• Applied Biological Chemistry
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• v.39 no.3
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• pp.245-248
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• 1996

Thermal stability of the major color component, cyanidin 3-glucoside, isolated from Korean pigmented rice (Oryza sativa var. Suwon 415) were investigated to explore possible application of value-added natural colors as food additives. The anthocyanin showed red and blue color with maximum absorption peaks at 511 nm and 572 nm in acidic (pH 2.0) and alkaline (pH 9.0) buffer solutions, respectively, and the thermal degradation reactions were carried out with different temperature ranges at $50{\sim}95^{\circ}C$. Degree of degradation was determined with UV/Vis spectra which indicate characteristic absorption patterns with sharp isosbestic points at 350 nm (pH 2.0), and 275, 310, and 405 nm (pH 9.0). Thus the reaction follows simple first-order kinetics. The anthocyanin was very stable against heat at acidic pH and relatively stable at alkaline pH with half-life values of 50.3 hr and 0.6 hr at $70^{\circ}C$, respectively. The activation energies and Arrhenius frequency factors of the pigment were 26.9 kcal $mol^{-1}\;and\;6.0{\times}10^{11}\;s^{-1}$, at pH 2.0, and 15.2 kcal $mol^{-1}\;and\;1.4{\times}10^{6}\;s^{-1}$, pH 9.0, and respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.391-397
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• 2014

Anthocyanins are water-soluble plant pigments that give rise to the red, purple, or blue colors observed in many crops. Especially purple pigment of colored rice represent biological activities has been an increased interest, due to the functional meal as a staple food. These health benefits have been attributed to antioxidant property of anthocyanin. However, there have been little genetic source for development of new and various colored rice variety. A recently developed new variety, 'Jungmo1020', showed an unique characteristic of blue color of rice grain hull. We identified the pigment petunidin-3-O-glucoside (Pt-3-G) as a major compound with a value of $176.3{\pm}2.3mg/100g$ (68.3%) from 80% MeOH with 1% HCl extracts by UPLC/MS/MS. The content of Pt-3-G in the extracts using a solvent of 100% MeOH with 1% HCl was the highest with the values of $183.8{\pm}2.5mg/100g$. In addition, these extracts showed excellent antioxidatative activities by DPPH and ABTs assay.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.3
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• pp.67-74
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• 1982

The effect of various pH levels, temperatures. organic acids, inorganic salts, metal ions on the stability of the anthocyanins pigment (pH 3.7) from the juice of raspberries were investigated. Initial absorption of total anthocyanin was decreased as pH increased from 1.0 to 7.0. Total amount of anthocyanin reached the highest at pH 3.7 and least at pH 7.0. The total anthocyanin content decreased rapidly with the increasing temperature. Many organic acids were found to enrich and stabilize the color density at 520nm in anthocyanin solution (pH 3.7). The hyperchromic effect of saturated n-carboxylic acid increased in the following order; formic acid> acetic acid>n-butyric acid>propionic acid. On the polycarboxylic acid, especially, malic acid showed 550$\sim$930% higher than control group. On the inorganic salts (0.5M), sodium perchlorate had the most hyperchromic effect and followed by sodium sulfate>sodium chloride>sodium phosphate, monobasic. Among the metal ions, both aluminium ion and cupric ion much more accelerated the anthocyanins degradation as compared with other metal ions.

• The Korean Journal of Mycology
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• v.20 no.1
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• pp.65-71
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• 1992

The two isolates of Streptomyces antagonistic to Phytophthora nicotianae var. parasitica and Fusarium oxysporum f. sp. vasinfectum were identified as based on the morphological, cultural and physiological characteristics on various culture media. Spore chains of St-11 isolate was rectus-flexibilis(RF), whereas the other isolate, St-20, was shown rectinaculum-apertum(RA). Spore surface of St-11 isolate was smooth, while St-20 was spiny. Aerial mycelia of the two isolates were all gray color and growing conditions on media were good as a whole. Any soluble pigment was not shown in cultivation of the two isolates. Stoll isolate showed negative response on starch hydrolysis and gelation liquefaction, whereas St-20 isolate was positive on starch hydrolysis and a negative on gelatin reaction. Stoll isolate was identified as Streptomyces bikiniensis and St-20 Streptomyces echinoruber, respectively.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.345-351
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• 2005

To access the natural products of uncultured microorganisms, we constructed and screened the metagenomic DNA libraries by using a cosmid vector and DNA inserts isolated directly from soil. Initial screening of the libraries in Escherichia coli resulted in the isolation of several clones that produce a dark brown color when grown in LB medium. One of the positive clones, designed pYS85C, was transposon mutagenized and the DNA surrounding the transposon insertions in cosmids that no longer conferred the production of brown pigment to E. coli was sequenced. Annotation of the pYS85C sequence obtained from the transposon mutagenesis experiment indicated a single 393 amino acid open reading frame (ORF) with a molecular mass of about 44.5 kDa, predicted to be a 4-hydroxyphenylpyruvate dioxygenases (HPPDs), was responsible for the observed brown pigment. In a BLAST search against deposited sequence, the translated protein from this ORF showed moderate-level identity (>60%) to the other known HPPDs and was most conserved in the C-terminal region of the protein. These results show that genes involved in natural product synthesis can be cloned directly from soil DNA and expressed in a heterologous host, supporting the idea that this technology has the potential to provide novel natural products from the wealth of environmental microbial diversity and is a potentially important new tool for drug discovery.

