DOCSLIB.ORG

Natural Phenol Polymers: Recent Advances in Food and Health Applications

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Natural Phenol Polymers: Recent Advances in Food and Health Applications antioxidants Review Natural Phenol Polymers: Recent Advances in Food and Health Applications Lucia Panzella and Alessandra Napolitano * Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia 4, Naples I-80126, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-081-674133 Academic Editor: Stanley Omaye Received: 17 March 2017; Accepted: 12 April 2017; Published: 14 April 2017 Abstract: Natural phenol polymers are widely represented in nature and include a variety of classes including tannins and lignins as the most prominent. Largely consumed foods are rich sources of phenol polymers, notably black foods traditionally used in East Asia, but other non-edible, easily accessible sources, e.g., seaweeds and wood, have been considered with increasing interest together with waste materials from agro-based industries, primarily grape pomace and other byproducts of fruit and coffee processing. Not in all cases were the main structural components of these materials identified because of their highly heterogeneous nature. The great beneficial effects of natural phenol-based polymers on human health and their potential in improving the quality of food were largely explored, and this review critically addresses the most interesting and innovative reports in the field of nutrition and biomedicine that have appeared in the last five years. Several in vivo human and animal trials supported the proposed use of these materials as food supplements and for amelioration of the health and production of livestock. Biocompatible and stable functional polymers prepared by peroxidase-catalyzed polymerization of natural phenols, as well as natural phenol polymers were exploited as conventional and green plastic additives in smart packaging and food-spoilage prevention applications. The potential of natural phenol polymers in regenerative biomedicine as additives of biomaterials to promote growth and differentiation of osteoblasts is also discussed. Keywords: tannins; lignins; grape pomace; spent coffee grounds; bioinspired phenolic polymers; black foods; food supplement; animal feed; food packaging; tissue engineering 1. Introduction Investigation of biomass as low cost sources of sustainable chemicals for direct exploitation or further to suitable transformations has become a main focus of academic and applied research over the last few years. Most of the vegetable sources currently investigated are rich in polymeric phenolic components that are amenable for several uses and applications. In the following part of this review, we will focus on selected classes of phenolic polymers with particular attention to those that can be obtained from abundant available sources by minimal processing. A considerable number of reports described the uses of such materials in different fields ranging from bioremediation [1] to material sciences, e.g., for preparation of phenolic resin, polyurethane, flocculants, gel, modified polymer materials or adhesives [2]. Apart from this, the great beneficial effects of natural phenol-based polymers on human health and their potential in improving the quality of food have been increasingly appreciated, and this work will critically review the most interesting and innovative reports in the field of nutrition and biomedicine that have appeared in the last five Antioxidants 2017, 6, 30; doi:10.3390/antiox6020030 www.mdpi.com/journal/antioxidants Antioxidants 2017, 6, 30 2 of 24 Antioxidants 2017, 6, 30 2 of 24 years.update Patents of those were applicatio excludedns that since have the maina potential aim of for this further review development is an update, ofbut those may applicationsnot be ready that for havea straightforward a potential for use further in industries. development, but may not be ready for a straightforward use in industries. After a short presentation of the main sources of the natural phenol polymers either dietary or not, withwith special special emphasis emphasis on on waste waste materials materials from fr agro-basedom agro-based industries, industries, polymers polymers obtained obtained through biomimeticthrough biomimetic procedures procedures from naturally-occurring from naturally phenol-occurring compounds phenol willcompounds be briefly will surveyed. be briefly The mainsurveyed. body The of the main review body will of addressthe review the will applications address ofthe phenol-based applications polymersof phenol of-based relevance polymers to food of andrelevance health. to food and health. 