (GSH) content of HeLa, CHO and V79 cells was reduced by incubating the cells in growth medium containing buthionine sulphoximine or diethyl maleate (DEM). Clonogenicity, single-strand DNA breaks (ssb) and double-strand DNA breaks (dsb) were used as criteria for radiation-induced damage after X- or γ-irradiation. In survival experiments, DEM gave a slightly larger sensitization although it gave a smaller reduction of the intracellular GSH. In general, sensitization was larger for dsb than for ssb, also the reduction of the o.e.r. was generally larger for dsb than for ssb. This may be due to the higher dose rate in case of dsb experiments resulting in a higher rate of radiochemical oxygen consumption. In general, no effect was found on post-irradiation repair of ssb and dsb. (author)

  3. Intracellular mechanisms of solar water disinfection

    Science.gov (United States)

    Castro-Alférez, María; Polo-López, María Inmaculada; Fernández-Ibáñez, Pilar

    2016-12-01

    Solar water disinfection (SODIS) is a zero-cost intervention measure to disinfect drinking water in areas of poor access to improved water sources, used by more than 6 million people in the world. The bactericidal action of solar radiation in water has been widely proven, nevertheless the causes for this remain still unclear. Scientific literature points out that generation of reactive oxygen species (ROS) inside microorganisms promoted by solar light absorption is the main reason. For the first time, this work reports on the experimental measurement of accumulated intracellular ROS in E. coli during solar irradiation. For this experimental achievement, a modified protocol based on the fluorescent probe dichlorodihydrofluorescein diacetate (DCFH-DA), widely used for oxidative stress in eukaryotic cells, has been tested and validated for E. coli. Our results demonstrate that ROS and their accumulated oxidative damages at intracellular level are key in solar water disinfection.

  4. Plant-Derived Polyphenols in Human Health: Biological Activity, Metabolites and Putative Molecular Targets.

    Science.gov (United States)

    Olivares-Vicente, Marilo; Barrajon-Catalan, Enrique; Herranz-Lopez, Maria; Segura-Carretero, Antonio; Joven, Jorge; Encinar, Jose Antonio; Micol, Vicente

    2018-01-01

    Hibiscus sabdariffa, Lippia citriodora, Rosmarinus officinalis and Olea europaea, are rich in bioactive compounds that represent most of the phenolic compounds' families and have exhibited potential benefits in human health. These plants have been used in folk medicine for their potential therapeutic properties in human chronic diseases. Recent evidence leads to postulate that polyphenols may account for such effects. Nevertheless, the compounds or metabolites that are responsible for reaching the molecular targets are unknown. data based on studies directly using complex extracts on cellular models, without considering metabolic aspects, have limited applicability. In contrast, studies exploring the absorption process, metabolites in the blood circulation and tissues have become essential to identify the intracellular final effectors that are responsible for extracts bioactivity. Once the cellular metabolites are identified using high-resolution mass spectrometry, docking techniques suppose a unique tool for virtually screening a large number of compounds on selected targets in order to elucidate their potential mechanisms. we provide an updated overview of the in vitro and in vivo studies on the toxicity, absorption, permeability, pharmacokinetics and cellular metabolism of bioactive compounds derived from the abovementioned plants to identify the potential compounds that are responsible for the observed health effects. we propose the use of targeted metabolomics followed by in silico studies to virtually screen identified metabolites on selected protein targets, in combination with the use of the candidate metabolites in cellular models, as the methods of choice for elucidating the molecular mechanisms of these compounds. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  5. Natural polyphenols enhance stability of crosslinked UHMWPE for joint implants.

    Science.gov (United States)

    Shen, Jie; Gao, Guorong; Liu, Xincai; Fu, Jun

    2015-03-01

    Radiation-crosslinked UHMWPE has been used for joint implants since the 1990s. Postirradiation remelting enhances oxidative stability, but with some loss in strength and toughness. Vitamin E-stabilized crosslinked UHMWPE has shown improved strength and stability as compared with irradiated and remelted UHMWPE. With more active phenolic hydroxyl groups, natural polyphenols are widely used in the food and pharmaceutical industries as potent stabilizers and could be useful for oxidative stability in crosslinked UHMWPE. We asked whether UHMWPE blended with polyphenols would (1) show higher oxidation resistance after radiation crosslinking; (2) preserve the mechanical properties of UHMWPE after accelerated aging; and (3) alter the wear resistance of radiation-crosslinked UHMWPE. The polyphenols, gallic acid and dodecyl gallate, were blended with medical-grade UHMWPE followed by consolidation and electron beam irradiation at 100 kGy. Radiation-crosslinked virgin and vitamin E-blended UHMWPEs were used as reference materials. The UHMWPEs were aged at 120 °C in air with oxidation levels analyzed by infrared spectroscopy. Tensile (n = 5 per group) and impact (n = 3 per group) properties before and after aging as per ASTM F2003 were evaluated. The wear rates were examined by pin-on-disc testing (n = 3 per group). The data were reported as mean ± SDs. Statistical analysis was performed by using Student's t-test for a two-tailed distribution with unequal variance for tensile and impact data obtained with n ≥ 3. A significant difference is defined with p Accelerated aging of these polyphenol-blended UHMWPEs resulted in ultimate tensile strength of 50.4 ± 1.4 MPa and impact strength of 53 ± 5 kJ/m(2) for 100 kGy-irradiated UHMWPE with 0.05 wt% dodecyl gallate, for example, in comparison to 51.2 ± 0.7 MPa (p = 0.75) and 58 ± 5 kJ/m(2) (p = 0.29) before aging. The pin-on-disc wear rates of 100 kGy-irradiated UHMWPE with 0.05 wt% dodecyl gallate and 0.05 wt% gallic acid

  6. Intracellular serpins, firewalls and tissue necrosis.

    Science.gov (United States)

    Marciniak, Stefan J; Lomas, David A

    2008-02-01

    Luke and colleagues have recently attributed a new role to a member of the serpin superfamily of serine proteinase inhibitors. They have used Caenorhabditis elegans to show that an intracellular serpin is crucial for maintaining lysosomal integrity. We examine the role of this firewall in preventing necrosis and attempt to integrate this with current theories of stress-induced protein degradation. We discuss how mutant serpins cause disease either through polymerization or now, perhaps, by unleashing necrosis.

  7. Analysis of supercooling activity of tannin-related polyphenols.

    Science.gov (United States)

    Kuwabara, Chikako; Wang, Donghui; Endoh, Keita; Fukushi, Yukiharu; Arakawa, Keita; Fujikawa, Seizo

    2013-08-01

    Based on the discovery of novel supercooling-promoting hydrolyzable gallotannins from deep supercooling xylem parenchyma cells (XPCs) in Katsura tree (see Wang et al. (2012) [38]), supercooling capability of a wide variety of tannin-related polyphenols (TRPs) was examined in order to find more effective supercooling-promoting substances for their applications. The TRPs examined were single compounds including six kinds of hydrolyzable tannins, 11 kinds of catechin derivatives, two kinds of structural analogs of catechin and six kinds of phenolcarboxylic acid derivatives, 11 kinds of polyphenol mixtures and five kinds of crude plant tannin extracts. The effects of these TRPs on freezing were examined by droplet freezing assays using various solutions containing different kinds of identified ice nucleators such as the ice nucleation bacterium (INB) Erwinia ananas, the INB Xanthomonas campestris, silver iodide and phloroglucinol as well as a solution containing only unintentionally included unidentified airborne ice nucleators. Among the 41 kinds of TRPs examined, all of the hydrolyzable tannins, catechin derivatives, polyphenol mixtures and crude plant tannin extracts as well as a few structural analogs of catechin and phenolcarboxylic acid derivatives exhibited supercooling-promoting activity (SCA) with significant differences (p>0.05) from at least one of the solutions containing different kinds of ice nucleators. It should be noted that there were no TRPs exhibiting ice nucleation-enhancing activity (INA) in all solutions containing identified ice nucleators, whereas there were many TRPs exhibiting INA with significant differences in solutions containing unidentified ice nucleators alone. An emulsion freezing assay confirmed that these TRPs did not essentially affect homogeneous ice nucleation temperatures. It is thought that not only SCA but also INA in the TRPs are produced by interactions with heterogeneous ice nucleators, not by direct interaction with water

  8. Polyphenols from Bee Pollen: Structure, Absorption, Metabolism and Biological Activity

    Directory of Open Access Journals (Sweden)

    Anna Rzepecka-Stojko

    2015-12-01

    Full Text Available Bee pollen constitutes a natural source of antioxidants such as phenolic acids and flavonoids, which are responsible for its biological activity. Research has indicated the correlation between dietary polyphenols and cardioprotective, hepatoprotective, anti-inflammatory, antibacterial, anticancerogenic, immunostimulating, antianaemic effects, as well as their beneficial influence on osseous tissue. The beneficial effects of bee pollen on health result from the presence of phenolic acids and flavonoids which possess anti-inflammatory properties, phytosterol and linolenic acid which play an anticancerogenic role, and polysaccharides which stimulate immunological activity. Polyphenols are absorbed in the alimentary tract, metabolised by CYP450 enzymes, and excreted with urine and faeces. Flavonoids and phenolic acids are characterised by high antioxidative potential, which is closely related to their chemical structure. The high antioxidant potential of phenolic acids is due to the presence and location of hydroxyl groups, a carboxyl group in the immediate vicinity of ortho-diphenolic substituents, and the ethylene group between the phenyl ring and the carboxyl group. As regards flavonoids, essential structural elements are hydroxyl groups at the C5 and C7 positions in the A ring, and at the C3′ and C4′ positions in the B ring, and a hydroxyl group at the C3 position in the C ring. Furthermore, both, the double bond between C2 and C3, and a ketone group at the C4 position in the C ring enhance the antioxidative potential of these compounds. Polyphenols have an ideal chemical structure for scavenging free radicals and for creating chelates with metal ions, which makes them effective antioxidants in vivo.

  9. Fluorescent nanoparticles for intracellular sensing: A review

    International Nuclear Information System (INIS)

    Ruedas-Rama, Maria J.; Walters, Jamie D.; Orte, Angel; Hall, Elizabeth A.H.

    2012-01-01

    Highlights: ► Analytical applications of fluorescent nanoparticles (NPs) in intracellular sensing. ► Critical review on performance of QDots, metal NPs, silica NPs, and polymer NPs. ► Highlighted potential of fluorescence lifetime imaging microscopy (FLIM). - Abstract: Fluorescent nanoparticles (NPs), including semiconductor NPs (Quantum Dots), metal NPs, silica NPs, polymer NPs, etc., have been a major focus of research and development during the past decade. The fluorescent nanoparticles show unique chemical and optical properties, such as brighter fluorescence, higher photostability and higher biocompatibility, compared to classical fluorescent organic dyes. Moreover, the nanoparticles can also act as multivalent scaffolds for the realization of supramolecular assemblies, since their high surface to volume ratio allow distinct spatial domains to be functionalized, which can provide a versatile synthetic platform for the implementation of different sensing schemes. Their excellent properties make them one of the most useful tools that chemistry has supplied to biomedical research, enabling the intracellular monitoring of many different species for medical and biological purposes. In this review, we focus on the developments and analytical applications of fluorescent nanoparticles in chemical and biological sensing within the intracellular environment. The review also points out the great potential of fluorescent NPs for fluorescence lifetime imaging microscopy (FLIM). Finally, we also give an overview of the current methods for delivering of fluorescent NPs into cells, where critically examine the benefits and liabilities of each strategy.

  10. Fluorescent nanoparticles for intracellular sensing: A review

    Energy Technology Data Exchange (ETDEWEB)

    Ruedas-Rama, Maria J., E-mail: mjruedas@ugr.esmailto [Department of Physical Chemistry, Faculty of Pharmacy, University of Granada, Campus Cartuja, 18071, Granada (Spain); Walters, Jamie D. [Department of Chemical Engineering and Biotechnology, University of Cambridge, Tennis Court Road, Cambridge, UK CB2 1QT (United Kingdom); Orte, Angel [Department of Physical Chemistry, Faculty of Pharmacy, University of Granada, Campus Cartuja, 18071, Granada (Spain); Hall, Elizabeth A.H., E-mail: lisa.hall@biotech.cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QT (United Kingdom)

    2012-11-02

    Highlights: Black-Right-Pointing-Pointer Analytical applications of fluorescent nanoparticles (NPs) in intracellular sensing. Black-Right-Pointing-Pointer Critical review on performance of QDots, metal NPs, silica NPs, and polymer NPs. Black-Right-Pointing-Pointer Highlighted potential of fluorescence lifetime imaging microscopy (FLIM). - Abstract: Fluorescent nanoparticles (NPs), including semiconductor NPs (Quantum Dots), metal NPs, silica NPs, polymer NPs, etc., have been a major focus of research and development during the past decade. The fluorescent nanoparticles show unique chemical and optical properties, such as brighter fluorescence, higher photostability and higher biocompatibility, compared to classical fluorescent organic dyes. Moreover, the nanoparticles can also act as multivalent scaffolds for the realization of supramolecular assemblies, since their high surface to volume ratio allow distinct spatial domains to be functionalized, which can provide a versatile synthetic platform for the implementation of different sensing schemes. Their excellent properties make them one of the most useful tools that chemistry has supplied to biomedical research, enabling the intracellular monitoring of many different species for medical and biological purposes. In this review, we focus on the developments and analytical applications of fluorescent nanoparticles in chemical and biological sensing within the intracellular environment. The review also points out the great potential of fluorescent NPs for fluorescence lifetime imaging microscopy (FLIM). Finally, we also give an overview of the current methods for delivering of fluorescent NPs into cells, where critically examine the benefits and liabilities of each strategy.

  11. Intracellular Cholesterol Trafficking and Impact in Neurodegeneration

    Directory of Open Access Journals (Sweden)

    Fabian Arenas

    2017-11-01

    Full Text Available Cholesterol is a critical component of membrane bilayers where it plays key structural and functional roles by regulating the activity of diverse signaling platforms and pathways. Particularly enriched in brain, cholesterol homeostasis in this organ is singular with respect to other tissues and exhibits a heterogeneous regulation in distinct brain cell populations. Due to the key role of cholesterol in brain physiology and function, alterations in cholesterol homeostasis and levels have been linked to brain diseases and neurodegeneration. In the case of Alzheimer disease (AD, however, this association remains unclear with evidence indicating that either increased or decreased total brain cholesterol levels contribute to this major neurodegenerative disease. Here, rather than analyzing the role of total cholesterol levels in neurodegeneration, we focus on the contribution of intracellular cholesterol pools, particularly in endolysosomes and mitochondria through its trafficking via specialized membrane domains delineated by the contacts between endoplasmic reticulum and mitochondria, in the onset of prevalent neurodegenerative diseases such as AD, Parkinson disease, and Huntington disease as well as in lysosomal disorders like Niemann-Pick type C disease. We dissect molecular events associated with intracellular cholesterol accumulation, especially in mitochondria, an event that results in impaired mitochondrial antioxidant defense and function. A better understanding of the mechanisms involved in the distribution of cholesterol in intracellular compartments may shed light on the role of cholesterol homeostasis disruption in neurodegeneration and may pave the way for specific intervention opportunities.

