• Journal of Ginseng Research
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• v.30 no.2
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• pp.82-87
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• 2006

Quantitative difference in five phenolic acids between white and red ginsengs was measured in this study. As the results, white ginseng has higher contents of cinnamic acid, quercetin and p-coumaric acid than red ginseng. Maltol was mainly included in red ginseng. These five compounds were recently reported to have tyrosinase inhibitory effects. These reports led us to investigate the de-pigmenting effect of ginseng products. In our examination of effect on tyrosinase activity, UV-protection and melanin production in melan-a cells, ethyl acetate traction of white ginseng extract and cinnamic acid showed potent de-pigmenting properties. The results indicated that white ginseng might be useful as skin whitening material and cinnamic acid proved to be one of active ingredient.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.1-7
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• 1999

The grain rot of caused by Bukholderia glumae was fist reported in japan in 1955 and then reported in other countries as well as in Korea in 1986. The pathogen causes both seedling and grain rot of rice but it cannot attack any other parts of adult rice plant. Bacterial colonies grow slowly, and are circular and greyish white. The causal bacterium is Gram-negative and rod shape with 1-3 polar flagella, and produce a diffusible yellow-greenish nonfluorescent pigment on King's medium B. Biochemical characteristics such as negative in arginine dehydrolase, oxidase reaction and nitrate reduction and positive in lecithinase, and the utilization of L-arginine and inositol are useful in differentiation of this from other nonfluorescent bacteria pathogenic to rice. This pathogenic bacterium had belonged to the genus of Pseudomonas but recently was transferred to the new genus Burkholderia on the basis of physiological characteristics and DNA-DNA hybridization data. However, other characteristics such as colony heterogenicity or colonial variation after subcultures, phytotoxin, secreting antibiotics, and relationship between yellow greenish pigment production and pathogenicity need to be clarified more. To develop an effective control strategy for this disease, understanding of detailed life cycle of the disease and critical environmental factors affecting disease development is prerequisite. Although 5,435 ha of rice paddy in Korea was infested during 1998, there is no exact estimation of yield losses and distribution of the pathogen. The review will focus on recent progress on the understanding of the bacteriological and ecological characteristics of the causal bacterium and control means of the disease.

• 보존과학연구
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• s.24
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• pp.131-152
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• 2003

In ancient times, many kinds of different inorganic pigments were used as colorants for making objects. These pigments are still evidentin well known objects such as Danchung, mural painting and Buddhist painting. This study discusses the results obtained from an analysis of the pigments used on the Buddha pigments. The results can be briefly summarized as below; Firstly, the microcrystalline structures revealed on the cross section of analyzed pigments, samples of which were taken from various parts of Buddha pigments show that different sizes and shapes of pigment particle were used for different purposes such as coloring, toning of the pigments. The arrangement of pigments and their usages are varied according to the owner temples and the place where it was created. Secondly, a result of the analysis on the composition and structure of the pigments shows that the main components in their composition are: Red pigments - Red lead($Pb_3O_4$) and Cinnabar(HgS)Green pigments - Malachite[$CuCO_3$.$Cu(OH)_2$] and Prussian Blue[$Fe4(Fe(CN)_6)_2$]Gold pigments - pure gold(Au)Yellow pigments - Orpiment($A_s2S_3)White pigments - Lead Cyanamide[$Pb_3(CO_3)_2(OH)_2]Ultramarine pigments - Azulite[$Cu_3(CO_3)_2(OH)_2]Especially, we knew that pigments used on the Ssanggye temple not repaired to the artificial synthetic pigment

• Korean Journal of Veterinary Research
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• v.46 no.3
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• pp.275-278
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• 2006

A 7-month-old brown pig with a discoid and pedunculate mass measuring $14.0{\times}12.5{\times}2.5cm$ on the skin of the right shoulder was noted at the slaughter house in Jeju. The surface of mass approximately $7{\times}4cm$ was interfaced with skin. The color of mass with firm consistency was mainly black and partially white on cut surface. Histopathologically, numerous unencapsulated endocrine-like cellular nodules of epithelioid cell type with abundant intracytoplasmic black pigment, melanin, were occupied in dermis and subcutis. Most of nodules in deep dermis were surrounded by lightly pigmented spindle cells and loose fibrous tissues. Mitotic figures were infrequently observed. The overlying epidermis was hyperplastic due to the down-growth of rete peg. Based on the gross and histopathologic findings, this case was diagnosed as cutaneous melanoma. In our best knowledge, this is the first case of swine cutaneous melanoma in Korea.

