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Carvalho, Paulo Roberto Nogueira
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Id: biblio-982805
Autor: Silva, Marta Gomes da; Garcia, Adão Luiz; Carvalho, Paulo Roberto Nogueira.
Título: The annatto carotenoids and the norbixin absorption coefficient / Carotenoides de urucum e o coeficiente de absorção da norbixina
Fonte: Rev. Inst. Adolfo Lutz;(77):1-8, 2018. ilus, tab.
Idioma: en.
Resumo: Annatto seeds present cis-bixin as the major carotenoids, but the norbixin salt is the mainpigment present in dyes obtained from the alkaline extraction process. For analyzing the norbixin,the absorptions are obtained in the two spectral peaks with higher intensity, but discrepanciesin the published extinction values have led to serious doubts. Taking into account the use ofabsorption coefficient for evaluating the norbixin concentration in annatto seeds and extracts, thepresent study evaluated the absorption coefficient in various solvents and the total uncertaintyassociated with this value was determined. The norbixin standard was prepared from annattoseeds, purified by column chromatography and the purity of norbixin was evaluated by HPLC-DAD.The absorption coefficients were determined for norbixin in different solvents and the uncertaintywas evaluated. The 0.5% potassium hydroxide, the main solvent used for marketing the annattoseeds and extracts, showed the absorption coefficients of 2887 at 454nm and of 2546 at 483nm,and the estimation of expanded uncertainty (K=2) was ±86 and 85 g 100 mL-1, respectively.

O principal carotenoide em sementes de urucum é a cis-bixina, mas o sal de norbixina torna-seo principal pigmento presente em corantes obtidos pelo processo de extração alcalino.Para a análise de norbixina as absorbâncias são obtidas nos dois picos espectrais de maiorintensidade, mas discrepâncias no valor de absortividade levam a sérias dúvidas. Levando-se emconta o uso do coeficiente de absorção na avaliação da concentração de norbixina em sementesde urucum e extratos, este trabalho teve como objetivo avaliar o coeficiente de absorção emvários solventes e determinar a incerteza expandida associada a esse valor. Para a execução doestudo, um padrão de norbixina foi preparado a partir de sementes de urucum, purificado emcoluna aberta e a pureza da norbixina foi avaliada por HPLC-DAD. O coeficiente de absorçãoda norbixina foi determinado pela construção de curvas analíticas em diferentes solventes e aincerteza expandida foi avaliada. O hidróxido de potássio a 0,5%, principal solvente utilizadona comercialização de sementes de urucum e extratos, apresentou o coeficiente de absorçãodeterminado em 2887 a 454nm e 2546 a 483nm e a estimação da incerteza expandida (K=2) foi86 e 85 g 100 mL-1, respectivamente.
Descritores: Corantes
Pigmentos da Retina
Solventes
Limites: Seres Humanos
Responsável: BR91.2 - Centro de Documentação


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Id: biblio-828198
Autor: Yang, Panpan; Shi, Wenxiao; Wang, Hongkai; Liu, Hongmei.
Título: Screening of freshwater fungi for decolorizing multiple synthetic dyes
Fonte: Braz. j. microbiol;47(4):828-834, Oct.-Dec. 2016. tab, graf.
Idioma: en.
Projeto: Major Science & Technology Project of the Xinjiang Uygur Autonomous Region; . Natural Science Foundation of the Zhejiang Province.
Resumo: Abstract The biodegradation of synthetic dyes by fungi is emerging as an effective and promising approach. In the present study, freshwater fungal strains isolated from submerged woods were screened for the decolorization of 7 synthetic dyes. Subsequently, 13 isolates with high decolorization capability were assessed in a liquid system; they belonged to 9 different fungal species. Several strains exhibited a highly effective decolorization of multiple types of dyes. New absorbance peaks appeared after the treatment with 3 fungal strains, which suggests that a biotransformation process occurred through fungal biodegradation. These results showed the unexploited and valuable capability of freshwater fungi for the treatment of dye-containing effluents. The ability of certain fungi to decolorize dyes is reported here for the first time.
Descritores: Biodegradação Ambiental
Corantes/metabolismo
Água Doce/microbiologia
Fungos/isolamento & purificação
Fungos/metabolismo
-Corantes/química
Fungos/classificação
Fungos/genética
Responsável: BR1.1 - BIREME