• The Journal of the Korea Contents Association
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• v.14 no.2
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• pp.181-191
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• 2014

In the past, making IR photography needed somewhat complicated process, so its application fields were limited. However, it has become easy to make IR photography with advanced digital technology, so it is expected that the fields of IR photography and existing limit due to difficult making process will be expanded. Therefore, in this study, it is decided that the need of IR standard chart which allows us to manage exposure and tone of IR photography for scientific purpose will increase. Two methods were used to make IR standard chart. First method is to use aluminum. When aluminum has oxide coating through anodic oxidation, it has high durability, corrosion resistance and heat resistance. Also, IR reflectance of aluminum can be controlled in some degree depending on the thickness of oxide coating. Second method is to use pigments. Yellow 10P150 pigment is used for the brightest patch. This pigment is appropriate in this study due to high heat resistance and IR reflectance. Carbon black is used for the darkest patch. Carbon black absorbs much IR, and its color is not faded by any source of light. IR reflectance is adjusted elaborately by mixing two pigments. Finally, 6 patches are selected with consideration for actual IR reflectance of patches. As a result, IR reflectance of random subjects can be known approximately and IR photographs can have appropriate contrast with the IR standard chart.

• Journal of Conservation Science
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• v.31 no.4
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• pp.331-339
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• 2015

This study were conducted the particle-size analysis on 57 blue pigments to understand the step distribution characteristics of blue pigments made out of Azurite by using Malvern's Mastersizer 2000. As the result, most of the conventional blue pigments in Korea, Japan, and Chinese showed good granularity step separation except for few, and the smaller the particle, the more the Span value increased and the wider the granularity distribution range. On the basis of Friedman and Sanders's Grain size, most of the pigments were sand size to silt size. 72.2% of B-100 was clay size and 2.5% of A-14 was gravel size. Even the same components can differ by the grain size directly affecting the important property such as color formation, oil absorption, specific gravity, usability, etc. so the information about the granularity distribution would be used for basic data to deal with natural pigments.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.789-796
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• 2012

This study attempted to investigate the characteristics of Superjami, which had a high C3G (cyandin-3-glucoside) content by comparing it with common rice (Ilpum) and black rice (Heougjinju, Suwon 415) for their components and physio-chemical characteristics. There were no significant differences in the water content, however there were significant differences in crude protein and crude fat in the order of Ilpum < Superjami < Heougjinju. As for the morphological characteristics of grains, it had been learned that Superjami was heavier and longer than the common rice, moreover Superjami had bigger seeds. As for the hardness of grains, the longer the time of steeping, the more decreased their hardness was at large. In the case of color, they showed significant differences in all the L, a, and b values of grains and flours. As a result of the experiment of pigment elution after steeping of the rice flours at $20^{\circ}C$ and $40^{\circ}C$, the longer the time steeping, the more increased the pigment elution became. The values are bigger with Heougjinju and Superjami than with Ilpum. As for the elution pH after rice steeping, the longer the time of steeping, the lower pH all the assays tended to have. As a result of the analysis of the total polyphenol contents of Ilpum, Heougjinju, and Superjami, it had turned out that the total polyphenol contents of Heougjinju and Superjami are 1.2 times as high as Ilpum, a common rice, and that Superjami is significantly higher than Heougjinju. As a result of the experiment of DPPH radical scavenging ability, there are significant differences among the assays in the order of Superjami > Heougjinju > Ilpum. Futher, it has turned out that Superjami has a higher DPPH radical scavenging ability than Heougjinju. Consequently, it can be stated that Superjami has a strong anti-oxidative ability. Thus, we should more precisely grasp the cooking characteristics of Superjami, which is in the state of brown rice, via comparing it with a common brown rice, and also provide opportunities to apply Superjamii to more foods by studying its starch characteristics in addition to its grain and flour properties.

• 보존과학연구
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• s.32
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• pp.75-87
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• 2011

The materials analysis is important in conservation science for cultural assets since conservators can make appropriate decision of treatment and environment through understanding manufacturing, period and materials. Palsapumdo is the painting of Palsapum which was given by Yi Sun-shin from the emperor Shinjong in The Ming Dynasty. Palsapumdo painted with various pigments on the fabric has remained to adhere a sheet of lining paper. In this study, we carried out the fiber identification about the fabric and lining paper and the analysis of the pigments. This study identified a fabric and a lining paper and analised pigments for the painting. As a result of fabric analysis, it was confirmed as cotton because ribbon twists and shape of kidney bean in a cross section. After the analysis of lining paper, color changed to yellow by Graff "C" staining tests, and had short fiber and tracheid. Therefore, it is supposed to be a paper which is made of conifer pulp. In addition, the results of SEM-EDS, the pigments are indicated as Orpiment($As_2S_3$), Minium($Pb_3O_4$), Hematite($Fe_2O_3$), Emeraldgreen ($C_2H_3As_3Cu_2O_8$), Ultramarine [$2(Na_2O{\cdot}Al_2O_3{\cdot}2SiO_2){\cdot}Na_2S_2$], talc[$Mg_3Si_4O_{10}(OH)_2$], bariumsulfate($BaSO_4$) and brass.

• Korean Journal of Food Science and Technology
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• v.6 no.4
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• pp.209-213
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• 1974

Pigments were extracted by aqueous acetone from the boiled canned oyster colored during storage and then the components were separated by thin layer chromatography. Totally eleven pigments could be isolated including one yellow, one red, five orange or reddish orange and four green components, and their UV-visible spectra were measured. It can be envisioned from the electronic spectral study and color reaction on the indivisual pigments isolated from the brown acetone extracts that the green pigments as well as most of the yellow orange ones may be porphyrin derivatives originated probably from the chlorophyll and some of the orange pigments contains ketocarotenoids. In particular, the pigment of band 8 which is expected to be pheophytin a or its derivatives and the carotenoid band 7 seem to be the major pigment. The close resemblance of the chromatogram of the colored muscle extract to that of the viscera suggests that the brown coloring material is probably originated from the viscera pigments.