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Fresh tannic acid (5%) (FTA), heated to 121C for 15 min (PTA), and the combination of FTA and phosphates (FPH) were vacuum tumbled with catfish fillets and compared to water tumbled fillets (CTL). Fillets treated with FTA or PTA had higher whiteness whereas all treated fillets had higher chroma values than CTL, resulting in a deeper yellow color fillet. Microbial shelf life (CTL, log CFU/g, APC) of FTA and PTA treated fillets was extended by two days, to11.8 d at 4C, but FPH fillets did not reach over 5 log CFU/g for 15 d of storage. Fat from FTA and PTA treated fillets had induction points (IP) of 4.0 and 3.4 h, respectively, whereas FPH and CTL samples had IP of 1.4 and 2.4 h. Thus, FPH seems to be the best antimicrobial treatment and FTA/PTA, the best antioxidant treatment.

Abstract The effect of tannic acid (TA), gallic acid (GA), propyl gallate (PA) and ellagic acid (EA) on DNA damage in human lymphocytes induced by food mutagens, 3-amino-1-methyl-5 H-pyrido (4,3-b)indole (Trp-P-2) and 2-amino-1-methyl-6-phenylimadazo (4,5-b)pyridine (PhIP), and/or H2O2 was evaluated using single-cell electrophoresis (comet assay). The toxicity of these tested compounds on lymphocytes was not found. These compounds did not cause DNA damage at lower concentration of 0.1-10 µg/ml. At a concentration of 100 µg/ml, TA and GA exhibited slight DNA damage, whereas PA and EA showed no DNA damage. TA and its related compounds decreased the DNA damage induced by Trp-P-2 or PhIP at a concentration of 0.1-10 µg/ml. Moreover, the inhibition of H2O2-induced DNA damage increased with increasing concentrations up to 10 µg/ml. DNA repair enzymes, endonuclease III (Endo III) and formamidopyrimidine-DNA glycoslase (FPG) were used to examine the levels of oxidised pyrimidines and purines in DNA damage induced by H2O2, respectively. All the compounds at 10 µg/ml can reduce the level of FPG sensitive sites. However, only EA inhibited the formation of EndoIII sensitive sites. The results indicate that these compounds can enhance lymphocyte resistance towards DNA damage induced by food mutagens or H2O2. Keywords: Tannic acid; Human lymphocyte; Comet assay; Hydrogen peroxide

There is great interest in miniaturized analytical systems for life science research, the clinical environment, drug discovery, biotechnology, quality control, and environmental monitoring and numerous articles have been written which predict the success of microfluidic based systems. It was demonstrated in this work that a microfluidic flow system could be quickly and easily manufactured in a research lab environment without the need for clean room facilities. The microfluidic device was created using polymethylmethacrylate, a CO2 laser and a standard oven. The device was designed, manufactured and ready for use within three hours. This work also investigated a chemiluminescent system which was intended for use in protease assays in the microfluidic device. This work also focused on the use of photoinitiated polymer monoliths, with immobilized tannic acid, as protein preconcentrators. The function of the monolithic devices was demonstrated by pumping low concentration solutions of BSA BODIPY® FL through the monolith. Both loading and elution were done using pressure. It was shown that BSA could be concentrated on and successfully eluted from the monolith. The elution volume for a 125 nl monolith was found to be 4 μl. Therefore an injection of a 60 μl sample of 1 x 10⁻⁹M BSA BODIPY ® FL gave rise to a concentration factor of 15. The pH optimum for the binding of BSA BODIPY ® FL was found to be pH 8.0 and the loading capacity of the tannic acid monolith was found to be 0.6 mg.ml⁻¹.

