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1.
Mycologia ; 112(5): 859-870, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821020

RESUMO

Paper-based works of art and documents of cultural importance kept in museums and libraries can show notorious signs of deterioration, including foxing stains, caused by fungal colonization. Some of the main chromophore agents of fungal origin that deteriorate paper and therefore affect paper cultural heritage both aesthetically and structurally are the group of pigments called melanins. Thus, knowledge of the diversity and features of fungal melanins and of the melanization pathways of fungi growing on paper is key to removing these pigments from paper-based works of cultural importance. This review provides an approach about the current knowledge of melanins synthesized by paper-colonizing fungi, their localization in the fungal structures, and their role in the deterioration of paper. This knowledge might contribute to developing new, effective, and sustainable strategies of restoration and conservation of historical documents and works of art based on paper.


Assuntos
Arte , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Acervo de Biblioteca , Melaninas/efeitos adversos , Melaninas/metabolismo , Papel , Museus , Pigmentos Biológicos/efeitos adversos , Pigmentos Biológicos/metabolismo
2.
Contact Dermatitis ; 82(2): 73-82, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31626330

RESUMO

BACKGROUND: Red tattoos are prone to allergic reactions. The identity of the allergen(s) is mostly unknown. OBJECTIVES: Chemical analysis of human skin biopsies from chronic allergic reactions in red tattoos to identify culprit pigment(s) and metals. MATERIAL AND METHODS: One hundred four dermatome biopsies were analyzed by matrix-assisted laser desorption/ionization tandem mass spectrometry (MALDI-MS/MS) for identification of commonly used organic pigments. Metal concentrations were assessed by inductively coupled plasma (ICP)-MS and x-ray fluorescence (XRF). Fourteen patients had cross-reactions in other red tattoos. RESULTS: In total, the identified pigments were mainly azo Pigment Red (P.R.) 22 (35%), P.R. 210 (24%), P.R. 170 (12%), P.R. 5 (0.9%), P.R. 112 (0.9%), and Pigment Orange (P.O.) 13 (11%). P.R. 122 (0.9%) and Pigment Violet (P.V.) 23 (8%) were also common. P.R. 22, P.R. 170, and P.R. 210 also dominated in patients with cross-reactions. In 22% of the biopsies, no red pigment was detected. Element analysis indicated the presence of the sensitizers nickel and chromium. CONCLUSIONS: P.R. 22, P.R. 170, and P.R. 210 were identified as the prevailing pigments behind chronic allergic reactions in red tattoos. The epitope causing the reaction might be a pigment-degradation product. Metal contamination may derive from different sources, and its role in red tattoo allergy cannot be ascertained.


Assuntos
Corantes/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Pigmentos Biológicos/efeitos adversos , Tatuagem/efeitos adversos , Adulto , Alérgenos/efeitos adversos , Feminino , Humanos , Tinta , Masculino , Espectrometria de Massas em Tandem
4.
Biotechnol Prog ; 35(1): e2684, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30006968

RESUMO

The population interest in health products is increasing day-by-day. Thus, the demand for natural products to be added in food and pharmaceutical commodity is also rising. Among these additives, colorants, which provides color to products, can be produced by microorganism through bioprocess. Looking for new source of natural colorants, fungi have been employed to this purpose producing novel and safer natural colorants. So, the main goal of this study was to describe a Talaromyces species able to produce natural colorants and investigate nutritional parameters of colorants production using statistical tool. The taxonomy classified the microorganism as Talaromyces amestolkiae. The statistical design evaluated pH and glucose, meat extract and meat peptone concentration as independent variables, and red colorants production as main response. Under the best condition (g/L: glucose 30, meat extract 1, meat peptone 10, and initial pH of 7.0) an increase of 229% in the red colorant production was achieved as compared with the initial media used. The dried fermented broth containing red colorants showed low cytotoxicity against fibroblasts cells (IC50 > 187.5 g/L) and effective antimicrobial activity against S. aureus (MIC of 2.5 g/L). Thus, T. amestolkiae colorants can be attractive to food and pharmaceutical applications as it does not produce toxic compounds and can promote protection against microorganism contaminants. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2684, 2019.


