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Blue Pigment (blue + pigment)
Selected AbstractsIdentification of Candidate Amino Acids Involved in the Formation of Blue Pigments in Crushed Garlic Cloves (Allium sativum L.)JOURNAL OF FOOD SCIENCE, Issue 1 2009Jungeun Cho ABSTRACT:, The color-forming ability of amino acids with thiosulfinate in crushed garlic was investigated. We developed reaction systems for generating pure blue pigments using extracted thiosulfinate from crushed garlic and onion and all 22 amino acids. Each amino acid was reacted with thiosulfinate solution and was then incubated at 60 °C for 3 h to generate pigments. Unknown blue pigments, responsible for discoloration in crushed garlic cloves (Allium sativum L.), were separated and tentatively characterized using high-performance liquid chromatography (HPLC) and a diode array detector ranging between 200 and 700 nm. Blue pigment solutions exhibited 2 maximal absorbance peaks at 440 nm and 580 nm, corresponding to yellow and blue, respectively, with different retention times. Our findings indicated that green discoloration is created by the combination of yellow and blue pigments. Eight naturally occurring blue pigments were separated from discolored garlic extracts using HPLC at 580 nm. This suggests that garlic discoloration is not caused by only 1 blue pigment, as reported earlier, but by as many as 8 pigments. Overall, free amino acids that formed blue pigment when reacted with thiosulfinate were glycine, arginine, lysine, serine, alanine, aspartic acid, asparagine, glutamic acid, and tyrosine. Arginine, asparagine, and glutamine had spectra that were more similar to naturally greened garlic extract. [source] CORRELATION BETWEEN SPECTRAL, SEM/EDX AND ELECTROCHEMICAL PROPERTIES OF MAYA BLUE: A CHEMOMETRIC STUDY*ARCHAEOMETRY, Issue 6 2009A. DOMÉNECH Visible spectra, composition from SEM/EDX and solid-state electrochemical data are correlated for a set of 12 Maya Blue samples from different archaeological sites of Campeche and Yucatán (Mexico). In addition to indigo and dehydroindigo, indirubin and other possibly indigo-type compounds can be detected in Maya Blue samples. Application of hierarchical cluster analysis techniques allows similarity relationships to be established between samples from different sites, confirming prior results which suggest that the preparation of Maya Blue pigment evolved with time during the Maya culture following a ramified scheme. [source] Chemistry and some biological effects of model melanoidins and pigments as Maillard intermediatesMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 12 2006Fumitaka Hayase Abstract Various pigments were formed in the D -xylose-glycine reaction system. Blue pigments (Blue-M1 and Blue-M2) and red pigments (Red-M1 and Red-M2) were generated in the Maillard reaction. Blue-M2 is presented to have been generated by the reaction between Blue-M1, which involved two pyrrolopyrrole structures as the major blue pigment, and di- D -xyluloseglycine. We identified red pigments as the isomers of addition compounds of D -xyluloseglycine to condensated compound between pyrroropyrrole-2-carbaldehyde and pyrrole-2-carbaldehyde compounds. These pigments have polymerizing activities, suggesting that they are important Maillard reaction intermediates through the formation of melanoidins. Blue-M1 as well as melanoidins effectively suppressed the peroxidation of linoleic acid. The scavenging activity toward Blue-M1 on hydroxyl and DPPH radicals was also as strong as that of melanoidins. Furthermore, Blue-M1 prevents the oxidative cell injury. Therefore, Blue-M1 will be an antioxidant which protects against the oxidative stress in biological systems. Melanoidins induced IFN-, mRNA and IL-12 mRNA expressions in spleen cells exposed to allergen and in macrophage-like J774.1 cells, respectively. These findings suggest that melanoidins have suppressive effect on allergic reaction as a novel physiological effect. [source] Meroterpenoid Pigments from Albatrellus flettii (Basidiomycetes),EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 10 2007Barbara Koch Abstract The pigments responsible for the blue colour of the North American polypore Albatrellus flettii have been isolated and their structures elucidated by spectroscopic methods. Albatrellin, a dimeric meroterpenoid with a furylbenzoquinone chromophore, is accompanied by its 16-hydroxy and 16-oxo derivatives. The latter has recently been described as grifolone B from a Japanese collection of A. caeruleoporus. Based on the idea that albatrellin is formed in nature by oxidative coupling of a grifolinquinone with the furan derivative cristatin, the blue pigment was synthesized in vitro. The reaction could be applied to the synthesis of several analogues.