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1.
Sci Total Environ ; 654: 1379-1388, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30527887

RESUMO

Machu Picchu Inca sanctuary (Cusco Region, Peru) was constructed on a granitic plateau, better known as Vilcabamba batholith. One of the most important carved granitic rocks from this archaeological site is the Sacred Rock, used by Inca citizens for religious rituals. Due to the location and climatic conditions, different rocks from this archaeological site are affected by biocolonizations. Concretely, the Sacred Rock shows flaking and delamination problems. In this work, a non-destructive multi analytical methodology has been applied to determine the possible role of the biodeteriogens, forming the biological patina on the Sacred Rock, in the previously mentioned conservation problems. Before characterizing the biological patina, a mineralogical characterization of the granitic substrate was conducted using X-ray Diffraction, Raman microscopy (RM) and micro energy dispersive X-ray fluorescence spectrometry. For the identification of the main biodeteriogens in the biofilm, Phase Contrast Microscopy was used. RM also allowed to determine the distribution (imaging) and the penetration (depth profiling) of the biogenic pigments present in the biopatina. Thanks to this study, it was possible to asses that some colonizers are growing on inner areas of the rock, reinforcing their possible assistance in the delamination. Moreover, the in-depth distribution of a wide variety of carotenoids in the patinas allowed to approach the penetration ability of the main biodeteriogens and the diffusion of these biogenic pigments to the inner areas of the rocky substrate.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cianobactérias/fisiologia , Líquens/fisiologia , Microalgas/fisiologia , Arqueologia , Cianobactérias/isolamento & purificação , Líquens/isolamento & purificação , Microalgas/isolamento & purificação , Microscopia Óptica não Linear , Peru , Pigmentos Biológicos/classificação , Dióxido de Silício , Espectrometria por Raios X , Análise Espectral Raman , Difração de Raios X
2.
Annu Rev Food Sci Technol ; 8: 261-280, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-28125346

RESUMO

The color of food is often associated with the flavor, safety, and nutritional value of the product. Synthetic food colorants have been used because of their high stability and low cost. However, consumer perception and demand have driven the replacement of synthetic colorants with naturally derived alternatives. Natural pigment applications can be limited by lower stability, weaker tinctorial strength, interactions with food ingredients, and inability to match desired hues. Therefore, no single naturally derived colorant can serve as a universal alternative for a specified synthetic colorant in all applications. This review summarizes major environmental and biological sources for natural colorants as well as nature-identical counterparts. Chemical characteristics of prevalent pigments, including anthocyanins, carotenoids, betalains, and chlorophylls, are described. The possible applications and hues (warm, cool, and achromatic) of currently used natural pigments, such as anthocyanins as red and blue colorants, and possible future alternatives, such as purple violacein and red pyranoanthocyanins, are also discussed.


Assuntos
Corantes de Alimentos/isolamento & purificação , Pigmentos Biológicos/isolamento & purificação , Cor , Corantes de Alimentos/química , Corantes de Alimentos/classificação , Indústria Alimentícia/legislação & jurisprudência , Humanos , Estrutura Molecular , Pigmentos Biológicos/química , Pigmentos Biológicos/classificação
3.
Neotrop. ichthyol ; 13(3): 461-470, July-Sept. 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-760455

RESUMO

The rio Madeira is the largest white-water tributary of the Amazon, and is currently the river drainage with the highest fish species diversity in the world. A new species of Panaqolus was recognized from the middle Madeira and Mamoré rivers (Brazil) and from the Madre de Dios drainage (Peru) and it is described herein. This new species is readily distinguished from its congeners by the large number of white dots distributed all over the body and by its remarkable amplitude of color pattern variation, ranging from a pale, light brown, to dark brown and almost black background coloration. The new species closely resembles P. albomaculatus but has more and smaller dots on the body, a smaller orbital diameter (12.5-16.8% head length vs. 16.0-20.0%) and longer maxillary barbels (9.7-19.6% head length vs. 1.6-8.9%). The new species is the second of the genus Panaqolus described for a Brazilian location after nearly 80 years of the description of P. purusiensis.