Assuntos
Pigmentos Biológicos/efeitos adversos , Pigmentos Biológicos/farmacologia , Talaromyces/classificação , Talaromyces/metabolismo , Fermentação , Fibroblastos/efeitos dos fármacos , Filogenia , Pigmentos Biológicos/metabolismo , Staphylococcus aureus/efeitos dos fármacos
5.
São Paulo; s.n; s.n; 2019. 183 p. graf, tab, ilus.
Tese em Português | LILACS | ID: biblio-1007409

RESUMO

Extradiol dioxigenases são enzimas que catalisam a clivagem oxidativa de ligações C-C entre grupos hidroxila fenólicos adjacentes utilizando catecóis como substratos. Esta classe de enzimas é bem caracterizada em bactérias, onde catalisam a degradação de compostos aromáticos. Na maioria das plantas Caryophyllales, como a beterraba, primavera e a maravilha, L-3,4-diidroxifenilalanina (L-DOPA) extradiol dioxigenases (DODAs) catalisam a clivagem oxidativa de L-DOPA na posição 4,5 gerando o ácido betalâmico, aldeído precursor das betalaínas, uma classe de pigmentos naturais que substitui as antocianinas na pigmentação dessas espécies. Alguns fungos basidiomicetos também produzem betalaínas, como o agário-das-moscas (Amanita muscaria). Nesse organismo, DODA é capaz de catalisar uma clivagem adicional na posição 2,3 da L-DOPA, formando muscaflavina, um isômero do ácido betalâmico que dá origem a uma outra classe de pigmentos naturais: as higroaurinas. Desde a caracterização do gene dodA, o qual codifica para a DODA de A. muscaria (AMAMU), não existem relatos na literatura que explorem a promiscuidade catalítica desta enzima, sua relação com outras linhagens de DODAs e a síntese quimioenzimática de betalaínas a partir desta enzima. Dessa forma, buscamos contextualizar as relações filogenéticas e funcionais entre AMAMU e diferentes linhagens de DODAs, bem como estabelecer um método que viabilize a clonagem, expressão heteróloga e caracterização funcional destaenzima. As análises filogenéticas revelaram que AMAMU possui uma evolução convergente com DODAs de plantas e bactérias e que, apesar de AMAMU ser funcionalmente homóloga à DODA da bactéria Escherichia coli, esta última apresenta homologia com DODAs de plantas. Logo, não há uma relação direta entre a sequência primária de DODAs e sua função. Nós também demonstramos que não há uma relação entre a expressão de transcritos de BvDODA1, e de seu parálogo BvDODA2, e a diferença de pigmentação entre variedades de beterrabas amarelas e vermelhas. A clonagem da sequência codificadora (CDS) publicada para o gene dodA de A. muscaria resultou na retenção do primeiro íntron, o que impedia a sua expressão. Então, uma nova CDS de 558 nucleotídeos foi proposta para este gene, a qual inclui um códon de início da tradução que se mantém na fase de leitura e codifica para uma proteína de 185 resíduos, 43 a menos que AMAMU. A expressão desta CDS resultou na proteína recombinante AmDODA, capaz de catalisar a síntese de ácido betalâmico e muscaflavina a partir de L-DOPA e D-DOPA. AmDODA possui um tamanho aproximado de 22 kDa, com um pH ótimo de atividade de 8,5 e uma constante de Michaelis (KM) de 3,7 ± 0,9 mmol L-1 e de velocidade máxima (Vmax) de 3,3 ± 0,4 µ mol min-1 mg-1. Sua utilização foi demonstrada na síntese quimioenzimática de betalaínas-modelo com potencial aplicação como sondas para microscopia confocal de fluorescência de dois fótons. Neste contexto, esta Tese explora os aspectos moleculares, bioquímicos e biológicos da DODA do fungo A. muscaria e traz importantes contribuições acerca da pigmentação por betalaínas na natureza


