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1
Askari, Syed Hasan. "Synthesis and medium-dependent photochemistry of tetrahydro-1,4- Anthraquinones and Anthraquinols : structure-reactivity relationships from X-ray crystallography." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26954.
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Previous work from our laboratory has been concerned with investigating
the photochemical reactivity of tetrahydro-1,4-naphthalenedione and tetrahydronaphthoquinol systems, both in the solid state and in solution. The fascinating results obtained prompted us to extend the studies to the analogous tetrahydro-1,4-anthracenediones, tetrahydro-5,12-naphthacenediones and tetrahydroanthraquinol systems. Tetrahydro-1,4-anthracenedione is expected to undergo bis-enolization with extreme ease, and therefore its preparation requires mild and neutral conditions.
These compounds were prepared by Diels-Alder reaction between o-quinodimethane and p-benzoquinone and other p-substituted quinones o-Quinodimethane was generated in situ by sulphur dioxide extrusion from 3,6-dihydrobenzo[b]oxathiin-2-oxide.
The photochemistry of the tetrahydro-1,4-anthracenediones, tetra-hydro-5,12-naphthalenedione and tetrahydroanthraquinols has been investigated both in the solid state and solution. The effect of the solid state medium on the photoreactivity, compared to the solution, is significant; the nature and/or the number of the photoproducts formed in the solid state is generally different from the results obtained in solution. These differences have been explained on the basis of the crystal and molecular structures of the reactants. Special steric effects, which may impede the photochemical reactions in the solid state have been identified. The values of the geometric parameters (d, r and A) for hydrogen atom abstraction are found to be similar to those observed in earlier studies by Scheffer et al.
It has been found that the o-quinodimethane/2,3-dimethyl-l,4-naphthoquinone adduct affords, via β-hydrogen atom abstraction and closure of the resulting 1,3-biradical, a cyclopropanol. The cyclopro-panol itself undergoes photolysis initiated by a novel ring opening process. Irradiation of crystals of the adduct does not result in any cyclopropanol. The reasons for the non-reactivity of the Diels-Alder adduct in the solid state have been suggested to be due to the non-bonded steric interactions between the lattice neighbors as shown by the X-ray crystal structure.
The photorearrangement of one substrate, namely 2,3,4a,9a-tetra-methyl-4a,9a,9,10-tetrahydro-1,4-anthracenedione is found to be controlled
by the temperature, multiplicity, and phase of the reaction. By carrying out the reaction at or above room temperature or in the presence
of a sensitizer or in the crystalline state, the reaction can be forced in one direction. Lowering the photolysis temperature causes the formation of another product. The nature of the photoproduct is independent
of the temperature in the crystalline state. The results have been interpreted in terms of a required ring inversion which is needed for the formation of the low temperature photoproduct (see Scheme 44). The ring inversion is not allowed in the solid state.Science, Faculty of
Chemistry, Department of
Graduate
2
Samp, James Christian. "A comprehensive mechanism for anthraquinone mass transfer in alkaline pulping." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24767.
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Thesis (Ph.D.)--Chemical Engineering, Georgia Institute of Technology, 2008.Committee Chair: Dr. Jeff Empie; Committee Member: Dr. Bill Koros; Committee Member: Dr. Jim Frederick; Committee Member: Dr. Tom McDonough; Committee Member: Dr. Xin-Sheng Chai
3
Mitchell, Anthony Stewart, and mikewood@deakin edu au. "Synthetic studies towards anthraquinones." Deakin University. School of Biological and Chemical Sciences, 1994. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20051017.151445.
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The oxidation of substituted phenols with phenyliodonium diacetate in methanol was found to afford 2,4-cyclohexadienones, 2,5-cyclohexadienones or mixtures of isomers depending on the substrate being oxidized. A reaction mechanism was proposed for this oxidation which involved an intermediate aryloxenium ion. A strong correlation was observed between the experimentally determined product ratios and the results predicted by calculation of the LUMO coefficients of the proposed intermediates,
Annulation of these cyclohexadienones with the anion derived from cyanophthalide afforded substituted anthraquinones in high yields. The chemistry relating to the annulation of Michael acceptors with phthalide anions was comprehensively reviewed.
A mild selective method for the oxidation of hydroquinones to quinones using dibenzoyl peroxide and base is presented.
A general synthetic approach to C-glycosylanthraquinones was presented, based on the annulation of a C-glycosylcyclohexadienone with the anion derived from cyanophthalide, A suitable precursor to a C-glycosylcyclohexadienone, 2-(2,3,4,6-tetra-0-acetyl-|3-D-glucopyranosyl)benzyloxybenzene, was prepared via the reaction of benzoylbromoglucose with 2-benzyloxyphenylmagnesium bromide,
A group of molecules were prepared by a Marschalk reaction between /ewcoquinizarin and aldehydo-sugsrs. These compounds are potential bioreductive alkylating agents in which molecular simplicity can be achieved without overly sacrificing DNA binding ability.
4
Rabinowitz, Daniel Joshua. "Electrochemical Studies of Substituted Anthraquinones." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/chemistry_theses/15.
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Electrochemical potentials of a series of anthraquinone derivatives were studied in both aqueous solution and acetonitrile. The long term goal of this work was to find derivatives which could be reduced easily for studies of photoinduced electron transfer in DNA. Our immediate goal was to find the substitution group that gave the least negative redox potential value. Of all derivatives studied, the anthraquinone imides as a class had the least negative redox potentials, in the range of -0.600 to -0.550 V vs. SCE. One of the anthraquinones studied, one derivative (deoxyadenosine conjugated with an ethynyl linker to an anthraquinone with two ester substituents) was also in this range. A study of a series of anthraquinones conjugated with ethynyl and ethanyl linkers showed that the ethynyl linker was more effective than the ethanyl linker in lowering the redox potential of anthraquinone.
5
Spargo, P. L. "Biomimetic synthesis of polyketide anthraquinones." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383910.
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Zhang, Hai Long. "Study on anthraquinones from morinda officinalis." Thesis, University of Macau, 2009. http://umaclib3.umac.mo/record=b2158154.
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Moore, John Neville. "Time resolved spectroscopy of water-soluble anthraquinones." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/38109.
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Chigr, Mohamed. "Mise au point d'une synthèse régiosélective d'amino-anthraquinones et d'aza-anthraquinones par la réaction de Diels-Alder : activité antitumorale de quelques dérivés." Lyon 1, 1989. http://www.theses.fr/1989LYO1T034.
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Moroh, Jean-Luc Aboya. "Résistance bactérienne et phytomolécules antimicrobiennes issues de Morinda morindoides." Thesis, Brest, 2013. http://www.theses.fr/2013BRES0028/document.
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Nous assistons durant ces trente dernières années à une croissance de la fréquence d’apparition des bactéries résistantes aux antibiotiques. Face à la récurrence des infections difficiles à traiter dues à ces bactéries pathogènes multi-résistantes, le renforcement de l’arsenal des antimicrobiens fait partir des préoccupations majeures de santé publique. À ce titre, une approche ethno-pharmacologique a été initiée dans le cadre d’une coopération entre le laboratoire de pharmacodynamie biochimique (Université Félix Houphouët-Boigny, Côte d’Ivoire) et le laboratoire universitaire de biodiversité et d’écologie microbienne(Université de Bretagne Occidentale, France). Dans cette approche, les habitudes traditionnelles d’automédication par les plantes médicinales ont été exploitées pour identifier de nouvelles sources de composés antimicrobiens. Dans une première partie de cette présente étude, une investigation sur les résistances bactériennes en Côte d’Ivoire a montré non seulement une évolution de la fréquence d’apparition des bactéries résistantes aux antibiotiques dans le temps, mais aussi une évolution de ces souches résistantes vers des différents types de multi-résistances. Dans la seconde partie, Morinda morindoides, une plante médicinale ivoirienne, a suscité notre attention pour la recherche de substances antimicrobiennes. À partir de 18 extraits des différents organes de cette plante, des tests d’activité antimicrobienne ont permis de justifier son utilisation en médecine traditionnelle. L’extrait à l’acétonitrile de la racine qui affiche l’activité la plus intéressante a servi pour isoler et caractériser 12 phytomolécules antimicrobiennes dont une se distingue par sa structure chimique originale, la morindoïdine. En plus de leurs paramètres antimicrobiens, d’autres propriétés biologiques de ces substances ont été évaluées telles que, leur pouvoir antioxydant, leur cytotoxicité, leur activité hémolytique et leur cible moléculaire. Cette évaluation a révélé un mode d’action sans doute proche de celui des quinolonesWe are witnessing over these last thirty years a growing frequency of occurrence of antibiotic-resistant bacteria. This observation is coupled with a reduction in discovery of new antimicrobials. Given the recurrence of difficult to treat infections caused by these pathogens become multidrug resistant, strengthening the antimicrobial arsenal is one of the main public health concerns. To this end, an ethnopharmacological approach has been developed. Within the framework of cooperation between the laboratory of Biochemical pharmacodynamics (University of Cocody, Côte d'Ivoire) and the laboratory of microbial biodiversity and ecology (LUBEM EA 3882, University of Brest, France), traditional self-medication habits affecting more than 70% of the population of Cote d'Ivoire were analyzed to identify new sources of antimicrobial compounds. In the first part of this study, an investigation of bacterial resistance in Côte d'Ivoire has revealed not just an increase in the frequency of occurrence of antibiotic-resistant bacteria in time, but also an evolution of resistant strains toward different types of antibiotics. In the second part, Morinda morindoides, an Ivorian medicinal plant aroused our attention for the research of antimicrobial substances. From 18 extracts from different organs of this plant the antimicrobial activity tests were performed. The acetonitrile extract of the root which exhibit the most interesting activity was used to isolate and characterize 12 antimicrobial phytomolecules. One of these compounds exhibits an original chemical structure named morindoidine. In addition to their antimicrobial activity, other biological properties of these substances have been evaluated such as their antioxidant potency, their cytotoxicity, their hemolytic activity and their molecular target. This assessment revealed a mode of action probably close to that of quinolones
10
Martin, Philippe. "Synthèse de quinones polycycliques et d'analogues inhibiteurs potentiels de topoisomérases et de l'interleukine 1." Poitiers, 1997. http://www.theses.fr/1997POIT2298.