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Monteiro, Regina Teresa Rosim
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Id: biblio-839353
Autor: Dellamatrice, Priscila Maria; Silva-Stenico, Maria Estela; Moraes, Luiz Alberto Beraldo de; Fiore, Marli Fátima; Monteiro, Regina Teresa Rosim.
Título: Degradation of textile dyes by cyanobacteria
Fonte: Braz. j. microbiol;48(1):25-31, Jan.-Mar. 2017. tab, graf.
Idioma: en.
Resumo: Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds.
Descritores: Cianobactérias/metabolismo
Corantes/metabolismo
-Sementes/efeitos dos fármacos
Têxteis
Allium/efeitos dos fármacos
Brasil
Biotransformação
Alface/efeitos dos fármacos
Aerobiose
Corantes/toxicidade
Clorófitas/efeitos dos fármacos
Espectroscopia por Absorção de Raios X
Hydra/efeitos dos fármacos
Anaerobiose
Resíduos Industriais
Mutagênicos/metabolismo
Limites: Animais
Responsável: BR1.1 - BIREME


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Id: biblio-1050804
Autor: Lima, Erinete Nogueira de; Maranhão, Kalena; Reis, Ana Cassia; Klautau, Eliza.
Título: Análise da alteração da cor de dentes artificiais após imersão em alimentos corantes / Analysis of the color change of artificial teeth after immersion in food coloring
Fonte: Rev. Salusvita (Online);37(4):839-853, 2018.
Idioma: pt.
Resumo: Introdução: apesar dos avanços tecnológicos, os materiais restauradores estão expostos ao meio bucal onde há comumente a ingestão de certos alimentos e bebidas com substâncias corantes, as quais tendem, no decorrer do tempo, causar alterações de cor nos dentes naturais, materiais restauradores e, inclusive, nos dentes artificiais utilizados para a confecção das próteses dentárias. Objetivo: avaliar in vitro o manchamento de duas marcas de dentes artificiais quando imersos em soluções corantes. Métodos: para a confecção dos 40 corpos de prova (CP), sendo 20 dentes Biotone® e 20 dentes Biolux®, utilizou-se uma broca MINICUT para desgaste dos dentes e obtenção de amostras com uma espessura padrão de 2 mm e discos de lixa d'água SOF-LEX (3M) de granulação decrescente para dar o acaba mento superficial. Os CP foram divididos em 4 grupos de estudo: G1- foram imersos no café; G2- imersos no vinho tinto; G3- imersos no urucum; e G4- na água destilada (controle). Diariamente os CP permaneceram imersos por um período de 4 horas; em seguida, foram retirados, lavados em água corrente, secos em papel absorvente, imersos em recipiente com água destilada e armazenados em estufa biológica a 37°C, nas horas subseqüentes, por 21 dias. A avaliação do manchamento foi feita nos períodos inicial (0), 7, 14 e 21 dias de imersão, através de análise computadorizada (Adobe Photoshop 7.0). Resultados e discussão: os resultados apontaram que as amostras que ficaram imersas em urucum sofreram as maiores variações, pigmentando-se desde os primeiros dias do experimento; sendo seguido pelos CP imersos em café e vinho tinto que apresentaram nível de significância semelhante quanto à alteração de cor e fator tempo. Conclusão: conclui-se que houve maior intensidade de manchamento das amostras do grupo urucum, e que a alteração de cor aumentou progressivamente em função do tempo para as duas marcas testadas.

Introduction: despite technological advances, restorative materials are exposed to the oral environment where there is a common ingestion of certain foods and beverages with coloring substances, which in the course of time tend to cause color changes in natural teeth, restorative materials and even on the artificial teeth used to make dental prostheses. Aim: to evaluate in vitro the staining of two artificial tooth marks when immersed in dye solutions. Methods: For the preparation of the 40 test specimens (CP), 20 Biotone® teeth and 20 Biolux® teeth, a MINICUT bit for tooth wear was used and samples with a standard thickness of 2 mm
Descritores: Prótese Dentária
-Clareamento Dental
Corantes
Tipo de Publ: Estudo Comparativo
Responsável: BR36.1 - Biblioteca