Extradiol dioxigenases are enzymes that catalyze the oxidative cleavage of C-C bonds between adjacent phenolic hydroxyl groups using catechols as substrates. This class of enzymes is well characterized in bacteria, where they catalyze the degradation of aromatic compounds. In most plants of the Order Caryophyllales, such as beet, paperflower and four o'clock flower, L-3,4-dihydroxyphenylalanine (L-DOPA) extradiol dioxygenases (DODAs) catalyze the oxidative 4,5-cleavage of L-DOPA generating the betalamic acid, an aldehyde precursor of the betalains, a class of natural pigments that replaces anthocyanins in the pigmentation of these species. Some basidiomycete fungi also produce betalains, such as the fly agaric (Amanita muscaria). In this organism, DODA is able to catalyze an additional 2,3-cleavage of L-DOPA, yielding muscaflavine, an isomer of betalamic acid that gives rise to another class of natural pigments: the hygroaurins. Since the characterization of the dodA gene, which encodes the A. muscaria DODA (AMAMU), there are no reports in the literature that explore the catalytic promiscuity of this enzyme, its relation to other DODAs and the chemoenzymatic synthesis of betalains from this enzyme. Thus, we seek to contextualize the phylogenetic and functional relationships between AMAMU and different DODA lineages, as well as to establish a method that enable the cloning, heterologous expression and functional characterization of this enzyme. Phylogenetic analysis revealed that AMAMU has a convergent evolutionwith plant and bacterial DODAs and that although AMAMU is functionally homologous to the DODA of the Escherichia coli bacteria, this latter is homologous to the plant DODAs. Therefore, there is no direct relationship between the primary sequence of DODAs and their function. We have also shown that there is no relationship between the expression of BvDODA1 transcripts, and its BvDODA2 paralogue, and the pigment difference between yellow and red beet varieties. Cloning of the published coding sequence (CDS) for the dodA gene of A. muscaria resulted in the retention of the first intron, which prevented its expression. Then, a new CDS of 558 nucleotides was proposed for this gene, which includes a translation start codon that remains in the open reading frame and encodes for a protein 185 residues long, 43 less than AMAMU. Expression of this CDS resulted in the recombinant AmDODA protein, able to catalyze the synthesis of betalamic acid and muscaflavine from L-DOPA and D-DOPA. AmDODA has an approximate size of 22 kDa, with an optimum activity pH of 8.5 and a Michaelis constant (KM) of 3.7 ± 0.9 mmol L-1 and a maximum velocity (Vmax) of 3.3 ± 0.4 µmol min-1 mg-1. Its use was demonstrated in the chemoenzymatic synthesis of betalains-model with potential application as probes for confocal microscopy of two-photon fluorescence. In this context, this thesis explores the molecular, biochemical and biological aspects of the DODA of the fungus A. muscaria and brings important contributions about the pigmentation by betalains in nature


Assuntos
Filogenia , Pigmentos Biológicos/efeitos adversos , Agaricus muscarius/análise , Dioxigenases/química , Pigmentação , Betalaínas
7.
J Sci Food Agric ; 96(5): 1420-30, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-26415572

RESUMO

Phytogenic pigments are secondary plant compounds responsible for coloring effects in plant tissues. In particular, phenolic flavonoids and terpenoid carotenoids, but also rare compounds like curcumin and betalain, form this group of biochemical agents used in animal nutrition. From the perspective of ecological mutuality between plants and animals, these compounds are of crucial importance because they serve as visual attraction for herbivores but also signal nutritional and/or health-promoting values. This review focuses on the properties of phytogenic pigments which are likely to impact feed intake and preferences of livestock. Also natural prophylactic and/or therapeutic properties and, in particular, the potential of pigments to enhance quality and health value of animal products for human consumption are important issues. Nevertheless, reasonable limits of use due to possible adverse indications have been suggested recently. Pathways of digestion, metabolism and excretion in animals play a crucial role not only in the evaluation of effectiveness but also in the prediction of potential risks for human consumption. The popularity of natural feed additives is growing; therefore, more research work is needed to better understand metabolic pathways in the animal's body and to better estimate the potentials and risks of pigmenting plant compounds used in animal nutrition.


Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Pigmentos Biológicos/efeitos adversos , Pigmentos Biológicos/análise , Plantas/química , Animais , Antioxidantes , Betalaínas , Carotenoides , Curcumina , Ecologia , Flavonoides , Aditivos Alimentares , Promoção da Saúde , Humanos , Valor Nutritivo , Fatores de Risco
8.
Food Chem Toxicol ; 59: 527-33, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23831194

RESUMO

An ethanol-soluble pigment extract was separated from fermented Zijuan Pu-erh tea. The compositions of the ethanol soluble pigment extract were analyzed by high-performance liquid chromatography-tandem mass spectroscopy (HPLC-MS/MS). The extract was prepared into a series of ethanol solutions and analyzed for free radical-scavenging activities (against two free radicals: 1,1-diphenyl-2-picrylhydrazyl (DPPH) and (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO)) and in vitro anti-oxidative properties. Electron spin resonance spectroscopy showed that the peaks of DPPH and TEMPO decreased with increasing extract concentration, suggesting that the extract had excellent free radical-scavenging activities. In vitro cell culture suggested that, at 50-200 mg/L, the extract had no measurable effect on the viability of vascular endothelial cells (ECV340) but produced significant protective effects for cells that underwent oxidative injuries due to hydrogen peroxide (H2O2) treatment. Compared with the H2O2 treatment alone cells group, 200 mg/L of the extract increased the activity of superoxide dismutase (SOD) in cells by 397.3%, and decreased the concentration of malondialdehyde (MDA) and the activity of lactate acid dehydrogenase (LDH) by 47.8% and 69.6%, respectively. These results suggest that the extract has excellent free radical scavenging and anti-oxidative properties.


Assuntos
Antioxidantes/farmacologia , Endotélio Vascular/efeitos dos fármacos , Lactato Desidrogenases/metabolismo , Pigmentos Biológicos/farmacologia , Extratos Vegetais/farmacologia , Superóxido Dismutase/metabolismo , Chá/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Camellia sinensis/química , Camellia sinensis/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , China , Dieta/etnologia , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Endotélio Vascular/metabolismo , Etanol/química , Etnofarmacologia , Fermentação , Manipulação de Alimentos , Sequestradores de Radicais Livres/efeitos adversos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Humanos , Lactato Desidrogenases/química , Malondialdeído/antagonistas & inibidores , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pigmentos Biológicos/efeitos adversos , Pigmentos Biológicos/química , Pigmentos Biológicos/isolamento & purificação , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Solubilidade , Solventes/química , Superóxido Dismutase/química , Chá/microbiologia
9.
Annu Rev Food Sci Technol ; 3: 59-77, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22385164

RESUMO

Replacement of artificial food dyes with natural colorants is a current marketing trend, notwithstanding the fact that neither the United States nor the European Union (EU) has defined natural with respect to food colors. Consumer groups have concerns over the safety of synthetic colorants, and in addition, many of the naturally derived colorants provide health benefits. Food scientists frequently have the assignment of replacing artificial colorants with natural alternatives. This can be challenging, as naturally derived colorants are usually less stable, and all desired hues might, in fact, not be obtainable. In this review, the chemical and physical properties, limitations, and more suitable applications for those colorants that are legally available as substitutes for the synthetic colorants are summarized. Issues and challenges for certain foods are discussed, and in addition, colorants that may be available in the future are briefly described.