Devido à grande importância que o gênero Eucalyptus apresenta, cada vez mais estudos relacionados à otimização da propagação de espécies do gênero vêm sendo conduzidos. Os principais entraves estão relacionados à sua clonagem e a recalcitrância que algumas espécies apresentam ao enraizamento e, por essa razão, o presente trabalho teve como objetivo avaliar o uso de bioestimulantes na mini e microestaquia de Eucalyptus spp. O presente trabalho se preocupou com o desenvolvimento de protocolos que não alteram excessivamente a prática empregada pelas empresas silviculturais. Para tanto, o trabalho foi dividido em 4 partes, sendo a primeira composta por uma revisão sobre enraizamento (item 2), visando elucidar todos os principais fatores que podem influenciar neste evento morfogênico. A partir desta revisão, se iniciaram estudos práticos com espécies e híbridos do gênero. O primeiro estudo (item 3) baseou-se na avaliação da morfofisiologia de miniestacas de três espécies de eucalipto (E. urograndis, E. benthamii e E. urophylla) em contato com AIB em pó e subsequente aplicação de tratamentos com bioestimulantes (ácido tânico e Algaren BZn®) utilizados de forma isolada e/ou em associação diretamente na base das miniestacas. O segundo estudo (item 4) avaliou a atuação destes mesmos tratamentos com bioestimulantes, em microcepas de Eucalyptus urograndis em fase de alongamento in vitro das brotações e sua posterior aclimatização. Por fim, o terceiro estudo (item 5) foi baseado na utilização dos tratamentos com bioestimulantes em microestacas de E. urophylla em fase de aclimatização em miniestufas, sendo os bioestimulantes aplicados na base das microestacas e na base das miniestufas (diretamente na bandeja). Em todos os experimentos foram coletados dados referentes aos parâmetros morfofisiológicos e, observou-se no primeiro e segundo experimento, que o ácido tânico na concentração de 250mg/L, foi o melhor tratamento empregado. Já, para o terceiro experimento, o Algaren BZn® na concentração de 1ml/L, apresentou resultados mais favoráveis. De acordo com as análises histológicas da rizogênese para todos os experimentos, verificou-se que as raízes adventícias desenvolvidas apresentaram origem cambial e conexão direta com o sistema vascular da parte aérea, indicando serem funcionais. O que permitiu constatar que, de forma geral, a adição de bioestimulantes otimizou a produção de mudas clonais de Eucalyptus. / According to the great importance that Eucalyptus genus presents, more studies are related to genus species propagation optimization have been conducted. Being the rooting recalcitrance that some species presents the main obstacle related to its cloning, this work had the aim to evaluate the biostimulants use in mini and microcuttings rooting process of Eucalyptus spp. For this, the present work was concerned with the protocols development that does not excessively alter the practice employed by silvicultural business. For this, the work was divided into 4 parts, the first have a rooting review (item 2), in order to elucidate all the main factors that may influence this morphogenic event. From this review, practical studies with species and hybrids of the genus were started. The first study (item 3) was based on the minicuttings morphology evaluation of the three eucalyptus species (E. urograndis, E. benthamii and E. urophylla) in contact with IBA in talc and the subsequent application of biostimulant treatments (tannic acid and Algaren BZn®) used in isolation and/or in combination directly on minicuttings base. The second study (item 4) evaluated the performance of these same treatments with biostimulants in E. urograndis microcuttings on the shoots elongation stage in vitro and their subsequent acclimatization. Finally, the third study (item 5) was based on the biostimulant treatments use in E. urophylla microcuttings in acclimatization phase in ministuff. The biostimulants were applied at microcuttings base and at ministuff base (directly on the trays). In all experiments, data regarding morphophysiological parameters were collected and it was observed in the first and second experiments that tannic acid at 250mg/L concentration was the best treatment used. For the third experiment, the Algaren BZn® in the concentration of 1 ml/L, presented more favorable results. According to the rhizogenesis histological analyzes for all the experiments, it was verified that the adventitious roots developed presented cambial origin and had a direct vascular connection with the aerial part, indicating its functionality. This showed that, in general, the biostimulants addition optimized the production of clonal Eucalyptus seedlings.