2. Main Sources of Natural Phenol Polymers 2.1. Dietary Sources Many largely consumed foods are rich sources of phenol polymers, most commonly tannins, traditionally categorized into thethe hydrolyzablehydrolyzable andand thethe condensedcondensed oror non-hydrolyzablenon-hydrolyzable classesclasses [[3].3]. One of the most investigated are those found in grapegrape skinskin andand seeds,seeds, mainlymainly polymericpolymeric proanthocyanidins belonging to the group of condensed tannins that can release monomeric phenols only upon depolymerization under acidic conditions (Figure1 1).). TheThe distributiondistribution andand levelslevels ofof thesethese tannins vary significantlysignificantly as a function of the grape variety and the degree of ripening and markedly affect thethe taste taste and and the the astringency astringency of the of winethe wine produced produced [4–8]. Of[4– the8]. sameOf the type same are tanninstype are occurring tannins inoccurring persimmon, in persimmon, a fruit largely a fruit consumed largely consumed in Japan [9 in]. Japan [9]. OH HO OH OH OH HO OH O O O HO O R =H, OH R1 1 O R =OH, gallate O 2 OH R2 O HO OH OH O OH OH O HO O OH OH O O O O HO O R1 Punicalagin R2 HO OH n HO OH OH OH OH OH OH OH HO O HO OH R1 OH HO R2 O OH O O Condensed tannins (proanthocyanidins) O O OH HO OH O OH O O HO HO OH OH O Punicalin Ellagitannins Figure 1. Structure of the main tannins found in grape, persimmon and pomegranate. Pomegranates are one of main highly valuable sources of ellagitannins that are also found in Pomegranates are one of main highly valuable sources of ellagitannins that are also found in other other fruits and nuts, e.g., strawberries, raspberries, blackberries, cloudberries, muscadine grapes, fruits and nuts, e.g., strawberries, raspberries, blackberries, cloudberries, muscadine grapes, almonds almonds and walnuts [10]. These tannins were formulated as hydrolyzable conjugates containing and walnuts [10]. These tannins were formulated as hydrolyzable conjugates containing one or more one or more hexahydroxydiphenoyl groups that esterify a sugar, usually glucose. The unique hexahydroxydiphenoyl groups that esterify a sugar, usually glucose. The unique gallagyl esters, gallagyl esters, punicalagin and punicalin, are the predominant ellagitannins of pomegranate punicalagin and punicalin, are the predominant ellagitannins of pomegranate (Figure1). They mainly (Figure 1). They mainly occur in the husk (pericarp) and peels (mesocarp) and are extracted into the juice upon commercial processing of the whole fruits. Analyses and quantitation of ellagitannins are Antioxidants 2017, 6, 30 3 of 24 Antioxidants 2017, 6, 30 3 of 24 occur in the husk (pericarp) and peels (mesocarp) and are extracted into the juice upon commercial particularlyprocessing ofdifficult the whole because fruits. they Analyses are only and partially quantitation solubilized of ellagitannins in the extraction are particularly solvent or difficultremain covalentlybecause they bound are only to cell partially walls and solubilized other macromolecules in the extraction of solvent the fruit or [11]. remain covalently bound to cell wallsThe and current other macromolecules burst of interest ofin thethe fruitblack [11 components]. of various foods or drinks of plant origin, includingThe current rice, tea, burst beans, of interest radish,in ginseng the black and components grapes, stems of various from the foods beneficial or drinks health of plant properties origin, attributedincluding to rice, the tea, pigments beans, as radish, evaluated ginseng in vitro and and grapes, in vivo stems studies from by the comparison beneficial with health the properties colorless varietiesattributed [12,13]. to the pigmentsActually, structural as evaluated studiesin vitro showedand in that, vivo thoughstudies all by appearing comparison black, with the the pigments colorless arevarieties very [different12,13]. Actually, in nature. structural Paradigmatic studies is showed the case that, of black though sesame all appearing seeds (Sesamum black, the indicum pigments L.), traditionallyare very different used in in Chinese nature. folk Paradigmatic medicine and is the as casefoodof in blackChina sesame and other seeds East (Sesamum Asian countries indicum andL.), largelytraditionally investigated used in for Chinese its potent folk medicine antioxidant and activity as food that in China is considered and other superior East Asian to countriesthat of white and sesamelargely investigatedseeds [14,15]. for The its black potent pigment antioxidant was activitypurified thatby hydrolytic is considered treatment superior of tothe that seeds of whiteafter removalsesame seedsof lipid [14 compone,15]. Thents, black but pigmentits insolubility was purified hampered by a hydrolytic detailed structural treatment analysis. of the seedsSolid state after spectroscopyremoval of lipid coupled components, to chemical but itsdegradation insolubility methodologies hampered a detailed and model structural studies analysis. indicated
Load more

Recommended publications
  • Tannins: Current Knowledge of Food Sources, Intake, Bioavailability and Biological Effects
