• Journal of the Korean Society of Safety
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• v.19 no.2
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• pp.104-111
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• 2004

The aim of this study was to investigate the influence of inorganic pigments on the physical properties of cement mortar. For this purpose, the compressive strength and absorption test were carried out on cement mortar imxed with inorganic pigments by changing the proportion of cement mortar, water-cement ratio, and ratio of pigment. The result of this study can be summarized as follows: the compressive strength of colored mortar rapidely increased in red and yellow mortar, as the mix ratio of pigment increased. In case of green and black mortar, however, the compressive strength decresed as the mix ratio incresed. In case of red and yellow mortar, the absorption of colored mortar increased as the mixing ratio increased, if the mean particle diameter of the pigment is small. In case of green and black mortar, the absorption ratio decreased as the mix ratio increased. After investigating the overall physical properties of colored mortar, it was confirmed that the proper mix ratio of pigment securing the properties of colored mortar was below 6% of the weight of the cement to be used.

• Journal of the Korean Ceramic Society
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• v.12 no.1
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• pp.29-36
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• 1975

This study was conducted to research the formation, color development and application for colored glazes of the spinel solid solutions of the green pigment. On specimens prepared by calcining the oxide and basic carbonate mixture at 1250℃ for 1.5 hour, the x-ray analysis, measurement of reflectance and the test of their stabiality as a glaze pigment were carried out. The results are summarized as follows 1) Each sample is composed of single spinel and not of mixture of spinel. 2) Formation of continuous soild solution, except for a few instances, pertaining to Vegard's law was confirmed by means of the x-ray analysis. 3) The more difference between absorption and reflectance lies, the lighter colors are. When the absorption occurs at the high-reflectance, the excitation purity becomes low. On the contrary when the absorption takes place at the low-reflectance, the excitation purity becomes low. On the contrary when the absorption takes place at the low-reflectance, the excitation purity is higher. 4) Colors obtained in the CdO-MgO-Cr2O3-Al2O3 system, as the amounts of Al3+ increased, change from green through brown to pink, and the absorption peak shifts towards violet region. 5) An increase in Co2+ in the CoO-MgO-Cr2O3-Al2O3 system, changes the color from blue green to dark blue. The excitation purity is higher, and the absorption peak shifts toward regions. 6) Colors are green in the NiO-MgO-Cr2O3 and CdO-MgO-Cr2O3 systems in general, but in the ZnO-MgO-Cr2O3 system brillant hue is not obtained. 70 According to the results of the colored glaze test, the spinels turn outto be stable as brilliant glaze pigment in the calcium-magnesia glaze.

• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.15-19
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• 1997

The stability of monascin yellow pigment isolated from Monascus purpureus was determined over a period of storage for the wide range of pH, various metal ions and antioxidants. The absorption maximum of monascin pigment was 385 nm. Monascin pigment was more stable in acid solutions than in alkaline (pH 9 and pH 11) during storage period. It was also observed the reduction of absorption was occur after 3 days storage. The stability of monascin pigment was not changed by adding the various metal ions of the concentration of 10-4 M, however, it was unstable by adding the Zn2+, Al3+ and Fe3+ of 103- M concentration. The antioxidants. BHA, BHT, cysteine and L-ascorbic acid, have no effects on the stability of monascin yellow pigment. Thus, it may be concluded that the monascin pigment is stable and useful food additives as the natural colorant except for the alkaline food and food containing the Zn2+, Al3+ and Fe3+.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1184-1187
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• 1999

The Gardenia jasminoides yellow pigment and converted pigments were completely separated by Amberlite XAD-4 column chromatography. These Pigments were gel filtrated on Sephadex LH-20 column chromatography. The characteristics of absorption spectra of eluate and fractionated pigments were investigated. The pigment converted by Lactobacillus plantarum showed a single blue color with an absorption peak at 588 nm and its molecular size was bigger than that of crocetin. The pigment, converted by Staphylococcus epidermidis, Showed blue-green color, which was composed of yellow color with an absorption peak at 418 nm and blue color at 588 nm. Molecular size of the yellow pigment was smaller than crocetin and that of blue color.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.319-323
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• 1998

Conversion of Gardenia jasminoides yellow pigment into blue-green pigment by 8 bacterial species was examed. Bioconversion pattern can be categorized into three types according to absorption spectra characteristics. The same pattern of the value of ${\Delta}E$ estimated by color differencemeter was also observed. Conversion rate by S. epidermidis was faster than other bacterial species. It took 16 hour for S. epidermidis to convert pigment at $37^{\circ}C$. Gardenia jasminoides yellow pigment and conversion pigment were completely separated by Amberlite XAD column chromatography with $H_2O-MeOH$ solvent system. Storage stability of the conversion pigment was better than Gardenia jasminoides yellow pigment.

