• Applied Biological Chemistry
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• v.40 no.4
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• pp.294-300
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• 1997

As a part of basic investigation for utilizing by-products derived from marine food processing more effectively as a food source, refining of viscera oil of squid caught off Newzealand were investigated. In the process of refining, degumming with 3% of phosphoric acid at $60^{\circ}C$ for 30 min was effective in removing phosphatides, and optimal condition to neutralize was treating with 0.6% excess of 20% sodium hydroxide solution at $80^{\circ}C$ for 20 min. Bleaching was optimized by adding 10% activated clay and treating for $100^{\circ}C$ for 20 min under vacuum, and deodorizing was done by steam destillation at $180^{\circ}C$ for 60 min under 4 torr of vacuum. Acid value, peroxide value and chromaticity of refined squid viscera oil were 0.20, 0.8 meq/kg and 0.019, respectively. The ratio of polyenoic acid composition to saturated acid composition of refined squid viscera oil was 1.28 and its major fatty acids were 16 : 0, 18 : In-9, 20 : 5n-3 and 22 : 6n-3.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.284-289
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• 1993

The effect of oil refining processes-degumming, alkali-refining, bleaching and deodorizing-on oil characteristics and oxidation stability of sesame oil were investigated. The colors(L, a, b) of samples were markedly changed and their peroxide and acid values were decreased, while the other characteristics of samples were not changed during refining stages. The L values of alkali-refined, bleached and deodorized sesame oils were largely decreased and their a values were increased due to browning reaction during the storage at $70^{\circ}C$. The colors of crude and degmmed sesame oils were very stable and their peroxide, free fatty acid and conjugated dienoic acid values were slowly increased. Volatile carbonyl compounds formed by oxidation were increased during the storage at $70^{\circ}C$. The results indicated that refining processes did not affect the sesame oil characteristics but decreased the oxidation stability of sesame oil.

• Journal of Microbiology and Biotechnology
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• v.30 no.7
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• pp.1051-1059
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• 2020

Overproduction and accumulation of melanin in the skin will darken the skin and cause skin disorders. So far, components that can inhibit tyrosinase, a melanin synthase of melanocytes, have been developed and used as ingredients of cosmetics or pharmaceutical products. However, most of existing substances can only inhibit the biosynthesis of melanin while melanin that is already synthesized and deposited is not directly decomposed. Thus, their effects in decreasing melanin concentration in the skin are weak. To overcome the limitation of existing therapeutic agents, we started to develop a substance that could directly biodegrade melanin. We screened traditional fermented food microorganisms for their abilities to direct biodegrade melanin. As a result, we found that a kimchi-derived Pediococcus acidilactici PMC48 had a direct melanin-degrading effect. This PMC48 strain is a new strain, different from P. acidilactici strains reported so far. It not only directly degrades melanin, but also has tyrosinase-inhibiting effect. It has a direct melanin-decomposition effect. It exceeds existing melanin synthesis-inhibiting technology. It is expected to be of high value as a raw material for melanin degradation drugs and cosmetics.

• Ocean and Polar Research
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• v.23 no.4
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• pp.389-394
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• 2001

During austral summer 1998 we examined the impacts of artificial UV-B and solar radiation on chlorophyll a content and fresh weight of four species of Antarctic red algae namely, Georgiella confluens, Iridaea cordata, Pantoneura plocamioides and Porphyra endiviifolium. These subject species were taken in consideration of clear demarcations of their vertical distribution and classified as shallow water group (Iridaea and Porphyra) and deep water group (Georgiella and Pantoneura). When irradiated with artificial UV-B at the irradiance of $2.0Wm^{-2}$ the shallow water inhabitants were much more resistant than the algae from deep water the fresh weight of which was reduced by 40-50% relative to control apart from loss of pigmentation. Direct solar radiation was lethal to the deep water group with a sign of complete bleaching whereas the shallow water group did not show any change in the physiological parameters. We were unable to discriminate difference in the algal sensitivity between UV-filtered and UV-transparent treatments since samples tested were either all unaffected or dead. Spectrophotometric measurements of methanolic extracts revealed a strong absorption peak in the UV range in the shallow water group of algae, Iridaea and Porphyra, but not in the deep water counterparts. Species difference in sensitivity to artificial UV-B and solar radiation is discussed in relation to biochemical and morphological characteristics and the role of the radiation in the algal vertical distribution is suggested from ecological perspective.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.418-426
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• 2015