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Les quinones sont une famille de composes presentant souvent des activites biologiques remarquables (antibiotique, anticancereuse, antioxydante. . . ). C'est le cas notamment de la doxorubicine et de la daunorubicine qui sont des antitumoraux utilises cliniquement. Les quinones, mono ou polycycliques ont egalement un interet du point de vue chimique (par exemple, la ddq est un bon agent de deshydrogenation). Les benzoquinones, les naphtoquinones, les anthraquinones (comme la diacerheine, compose anti-arthrosique) et les anthracyclines (tetrahydronaphtacenequinones) sont les quinones les plus couramment etudiees. Par contre, les composes de type naphtacenequinones sont peu decrits dans la litterature, bien que certaines aient montre une activite biologique importante : ces composes possedent une capacite d'inhibition vis-a-vis des topoisomerases 1 et 2, enzymes essentielles a la replication de l'adn. Generalement, c'est la topoisomerase de type 2 qui est la cible des antitumoraux utilises cliniquement. Ce mode d'action presente cependant certaines limites : apparition d'une resistance multidrogue acquise et faible efficacite sur certains types de cancers (colon en particulier). Par ailleurs, la camptothecine (alcaloide) est une molecule possedant une bonne specificite vis-a-vis de la topoisomerase 1 qui a conduit recemment a la mise sur le marche de plusieurs analogues. Apres un rappel des proprietes et des mecanismes d'action des topoisomerases, la synthese de naphtacenequinones isolees recemment, en particulier la saintopine et uce 6, ainsi que le precurseur de ce dernier compose, la tetracenomycine d, a ete etudiee. Dans un second temps, la synthese d'analogues d'une anthraquinone, la diacerheine, utilisee pour le traitement de l'arthrose est decrite. Cet anti-inflammatoire, a l'activte tres prometteuse, presente cependant des effets indesirables que les analogues de synthese vises ne devraient pas posseder. Apres un bref rappel des mecanismes impliques dans l'arthrose, la preparation de nouvelles anthraquinones ainsi que des molecules de structure proche (xanthones) est reportee.
11
Fonteneau, Nadia. "Conception et synthèse d'inhibiteurs potentiels de l'interleukine 1 et de la cyclooxygénase pour le traitement de l'arthrose." Poitiers, 2000. http://www.theses.fr/2000POIT2302.
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L'arthrose, malgre les progres realises, est la deuxieme cause d'invalidite apres les affections cardio-vasculaires, devenant ainsi un probleme socio-economique. A l'heure actuelle, les medicaments de cette pathologie peuvent etre classes en deux categories : les ains, inhibiteurs preferentiels et selectifs de la cox-2 (cyclooxygenase), et les anti-arthrosiques d'action lente tel que la rheine. Dans ce memoire sont decrites la synthese et l'activite pharmacologique de deux familles de composes correspondants aux categories ci-dessus. Dans une premiere partie, une strategie de synthese originale de la rheine a ete developpee a partir d'une reaction cle de carbonylation d'un triflate catalysee par le palladium (0) est presentee. Cette methode permet egalement d'acceder a des analogues de type xanthone et flavone conservant les proprietes structurales caracteristiques de la rheine, a savoir, les fonctions acide, phenol et carbonyle chelate. La deuxieme partie concerne la conception et la synthese d'inhibiteurs preferentiels de la cox-2 a partir d'une etude de la relation structure-activite des composes actifs connus. Des tests biologiques (inhibition de la secretion de l'il-1, du tnf, de l'il 6) ont ete effectues sur ces deux familles de composes anti-arthrosiques. Deux d'entre eux presentent un potentiel pharmacologique interessant justifiant un developpement ulterieur.
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Giles, Yvonne. "Synthesis, DNA interactions and activation of novel cytotoxic anthraquinones." Thesis, De Montfort University, 1999. http://hdl.handle.net/2086/10751.
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Mitoxantrone is a dihydroxyanthracenedione derivative with significant clinical activity against advanced breast cancer, lymphoma and several types of leukaemia. However, as with all conventional anticancer agents, its non-specific nature results in dose-limiting systemic toxicity. The pharmacological (and toxicological) effects of mitoxantrone are thought to be mediated through its interaction with DNA and the DNA processing enzyme, topoisomerase II. Hence, an investigation of the DNA binding properties of mitoxantrone and related bis-substituted alkylaminoanthraquinones was undertaken with a view to developing agents with reduced toxicity to normal cells. DNA intercalation was evaluated using spectrophotometric and DNA thermal denaturation (Tm) techniques with calf thymus DNA. Overall, compounds that were hydroxylated at the 5 and 8 positions of the anthraquinone chromophore had increased DNA binding affinity compared to their non-hydroxylated analogues. The ~ Tms of mitoxantrone and its non-hydroxylated analogue ametantrone, were 26.4 °C and 21.5°C respectively. The affinity constants (K) for the chromophore-hydroxylated compounds were between 3.94 and 4.95 xl06M-1 while K values for their non-hydroxylated analogues were between 1.63 and 3.25 xl06M-l. For the di-N-oxide, AQ4N, intercalation was not detectable. The mono-N-oxide, AQ6N, showed modest DNA binding activity, with a ~Tm of7.0°C and an affinity constant of 3.64 Xl06M-l. Several of the alkylaminoanthraquinones were further investigated for their ability to inhibit decatenation of kDNA by topoisomerase II. Mitoxantrone and its analogues, AQ4 and AQ6, inhibited decatenation at concentrations ofO.75IlM, 1.51lM and 1.0llM respectively. In contrast, total inhibition of decatenation by the N-oxides, AQ4N and AQ6N, required concentrations of 50llM and 1 OIlM respectively. Hence modification of the terminal nitrogen on both alkylamino side chains to form a di-N-oxide resulted in a large decrease in DNA binding affinity and topoisomerase II inhibition. In view of the importance of the cationic alkyl amino side chains in intercalative binding and the enhanced ability of mitoxantrone to inhibit topoisomerase II, a series of acetalanthraquinones were synthesized. These compounds, referred to as YCG7 (1- substituted), YCG8 (l,4-bis-substituted), and YCG9 (l,5-bis-substituted), possessed dimethoxy groups in place of the alcohol groups of mitoxantrone, and were designed to be converted to their respective aldehydes, which should increase their cytotoxic activity due to their potential to form Schiffs bases with intracellular targets. The acetalanthraquinones were relatively poor DNA intercalators compared to the parent compound, ametantrone. The ~Tm values for YCG7, YCG8 and YCG9 were 3.6 °C, 14.2 °C and 15.7 °C respectively. The bathochromic shifts for the acetalanthraquinones in the presence of calf thymus DNA and 0.5M NaCl/0.008M Tris at a DNA:drug ratio of 10:1 were 1.4nm, 3.5nm and 3.6nm respectively for YCG7, YCG8 and YCG9 (ametantrone=12.2nm). Oxidative metabolism by NADPH-fortified mouse liver micro somes provided an effective route for the oxidation of acetalanthraquinones, producing two polar metabolites for YCG7 and three polar metabolites for both YCG8 and YCG9. The metabolites ofYCG7 and YCG8 were considerably more cytotoxic against the V79 Chinese hamster lung cell line than their respective acetalanthraquinones (4.4-fold for both compounds).YCG9 was found to be relatively cytotoxic per se, possibly due to its different mode of DNA binding, involving 'straddling' of the DNA helix. The increase in cytotoxicity of the metabolized products compared with the acetalanthraquinones supports the concept t?at they were conv.e~ed to their corresponding aldehydes. This leads the way to the deSIgn of acetal-contammg cytotoxic agents which can be selectively activated in tumours.