Assuntos
Aditivos Alimentares/química , Tecnologia de Alimentos , Pigmentos Biológicos/química , Corantes/efeitos adversos , Corantes/química , Aditivos Alimentares/efeitos adversos , Inocuidade dos Alimentos , Tecnologia de Alimentos/tendências , Pigmentos Biológicos/efeitos adversos
10.
Arch Oral Biol ; 56(3): 285-93, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21112045

RESUMO

OBJECTIVE: The aim of the present study was to assess the null hypothesis that there are no differences of affinity between pigments and human whole saliva (WS), and the affinity is not influenced by the functional groups of pigments, temperatures, pH values, and salt concentrations. METHODS: The affinity constants of interactions between WS and theaflavin (TF)/curcumin (Cur)/cyanidin (Cy) were determined by surface plasmon resonance (SPR) and fluorescence quenching. Mass-uptake at various temperatures, pH values, and salt concentrations was also carried out. RESULTS: The order of affinity of the pigments binding to WS is TF>Cur>Cy. A large number of complexes and precipitations of pigments/proteins were formed through a quick, strong, and almost irreversible binding process. The mass-uptake of pigments was affected not only by the functional groups, but also by molecular weight of pigments, temperatures, pH values, and salt concentrations. CONCLUSION: The complex of pigments may easily and rapidly deposit onto the WS film, and are difficult to remove from the WS surface. However, the complex of pigments can be reduced by properly regulating the physicochemical conditions, such as temperatures, pH values, and salt concentrations.


Assuntos
Película Dentária/metabolismo , Pigmentos Biológicos/metabolismo , Saliva/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Descoloração de Dente/induzido quimicamente , Adsorção , Adulto , Análise de Variância , Antocianinas/metabolismo , Biflavonoides/metabolismo , Ligação Competitiva , Catequina/metabolismo , Curcumina/metabolismo , Feminino , Humanos , Concentração de Íons de Hidrogênio , Proteínas Imobilizadas/química , Masculino , Pessoa de Meia-Idade , Peso Molecular , Pigmentos Biológicos/efeitos adversos , Ligação Proteica , Espectrometria de Fluorescência , Estatísticas não Paramétricas , Ressonância de Plasmônio de Superfície , Temperatura , Descoloração de Dente/metabolismo , Adulto Jovem
11.
J Ethnopharmacol ; 124(3): 635-8, 2009 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-19570628

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hydroxysafflor yellow A (HSYA) was isolated from the dried flower of Carthamus tinctorius L. which was extensively used in traditional Chinese medicine to treat diseases due to blood stasis. However, there have been few detailed pharmacokinetic studies about HSYA on human beings. AIM OF THE STUDY: The aim was to investigate the pharmacokinetic characteristics of HSYA in healthy Chinese female volunteers. MATERIALS AND METHODS: The volunteers were given intravenous infusion of single doses of safflor yellow injection (containing HSYA 35, 70 and 140 mg) in separate trial periods with 1 week washout period. The concentration levels of HSYA in plasma were determined with HPLC. Various pharmacokinetic parameters were estimated from the plasma concentration versus time data using non-compartmental methods. RESULTS: The C(max) values were 2.02+/-0.18, 7.47+/-0.67 and 14.48+/-4.71 microg/mL after the administration of single doses of 35, 70, and 140 mg of HSYA, respectively. The corresponding values of AUC(0-15 h) were 6.57+/-1.20, 25.90+/-4.62 and 48.47+/-12.11 microg/(mL h(-1)), and the values of t(1/2) were 3.21+/-1.26, 3.33+/-0.68 and 2.98+/-0.09 h. The Student-Newman-Keuls test results showed that C(max) and AUC(0-15 h) were both linearly related to dose. CONCLUSIONS: In this study, the pharmacokinetic properties of HSYA are based on first-order kinetics over the dose range tested.


Assuntos
Chalcona/análogos & derivados , Pigmentos Biológicos/farmacocinética , Quinonas/farmacocinética , Adulto , Área Sob a Curva , Sequência de Carboidratos , Chalcona/administração & dosagem , Chalcona/efeitos adversos , Chalcona/farmacocinética , Estudos Cross-Over , Feminino , Humanos , Infusões Intravenosas , Dados de Sequência Molecular , Pigmentos Biológicos/administração & dosagem , Pigmentos Biológicos/efeitos adversos , Controle de Qualidade , Quinonas/administração & dosagem , Quinonas/efeitos adversos , Padrões de Referência , Riboflavina/química
12.
J Cosmet Sci ; 59(5): 431-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18841307