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Application of white-beam X-ray microdiffraction for the study of mineralogical phase identification in ancient Egyptian pigmentsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2007P. A. Lynch High-brightness synchrotron X-rays together with precision achromatic focusing optics on beamline 7.3.3 at the Advanced Light Source have been applied for Laue microdiffraction analysis of mineralogical phases in Egyptian pigments. Although this task is usually performed using monochromatic X-ray diffraction, the Laue technique was both faster and more reliable for the present sample. In this approach, white-beam diffraction patterns are collected as the sample is raster scanned across the incident beam (0.8,µm × 0.8,µm). The complex Laue diffraction patterns arising from illumination of multiple grains are indexed using the white-beam crystallographic software package XMAS, enabling a mineralogical map as a function of sample position. This methodology has been applied to determine the mineralogy of colour pigments taken from the ancient Egyptian coffin of Tjeseb, a priestess of the Apis bull dating from the Third Intermediate to Late period, 25th Dynasty to early 26th Dynasty (747 to 600 BC). For all pigments, a ground layer of calcite and quartz was identified. For the blue pigment, cuprorivaite (CuCaSi4O10) was found to be the primary colouring agent with a grain size ranging from ,10 to 50,µm. In the green and yellow samples, malachite [Cu2(OH)2CO3] and goethite [FeO(OH)] were identified, respectively. Grain sizes from these pigments were significantly smaller. It was possible to index some malachite grains up to ,20,µm in size, while the majority of goethite grains displayed a nanocrystalline particle size. The inability to obtain a complete mineralogical map for goethite highlights the fact that the incident probe size is considerably larger than the grain size. This limit will continue to improve as the present trend is toward focusing optics approaching the diffraction limit (,1000× smaller beam area). [source] Identification of Candidate Amino Acids Involved in the Formation of Blue Pigments in Crushed Garlic Cloves (Allium sativum L.)JOURNAL OF FOOD SCIENCE, Issue 1 2009Jungeun Cho ABSTRACT:, The color-forming ability of amino acids with thiosulfinate in crushed garlic was investigated. We developed reaction systems for generating pure blue pigments using extracted thiosulfinate from crushed garlic and onion and all 22 amino acids. Each amino acid was reacted with thiosulfinate solution and was then incubated at 60 °C for 3 h to generate pigments. Unknown blue pigments, responsible for discoloration in crushed garlic cloves (Allium sativum L.), were separated and tentatively characterized using high-performance liquid chromatography (HPLC) and a diode array detector ranging between 200 and 700 nm. Blue pigment solutions exhibited 2 maximal absorbance peaks at 440 nm and 580 nm, corresponding to yellow and blue, respectively, with different retention times. Our findings indicated that green discoloration is created by the combination of yellow and blue pigments. Eight naturally occurring blue pigments were separated from discolored garlic extracts using HPLC at 580 nm. This suggests that garlic discoloration is not caused by only 1 blue pigment, as reported earlier, but by as many as 8 pigments. Overall, free amino acids that formed blue pigment when reacted with thiosulfinate were glycine, arginine, lysine, serine, alanine, aspartic acid, asparagine, glutamic acid, and tyrosine. Arginine, asparagine, and glutamine had spectra that were more similar to naturally greened garlic extract. [source] Lapis lazuli as unexpected blue pigment in Iranian Lâjvardina ceramicsJOURNAL OF RAMAN SPECTROSCOPY, Issue 6 2003Philippe Colomban Abstract Raman analysis of an ancient ewer (Iran, 13th century) belonging to the Lâjvardina blue glazed ceramics shows that the ultramarine colour results from the unexpected deposit of a lazurite-rich slip at the interface between the body and a cobalt-containing lime-rich glaze. This confirms the use of Lâjvard (lapis lazuli) as reported in an old alchemist's treatise (Abű'l Qâsim Kâshâni, 14th century). Copyright © 2003 John Wiley & Sons, Ltd. [source] Comparison of genuine (1851,1852 AD) and forged or reproduction Hawaiian Missionary stamps using Raman microscopyJOURNAL OF RAMAN SPECTROSCOPY, Issue 6 2002Tracey D. Chaplin The rare and valuable Hawaiian Missionary stamps from the Tapling Collection held at the