    S310 DOI 10.1002/mnfr.200900039 Mol. Nutr. Food Res. 2009, 53, S310 – S329 Review Tannins: Current knowledge of food sources, intake, bioavailability and biological effects Jos Serrano1, Riitta Puupponen-Pimi2, Andreas Dauer3, Anna-Marja Aura2 and Fulgencio Saura-Calixto4 1 Universidad Complutense de Madrid, Depto. Nutricin y Bromatologa I, Madrid, Spain 2 VTT Technical Research Center of Finland 3 Hexal AG, Holzkirchen, Germany 4 Consejo Superior de Investigaciones Cientficas, Instituto del Frio, Depto. Metabolismo y Nutricin, Madrid, Spain Tannins are a unique group of phenolic metabolites with molecular weights between 500 and 30000 Da, which are widely distributed in almost all plant foods and beverages. Proanthocyanidins and hydrolysable tannins are the two major groups of these bioactive compounds, but complex tannins containing structural elements of both groups and specific tannins in marine brown algae have also been described. Most literature data on food tannins refer only to oligomeric compounds that are extracted with aqueous-organic solvents, but a significant number of non-extractable tannins are usu- ally not mentioned in the literature. The biological effects of tannins usually depend on their grade of polymerisation and solubility. Highly polymerised tannins exhibit low bioaccessibility in the small intestine and low fermentability by colonic microflora. This review summarises a new approach to analysis of extractable and non-extractable tannins, major food sources, and effects of storage and processing on tannin content and bioavailability. Biological properties such as antioxidant, antimicro- bial and antiviral effects are also described. In addition, the role of tannins in diabetes mellitus has been discussed. Keywords: Bioavailability / Diet / Hydrolysable tannins / Proanthocyanidins / Tannins / Received: November 27, 2007; revised: January 25, 2009; accepted: February 9, 2009 1 Introduction weight having the ability to complex strongly with carbohy- drates and proteins [9].
    [Show full text]
  • Inhibitory Activity of Synthesized Acetylated Procyanidin B1 Analogs Against Hela S3 Cells Proliferation
    Molecules 2014, 19, 1775-1785; doi:10.3390/molecules19021775 OPEN ACCESS molecules ISSN 1420-3049 www.mdpi.com/journal/molecules Article Inhibitory Activity of Synthesized Acetylated Procyanidin B1 Analogs against HeLa S3 Cells Proliferation Syuhei Okamoto 1, Sayaka Ishihara 1, Taisuke Okamoto 1, Syoma Doi 1, Kota Harui 1, Yusuke Higashino 1, Takashi Kawasaki 2, Noriyuki Nakajima 3,* and Akiko Saito 1,* 1 Graduate School of Engineering, Osaka Electro-communication University (OECU), 18-8 Hatsu-cho, Neyagawa-shi, Osaka 572-8530, Japan; E-Mails: [email protected] (S.O.); [email protected] (S.I.); [email protected] (T.O.); [email protected] (S.D.); [email protected] (K.H.); [email protected] (Y.H.) 2 Department of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan; E-Mail: [email protected] 3 Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan * Authors to whom correspondence should be addressed; E-Mails: [email protected] (N.N.); [email protected] (A.S.); Tel.: +81-766-56-7500 (N.N.); Fax: +81-766-56-2498 (N.N.); Tel.: +81-72-824-1131 (A.S.); Fax: +81-72-824-0014 (A.S.). Received: 19 November 2013; in revised form: 22 January 2014 / Accepted: 28 January 2014 / Published: 4 February 2014 Abstract: Proanthocyanidins, also known as condensed tannins and/or oligomeric flavonoids, occur in many edible plants and have various interesting biological activities. Previously, we reported a synthetic method for the preparation of various procyanidins in pure form and described their biological activities.
    [Show full text]
  • Meet Lycopene Prostate Cancer Is One of the Leading Causes of Cancer Death Among Men in the United States
    UCLA Nutrition Noteworthy Title Lycopene and Mr. Prostate: Best Friends Forever Permalink https://escholarship.org/uc/item/5ks510rw Journal Nutrition Noteworthy, 5(1) Author Simzar, Soheil Publication Date 2002 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Meet Lycopene Prostate cancer is one of the leading causes of cancer death among men in the United States. Dietary factors are considered an important risk factor for the development of prostate cancer in addition to age, genetic predisposition, environmental factors, and other lifestyle factors such as smoking. Recent studies have indicated that there is a direct correlation between the occurrence of prostate cancer and the consumption of tomatoes and tomato-based products. Lycopene, one of over 600 carotenoids, is one of the main carotenoids found in human plasma and it is responsible for the red pigment found in tomatoes and other foods such as watermelons and red grapefruits. It has been shown to be a very potent antioxidant, with oxygen-quenching ability greater than any other carotenoid. Recent research has indicated that its antioxidant effects help lower the risk of heart disease, atherosclerosis, and different types of cancer-especially prostate cancer. Lycopene's Characteristics Lycopene is on of approximately 600 known carotenoids. Carotenoids are red, yellow, and orange pigments which are widely distributed in nature and are especially abundant in yellow- orange fruits and vegetables and dark green, leafy vegetables. They absorb light in the 400- 500nm region which gives them a red/yellow color. Only green plants and certain microorganisms such as fungi and algae can synthesize these pigments.
