• Applied Microscopy
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• v.39 no.1
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• pp.41-48
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• 2009

We investigated the morphological characteristics of the pearlescent pigment by using scanning electron microscope, energy dispersive X-ray spectrometry and thermal analyzer. The result is that the shape of pigment is platy polygonal form through observing the pearlescent pigment by the scanning electron microscope. The size of pigment is various and not formed in standardized size or shape. The pigment flakes were measured about from $30{\mu}m$ to $300{\mu}m$. The tip of the piece of pigment is pointed shape or angled. The result of observing them by the scanning electron microscope in magnifying high power is that the edge and the lateral face of them is an round form and the measurement of thickness is about $9{\mu}m$. As well using the high magnification scanning electron microscope, the surface of the pigment flake observed like rugged as coating with the $TiO_2$ element, the diameter of the coating particle is around 60 nm, then the coating particle consists of granular substance. Analysis of the configuration elements of pearlescent pigment using by the energy dispersive X-ray spectrometry is that O, Si, C, Na, Ca, Ti, Zn detected in the surface of pigment and its lateral face identifies similar components. In thermal analysis, there are no contained quantity differences between them in beginning from $100^{\circ}C$ to $800^{\circ}C$ showing thermal analysis, 1.1% out of contained quantity reduced at $115^{\circ}C$, 1.7% dropped at $416^{\circ}C$, and 1.9% decreased at $797^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.352-359
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• 1996

Stabilities of purple sweet potato (PSP) anthocyanin pigment on pH, sugars, organic acids, metal ions, ascorbic acid and light were investigated to provide the basic information for utilization of PSP as a potential source of anthocyanin pigment. pH has a marked influences on the color of the PSP anthocyanin solution; i.e., at low pH the color of PSP was more intense and stable. It showed characteristic bathochromic shift as the pH of the solution increased. Among the sugars tested, glucose showed a protective effect on the color of PSP pigment to raise the color intensity and stability, while sucrose and fructose showed an adverse effect. Addition of organic acids greatly increased the stability of PSP anthocyanin pigment. Citric acid was found to be the most effective followed by malic. tartaric, and succinic acids. Most metal ions except $Al^{3+}$ and $Cd^{2+} were found to be detrimental effect on the stability of PSP pigment. Ascorbic acid degraded PSP pigment considerably, and had a synergistic effect with oxygen on the pigment degradation. The effect of light on PSP pigment was found to be very deleterious. The pigment degradation can be minimized by shielding the light from the pigment solution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1047-1052
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• 2001

The pigment content in meju fermented by a Monascus species with different materials was studied. The relations between growth of M. pilosus and pigment production were positive and the correlation coefficient associated with this relationship was determined to be : r = 0.9879. Pigments produced by M. purpureus and M. pilosus were composed of 9 and 8 bands, respectively. One kind of them was yellowish, whereas the others were reddish. Total pigment levels in rice meju fermented by M. purpureus and M. pilosus were 335.25 and 1428.90$\mu\textrm{g}$/g, respectively. Pigment levels in the mejus fermented at 3$0^{\circ}C$ showed higher than those at 20 and 4$0^{\circ}C$. The order of pigment content in meju was polished rice > germinated brown rice > wheat > brown rice > waxy brown rice > germinated waxy brown rice. Pigment production by M. pilosus was higher than that of M. purpureus. Pigment content in rice meju prepared by adding 10% seed culture was highest, and pigment content of granulated rice was higher than that of powdered rice. Pigment production was not desirable in soybean meju fermented by seed culture, whereas the pigment levels in meju by adding 10% powdered rice and 10% powdered rice seed meju increased by 23.0 ~75.0 $\mu\textrm{g}$/g.

• Korean Journal of Construction Engineering and Management
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• v.1 no.2 s.2
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• pp.63-70
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• 2000

Since inorganic pigment, among admixtures used for cement composites, can raise the esthetic value of a building due to its effect of coloring, it can be assumed that the quantity consumed is expected to increase in connection with the recent trend of emphasizing the beautiful sights of the city. We carried out a flow test by changing the mix proportion of the cement mortar mixed with an inorganic pigment, water-cement ratio and pigment mixing ratio in order to present the basic materials for utilizing colored cement mortars. In construction by exploring the effect of inorganic pigments on the workability of cement mortar. In case of red pigment mortar and yellow pigment mortar, the workability was found to be rapidly decreased. To secure proper workability, it is necessary to increase the amount of mixing water, or to use superplasticizer. In case of green pigment mortar, however, it recorded $-2.4{\~}6.9{\%}$, showing that there was almost no change in flow. In case of black pigment mortar, it was also confirmed that there is no need to consider workability.

• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.383-389
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• 2000

Stabilities to heat, pH, light were investigated about isolated red color pigment from the Korean Lithospermum erythrorhizon. The extracted pigment, acetylshikonin was stable heating at 40∼80$\^{C}$ for 1∼2 hours, hut it was specially unstable on the storage above 55$\^{C}$. The extracted pigment, acetylshikonin was stable on the sunlight under the red and green filters but unstable under the yellow and blue filters. The extracted pigment, acetylshikonin was stable under the pH of 4∼8 but unstable under the pH above 10. The extracted pigment, acetylshikonin was stable under the KCl and NaCl at concentration of 10$\^$-1/Mole. The pigment was very unstable under the CaCl$_2$, FeCl$_3$, CoCl$_2$, AlCl$_3$ and MnCl$_2$ at concentration of 10$\^$-1/Mole. The red pigment, acetylshikonin was stable under citric acid and acetic acid at concentration of 1 Mole. Especially, acetic acid was effective for the stability of the pigment.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.111-115
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• 2002