British Library were analysed using Raman microscopy and shown to be printed with an ink composed of Prussian blue. Blue particles dispersed between the paper fibres of the stamps and present as optical brighteners were identified to be lazurite or the synthetic equivalent, ultramarine blue. Each cancellation or postmark, where present, is composed of carbon, vermilion, iron(III) oxide or a madder-like organic pigment. The Raman analysis also showed that microscopic repair work on stamps can be identified. The genuine stamps were compared with 13 forged Hawaiian Missionary stamps, printed in the early 20th century, and with a set of eight reproduction items printed in 1985, from the Royal Philatelic Society London. Raman analysis of the forged stamps showed that the ink used is different from that of the genuine stamps, being a mixture of Prussian blue and ultramarine blue, or an organic blue pigment. Analysis of the 1985 reproduction stamps showed that they were printed with modern phthalocyanine blue ink, on paper coated with a yellow organic pigment to simulate aged paper. This analysis provides an invaluable and non-destructive method for assisting in drawing a distinction between fraudulent or reproduction material and the genuine article. Copyright © 2002 John Wiley & Sons, Ltd. [source] Chemistry and some biological effects of model melanoidins and pigments as Maillard intermediatesMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 12 2006Fumitaka Hayase Abstract Various pigments were formed in the D -xylose-glycine reaction system. Blue pigments (Blue-M1 and Blue-M2) and red pigments (Red-M1 and Red-M2) were generated in the Maillard reaction. Blue-M2 is presented to have been generated by the reaction between Blue-M1, which involved two pyrrolopyrrole structures as the major blue pigment, and di- D -xyluloseglycine. We identified red pigments as the isomers of addition compounds of D -xyluloseglycine to condensated compound between pyrroropyrrole-2-carbaldehyde and pyrrole-2-carbaldehyde compounds. These pigments have polymerizing activities, suggesting that they are important Maillard reaction intermediates through the formation of melanoidins. Blue-M1 as well as melanoidins effectively suppressed the peroxidation of linoleic acid. The scavenging activity toward Blue-M1 on hydroxyl and DPPH radicals was also as strong as that of melanoidins. Furthermore, Blue-M1 prevents the oxidative cell injury. Therefore, Blue-M1 will be an antioxidant which protects against the oxidative stress in biological systems. Melanoidins induced IFN-, mRNA and IL-12 mRNA expressions in spleen cells exposed to allergen and in macrophage-like J774.1 cells, respectively. These findings suggest that melanoidins have suppressive effect on allergic reaction as a novel physiological effect. [source] Oyster greening by outdoor mass culture of the diatom Haslea ostrearia Simonsen in enriched seawaterAQUACULTURE RESEARCH, Issue 10 2001V Turpin Abstract Oyster greening was first described in the seventeenth century as a natural phenomenon. However, it has recently been discovered that the diatom Haslea ostrearia Simonsen causes greening by synthesis of a blue pigment designated as ,marennine'. This phenomenon, which involves massive proliferation of H. ostrearia in oyster ponds, was not understood or controlled by oyster farmers in the Marennes-Oléron region (Atlantic coast of France). As greening oysters improved their market value, they tried to develop empirical methods to guarantee oyster fattening and improve profits. In this context, the present study investigated the feasibility of mass culture of diatoms outdoors in 10-m3 ponds, using enriched seawater. Different biotic and abiotic parameters were monitored daily to determine the influence of the day,night temperature range. After 8 days, H. ostrearia was the dominant diatom species (66%), reaching a mean cell concentration of 2 × 105 cell mL,1 and a marennine concentration of 3.4 mg L,1. Although intensive greening was obtained, further studies are required to optimize the production stages before this technology can be transferred to oyster farmers. [source] EVIDENCE FOR THE USE OF EGYPTIAN BLUE IN AN 11TH CENTURY MURAL ALTARPIECE BY SEM,EDS, FTIR AND SR XRD (CHURCH OF SANT PERE, TERRASSA, SPAIN)ARCHAEOMETRY, Issue 2 2010A. LLUVERAS The present study shows the analysis performed on pigment samples taken from Sant Pere (Terrassa, Catalonia, Spain), a remarkable church built in the Romanesque style. On the basis of the results obtained from the analysis, an interesting discussion arises after finding evidence of Egyptian blue in one of the samples, a discovery that was