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Pullen, Graeme K. "2-substituted anthraquinones as photoinitiators of free radical polymerisation." Thesis, Manchester Metropolitan University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320492.
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Zembower, David Ewing. "The synthesis and structure-activity relationships of biologically active anthraquinones." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/26250.
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Boyce, James P. "Oxidative studies of emodin anthrone." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/27330.
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Soboyejo, N. O. "Disperse dyes derived from brominated 1,4-amino- or hydroxy-substituted anthraquinones." Thesis, University of Bradford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371497.
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Scott, Amanda Louise. "Synthesis and evaluation of free radical production of some substituted anthraquinones." Thesis, Open University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278004.
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Guyon, Frédérique. "Contribution à l'étude de la solidité à l'ozone de colorants anthraquinoniques acides." Mulhouse, 1998. http://www.theses.fr/1998MULH0521.
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L'ozone issu de la pollution est un facteur important de dégradation des colorants acides pour tapis. Le but de ce travail de doctorat est dans un premier temps d'apporter quelques éclaircissements sur ce phénomène et des solutions pour remédier à ce problème. La solidité à l'ozone des colorants acides dépend en premier lieu de leur structure chimique ; notre étude montrera qu'il y a une incompatibilité entre les solidités à la lumière et à l'ozone d'un colorant. On montrera ensuite que les colorants dont la mobilité sur la fibre est limitée, seront plus solides à l'ozone que ceux qui sont très mobiles (étude de colorants de taille croissante, puis de colorants diversement réactifs). La structure de la fibre est un élément qui influence la mobilité du colorant et de l'ozone et donc la solidité à l'ozone : plus on rend la fibre de polyamide ouverte, plus le déplacement du colorant est facilité, et sa dégradation à l'ozone plus aisée. On cherchera quelles seraient les solutions envisageables pour essayer de remédier à ce problème. La première idée sera d'appliquer des molécules suicides que l'ozone attaquera préférentiellement. Par analogie avec des solutions mises en oeuvre dans l'industrie du caoutchouc, on a synthétisé des molécules de la famille des hexahydrotriazines-thiones afin de tester leur potentiel antiozonant. Il se trouve que les résultats sont encourageants, bien que l'application de ces substances entraîne une baisse sensible de la solidité à la lumière. Une autre approche du problème consistera à essayer de fixer le colorant sur la fibre ; en effet, si la solidité à l'ozone d'un colorant dépend pour une grande part de son immobilité, on peut penser qu'un fixateur peut exercer une interaction positive. Les expériences faites prouveront que ce type de solution a le double avantage d'associer une bonne amélioration de la résistance à l'ozone sans entacher la solidité à la lumière, et une grande facilité de mise en oeuvre sur le plan de l'application.
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Audebert, Pierre. "Synthèse et caractérisation électrochimique de polypyrroles diversement substitués par des halogènés ou fonctionnalisés par des anthraquinones greffées." Grenoble 1, 1987. http://www.theses.fr/1987GRE10063.
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Synthese des polymeres conducteurs doues d'activite redox de la famille du polypyrrole. La synthese est basee sur la modification du pyrrole, soit par substitution par des atomes d'halogenes, soit par son greffage par des fonctions anthraquinones a l'azote, par l'intermediaire d'une chaine alkyle. Etude electrochimique et physicochimique des monomeres et des polymeres qui en resultent
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Morin, Emmanuel Grovel Olivier. "Aloe vera (L.) Burm.f . aspects pharmacologiques et cliniques /." [S.l.] : [s.n.], 2008. http://castore.univ-nantes.fr/castore/GetOAIRef?idDoc=47416.
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Biasca, Karyn L. "A study of the kinetics of delignification during the early stage of alkaline sulfite anthraquinone pulping." Diss., Available online, Georgia Institute of Technology, 1989:, 1989. http://etd.gatech.edu/theses/available/ipstetd-10/biasca%5Fkl.pdf.
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Lee, Young H. "Reductive biotransformation and decolorization of reactive anthraquinone dyes." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04062004-164708/unrestricted/lee%5Fyoung%5Fh%5F200312%5Fphd.pdf.
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Thesis (Ph. D.)--School of Electrical and Computer Engineering, Georgia Institute of Technology, 2004. Directed by Spyros G. Pavlostathis.Vita. Includes bibliographical references (leaves 332-345).
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Hobson, Debra Kay. "A natural source of anthraquinone dye intermediates : production and identification of microbial anthraquinones, an environmentally friendly method of producing dye intermediates, and their conversion to textile dyestuffs." Thesis, University of Bradford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.566824.
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An environmentally friendly route to anthraquinone dyes has been developed by exploiting the anthraquinone biochromophores produced by microorganisms. An extensive screen of biochromophore producers, including species of Pyrenophora, Trichoderma, Drechslera, Phoma and Curvularia, was undertaken. The biochromophores were extracted from the mycelia with acetone and characterised by means of TLC, HPLC, GLC, mass spectrometry and UV /vis spectrophotometry. Most of the organisms produced anthraquinones unsuitable for conversion to anthraquinone dyes/dye intermediates. Problems included the anthraquinones being produced only at low temperatures, being too complex for dye conversion, possessing substitutions in the P-position, or being produced association with fatty material or as mixtures and thus not of high enough purity for dye conversion. Two strains of Curvularia, C. lunata and C. ramosa produced cynodontin (1,4,5,8- tetrahydroxy-3-methylanthraquinone) of the required purity although initial yields were poor and associated with melanin. Strain selection and manipulation of the culture medium resulted in elimination of melanin and cynodontin yields of up to l.0g dm-3. The culture medium developed contains nitrate as the nitrogen source and 6% sucrose as the carbohydrate source. Zinc was shown to influence the balance between anthraquinone and melanin production whilst a cycle of l2h white light/l2h respite from light produced a lO fold increase in cynodontin yield. The optimum pH was pH 7.0 whilst a temperature of 28°C and aeration of around 4 dm3 minot with impeller speed of 400rpm was preferred. Cynodontin, once acceptable as a dyestuff in its own right, no longer has the washfastness required for modern detergents. However, as an intermediate, cynodontin requires only a few simple chemical steps to produce a blue biodye which is an analogue of Disperse Blue 7 and a green biodye which is an analogue of Acid Green 28. Both biodyes appear brighter than their chemically synthesised analogue and also possess slightly better fastness properties than the conventional dyes when applied to knitted polyamide.
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LATEF, ABDELKADER. "Etude de couches minces organiques et inorganiques susceptibles d'etre utilisees comme support d'enregistrement dans les disques optiques." Nantes, 1991. http://www.theses.fr/1991NANT2052.
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Ce travail est constitue de deux axes d'investigations essentiels, concernant des materiaux susceptibles d'applications dans le domaine des disques optiques. Le premier axe concernant l'etude des structures al/te. L'etude du contact al/te revele deux types de commutations electriques. Dans le cas des structures oxydees, c'est-a-dire protegees par une couche amorphe de se, la commutation est due a la formation d'un compose amorphe a l'interface. Les analyses esca montrent qu'il y a une diffusion progressive de l'o#2; aussi ces commutations doivent etre attribuees au compose amorphe teo#x. Le second type de commutation est du a la formation d'une couche d'alumine a l'interface al-te dans les structures exposees a l'air ambiant. Le deuxieme axe concerne l'obtention des couches minces de macromolecules organiques: l'anthraquinone (aq) et le dichloroanthraquinone (dcaq). Les couches minces de l'aq et de dcaq ont ete elaborees par sublimation sous vide, et caracterisees par diffraction de r. X. , absorption en i. R. Et visible, m. E. B. Et esca. Nous avons realise un sel complexe a transfert de charge par evaporations successives de deux couches superposees ag/dcaq. Les differentes techniques d'analyse montrent qu'il y a formation, apres recuit, d'un sel charge ag#+ dcaq. Des commutations electriques et des modifications de proprietes optiques ont ete obtenues dans des structures al/ag-dcaq/al. Les resultats sont interpretes en supposant un changement d'etats reversibles: sel complexe charge sel neutre
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Bouclier, Michèle. "Etude de la délignification par les solutions alcalines de sulfite de sodium : Application aux solutions alcalines de sulfite de sodium : Rôle de l'anthraquinone." Grenoble INPG, 1987. http://www.theses.fr/1987INPG0080.
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Etude de la délignification des végétaux par le sulfite en milieu alcalin, avec ou sans additif (anthraquinone en particulier). Les mécanismes de la délignification par les sulfites sont liés à l'adsorption des ions hydroxyle par les polysaccharides du bois. Le mode d'action de l'anthraquinone est précis. La structure morphologique des végétaux joue un rôle essentiel dans les processus de délignification et l'homogénéité des pâtes obtenues en dépend largement. Les résultats théoriques obtenus conduisent à proposer diverses applications des sulfites à la préparation des pâtes cellulosiques allant des pâtes chimico-thermomécaniques jusqu'aux pâtes blanchies
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Conrad, Catleen. "Bernhard-von-Cotta-Preis 2014: Reinigung und Charakterisierung von zwei Peroxidasen DypA und DypB aus Rhodococcus opacus 1CP." Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2016. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-211185.