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Id: biblio-1015723
Autor: Wang, Jiayi; Lu, Lei; Feng, Fujuan.
Título: Combined strategies for improving production of a thermo-alkali stable laccase in Pichia pastoris
Fonte: Electron. j. biotechnol;28:7-13, July. 2017. tab, graf, ilus.
Idioma: en.
Projeto: National Natural Science Foundation of China; . Fundamental Research Funds for the Central Universities.
Resumo: Background: Laccases are copper-containing enzymes which have been used as green biocatalysts for many industrial processes. Although bacterial laccases have high stabilities which facilitate their application under harsh conditions, their activities and production yields are usually very low. In this work, we attempt to use a combinatorial strategy, including site-directed mutagenesis, codon and cultivation optimization, for improving the productivity of a thermo-alkali stable bacterial laccase in Pichia pastoris. Results: A D500G mutant of Bacillus licheniformis LS04 laccase, which was constructed by site-directed mutagenesis, demonstrated 2.1-fold higher activity when expressed in P. pastoris. The D500G variant retained similar catalytic characteristics to the wild-type laccase, and could efficiently decolorize synthetic dyes at alkaline conditions. Various cultivation factors such as medium components, pH and temperature were investigated for their effects on laccase expression. After cultivation optimization, a laccase activity of 347 ± 7 U/L was finally achieved for D500G after 3 d of induction, which was about 9.3 times higher than that of wild-type enzyme. The protein yield under the optimized conditions was about 59 mg/L for D500G. Conclusions: The productivity of the thermo-alkali stable laccase from B. licheniformis expressed in P. pastoris was significantly improved through the combination of site-directed mutagenesis and optimization of the cultivation process. The mutant enzyme retains good stability under high temperature and alkaline conditions, and is a good candidate for industrial application in dye decolorization.
Descritores: Pichia/metabolismo
Lacase/biossíntese
Lacase/genética
Bacillus licheniformis/enzimologia
-Temperatura Ambiente
Leveduras
Estabilidade Enzimática
Catálise
Mutagênese
Lacase/metabolismo
Corantes/metabolismo
Concentração de Íons de Hidrogênio
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-889238
Autor: Przystaś, Wioletta; Zabłocka-Godlewska, Ewa; Grabińska-Sota, Elżbieta.
Título: Efficiency of decolorization of different dyes using fungal biomass immobilized on different solid supports
Fonte: Braz. j. microbiol;49(2):285-295, Apr.-June 2018. tab, graf.
Idioma: en.
Projeto: Ministry of Science and Higher Education.
Resumo: Abstract Different technologies may be used for decolorization of wastewater containing dyes. Among them, biological processes are the most promising because they seem to be environmentally safe. The aim of this study was to determine the efficiency of decolorization of two dyes belonging to different classes (azo and triphenylmethane dyes) by immobilized biomass of strains of fungi (Pleurotus ostreatus - BWPH, Gleophyllum odoratum - DCa and Polyporus picipes - RWP17). Different solid supports were tested for biomass immobilization. The best growth of fungal strains was observed on the washer, brush, grid and sawdust supports. Based on the results of dye adsorption, the brush and the washer were selected for further study. These solid supports adsorbed dyes at a negligible level, while the sawdust adsorbed 82.5% of brilliant green and 19.1% of Evans blue. Immobilization of biomass improved dye removal. Almost complete decolorization of diazo dye Evans blue was reached after 24 h in samples of all strains immobilized on the washer. The process was slower when the brush was used for biomass immobilization. Comparable results were reached for brilliant green in samples with biomass of strains BWPH and RWP17. High decolorization effectiveness was reached in samples with dead fungal biomass. Intensive removal of the dyes by biomass immobilized on the washer corresponded to a significant decrease in phytotoxicity and a slight decrease in zootoxicity of the dye solutions. The best decolorization results as well as reduction in toxicity were observed for the strain P. picipes (RWP17).
Descritores: Basidiomycota/metabolismo
Poluentes Químicos da Água/metabolismo
Corantes/metabolismo
-Compostos Azo/metabolismo
Compostos de Tritil/metabolismo
Biotransformação
Células Imobilizadas/metabolismo
Adsorção
Águas Residuais
Responsável: BR1.1 - BIREME