  12. A bacteriophage endolysin that eliminates intracellular streptococci

    Science.gov (United States)

    Shen, Yang; Barros, Marilia; Vennemann, Tarek; Gallagher, D Travis; Yin, Yizhou; Linden, Sara B; Heselpoth, Ryan D; Spencer, Dennis J; Donovan, David M; Moult, John; Fischetti, Vincent A; Heinrich, Frank; Lösche, Mathias; Nelson, Daniel C

    2016-01-01

    PlyC, a bacteriophage-encoded endolysin, lyses Streptococcus pyogenes (Spy) on contact. Here, we demonstrate that PlyC is a potent agent for controlling intracellular Spy that often underlies refractory infections. We show that the PlyC holoenzyme, mediated by its PlyCB subunit, crosses epithelial cell membranes and clears intracellular Spy in a dose-dependent manner. Quantitative studies using model membranes establish that PlyCB interacts strongly with phosphatidylserine (PS), whereas its interaction with other lipids is weak, suggesting specificity for PS as its cellular receptor. Neutron reflection further substantiates that PlyC penetrates bilayers above a PS threshold concentration. Crystallography and docking studies identify key residues that mediate PlyCB–PS interactions, which are validated by site-directed mutagenesis. This is the first report that a native endolysin can traverse epithelial membranes, thus substantiating the potential of PlyC as an antimicrobial for Spy in the extracellular and intracellular milieu and as a scaffold for engineering other functionalities. DOI: http://dx.doi.org/10.7554/eLife.13152.001 PMID:26978792

  13. Production of rabbit antibodies against purified Glucose oxidase

    Directory of Open Access Journals (Sweden)

    Muhammad Anjum Zia

    2012-02-01

    Full Text Available Glucose oxidase is an active oxygen species generating enzyme produced from Aspergillus niger grown in submerged fermentation. Disintegration of the mycelium resulted in high glucose oxidase activity that was subjected to ammonium sulfate precipitation at 60-85% saturation rates that resulted to 6.14 U mg -1 specific activity. Purification of enzyme by anion exchange column (DEAE-Cellulose resulted into 22.53 U mg-1 specific activity and 10.27 fold purification. This was applied to sephadex G-200 column for gel filtration chromatography. It was observed that enzyme achieved 59.37 U mg-1of specific activity with 27.08 fold purity and 64.36% recovery. Purified glucose oxidase was injected into rabbits through intravenous route, to raise the glucose oxidase antibodies. After 30 days incubation period, the rabbits were slaughtered and serum was separated from blood. The antibodies were isolated by ammonium sulfate precipitation and confirmed by agar gel precipitation test. This could be a convenient and low cost alternate assay for the estimation of glucose oxidase in biological fluids. Moreover, such antibodies against the said enzyme could be used in various therapeutic and diagnostic applications.

  14. Calcium transport in vesicles energized by cytochrome oxidase

    Energy Technology Data Exchange (ETDEWEB)

    Rosier, Randy N. [Univ. of Rochester, NY (United States)

    1979-01-01

    Experiments on the reconstitution of cytochrome oxidase into phospholipid vesicles were carried out using techniques of selectivity energizing the suspensions with ascorbate and cytochrome c or ascorbate, PMS, and internally trapped cytochrome c. It was found that the K+ selective ionophore valinomycin stimulated the rate of respiration of cytochrome oxidase vesicles regardless of the direction of the K+ flux across the vesicle membranes. The stimulation occurred in the presence of protonophoric uncouplers and in the complete absence of potassium or in detergent-lysed suspensions. Gramicidin had similar effects and it was determined that the ionophores acted by specific interaction with cytochrome oxidase rather than by the previously assumed collapse of membrane potentials. When hydrophobic proteins and appropriate coupling factors were incorporated into the cytochrome oxidase, vesicles phosphorylation of ADP could be coupled to the oxidation reaction of cytochrome oxidase. Relatively low P:O, representing poor coupling of the system, were problematical and precluded measurements of protonmotive force. However the system was used to study ion translocation.

  15. Immobilization of xanthine oxidase on a polyaniline silicone support.

    Science.gov (United States)

    Nadruz, W; Marques, E T; Azevedo, W M; Lima-Filho, J L; Carvalho, L B

    1996-03-01

    A polyaniline silicone support to immobilize xanthine oxidase is proposed as a reactor coil to monitor the action of xanthine oxidase on hypoxanthine, xanthine and 6-mercaptopurine. A purified xanthine oxidase immobilized on this support lost 80% of the initial activity after 12 min of use. Co-immobilization of superoxide dismutase and catalase increased the stability of immobilized xanthine oxidase so that the derivative maintained 79% of its initial activity after 4.6 h of continuous use in which 1.5 mumol purine bases were converted by the immobilized enzyme system. There is no evidence of either polyaniline or protein leaching from the coil during 3 h of continuous use. When solutions (10 ml) of hypoxanthine, xanthine and 6-mercaptopurine were circulated individually through the xanthine oxidase-superoxide dismutase-catalase-polyaniline coil (1 mm internal diameter and 3 m in length, 3 ml internal volume) activities of 8.12, 11.17 and 1.09 nmol min-1 coil-1, respectively, were obtained. The advantages of the reactor configuration and the redox properties of the polymer, particularly with respect to immobilized oxidoreductases, make this methodology attractive for similar enzyme systems. This immobilized enzyme system using polyaniline-silicone as support converted 6-mercaptopurine to 6-thiouric acid with equal efficiency as resins based on polyacrylamide and polyamide 11.

  16. Pinus pinaster Knot: A Source of Polyphenols against Plasmopara viticola.

    Science.gov (United States)

    Gabaston, Julien; Richard, Tristan; Cluzet, Stéphanie; Palos Pinto, Antonio; Dufour, Marie-Cécile; Corio-Costet, Marie-France; Mérillon, Jean-Michel

    2017-10-11

    Pine knot extract from Pinus pinaster byproducts was characterized by UHPLC-DAD-MS and NMR. Fourteen polyphenols divided into four classes were identified as follows: lignans (nortrachelogenin, pinoresinol, matairesinol, isolariciresinol, secoisolariciresinol), flavonoids (pinocembrin, pinobanksin, dihydrokaempferol, taxifolin), stilbenes (pinosylvin, pinosylvin monomethyl ether, pterostilbene), and phenolic acids (caffeic acid, ferulic acid). The antifungal potential of pine knot extract, as well as the main compounds, was tested in vitro against Plasmopara viticola. The ethanolic extract showed a strong antimildew activity. In addition, pinosylvins and pinocembrin demonstrated significant inhibition of zoospore mobility and mildew development. These findings strongly suggest that pine knot is a potential biomass that could be used as a natural antifungal product.

  17. Novel value-added uses for sweet potato juice and flour in polyphenol- and protein-enriched functional food ingredients

    Science.gov (United States)

    Blackcurrant, blueberry, and muscadine grape juices were efficiently sorbed, concentrated, and stabilized into dry granular ingredient matrices which combined anti-inflammatory and antioxidant fruit polyphenols with sweet potato functional constituents (carotenoids, vitamins, polyphenols, fibers). T...

  18. Determination of biologically active phenols and polyphenols in various objects by chromatographic techniques

    International Nuclear Information System (INIS)

    Kochetova, M V; Semenistaya, E N; Larionov, Oleg G; Revina, A A

    2007-01-01

    Chromatographic techniques for determination of biologically active phenols and polyphenols are considered. Various methods for sample preparation and detection are compared. The advantages of high performance liquid chromatography with spectrophotometric detection for determination of antioxidants are demonstrated. Data on determination of biologically active phenols and polyphenols published in the period from 1995 to 2005 are analysed.

  19. Modulation of endogenous antioxidant system by wine polyphenols in human disease.

    Science.gov (United States)

    Rodrigo, Ramón; Miranda, Andrés; Vergara, Leonardo

    2011-02-20

    Numerous studies indicate that moderate red wine consumption is associated with a protective effect against all-cause mortality. Since oxidative stress constitutes a unifying mechanism of injury of many types of disease processes, it should be expected that polyphenolic antioxidants account for this beneficial effect. Nevertheless, beyond the well-known antioxidant properties of these compounds, they may exert several other protective mechanisms. Indeed, the overall protective effect of polyphenols is due to their large array of biological actions, such as free radical-scavenging, metal chelation, enzyme modulation, cell signalling pathways modulation and gene expression effects, among others. Wine possesses a variety of polyphenols, being resveratrol its most outstanding representative, due to its pleiotropic biological properties. The presence of ethanol in wine aids to polyphenol absorption, thereby contributing to their bioavailability. Before absorption, polyphenols must be hydrolyzed by intestinal enzymes or by colonic microflora. Then, they undergo intestinal and liver metabolism. There have been no reported polyphenol adverse effects derived from intakes currently associated with the normal diet. However, supplements for health-protection should be cautiously used as no level definition has been given to make sure the dose is safe. The role of oxidative stress and the beneficial effects of wine polyphenols against cardiovascular, cancer, diabetes, microbial, inflammatory, neurodegenerative and kidney diseases and ageing are reviewed. Future large scale randomized clinical trials should be conducted to fully establish the therapeutic use of each individual wine polyphenol against human disease. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Enzymatic biotransformation of polyphenolics increases antioxidant activity of red and white grape pomace

    Science.gov (United States)

    Grape pomace (GP) is a polyphenolic-rich byproduct of wine production. As most polyphenolics are either bound to cellular matrices or present as free polymeric forms, treatment with hydrolytic enzymes may act to increase GP functionalities. The aim of this study was to examine the impact of tannase ...

  1. Dietary polyphenol intake in Europe: the European Prospective Investigation into Cancer and Nutrition (EPIC) study

    NARCIS (Netherlands)

    Zamora-Ros, Raul; Knaze, Viktoria; Rothwell, Joseph A.; Hemon, Bertrand; Moskal, Aurelie; Overvad, Kim; Tjonneland, Anne; Kyro, Cecilie; Fagherazzi, Guy; Boutron-Ruault, Marie-Christine; Touillaud, Marina; Katzke, Verena; Kuehn, Tilman; Boeing, Heiner; Foerster, Jana; Trichopoulou, Antonia; Valanou, Elissavet; Peppa, Eleni; Palli, Domenico; Agnoli, Claudia; Ricceri, Fulvio; Tumino, Rosario; de Magistris, Maria Santucci; Peeters, Petra H. M.; Bueno-de-Mesquita, H. Bas; Engeset, Dagrun; Skeie, Guri; Hjartaker, Anette; Menendez, Virginia; Agudo, Antonio; Molina-Montes, Esther; Maria Huerta, Jose; Barricarte, Aurelio; Amiano, Pilar; Sonestedt, Emily; Nilsson, Lena Maria; Landberg, Rikard; Key, Timothy J.; Khaw, Kay-Thee; Wareham, Nicholas J.; Lu, Yunxia; Slimani, Nadia; Romieu, Isabelle; Riboli, Elio; Scalbert, Augustin

    Background/ObjectivesPolyphenols are plant secondary metabolites with a large variability in their chemical structure and dietary occurrence that have been associated with some protective effects against several chronic diseases. To date, limited data exist on intake of polyphenols in populations.

  2. Development of a Rapid and Simple Method to Remove Polyphenols from Plant Extracts

    Directory of Open Access Journals (Sweden)

    Imali Ranatunge

    2017-01-01

    Full Text Available Polyphenols are secondary metabolites of plants, which are responsible for prevention of many diseases. Polyvinylpolypyrrolidone (PVPP has a high affinity towards polyphenols. This method involves the use of PVPP column to remove polyphenols under centrifugal force. Standards of gallic acid, epigallocatechin gallate, vanillin, and tea extracts (Camellia sinensis were used in this study. PVPP powder was packed in a syringe with different quantities. The test samples were layered over the PVPP column and subjected to centrifugation. Supernatant was tested for the total phenol content. The presence of phenolic compounds and caffeine was screened by HPLC and measuring the absorbance at 280. The antioxidant capacity of standards and tea extracts was compared with the polyphenol removed fractions using DPPH scavenging assay. No polyphenols were found in polyphenolic standards or tea extracts after PVPP treatment. The method described in the present study to remove polyphenols is simple, inexpensive, rapid, and efficient and can be employed to investigate the contribution of polyphenols present in natural products to their biological activity.

  3. Polyphenol-aluminum complex formation: Implications for aluminum tolerance in plants

    Science.gov (United States)

    Natural polyphenols may play an important role in aluminum detoxification in some plants. We examined the interaction between Al3+ and the purified high molecular weight polyphenols pentagalloyl glucose (940 Da) and oenothein B (1568 Da), and the related compound methyl gallate (184 Da) at pH 4 and ...

  4. Polyphenol-Rich Pomegranate Juice Reduces IgE Binding to Cashew Nut Allergens

    Science.gov (United States)

    Cashew nut allergy is mediated by IgE binding to seed-storage proteins including Ana o 1, 2, and 3. Cashew nuts commonly cause severe reactions and only small amounts are needed. Polyphenol rich juices and polyphenol compounds have been demonstrated to complex with peanut allergens. The interacti...

  5. Characterization of tea polyphenols as potential environment-friendly fire retardants

    Science.gov (United States)

    Yao, Fengqi; Zhai, Chunjie; Wang, Haihui; Tao, Junjun

    2018-02-01

    In this work we investigated the oxidation properties of tea polyphenols and their potential as the fire retardants. Two types of tea polyphenols were adopted, which were extracted from red tea and green tea leaves, respectively. Their macroscopic performance during pyrolysis and oxidation at elevated temperatures were examined by using a heating furnace. Mass change, heat evolution and gas products of tea polyphenols during heating in air were also monitored by using a thermo-gravimetric analyzer (TGA) integrated with a differential scanning calorimeter (DSC) in conjunction with online Fourier Transform Infrared Spectroscopy (FTIR) and mass spectroscopy (MS). A tea polyphenol sample first becomes a brown semi-fluid after heating, and gradually turns into highly-porous black chars with significantly expanded volume. By raising the temperature to ∼550 °C at a rate of 10 °C/min, the mass of a sample reduces by nearly 70% to form a large quantity of inert gases that are mainly composed of H2O and CO2. It was found that the aerial oxidation products of tea polyphenols in the solid phase possess good heat insulation property; meanwhile, the substantial release of a lot of water and its evaporation during oxidation of tea polyphenols removes a large amount of heat from a sample located in a heating environment. The heat insulation of tea polyphenols may withstand up to 550 °C. The present work confirms tea polyphenols as potential superior and environment-friendly fire retardants.