• The Korean Journal of Food And Nutrition
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• v.6 no.4
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• pp.322-328
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• 1993

A study of general characteristics of acetone extracted pigment from the cell mass of Rhodospirillum rusrum DSM 467 was carried out for the development of natural food colorant. Through visible absorption scanning, it showed seven absorption peaks at 355, 410, 529, 624, 680 and 747nm, and it was shown to be yellow color. In acidic and neutral conditions, the color was yellow, while in the alkaline condition it was greenish yellow. This pigment was stable at pH range between 3.0~10.0, and below 4$0^{\circ}C$. In the presence of light and oxygen, the stability of pigment rapidly degraded and it became unstable in the presence of metal ions such as Cu2+, Al3+ and Fe3+. Through TLC analysis, it was shown to be composed of seven color fractions.

• Food Engineering Progress
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• v.13 no.4
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• pp.282-288
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• 2009

A dark brownish pigment from fruit body of Auricularia auricula was isolated and characterized in this report. The pigment was obtained with a yield of 0.61%(w/w) by alkaline extraction and subsequent purification steps. It showed the positive $FeCl_3$ test which was the indication of phenolic compounds. A synthetic melanin showed a similar spectrometric characteristics to the pigment extract regarding a characteristic UV absorption between 200-250 nm and infrared absorptions profiles in the finger print region including absorption peaks at 1701 and 1624 $cm^{-1}$. Its element analysis indicated that its atomic copmposition is close to that of DOPA melanin (eumelanin). With the result of its antioxidant activity in the TNBT (5-thio-2-nitrobenzoic acid) assay, we concluded that the dark brownish pigment from A. auricula is a melanin-like compound having a powerful antioxidative activity.

• Fashion & Textile Research Journal
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• v.8 no.2
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• pp.233-238
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• 2006

This research confirmed the chemical structure of Curcumine and Carthamin pigments whose pigments were separated and refined from the Curcuma longa and Carthamus Tinctorious which were natural dye using FT-IR, HPLC and so on. The cotton and the silk fabrics were dyed using a main pigment and then this research obtained the conclusion as it follows. The curcumine, the main pigment of Curcuma longa extracted from the mixed solvent of acetic anhydride and methanol ($CH_3OH$), had the maximum absorption wavelength at 504.0 nm and was confirmed as yellow natural pigment. The Carthamin, the main pigment of Carthamus Tinctorious extracted from the mixed solvent of dichloromethane and methanol, had the maximum absorption wavelength at 420.0nm. This pigment was confirmed as yellow natural pigment. The dyeing property of the main pigment about the silk fabrics was superior to that about the cotton in both the Curcuma longa and Carthamus Tinctorious, and the dyeing property of Carthamus Tinctorious was superior to that of Curcuma longa.

• Microbiology and Biotechnology Letters
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• v.24 no.6
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• pp.756-762
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• 1996

In order to develop the method for mass production of natural food colorant from Monascus anka, optimum cultivation conditions for producing red and yellow pigments by cultiva- ting the mold in a jar fermenter and their color characteristics were investigated. The mold produced red and yellow pigments both intracellularly and extracellularly. These pigments showed unique light absorption characteristics with maximum absorption of 494, 380, 506, and 388 nm for extracellular red pigment (ERP), extracellular yellow pigment (EYP), intracellular red pigment (IRP), and intracellular yellow pigment (IYP), respectively. Optimum conditions for producing red pigments were found to be temperature 30$\circ$C, initial pH 6.0, rice powder 3-5%, peptone 0.05%, magnesium sulfate 0.25%, aeration rate 0.1 vvm. Optimum temperature for producing yellow pigments was around 35$\circ$C which is higher than that of producing red pigments. The initial pH and rice powder concentration for producing yellow pigments were the same as those of producing red pigments. The higher concentration of nitrogen source and inorganic salt, aeration rate, the more the yellow pigments were produced. The optimum agitation speed was 100 - 300 rpm for pigment production.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.125-129
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• 1994

The acetone extracted pigment from the cell mass of Rhodophila globiformis DSM 161 was generally red. In a pH 5-6 condition, the color of pigment was red, while in p/h 7-9 condition it was yellowish red. The pigment was stable at pH range between 6.0-11.0 and below 4$0^{\circ}C$. In the presence of light and oxygen , the pigment was rapidly degraded and became unstable in the presence of metal ions such as Fe3++(1.0$\times$ 10-2M, 1.0$\times$10-3 M), Al3+ (1.0$\times$10-2 M, 1.0$\times$10-3 M) and Zn2+(1.0$\times$10-2 M). But in the presence of Zn2+ (1.0$\times$10-2M). But in the presence of Zn2+ (1.0$\times$10-3 M) it was very stable. Through visible absorption scanning ,it showed five sharp absorption peaks at 358 , 385, 494, 680 ad 748 nm with three shoulder peaks at 410, 466 and 522nm. On the results of TLC analysis , it was shown to be composed of seven color fractions.