Total phenol contents, total flavonoid contents and antioxidant activity of 70% methanol, 70% ethanol and chloroform-methanol (CM, 2:1, v/v) extracts from onion (Allium cepa L.) peels were studied. The $IC_{50}$ values of DPPH (2,2-diphenyl-1-picrylhydrazyl) radical and ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] radical scavenging activity in 70% ethanol extract were remained to be lowest followed by 70% methanol extract and CM extract. And the total phenol content ($113.56{\pm}0.86mg\;CAE/g$), total flavonoid content (49.63 mg QE/g) and ferric reducing antioxidant power value were also found to be the highest. In contrast, 70% methanol extract possessed the strongest antioxidant activity by ${\beta}$-carotene bleaching assay. CM extract displayed the lowest antioxidant activity compared with other extracts. Onion peels exhibited strong antioxidant activity and abundant phytochemicals, which could be used in a various food products to add phytochemicals and promote good health.

• Journal of the Semiconductor & Display Technology
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• v.4 no.1 s.10
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• pp.29-34
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• 2005

Tungsten oxide($WO_{3}$) is suitable to materials for photochromic window in the visible region. The resistivities of CdS, $WO_{3}$, and $WO_{3}$/CdS films prepared by thermal evaporation method were $4.61\times 10\^{3}$, $7.59\times10^{3}$, and $6.29\times10^{3}$ $\omega$ cm. And x-ray diffraction patterns of CdS, $WO_{3}$/CdS films showed a preferred orientation of hexagonal(002), and the monoclinic(020) structure, respectively. The optical transmission were measured that the cut-on wavelength were 510nm, 380nm for CdS and $WO_{3}$ films respectively, and the transmission spectrum of $WO_{3}$/CdS was shifted into the visible region. Photoluminescence(PL) spectra showed the two peaks at 2.8 eV and 3.2 eV for the as-grown sample($WO_{3}$/CdS ($500{\AA}$), but the other sample($WO_{3}$/CdS ($1000{\AA}$)) had a peak energy value of 2.8 eV. The photochromism of $WO_{3}$/CdS films showed that the excitation of electron-hole pairs and subsequent coloration is shifted into visible-light range. And the spectral behavior of coloration turned out to be proportional to the excited electron-hole pairs creation rate of CdS film. This result is interpreted in terms of charge carrier injection from the CdS-layer into the $WO_{3}$ films. We found a value of about 2.8 eV of $WO_{3}$/CdS film which is somewhat higher than peak energy of 2.54 eV using CBD prepared by Bechinger et. al.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.4
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• pp.56-63
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• 2010

Microcrystalline cellulose (MCC) was prepared from Miscanthus in this study. Two pulping methods, soda pulping and alkaline sulfite pulping were applied as a pretreatment process. After pulping, two different bleaching processes such as $ClO_2$ treatment followed by $H_2O_2$ treatment and $O_3$ treatment followed by $H_2O_2$ treatment were carried out. Two concentration of $H_2SO_4$, 47% and 57% were applied to the purified Miscanthus cellulose as a acid hydrolysis process to make MCC. The crystallinity index and morphological properties of the produced MCC were evaluated with X-ray diffractometer and scanning electron microscopy. The MCC originated from the soda pulping sample showed the higher crystallinity index than that originated from the alkaline sulfite pulping sample. The two stages of treatmen twith $O_3$ and $H_2O_2$ resulted in the higher purified cellulose products.

• Ceramist
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• v.22 no.3
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• pp.281-300
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• 2019