O rio Madeira é o maior afluente de água branca do rio Amazonas e é atualmente o rio com o maior número de espécies do mundo. Uma nova espécie de Panaqolusfoi reconhecida do médio rio Madeira, do rio Mamoré (ambos no Brasil) e da bacia do Río Madre de Dios (Peru) e é descrita aqui. Esta nova espécie se distingue de suas congêneres pela grande quantidade de pontos brancos espalhados pelo corpo e grande variabilidade na sua coloração, variando de um fundo branco a marrom claro até marrom escuro e quase preto. A espécie se assemelha a P. albomaculatus da qual se distingue por ter mais manchas de menor tamanho no corpo, olhos menores (12,5-16,8% do comprimento da cabeça vs. 16,0-20,0%) e barbilhões maxilares mais compridos (9,7-19,6% comprimento da cabeça vs. 1,6-8,9%). A nova espécie é a segunda de Panaqolus descrita para uma localidade no Brasil, aproximadamente 80 anos após a descrição de P. purusiensis.


Assuntos
Animais , Peixes-Gato/anatomia & histologia , Peixes-Gato/classificação , Peixes-Gato/genética , Pigmentos Biológicos/análise , Pigmentos Biológicos/classificação
4.
Prikl Biokhim Mikrobiol ; 50(2): 125-34, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25272728

RESUMO

This review is dedicated to the research on the functions of melanin pigments in fungi. The participation of melanin pigments in protection from environmental factors is considered. Data on the biosynthetic pathways and types of melanin pigments in fungi are presented.


Assuntos
Parede Celular/metabolismo , Fungos/metabolismo , Melaninas/biossíntese , Pigmentos Biológicos/biossíntese , Adaptação Biológica , Parede Celular/química , Parede Celular/ultraestrutura , Fungos/química , Fungos/ultraestrutura , Melaninas/química , Melaninas/classificação , Pigmentos Biológicos/química , Pigmentos Biológicos/classificação , Temperatura Ambiente , Raios Ultravioleta
5.
PLoS One ; 8(5): e64082, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23675520

RESUMO

Theory suggests that aposematism, specifically the learned avoidance of unprofitable prey via memorable color patterns, should result in selection for pattern uniformity. However, many examples to the contrary are seen in nature. Conversely, honest sexual signals are likely to exhibit greater variation because they reflect underlying variation in mate quality. Here we aim to characterize and quantify the mechanistic causes of color in Tectocoris diophthalmus [corrected] to shed light on the costs of color production, and thus the potential information content of its color signals. We use Tectocoris diophthalmus [corrected] because it is a weakly-defended stinkbug, and presents elements that have classically been studied in the context of aposematism (red coloring), and sexual selection (sexual dichromatism and iridescent coloring). Pigment analysis reveals that variation in orange coloration is due to the amount of erythropterin pigment, stored in intracellular granules. This pigment is common in Heteroptera, and as an endogenously produced excretory byproduct is unlikely to reflect mate quality or variation in unprofitability of the bug. Electron microscopy reveals the iridescent patches are caused by an epicuticular multilayer reflector, and the hue and patch size are directly related to the layer widths and extent of coverage of this layering. Furthermore, we identified melanin as an essential component of the multilayer reflector system; therefore, the quality of the iridescent patches may be affected by aspects of rearing environment and immunocompetence. We posit that T. diophthalmus [corrected] has co-opted the melanic patches of a 'typical' red and black aposematic signal, transforming it into a complex and variable iridescent signal that may enhance its capacity to display individual quality.


Assuntos
Heterópteros/metabolismo , Pigmentos Biológicos/biossíntese , Animais , Células Epidérmicas , Epiderme/metabolismo , Feminino , Heterópteros/citologia , Heterópteros/ultraestrutura , Masculino , Pigmentos Biológicos/química , Pigmentos Biológicos/classificação
6.
J R Soc Interface ; 10(83): 20121065, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23516063

RESUMO

Many animals extract, synthesize and refine chemicals for colour display, where a range of compounds and structures can produce a diverse colour palette. Feather colours, for example, span the visible spectrum and mostly result from pigments in five chemical classes (carotenoids, melanins, porphyrins, psittacofulvins and metal oxides). However, the pigment that generates the yellow colour of penguin feathers appears to represent a sixth, poorly characterized class of feather pigments. This pigment class, here termed 'spheniscin', is displayed by half of the living penguin genera; the larger and richer colour displays of the pigment are highly attractive. Using Raman and mid-infrared spectroscopies, we analysed yellow feathers from two penguin species (king penguin, Aptenodytes patagonicus; macaroni penguin, Eudyptes chrysolophus) to further characterize spheniscin pigments. The Raman spectrum of spheniscin is distinct from spectra of other feather pigments and exhibits 17 distinctive spectral bands between 300 and 1700 cm(-1). Spectral bands from the yellow pigment are assigned to aromatically bound carbon atoms, and to skeletal modes in an aromatic, heterocyclic ring. It has been suggested that the penguin pigment is a pterin compound; Raman spectra from yellow penguin feathers are broadly consistent with previously reported pterin spectra, although we have not matched it to any known compound. Raman spectroscopy can provide a rapid and non-destructive method for surveying the distribution of different classes of feather pigments in the avian family tree, and for correlating the chemistry of spheniscin with compounds analysed elsewhere. We suggest that the sixth class of feather pigments may have evolved in a stem-lineage penguin and endowed modern penguins with a costly plumage trait that appears to be chemically unique among birds.