RESUMO

In this study, a stable red pigment was prepared from Lithospermum erythrorhizon via supercritical carbon dioxide extraction. The optimal extraction conditions were 400 bar and 60 degrees C. The patch tests indicated that up to 10% of the red pigment was acceptable from a skin irritation standpoint. According to the results of the CIE LAB chromaticity test, the color difference was acceptable when compared to commercial synthetic red pigments. The light-illuminated color stability test indicated that the pigment was more stable than the red pigment extracted with ethanol. The higher stability was also demonstrated in the DPPH antioxidant activity test. The supercritical red pigment harbored elevated amounts of shikonin and derivatives, and appears to be usable as a stable red pigment for cosmetic color products.


Assuntos
Cosméticos/isolamento & purificação , Lithospermum/química , Pigmentos Biológicos/isolamento & purificação , Adulto , Compostos de Bifenilo/química , Dióxido de Carbono/química , Cromatografia com Fluido Supercrítico/instrumentação , Cromatografia com Fluido Supercrítico/métodos , Cosméticos/efeitos adversos , Cosméticos/farmacologia , Estabilidade de Medicamentos , Feminino , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Humanos , Hidrazinas/química , Masculino , Naftoquinonas/efeitos adversos , Naftoquinonas/isolamento & purificação , Naftoquinonas/farmacologia , Picratos , Pigmentos Biológicos/efeitos adversos , Pigmentos Biológicos/farmacologia , Extratos Vegetais/química , Raízes de Plantas/química , Testes Cutâneos
13.
Tidsskr Nor Laegeforen ; 124(7): 933-5, 2004 Apr 01.
Artigo em Norueguês | MEDLINE | ID: mdl-15060640

RESUMO

BACKGROUND: Obtaining a tattoo has become increasingly popular in recent years. However, the degree to which tattooing represents a health risk in the form of infections is still a matter of debate. The aim of the present study was to investigate the microbial content of tattooing dyes and pigments (colourants). MATERIAL AND METHODS: Microbes present in colourants used for tattooing were counted and identified using standard techniques and rapid identification systems. RESULTS: Seven of in total twelve colourants contributed by five studios contained bacteria. No fungi were found. Three solutions contained more than 10 8 bacteria/ml, chiefly aerobic, Gram-negative rods including Pseudomonas aeruginosa. No primary pathogens were found, however, the high colony counts found for some samples may represent infectious doses of a wide range of bacteria. INTERPRETATION: Although required by current regulations to be sterile, a number of colourants were highly contaminated with bacteria. The detection of bacteria in colourants necessitates a review of the studios' internal control procedures. In addition, the appropriate monitoring body should initiate testing of colourants in order to ascertain if these are contaminated at the time of purchase, or become so during use.


Assuntos
Bactérias/isolamento & purificação , Corantes/efeitos adversos , Pigmentos Biológicos/efeitos adversos , Tatuagem/efeitos adversos , Infecções Bacterianas/transmissão , Contaminação de Equipamentos , Humanos , Higiene , Noruega
17.
Crit Rev Food Sci Nutr ; 42(1): 53-66, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11837241

RESUMO

The dyestuff industry is suffering from the increases in costs of feedstock and energy for dye synthesis, and they are under increasing pressure to minimize the damage to the environment. The industries are continuously looking for cheaper, more environmentally friendly routes to existing dyes. The aim of this minireview is to discuss the most important advances in the fungal pigment area and its interest in biotechnological applications. Characteristic pigments are produced by a wide variety of fungi and the chemical composition of natural dyes are described. These pigments exhibit several biological activities besides cytotoxicity. The synthetic pigments authorized by the EC and in USA and the natural pigments available in the world market are discussed. The obstacle to the exploitation of new natural pigments sources is the food legislation, requesting costly toxicological research, manufacturing costs, and acceptance by consumers. The dislike for novel ingredients is likely to be the biggest impediment for expansion of the pigment list in the near future. If the necessary toxicological testing and the comparison with accepted pigments are made, the fungal pigments, could be acceptable by the current consumer. The potentiality of pigment production in Brazil is possible due to tremendous Amazonian region biodiversity.