A estabilidade oxidativa é uma das mais relevantes propriedades que atestam a qualidade de um biodiesel. Esse fato pode comprometer a armazenagem e a sua utilização como combustível e para prevenir esta oxidação, faz-se necessário o uso de compostos que demonstrem eficiência frente ao processo oxidativo em biodiesel. Assim sendo, o presente trabalho teve como objetivo geral avaliar o efeito do Ácido Tânico (AT) e do Líquido extraído da Castanha do Caju (Anacardium occidentale L.) (LCC) como antioxidante para biodiesel, analisando as características gerais da oxidação. Para tanto, foi utilizada uma metodologia onde o estudo da estabilidade do biodiesel foi realizado por meio do Rancimat, termogravimetria, espectrofotometria e análises de acidez. Por meio da análise no Rancimat, constatou-se que todos os biodieseis aditivados apresentaram um aumento do PI (período de indução), ou seja, um aumento da estabilidade oxidativa, de forma progressiva com o aumento da adição do antioxidante. A avaliação termogravimétrica (TGA) empregada demonstrou que o LCC técnico apresentou uma maior temperatura inicial e menor temperatura final de decomposição quando comparado com os demais antioxidantes testados. Os resultados dos testes de acidez e espectrofotometria na armazenagem em estufa e prolongado, com todos os antioxidantes testados, não mostraram aumento significativo da oxidação devido ao tipo de teste empregado, que buscou reproduzir as condições reais de armazenagem. Vale ressaltar que os resultados encontrados nesta pesquisa atendem aos parâmetros de qualidade exigidos pelo órgão regulador dos biocombustíveis, a ANP. / Oxidative stability is one of the most important properties that attest to the quality of a biodiesel. This fact can affect the storage and their use as fuel and to prevent this oxidation, it is necessary the use of compounds that show efficacy against oxidative process into biodiesel. Thus, the present work had as general objective to evaluate the effect of Tannic Acid (TA) and the liquid extracted from the Cashew Nut (Anacardium occidentale L.) (LCC) as antioxidant for biodiesel, analyzing the General characteristics of oxidation. To this end, we used a methodology where the study of the stability of biodiesel was performed by means of Rancimat, Thermogravimetry, spectrophotometry and the analysis of acidity. By means of Rancimat analysis, it was found that all additives biodieseis showed an increase of PI (induction period), an increase of oxidative stability, progressively increasing the addition of antioxidant. The thermogravimetric maid evaluation showed that the LCC a higher initial temperature presented technical and minor final temperature of decomposition when compared with other antioxidants tested. The results of the tests of acidity and spectrophotometry in the kiln and prolonged storage, with all the antioxidants tested, showed no significant increase in oxidation due to the type of test used, which sought to reproduce the actual conditions of storage. It is worth noting that the results found in this research meet the quality parameters required by the regulator of biofuels, the ANP.

ABSTRACT PRODUCTION OF TANNASE BY ASPERGILLUS NIGER &Ouml / zt&uuml / rk, Alev Deniz M.S., Department of Chemical Engineering Supervisor: Prof. Dr. Ufuk Bakir Co-Supervisor: Prof. Dr. B. Z&uuml / mr&uuml / t &Ouml / gel August 2006, 90 pages In this study, a filamentous fungus, Aspergillus niger was evaluated in terms of extracellular tannase production. The effect of tannic acid, glucose and nitrogen sources on tannase and biomass productions was investigated and their concentrations were optimized. The highest enzyme activity was recorded as 316 U/ml in the optimized medium containing 8% Tannic acid, 1% Glucose, 0.4% (NH4)2HPO4, 0.1% K2HPO4, 0.1% MgSO4.7H2O, 0.01% ZnSO4.7H2O, 0.0005% NaCl in a shake-flask bioreactor at 35oC and 175 rpm. The bioreaction profile including tannic acid, gallic acid, pyrogallol, glucose concentrations, pH, biomass and extracellular tannase production were determined under the optimized conditions. The maximum extracellular tannase activity (316 U/ml) was observed on the 4th day of cultivation. However, biomass continued to increase up to the 9th day of fermentation. Increase in biomass concentration during the first two days and after the 7th day was high. The microorganism used tannic acid and glucose during the first two days by considering the sharp decrease in tannic acid and glucose concentrations. The increase in biomass concentration after the 7th day was directly proportional to the decrease in pyrogallol concentration in this period of time. The pH of the cultivation medium decreased from 5.5 to 2.3 owing to the assimilation of glucose and the production of gallic acid. Keywords: Tannase, Aspergillus niger, Enzyme production, Cultivation profile, Tannic acid.