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Id: biblio-1009153
Autor: Munjid Mustafa, Monawar; Jamal, Parveen; Fahmi Alkhatib, Ma'an; Senan Mahmod, Safa; Noraini Jimat, Dzun; Najhah Ilyas, Nurul.
Título: Panus tigrinus as a potential biomass source for Reactive Blue decolorization: isotherm and kinetic study
Fonte: Electron. j. biotechnol;26:7-11, Mar. 2017. tab, graf.
Idioma: en.
Resumo: Background: Textile and dye industries pose a serious threat to the environment. Conventional methods used for dye treatment are generally not always effective and environmentally friendly. This drove attention of scores of researchers to investigate alternative methods for the biodegradation of dyes using fungal strains. In this work, white-rot fungus (Panus tigrinus) was used as a biosorbent for the decolorization of Reactive Blue 19. The process parameters that were varied were initial concentration (50­150 mg/L), contact time (30­90 min), and pH (2­6). In addition, to gain important data for the evaluation of a sorption process, the equilibrium and kinetics of the process were determined. Results: White-rot fungus showed great potential in decolorizing Azo dyes. The strain showed the maximum decolorization of 83.18% at pH 2, a contact time of 90 min, and an initial concentration of 50 mg/L. The Langmuir isotherm described the uptake of the Reactive Blue 19 dye better than the Freundlich isotherm. Analysis of the kinetic data showed that the dye uptake process followed the pseudo second-order rate expression. Conclusion: The biosorption process provided vital information on the process parameters required to obtain the optimum level of dye removal. The isotherm study indicated the homogeneous distribution of active sites on the biomass surface, and the kinetic study suggested that chemisorption is the rate-limiting step that controlled the biosorption process. According to the obtained results, P. tigrinus biomass can be used effectively to decolorize textile dyes and tackle the pollution problems in the environment.
Descritores: Basidiomycota/química
Antraquinonas/química
Corantes/química
-Temperatura Ambiente
Compostos Azo/química
Indústria Têxtil
Fatores de Tempo
Basidiomycota/metabolismo
Biodegradação Ambiental
Cinética
Adsorção
Isoterma
Concentração de Íons de Hidrogênio
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1038609
Autor: Andrade, M. C. C; Moreno, T. M; Muccillo, M. S; Pigatto, J. A. T; Camilo, E. V.
Título: Evaluation of equine corneal endothelium after exposure to 0. 05% brilliant blue - an in vitro study / Avaliação do endotélio corneano de equinos após contato com o corante azul brilhante 0, 05% - estudo in vitro
Fonte: Arq. bras. med. vet. zootec. (Online);71(4):1158-1164, jul.-ago. 2019. graf, ilus.
Idioma: en.
Resumo: The aim of this study was to evaluate the immediate effects of 0.05% brilliant blue on corneal endothelium of horses. Thirty-eight corneas of 19 horses, male or female, of different ages were studied. Corneas were randomly divided into two groups. Group 1: Corneal endothelium was covered with 0.3mL of brilliant blue 0.05% for 60 seconds followed by rinsing with a balanced salt solution. Group 2: Corneal endothelium was covered with BSS for 60 seconds. The corneas were excised with an 8mm trephine and prepared to analyze posterior endothelial surface using a light microscope (24 corneas) and a scanning electron microscope (14 corneas). The equine posterior corneal endothelium surface observed by optical microscopy and scanning electron microscopy revealed a continuous layer of polygonal cells of uniform size and shape in both the control and treatment groups. Due to non-normal residuals at ANOVA mean comparison, a generalized linear model was utilized at 5% level of significance. The chi-square test stated that treatment and control group were not different statistically. The 0.05% brilliant blue did not cause damage to equine corneal endothelium.(AU)

Objetivou-se avaliar os efeitos imediatos de uma solução de 0,05% de azul brilhante sobre o endotélio da córnea de equinos. Trinta e oito córneas de 19 cavalos, machos ou fêmeas, de diferentes idades foram estudadas. As córneas foram divididas aleatoriamente em dois grupos. Grupo 1: O endotélio corneano foi perfundido com 0,3mL de azul brilhante 0,05% durante 60 segundos seguido por irrigação com uma solução salina balanceada. Grupo 2: O endotélio corneano foi perfundido com BSS durante 60 segundos. As córneas foram posteriormente excisadas com trépano de 8mm e preparadas para análise endotelial utilizando um microscópio óptico (24 córneas) e um microscópio eletrônico de varredura (14 córneas). A análise da superfície posterior do endotélio da córnea equina observada por microscopia óptica e microscopia eletrônica de varredura revelou uma camada contínua de células poligonais de tamanho e forma uniformes tanto no grupo controle quanto no grupo tratamento. Devido aos resíduos não normais na comparação da média de ANOVA, utilizou-se um modelo linear generalizado com nível de significância de 5%. Evidenciou-se com o teste qui-quadrado que não houve diferença estatística entre o grupo controle e o grupo tratamento. O azul brilhante de 0,05% não causou dano ao endotélio corneano de equinos.(AU)
Descritores: Kit de Reagentes para Diagnóstico/veterinária
Epitélio Posterior
Corantes/análise
Cavalos
Limites: Animais
Responsável: BR68.1 - Biblioteca Virginie Buff D'Ápice