Assuntos
Meio Ambiente , Fungos/química , Fungos/metabolismo , Pigmentos Biológicos/efeitos adversos , Pigmentos Biológicos/química , Pigmentos Biológicos/biossíntese
19.
Contact Dermatitis ; 42(6): 318-25, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10871094

RESUMO

13 balsam of Peru (Myroxylon Pereirae) patch-test-positive subjects are re-tested with 25% balsam of Peru in petrolatum and with serial doses printed on polyester squares. All substances are applied with tape strips for 3, 6, 24 (1 day [D]), 48 (2D), 72 (3D) and 96 h (4D) on each subject and for 96 h (4D) with plastic foils. Tests are followed visually and with perfusion assessments from 3 h to 9 days. Results show that pigment remnants following detachment of patches affect perfusion assessments. Such effect due to pigment is supported by readings of patch tests through the petrolatum test substance while applied with transparent foils. For most reactions, good agreement is observed between the assessment techniques when peak assessment values of reactions are compared. There is inter-individual variation in perfusion with identical tests. With the petrolatum test substance, increased visible reactivity was observed when the application time was extended up to 24 h (1D), while extension of application time increased perfusion in most cases except for an extension from 24 (2D) to 48 h (4D) where decreased perfusion resulted in most cases. Dose and application time did not affect the timing of highest reactivity of reactions in most cases.


Assuntos
Bálsamos/efeitos adversos , Dermatite Alérgica de Contato/fisiopatologia , Eritema/fisiopatologia , Testes do Emplastro/métodos , Pigmentos Biológicos/efeitos adversos , Pele/irrigação sanguínea , Adulto , Bálsamos/química , Circulação Sanguínea/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/etiologia , Eritema/induzido quimicamente , Eritema/diagnóstico , Feminino , Humanos , Fluxometria por Laser-Doppler , Masculino , Microdiálise/instrumentação , Pessoa de Meia-Idade , Perfusão , Pigmentos Biológicos/isolamento & purificação , Reprodutibilidade dos Testes , Pele/efeitos dos fármacos
20.
Contact Dermatitis ; 42(6): 326-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10871095

RESUMO

To find an ideal test technique for as low a dose of balsam of Peru (Myroxylon Pereirae) as possible, subjects testing positive to balsam of Peru are re-tested with a 25% concentration of balsam of Peru in petrolatum. Applications are with Finn Chambers for 6 different application times, and directly by foils for 96 h (4 days (D)). The goals are to confirm which subjects are positive and which are not, and, using that information, to see if it is possible to distinguish between these 2 groups, tested concomitantly at much lower serial dose levels, in terms of perfusion or by visual assessments. 5 different serial doses are applied with strips for 3-96 h (4D) and with foils for 96 h (4D). The Finn Chamber tests allow a distinction between visually positive and negative subjects supported by perfusion assessments. With the foils, a 24x lower serial dose level than with the 25% test substance is sufficient to distinguish between positive and negative subjects in terms of perfusion values. This approach requires readings up to 9 days. With this test, the visual approach yields only 3 of 10 positive subjects. This study demonstrates that a lower test dose is possible with perfusion assessments compared to visual ones.


Assuntos
Alérgenos/efeitos adversos , Bálsamos/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Eritema/induzido quimicamente , Testes do Emplastro/métodos , Pigmentos Biológicos/efeitos adversos , Pele/efeitos dos fármacos , Adulto , Alérgenos/administração & dosagem , Bálsamos/administração & dosagem , Dermatite Alérgica de Contato/fisiopatologia , Eritema/fisiopatologia , Reações Falso-Positivas , Feminino , Humanos , Fluxometria por Laser-Doppler , Masculino , Microdiálise/instrumentação , Pessoa de Meia-Idade , Perfusão , Pigmentos Biológicos/administração & dosagem , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Pele/irrigação sanguínea
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