    [Show full text]
  • BIOSYNTHESIS of PROANTHOCYANIDINS in BARLEY: GENETIC CONTROL of the CONVERSION of DIHYDROQUERCETIN to CATECHIN and PROCYANIDINS by KLAUS NYEGAARD KRISTIANSEN
    Carlsberg Res. Commun. Vol. 49, p. 503-524, 1984 BIOSYNTHESIS OF PROANTHOCYANIDINS IN BARLEY: GENETIC CONTROL OF THE CONVERSION OF DIHYDROQUERCETIN TO CATECHIN AND PROCYANIDINS by KLAUS NYEGAARD KRISTIANSEN Department of Physiology, Carlsberg Laboratory, Gamle Carlsberg Vej 10, DK-2500 Copenhagen Valby and Institute of Genetics, University of Copenhagen Oster Farimagsgade 2A, DK-1353 Copenhagen K Keywords: Flavonoid biosynthesis, leucocyanidin isomers, ant mutants, genetic control, high pressure liquid chromatography, 'H NMR, mass spectroscopy The conversion of dihydroquercetin to catechin and procyanidin was studied in maturing wild type barley (Hordeum vulgare L., cv. Nordal) seeds and proanthocyanidin free mutants blocked in four different genes, ant 13, ant 17. ant 18 and ant 19. In the wild type barley grown under controlled conditions, maximal rate of synthesis of catechin, procyanidin B3 and procyanidin C2 occurred 8-16 days after flowering. Dihydroquercetin was radioactively labelled by feeding ( 1-'4C)-acetate and (2-'4C)-acetate to flowerbuds of a petunia mutant accumulating this flavonoid. When fed to pericarp-testa tissue of wild type barley labelled catechin, procyanidin B3 and procyanidin C2 were synthesized establishing dihydroquercetin as a precursor of these compounds. In addition labelled 2,3-trans-3,4-cis-leucocyanidin was synthesized indicating that this compound is an intermediate. The leucocyanidin was identified by co-chromatography with an authentic standard prepared chemically by reduction ofdihydroquercetin with NaBH,. The major product of this reduction, however, was the 2,3-trans-3,4-trans-leuco- cyanidin. Only mutant ant 18-102 accumulated dihydroquercetin in the seeds. Feeding ('4C)-dihydroquercetin to pericarp-testa tissue from the mutants revealed that ant 17-139 was capable of synthesizing significant amounts of labelled catechin and procyanidin, whereas ant 13-101, ant 13-152, ant 18-102 and ant 19-109 synthesized none or only very small amounts of these compounds.
    [Show full text]
  • Metabolism in the Aging Retina and Retinal Degeneration
    Hindawi Oxidative Medicine and Cellular Longevity Volume 2020, Article ID 2692794, 12 pages https://doi.org/10.1155/2020/2692794 Review Article Implications of NAD+ Metabolism in the Aging Retina and Retinal Degeneration Ravirajsinh N. Jadeja ,1 Menaka C. Thounaojam ,2,3 Manuela Bartoli ,2,3 and Pamela M. Martin 1,2,3 1Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA 2Department of Ophthalmology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA 3James and Jean Culver Vision Discovery Institute and Medical College of Georgia at Augusta University, Augusta, GA, USA Correspondence should be addressed to Ravirajsinh N. Jadeja; [email protected] and Pamela M. Martin; [email protected] Received 8 February 2020; Accepted 17 April 2020; Published 11 May 2020 Academic Editor: Ryoji Nagai Copyright © 2020 Ravirajsinh N. Jadeja et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Nicotinamide adenine dinucleotide (NAD+) plays an important role in various key biological processes including energy metabolism, DNA repair, and gene expression. Accumulating clinical and experimental evidence highlights an age-dependent decline in NAD+ levels and its association with the development and progression of several age-related diseases. This supports the establishment of NAD+ as a critical regulator of aging and longevity and, relatedly, a promising therapeutic target to counter adverse events associated with the normal process of aging and/or the development and progression of age-related disease. Relative to the above, the metabolism of NAD+ has been the subject of numerous investigations in various cells, tissues, and organ systems; however, interestingly, studies of NAD+ metabolism in the retina and its relevance to the regulation of visual health and function are comparatively few.