not expected due to the time period of the samples. The pigments were identified by the combined use of FTIR and SEM with an EDS facility. For the blue pigment, since the EDS and FTIR analyses suggested the possible presence of cuprorivaite, micro-XRD experiments using synchrotron radiation were run. [source] THE OCCURRENCE OF PALYGORSKITE IN THE YUCATÁN PENINSULA: ETHNO-HISTORIC AND ARCHAEOLOGICAL CONTEXTS*ARCHAEOMETRY, Issue 2 2009M. SÁNCHEZ DEL RÍO Palygorskite is a rare clay mineral used by the ancient Mayas for fabricating the Maya blue pigment and for other purposes. It seems to have been obtained from a restricted area in the Yucatán peninsula where important archaeological sites are found. Geological samples from different localities in this area show a high content in palygorskite, indicating that this clay is widespread in Yucatán. Combining structural, morphological, compositional and geochemical methods, we analysed the common characteristics of Yucatecan palygorskites, and compared them with palygorskites from other origins around the world. These results can be used for defining a fingerprint of Yucatecan palygorskite to be used in provenance studies of archaeological artefacts, in particular the Maya blue pigment. [source] True blue football fan: Tattoo reaction confined to blue pigmentAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 1 2010Corinne Yoong ABSTRACT A tattoo reaction which appeared solely on the blue pigment of a 6-month old red and blue football club tattoo of an ardent fan was investigated. The patient was otherwise asymptomatic and no other abnormality was detected on full physical examination. Histology revealed a florid sarcoidal granuloma reaction to blue pigment. Preliminary investigations for systemic sarcoidosis did not reveal any abnormality. The tattoo reaction flattened clinically with the institution of a short course of topical mometasone furoate 0.1% ointment and as the subject remained asymptomatic, close surveillance for the development of systemic sarcoidosis is to continue. The possibility of delayed type hypersensitivity is discussed. [source] Identification of Candidate Amino Acids Involved in the Formation of Blue Pigments in Crushed Garlic Cloves (Allium sativum L.)JOURNAL OF FOOD SCIENCE, Issue 1 2009Jungeun Cho ABSTRACT:, The color-forming ability of amino acids with thiosulfinate in crushed garlic was investigated. We developed reaction systems for generating pure blue pigments using extracted thiosulfinate from crushed garlic and onion and all 22 amino acids. Each amino acid was reacted with thiosulfinate solution and was then incubated at 60 °C for 3 h to generate pigments. Unknown blue pigments, responsible for discoloration in crushed garlic cloves (Allium sativum L.), were separated and tentatively characterized using high-performance liquid chromatography (HPLC) and a diode array detector ranging between 200 and 700 nm. Blue pigment solutions exhibited 2 maximal absorbance peaks at 440 nm and 580 nm, corresponding to yellow and blue, respectively, with different retention times. Our findings indicated that green discoloration is created by the combination of yellow and blue pigments. Eight naturally occurring blue pigments were separated from discolored garlic extracts using HPLC at 580 nm. This suggests that garlic discoloration is not caused by only 1 blue pigment, as reported earlier, but by as many as 8 pigments. Overall, free amino acids that formed blue pigment when reacted with thiosulfinate were glycine, arginine, lysine, serine, alanine, aspartic acid, asparagine, glutamic acid, and tyrosine. Arginine, asparagine, and glutamine had spectra that were more similar to naturally greened garlic extract. [source] MICRO-RAMAN SPECTROSCOPY CHARACTERIZATION OF DELLA ROBBIA GLAZES,ARCHAEOMETRY, Issue 4 2007M. SENDOVA Micro-Raman spectroscopy and the laser-induced transformation technique were used for systematic study of five coloured glazes on Saint John the Baptist (29 inch tondo), a majolica terracotta relief attributed to Luca Della Robbia and on permanent exhibit in The John and Mable Ringling Museum of Art. We suggest that ions in a lead silicate matrix, called ,lead ultramarine', could contribute to the famous Della Robbia blue colour, in addition to the effect of Co atoms as suggested previously by Pappalardo et al. (2004). The original yellow glaze contains lead(II) antimonate. The green is a mixture of the yellow and blue pigments, the brown contains hematite, and the white glaze contains tin dioxide as an opacifier. The use of lead oxide as a main fluxing agent is confirmed by laser-induced micro-crystallization. [source] | ||||||||||