Assuntos
Plumas/química , Pigmentos Biológicos/química , Spheniscidae/fisiologia , Animais , Cor , Filogenia , Pigmentos Biológicos/classificação , Análise Espectral Raman , Spheniscidae/classificação
7.
J Microbiol Biotechnol ; 17(10): 1645-54, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18156780

RESUMO

The total methylotrophic population associated with rice plants from different cultivars was enumerated at three different stages: vegetative, flowering, and harvesting. The bacterial population in the leaf, rhizosphere soil, endophytic in the stem and roots, and epiphytic in the florets and grains were determined from four rice cultivars, Il-mi, Nam-pyeoung, O-dae, and Dong-jin, sampled from three different field sites. The methylotrophic bacteria isolated on AMS media containing 0.5% methanol as the sole carbon source uniformly showed three distinct morphologies, which were recorded as separate groups and their distribution among the various samples was determined using the ecophysiological index. The growth stage at the time of sampling had a more significant effect on the methylotrophic population and their distribution than the field site or cultivar. A similar effect was also observed for the PPFMs, where their population in different plant parts increased from V10 to R4 and then decreased towards stage R9. A canonical discriminant analysis of the PPFM population from different parts of rice showed clear variations among the cultivars, sampled sites, and growth stages, although the variations were more prominent among the growth stages.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Oryza/microbiologia , Análise de Variância , Bactérias/crescimento & desenvolvimento , Técnicas de Tipagem Bacteriana , Contagem de Colônia Microbiana , Ecossistema , Grão Comestível/microbiologia , Methylobacterium/classificação , Methylobacterium/crescimento & desenvolvimento , Methylobacterium/isolamento & purificação , Pigmentos Biológicos/classificação , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Caules de Planta/microbiologia , Microbiologia do Solo
8.
Gene ; 399(1): 26-32, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17590287

RESUMO

At present, molecular bases of spectral tuning in rhodopsin-like (RH2) pigments are not well understood. Here, we have constructed the RH2 pigments of nocturnal Tokay gecko (Gekko gekko) and diurnal American chameleon (Anolis carolinensis) as well as chimeras between them. The RH2 pigments of the gecko and chameleon reconstituted with 11-cis-retinal had the wavelengths of maximal absorption (lambda(max)'s) of 467 and 496 nm, respectively. Chimeric pigment analyses indicated that 76-86%, 14-24%, and 10% of the spectral difference between them could be explained by amino acid differences in transmembrane (TM) helices I-IV, V-VII, and amino acid interactions between the two segments, respectively. Evolutionary and mutagenesis analyses revealed that the lambda(max)'s of the gecko and chameleon pigments diverged from each other not only by S49A (serine to alanine replacement at residue 49), S49F (serine to phenylalanine), L52M (leucine to methionine), D83N (aspartic acid to asparagine), M86T (methionine to threonine), and T97A (threonine to alanine) but also by other amino acid replacements that cause minor lambda(max)-shifts individually.


Assuntos
Lagartos/metabolismo , Pigmentos Biológicos/química , Pigmentos Biológicos/classificação , Opsinas de Bastonetes/química , Opsinas de Bastonetes/classificação , Substituição de Aminoácidos , Animais , Evolução Molecular , Lagartos/genética , Dados de Sequência Molecular , Filogenia , Pigmentação , Pigmentos Biológicos/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Opsinas de Bastonetes/genética , Análise Espectral
9.
Infection ; 35(3): 126-33, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17565452

RESUMO

Over the past several decades, the appearance of pink-pigmented bacteria in clinical specimens has gone from being a microbiologic curiosity in the clinical laboratory to the recognition of these aerobic microorganisms as etiologic agents of human disease, most notably bloodstream infections. Advances in the fields of molecular taxonomy and phylogenetics indicate that at least four distinct genera and eight different species are associated with clinical infections in susceptible patient populations. However, these bacteria are slow growing and present multiple diagnostic challenges to the microbiology laboratory including culture, isolation, and identification to species rank. This article provides a current review of these unusual non-fermentative chromogenic bacteria including their disease spectrum, taxonomy, and laboratory identification. The review also highlights the pitfalls or shortcomings we currently have in our knowledge of these microbes and their disease-producing capabilities.