Surface enhanced Raman scattering (SERS) was first discovered in 1974 by an unexpected Raman signal increase from Pyridine adsorbed on rough Ag electrode surfaces by the M. Fleishmann group. M. Moskovits group suggested that this phenomenon could be caused by surface plasmon resonance (SPR), which is a collective oscillation of free electrons at the surface of metal nanostructures by an external light source. After about 40 years, the SERS study has attracted great attention as a biomolecule analysis technology, and more than 2500 new papers and 500 review papers related to SERS topic have been published each year in recently. The advantages of biomaterials analysis using SERS are as follows; ① Molecular level analysis is possible based on unique fingerprint information of biomolecule, ② There is no photo-bleaching effect of the Raman reporters, allowing long-term monitoring of biomaterials compared to fluorescence microscopy, ③ SERS peak bandwidth is approximately 10 to 100 times narrower than fluorescence emission from organic phosphor or quantum dot, resulting in higher analysis accuracy, ④ Single excitation wavelength allows analysis of various biomaterials, ⑤ By utilizing near-infrared (NIR) SERS-activated nanostructures and NIR excitation lasers, auto-fluorescence noise in the visible wavelength range can be avoided from in vivo experiment and light damage in living cells can be minimized compared to visible lasers, ⑥ The weak Raman signal of the water molecule makes it easy to analyze biomaterials in aqueous solutions. For this reason, SERS is attracting attention as a next-generation non-invasive medical diagnostic device as well as substance analysis. In this review, the principles of SERS and various biomaterial analysis principles using SERS analysis will be introduced through recent research papers.

• Korean Journal of Health Education and Promotion
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• v.13 no.2
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• pp.167-183
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• 1996

Human teeth vary widely in color. Practitioner and patients are concerned with preventing and correcting discolored or dark teeth to achieve and maintain stain-free, white teeth. Tooth brushing cannot alter tooth color but it can remove adhering films and stains. The esthetics of natural dentition can be improved by bleaching and this process can be applied to intrinsically and extrinsically stained teeth. The need for a brighter, more attractive smile has made rapid growth in the market for tooth whiteners. There is no doubt these products work as whiteners, at least on mild to moderate stains, but the safety of these products are unclear. In this experiment, the effect of tooth whitener application on the color and microhardness of extracted human enamel was measured. RMS, RMT and NWT were used as tooth whiteners, and tooth paste(ETQ) and hydrogen peroxide solution(HPO) were used as controls. 35 caries-free extracted human molars were embedded and polished with the exposed enamel diameter of 4 mm. The tooth whiteners and control agents were applied according to the manufacturers' instructions or clinically simulated procedures for eight weeks, and measurements were repeated every two weeks. Value(L＊) difference was measured using Differential Colorimeter(Model TC-6FX, Denshoku Co., Japan), and microhardness was measured using microhardness tester(Mitsuzawa Seiki Co., Japan). The results were as follows; 1. After application of agents for eight weeks, the Vickers hardness increased significantly in the ETQ, RMS and RMT application group(p〈0.01), and that decreased significantly in NWT application group(p〈0.01), but in HPO application group there was no significant change. The change in microhardness was greatest in NWT application group(p〈0.01). 2. After application of tooth whiteners and controls for eight weeks, the value change of toothpaste application group was significantly lower than those of other agents groups(p〈0.01), and there was no significant difference in value(L＊) change among tooth whitener groups(p〉0.01). 3. The application of tooth paste and paste type tooth whitener made gradual value change, but hydrogen peroxide gel type tooth whitener and hydrogen peroxide solution made rapid value change during initial application period.

• Culinary science and hospitality research
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• v.14 no.4
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• pp.441-455
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• 2008

The primary objective of this research was to investigate the recognition, preference and the present using status of yam for the data which will be useful to make consumers intake more yams and to develop more yam processed products. Almost all respondents who had eaten yams liked it, and Andong people eat more yams than Daegu people. About 60.3% respondents who like yams cited the reason was "it's good for health". Among the respondents who had eaten yams recognized it as nutritional, healthful, and diet food compared with the respondents who had not eaten yams. Recognition degree was higher when the preference for yams was higher. Among the types of yam processed cooking, according to intake ratio, yam juice formed 38%, followed by bleaching(17%) etc. Among the types of yam processed food, powdered tea formed 34%, followed by yam gruel(24%), yam drinks(19%) etc. It showed that respondents eat very few foods made from yams and yam processed food. As for purchasing yam processed food, the result showed that the main concerns of the respondents were the "ratio of yams"(24.9%), followed by "tastes"(21.3%) etc. The largest group (29.4%) of the respondents suggested that the improvements of yams were "diversification of the processed food" followed by "improved taste"(26.4%) while 62.5% of the respondents indicated that they would buy yams after its improvement, which showed a good prospect of yam processed food.