Οι πολυφαινόλες είναι μια κατηγορία οργανικών χημικών ουσιών, που χαρακτηρίζονται από την παρουσία ενός ή περισσότερων υδροξυλίων, συνδεδεμένων με έναν ή περισσότερους αρωματικούς ή ετεροκυκλικούς δακτυλίους φαινόλης. Το ταννικό οξύ (ΤΑ), μια ειδική εμπορική μορφή της τανίνης, χρησιμοποιείται ευρέως στη βιομηχανία και αποτελεί μία από τις κυριότερες ουσίες των βιομηχανικών λυμάτων που διοχετεύονται στα υδάτινα οικοσυστήματα και στο έδαφος. Παρόλο το γεγονός ότι οι πολυφαινόλες δρουν αντιοξειδωτικά στα κύτταρα, η ισορροπία μεταξύ της αντιοξειδωτικής και της οξειδωτικής δράσης τους είναι υπό διερεύνηση. Η παρούσα μελέτη διερευνά τις αντιοξειδωτικές και οξειδωτικές επιπτώσεις του ταννικού οξέος σε αιμοκύτταρα του μυδιού Mytilus galloprovincialis, παρουσία τοξικών συγκεντρώσεων καδμίου. Συγκεκριμένα, αιμοκύτταρα που εκτέθηκαν σε διαφορετικές συγκεντρώσεις ΤΑ (1, 10, 20, 40 και 60 μΜ) για 1 h, έδειξαν σημαντική μείωση της βιωσιμότητάς τους, μόνο σε συγκεντρώσεις ΤΑ μεγαλύτερες από 40 μΜ. Παράλληλα, αιμοκύτταρα που εκτέθηκαν σε μικρομοριακές συγκεντρώσεις του μετάλλου (50 και 100 μΜ) έδειξαν σημαντική μείωση της βιωσιμότητάς τους. Προκειμένου να προσδιορίσουμε την αντιοξειδωτική ή οξειδωτική ικανότητα του ΤΑ, αιμοκύτταρα που είχαν προηγουμένως προ-επωαστεί σε διαφορετικές συγκεντρώσεις ΤΑ για 15 min, εκτέθηκαν σε μικρομοριακές συγκεντρώσεις του μετάλλου. Σύμφωνα με τα αποτελέσματά μας, κύτταρα που είχαν προ-επωαστεί σε συγκεντρώσεις ΤΑ 1- 40 μΜ, έδειξαν σημαντική αναστολή των οξειδωτικών επιπτώσεων του μετάλλου (παραγωγή σουπεροξειδικών ανιόντων/∙O2 −, οξειδίων του αζώτου/ ΝΟ, και προϊόντων λιπιδικής υπεροξείδωσης/ επίπεδα μηλονικής διαλδεϋδης), όσο και της ικανότητάς του να μειώνει τη βιωσιμότητα των κυττάρων, συγκριτικά με τις τιμές που μετρήθηκαν σε κύτταρα που εκτέθηκαν μόνο στο μέταλλο. Αντίθετα, σε κύτταρα που προ-επωάστηκαν σε ΤΑ 60 μΜ, πριν την έκθεσή τους στο μέταλλο, το ΤΑ εμφανίστηκε να δρα συνεργατικά με το μέταλλο. Τα αποτελέσματα της παρούσας μελέτης οδηγούν στο συμπέρασμα ότι το ΤΑ σε μικρομοριακές συγκεντρώσεις 1-40 μΜ μπορεί να δράσει ως ένας ισχυρός αντιοξειδωτικός παράγοντας, ενώ σε υψηλότερες συγκεντρώσεις μπορεί να προκαλέσει οξειδωτικές επιπτώσεις, ανάλογες με αυτές που προκύπτουν από ισχυρούς οξειδωτικούς παράγοντες, όπως τα κάδμιο. / Polyphenols are well-known organic substances, mainly characterized by the presence of one or more hydroxyl groups on one or more aromatic or heterocyclic phenol rings. Tannic acid (TA), a specific commercial form of tannin is a natural polyphenol, widely used in food, pharmaceutical, leather and chemical industry. It is one of the main organic compounds of industrial effluents discharged into aquatic ecosystems and soil, causing environmental pollution. Despite the fact that a lot of studies reported that polyphenols could act as antioxidants in different cells, the balance between their antioxidant and pro-oxidant properties remains still unclear. According to the later, the present study investigates the antioxidant and pro-oxidant potency of TA in haemocytes of mussel Mytilus galloprovincialis in the presence or the absence of micromolar concentrations of cadmium (Cd). Specifically, haemocytes exposed to different concentrations of TA (1, 10, 20, 40 and 60 μΜ) for 1 h, showed a significant reduction of their viability, only in concentrations higher than 40 μΜ. Furthermore, cells exposed to micromolar concentrations of Cd (50 and 100 μΜ), showed significantly increased levels of cell death, compared to those observed in control cells. In order to investigate the antioxidant or pro-oxidant ability of TA, haemocytes