  6. Polyphenol Bioaccessibility and Sugar Reducing Capacity of Black, Green, and White Teas

    Directory of Open Access Journals (Sweden)

    Shelly Coe

    2013-01-01

    Full Text Available Tea (Camellia sinensis is a widely consumed beverage and recognised for its potential enhancing effect on human health due to its rich polyphenol content. While a number of studies have investigated the quantity and type of polyphenols present in different tea samples, no study has reported the potential effect of digestive enzymes on the availability of tea polyphenols for human absorption or the subsequent impact on glycaemic response. The objectives of the present study were to assess the total polyphenol content of different teas, to assess the bioaccessibility of polyphenols in whole and bagged teas, and to determine the effect of black, white, and green tea infusions on sugar release. All of the teas were a significant source of polyphenols (10–116 mg Gallic acid equivalents/g. There was an overall increase in the release of polyphenols from both the bagged and the whole teas following in vitro digestion. Bagged green tea significantly ( reduced rapidly digestible starch from white bread samples compared to control and black and white bagged teas. The present study confirms that tea is a rich source of polyphenols and highlights the potential benefits it may have on modulating glycaemic response in humans.

  7. Effects of co-administration of dietary sodium arsenite and an NADPH oxidase inhibitor on the rat bladder epithelium

    International Nuclear Information System (INIS)

    Suzuki, Shugo; Arnold, Lora L.; Pennington, Karen L.; Kakiuchi-Kiyota, Satoko; Cohen, Samuel M.

    2009-01-01

    Arsenite (As III ), an inorganic arsenical, is a known human carcinogen, inducing tumors of the skin, urinary bladder and lung. It is metabolized to organic methylated arsenicals. Oxidative stress has been suggested as a mechanism for arsenic-induced carcinogenesis. Reactive oxygen species (ROS) can be important factors for carcinogenesis and tumor progression. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is known to produce intracellular ROS, therefore, we investigated the ability of apocynin (acetovanillone), an NADPH oxidase inhibitor, to inhibit the cytotoxicity and regenerative cell proliferation of arsenic in vitro and in vivo. Apocynin had similar effects in reducing the cytotoxicity of As III and dimethylarsinous acid (DMA III ) in rat urothelial cells in vitro. When tested at the same concentrations as apocynin, other antioxidants, such as L-ascorbate and N-acetylcysteine, did not inhibit As III -induced cytotoxicity but they were more effective at inhibiting DMA III -induced cytotoxicity compared with apocynin. In vivo, female rats were treated for 3 weeks with 100 ppm As III . Immunohistochemical staining for 8-hydroxy-2'-deoxyguanosine (8-OHdG) showed that apocynin reduced oxidative stress partially induced by As III treatment on rat urothelium, and significantly reduced the cytotoxicity of superficial cells detected by scanning electron microscopy (SEM). However, based on the incidence of simple hyperplasia and the bromodeoxyuridine (BrdU) labeling index, apocynin did not inhibit As III -induced urothelial cell proliferation. These data suggest that the NADPH oxidase inhibitor, apocynin, may have the ability to partially inhibit arsenic-induced oxidative stress and cytotoxicity of the rat bladder epithelium in vitro and in vivo. However, apocynin did not inhibit the regenerative cell proliferation induced by arsenite in a short-term study.

  8. Synthesis of cytochrome c oxidase 1 (SCO1) inhibits insulin sensitivity by decreasing copper levels in adipocytes.

    Science.gov (United States)

    Wei, Xiang-Bo; Guo, Liang; Liu, Yang; Zhou, Shui-Rong; Liu, Yuan; Dou, Xin; Du, Shao-Yue; Ding, Meng; Peng, Wan-Qiu; Qian, Shu-Wen; Huang, Hai-Yan; Tang, Qi-Qun

    2017-09-23

    Dysregulation of insulin signaling leads to type 2 diabetes mellitus (T2DM) and other metabolic disorders. Obesity is an important contributor to insulin resistance, and although the understanding of this relationship has improved in recent years, the mechanism of obesity-induced insulin resistance is not completely understood. Disorders of copper metabolism tend to accompany the development of obesity, which increases the risk of insulin resistance. Synthesis of cytochrome c oxidase 1 (SCO1) functions in the assembly of cytochrome c oxidase (COX) and cellular copper homeostasis. However, the role of SCO1 in the regulation of metabolism remains unknown. Here, we found that obese mice had higher expression of SCO1 and lower levels of copper in white adipose tissue (WAT) than did the control mice. Overexpression of SCO1 in adipocytes was associated with copper deficiency. Copper increased insulin sensitivity by decreasing the level of phosphatase and tensin homolog (PTEN) protein. Ectopic expression of SCO1 led to insulin resistance and was accompanied by a decrease in intracellular copper level, and addition of copper abolished the inhibitory effect of SCO1 on insulin sensitivity. Our results demonstrated a novel role of SCO1 in modulating insulin sensitivity via the regulation of copper concentration in WAT and suggested a potential therapeutic target for T2DM. Copyright © 2017. Published by Elsevier Inc.

  9. Nanometer size diesel exhaust particles are selectively toxic to dopaminergic neurons: the role of microglia, phagocytosis, and NADPH oxidase.

    Science.gov (United States)

    Block, M L; Wu, X; Pei, Z; Li, G; Wang, T; Qin, L; Wilson, B; Yang, J; Hong, J S; Veronesi, B

    2004-10-01

    The contributing role of environmental factors to the development of Parkinson's disease has become increasingly evident. We report that mesencephalic neuron-glia cultures treated with diesel exhaust particles (DEP; 0.22 microM) (5-50 microg/ml) resulted in a dose-dependent decrease in dopaminergic (DA) neurons, as determined by DA-uptake assay and tyrosine-hydroxylase immunocytochemistry (ICC). The selective toxicity of DEP for DA neurons was demonstrated by the lack of DEP effect on both GABA uptake and Neu-N immunoreactive cell number. The critical role of microglia was demonstrated by the failure of neuron-enriched cultures to exhibit DEP-induced DA neurotoxicity, where DEP-induced DA neuron death was reinstated with the addition of microglia to neuron-enriched cultures. OX-42 ICC staining of DEP treated neuron-glia cultures revealed changes in microglia morphology indicative of activation. Intracellular reactive oxygen species and superoxide were produced from enriched-microglia cultures in response to DEP. Neuron-glia cultures from NADPH oxidase deficient (PHOX-/-) mice were insensitive to DEP neurotoxicity when compared with control mice (PHOX+/+). Cytochalasin D inhibited DEP-induced superoxide production in enriched-microglia cultures, implying that DEP must be phagocytized by microglia to produce superoxide. Together, these in vitro data indicate that DEP selectively damages DA neurons through the phagocytic activation of microglial NADPH oxidase and consequent oxidative insult.

  10. Fluorescent Probes for Analysis and Imaging of Monoamine Oxidase Activity

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dokyoung; Jun, Yong Woong; Ahn, Kyo Han [POSTECH, Pohang (Korea, Republic of)

    2014-05-15

    Monoamine oxidases catalyze the oxidative deamination of dietary amines and amine neurotransmitters, and assist in maintaining the homeostasis of the amine neurotransmitters in the brain. Dysfunctions of these enzymes can cause neurological and behavioral disorders including Parkinson's and Alzheimer's diseases. To understand their physiological roles, efficient assay methods for monoamine oxidases are essential. Reviewed in this Perspective are the recent progress in the development of fluorescent probes for monoamine oxidases and their applications to enzyme assays in cells and tissues. It is evident that still there is strong need for a fluorescent probe with desirable substrate selectivity and photophysical properties to challenge the much unsolved issues associated with the enzymes and the diseases.

  11. Characterization of wheat germin (oxalate oxidase) expressed by Pichia pastoris

    International Nuclear Information System (INIS)

    Pan, Heng-Yen; Whittaker, Mei M.; Bouveret, Romaric; Berna, Anne; Bernier, Francois; Whittaker, James W.

    2007-01-01

    High-level secretory expression of wheat (Triticum aestivum) germin/oxalate oxidase was achieved in Pichia pastoris fermentation cultures as an α-mating factor signal peptide fusion, based on the native wheat cDNA coding sequence. The oxalate oxidase activity of the recombinant enzyme is substantially increased (7-fold) by treatment with sodium periodate, followed by ascorbate reduction. Using these methods, approximately 1 g (4 x 10 4 U) of purified, activated enzyme was obtained following eight days of induction of a high density Pichia fermentation culture, demonstrating suitability for large-scale production of oxalate oxidase for biotechnological applications. Characterization of the recombinant protein shows that it is glycosylated, with N-linked glycan attached at Asn47. For potential biomedical applications, a nonglycosylated (S49A) variant was also prepared which retains essentially full enzyme activity, but exhibits altered protein-protein interactions

  12. The use of galactose oxidase in lipid labeling

    International Nuclear Information System (INIS)

    Radin, N.S.; Evangelatos, G.P.

    1981-01-01

    Galactose oxidase can be used to oxidize the terminal carbon atom of lipids containing galactose or N-acetylgalactosamine, and the resultant aldehyde group can be reduced back to the original carbinol with radioactive borohydride. The efficiency of the first reaction has been investigated systematically by using [6- 3 H]galactosyl ceramide as substrate and measuring the amount of radioactive water formed. This enabled us to establish that the addition of catalase and peroxidase greatly speeded the oxidation, that phosphate and PIPES buffers were the best among those tested, that the reaction continued for 24 hr without a second addition of galactose oxidase, and that the optimum concentration of organic solvent (tetrahydrofuran) was 50%. The suggestion if made that a similar set of variables be studied for each lipid or nonlipid by the same basic technique: labeling by the oxidase/borohydride method and use of the resultant compound as substrate

  13. Zinc Oxide Nanoparticle Induces Microglial Death by NADPH-Oxidase-Independent Reactive Oxygen Species as well as Energy Depletion.

    Science.gov (United States)

    Sharma, Anuj Kumar; Singh, Vikas; Gera, Ruchi; Purohit, Mahaveer Prasad; Ghosh, Debabrata

    2017-10-01

    Zinc oxide nanoparticle (ZnO-NP) is one of the most widely used engineered nanoparticles. Upon exposure, nanoparticle can eventually reach the brain through various routes, interact with different brain cells, and alter their activity. Microglia is the fastest glial cell to respond to any toxic insult. Nanoparticle exposure can activate microglia and induce neuroinflammation. Simultaneous to activation, microglial death can exacerbate the scenario. Therefore, we focused on studying the effect of ZnO-NP on microglia and finding out the pathway involved in the microglial death. The present study showed that the 24 h inhibitory concentration 50 (IC 50 ) of ZnO-NP for microglia is 6.6 μg/ml. Early events following ZnO-NP exposure involved increase in intracellular calcium level as well as reactive oxygen species (ROS). Neither of NADPH oxidase inhibitors, apocynin, (APO) and diphenyleneiodonium chloride (DPIC) were able to reduce the ROS level and rescue microglia from ZnO-NP toxicity. In contrary, N-acetyl cysteine (NAC) showed opposite effect. Exogenous supplementation of superoxide dismutase (SOD) reduced ROS significantly even beyond control level but partially rescued microglial viability. Interestingly, pyruvate supplementation rescued microglia near to control level. Following 10 h of ZnO-NP exposure, intracellular ATP level was measured to be almost 50 % to the control. ZnO-NP-induced ROS as well as ATP depletion both disturbed mitochondrial membrane potential and subsequently triggered the apoptotic pathway. The level of apoptosis-inducing proteins was measured by western blot analysis and found to be upregulated. Taken together, we have deciphered that ZnO-NP induced microglial apoptosis by NADPH oxidase-independent ROS as well as ATP depletion.

  14. Ultrasound assisted extraction of polyphenols and their distribution in whole mung bean, hull and cotyledon.

    Science.gov (United States)

    Singh, Barinderjit; Singh, Narpinder; Thakur, Sheetal; Kaur, Amritpal

    2017-03-01

    In this study, extraction of polyphenols using different solvents (acetone, ethanol, methanol and water) with ultrasound and conventional method from whole mung bean (WMB), hull and cotyledon was conducted. Total phenolic content (TPC), total flavonoids content (TFC), total antioxidant activities (TAA), ferric reducing power (FRP) and DPPH radical scavenging activity were determined. Ultrasound treated extracts exhibited higher TPC, TFC, TAA, FRP and DPPH in different mung bean fractions than CSE. Among the solvents, acetone showed better TPC, TFC, TAA, FRP and DPPH. Hull had significantly higher TPC, TFC, TAA, FRP and DPPH than WMB and cotyledon. Sinapic acid (SA) was the major polyphenol in different fractions. Acetone extract of hull showed high polyphenol content. SA, ferulic acid, catechin, p-coumaric acid, resveratrol, quercetin and luteolin were the major contributors to antioxidant activity of acetone extract. Mung bean hull contained the maximum polyphenols and acetone was observed to be the best extraction medium for polyphenols in combination with ultrasound.

  15. Chemometric classification of apple juices according to variety and geographical origin based on polyphenolic profiles.

    Science.gov (United States)

    Guo, Jing; Yue, Tianli; Yuan, Yahong; Wang, Yutang

    2013-07-17

    To characterize and classify apple juices according to apple variety and geographical origin on the basis of their polyphenol composition, the polyphenolic profiles of 58 apple juice samples belonging to 5 apple varieties and from 6 regions in Shaanxi province of China were assessed. Fifty-one of the samples were from protected designation of origin (PDO) districts. Polyphenols were determined by high-performance liquid chromatography coupled to photodiode array detection (HPLC-PDA) and to a Q Exactive quadrupole-Orbitrap mass spectrometer. Chemometric techniques including principal component analysis (PCA) and stepwise linear discriminant analysis (SLDA) were carried out on polyphenolic profiles of the samples to develop discrimination models. SLDA achieved satisfactory discriminations of apple juices according to variety and geographical origin, providing respectively 98.3 and 91.2% success rate in terms of prediction ability. This result demonstrated that polyphenols could served as characteristic indices to verify the variety and geographical origin of apple juices.

  16. Proline oxidase silencing induces proline-dependent pro-survival pathways in MCF-7 cells

    Science.gov (United States)

    Zareba, Ilona; Celinska-Janowicz, Katarzyna; Surazynski, Arkadiusz; Miltyk, Wojciech; Palka, Jerzy

    2018-01-01

    Proline degradation by proline dehydrogenase/proline oxidase (PRODH/POX) contributes to apoptosis or autophagy. The identification of specific pathway of apoptosis/survival regulation is the aim of this study. We generated knocked-down PRODH/POX MCF-7 breast cancer cells (MCF-7shPRODH/POX). PRODH/POX silencing did not affect cell viability. However, it contributed to decrease in DNA and collagen biosynthesis, increase in prolidase activity and intracellular proline concentration as well as increase in the expression of iNOS, NF-κB, mTOR, HIF-1α, COX-2, AMPK, Atg7 and Beclin-1 in MCF-7shPRODH/POX cells. In these cells, glycyl-proline (GlyPro, substrate for prolidase) further inhibited DNA and collagen biosynthesis, maintained high prolidase activity, intracellular concentration of proline and up-regulated HIF-1α, AMPK, Atg7 and Beclin-1, compared to GlyPro-treated MCF-7 cells. In MCF-7 cells, GlyPro increased collagen biosynthesis, concentration of proline and expression of caspase-3, cleaved caspases -3 and -9, iNOS, NF-κB, COX-2 and AMPKβ. PRODH/POX knock-down contributed to pro-survival autophagy pathways in MCF-7 cells and GlyPro-derived proline augmented this process. However, GlyPro induced apoptosis in PRODH/POX-expressing MCF-7 cells as detected by up-regulation of active caspases -3 and -9. The data suggest that PRODH/POX silencing induces autophagy in MCF-7 cells and GlyPro-derived proline supports this process. PMID:29568391

  17. Immunochemical detection of food-derived polyphenols in the aorta: macrophages as a major target underlying the anti-atherosclerotic activity of polyphenols.