    [Show full text]
  • Serum Retinal and Retinoic Acid Predict the Development of Type 2 Diabetes Mellitus in Korean Subjects with Impaired Fasting Glucose from the KCPS-II Cohort
    H OH metabolites OH Article Serum Retinal and Retinoic Acid Predict the Development of Type 2 Diabetes Mellitus in Korean Subjects with Impaired Fasting Glucose from the KCPS-II Cohort Youngmin Han 1 , Yeunsoo Yang 2 , Minjoo Kim 3 , Sun Ha Jee 2, Hye Jin Yoo 4,* and Jong Ho Lee 1,4,* 1 National Leading Research Laboratory of Clinical Nutrigenetics/Nutrigenomics, Department of Food and Nutrition, College of Human Ecology, Yonsei University, Seoul 03722, Korea; [email protected] 2 Institute for Health Promotion, Graduate School of Public Health, Yonsei University, Seoul 03722, Korea; [email protected] (Y.Y.); [email protected] (S.H.J.) 3 Department of Food and Nutrition, College of Life Science and Nano Technology, Hannam University, Daejeon 34430, Korea; [email protected] 4 Research Center for Silver Science, Institute of Symbiotic Life-TECH, Yonsei University, Seoul 03722, Korea * Correspondence: [email protected] (H.J.Y.); [email protected] (J.H.L.); Tel.: +82-2-364-9605 (H.J.Y.); +82-2-2123-3122 (J.H.L.); Fax: +82-2-364-9605 (H.J.Y. & J.H.L.) Abstract: We aimed to investigate whether retinal and retinoic acid (RA), which are newly discovered biomarkers from our previous research, reliably predict type 2 diabetes mellitus (T2DM) development in subjects with impaired fasting glucose (IFG). Among the Korean Cancer Prevention Study (KCPS)- II cohort, subjects were selected and matched by age and sex (IFG-IFG group, n = 100 vs. IFG-DM group, n = 100) for study 1. For real-world validation of two biomarkers (study 2), other participants in the KCPS-II cohort who had IFG at baseline (n = 500) were selected.
    [Show full text]
  • Proanthocyanidin Metabolism, a Mini Review
    Nutrition and Aging 2 (2014) 111–116 111 DOI 10.3233/NUA-140038 IOS Press Proanthocyanidin Metabolism, a mini review Y.Y. Choy and A.L. Waterhouse∗ Viticulture and Enology, University of California, Davis, CA, USA Abstract. There is emerging evidence suggesting that consumption of beverage and food rich in polyphenol may offer protective effects against various neurodegenerative, cardiovascular diseases and cancers. Proanthocyanidins (PACs) are one of the most abundant polyphenol in human diets, but also one of the least absorbed polyphenol mostly due to their size and structure com- plexity. PACs or condensed tannins are oligomers and polymers of monomeric unit flavan-3-ol (+)-catechin or (−)-epicatechin. To date, the absorption and metabolism of PACs are still remains largely unknown. The aim of this mini review was to highlight the absorption and metabolism of PACs, their effect in the gut and sample preparation for analysis. Ultimately, the potential bioactivities derived from the interaction between PACs metabolites and the gut microbiota warrants further investigation. Keywords: Proanthocyanidins, phenolic acids, metabolism, colon 1. Introduction derived subunits. PACs that consists exclusively of (−)-epicatechin, (+)-catechin units, are known as pro- Polyphenols are among the ubiquitous constituents cyanidins because only cyanidin is released in acid, of foods of plant origins and are widely distributed and comprised the largest class of PACs, while those throughout the plant kingdom. Polyphenols can be with gallocatechin units release delphinidin. The size categorized into different groups such as flavonoids, or molecular weight of PACs can be expressed as phenolic acids, stilbenes and lignans. The flavonoids mean degree of polymerization (mDP).