pre-treated for 15 min with different concentrations of TA were exposed to micromolar concentrations of the metal. According to the results, cells pre-treated with TA 1-40 μΜ, showed a significant attenuation of Cd induced effects, such as the production of superoxide (∙O2 −) and nitric oxides (NO), MDA content as well as cell death, compared to those occurred in the presence of the metal alone. On the contrary, in cells pre-treated with TA 60 μΜ before their exposure to the metal, TA seemed to act synergistically with the metal. The results of the present study could lead to the suggestion that TA in concentrations ranged within 1 and 40 μΜ could act as a major antioxidant factor, whereas in higher concentrations TA could cause oxidant effects, similar with those caused by well-known pro-oxidants, such as cadmium.

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / An alternative for the recovery of industrial fish waste is the production of films, which can be applied in food packaging. However, a major challenge is to obtain films with antimicrobial properties aiding in increased food shelf life as well as films with good mechanical properties and barriers. Therefore, in order to improve these limitations, silver nanoparticles were used due to its potential antimicrobial in food, and tannic acid (TA) as crosslinker in order to improve the mechanical and barrier properties. This study focuses in the extraction of gelatin from the Nile tilapia skin (Oreochromisniloticus) in order to produce gelatin films with embedded nanosilver (AgNPs) generated by green process and evaluate the addition of tannic acid (TA) in synthesis of AgNPs and mechanical properties of the films and barrier. A pre-treatment was conducted to obtain gelatin followed by a collagen denaturing. The characterization was done by gel strength, isoelectric point, electrophoretic analysis, fourier transform infrared (FTIR) and thermogravimetric analysis (TGA). The incorporation was performed by in situ method, the films were obtained with and without the presence of TA and AgNO3 concentrations were 0, 45, 90 and 180 mmol.L-1.The films were characterized by UV-Vis, FTIR, TGA, Mechanical properties (tensile strength and elongation at break), water vapor permeability (WVP), scanning electron microscopy (SEM) and antimicrobial analysis. It was possible to use gelatin as a reducing agent and stabilizer in the reduction of silver nanoparticles. Films produced with the addition of AT showed more suitable properties for the usage as packaging material for food, showing better WVP, water solubility and were more resistant to applied loads. In addition, they presented better antimicrobial activity. Therefore, it was possible to obtain the green AgNPs method through the incorporationof thegelatin matrix and to obtain films with excellent properties after the TA addition. / Uma alternativa de valorizaÃÃo de resÃduo de pescado produzidos por indÃstrias à a produÃÃo de filmes, que pode ser aplicados em embalagens para alimentos. PorÃm, um dos grandes desafios à obter filmes com propriedades antimicrobianas, auxiliando no aumento da vida de prateleira dos alimentos, bem como obter filmes com boas propriedades mecÃnicas e de barreiras. Para isso, a fim de melhorar essas limitaÃÃes, nanopartÃculas de prata foram utilizadas devido a sua potencial aÃÃo antimicrobiana em alimentos, e Ãcido tÃnico (AT) como agente reticulante a fim de melhorar as propriedades mecÃnicas e de barreiras. Nesse estudo objetivou-se fazer a extraÃÃo da gelatina a partir de pele de tilÃpia do Nilo (Oreochromis niloticus), visando a produÃÃo de filmes