Assuntos
Bacilos e Cocos Aeróbios Gram-Negativos/classificação , Bacilos e Cocos Aeróbios Gram-Negativos/patogenicidade , Infecções por Bactérias Gram-Negativas/diagnóstico , Classificação , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Pigmentos Biológicos/classificação
10.
Photochem Photobiol ; 81(6): 1343-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15901211

RESUMO

Circular dichroism (CD) was used to study the structure of oxyblepharismin (OxyBP), the photoreceptor chromophore for the photophobic response of the blue form of Blepharisma japonicum. Both the chromophore associated to its native protein and the free chromophore in ethanol solution were investigated. CD spectra in the far-UV range indicate that OxyBP induces a slight increase in the alpha-helix content of the protein matrix. CD spectra in the near-UV and visible region of the spectrum show that OxyBP adopts a chiral conformation with a preferential geometry not only when associated to its protein matrix, but also when isolated and dissolved in ethanol. This experimental result is related to the existence of a high-energy interconversion barrier between two enantiomeric structures of the molecule and discussed on the basis of an asymmetric biosynthesis of its precursor, blepharismin.


Assuntos
Perileno/análogos & derivados , Células Fotorreceptoras/química , Animais , Cilióforos/química , Dicroísmo Circular , Estrutura Molecular , Perileno/química , Perileno/classificação , Fotorreceptores Microbianos/química , Fotorreceptores Microbianos/classificação , Pigmentos Biológicos/química , Pigmentos Biológicos/classificação , Ligação Proteica , Conformação Proteica , Proteínas de Protozoários/química , Espectrofotometria Ultravioleta
13.
Can J Microbiol ; 50(10): 853-60, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15644900

RESUMO

The effect of mechanical wounding or foliar diseases caused by Sclerotinia homoeocarpa or Rhizoctonia solani on the epiphytic yeast communities on creeping bentgrass and tall fescue were determined by leaf washing and dilution plating. Total yeast communities on healthy bentgrass and tall fescue leaves ranged from 7.9 x 103 to 1.4 x 105 CFU.cm-2 and from 2.4 x 103 to 1.6 x 104 CFU.cm-2, respectively. Mechanically wounded leaves (1 of 2 trials) and leaves with disease lesions (11 of 12 trials) supported significantly larger communities of phylloplane yeasts. Total yeast communities on S. homoeocarpa infected or R. solani infected bentgrass leaves were 3.6-10.2 times and 6.2-6.4 times larger, respectively, than the communities on healthy leaves. In general, healthy and diseased bentgrass leaves supported larger yeast communities than healthy or diseased tall fescue leaves. We categorized the majority of yeasts as white-pigmented species, including Cryptococcus laurentii, Cryptococcus flavus, Pseudozyma antarctica, Pseudozyma aphidis, and Pseudozyma parantarctica. The percentage of pink yeasts in the total yeast community ranged from 2.6% to 9.9% on healthy leaves and increased to 32.0%-44.7% on S. homoeocarpa infected leaves. Pink-pigmented yeasts included Rhodotorula glutinis, Rhodotorula mucilaginosa, Sakaguchia dacryoidea, and Sporidiobolus pararoseus. Foliar disease significantly affected community size and composition of epiphytic yeasts on bentgrass and tall fescue.


Assuntos
Agrostis/microbiologia , Ascomicetos/fisiologia , Festuca/microbiologia , Doenças das Plantas/microbiologia , Rhizoctonia/fisiologia , Leveduras/fisiologia , Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Contagem de Colônia Microbiana , Cryptococcus/classificação , Cryptococcus/isolamento & purificação , Ecossistema , Pigmentos Biológicos/biossíntese , Pigmentos Biológicos/classificação , Pigmentos Biológicos/isolamento & purificação , Folhas de Planta/microbiologia , Rhodotorula/classificação , Rhodotorula/isolamento & purificação
14.
J Exp Bot ; 52(362): 1805-10, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11520868