    [Show full text]
  • Vitamin a Derivatives As Treatment Options for Retinal Degenerative Diseases
    Nutrients 2013, 5, 2646-2666; doi:10.3390/nu5072646 OPEN ACCESS nutrients ISSN 2072-6643 www.mdpi.com/journal/nutrients Review Vitamin A Derivatives as Treatment Options for Retinal Degenerative Diseases Lindsay Perusek and Tadao Maeda * Department of Ophthalmology & Visual Sciences, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4965, USA; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +1-216-368-6103; Fax: +1-216-368-3171. Received: 7 May 2013; in revised form: 5 June 2013 / Accepted: 13 June 2013 / Published: 12 July 2013 Abstract: The visual cycle is a sequential enzymatic reaction for vitamin A, all-trans-retinol, occurring in the outer layer of the human retina and is essential for the maintenance of vision. The central source of retinol is derived from dietary intake of both retinol and pro-vitamin A carotenoids. A series of enzymatic reactions, located in both the photoreceptor outer segment and the retinal pigment epithelium, transform retinol into the visual chromophore 11-cis-retinal, regenerating visual pigments. Retina specific proteins carry out the majority of the visual cycle, and any significant interruption in this sequence of reactions is capable of causing varying degrees of blindness. Among these important proteins are Lecithin:retinol acyltransferase (LRAT) and retinal pigment epithelium-specific 65-kDa protein (RPE65) known to be responsible for esterification of retinol to all-trans-retinyl esters and isomerization of these esters to 11-cis-retinal, respectively. Deleterious mutations in these genes are identified in human retinal diseases that cause blindness, such as Leber congenital amaurosis (LCA) and retinitis pigmentosa (RP).
    [Show full text]
  • Antioxidants and Retinal Diseases
    antioxidants Editorial Antioxidants and Retinal Diseases María Miranda 1,* and Francisco Javier Romero 2,3 1 Departamento Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Cardenal Herrera-CEU, CEU Universities, 46315 Valencia, Spain 2 Facultad de Ciencias de la Salud, Universidad Europea de Valencia, 46010 Valencia, Spain; [email protected] 3 Hospital General de Requena, Generalitat Valenciana, 46340 Valencia, Spain * Correspondence: [email protected] Received: 26 November 2019; Accepted: 27 November 2019; Published: 29 November 2019 The retina is a thin membrane derived from the neuroectoderm, it is the physical morphological substrate in which the transformation of light energy into electrical impulses, that later will be led to the cerebral cortex, is performed. Due to its prosencephalic embryological origin, the retina is normally considered a specially differentiated part of the brain. It is a very complex tissue, formed by multiple cell layers and by several types of neuronal cells (ganglion, bipolar, horizontal, amacrine, and photoreceptor cells), microglia (macrophages), macroglia (Müller cells, astrocytes), and vascular cells (endothelium and pericytes). Under physiological conditions, the retina is characterized by a high oxygen consumption rate, intense exposition to pro-oxidizing agents (i.e., light) and a high content of polyunsaturated fatty acids (especially in the photoreceptor membranes). Therefore, retina is especially susceptible to oxidative stress [1–3]. Oxidative stress is defined as the imbalance between the generation and elimination of reactive oxygen species (ROS) and it results from either excessive ROS or an impaired antioxidant system. To cope with ROS increase, the retina has evolved different antioxidants defenses such as vitamin E, ascorbate, catalase, glutathione (GSH), glutathione-peroxidase, and glutathione-transferases [3].