Full textAbstract:
Das Bodenbakterium Rhodococcus opacus 1CP ist für sein Potenzial bekannt, organische Schadstoffe abzubauen. In dieser Studie lag der Fokus auf zwei Genprodukten, den farbstoffabbauenden Peroxidasen DypA und DypB, welche unter Anwendung von Klonierungs- und Expressionsstrategien mit hohen spezifischen Aktivitäten in reiner Form gewonnen werden konnten. Eine umfassende biochemische Analyse zeigte, dass beide Enzyme in der Lage sind, Farbstoffe unterschiedlicher Klassen, insbesondere jedoch, die als schwer abbaubar geltenden Anthraquinone, strukturell anzugreifen. Damit stellen sie lohnenswerte enzymatische Systeme zum Abbau toxischer Farbstoffe beispielsweise in industriellen Abwässern dar.
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Audebert, Pierre. "Synthèse et caractérisation électrochimique des polypyrroles diversement halogénés ou fonctionnalisés par des anthraquinones greffés." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376024468.
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Keppler, Melanie Dawn. "Strategies for increasing the stability of triple helical DNA." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302353.
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Umeweni, Chiko. "Synthesis of Internally Linked Carbazole DNA Oligomers: A Potential Monitor for Charge Transfer in DNA Studies." Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-07052005-161648/.
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Santos, RogÃrio Nunes dos. "Estudo quÃmico e farmacolÃgico de Senna reticulata." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2336.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoCoordenaÃÃo de AperfeiÃoamento de NÃvel Superior
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
Este trabalho descreve a investigaÃÃo fitoquÃmica de Senna reticulata Willd., (Leguminoseae), popularmente conhecida no Cearà como mangerioba grande, que tem uso na medicina popular no tratamento de doenÃas do fÃgado, reumatismo e cÃlicas menstruais. Os gÃneros Senna, Chamaecrista e Cassia foram investigados a partir de seus compostos antraquinÃnicos relatados na literatura atà os dias atuais, no interesse de se traÃar um perfil, que contribuÃsse com distinÃÃo quÃmica dos mesmos que atà alguns anos eram confundidos devido as suas grandes semelhanÃas botÃnicas. O tratamento cromatogrÃfico dos extratos etanÃlicos das folhas, caule e cascas de Senna reticulata possibilitou o isolamento e identificaÃÃo de seis antraquinonas, um flavonÃide e uma biantrona, a identificaÃÃo da mistura de dois triterpenos e dois fitoesterÃis glicosilados e em forma livre. Outra etapa do trabalho foi dedicada ao estudo farmacolÃgico de S. reticulata, que atravÃs de ensaios analisou o potencial antioxidante, a atividade antiparasitÃria, antibacteriana e anticonvulsivante dos extratos etanÃlicos das cascas, folhas, caule e substÃncias isoladas da referida espÃcie. As determinaÃÃes estruturais foram realizadas atravÃs de anÃlises espectroscÃpicas tais como: espectroscopia na regiÃo do infravermelho, de ressonÃncia magnÃtica nuclear de hidrogÃnio-1 e carbono-13, incluindo tÃcnicas bidimensionais do tipo 1H, 13C-COSY (nJCH, n = 1, 2 e 3) com detecÃÃo inversa, espectrometria de massas e comparaÃÃo com dados da literatura.
This work decrib the phytochemical investigations of Senna reticulata Willd., (Leguminoseae), popularly known as âmangerioba grandeâ in the Brazilian Northeastern. Medicinal plant used for of liver illnesses, for rheumatism and menstrual pains. The genera Senna, Chamaecrista and Cassia were investigated from to from your compounds anthraquinones told in the literature until the current days, in the interest of tracing a profile, that contributed with chemical distinction of the same ones that to some years they were confused due your great botanical similarities. The chemical studies of ethanol extract of leaves, trunk and trunk bark of S. reticulata, making possible the isolation and identification of six anthraquinones, one flavone and one bianthrone, a mixture of two triterpenes and two a mixture of glucosilated and free β-sitosterol and stigmasterol. Another stage of the work was dedicated to the study pharmacologic of S. reticulata, that through rehearsals analyzed the antioxidant potential, the activity antiparasite, antibacterials and anticonvulsant of the extracts ethanol the leaves, trunk and trunk bark and isolated substances of the referred species. The molecular structures of compounds were elucidated by spectroscopic methods such as infrared, mass epectrometry, and nuclear magnetic resonance including special pulse sequences such as 1H, 13C-COSY (nJCH, n = 1, 2 e 3) with inverse detection and comparison with literature data.
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Macedo, EdÃngelo Moura Siqueira. "Estudo quÃmico e farmacolÃgico de Senna martiana (Benth) Irw. & Barn." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8381.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoEste trabalho apresenta o estudo da composiÃÃo quÃmica de Senna martiana (Benth) Irw. e Barn. pertencente à famÃlia da Leguminoseae. Norteou-se este estudo para o conhecimento dos constituintes quÃmicos fixos das flores e das raÃzes da planta. O levantamento bibliogrÃfico revelou a ausÃncia de estudos quÃmicos, biolÃgicos ou farmacolÃgicos realizados com esta espÃcie, motivo pelo qual a planta foi selecionada para estudo. O isolamento e purificaÃÃo dos constituintes quÃmicos foi realizado utilizando tÃcnicas como cromatografia por adsorÃÃo em coluna aberta (CC); cromatografia em camada delgada (CCD), cromatografia lÃquida de alta eficiÃncia (CLAE) e na determinaÃÃo das estruturas, tÃcnicas espectroscÃpicas tais como: absorÃÃo na regiÃo do infravermelho (IV); RessonÃncia MagnÃtica Nuclear de HidrogÃnio (RMN1H); RessonÃncia MagnÃtica Nuclear de Carbono 13 (RMN 13C) uni e bidimensionais. Na avaliaÃÃo do potencial farmacolÃgico da espÃcie, foram realizados ensaios de atividade antioxidante (mÃtodo DPPH e DHBA), atividade antitumoral (mÃtodo MTT) e atividade tripanocida de quatro compostos isolados frente a enzima GAPDH. O estudo quÃmico de Senna martiana (Benth) Irw. e Barn., permitiu o isolamento do Ãcido triacontanÃico (Ãc. melÃssico), -sitosterol e estigmasterol, e aâamirina, de trÃs antraquinonas 1,8-diidroxiladas, crisofanol, fisciona e aloe-emodina alÃm de trÃs heterosÃdeos antrÃnicos, dois deles inÃditos na literatura.
This work presents the study of the chemical composition of Senna martiana (Benth) Irw. and Barn. (Leguminosea). This survey was performed to the knowledge of the chemical constituents of the flowers and roots. The isolation and purification of chemical constituents of the plant was accomplished using cromatographic techniques and in the determination of the structures espectroscopic techniques (IR), Nuclear Magnetic Resonance of Hydrogen (RMN 1H); Nuclear Magnetic Resonance of Carbon 13 (RMN 13C). In evaluating the pharmacological potential of this species, were assayed for antioxidant activity (DPPH and DHBA), antitumor activity (MTT assay) and trypanocidal activity of four isolated compounds against the enzyme GAPDH. Chemical studies and of Senna martÃana (Benth) I&B, allowed to the isolation of triacontanoic acid, -sitosterol, stigmasterol, - amyrin, -amyrin, three 1.8-dihydroxyanthraquinones, chrysophanol, physcion and aloe-emodin, in addition to three glycosides anthrones, two of them previously unpublished in the literature.
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Ma, Jiani, and 马佳妮. "Time-resolved spectroscopic studies of meta methyl activation reaction of selected benzophenone and anthraquinone derivatives." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/196012.
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Femtosecond time-resolved transient absorption (fs-TA), nanosecond time-resolved transient absorption (ns-TA), and nanosecond time-resolved resonance Raman spectroscopy (ns-TR3) methods were used to study the behaviors of the transient intermediates involved in the photophysical and photochemical processes of 3-methylbenzophenone (3-MeBP), 3-(hydroxymethyl)benzophenone (m-BPOH), and 2-(1-hydroxyethyl) 9,10-anthraquinone (2-HEAQ). A particular focus of this work was to study
the unusual meta methyl activation reactions of these compounds in
water-containing solutions. Density functional theory (DFT) calculations were
conducted to help make assignments of the observed experimental transient
species and to better understand the reaction mechanisms. First, the
photophysical and photochemical reactions of m-BPOH were investigated in
selected solvents. In acetonitrile (MeCN) the formation of the triplet state of
m-BPOH, (denoted as (m-BPOH)3 ), was detected via an intersystem crossing
(ISC). In 2-propanol (IPA), (m-BPOH)3 abstracted a hydrogen atom from the
solvent molecule to form an aryl ketyl radical. In an acidic mixed aqueous
solution at pH 2, the photoredox reaction appeared to be the predominant
reaction. In a more acidic aqueous solution with [H+] =1.0 M, the photoredox
reaction faced some competition from the overall photohydration reaction.