    Science.gov (United States)

    Kawai, Yoshichika

    2011-01-01

    It has been suggested that polyphenol-rich diets decrease the risk of cardiovascular diseases. Although studies of the bioavailability of polyphenols, particularly their absorption and metabolism, have been reported recently, the tissue and cellular distributions underlying their biological mechanisms remain unknown. It is difficult to evaluate the specific localization of tissue and/or cellular polyphenols, because the method is limited to chromatography. To overcome these difficulties, we have developed anti-polyphenol antibodies to characterize immunohistochemically the localization of polyphenols and their metabolites in vivo. Two novel monoclonal antibodies were raised against quercetin and tea catechins, which represent flavonoid-type polyphenols distributed in foods and beverages, and are expected to exhibit anti-oxidative and anti-inflammatory activities in vivo. Using these antibodies, we identified activated macrophages as a specific target of these flavonoids during the development of atherosclerotic lesions. This review describes recent findings on the molecular actions of flavonoids that underly their anti-atherosclerotic activity in vivo.

  18. Interactions between yeast lees and wine polyphenols during simulation of wine aging: I. Analysis of remnant polyphenolic compounds in the resulting wines.

    Science.gov (United States)

    Mazauric, Jean-Paul; Salmon, Jean-Michel

    2005-07-13

    Wine aging on yeast lees is a traditional enological practice used during the manufacture of wines. This technique has increased in popularity in recent years for the aging of red wines. Although wine polyphenols interact with yeast lees to a limited extent, such interactions have a large effect on the reactivity toward oxygen of wine polyphenolic compounds and yeast lees. Various domains of the yeast cell wall are protected by wine polyphenols from the action of extracellular hydrolytic enzymatic activities. Polysaccharides released during autolysis are thought to exert a significant effect on the sensory qualities of wine. We studied the chemical composition of polyphenolic compounds remaining in solution or adsorbed on yeast lees after various contact times during the simulation of wine aging. The analysis of the remnant polyphenols in the wine indicated that wine polyphenols adsorption on yeast lees follows biphasic kinetics. An initial and rapid fixation is followed by a slow, constant, and saturating fixation that reaches its maximum after about 1 week. Only very few monomeric phenolic compounds remained adsorbed on yeast lees, and no preferential adsorption of low or high polymeric size tannins occurred. The remnant condensed tannins in the wine contained fewer epigallocatechin units than the initial tannins, indicating that polar condensed tannins were preferentially adsorbed on yeast lees. Conversely, the efficiency of anthocyanin adsorption on yeast lees was unrelated to its polarity.

  19. Interactions between yeast lees and wine polyphenols during simulation of wine aging. II. Analysis of desorbed polyphenol compounds from yeast lees.

    Science.gov (United States)

    Mazauric, Jean-Paul; Salmon, Jean-Michel

    2006-05-31

    In the first part of this work, the analysis of the polyphenolic compounds remaining in the wine after different contact times with yeast lees during simulation of red wine aging was undertaken. To achieve a more precise view of the wine polyphenols adsorbed on lees during red wine aging and to establish a clear balance between adsorbed and remnant polyphenol compounds, the specific analysis of the chemical composition of the adsorbed polyphenolic compounds (condensed tannins and anthocyanins) after their partial desorbtion from yeast lees by denaturation treatments was realized in the second part of the study. The total recovery of polyphenol compounds from yeast lees was not complete, since a rather important part of the initial wine colored polyphenols, especially those with a dominant blue color component, remained strongly adsorbed on yeast lees, as monitored by color tristimulus and reflectance spectra measurements. All anthocyanins were recovered at a rather high percentage (about 62%), and it was demonstrated that they were not adsorbed in relation with their sole polarity. Very few monomeric phenolic compounds were extracted from yeast lees. With the use of drastic denaturing treatments, the total recovery of condensed tannins reached 83%. Such tannins extracted from yeast lees exhibited very high polymeric size and a rather high percentage of galloylated residues by comparison with initial wine tannins, indicating that nonpolar tannins were preferentially desorbed from yeast lees by the extraction treatments.

  20. Separation of polyphenols and arecoline from areca nut (Areca catechu L.) by solvent extraction, its antioxidant activity, and identification of polyphenols.

    Science.gov (United States)

    Chavan, Yogita V; Singhal, Rekha S

    2013-08-15

    Areca nut (Areca catechu L.) or betel nut, a commercial cash crop, is a rich source of polyphenols but also contains toxic alkaloids, mainly arecoline. Separation of these bioactive polyphenols from toxic constituents could propel the safe and beneficial use of betel nut; also it will help arecanut processing industries to produce arecoline-free products. With the aim to develop an effective method for maximum extraction of polyphenols with minimum arecoline, several factors such as nature of the solvent, pH (2-10), substrate concentration (6-14 %) and extraction time (30-150 min) under shaking conditions were evaluated. Qualitative analysis was done using spectrophotometry and high-performance liquid chromatography (HPLC). Maximum extraction of polyphenols (407.47 mg GAE g(-1)), total tannin and its antioxidant activity with minimum arecoline (1.73 mg g(-1) of sample) was achieved by using 80% acetone at pH 4 for 90 min with 10% w/v substrate under shaking conditions. Solvent extraction under optimized parameters gave maximum polyphenols with minimum extraction of arecoline, and highest ratio of polyphenols to arecoline. HPLC and liquid chromatography-mass spectrometry results confirmed the presence of catechin and epicatechin in the extract, which suggests its potential as a source of bioactives. © 2013 Society of Chemical Industry.

  1. Cocoa Polyphenols and Their Potential Benefits for Human Health

    Directory of Open Access Journals (Sweden)

    I. Andújar

    2012-01-01

    Full Text Available This paper compiles the beneficial effects of cocoa polyphenols on human health, especially with regard to cardiovascular and inflammatory diseases, metabolic disorders, and cancer prevention. Their antioxidant properties may be responsible for many of their pharmacological effects, including the inhibition of lipid peroxidation and the protection of LDL-cholesterol against oxidation, and increase resistance to oxidative stress. The phenolics from cocoa also modify the glycemic response and the lipid profile, decreasing platelet function and inflammation along with diastolic and systolic arterial pressures, which, taken together, may reduce the risk of cardiovascular mortality. Cocoa polyphenols can also modulate intestinal inflammation through the reduction of neutrophil infiltration and expression of different transcription factors, which leads to decreases in the production of proinflammatory enzymes and cytokines. The phenolics from cocoa may thus protect against diseases in which oxidative stress is implicated as a causal or contributing factor, such as cancer. They also have antiproliferative, antimutagenic, and chemoprotective effects, in addition to their anticariogenic effects.

  2. Cocoa Polyphenols and Their Potential Benefits for Human Health

    Science.gov (United States)

    Andújar, I.; Recio, M. C.; Giner, R. M.; Ríos, J. L.

    2012-01-01

    This paper compiles the beneficial effects of cocoa polyphenols on human health, especially with regard to cardiovascular and inflammatory diseases, metabolic disorders, and cancer prevention. Their antioxidant properties may be responsible for many of their pharmacological effects, including the inhibition of lipid peroxidation and the protection of LDL-cholesterol against oxidation, and increase resistance to oxidative stress. The phenolics from cocoa also modify the glycemic response and the lipid profile, decreasing platelet function and inflammation along with diastolic and systolic arterial pressures, which, taken together, may reduce the risk of cardiovascular mortality. Cocoa polyphenols can also modulate intestinal inflammation through the reduction of neutrophil infiltration and expression of different transcription factors, which leads to decreases in the production of proinflammatory enzymes and cytokines. The phenolics from cocoa may thus protect against diseases in which oxidative stress is implicated as a causal or contributing factor, such as cancer. They also have antiproliferative, antimutagenic, and chemoprotective effects, in addition to their anticariogenic effects. PMID:23150750

  3. Plant polyphenols: chemical properties, biological activities, and synthesis.

    Science.gov (United States)

    Quideau, Stéphane; Deffieux, Denis; Douat-Casassus, Céline; Pouységu, Laurent

    2011-01-17

    Eating five servings of fruits and vegetables per day! This is what is highly recommended and heavily advertised nowadays to the general public to stay fit and healthy! Drinking green tea on a regular basis, eating chocolate from time to time, as well as savoring a couple of glasses of red wine per day have been claimed to increase life expectancy even further! Why? The answer is in fact still under scientific scrutiny, but a particular class of compounds naturally occurring in fruits and vegetables is considered to be crucial for the expression of such human health benefits: the polyphenols! What are these plant products really? What are their physicochemical properties? How do they express their biological activity? Are they really valuable for disease prevention? Can they be used to develop new pharmaceutical drugs? What recent progress has been made toward their preparation by organic synthesis? This Review gives answers from a chemical perspective, summarizes the state of the art, and highlights the most significant advances in the field of polyphenol research. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Wheat aleurone polyphenols increase plasma eicosapentaenoic acid in rats

    Directory of Open Access Journals (Sweden)

    Fayçal Ounnas

    2014-08-01

    Full Text Available Methods: These studies were designed to assess whether wheat polyphenols (mainly ferulic acid [FA] increased the very-long-chain omega-3 fatty acids (VLC n-3 [eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA] in rats. Wheat aleurone (WA was used as a dietary source of wheat polyphenols. Two experiments were performed; in the first one, the rats were fed WA or control pellets (CP in presence of linseed oil (LO to provide alpha-linolenic acid (ALA, the precursor of VLC n-3. In the second one, the rats were fed WA or CP in presence of control oil (CO without ALA. The concentrations of phenolic acid metabolites in urine were also investigated. Results: The urinary concentration of conjugated FA increased with WA ingestion (p<0.05. Plasma EPA increased by 25% (p<0.05 with WA in the CO group but not in the LO group. In contrast, there was no effect of WA on plasma DHA and omega-6 fatty acids (n-6. Finally, both n-3 and n-6 in the liver remained unchanged by the WA. Conclusion: These results suggest that WA consumption has a significant effect on EPA in plasma without affecting n-6. Subsequent studies are required to examine whether these effects may explain partly the health benefits associated with whole wheat consumption.

  5. Bioactive novel polyphenols from the fruit of Manilkara zapota (Sapodilla).

    Science.gov (United States)

    Ma, Jun; Luo, Xiao-Dong; Protiva, Petr; Yang, Hui; Ma, Cuiying; Basile, Margaret J; Weinstein, I Bernard; Kennelly, Edward J

    2003-07-01

    Activity-guided fractionation of a methanol extract from the fruit of Manilkara zapota cv. Tikal resulted in the isolation of two new antioxidants, methyl 4-O-galloylchlorogenate (1) and 4-O-galloylchlorogenic acid (2), along with eight known polyphenolic antioxidants, namely, methyl chlorogenate (3), dihydromyricetin (4), quercitrin (5), myricitrin (6), (+)-catechin (7), (-)-epicatechin (8), (+)-gallocatechin (9), and gallic acid (10). Of the 10 polyphenols, 1 showed the highest antioxidant activity (IC(50) = 12.9 microM) in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical assay and displayed cytotoxicity in the HCT-116 and SW-480 human colon cancer cell lines with IC(50) values of 190 and 160 microM, respectively. Compound 2 showed high antioxidant activity (IC(50) = 23.5 microM) in the DPPH free-radical assay and displayed cytotoxicity in the HCT-116 and SW-480 human colon cancer cell lines with IC(50) values of 154 and 134 microM, respectively.

  6. Polyphenols as Promising Drugs against Main Breast Cancer Signatures

    Directory of Open Access Journals (Sweden)

    María Losada-Echeberría

    2017-11-01

    Full Text Available Breast cancer is one of the most common neoplasms worldwide, and in spite of clinical and pharmacological advances, it is still a clinical problem, causing morbidity and mortality. On the one hand, breast cancer shares with other neoplasms some molecular signatures such as an imbalanced redox state, cell cycle alterations, increased proliferation and an inflammatory status. On the other hand, breast cancer shows differential molecular subtypes that determine its prognosis and treatment. These are characterized mainly by hormone receptors especially estrogen receptors (ERs and epidermal growth factor receptor 2 (HER2. Tumors with none of these receptors are classified as triple negative breast cancer (TNBC and are associated with a worse prognosis. The success of treatments partially depends on their specificity and the adequate molecular classification of tumors. New advances in anticancer drug discovery using natural compounds have been made in the last few decades, and polyphenols have emerged as promising molecules. They may act on various molecular targets because of their promiscuous behavior, presenting several physiological effects, some of which confer antitumor activity. This review analyzes the accumulated evidence of the antitumor effects of plant polyphenols on breast cancer, with special attention to their activity on ERs and HER2 targets and also covering different aspects such as redox balance, uncontrolled proliferation and chronic inflammation.

  7. Gelatin as a carrier system for delivery of polyphenols compounds

    Directory of Open Access Journals (Sweden)

    Jovanović Aleksandra

    2017-01-01

    Full Text Available In the present study, the influence of different encapsulation techniques (lyophilization and spray drying on gelatin, as a carrier system for delivery of polyphenols compounds, on wild thyme extracts and on encapsulated extracts was investigated. FTIR analyses has shown the presence of carbohydrates, polysaccharides, polyphenols, flavonoids, monoterpenes and carboxylates in the dried extracts, while FTIR spectrum of the encapsulated extracts has shown almost exclusively gelatin-based stripes, indicating the efficient encapsulation of the active ingredients of the extracts and therefore their protection. Scanning electron microscopy has shown that the lyophilization process produced irregularly shaped particles, while spray drying formed spherical and pseudo-spherical particles with rough surface. Using the method of diffraction of laser light, it has been found that spray dried encapsulate possessed significantly lower particle size and significantly better uniformity in comparison to the lyophilized sample. According to the results obtained in differential scanning calorimetry, endothermic peak of lyophilized gelatin encapsulate appeared at higher temperature, thus it can be concluded that lyophilized sample was more thermostable than spray dried parallel. Additionally, the values of enthalpy of gelatin encapsulates were significantly higher compared to pure extracts, which confirmed the presence of stabilizing interactions between the encapsulated components and a carrier.