    [Show full text]
  • Impaired Retinal Function and Vitamin a Availability in Mice Lacking Retinol-Binding Protein
    The EMBO Journal Vol.18 No.17 pp.4633–4644, 1999 Impaired retinal function and vitamin A availability in mice lacking retinol-binding protein Loredana Quadro1,2, William S.Blaner3, (Morris-Kay and Sokolova, 1996; Napoli, 1996). With the Daniel J.Salchow4, Silke Vogel3, exception of vision, the all-trans- and 9-cis-isomers of Roseann Piantedosi3, Peter Gouras4, retinoic acid are the active retinoid forms needed to Sarah Freeman4, Maria P.Cosma2, support retinoid-dependent processes. Retinoic acid Vittorio Colantuoni2,5,6 and isomers regulate gene expression by binding to specific Max E.Gottesman1,6 nuclear receptors, the retinoic acid receptors (RARs) and retinoid X receptors (RXRs), that function as ligand- 1Institute of Cancer Research, 3Department of Medicine and dependent transcription factors (Chen and Evans, 1995; 4Department of Ophthalmology, Columbia University, College of Kurokawa et al., 1995; Leblanc and Stunnenberg, 1995; Physicians and Surgeons, New York, NY 10032, USA and Mangelsdorf et al., 1995; Pfahl and Chytil, 1996). Expres- 2Department of Biochemistry and Medical Biotechnologies, University of Naples, Via Pansini 5, 80131 Naples, Italy sion of .300 genes is influenced by retinoic acid availability (Gudas et al., 1994; Clagett-Dame and Plum, 1997). The 5Present address: Faculty of Biological Sciences, University of Sannio, 82100 Benevento, Italy retinoid used in the visual cycle is 11-cis-retinal (Wald, 1968), which forms a Schiff’s base with opsin in photo- 6Corresponding authors e-mail: [email protected] or [email protected] receptors to generate rhodopsin, the visual pigment. When excited by light, 11-cis-retinal isomerizes to all-trans- Retinol-binding protein (RBP) is the sole specific trans- retinal.
    [Show full text]
  • Safety Assessment of Punica Granatum (Pomegranate)-Derived Ingredients As Used in Cosmetics
    Safety Assessment of Punica granatum (Pomegranate)-Derived Ingredients as Used in Cosmetics Status: Draft Final Report for Panel Review Release Date: May 15, 2020 Panel Meeting Date: June 8-9, 2020 The Expert Panel for Cosmetic Ingredient Safety members are: Chair, Wilma F. Bergfeld, M.D., F.A.C.P.; Donald V. Belsito, M.D.; Curtis D. Klaassen, Ph.D.; Daniel C. Liebler, Ph.D.; James G. Marks, Jr., M.D.; Lisa A. Peterson, Ph.D.; Ronald C. Shank, Ph.D.; Thomas J. Slaga, Ph.D.; and Paul W. Snyder, D.V.M., Ph.D. The Cosmetic Ingredient Review (CIR) Executive Director is Bart Heldreth, Ph.D. This safety assessment was prepared by Christina L. Burnett, Senior Scientific Analyst/Writer, CIR. © Cosmetic Ingredient Review 1620 L St NW, Suite 1200 ◊ Washington, DC 20036-4702 ◊ ph 202.331.0651 ◊fax 202.331.0088 ◊ [email protected] Distributed for Comment Only -- Do Not Cite or Quote Commitment & Credibility since 1976 Memorandum To: Expert Panel for Cosmetic Ingredient Safety Members and Liaisons From: Christina L. Burnett, Senior Scientific Writer/Analyst , CIR Date: May 15, 2020 Subject: Draft Final Safety Assessment on Punica granatum (Pomegranate)-Derived Ingredients Enclosed is the Draft Final Report of the Safety Assessment of Punica granatum (Pomegranate)-Derived Ingredients as Used in Cosmetics. (It is identified as pomegr062020rep in the pdf document.) At the December meeting, the Panel issued a Revised Tentative Report with the conclusion that the following 8 ingredients are safe in the present practices of use and concentration described
    [Show full text]
  • USDA Database for the Proanthocyanidin Content of Selected Foods
    USDA Database for the Proanthocyanidin Content of Selected Foods Release 2 Prepared by Seema Bhagwat and David Haytowitz Nutrient Data Laboratory Beltsville Human Nutrition Research Center Agricultural Research Service U.S. Department of Agriculture September 2015 Slightly Revised December 2015 U.S. Department of Agriculture Agricultural Research Service Beltsville Human Nutrition Research Center Nutrient Data Laboratory 10300 Baltimore Avenue Building 005, Room 107, BARC-West Beltsville, Maryland 20705 Tel. 301-504-0630, FAX: 301-504-0632 E-Mail: [email protected] Web site: http://www.ars.usda.gov/nutrientdata/flav Table of Contents Release History ............................................................................................................. i Suggested Citation: ....................................................................................................... i Acknowledgements ...................................................................................................... ii Documentation ................................................................................................................ 1 Changes in the update of the proanthocyanidins database ......................................... 1 Data Sources ............................................................................................................... 1 Data Management ....................................................................................................... 2 Data Quality Evaluation...............................................................................................
    [Show full text]