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Id: biblio-1026335
Autor: Brammer, Sandra Patussi; Toniazzo, Claudia; Poersch, Liane Balvedi.
Título: Corantes comumente empregados na citogenética vegetal / Dyes usually employed in plant cytogenetics
Fonte: Arq. Inst. Biol;82:1-8, 2015.
Idioma: pt.
Resumo: O emprego dos corantes, na citogenética vegetal, data de muitos anos, uma vez que as pesquisas nas áreas da citologia e histologia vêm sendo desenvolvidas constantemente desde os primeiros estudos celulares no século XIX. Inicialmente, eram extraídos de fontes vegetais ou animais, sendo atualmente produzidos sinteticamente em escala comercial. Os corantes são classificados em não fluorescentes e fluorescentes, conforme suas propriedades químicas e a escolha de uso é de acordo com o tipo de estrutura celular ou grupo celular a ser analisado. A diversidade de tipos e compostos químicos existentes nos diferentes corantes proporciona sua aplicação em estudos avançados na citogenética clássica e molecular. Uma revisão de suas propriedades químicas e emprego é apresentada para os corantes não fluorescentes orceína, hematoxilina, Giemsa, carmin; e para os fluorescentes 4',6-diamidino-2-fenilindol (DAPI), cromomicina A (CMA), fluoresceína e rodamina.(AU)

The use of dyes in plant cytogenetics goes back many years, as research in the fields of cytology and histology has been constantly developed since the first cellular studies in the 19(th) century. Initially they were taken from plant or animal sources, and now they are produced synthetically on a commercial scale. These dyes are classified in fluorescent and non-fluorescent, according to their chemical properties and the choice of use is based on the type of cell structure or cell group to be analyzed. The diversity of types and chemical compounds available in different dyes provides their application in advanced and classical cytogenetics studies. A review of their chemical properties and use is presented for the non-fluorescent dyes orcein, hematoxylin, Giemsa, and carmine; and for the fluorescent dyes 4',6-diamidino-2-phenylindole (DAPI), chromomycin A (CMA), fluorescein, and rhodamine.(AU)
Descritores: Citogenética
Corantes
Corantes Fluorescentes
Hematoxilina
Responsável: BR1942.1 - NID - Biblioteca - Núcleo de Informação e Documentação


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Id: biblio-951899
Autor: Serrão, Elaine Cabral; Gama, Robson Miranda da; Dario, Michelli Ferrera; França-Stefoni, Simone Aparecida da; Bedin, Valcinir; Baby, André Rolim; Velasco, Maria Valéria Robles.
Título: Influence of different cosmetic vehicles in mechanical and physical properties of hair treated with oxidative hair dyes
Fonte: Braz. J. Pharm. Sci. (Online);54(1):e17218, 2018. tab, graf.
Idioma: en.
Resumo: ABSTRACT Hair care products play a significant role in the cosmetic market and aim at improving hair brightness, breakage resistance, and color change. In this study, we analyzed the possibility of the formulation of oxidative dyes in different vehicles impacting the hair's both mechanical and physical properties. Light brown and light blond dyes were prepared using eight different vehicles. Among these, four vehicles were emulsifying agents and four gelling agents. Each formulation was applied to two types of virgin Caucasian hair (light blond and dark brown). Physical, chemical, and organoleptic properties of each formulation were assessed, as well as changes in hair parameters after oxidative dyeing, such as staining intensity, brightness, and breaking strength. The parameters of color and brightness differed in some formulations, but the hair type also responded differently. Brightness parameter was increased in dark brown hair colored with both dyes, whereas light blond hair showed the opposite result. Regarding the breaking strength, there were no significant differences between the two kinds of tresses. Cosmetic formulations should adjust the consumer desired effects (e.g. color change) in order to present minimal drawbacks (e.g. decrease of hair brightness and strength). Thus, the study of different vehicles is important when establishing the best oxidative dye formulation.
Descritores: Tinturas para Cabelo/análise
Preparações para Cabelo/análise
-Cor de Cabelo
Corantes/efeitos adversos
Melaninas/classificação
Responsável: BR40.1 - DBD - Divisão de Biblioteca e Documentacão do Conjunto das Químicas



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