Second, the photophysical and photochemical reactions of 2-HEAQ in MeCN,
IPA, and neutral, acid and basic aqueous solutions were studied. The ISC
process of 2-HEAQ took place in MeCN with generation of the triplet excited
state species of 2-HEAQ, (2-HEAQ)3. In IPA solvent, (2-HEAQ)3 underwent a
hydrogen abstraction with the solvent. A photoredox reaction takes place via
an initial protonation process of the AQ group that is followed by deprotonation of the methylene C-H bond in aqueous solutions within a pH
range from 2 to 10. Under a stronger acidic aqueous condition with [H+] =1.0
M, the photohydration reaction becomes the major reaction. In strong basic
solutions (pH=12) only ISC was observed to take place. The unusual
photoredox reaction takes place via protonation of the carbonyl oxygen first
followed by deprotonation of the C-H bond in the side chain for both m-BPOH
and 2-HEAQ. The protonation of the excited carbonyl oxygen group has been
widely studied. On the other hand, the deprotonation of methylene C-H bond
is unusual. Therefore, this photoredox reaction for m-BPOH and 2-HEAQ is
termed as a meta methyl activation reaction. Third, the photophysical and
photochemical reactions of 3-MeBP were explored and compared to those of
4-methylbenzophenone (4-MeBP). This work found that 3-MeBP and 4-MeBP
exhibit similar behaviors with m-BPOH and 2-HEAQ in MeCN and IPA. In
MeCN, both 3-MeBP and 4-MeBP undergo an efficient ISC process producing
triplet excited state species, (3-MeBP)3 and (4-MeBP)3, respectively. In IPA,
the (3-MeBP)3 and (4-MeBP)3 intermediates were quenched by the hydrogen
abstraction reaction with the solvent. In acidic aqueous solutions (pH 2), the
protonated carbonyl oxygen species (3-MeBPH+)3 and (4-(MeBPH+)3 are
directly observed by fs-TA spectra. In the case of 4-MeBP, a photohydration is detected and the m-(4-MeBPH2O)3 and o-(4-MeBPH2O)1 species are
observed. In contrast, an unusual meta methyl activation reaction is observed
for 3-MeBP. In a stronger acid aqueous solution ([H+] =1.0 M) the meta
methyl activation reaction becomes the predominant reaction.published_or_final_version
Chemistry
Doctoral
Doctor of Philosophy
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Chen, Daidi. "Genetic studies on pleiotropic polyoxin resistant mutants of Bipolaris maydis." Kyoto University, 2018. http://hdl.handle.net/2433/232359.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第21158号
農博第2284号
新制||農||1060(附属図書館)
学位論文||H30||N5132(農学部図書室)
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 田中 千尋, 教授 本田 与一, 教授 宮川 恒
学位規則第4条第1項該当
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Supaka, Nuttapun. "Microbial decolorization of reactive dyes in an anaerobic : aerobic treatment system." Toulouse, INPT, 2003. http://www.theses.fr/2003INPT031G.
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Dans ce travail, des souches bactériennes isolées d'unitéss de traitement d'effluents de l'industrie textile, ont été étudiées pour leur aptitude à dégrader des colorants. Une culture mixte A5-S1 s'est révélée la plus efficace sur des colorants de type azoi͏̈que et anthraquinone. Les souches ont été identifiées, elles appartiennent au genre Paenibacillus. Les conditions expérimentales ont été définies, cuivre et nitrates se sont avérés inhibiteurs. L'anthraquinone-2,6-disulfonate accélère la décoloration par la souche A5. Cette quinone est réduite enzymatiquement en hydroquinone qui ensuite réduit chimiquement le colorant azoi͏̈que hors de la cellule. Il a été suggéré un rôle actif de la NADH quinone oxydoréductase membranaire dans cette réduction. Un réacteur à lit fluidisé mettant en oeuvre des cellules immobilisées dans des billes d'alginate a été utilisé en réacteur batch séquentiel : la décoloration s'effectue en anaérobiose suivie de l'abattement de la DCO en aérobiose.
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Bouammali, Boufelja. "Régiosélectivité de la réaction de Diels-Alder entre des 1-alcoxy (ou silyloxy)-2-aza-3- silyloxy-1,3-diènes et des naphtoquinones : recherche de l'activité antitumorale in vitro des 2-azaanthraquinone-3-ones." Lyon 1, 1991. http://www.theses.fr/1991LYO1T087.
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Güler, Gözde. "Part 1 controlling barriers to charge transfer in DNA : Part 2 : DNA-directed assembly of conducting oligomers /." Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26621.
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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009.Committee Chair: Schuster, Gary; Committee Member: Barry, Bridgette; Committee Member: Collard, David; Committee Member: Tolbert, Laren; Committee Member: Wartell, Roger. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Conrad, Catleen. "Bernhard-von-Cotta-Preis 2014: Reinigung und Charakterisierung von zwei Peroxidasen DypA und DypB aus Rhodococcus opacus 1CP." TU Bergakademie Freiberg, 2015. https://tubaf.qucosa.de/id/qucosa%3A23086.
Full textAbstract:
Das Bodenbakterium Rhodococcus opacus 1CP ist für sein Potenzial bekannt, organische Schadstoffe abzubauen. In dieser Studie lag der Fokus auf zwei Genprodukten, den farbstoffabbauenden Peroxidasen DypA und DypB, welche unter Anwendung von Klonierungs- und Expressionsstrategien mit hohen spezifischen Aktivitäten in reiner Form gewonnen werden konnten. Eine umfassende biochemische Analyse zeigte, dass beide Enzyme in der Lage sind, Farbstoffe unterschiedlicher Klassen, insbesondere jedoch, die als schwer abbaubar geltenden Anthraquinone, strukturell anzugreifen. Damit stellen sie lohnenswerte enzymatische Systeme zum Abbau toxischer Farbstoffe beispielsweise in industriellen Abwässern dar.
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Macedo, EdÃngelo Moura Siqueira. "Estudo QuÃmico de Plantas do Nordeste com atividade antioxidante: Senna martiana Benth (I. e B)." Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1558.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoNeste trabalho apresenta-se o estudo da composiÃÃo quÃmica de Senna martiana (Benth) Irw. e Barn. pertencente à famÃlia das Leguminosas (subfamÃlia Papilonoideae, sinÃnimo Fabaceae). Norteou-se este estudo para o conhecimento dos constituintes quÃmicos volÃteis das folhas e dos constituintes fixos das inflorescÃncias e do caule. Outro objeto de interesse foi a avaliaÃÃo da atividade antioxidante dos extratos hidroalcoÃlicos dos ÃrgÃos da planta acima citados. O levantamento bibliogrÃfico revelou a ausÃncia de estudos fitoquÃmicos, biolÃgicos ou farmacolÃgicos realizados com esta espÃcie, motivo pelo qual a planta foi selecionada para estudo. O estudo fitoquÃmico da planta foi realizado utilizando tÃcnicas como cromatografia por adsorÃÃo em coluna aberta (CC); cromatografia em camada delgada (CCD), e na determinaÃÃo das estruturas tÃcnicas espectroscÃpicas tais como: absorÃÃo na regiÃo do infravermelho (IV); RessonÃncia MagnÃtica Nuclear de HidrogÃnio (RMN 1H); RessonÃncia MagnÃtica Nuclear de Carbono 13 (RMN 13C) uni e bidimensionais. A extraÃÃo dos constituintes volÃteis foi realizada por hidrodestilaÃÃo usando-se forno de microondas como fonte de aquecimento e na avaliaÃÃo da atividade antioxidante utilizou-se como tÃcnicas de anÃlise, a capacidade seqÃestradora de radicais livres (mÃtodo DPPH) e a medida do potencial antioxidante (mÃtodo DHBA). O estudo do Ãleo fixo das sementes de Senna martiana, resultou na identificaÃÃo de quatorze Ãcidos graxos, sendo majoritÃrios, o Ãcido hexadecanÃico (37%) e o Ãcido 9,12-octadecanÃico (34,1%). O estudo cromatogrÃfico do extrato etanÃlico do caule de Senna martiana possibilitou o isolamento e identificaÃÃo do Ãcido triacontanÃico (Ãc. melÃssico), -sitosterol, de trÃs antraquinonas 1,8-dihidroxiladas, crisofanol, fisciona e aloe-emodina, cujas identidades quÃmicas foram confirmadas pela anÃlise de seus espectros e comparaÃÃo com os dados da literatura. Dentre os constituintes isolados obteve-se um heterosÃdeo de uma biantrona do crisofanol inÃdito na literatura.