• Conservation Science in Museum
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• v.6
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• pp.47-54
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• 2005

The elements of the pigments used on the wall painting in Ssangyeongchong (Tomb of Two Pillars) from Goguryeo in the Nampo area of Pyeongyang were analyzed to confirm their mineral compositions and features of the painting. Specifically, the non-destructive X-ray fluorescence spectrometer (XRF) was used. On the other hand, the mineral composition of the background and pigment layers were analyzed using an X-ray diffractometer (XRD). The results of these analyses suggested that the lips of the characters in the painting were painted with HgS, and their faces, painted with HgS(Cinnabar/ vermilion) mixed with CaCO₃. Note that lead white pigment [2PbCO₃·Pb(OH)₂] was found only on the bottom layer of the painting, indicating that the wall painting was likely to have been created using the Secco method.

• ALGAE
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• v.37 no.2
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• pp.163-174
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• 2022

Light-emitting-diodes (LEDs) are a lighting source useful for the precise evaluation of light quality effect on biological systems. Despite the importance of light spectra on the regeneration of land plant protoplasts ("naked cells"), this factor has not been tested yet on protoplasts from multicellular algae. This study reports on the effects of pure primary colors (red, blue, and green), dichromatic (red plus blue, RB, 1 : 2) and white LEDs on protoplast regeneration from male and female Undaria pinnatifida gametophytes. We also evaluated the effect of different light spectra on pigment composition (chlorophyll a, chlorophyll c, and fucoxanthine), and the light intensities under the best condition on the regeneration process. In the early stages, blue or RB LEDs increased the percentage of dividing female protoplasts, whereas red, blue, and RB LEDs enhanced that of dividing male protoplasts. In the later stages, RB LEDs showed a positive effect only on the percentage of multiple rhizoid-like protrusions (male gametophyte). They also increased the final area of both regenerated gametophytes. The LEDs did not affect pigment composition in female gametophytes. In male gametophytes, in contrast, they reduced chlorophyll c, while blue, RB, and green LEDs decreased fucoxanthin. Under RB LEDs, the optimal light intensity was 80 µmol photons m^-2 s^-1 for female gametophytes and 40 to 60 µmol photons m^-2 s^-1 for male gametophytes. Our results suggest that dichromatic LED illumination (red-blue) improves regeneration of U. pinnatifida gametophyte-isolated protoplasts. Thus, dichromatic LEDs might a suitable light source for enhancing protoplast regeneration in brown seaweeds.

• Conservation Science in Museum
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• v.16
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• pp.138-153
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• 2015

Wooden standing Bodhisattva in the collection of the National Museum of Korea (Bon 8239) was purchased as part of the museum's Central Asian collection during the Museum of Japanese Goverment General of Korea. The wooden statue exhibiting classical characteristics of Song Dynasty Buddhist sculptures is colored on the whone. The result of condition check for exhibition in 2014, it has severely damaged, with discoloring and exfoliation in color pigment and crack of wood observed in various areas. The object was therefore treated for conservation. A series of analysis were performed also at this time to determine the production technique and the materials, including testing of the X-ray penetration depth, X-ray fluorescence analysis and wood species analysis. This revealed that the statue was made by joining several separate pieces of wood. As for color pigments, the white pigment was either chalk (CaCO₃) or gypsum(CaSO₄·2H₂O), and the green pigment was emerald green (Cu(C₂H₃O₂)₂·3Cu(AsO₂)₂). The red pigment appeared to be lead red(Pb₃O₄) and the blue pigment was ultramarine blue (3Na₂O·3Al₂O₃·6SiO₂·2Na₂S). All the pigments were repainted in later eras. The analysis, indicated that the wood was derived from a tree of the genus Populus, family Salicaceae. The wooden standing Bodhisattva was repaired and reinforced with natural materials and was brought to a stable condition necessary for display.