RESUMO

Photosynthetic pigment composition and photosystem II (PSII) photochemistry were characterized during the flag leaf senescence of wheat plants grown in the field. During leaf senescence, neoxanthin and beta-carotene decreased concomitantly with chlorophyll, whereas lutein and xanthophyll cycle pigments were less affected, leading to increases in lutein/chlorophyll and xanthophyll cycle pigments/chlorophyll ratios. The chlorophyll a/b ratio also increased. With the progression of senescence, the maximal efficiency of PSII photochemistry decreased only slightly in the early morning (low light conditions), but substantially at midday (high light conditions). Actual PSII efficiency, photochemical quenching and the efficiency of excitation capture by open PSII centres decreased significantly both early in the morning and at midday and such decreases were much greater at midday than in the early morning. At the same time, non-photochemical quenching, zeaxanthin and antheraxanthin contents at the expense of violaxanthin increased both early in the morning and at midday, with a greater increase at midday. The results in the present study suggest that a down-regulation of PSII occurred in senescent leaves and that the xanthophyll cycle plays a role in the protection of PSII from photoinhibitory damage in senescent leaves by dissipating excess excitation energy, particularly when exposed to high light.


Assuntos
Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Triticum/fisiologia , Senescência Celular , Clorofila/metabolismo , Regulação para Baixo , Metabolismo Energético , Fluorescência , Luz , Complexos de Proteínas Captadores de Luz , Luteína/metabolismo , Fotoquímica , Complexo de Proteínas do Centro de Reação Fotossintética/química , Complexo de Proteína do Fotossistema II , Pigmentos Biológicos/química , Pigmentos Biológicos/classificação , Pigmentos Biológicos/metabolismo , Folhas de Planta , Temperatura Ambiente , Triticum/metabolismo , Xantofilas/metabolismo
15.
Proc Biol Sci ; 268(1475): 1489-93, 2001 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-11454293

RESUMO

Many species of deciduous trees display striking colour changes in autumn. Here, we present a functional hypothesis: bright autumn coloration serves as an honest signal of defensive commitment against autumn colonizing insect pests. According to this hypothesis, individuals within a signalling species show variation in the expression of autumn coloration, with defensively committed trees producing a more intense display. Insects are expected to be averse to the brightest tree individuals and, hence, preferentially colonize the least defensive hosts. We predicted that tree species suffering greater insect damage would, on average, invest more in autumn-colour signalling than less troubled species. Here, we show that autumn coloration is stronger in species facing a high diversity of damaging specialist aphids. Aphids are likely to be an important group of signal receivers because they are choosy, damaging and use colour cues in host selection. In the light of further aspects of insect and tree biology, these results support the notion that bright autumn colours are expensive handicap signals revealing the defensive commitment of individual trees to autumn colonizing insect pests.


Assuntos
Adaptação Fisiológica , Árvores/fisiologia , Animais , Afídeos/fisiologia , Cor , Interações Hospedeiro-Parasita/fisiologia , Filogenia , Pigmentos Biológicos/classificação , Pigmentos Biológicos/metabolismo , Folhas de Planta/fisiologia , Estações do Ano , Árvores/parasitologia
16.
Arch Microbiol ; 175(5): 384-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11409549

RESUMO

The lungs of cystic fibrosis patients are frequently colonized by Pseudomonas aeruginosa, which produces high-affinity fluorescent peptidic siderophores, pyoverdines. Three pyoverdines which differ in their peptide chain and are easily differentiated by isoelectric focusing exist, only one being produced by a given strain. P. aeruginosa isolates from cystic fibrosis patients of a German hospital were analyzed by sequential, pulse-field gel electrophoresis (PFGE) and for pyoverdine production and type. Only producers of type I and type II pyoverdine were found. There was a perfect correlation between the type of pyoverdine produced and the clonality determined by PFGE. PFGE clone C, the most prevalent among cystic fibrosis patients, and found in an aquatic environment, produced type II pyoverdine. Pyoverdine-negative mutants seemed to increase as a function of the lung colonization time, but retained the capacity to take up pyoverdines. Most isolates that took up type II pyoverdine were also able to utilize type I pyoverdine as judged by growth stimulation experiments. No correlation was observed between the loss of pyoverdine production and mucoidy.