This work presents the study of the chemical composition of Senna martiana (Benth) Irw. and Barn. belonging to the family of Leguminosas (subfamily Papilonoideae, synonym Fabaceae). this study was orientated for the volatile chemical representatives of the leaves knowledge and of the fixed representatives of the flowers and of the stem. Another object of interest was the evaluation of the antioxidant activity of the extracts hidroalcoÃlicos of the organs of the plant above mentioned. The bibliographical rising revealed the absence of studies phytochemistry, biological or pharmacolÃgics accomplished with this species, reason for which the plant was selected for study. The study phytochemistry of the plant was accomplished using techniques as cromatographic for adsorption in open column (CC); cromatographic in thin layer (CCD), and in the determination of the structures technical such espectroscopic as: absorption in the area of the red band (IV); Nuclear Magnetic Resonance of Hydrogen (RMN 1H); Nuclear Magnetic Resonance of Carbon 13 (RMN 13C) united and bidimensionais. The volatile representatives extraction was accomplished by hidrodestilacion being used microwave oven as heating source and in the evaluation of the antioxidant activity it was used as analysis techniques, the capacity kidnapper of free radicals (method DPPH) and the measure of the antioxidant potential (method DHBA). The study of the fixed oil of the seeds of Senna martiana, resulted in the identification of fourteen graxos acids, being majority, the hexadecanoic acid (37%) and the 9,12-octadecanoic acid (34,1%). The study cromatographic of the extract ethanolic of the stem of Senna martiana made possible the isolation and identification of the triacontanoic acid (melÃssico ac.), -sitosterol, of three anthraquinones 1,8-dihidroxylad, crysophanol, phyiscion and aloe-emodin, whose chemical identities were confirmed by the analysis of your spectra and comparison with the data of the literature. Among the isolated representatives it was obtained a heterosÃdeo of a bianthrone of the unpublished crysophanol in the literature.
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Carvalho, Vanessa Anastacio da Costa. "Estudos comportamentais da exposição à Senna occidentalis durante o período perinatal em ratos." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-03122013-162045/.
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A Senna occidentalis (sinônimo Cassia occidentalis) é uma planta amplamente utilizada pela população para fins medicinais, embora esteja associada a casos de intoxicação humana e animal. Por isso, além de ser considerada um problema de saúde pública, é tida também como uma planta tóxica de interesse pecuário. Sua toxicidade é atribuída à diantrona, uma quinolona, cujo mecanismo de ação tóxico se deve ao desacoplamento da fosforilação oxidativa mitocondrial, promovendo dano mitocondrial especialmente nos órgãos com maior demanda de oxigênio. O objetivo deste trabalho foi estudar, em ratos, os possíveis efeitos tóxicos causados pela exposição à Senna occidentalis durante o período de gestação. Para tanto, 36 fêmeas prenhes foram divididas em 5 grupos, que foram tratados do 6º ao 20º dia de gestação (período de organogênese e de desenvolvimento fetal) com 1%, 2%, 3% e 4% de sementes da planta na ração; o grupo controle recebeu a ração normal do laboratório. A escolha dessas concentrações foi embasada em estudos prévios de toxicidade subaguda em ratos, que mostraram efeito dose-dependente. Durante o período de gestação foram avaliados o peso corpóreo e o consumo de ração e água das fêmeas. Após o nascimento, os filhotes foram analisados quanto ao número de vivos e mortos e para a detecção de possíveis malformações externas. Foi avaliado também o desempenho reprodutivo e o comportamento materno das fêmeas. Com relação à prole, observou-se o seu desenvolvimento físico e de reflexos, bem como atividade geral no campo aberto, comportamento de brincar, labirinto em cruz elevado e labirinto em T. Os resultados do presente estudo mostraram diminuição no ganho de peso das ratas tratadas com 2%, 3% e 4% da planta na ração, além de diminuição no consumo de ração, prejuízo no desempenho reprodutivo e sinais de intoxicação em ratas do grupo de 4%. Ratas tratadas com 2% de S. occidentalis na ração apresentaram prejuízo no comportamento materno. Ainda, houve adiantamento para o aparecimento de pelos e erupção dos dentes incisivos em filhotes do grupo de 1%, bem como adiantamento para o desenvolvimento do reflexo de geotaxia negativa e para a perda do reflexo de preensão palmar em filhotes dos grupos de 3% e 1% respectivamente. Estes resultados indicam que a exposição à S. occidentalis durante a gestação causou toxicidade materna acompanhada de prejuízo no comportamento materno e alteração no desenvolvimento físico e reflexológico da prole destas ratas.The Senna occidentalis (synonym Cassia occidentalis) is a plant widely used by people for medicinal purposes, although it is associated with cases of human and animal poisoning. So, besides being considered a public health problem, it is also regarded as a toxic plant of livestock interest. Its toxicity is attributed to diantrone, a quinolone, whose mechanism of action is due to the toxic uncoupling of mitochondrial oxidative phosphorylation, promoting mitochondrial damage especially in organs with higher oxygen demand. The objective of this work was to study, in rats, the possible toxic effects caused by exposure to Senna occidentalis during the gestation period. For this purpose, 36 female rats were divided into 5 groups, which were treated from the 6th to the 20th day of gestation (period of organogenesis and fetal development) with 1%, 2%, 3% and 4% of plant seeds in the diet; the control group received normal chow lab. The choice of these concentrations was based on previous studies of subacute toxicity in rats, which showed dose-dependent effect. During the period of gestation were evaluated: body weight, feed intake and water consumption of females. After birth, pups were analyzed for the number of living and dead, and for the detection of possible external malformations. We also evaluated the reproductive performance and maternal behavior of females. With regard to offspring, it was observed their physical and reflexes development, their general activity in the open field, their play behavior and their behavior in elevated plus maze and T maze. The results of this study showed a decrease in body weight of dams treated with 2%, 3% and 4% of the plant in the diet, in addition to reduced feed intake, impaired reproductive performance and signs of poisoning in dams of group 4%. Dams treated with 2% of S. occidentalis in diet showed impaired maternal behavior. Still, there was an advance for the appearance of hair and for the eruption of incisors in pups from 1%, as well as an advance to the development of negative geotaxis reflex and to the loss of palmar grasp reflex in puppies of 3% and 1% groups respectively. These results indicate that exposure to S. occidentalis during pregnancy caused maternal toxicity accompanied by impairment in maternal behavior and change in reflexology and physical development of the offspring of these rats.
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Ganachaud, Chrystelle. "Laccases et colorants : vers des procédés écocompatibles." Aix-Marseille 3, 2008. http://www.theses.fr/2008AIX30033.
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Le projet SOPHIED (Sustainable Bioprocesses for European Colour Industries) s’inscrivait dans le cadre du 6ème PCRD et visait à développer des technologies innovantes et éco-compatibles pour aider et dynamiser l’industrie européenne des colorants. Dans le cadre de ce projet, le travail décrit dans ce manuscrit a consisté à développer de nouvelles voies de synthèses enzymatiques de colorants en utilisant la laccase comme catalyseur. Cette enzyme a été étudiée en vue de l’obtention de colorants anthraquinoniques (naturels ou non), indigoïdes, azoïques et phénoxazinoniques. Ainsi, un aperçu global des potentialités qu’offrent les laccases dans le domaine de la biosynthèse a été donnéSOPHIED project (Sustainable Bioprocesses for European Colour Industries) formed part of the FP6 and aimed to develop innovating and ecofriendly technologies to help and energize the european dye industry. Within this framework, the work described in this thesis consisted to develop new enzymatic ways for dye syntheses using laccase as catalyst. This enzyme has been studied in order to obtain anthraquinonic (natural or not), indigoid, azoic and phenoxazinonic dyes. A global view of laccase potentialities in biosynthesis has been shown
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Neella, C. K. "Synthetic studies toward the total synthesis of aflastatin A, bruguierol A and preparation of some 10-diarylmethylidene anthraquinones." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2008. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2672.
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Gasper, Susan M. "Spin selective reactivity of arylcations ; Part II: Anthraquinone oligonucleotide conjugates as probes of electron transfer in DNA." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/30533.
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Clément, Julia. "Les caractéristiques remarquables de la flore polynésienne. Un exemple type : Morinda citrifolia L." Paris 5, 2001. http://www.theses.fr/2001PA05P012.
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Abou-Elkhair, Reham A. I. "Synthesis of anthraquinone derivatives and their conjugates with 2'-deoxynucleosides as new probes for electron transfer studies in DNA." unrestricted, 2008. http://etd.gsu.edu/theses/available/etd-07182008-154942/.
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Thesis (Ph. D.)--Georgia State University, 2008.Title from file title page. Thomas L. Netzel, Dabney W. Dixon, committee co-chairs; David Boykin, Jerry Smith, committee members. Electronic text (250 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Nov. 20, 2008. Includes bibliographical references.