• Journal of the Korean Ceramic Society
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• v.13 no.2
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• pp.24-30
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• 1976

To observe the influence of tetrahedral and octahedral preference of cations of Ni2+, Ti4+ upon the formation and the color development of the MgO-SnO2 spinel containing Ni2+ and Ti4+ ions, the gradual substitution of Ni2+ ions for Mg2+ ions and of Ti4+ ions for Sn4+ ions of the spinel in NiO-MgO-SnO2-TiO2 system was carried out. On samples prepared by calcining the oxide and basic carbonate mixtures at 130$0^{\circ}C$ for 1.5 hour, the X-ray analysis, measurement of reflectance and the test of their stability as a glaze pigment were also carried out. On samples prepared by calcining the oxide and basic carbonate mixtures at 130$0^{\circ}C$ for 1.5 hour, the X-ray analysis, measurement of reflectance and the test of their stabiality as a glaze pigment were also carried out. The results are summarized as follows. 1) As increasing the amounts of Ni2+ ions in the xNiO.(2-x)MgO.SnO2 system, spinel was not formed easily, and the mixed-spinel was formed in NiO.MgO.SnO2 of x=1 but the spinels was not formed completely in the range of x>1.5 2) The spinels was not more formed in NiO-MgO-TiO2 system than NiO-MgO-SnO2 system. Therefore, Ti4+ ions have strong octahedral preference than Sn4+ ions. The color changed the yellow region little. The mixed-spinel or non-spinel was formed easily NiO.TiO2, MgO.TiO2 of illmenite type as the gradual substitution of Ti4+ ions for Sn4+ ions. 3) The results of glaze test. The color changed from white through graish brown to brown as the gradual substitution of Ni2+ ions for Mg2+ ions in calcium-zinc glaze and calcium glaze, and from white through light yellowish beige to dull beige in tile glaze. Also, the color did not change generally as the gradual substitution of Ti4+ ions for Sn4+ ions in NiO-MgO-SnO2-TiO2 system.

• Economic and Environmental Geology
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• v.56 no.6
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• pp.899-909
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• 2023

In this study, the material scientific characteristics of Hobun pigments used as white inorganic pigment for traditional cultural heritage were identified according to the type of shell and calcination and evaluated the stability of the preservation environment. For the purpose of this, we collected 2 different types of Hobun pigments made by oyster and clam shell and its calcined products(at 1,150℃). Hobun pigments before calcined identified calcium carbonate such as calcite, aragonite but calcination derived changing main composition to portlandite and calcite. Results of FE-SEM showed characteristics microstructure for each shell but pigments after calcined observed porous structure. Porous granule highly caused oil adsorption according to increase specific surface area of pigments. In addition, the whiteness improved after calcined pigments compared to non-calcined pigments, and the color improvement rate of Hobun pigment (CS) which made of clam shell was higher. As a result of the accelerated weathering test, the Hobun pigment-colored specimen had a color difference value of less than 2 after the test, which was difficult to recognize with the naked eye. In particular, the color stability has improved as the color difference value of the Hobun pigment is smaller after calcined compared to before non-calcined pigment. However, it was confirmed that the stability of the painting layer was lower in the specimen after calcined pigment. For antifungal activity test, Aspergillus niger, Tyromyces palustris and Trametes versicolor were used as test fungi, and all pigments were found to have preventive and protective effects against fungi. Especially, the antifungal effect of the calcined pigment was excellent, which is due to the stronger basicity of the pigment.

• Journal of Conservation Science
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• v.36 no.1
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• pp.47-59
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• 2020

Scientific analysis was conducted to identify the paint pigments used in the Buseoksa Josadang murals. optical microscopy(OM), X-ray fluorescence(XRF), XRF mapping, scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDS), and Raman spectroscopy were performed to examine the pigments. The results confirmed that the Josadang murals consist of two paint layers wherein the pigments were distinct for most colors. It was estimated that celadonite, white clay, red ochre, cinnabar and minium, synthetic green pigment containing tin and zinc paratacamite, or botallackite were used in the upper layer. In addition, bone white, celadonite, red ochre, azurite, cinnabar or vermilion, and gold were identified in the lower layer. In addition, as Zn and Sn were detected in the green pigments extracted from the top layer of the paint, it is believed that Josadang murals were repainted over the original paint layer at some point after the 17th century. In addition, white pigments containing calcium phosphate were found in all the colors in the bottom layer, which is the original paint layer. These results are significant because this is the first time that white pigments are found in Korean traditional paintings. Additionally, the information revealed about the pigments in this study will serve as areference for the pigments used in the Goryeo period.