  8. Wine, Beer, Alcohol and Polyphenols on Cardiovascular Disease and Cancer

    Directory of Open Access Journals (Sweden)

    Sara Arranz

    2012-07-01

    Full Text Available Since ancient times, people have attributed a variety of health benefits to moderate consumption of fermented beverages such as wine and beer, often without any scientific basis. There is evidence that excessive or binge alcohol consumption is associated with increased morbidity and mortality, as well as with work related and traffic accidents. On the contrary, at the moment, several epidemiological studies have suggested that moderate consumption of alcohol reduces overall mortality, mainly from coronary diseases. However, there are discrepancies regarding the specific effects of different types of beverages (wine, beer and spirits on the cardiovascular system and cancer, and also whether the possible protective effects of alcoholic beverages are due to their alcoholic content (ethanol or to their non-alcoholic components (mainly polyphenols. Epidemiological and clinical studies have pointed out that regular and moderate wine consumption (one to two glasses a day is associated with decreased incidence of cardiovascular disease (CVD, hypertension, diabetes, and certain types of cancer, including colon, basal cell, ovarian, and prostate carcinoma. Moderate beer consumption has also been associated with these effects, but to a lesser degree, probably because of beer’s lower phenolic content. These health benefits have mainly been attributed to an increase in antioxidant capacity, changes in lipid profiles, and the anti-inflammatory effects produced by these alcoholic beverages. This review summarizes the main protective effects on the cardiovascular system and cancer resulting from moderate wine and beer intake due mainly to their common components, alcohol and polyphenols.

  9. Wine, Beer, Alcohol and Polyphenols on Cardiovascular Disease and Cancer

    Science.gov (United States)

    Arranz, Sara; Chiva-Blanch, Gemma; Valderas-Martínez, Palmira; Medina-Remón, Alex; Lamuela-Raventós, Rosa M.; Estruch, Ramón

    2012-01-01

    Since ancient times, people have attributed a variety of health benefits to moderate consumption of fermented beverages such as wine and beer, often without any scientific basis. There is evidence that excessive or binge alcohol consumption is associated with increased morbidity and mortality, as well as with work related and traffic accidents. On the contrary, at the moment, several epidemiological studies have suggested that moderate consumption of alcohol reduces overall mortality, mainly from coronary diseases. However, there are discrepancies regarding the specific effects of different types of beverages (wine, beer and spirits) on the cardiovascular system and cancer, and also whether the possible protective effects of alcoholic beverages are due to their alcoholic content (ethanol) or to their non-alcoholic components (mainly polyphenols). Epidemiological and clinical studies have pointed out that regular and moderate wine consumption (one to two glasses a day) is associated with decreased incidence of cardiovascular disease (CVD), hypertension, diabetes, and certain types of cancer, including colon, basal cell, ovarian, and prostate carcinoma. Moderate beer consumption has also been associated with these effects, but to a lesser degree, probably because of beer’s lower phenolic content. These health benefits have mainly been attributed to an increase in antioxidant capacity, changes in lipid profiles, and the anti-inflammatory effects produced by these alcoholic beverages. This review summarizes the main protective effects on the cardiovascular system and cancer resulting from moderate wine and beer intake due mainly to their common components, alcohol and polyphenols. PMID:22852062

  10. Olive Mill Waste Extracts: Polyphenols Content, Antioxidant, and Antimicrobial Activities

    Directory of Open Access Journals (Sweden)

    Inass Leouifoudi

    2015-01-01

    Full Text Available Natural polyphenols extracts have been usually associated with great bioactive properties. In this work, we investigated in vitro antioxidant and antimicrobial potential of the phenolic olive mill wastewater extracts (OWWE and the olive cake extracts (OCE. Using the Folin Ciocalteux method, OWWE contained higher total phenol content compared to OCE (8.90±0.728 g/L versus 0.95±0.017 mg/g. The phenolic compounds identification was carried out with a performance liquid chromatograph coupled to tandem mass spectrometry equipment (HPLC-ESI-MS. With this method, a list of polyphenols from OWWE and OCE was obtained. The antioxidant activity was measured in aqueous (DPPH and emulsion (BCBT systems. Using the DPPH assay, the results show that OWWE was more active than OCE and interestingly the extracts originating from mountainous areas were more active than those produced from plain areas (EC50=12.1±5.6 μg/mL; EC50=157.7±34.9 μg/mL, resp.. However, when the antioxidant activity was reversed in the BCBT, OCE produced from plain area was more potent than mountainous OCE. Testing by the gel diffusion assay, all the tested extracts have showed significant spectrum antibacterial activity against Staphylococcus aureus, whereas the biophenols extracts showed more limited activity against Escherichia coli and Streptococcus faecalis.

  11. Polyphenols as Promising Drugs against Main Breast Cancer Signatures

    Science.gov (United States)

    Herranz-López, María; Micol, Vicente

    2017-01-01

    Breast cancer is one of the most common neoplasms worldwide, and in spite of clinical and pharmacological advances, it is still a clinical problem, causing morbidity and mortality. On the one hand, breast cancer shares with other neoplasms some molecular signatures such as an imbalanced redox state, cell cycle alterations, increased proliferation and an inflammatory status. On the other hand, breast cancer shows differential molecular subtypes that determine its prognosis and treatment. These are characterized mainly by hormone receptors especially estrogen receptors (ERs) and epidermal growth factor receptor 2 (HER2). Tumors with none of these receptors are classified as triple negative breast cancer (TNBC) and are associated with a worse prognosis. The success of treatments partially depends on their specificity and the adequate molecular classification of tumors. New advances in anticancer drug discovery using natural compounds have been made in the last few decades, and polyphenols have emerged as promising molecules. They may act on various molecular targets because of their promiscuous behavior, presenting several physiological effects, some of which confer antitumor activity. This review analyzes the accumulated evidence of the antitumor effects of plant polyphenols on breast cancer, with special attention to their activity on ERs and HER2 targets and also covering different aspects such as redox balance, uncontrolled proliferation and chronic inflammation. PMID:29112149

  12. Polyphenols as Key Players for the Antileukaemic Effects of Propolis

    Directory of Open Access Journals (Sweden)

    Murtala B. Abubakar

    2014-01-01

    Full Text Available Propolis (a bee product which has a long history of medicinal use by humans has attracted a great deal of research interest in the recent time; this is due to its widely reported biological activities such as antiviral, antifungal, antibacterial, anti-inflammatory, antioxidant, and anticarcinogenic properties. Crude form of propolis and its phenolic contents have both been reported to exhibit antileukaemic effects in various leukaemia cell lines. The ability of the polyphenols found in propolis to arrest cell cycle and induce apoptosis and differentiation in addition to inhibition of cell growth and proliferation makes them promising antileukaemic agents, and hence, they are believed to be a key to the antileukaemic effects of propolis in different types of leukaemia. This paper reviews the molecular bases of antileukaemic activity of both crude propolis and individual polyphenols on various leukaemia cell lines, and it indicates that propolis has the potential to be used in both treatment and prevention of leukaemia. This however needs further evaluation by in vitro, in vivo, and epidemiological studies as well as clinical trials.

  13. INFLUENCE OF POLYPHENOLIC COMPOUNDS ON OCIMUM BASILICUM L. DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Adina Talmaciu

    2015-07-01

    Full Text Available The activities and role of phenolic compounds in the plant kingdom are well known. They are especially recognized for their function as plant growth regulators, but also for the important role in the biosynthesis process. Based on that, the aim of this work is to establish the influence of polyphenolic compounds, on the main physiological processes involved in basil cultivation under controlled conditions. Studies were carried out on sweet basil seeds (Ocimumbasilicum L. treated with different spruce bark polyphenolic extracts (aqueous extract and ultrasound assisted aqueous extract on several concentrations. The germination energy and germination capacity, plants vegetative organelles development and photoassimilatory pigments content were investigated. The results show that the Picea abies extracts, rich in phenolic compounds, have an influence on the global development of plantlets. An increased value for the growth parameters and pigments concentration was observed, compare with a control sample. Also it was shown that the effect of phenolic compounds on plants development significantly depends on their concentration.

  14. Polyphenolic extracts from cowpea (Vigna unguiculata) protect colonic myofibroblasts (CCD18Co cells) from lipopolysaccharide (LPS)-induced inflammation--modulation of microRNA 126.

    Science.gov (United States)

    Ojwang, Leonnard O; Banerjee, Nivedita; Noratto, Giuliana D; Angel-Morales, Gabriela; Hachibamba, Twambo; Awika, Joseph M; Mertens-Talcott, Susanne U

    2015-01-01

    Cowpea (Vigna unguiculata) is a drought tolerant crop with several agronomic advantages over other legumes. This study evaluated varieties from four major cowpea phenotypes (black, red, light brown and white) containing different phenolic profiles for their anti-inflammatory property on non-malignant colonic myofibroblasts (CCD18Co) cells challenged with an endotoxin (lipopolysaccharide, LPS). Intracellular reactive oxygen species (ROS) assay on the LPS-stimulated cells revealed antioxidative potential of black and red cowpea varieties. Real-time qRT-PCR analysis in LPS-stimulated cells revealed down-regulation of proinflammatory cytokines (IL-8, TNF-α, VCAM-1), transcription factor NF-κB and modulation of microRNA-126 (specific post-transcriptional regulator of VCAM-1) by cowpea polyphenolics. The ability of cowpea polyphenols to modulate miR-126 signaling and its target gene VCAM-1 were studied in LPS-stimulated endothelial cells transfected with a specific inhibitor of miR-126, and treated with 10 mg GAE/L black cowpea extract where the extract in part reversed the effect of the miR-126 inhibitor. This suggests that cowpea may exert their anti-inflammatory activities at least in part through induction of miR-126 that then down-regulate VCAM-1 mRNA and protein expressions. Overall, Cowpea therefore is promising as an anti-inflammatory dietary component.

  15. Physical and antibacterial properties of edible films formulated with apple skin polyphenols.

    Science.gov (United States)

    Du, W-X; Olsen, C W; Avena-Bustillos, R J; Friedman, M; McHugh, T H

    2011-03-01

    Fruit and vegetable skins have polyphenolic compounds, terpenes, and phenols with antimicrobial and antioxidant activity. These flavoring plant essential oil components are generally regarded as safe. Edible films made from fruits or vegetables containing apple skin polyphenols have the potential to be used commercially to protect food against contamination by pathogenic bacteria. The main objective of this study was to evaluate physical properties as well as antimicrobial activities against Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella enterica of apple skin polyphenols at 0% to 10% (w/w) concentrations in apple puree film-forming solutions formulated into edible films. Commercial apple skin polyphenol powder had a water activity of 0.44 and high total soluble phenolic compounds and antioxidant capacity (995.3 mg chlorogenic acid/100 g and 14.4 mg Trolox/g, respectively). Antimicrobial activities of edible film containing apple skin polyphenols were determined by the overlay method. Apple edible film with apple skin polyphenols was highly effective against L. monocytogenes. The minimum concentration need to inactive L. monocytogenes was 1.5%. However, apple skin polyphenols did not show any antimicrobial effect against E. coli O157:H7 and S. enterica even at 10% level. The presence of apple skin polyphenols reduced water vapor permeability of films. Apple skin polyphenols increased elongation of films and darkened the color of films. The results of the present study show that apple skin polyphenols can be used to prepare apple-based antimicrobial edible films with good physical properties for food applications by direct contact.

  16. Increased xanthine oxidase during labour--implications for oxidative stress.

    Science.gov (United States)

    Many, A; Roberts, J M

    1997-11-01

    Xanthine dehydrogenase/oxidase (XDH/XO) produces uric acid. When in the oxidase form, this production is coupled with the generation of free radicals. Hypoxia-reperfusion enhances conversion of XDH to XO. Since the placenta is exposed to short periods of hypoxia reperfusion during labour, 17 placentae of pregnancy terminated by elective caesarean section and five placentae of pregnancies terminated by caesarean section during labour were examined for XDH/XO activity. It was found that XO activity was higher in the placentae of labouring women (P = 0.003), which suggests that labour enhances conversion of XDH to XO, facilitating free radical production.

  17. A catechol oxidase AcPPO from cherimoya (Annona cherimola Mill.) is localized to the Golgi apparatus.

    Science.gov (United States)

    Olmedo, Patricio; Moreno, Adrián A; Sanhueza, Dayan; Balic, Iván; Silva-Sanzana, Christian; Zepeda, Baltasar; Verdonk, Julian C; Arriagada, César; Meneses, Claudio; Campos-Vargas, Reinaldo

    2018-01-01

    Cherimoya (Annona cherimola) is an exotic fruit with attractive organoleptic characteristics. However, it is highly perishable and susceptible to postharvest browning. In fresh fruit, browning is primarily caused by the polyphenol oxidase (PPO) enzyme catalyzing the oxidation of o-diphenols to quinones, which polymerize to form brown melanin pigment. There is no consensus in the literature regarding a specific role of PPO, and its subcellular localization in different plant species is mainly described within plastids. The present work determined the subcellular localization of a PPO protein from cherimoya (AcPPO). The obtained results revealed that the AcPPO- green fluorescent protein co-localized with a Golgi apparatus marker, and AcPPO activity was present in Golgi apparatus-enriched fractions. Likewise, transient expression assays revealed that AcPPO remained active in Golgi apparatus-enriched fractions obtained from tobacco leaves. These results suggest a putative function of AcPPO in the Golgi apparatus of cherimoya, providing new perspectives on PPO functionality in the secretory pathway, its effects on cherimoya physiology, and the evolution of this enzyme. Copyright © 2017. Published by Elsevier B.V.

  18. Two X-linked chronic granulomatous disease patients with unusual NADPH oxidase properties

    NARCIS (Netherlands)

    Wolach, Baruch; Broides, Arnon; Zeeli, Tal; Gavrieli, Ronit; de Boer, Martin; van Leeuwen, Karin; Levy, Jacov; Roos, Dirk

    2011-01-01

    Chronic granulomatous disease (CGD) is an immune deficiency syndrome caused by defects in the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, the enzyme that generates reactive oxygen species (ROS) in phagocytizing leukocytes. This study evaluates the NADPH oxidase capacity in two

  19. Catalytic aspects of a copper(II) complex: biological oxidase to ...

    Indian Academy of Sciences (India)

    BISWAJIT CHOWDHURY

    2017-10-03

    Oct 3, 2017 ... made with a Jasco model V-730 UV-Vis spectrophotometer. ..... Ligand-induced coordination changes ... Fet3 protein from yeast, a multinuclear copper oxidase ... of mutants of the multicopper oxidase Fet3p Biochem-.

  20. Resveratrol prevents high glucose-induced epithelial-mesenchymal transition in renal tubular epithelial cells by inhibiting NADPH oxidase/ROS/ERK pathway.