To produce yellow pigment selectively, mutants were induced from Monascus anka Nakazawa et Sato IFO 4478 (KCCM 11832 strain), and their characteristics were evaluated. Five kinds of auxotrophic mutants which required amino acids for growth and pigmentation, were isolated through a series of mutagenic treatments. Especially, asparagine auxotroph Y7 produced high ratio of yellow pigment. This mutant showed all the morphological characteristics of Monascuceae but the shape of colony and the diameter of conidia. Mutant Y7 was propagated by sexual reproduction more often than asexual reproduction, which could be effective in production of pigments. Yellow pigment produced extracellularly by the mutant Y7 was more soluble in polar solvents such as ethanol and water than in nonpolar solvents. Its productivity of yellow pigment was 2.2 times higher in the mutant Y7 than in parents. In addition, its yellow pigment showed characteristics of maximum absorption at 373 nm. Moreover, the hue of pigment produced by the mutant Y7 was bright yellow, and it was stable through the subculture over 10 generations.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.219-225
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• 2009

A bacterial strain, JE-34, producing a high concentration of red pigment was isolated from a sediment in East China Sea. It was identified as Zooshikella sp. JE-34 based on the 16S rRNA gene sequence analysis. The red pigment was purified by solvent extraction and HPLC was identified as prodigiosin-like compound. Nutritional and cultural conditions were optimized for the production of prodigiosin-like pigment in the flask level. Optimal culture conditions were at initial medium pH $6.0{\sim}7.0$, $30^{\circ}C$ and 4 days incubation. For carbon and, nitrogen sources were soluble starch and malt extract.

• Parasites, Hosts and Diseases
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• v.54 no.4
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• pp.393-397
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• 2016

Low parasitemic condition in malaria remains a diagnostic challenge; as the available diagnostic methods failed to detect. Currently, hemozoin (Hz) pigment is gaining attention in the diagnosis of malaria. The major drawback is ease of detection of Hz in routine practice. A pilot study was conducted to evaluate the role of Hz pigment and to compare the performance of quantitative buffy coat assay (QBC) and PCR in such conditions. Clinically suspected cases of malaria were examined by both Giemsa stain and immunochromatographic test (ICT). Samples positive by ICT and negative by Giemsa stain were further examined by nested PCR targeting 18S rRNA and QBC for the presence of malaria parasites and pigments. Thirty blood samples fulfilled the inclusion criteria out of which 23 were Plasmodium vivax (Pv), 4 Plasmodium falciparum (Pf), and 3 mixed (Pv and Pf) by immunochromatographic test. Twenty-one out of 30 (70%) were positive by nested PCR in comparison to 25/30 (83%) by QBC. Samples containing both malaria parasites and Hz pigment by QBC completely showed concordance with the PCR result. However, 61% of total samples containing only Hz pigment were observed positive by PCR. Hz pigment remains an important tool for malaria diagnosis. Identification of leukocytes containing pigments by QBC not only indicates recent malarial infections but also puts light on severity of the disease. QBC assay is a rapid, highly sensitive, and cost-effective method to detect malaria parasites and Hz pigment especially in low parasitemic conditions.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.3
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• pp.303-316
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• 2018

In this study, I investigated the applicability of fluorescein-derived xanthene dyes to fluorescent pigment and the controllability of the optical properties of manufactured pigments. Eosin Y (D&C Red No.22) and phloxine B (D&C Red No.28) were mainly used as a dye to prepare the pigment. Dyes dissolved in a solvent were poured into a powder dispersed in the solvent, then dried and pulverized to fabricate the pigments. Optical characteristics related with fluorescence of the prepared pigment were measured. The optical properties of pigments were varied depending on the solvent used, content of the dye in the pigment, and the ratio of dyes when more then two dyes were mixed. According to the experiment result, it seems that some of the dyes attached to the powder showed fluorescence while the rest did not contribute to it. From the result of pigment washing experiment to explore the binding (or interaction) strength and characteristics of the powder-dye system constituting the pigment, it seems that there are two or more different interactions existing in the pigment system, one of which is relatively stronger than the solvent-dye interaction.

• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.23-29
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• 2010

Pigment concentrates with violet-red color and sweet taste were obtained from purple-fleshed sweet potato(PFSP) using ethyl alcohol and water. Extract from general potato(GP) were used as a control. The relative stability of PFSP pigment concentrate(PFSPPC) in a storage test over 15 days was confirmed in the order of dark > fluorescence > sun-light irradiation. The relative stability of GP pigment concentrate(GPPC) in a storage test over 15 days was confirmed in the order of sun-light > fluorescence > dark storage. The RRP of PFSPPC was higher than that of GPPC, but the color strength of GPPC was 1/2 that of PFSPPC. Treatment of PFSPPC with aluminum potassium sulfate(0.2~0.3%, w/w) best improved its stability. The improved RRPs of PFSPPC were 45.16~47.31% in sun light irradiation, 55.91~60.22% in fluorescence irradiation, and 76.34~75.97% in dark storage conditions. In substituting aluminum potassium sulfate for chitosan, an amount of 0.2~0.3%(w/w) was suitable, giving similar results in improving pigment stability for all concentrates tested. Also, freeze-dried PFSPPC powder was manufactured as a substitute for dextrin, and also as a substitute for chitosan to the extent of 0.25%(w/w). The results of storage stabilite for freeze-dried PFSPPC and GPPC powder over 15 days, irradiation were, PRRs of 74.47~89.36% and 61.54~76.92%, respectively. The stability improving effect of freeze dried PFSPPC powder was confirmed by the results of storage experiments at various conditions. The use of freeze-dried PFSPPC powder was therefore confirmed to be an effective treatment for general foods.