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Gouveia, Veloso Carlos Arthur. "Estudo Fitoquimico e atividades biologicas de varronia dardani e varronia leucocephala (Cordiaceae)." Electronic Thesis or Diss., La Rochelle, 2022. http://www.theses.fr/2022LAROS038.
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Le Brésil est un pays qui présente une vaste biodiversité, en particulier dans la région de la Caatinga, dans le Nordeste. Dans ce biome poussent des plantes de la famille des Cordiaceae, qui sont utilisées par les communautés locales pour le traitement de certaines maladies. C’est notamment le cas des espèces Varronia dardani et V.leucocephala, dont les infusions sont utilisées pour soulager les douleurs gastriques, les coliques menstruelles et l'arthrite. L'objectif de ce travail était de contribuer à la connaissance de ces espèces, en étudiant leurs propriétés phytochimiques et biologiques. Le matériel végétal a été collecté à Serra Branca-PB et Maturéia-PB et soumis à des processus d'extraction. L'extrait éthanolique brut de V. dardani (EEB-VD) a été soumis à la détermination des composés phénoliques totaux et à la quantification de l'acide rosmarinique, considéré comme l'un des marqueurs chimio taxonomiques de la famille des Cordiaceae. Un criblage a été effectué avec le EEB-VD pour évaluer son activité spasmolytique dans différents organes. L'activité antiproliférative des extraits et fractions de ces espèces a également été évaluée contre des cellules de mélanome humain (A2058). En utilisant des techniques de RMN, les composés isolés des espèces étudiées ont été identifiés. Le screening concernant l'activité dans le muscle lisse, a montré que l’extrait EEB-VD présente une activité spasmolytique non sélective dans différents tissus et pour différents agonistes testés, avec une puissance maximale sur l’utérus des rats. À partir de la fraction acétate d'éthyle du EEB-VD, il a été possible d 'isoler et d'identifier cinq flavonoïdes, dont trois aglycones (isosakuranetine, naringenine et rhamnocitrine) et deux glycosylés (astragaline et isoquercitrine), en plus de l'acide rosmarinique. En ce qui concerne le test d’activité antiprolifératif sur cellules de mélanomes, la fraction isopropanolique de l'extrait de racines de V. dardani s'est révélée la plus active, et c'est à partir de cette fraction qu'a été isolé une nouvelle molécule, la vardanone, la première hydroanthraquinone rapportée dans l'espèce V.dardani. Ce composé a été évalué dans une étude chimio-informatique, dans laquelle l'activité de son groupe d'isomères sur la lignée cellulaire A2058 a été analysée, par rapport aux témoins positifs que sont la dacarbazine et le vemurafenib, des médicaments utilisés dans le schéma thérapeutique actuel du mélanome. La deuxième espèce la plus active dans les tests d’inhibition de prolifération était V. leucocephala, à partir de laquelle il a été possible d'isoler une saikosaponine, déjà isolée précédemment dans l'espèce. Ainsi, les résultats chimiques et biologiques, obtenus dans ce travail, ont contribué à la connaissance du genre Varronia, de plus, l'étude a révélé de nouvelles possibilités de recherche sur ces espèces grâce à la découverte de nouveaux métabolites secondaires, principalement de la classe des quinonesBrazil is a country that presents a vast biodiversity, where we find the Caatinga region, represented by plants of the Cordiaceae family, which are employed by local communities as an alternative for the treatment of some diseases, as is the case with the species Varronia dardani and V. leucocephala, whose infusions are used for the relief of gastric pain, menstrual colic, and arthritis. Therefore, the aim of this work was to contribute to the knowledge about these species, by studying their phytochemical and biological properties. To this end, the plant material was collected in the locations of Serra Branca-PB and Maturéia-PB and submitted to extraction processes. The crude ethanolic extract of V. dardani (CEE-VD) was submitted to the determination of total phenolics and to a quantification of rosmarinic acid, considered one of the chemotaxonomic markers of the Cordiaceae family. A screening was performed with CEE-VD to evaluate its spasmolytic activity in various organs. In addition to this biological activity, the antiproliferative activity of the extracts and fractions of all species was evaluated against human melanoma cells (A2058). Using NMR techniques, the compounds isolated from the study species were identified. The screening concerning the activity in smooth muscle, showed that CEE-VD showed a non-selectiv eactivity in the different tissues and for the different agonists tested, showing highest potency in the uterus of rats. From the ethyl acetate fraction of the CEE-VD it was possible the isolation and identification of five flavonoids, being three aglycones (isosakuranetin, naringenin, and rhamnocitrin) and two glycosylated (astragalin andisoquercitrin), besides rosmarinic acid. Regarding the cytotoxic test, the isopropanolicfraction of the extract of roots from V. dardani proved to be more active, and from this fraction the compound vardanone was isolated, the first hydro anthraquinone reported I nV. dardani species. This compound, was used for a chemo informatics study, where its set of isomers was analyzed for activity in the A2058 cell line and some interactions between amino acid residues were observed, compared to the positive controls dacarbazine and vemurafenib, drugs used in current melanoma therapy. The second most active species in the cytotoxic tests was V. leucocephala, from which it was possible to isolate a saikosaponin, already isolated previously in the species. Thus, the chemical and biological results, obtained in this work, contributed to the knowledge about the genus Varronia, furthermore, the study revealed new possibilities for research on these species involving the search for new secondary metabolites, mainly of the class of quinones
O Brasil é um país que possui uma vasta biodiversidade, onde encontramos a região da Caatinga, representada por vegetais da família Cordiaceae, os quais são empregados pelas comunidades locais como uma alternativa para o tratamento de algumas doenças,como é o caso das espécies Varronia dardani e V. leucocephala, cujas infusões são utilizadas para o alívio das dores gástricas, cólica menstrual e artrite. Sendo assim, buscou-se contribuir para o conhecimento sobre essas espécies, mediante o estudo fitoquímico e biológico das mesmas. Para isso, o material vegetal foi coletado nos municípios de Serra Branca-PB e Maturéia-PB e submetidos a processos de extração. O extrato etanólico bruto de V. dardani (EEB-VD) foi submetido à determinação defenólicos totais e à uma quantificação do ácido rosmarínico, considerado um dos marcadores quimiotaxonômicos da família Cordiaceae. Foi realizada uma triagem com o EEB-VD para avaliar a sua atividade espasmolítica em diversos órgãos. Além dessaatividade biológica, foi avaliada a atividade antiproliferativa dos extratos e frações de todas as espécies frente às células de melanoma humano (A2058). Através de técnicas de RMN foram identificadas as substâncias isoladas das espécies do estudo. A triagem relativa à atividade no músculo liso, mostrou que o EEB-VD apresentou uma atividade não seletiva nos diferentes tecidos e para os diferentes agonistas testados, apresentando maior potência no útero de ratos. Da fração acetato de etila do EEB-VD foi possível o isolamento e identificação de cinco flavonoides, sendo três agliconas (isosakuranetina, naringenina e ramnocitrina) e dois glicosilados (astragalina e isoquercitrina), além do ácido rosmarínico. Com relação ao teste citotóxico, a fração isopropanólica do extrato das raízes de V. dardani se mostrou mais ativa, e desta fração foi isolada a vardanona, primeira hidroantraquinona relatada na espécie V. dardani. O composto VD-R-I, foi utilizado para um estudo de quimioinformática, onde o conjunto de isômeros dessa substância foi analisado quanto à atividade na linhagem celular A2058 e foram observadas algumas interações entre resíduos de aminoácidos, comparando com ocontrole positivo dacarbazina e vemurafenibe, drogas utilizadas na terapia atual do melanoma. A segunda espécie mais ativa nos testes citotóxicos foi a V. leucocephala, de onde foi possível isolar uma saikosaponina, já isolada ateriormente na espécie. Logo, osresultados químicos e biológicos, obtidos nesse trabalho, contribuíram para o conhecimento sobre o gênero Varronia, ainda assim, o estudo revelou novas possibilidades de pesquisas nessas espécies envolvendo a busca de novos metabólitossecundários, principalmente da classe das quinonas
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Tse, Sum Bui Jeanne Bernadette. "Interactions de l'alcool déshydrogénase de levure avec les colorants anthraquinones : modulation par des ions métalliques et un milieu à faible activité de l'eau." Compiègne, 1991. http://www.theses.fr/1991COMPD440.