    Science.gov (United States)

    He, Ting; Guan, Xu; Wang, Song; Xiao, Tangli; Yang, Ke; Xu, Xinli; Wang, Junping; Zhao, Jinghong

    2015-02-15

    Resveratrol (RSV) is reported to have renoprotective activity against diabetic nephropathy, while the mechanisms underlying its function have not been fully elucidated. In this study, we investigate the effect and related mechanism of RSV against high glucose-induced epithelial to mesenchymal transition (EMT) in human tubular epithelial cells (HK-2). A typical EMT is induced by high glucose in HK-2 cells, accompanied by increased levels of reactive oxygen species (ROS). RSV exhibits a strong ability to inhibit high glucose-induced EMT by decreasing intracellular ROS levels via down-regulation of NADPH oxidase subunits NOX1 and NOX4. The activation of extracellular signal-regulated kinase (ERK1/2) is found to be involved in high glucose-induced EMT in HK-2 cells. RSV, like NADPH oxidase inhibitor diphenyleneiodonium, can block ERK1/2 activation induced by high glucose. Our results demonstrate that RSV is a potent agent against high glucose-induced EMT in renal tubular cells via inhibition of NADPH oxidase/ROS/ERK1/2 pathway. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. Azithromycin effectiveness against intracellular infections of Francisella

    Directory of Open Access Journals (Sweden)

    Mann Barbara J

    2010-04-01

    Full Text Available Abstract Background Macrolide antibiotics are commonly administered for bacterial respiratory illnesses. Azithromycin (Az is especially noted for extremely high intracellular concentrations achieved within macrophages which is far greater than the serum concentration. Clinical strains of Type B Francisella (F. tularensis have been reported to be resistant to Az, however our laboratory Francisella strains were found to be sensitive. We hypothesized that different strains/species of Francisella (including Type A may have different susceptibilities to Az, a widely used and well-tolerated antibiotic. Results In vitro susceptibility testing of Az confirmed that F. tularensis subsp. holarctica Live Vaccine Strain (LVS (Type B was not sensitive while F. philomiragia, F. novicida, and Type A F. tularensis (NIH B38 and Schu S4 strain were susceptible. In J774A.1 mouse macrophage cells infected with F. philomiragia, F. novicida, and F. tularensis LVS, 5 μg/ml Az applied extracellularly eliminated intracellular Francisella infections. A concentration of 25 μg/ml Az was required for Francisella-infected A549 human lung epithelial cells, suggesting that macrophages are more effective at concentrating Az than epithelial cells. Mutants of RND efflux components (tolC and ftlC in F. novicida demonstrated less sensitivity to Az by MIC than the parental strain, but the tolC disc-inhibition assay demonstrated increased sensitivity, indicating a complex role for the outer-membrane transporter. Mutants of acrA and acrB mutants were less sensitive to Az than the parental strain, suggesting that AcrAB is not critical for the efflux of Az in F. novicida. In contrast, F. tularensis Schu S4 mutants ΔacrB and ΔacrA were more sensitive than the parental strain, indicating that the AcrAB may be important for Az efflux in F. tularensis Schu S4. F. novicida LPS O-antigen mutants (wbtN, wbtE, wbtQ and wbtA were found to be less sensitive in vitro to Az compared to the wild

  2. Comparative analysis of lysyl oxidase (like) family members in pulmonary fibrosis.

    Science.gov (United States)

    Aumiller, Verena; Strobel, Benjamin; Romeike, Merrit; Schuler, Michael; Stierstorfer, Birgit E; Kreuz, Sebastian

    2017-03-10

    Extracellular matrix (ECM) composition and stiffness are major driving forces for the development and persistence of fibrotic diseases. Lysyl oxidase (LOX) and LOX-like (LOXL) proteins play crucial roles in ECM remodeling due to their collagen crosslinking and intracellular functions. Here, we systematically investigated LOX/L expression in primary fibroblasts and epithelial cells under fibrotic conditions, Bleomycin (BLM) induced lung fibrosis and in human IPF tissue. Basal expression of all LOX/L family members was detected in epithelial cells and at higher levels in fibroblasts. Various pro-fibrotic stimuli broadly induced LOX/L expression in fibroblasts, whereas specific induction of LOXL2 and partially LOX was observed in epithelial cells. Immunohistochemical analysis of lung tissue from 14 IPF patients and healthy donors revealed strong induction of LOX and LOXL2 in bronchial and alveolar epithelium as well as fibroblastic foci. Using siRNA experiments we observed that LOXL2 and LOXL3 were crucial for fibroblast-to-myofibroblast transition (FMT). As FMT could only be reconstituted with an enzymatically active LOXL2 variant, we conclude that LOXL2 enzymatic function is crucial for fibroblast transdifferentiation. In summary, our study provides a comprehensive analysis of the LOX/L family in fibrotic lung disease and indicates prominent roles for LOXL2/3 in fibroblast activation and LOX/LOXL2 in IPF.

  3. Metabonomics revealed xanthine oxidase-induced oxidative stress and inflammation in the pathogenesis of diabetic nephropathy.

    Science.gov (United States)

    Liu, Jingping; Wang, Chengshi; Liu, Fang; Lu, Yanrong; Cheng, Jingqiu

    2015-03-01

    Diabetic nephropathy (DN) is a serious complication of diabetes mellitus (DM), which is a major public health problem in the world. To reveal the metabolic changes associated with DN, we analyzed the serum, urine, and renal extracts obtained from control and streptozotocin (STZ)-induced DN rats by (1)H NMR-based metabonomics and multivariate data analysis. A significant difference between control and DN rats was revealed in metabolic profiles, and we identified several important DN-related metabolites including increased levels of allantoin and uric acid (UA) in the DN rats, suggesting that disturbed purine metabolism may be involved in the DN. Combined with conventional histological and biological methods, we further demonstrated that xanthine oxidase (XO), a key enzyme for purine catabolism, was abnormally activated in the kidney of diabetic rats by hyperglycemia. The highly activated XO increased the level of intracellular ROS, which caused renal injury by direct oxidative damage to renal cells, and indirect inducing inflammatory responses via activating NF-κB signaling pathway. Our study highlighted that metabonomics is a promising tool to reveal the metabolic changes and the underlying mechanism involved in the pathogenesis of DN.

  4. Leonurine (SCM-198) attenuates myocardial fibrotic response via inhibition of NADPH oxidase 4.

    Science.gov (United States)

    Liu, Xin-Hua; Pan, Li-Long; Deng, Hai-Yan; Xiong, Qing-Hui; Wu, Dan; Huang, Guo-Ying; Gong, Qi-Hai; Zhu, Yi-Zhun

    2013-01-01

    In our previous studies, we have reported that leonurine, a plant phenolic alkaloid in Herba leonuri, exerted cardioprotective properties in a number of preclinical experiments. Herein, we investigated the roles and the possible mechanisms of leonurine for reducing fibrotic responses in angiotensin II (Ang II)-stimulated primary neonatal rat cardiac fibroblasts and post-myocardial infarction (MI) rats. In in vitro experiments performed in neonatal rat cardiac fibroblasts, leonurine (10-20 μM) pretreatment attenuated Ang II-induced activation of extracellular signal-regulated kinase 1/2, production of intracellular reactive oxygen species (ROS), expression and activity of matrix metalloproteinase (MMP)-2/9, and expression of α-smooth muscle actin and types I and III collagen. A small interfering RNA-mediated knockdown strategy for NADPH oxidase 4 (Nox4) revealed that Nox4 was required for Ang II-induced activation of cardiac fibroblasts. In vivo studies using a post-MI model in rats indicated that administration of leonurine inhibited myocardial fibrosis while reducing cardiac Nox4 expression, ROS production, NF-κB activation, and plasma MMP-2 activity. In conclusion, our results provide the first evidence that leonurine could prevent cardiac fibrosis and the activation of cardiac fibroblasts partly through modulation of a Nox4-ROS pathway. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Neuroprotection of taurine against reactive oxygen species is associated with inhibiting NADPH oxidases.

    Science.gov (United States)

    Han, Zhou; Gao, Li-Yan; Lin, Yu-Hui; Chang, Lei; Wu, Hai-Yin; Luo, Chun-Xia; Zhu, Dong-Ya

    2016-04-15

    It is well established that taurine shows potent protection against glutamate-induced injury to neurons in stroke. The neuroprotection may result from multiple mechanisms. Increasing evidences suggest that NADPH oxidases (Nox), the primary source of superoxide induced by N-methyl-d-aspartate (NMDA) receptor activation, are involved in the process of oxidative stress. We found that 100μM NMDA induced oxidative stress by increasing the reactive oxygen species level, which contributed to the cell death, in vitro. Neuron cultures pretreated with 25mM taurine showed lower percentage of death cells and declined reactive oxygen species level. Moreover, taurine attenuated Nox2/Nox4 protein expression and enzyme activity and declined intracellular calcium intensity during NMDA-induced neuron injury. Additionally, taurine also showed neuroprotection against H2O2-induced injury, accompanying with Nox inhibition. So, we suppose that protection of taurine against reactive oxygen species during NMDA-induced neuron injury is associated with Nox inhibition, probably in a calcium-dependent manner. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Cytochrome cbb3 of Thioalkalivibrio is a Na+-pumping cytochrome oxidase

    NARCIS (Netherlands)

    Muntyan, M.S.; Cherepanov, D.A.; Malinen, A.M.; Bloch, D.A.; Sorokin, D.Y.; Severina, I.I.; Ivashina, T.V.; Lahti, R.; Muyzer, G.; Skulachev, V.P.

    2015-01-01

    Cytochrome c oxidases (Coxs) are the basic energy transducers in the respiratory chain of the majority of aerobic organisms. Coxs studied to date are redox-driven proton-pumping enzymes belonging to one of three subfamilies: A-, B-, and C-type oxidases. The C-type oxidases (cbb3 cytochromes), which

  7. Effects of green tea polyphenols, insulin-like growth factor I and glucose on developmental competence of bovine oocytes

    Directory of Open Access Journals (Sweden)

    Zhengguang Wang

    2012-12-01

    Full Text Available The present study examined the effects of green tea polyphenols (GTP, insulin-like growth factor-I (IGF-I and glucose on oocyte in vitro maturation, subsequent embryo development and blastocyst quality in bovine. Cumulus-oocyte complexes (COC were aspirated from the ovaries and cultured in synthetic oviduct fluid supplemented with MEM amino acids (SOFaa media supplemented with one of the following supplements: GTP (0, 10, 15 and 20 µM, IGF-I (0, 50, 100 and 150 ng/mL or glucose (0, 1.5, 5.6 and 20 mM for 24 h. The results showed that oocytes cultured in media supplemented with 15 µM GTP, 100 ng/mL IGF-I and 5.6 mM glucose, in separate experiments, have higher cleavage and blastocyst rates compared with oocytes cultured in media without or with other concentration of GTP, IGF-I and glucose. Then these three substances with the concentration above were added together into SOFaa media and constituted a modified medium (Modified SOFaa. The COC were cultured in control SOFaa media and modified SOFaa media, respectively. The results showed that modified SOFaa media increased the intracellular glutathione concentration of matured oocytes, blastocyst rates and total cell numbers and cell numbers of inner cell mass per blastocyst compared with the control. Supplementing of GTP, IGF-I and glucose synchronously to maturation media can increase the intracellular GSH concentration of oocytes after in vitro maturation, and improve the embryo development and blastocyst quality in bovine.

  8. Intracellular bacteria: the origin of dinoflagellate toxicity.

    Science.gov (United States)

    Silva, E S

    1990-01-01

    Dinoflagellate blooms of the same species have been registered either as toxic or nontoxic and, in the latter case, toxicity may be of different types. A hypothesis has been formulated according to which the bacteria having in some way taken part in the toxin formation are either inside the dinoflagellate cell or in the nutritive liquid. The presence of intracellular bacteria in those microorganisms has been studied mainly in material from cultures, a few from the sea, and several strains were isolated from different species. Experiments with crossed inoculations have shown that the bacterial strain from Gonyaulax tamarensis caused the cells of some other species to become toxic. From nontoxic clonal cultures of Prorocentrum balticum, Glenodinium foliaceum, and Gyrodinium instriatum, after inoculation of that bacterial strain, cultures were obtained whose cell extracts showed the same kind of toxicity as G. tamarensis. No toxic action could be found in the extracts of the bacterial cells form the assayed strains. The interference of intracellular bacteria in the metabolism of dinoflagellates must be the main cause of their toxicity.

  9. Fluorescent nanoparticles for intracellular sensing: a review.

    Science.gov (United States)

    Ruedas-Rama, Maria J; Walters, Jamie D; Orte, Angel; Hall, Elizabeth A H

    2012-11-02

    Fluorescent nanoparticles (NPs), including semiconductor NPs (Quantum Dots), metal NPs, silica NPs, polymer NPs, etc., have been a major focus of research and development during the past decade. The fluorescent nanoparticles show unique chemical and optical properties, such as brighter fluorescence, higher photostability and higher biocompatibility, compared to classical fluorescent organic dyes. Moreover, the nanoparticles can also act as multivalent scaffolds for the realization of supramolecular assemblies, since their high surface to volume ratio allow distinct spatial domains to be functionalized, which can provide a versatile synthetic platform for the implementation of different sensing schemes. Their excellent properties make them one of the most useful tools that chemistry has supplied to biomedical research, enabling the intracellular monitoring of many different species for medical and biological purposes. In this review, we focus on the developments and analytical applications of fluorescent nanoparticles in chemical and biological sensing within the intracellular environment. The review also points out the great potential of fluorescent NPs for fluorescence lifetime imaging microscopy (FLIM). Finally, we also give an overview of the current methods for delivering of fluorescent NPs into cells, where critically examine the benefits and liabilities of each strategy. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Mechanisms of cellular invasion by intracellular parasites.

    Science.gov (United States)

    Walker, Dawn M; Oghumu, Steve; Gupta, Gaurav; McGwire, Bradford S; Drew, Mark E; Satoskar, Abhay R

    2014-04-01

    Numerous disease-causing parasites must invade host cells in order to prosper. Collectively, such pathogens are responsible for a staggering amount of human sickness and death throughout the world. Leishmaniasis, Chagas disease, toxoplasmosis, and malaria are neglected diseases and therefore are linked to socio-economical and geographical factors, affecting well-over half the world's population. Such obligate intracellular parasites have co-evolved with humans to establish a complexity of specific molecular parasite-host cell interactions, forming the basis of the parasite's cellular tropism. They make use of such interactions to invade host cells as a means to migrate through various tissues, to evade the host immune system, and to undergo intracellular replication. These cellular migration and invasion events are absolutely essential for the completion of the lifecycles of these parasites and lead to their for disease pathogenesis. This review is an overview of the molecular mechanisms of protozoan parasite invasion of host cells and discussion of therapeutic strategies, which could be developed by targeting these invasion pathways. Specifically, we focus on four species of protozoan parasites Leishmania, Trypanosoma cruzi, Plasmodium, and Toxoplasma, which are responsible for significant morbidity and mortality.

  11. [Intracellular signaling mechanisms in thyroid cancer].