Assuntos
Fibrose Cística/microbiologia , Mutação/genética , Oligopeptídeos , Pigmentos Biológicos/química , Pigmentos Biológicos/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Fibrose Cística/complicações , Eletroforese em Gel de Campo Pulsado , Humanos , Focalização Isoelétrica , Faringe/microbiologia , Pigmentos Biológicos/classificação , Pigmentos Biológicos/isolamento & purificação , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/microbiologia , Sideróforos/química , Sideróforos/classificação , Sideróforos/isolamento & purificação , Sideróforos/metabolismo
17.
J Agric Food Chem ; 49(4): 1971-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11308355

RESUMO

Red-colored plants in the family Amaranthaceae are recognized as a rich source of diverse and unique betacyanins. The distribution of betacyanins in 37 species of 8 genera in the Amaranthaceae was investigated. A total of 16 kinds of betacyanins were isolated and characterized by HPLC, spectral analyses, and MS. They consisted of 6 simple (nonacylated) betacyanins and 10 acylated betacyanins, including 8 amaranthine-type pigments, 6 gomphrenin-type pigments, and 2 betanin-type pigments. Acylated betacyanins were identified as betanidin 5-O-beta-glucuronosylglucoside or betanidin 6-O-beta-glucoside acylated with ferulic, p-coumaric, or 3-hydroxy-3-methylglutaric acids. Total betacyanin content in the 37 species ranged from 0.08 to 1.36 mg/g of fresh weight. Simple betacyanins (such as amaranthine, which averaged 91.5% of total peak area) were widespread among all species of 8 genera. Acylated betacyanins were distributed among 11 species of 6 genera, with the highest proportion occurring in Iresine herbstii (79.6%) and Gomphrena globosa (68.4%). Some cultivated species contained many more acylated betacyanins than wild species, representing a potential new source of these pigments as natural colorants.


Assuntos
Lectinas/isolamento & purificação , Pigmentos Biológicos/isolamento & purificação , Plantas/química , Acilação , Betacianinas , Cromatografia Líquida de Alta Pressão , Lectinas/classificação , Espectrometria de Massas , Pigmentos Biológicos/classificação , Lectinas de Plantas
18.
J Biochem Biophys Methods ; 45(2): 221-9, 2000 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-10989138

RESUMO

Silica gel, aluminium oxide, diatomaceous earth, polyamide, cyano, diol and amino plates have been tested for their capacity to separate the color pigments of six chili powders of different origin by both adsorption and reversed-phase thin-layer chromatography. The plates were evaluated at 340 and 440 nm wavelengths. Best separation of color pigments was obtained on impregnated diatomaceous earth layer using acetone-water 17:3 v/v eluent. It was found that the pigment composition of chili powders showed marked differences. Principal component analysis employed for the classification of the chili powders according to their pigment composition indicated that these differences can be used for the determination of the similarity or dissimilarity of the chili powders.


Assuntos
Capsicum/química , Cromatografia em Camada Delgada/métodos , Análise de Alimentos/métodos , Plantas Medicinais , Cromatografia em Camada Delgada/estatística & dados numéricos , Análise de Alimentos/estatística & dados numéricos , Pigmentos Biológicos/análise , Pigmentos Biológicos/classificação , Pós , Espectrofotometria
19.
Crit Rev Food Sci Nutr ; 40(3): 173-289, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10850526

RESUMO

Pigments are present in all living matter and provide attractive colors and play basic roles in the development of organisms. Human beings, like most animals, come in contact with their surroundings through color, and things can or cannot be acceptable based on their color characteristics. This review presents the basic information about pigments focusing attention on the natural ones; it emphasizes the principal plant pigments: carotenoids, anthocyanins, and betalains. Special considerations are given to their salient characteristics; to their biosynthesis, taking into account the biochemical and molecular biology information generated in their elucidation; and to the processing and stability properties of these compounds as food colorants.


Assuntos
Pigmentos Biológicos/fisiologia , Antocianinas/biossíntese , Antocianinas/classificação , Betalaínas , Carotenoides/biossíntese , Carotenoides/classificação , Humanos , Pigmentos Biológicos/classificação , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/classificação
20.
J Prosthet Dent ; 80(2): 204-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9710823

RESUMO

PURPOSE: This literature review provides information about pigments used for facial and somatoprostheses. MATERIAL: This information includes common pigment and index names and numbers, lightfastness categories, chemical type and class, and the chemical formulas of the common pigments used in maxillofacial prosthetics. CONCLUSION: It can be deduced from this review that the pigments used with silicone elastomers do exhibit a color change, and that a color change is to be expected.


Assuntos
Prótese Maxilofacial , Pigmentos Biológicos/química , Pigmentação em Prótese , Elastômeros de Silicone/química , Humanos , Luz , Pigmentos Biológicos/classificação , Pigmentos Biológicos/efeitos da radiação , Elastômeros de Silicone/efeitos da radiação , Luz Solar
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