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Ce travail concerne l'étude des interactions moléculaires de l'alcool déshydrogénase de levure avec des colorants anthraquinones notamment le Cibacron Bleu F3G-A et le Procion Bleu MX-R. Nous avons substitué les résidus chlorés des noyaux triaziniques de ces colorants par des groupements hydroxyl et nous avons montré l'importance de ces résidus chlorés en ce qui concerne l'inhibition de l'enzyme. Les effets de la présence d'ions Zn2+ exogène sur l'interaction protéine-colorant ont ensuite été étudies. Le Zn2+ seul s'avérait être plus inhibiteur que le Procion Bleu MX-R. De plus, ces interactions ternaires invoquant ion métallique, colorant, protéine sont fortement dépendantes de la nature du tampon. En dernier lieu, nous avons étudié l'effet d'un dépresseur de l'activité de l'eau, le sorbitol sur la cinétique et la stabilité de l'YADH en présence de colorants. L'affinité des colorants augmente avec la concentration en sorbitol. Nous avons aussi observé un effet coopératif sur la stabilisation de l'enzyme par les colorants sous forme -OH en présence de sorbitol. Ces résultats nous ont amenés à présenter une hypothèse pour expliquer cette stabilisation par la formation de ponts hydrogènes à des sites très spécifiques au site actif de la protéine.
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Borges, Warley de Souza. "Estudo de fungos endofíticos associados a plantas da família Asteraceae como fontes de metabólitos secundários e em processos de biotransformações." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/60/60138/tde-27082008-092456/.
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Fungos endofíticos constituem uma fonte promissora e ainda pouco explorada de novas substâncias potencialmente bioativas, que podem ter aplicações na medicina, agricultura e biologia química. Neste trabalho foram isolados cinco fungos endofíticos das folhas de Tithonia diversifolia, os quais foram cultivados em pequena escala e avaliados em diversos bioensaios. O fungo endofítico Phoma sorghina foi cultivado em escala ampliada, produzindo nove substâncias, sendo três derivados antraquinônicos inéditos na literatura. Três fungos endofíticos associados à Viguiera robusta foram estudados. De Colletotrichum gloeosporioides foram isoladas oito substâncias, sendo um derivado dicetopiperazínico e um derivado aminoaçúcar inéditos na literatura. Diaporthe phaesolorum produziu três derivados dicetopiperazinicos, um inédito na literatura. Chaetomium globosum produziu treze substâncias, sendo oito derivados azaphilônicos inéditos. Algumas linhagens endofíticas foram avaliadas em experimentos de biotransformação de três naftoquinonas e da 1-tetralona, catalisando reações de oxidação e redução. O fungo Diaphorte phaseolorum catalisou uma reação de metilação inédita na literatura de biotransformação.Endophytic fungi are a promising and untapped source of potential biologically active compounds that might be useful as therapeutic and agrochemical agents, or chemical biology tools. In this thesis five endophytic fungi were isolated from the leaves Tithonia diversifolia. All the strains have been cultivated in small scale and the extracts submitted to bioassays. The culture of the endophyte Phoma sorghina was scaled up, affording six known compounds and three novel anthraquinone derivatives. Three endophytes from Viguiera robusta have also been studied as sources of natural products. Colletotrichum gloeosporioides produced six known compounds, one novel aminosugar and one new diketopiperazine derivative. Diaporthe phaesolorum biosynthesized three diketopiperazine derivatives, one novel in the literature. Five known compounds and eight novel azaphilone derivatives were isolated from Chaetomium globosum. Some endophytic strains have been evaluated in biotransformation experiments of three naphthoquinones and 1-tetralone, catalyzing oxidation and reduction reactions. The endophyte Diaphorte phaseolorum catalyzed a novel methylation reaction in the biotransformation literature.
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Vidal, Marie-Hélène. "Influence d'un champ magnétique sur les recombinaisons géminées : étude de systèmes, anthraquinone-donneurs d'hydrogène." Paris 11, 1987. http://www.theses.fr/1987PA112265.
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Cette étude porte sur l'influence d'un champ magnétique sur l'orientation de réactions chimiques passant par l'intermédiaire d'une paire de radicaux libres à spins corrélés (radicaux en "cage"). Dans la première partie, nous avons exposé la théorie dite de la "paire de radicaux" permettant d'interpréter l'évolution de tels systèmes : les mécanismes de passage singulet-triplet et les différentes interactions à l'intérieur des paires ainsi que le traitement quantique de résolution du système. La technique utilisée pour cette étude est la photolyse laser nanoseconde (absorption) qui est décrite dans la deuxième partie. Dans la troisième partie, nous présentons les résultats expérimentaux obtenus sur les systèmes Anthraquinone (AQ) - Donneurs d'hydrogène :-nous montrons qu'il n'y a pas d'effet de champ sur de tels systèmes en solution homogène même à viscosité élevée, et donnons les spectres d'absorption des différents intermédiaires de réaction. -Par contre, nous mettons en évidence un effet de champ important lorsqu’AQ est confinée dans des micelles de SDS (HS), celles-ci jouant le rôle de donneur d'hydrogène. Nous obtenons le spectre d'absorption du radical semi-quinone AQH· en "cage" et proposons un mécanisme pour sa disparition vers les espèces AQH-S et AQH2. -L'addition du 9,10 Dihydroanthracene (DH2) à l'intérieur de la micelle, près de AQ permet, par la création de paires (AQH· DH·) peu mobiles d'augmenter l'effet de champ. -Des paires de radicaux immobilisées par une matrice protéique ont également été étudiées dans des centres réactionnels de bactéries photosynthétiques : dans ce cas, le champ de demi-effet est déplacé vers les champs faibles par rapport aux systèmes précédentsThis study is devoted to magnetic field effects on chemical reactions which involve a radical pair with correlated spins (radicals in a "cage"). In the first part, the radical pair theory is described: mechanisms of singlet-triplet mixing, the different interactions inside the pair and a quantum mechanical treatment of the radical pair. The details of the experimental method (nanosecond laser flash photolysis) are reported in the second part. In the third part are shown experimental results obtained on Anthraquinone (AQ) - Hydrogen donors systems:There is no magnetic field effect in homogeneous solution even at a high viscosity. The absotption spectra of the different reaction intermediates are obtained. However a magnetic field effect is put forward when AQ is introduced in SDS micelles which are hydrogen donors. The absorption spectrum of the AQH· semi-quinone radical in "cage" is shown and a mechanism is proposed for its disappearance to generate the AQH-S and AQH2 species. The addition of 9, 10 Dihydroanthracene (DH2) inside the micelle near AQ induces an increase of the magnetic field effect by creation of (AQH· DH·) pairs which diffuse slowly. Fixed radical pairs in a protein matrix were studied in reaction centers of photosynthetic bacteria: in that case, the half-effect field is shifted to low fields when compared to the precedingly described systems
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Zhou, Qiuqin [Verfasser], Helge B. [Gutachter] Bode, and Martin [Gutachter] Grininger. "Identification of selected secondary metabolites from Xenorhabdus and investigation on the biosynthesis of anthraquinones from Photorhabdus / Qiuqin Zhou. Gutachter: Helge B. Bode ; Martin Grininger." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2016. http://d-nb.info/1112601457/34.
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Yang, Hanbae. "Zero-Valent Iron Decolorization of the Anthraquinone Dye Reactive Blue 4 and Biodegradation Assessment of its Decolorization Products." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6920.
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Anthraquinone dyes constitute the second largest class of textile dyes, and are used extensively in the textile industry. A high fraction of the initial reactive dye mass used in the dyeing process remains in the spent dyebath. Reactive dyes are not readily removed by typical wastewater treatment processes and the high salt concentration typical of reactive dyeing further complicates the management of spent reactive dyebaths. Investigation of the reductive transformation of reactive anthraquinone dyes and their decolorization products has been very limited. Additionally, very limited research has been conducted on the decolorization of spent reactive dyebaths.
Research was conducted to investigate the key operational parameters of batch and continuous-flow ZVI decolorization of a reactive anthraquinone dye, Reactive Blue 4 (RB4), under anoxic conditions, as well as the potential for the biodegradation of its decolorization products in a halophilic culture under aerobic conditions. The effect of two operational parameters, such as mixing intensity and initial dye concentration, on the ZVI batch decolorization kinetics indicates that ZVI decolorization of RB4 is a surface-catalyzed, mass transfer-limited process. The high salt and base concentrations enhanced the rate of RB4 decolorization. Based on parameters such as porosity, hydraulic conductivity, pore water velocity, and dispersion coefficient, non-ideal transport characteristics were observed in a continuous-flow ZVI column. The results of a long-term continuous-flow ZVI decolorization kinetics demonstrated that continuous-flow ZVI decolorization is feasible. However, column porosity losses and a shift of reaction kinetics occur in long-term column operation. ZVI decolorization of RB4 was successfully described with a pseudo first-order or a site saturation model. Lastly, the RB4 decolorization products generated by ZVI treatment had no inhibitory effect on the halophilic culture. However, biodegradation and/or mineralization of RB4 decolorization products was not observed after a long-term incubation of the culture.
This research demonstrated the feasibility of ZVI decolorization of reactive anthraquinone dyes, which will help in the development of a continuous-flow, dyebath decolorization process and the possible reuse of the renovated dyebath in the dyeing operation. Such a system could lead to substantial reduction of water usage, as well as a decrease of salt and dye discharges.