    Science.gov (United States)

    Mondragón-Terán, Paul; López-Hernández, Luz Berenice; Gutiérrez-Salinas, José; Suárez-Cuenca, Juan Antonio; Luna-Ceballos, Rosa Isela; Erazo Valle-Solís, Aura

    2016-01-01

    Thyroid cancer is the most common malignancy of the endocrine system, the papillary variant accounts for 80-90% of all diagnosed cases. In the development of papillary thyroid cancer, BRAF and RAS genes are mainly affected, resulting in a modification of the system of intracellular signaling proteins known as «protein kinase mitogen-activated» (MAPK) which consist of «modules» of internal signaling proteins (Receptor/Ras/Raf/MEK/ERK) from the cell membrane to the nucleus. In thyroid cancer, these signanling proteins regulate diverse cellular processes such as differentiation, growth, development and apoptosis. MAPK play an important role in the pathogenesis of thyroid cancer as they are used as molecular biomarkers for diagnostic, prognostic and as possible therapeutic molecular targets. Mutations in BRAF gene have been correlated with poor response to treatment with traditional chemotherapy and as an indicator of poor prognosis. To review the molecular mechanisms involved in intracellular signaling of BRAF and RAS genes in thyroid cancer. Molecular therapy research is in progress for this type of cancer as new molecules have been developed in order to inhibit any of the components of the signaling pathway (RET/PTC)/Ras/Raf/MEK/ERK; with special emphasis on the (RET/PTC)/Ras/Raf section, which is a major effector of ERK pathway. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  12. Enhanced production of glucose oxidase from UVmutant of ...

    African Journals Online (AJOL)

    UV rays were used as mutagen in wild type strain of Aspergillus niger for enhanced production of glucose oxidase. After mutangenization and selection, mutant A. niger strains, resistant to 2-deoxy-Dglucose were obtained. The mutants showed 1.57 and 1.98 fold increase in activities of extra and intra cellular glucose ...

  13. Localization of Glucose Oxidase and Catalase Activities in Aspergillus niger

    NARCIS (Netherlands)

    Witteveen, Cor F.B.; Veenhuis, Marten; Visser, Jaap

    The subcellular localization of glucose oxidase (EC 1.1.3.4) in Aspergillus niger N400 (CBS 120.49) was investigated by (immuno)cytochemical methods. By these methods, the bulk of the enzyme was found to be localized in the cell wall. In addition, four different catalases (EC 1.11.1.6) were

  14. The glucose oxidase-peroxidase assay for glucose

    Science.gov (United States)

    The glucose oxidase-peroxidase assay for glucose has served as a very specific, sensitive, and repeatable assay for detection of glucose in biological samples. It has been used successfully for analysis of glucose in samples from blood and urine, to analysis of glucose released from starch or glycog...

  15. Nanoporous gold assembly of glucose oxidase for electrochemical biosensing

    DEFF Research Database (Denmark)

    Xiao, Xinxin; Ulstrup, Jens; Li, Hui

    2014-01-01

    Nanoporous gold (NPG) is composed of three-dimensional (3D) bicontinuous nanostructures with large surface area. Nano-channels inside NPG provide an ideal local environment for immobilization of enzyme molecules with expected stabilization of the protein molecules. In this work, glucose oxidase (...

  16. Gene cloning and characterization of NADH oxidase from ...

    African Journals Online (AJOL)

    The genome search of Thermococcus kodakarensis revealed three open reading frames, Tk0304, Tk1299 and Tk1392 annotated as nicotinamide adenine dinucleotide (NADH) oxidases. This study deals with cloning, and characterization of Tk0304. The gene, composed of 1320 nucleotides, encodes a protein of 439 ...

  17. Optimization of cholesterol oxidase production by Brevibacterium sp ...

    African Journals Online (AJOL)

    An ultrasound-assisted emulsification as a pretreatment for cholesterol oxidase production by submerge fermentation using Brevibacterium sp. in a batch system was studied. Medium improvement for the production employing response surface methodology (RSM) was optimized in this paper. The concentration of ...

  18. in Escherichia coli with native cholesterol oxidase expressed

    African Journals Online (AJOL)

    The structure and bio-activity of an endogenous cholesterol oxidase from Brevibacterium sp. was compared to the same enzyme exogenously expressed in Escherichia coli BL21 (DE3) with and without N- or C-terminal his-tags. The different proteins were purified with affinity and subtractive protocols. The specific activity of ...

  19. Cytokinin oxidase or dehydrogenase? Mechanism of cytokinin degradation in cereals

    DEFF Research Database (Denmark)

    Galuszka, P.; Frebort, I.; Sebela, M.

    2001-01-01

    An enzyme degrading cytokinins with isoprenoid side chain, previously named cytokinin oxidase, was purified to near homogeneity from wheat and barley grains. New techniques were developed for the enzyme activity assay and staining on native electrophoretic gels to identify the protein. The purifi...

  20. Lysyl oxidases regulate fibrillar collagen remodelling in idiopathic pulmonary fibrosis

    NARCIS (Netherlands)

    Tjin, Gavin; White, Eric S; Faiz, Alen; Sicard, Delphine; Tschumperlin, Daniel J; Mahar, Annabelle; Kable, Eleanor P W; Burgess, Janette K

    2017-01-01

    Idiopathic pulmonary fibrosis (IPF) is a progressive scarring disease of the lung with feweffective therapeutic options. Structural remodelling of the extracellular matrix [i.e. collagen cross-linkingmediated by the lysyl oxidase (LO) family of enzymes (LOX, LOXL1-4)] might contribute to disease

  1. Novel thidiazuron-derived inhibitors of cytokinin oxidase/dehydrogenase

    Czech Academy of Sciences Publication Activity Database

    Nisler, Jaroslav; Kopečný, D.; Končitíková, R.; Zatloukal, Marek; Bazgier, Václav; Berka, K.; Zalabák, D.; Briozzo, P.; Strnad, Miroslav; Spíchal, Lukáš

    2016-01-01

    Roč. 92, 1-2 (2016), s. 235-248 ISSN 0167-4412 R&D Projects: GA MŠk(CZ) LO1204; GA ČR GA15-22322S Institutional support: RVO:61389030 Keywords : Cytokinin oxidase/dehydrogenase * Crystal structure * Molecular docking Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.356, year: 2016

  2. DNA damage and decrease of cellular oxidase activity in piglet ...

    African Journals Online (AJOL)

    DNA damage and decrease of cellular oxidase activity in piglet sertoli cells exposed to gossypol. Ming Zhang, Hui Yuan, Zuping He, Liyun Yuan, Jine Yi, Sijun Deng, Li Zhu, Chengzhi Guo, Yin Lu, Jing Wu, Lixin Wen, Qiang Wei, Liqun Xue ...

  3. [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.

  4. Differential protective effects of red wine polyphenol extracts (RWEs) on colon carcinogenesis.

    Science.gov (United States)

    Mazué, Frédéric; Delmas, Dominique; Murillo, Genoveva; Saleiro, Diana; Limagne, Emeric; Latruffe, Norbert

    2014-04-01

    Various epidemiological studies have shown that a regular and moderate consumption of red wine is correlated with a decreased relative risk of developing coronary heart disease and cancer. These health benefits are commonly attributed to high contents of polyphenols, particularly resveratrol, representing important sources of antioxidants. However, resveratrol does not seem to be the only bioactive compound present in the wine which contains numerous other polyphenols. The present study investigates the efficiency of red wine extracts (RWEs), containing different polyphenols, on colon cancer cell proliferation in vitro and on colonic aberrant crypt foci (ACF) in vivo. Proliferation, cell cycle analysis and incidence of ACF were monitored to examine the effects of RWEs. RWEs derived from a long vinification process exhibit superior anti-proliferative activity in colon cancer cells and prevent the appearance of ACF in mice. Interestingly, quercetin and resveratrol, representing two major bio-active polyphenols, exhibit synergistic anti-proliferative effects. These data suggest that the efficacy of RWEs on colon carcinogenesis may depend on the polyphenolic content, synergistic interaction of bio-active polyphenols and modulation of cellular uptake of polyphenols.

  5. Variability of the polyphenolic composition of cider apple (Malus domestica) fruits and juices.

    Science.gov (United States)

    Guyot, Sylvain; Marnet, Nathalie; Sanoner, Philippe; Drilleau, Jean-François

    2003-10-08

    Five French cider apple varieties were compared on the basis of their detailed polyphenol profile in the cortex and in the juices. Among the factors studied, variety was the most important variability factor in fruits, whereas polyphenol profiles showed an overall stability from one year to another, and a limited decrease of polyphenol concentration was observed during the starch regression period of fruit maturation. In juices, procyanidins remained the preponderant polyphenol class with concentrations up to 2.4 g/L even in centrifuged juices. Compared to the fruits, the average degree of polymerization of procyanidins was significantly reduced in the juice. Centrifugation of the crude juice had only minor effects on the polyphenol composition. For one variety, highly polymerized procyanidins with average degrees of polymerization of 25 were shown to be soluble in the centrifuged juice at a concentration of close to 1.2 g/L. Oxygenation of the juices during processing resulted in a significant decrease of all classes of native polyphenols. Catechins and procyanidins were particularly affected by oxidation, whereas caffeoylquinic acid was partly preserved. The transfer of polyphenols after pressing was maximal for dihydrochalcones and minimal for procyanidins with extraction yield values close to 80 and 30%, respectively.

  6. Skin photoprotection by natural polyphenols: Anti-inflammatory, anti-oxidant and DNA repair mechanisms

    Science.gov (United States)

    Nichols, Joi A.; Katiyar, Santosh K.

    2009-01-01

    Epidemiological, clinical and laboratory studies have implicated solar ultraviolet (UV) radiation in various skin diseases including premature aging of the skin and melanoma and nonmelanoma skin cancers. Chronic UV radiation exposure-induced skin diseases or skin disorders are caused by the excessive induction of inflammation, oxidative stress and DNA damage, etc.. The use of chemopreventive agents, such as plant polyphenols, to inhibit these events in UV-exposed skin is gaining attention. Chemoprevention refers to the use of agents that can inhibit, reverse, or retard the process of these harmful events in the UV-exposed skin. A wide variety of polyphenols or phytochemicals, most of which are dietary supplements, have been reported to possess substantial skin photoprotective effects. This review article summarizes the photoprotective effects of some selected polyphenols, such as green tea polyphenols, grape seed proanthocyanidins, resveratrol, silymarin and genistein, on UV-induced skin inflammation, oxidative stress, and DNA damage, etc., with a focus on mechanisms underlying the photoprotective effects of these polyphenols. The laboratory studies conducted in animal models, suggest that these polyphenols have the ability to protect the skin from the adverse effects of UV radiation, including the risk of skin cancers. It is suggested that polyphenols may favorably supplement sunscreens protection, and may be useful for skin diseases associated with solar UV radiation-induced inflammation, oxidative stress and DNA damage. PMID:19898857

  7. Skin photoprotection by natural polyphenols: anti-inflammatory, antioxidant and DNA repair mechanisms.

    Science.gov (United States)

    Nichols, Joi A; Katiyar, Santosh K

    2010-03-01

    Epidemiological, clinical and laboratory studies have implicated solar ultraviolet (UV) radiation in various skin diseases including, premature aging of the skin and melanoma and non-melanoma skin cancers. Chronic UV radiation exposure-induced skin diseases or skin disorders are caused by the excessive induction of inflammation, oxidative stress and DNA damage, etc. The use of chemopreventive agents, such as plant polyphenols, to inhibit these events in UV-exposed skin is gaining attention. Chemoprevention refers to the use of agents that can inhibit, reverse or retard the process of these harmful events in the UV-exposed skin. A wide variety of polyphenols or phytochemicals, most of which are dietary supplements, have been reported to possess substantial skin photoprotective effects. This review article summarizes the photoprotective effects of some selected polyphenols, such as green tea polyphenols, grape seed proanthocyanidins, resveratrol, silymarin and genistein, on UV-induced skin inflammation, oxidative stress and DNA damage, etc., with a focus on mechanisms underlying the photoprotective effects of these polyphenols. The laboratory studies conducted in animal models suggest that these polyphenols have the ability to protect the skin from the adverse effects of UV radiation, including the risk of skin cancers. It is suggested that polyphenols may favorably supplement sunscreens protection, and may be useful for skin diseases associated with solar UV radiation-induced inflammation, oxidative stress and DNA damage.

  8. Dietary polyphenol supplementation prevents alterations of spatial navigation in middle-aged mice

    Directory of Open Access Journals (Sweden)

    Julien eBensalem

    2016-02-01

    Full Text Available Spatial learning and memory deficits associated with hippocampal synaptic plasticity impairments are commonly observed during aging. Besides, the beneficial role of dietary polyphenols has been suggested as potential functional food candidates to prevent this memory decline. Indeed, polyphenols could potentiate the signaling pathways of synaptic plasticity underlying learning and memory. In this study, spatial learning deficits of middle-aged mice were first highlighted and characterized according to navigation patterns in the Morris water maze task. An eight-week polyphenol-enriched diet, containing a polyphenol-rich extract from grape and blueberry (PEGB (from the Neurophenols Consortium with high contents of flavonoids, stilbenes and phenolic acids, was then successful in reversing these age-induced effects. The use of spatial strategies was indeed delayed with aging whereas a polyphenol supplementation could promote the occurrence of spatial strategies. These behavioral results were associated with neurobiological changes: while the expression of hippocampal CaMKII mRNA levels was reduced in middle-aged animals, the polyphenol-enriched diet could rescue them. Besides, an increased expression of NGF mRNA levels was also observed in supplemented adult and middle-aged mice. Thus these data suggest that supplementation with polyphenols could be an efficient nutritional way to prevent age-induced cognitive decline.

  9. Polyphenol-enriched berry extracts naturally modulate reactive proteins in model foods.

    Science.gov (United States)

    Lila, Mary Ann; Schneider, Maggie; Devlin, Amy; Plundrich, Nathalie; Laster, Scott; Foegeding, E Allen

    2017-12-13

    Healthy foods like polyphenol-rich berries and high quality edible proteins are in demand in today's functional food marketplace, but it can be difficult to formulate convenient food products with physiologically-relevant amounts of these ingredients and still maintain product quality. In part, this is because proteins can interact with other food ingredients and precipitate destabilizing events, which can disrupt food structure and diminish shelf life. Proteins in foods can also interact with human receptors to provoke adverse consequences such as allergies. When proteins and polyphenols were pre-aggregated into stable colloidal particles prior to use as ingredients, highly palatable food formulations (with reduced astringency of polyphenols) could be prepared, and the overall structural properties of food formulations were significantly improved. All of the nutritive and phytoactive benefits of the proteins and concentrated polyphenols remained highly bioavailable, but the protein molecules in the particle matrix did not self-aggregate into networks or react with other food ingredients. Both the drainage half-life (a marker of structural stability) and the yield stress (resistance to flow) of model foams made with the protein-polyphenol particles were increased in a dose-dependent manner. Of high significance in this complexation process, the reactive allergenic epitopes of certain proteins were effectively blunted by binding with polyphenols, attenuating the allergenicity of the food proteins. Porcine macrophages produced TNF-α proinflammatory cytokine when provoked with whey protein, but, this response was blocked completely when the cells were stimulated with particles that complexed whey protein with cinnamon-derived polyphenols. Cytokine and chemokine production characteristic of allergic reactions were blocked by the polyphenols, allowing for the potential creation of hypoallergenic protein-berry polyphenol enriched foods.