de gelatina incorporados com nanopartÃculas de prata (NPAg) geradas por processo verde e avaliar a adiÃÃo de Ãcido tÃnico (AT) na sÃntese das NPAg e nas propriedades mecÃnicas e de barreira dos filmes. Para a obtenÃÃo da gelatina foram feitos prÃ-tratamentos e em seguida a desnaturaÃÃo do colÃgeno. A caracterizaÃÃo foi feita por ForÃa de Gel, Ponto IsoelÃtrico, DistribuiÃÃo de Massa Molar, Espectroscopia no Infravermelho pro Transformada de Fourrier (FTIR) e AnÃlise TermogravimÃtrica (TGA). A incorporaÃÃo foi feita pelo mÃtodo in situ, Os filmes foram obtidos sem e com a presenÃa de AT e as concentraÃÃes de AgNO3 foram 0, 45, 90 e 180 mmol.L-1. Os filmes foram caracterizados por: UV-Vis, FTIR, TGA, Ensaios MecÃnicos, Permeabilidade ao Vapor de Ãgua (PVA), Microscopia EletrÃnica de Varredura (MEV) e AnÃlise Antimicrobiana. Foi possÃvel utilizar a gelatina como agente redutor e estabilizante na reduÃÃo de nanopartÃculas de prata. Os filmes produzidos com a adiÃÃo de AT apresentaram propriedades mais adequadas para uso como embalagem para alimentos, apresentando melhores PVA, solubilidade em Ãgua e mostraram-se mais resistentes a esforÃos aplicados. AlÃm de apresentarem melhor atividade antimicrobiana. Logo, foi possÃvel, obter pelo mÃtodo verde a incorporaÃÃo de NPAg na matriz de gelatina, alÃm, de se obter filmes com excelentes propriedades apÃs a adiÃÃo de AT.

<p>Epoxy thermosets have revolutionized the coating, adhesive, and composite industries but the chemicals from which they are synthesized have significant effects on the environment and human health not only pre-cure but also after crosslinking has occurred. Many flame retardants (FR), hardeners, and other additives used in epoxy thermosets are synthesized from petroleum-based monomers leading to significant environmental impacts at the industrial scale. Various bio-based modifiers have been developed to circumvent these environmental concerns; however, dispersing biologically-based molecules into the system without tradeoffs with other properties, especially mechanical properties and the glass transition temperature, has proven challenging. Tannic acid (TA) is a bio-based high molecular weight organic (HMWO), aromatic molecule. Although biologically sourced, TA is a pollutant in industrial wastewater streams, and there is desire to find applications in which to downcycle this molecule after extraction from these streams. The unique properties that make TA applicable in a variety of applications including leather tanning, burn wound treatment, and water purification are desirable in epoxy thermosets. In this study, we propose TA as an alternative additive for epoxy. We will uncover the usefulness of TA as an epoxy hardener and as a FR additive. Previous work uncovered that TA could be dispersed in epoxy with weights up to 37 wt%, the highest loading level achieved in literature for this molecule. Using TA as an epoxy hardener resulted in materials that had glass transition temperatures at and above 200⁰C. Using TA as a FR additive resulted in intumescent-behavior previously unseen with TA in epoxy. Chemical functionalization with acetic anhydride further enhanced the behavior resulting in a reduction of the peak heat release rate of the materials by 80%. Ongoing research in the use of solvent, metal ion complexation, and water-borne epoxy containing TA will additionally be explored. The result of this work indicated that TA showed significant promise as a biologically-based functional additive as a flame retardant and epoxy hardener and could reduce environmental impact of many currently available products.</p>