  10. Mangifera indica L. extract (Vimang) and its main polyphenol mangiferin prevent mitochondrial oxidative stress in atherosclerosis-prone hypercholesterolemic mouse.

    Science.gov (United States)

    Pardo-Andreu, Gilberto L; Paim, Bruno A; Castilho, Roger F; Velho, Jesus A; Delgado, René; Vercesi, Anibal E; Oliveira, Helena C F

    2008-05-01

    Atherosclerosis is linked to a number of oxidative events ranging from low-density lipoprotein (LDL) oxidation to the increased production of intracellular reactive oxygen species (ROS). We have recently demonstrated that liver mitochondria isolated from the atherosclerosis-prone hypercholesterolemic LDL receptor knockout (LDLr(-/-)) mice have lower content of NADP(H)-linked substrates than the controls and, as consequence, higher sensitivity to oxidative stress and mitochondrial membrane permeability transition (MPT). In the present work, we show that oral supplementation with the antioxidants Mangifera indica L. extract (Vimang) or its main polyphenol mangiferin shifted the sensitivity of LDLr(-/-) liver mitochondria to MPT to control levels. These in vivo treatments with Vimang and mangiferin also significantly reduced ROS generation by both isolated LDLr(-/-) liver mitochondria and spleen lymphocytes. In addition, these antioxidant treatments prevented mitochondrial NAD(P)H-linked substrates depletion and NADPH spontaneous oxidation. In summary, Vimang and mangiferin spared the endogenous reducing equivalents (NADPH) in LDLr(-/-) mice mitochondria correcting their lower antioxidant capacity and restoring the organelle redox homeostasis. The effective bioavailability of these compounds makes them suitable antioxidants with potential use in atherosclerosis susceptible conditions.

  11. Polyphenol-Rich Strawberry Extract Protects Human Dermal Fibroblasts against Hydrogen Peroxide Oxidative Damage and Improves Mitochondrial Functionality

    Directory of Open Access Journals (Sweden)

    Francesca Giampieri

    2014-06-01

    Full Text Available Strawberry bioactive compounds are widely known to be powerful antioxidants. In this study, the antioxidant and anti-aging activities of a polyphenol-rich strawberry extract were evaluated using human dermal fibroblasts exposed to H2O2. Firstly, the phenol and flavonoid contents of strawberry extract were studied, as well as the antioxidant capacity. HPLC-DAD analysis was performed to determine the vitamin C and β-carotene concentration, while HPLC-DAD/ESI-MS analysis was used for anthocyanin identification. Strawberry extract presented a high antioxidant capacity, and a relevant concentration of vitamins and phenolics. Pelargonidin- and cyanidin-glycosides were the most representative anthocyanin components of the fruits. Fibroblasts incubated with strawberry extract and stressed with H2O2 showed an increase in cell viability, a smaller intracellular amount of ROS, and a reduction of membrane lipid peroxidation and DNA damage. Strawberry extract was also able to improve mitochondrial functionality, increasing the basal respiration of mitochondria and to promote a regenerative capacity of cells after exposure to pro-oxidant stimuli. These findings confirm that strawberries possess antioxidant properties and provide new insights into the beneficial role of strawberry bioactive compounds on protecting skin from oxidative stress and aging.

  12. Polyphenol-rich strawberry extract protects human dermal fibroblasts against hydrogen peroxide oxidative damage and improves mitochondrial functionality.

    Science.gov (United States)

    Giampieri, Francesca; Alvarez-Suarez, José M; Mazzoni, Luca; Forbes-Hernandez, Tamara Y; Gasparrini, Massimiliano; Gonzàlez-Paramàs, Ana M; Santos-Buelga, Celestino; Quiles, José L; Bompadre, Stefano; Mezzetti, Bruno; Battino, Maurizio

    2014-06-11

    Strawberry bioactive compounds are widely known to be powerful antioxidants. In this study, the antioxidant and anti-aging activities of a polyphenol-rich strawberry extract were evaluated using human dermal fibroblasts exposed to H2O2. Firstly, the phenol and flavonoid contents of strawberry extract were studied, as well as the antioxidant capacity. HPLC-DAD analysis was performed to determine the vitamin C and β-carotene concentration, while HPLC-DAD/ESI-MS analysis was used for anthocyanin identification. Strawberry extract presented a high antioxidant capacity, and a relevant concentration of vitamins and phenolics. Pelargonidin- and cyanidin-glycosides were the most representative anthocyanin components of the fruits. Fibroblasts incubated with strawberry extract and stressed with H2O2 showed an increase in cell viability, a smaller intracellular amount of ROS, and a reduction of membrane lipid peroxidation and DNA damage. Strawberry extract was also able to improve mitochondrial functionality, increasing the basal respiration of mitochondria and to promote a regenerative capacity of cells after exposure to pro-oxidant stimuli. These findings confirm that strawberries possess antioxidant properties and provide new insights into the beneficial role of strawberry bioactive compounds on protecting skin from oxidative stress and aging.

  13. Use of Curcumin, a Natural Polyphenol for Targeting Molecular Pathways in Treating Age-Related Neurodegenerative Diseases

    Directory of Open Access Journals (Sweden)

    Panchanan Maiti

    2018-05-01

    Full Text Available Progressive accumulation of misfolded amyloid proteins in intracellular and extracellular spaces is one of the principal reasons for synaptic damage and impairment of neuronal communication in several neurodegenerative diseases. Effective treatments for these diseases are still lacking but remain the focus of much active investigation. Despite testing several synthesized compounds, small molecules, and drugs over the past few decades, very few of them can inhibit aggregation of amyloid proteins and lessen their neurotoxic effects. Recently, the natural polyphenol curcumin (Cur has been shown to be a promising anti-amyloid, anti-inflammatory and neuroprotective agent for several neurodegenerative diseases. Because of its pleotropic actions on the central nervous system, including preferential binding to amyloid proteins, Cur is being touted as a promising treatment for age-related brain diseases. Here, we focus on molecular targeting of Cur to reduce amyloid burden, rescue neuronal damage, and restore normal cognitive and sensory motor functions in different animal models of neurodegenerative diseases. We specifically highlight Cur as a potential treatment for Alzheimer’s, Parkinson’s, Huntington’s, and prion diseases. In addition, we discuss the major issues and limitations of using Cur for treating these diseases, along with ways of circumventing those shortcomings. Finally, we provide specific recommendations for optimal dosing with Cur for treating neurological diseases.

  14. Inactivation of 1-aminocyclopropane-1-carboxylate oxidase involves oxidative modifications.

    Science.gov (United States)

    Barlow, J N; Zhang, Z; John, P; Baldwin, J E; Schofield, C J

    1997-03-25

    1-Aminocyclopropane-1-carboxylate (ACC) oxidase catalyzes the final step in the biosynthesis of the plant signaling molecule ethylene. It is a member of the ferrous iron dependent family of oxidases and dioxygenases and is unusual in that it displays a very short half-life under catalytic conditions, typically less than 20 min, and a requirement for CO2 as an activator. The rates of inactivation of purified, recombinant ACC oxidase from tomato under various combinations of substrates and cofactors were measured. Inactivation was relatively slow in the presence of buffer alone (t1/2 > 1 h), but fast in the presence of ferrous iron and ascorbate (t1/2 approximately 10 min). The rate of iron/ascorbate-mediated inactivation was increased by the addition of ACC, unaffected by the addition of CO2 at saturation (supplied as bicarbonate) but decreased by the addition of catalase or ACC + CO2 at saturation (supplied as bicarbonate). Iron/ascorbate-mediated inactivation was accompanied by partial proteolysis as observed by SDS-PAGE analysis. The fragmentation pattern was altered when ACC was also included, suggesting that ACC can bind to ACC oxidase in the absence of bicarbonate. N-terminal sequencing of fragments resulted in identification of an internal cleavage site which we propose is proximate to active-site bound iron. Thus, ACC oxidase inactivates via relatively slow partial unfolding of the catalytically active conformation, oxidative damage mediated via hydrogen peroxide which is catalase protectable and oxidative damage to the active site which results in partial proteolysis and is not catalase protectable.

  15. Expression Studies of Gibberellin Oxidases in Developing Pumpkin Seeds1

    Science.gov (United States)

    Frisse, Andrea; Pimenta, Maria João; Lange, Theo

    2003-01-01

    Two cDNA clones, 3-ox and 2-ox, have been isolated from developing pumpkin (Cucurbita maxima) embryos that show significant amino acid homology to gibberellin (GA) 3-oxidases and 2-oxidases, respectively. Recombinant fusion protein of clone 3-ox converted GA12-aldehyde, GA12, GA15, GA24, GA25, and GA9 to GA14-aldehyde, GA14, GA37, GA36, GA13, and GA4, respectively. Recombinant 2-ox protein oxidized GA9, GA4, and GA1 to GA51, GA34, and GA8, respectively. Previously cloned GA 7-oxidase revealed additional 3β-hydroxylation activity of GA12. Transcripts of this gene were identified in endosperm and embryo of the developing seed by quantitative reverse transcriptase-polymerase chain reaction and localized in protoderm, root apical meristem, and quiescent center by in situ hybridization. mRNA of the previously cloned GA 20-oxidase from pumpkin seeds was localized in endosperm and in tissues of protoderm, ground meristem, and cotyledons of the embryo. However, transcripts of the recently cloned GA 20-oxidase from pumpkin seedlings were found all over the embryo, and in tissues of the inner seed coat at the micropylar end. Previously cloned GA 2β,3β-hydroxylase mRNA molecules were specifically identified in endosperm tissue. Finally, mRNA molecules of the 3-ox and 2-ox genes were found in the embryo only. 3-ox transcripts were localized in tissues of cotyledons, protoderm, and inner cell layers of the root apical meristem, and 2-ox transcripts were found in all tissues of the embryo except the root tips. These results indicate tissue-specific GA-biosynthetic pathways operating within the developing seed. PMID:12644672

  16. Pulse radiolysis studies of bergenin, an isocoumarin polyphenolic derivative

    International Nuclear Information System (INIS)

    Singh, Umang; Srinivasan, R.; Barik, A.; Priyadarsini, K.I.

    2008-01-01

    Bergenin, a polyphenolic isocoumarin derivative, isolated from medicinal plant Caesalpinia digynae, has been subjected for OH and oxidizing radical reactions using pulse radiolysis technique coupled with absorption detection. OH radicals cause multiple reactions, producing transients absorbing with maxima at 440 nm and 500 nm. By comparing the spectra and decay kinetics with that produced by N 3 radicals, the species absorbing at 440 nm is assigned to phenoxyl type radical and the one absorbing at 500 nm to be a hydroxyl-radical adduct, which has been found to be reducing in nature. Bergenin also reacts with peroxyl radicals, with rate constants of 4.2 x 10 6 M -1 s -1 . (author)

  17. Pulse radiolysis studies of bergenin, an isocoumarin polyphenolic derivative

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Umang; Srinivasan, R; Barik, A; Priyadarsini, K I [Radiation and Photochemistry Div., Bhabha Atomic Research Centre, Mumbai (India)

    2008-01-15

    Bergenin, a polyphenolic isocoumarin derivative, isolated from medicinal plant Caesalpinia digynae, has been subjected for OH and oxidizing radical reactions using pulse radiolysis technique coupled with absorption detection. OH radicals cause multiple reactions, producing transients absorbing with maxima at 440 nm and 500 nm. By comparing the spectra and decay kinetics with that produced by N{sub 3} radicals, the species absorbing at 440 nm is assigned to phenoxyl type radical and the one absorbing at 500 nm to be a hydroxyl-radical adduct, which has been found to be reducing in nature. Bergenin also reacts with peroxyl radicals, with rate constants of 4.2 x 10{sup 6} M{sup -1}s{sup -1}. (author)

  18. In vitro antimicrobial activity of pistachio (Pistacia vera L.) polyphenols.

    Science.gov (United States)

    Bisignano, Carlo; Filocamo, Angela; Faulks, Richard M; Mandalari, Giuseppina

    2013-04-01

    We investigated the antimicrobial properties of polyphenol-rich fractions derived from raw shelled and roasted salted pistachios. American Type Culture Collection (ATCC), food and clinical isolates, of Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Pseudomonas mirabilis), Gram-positive bacteria (Listeria monocytogenes, Enterococcus hirae, Enterococcus faecium, Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus aureus), the yeasts Candida albicans and Candida parapsilosis and the fungus Aspergillus niger were used. Pistachio extracts were active against Gram-positive bacteria with a bactericidal effect observed against L. monocytogenes (ATCC strains and food isolates), S. aureus and MRSA clinical isolates. Extracts from raw shelled pistachios were more active than those from roasted salted pistachios. The bactericidal activity of pistachio extracts could be used to help control the growth of some microorganisms in foods to improve safety and may find application as a topical treatment for S. aureus. © 2013 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  19. Evaluation of the radioprotective potential of the polyphenol norbadione A

    International Nuclear Information System (INIS)

    Le Roux, Antoine; Josset, Elodie; Benzina, Sami; Bischoff, Pierre; Nadal, Brice; Desage-El Murr, Marine; Heurtaux, Benoit; Taran, Frederic; Le Gall, Thierry; Meunier, Stephane; Denis, Jean-Marc

    2012-01-01

    There is an obvious need to develop efficient countermeasure agents for use in emergency situations or as adjuncts to radiotherapy to protect healthy tissues from the consequences of an irradiation. To this end, we have investigated the capacity of norbadione A, a polyphenol extracted from the edible mushroom Bay boletus to reduce the toxicity of ionizing radiation towards cultured cells and whole-body exposed mice. Results indicate that this compound could slightly enhance the resistance of TK6 lymphoid cells to radiation and increase the survival rate in lethally irradiated mice. However, norbadione A was found to be cytotoxic at concentrations over 30 μM in vitro. The acute toxicity of this compound also precluded its use at higher doses for enhanced in vivo radioprotection. Norbadione A may nevertheless serve as lead for development of less toxic analogs with potentially cytoprotective/radioprotective activities. (authors)

  20. Ultrasound assisted extraction of polyphenols from Punica granatum (Grenada) fruit

    International Nuclear Information System (INIS)

    Rodriguez Chanfrau, Jorge Enrique; Lopez Armas, Marilyn

    2014-01-01

    Extraction of bioactive compounds from vegetable materials is a classical operation applied in many industrial processes. Few studies have made reference to processes to obtain extracts from Punica granatum. This fruit is generally consumed as such or as fermented juices. In Cuba, it is known as grenade and numerous studies have shown antiviral, antioxidant and antimicrobial properties. Maceration process is the main used technology in the preparation of extracts from Punica granatum fruit, being this a long and expensive process. Ultrasound-assisted extractions have been proven to significantly decreased extraction time and increased extraction yields in many vegetable materials. However, few papers report the use of this methodology in the extraction processes of Punica granatum. To evaluate an ultrasound-assisted extraction process to extract polyphenols from Punica granatum fruit