• Journal of Life Science
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• v.11 no.6
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• pp.537-542
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• 2001

The concentrations of ${\gamma}$-aminobutyric acid in some Korean plants and mushrooms were investigated. ${\gamma}$-amino-butyric acid concentrations in Morus alba leaves, Cudrania tricuspidate leaves and fruits were 134.03, 104.13 and 120.99 mg/100g dry matter basis, respectively, ${\gamma}$-aminobutyric acid concentrations in Pleurotus ostreatus, Flammulina velutipes and Auricularia auricula were 93.44, 72.17 and 66.48 mg/100g dry matter basis. respectivley.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.4
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• pp.331-341
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• 2016

To evaluate the physicochemical and radiological properties of raw materials and by-products in domestic distribution, about 220 samples with 16 species were prepared. We measured the energy spectrum and the chemical content, such as U, Th, and K, using a $LaBr_3$ scintillation detector and ED-XRF. In addition, HPGe detector was used to analyze the radioac-tivity of $^{234}Th$, $^{234}mPa$, and $^{214}Bi$ in uranium decay series and $^{228}Ac$, $^{212}Pb$, and $^{208}Tl$ in thorium decay series, and $^{40}K$. The correlation between characteristic variables, such as the count rate in several ROIs, chemical content, and radioactivity, was assessed to infer the radioactivity of natural radionuclides through a rapid screening method. Based on the results, a characteristic database for raw material and by-product in domestic distribution was established and it will provide useful information in the analysis procedure and improve the accuracy and reproducibility in the analysis of natural radionuclides.

• Journal of the Korea Convergence Society
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• v.10 no.2
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• pp.285-292
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• 2019

Panax ginseng is known for various pharmacological activities mainly due to saponins. Since minor saponins, generated by the decomposition of major saponins, generally exert higher activities than major saponins, the fermentation may increase the minor saponin contents in ginseng products. In this study, we tested fermented ginseng extract whether or not provide a safe cosmetic ingredient for whitening purpose. In this regard, fermented Ginseng extract was prepared and evaluated the inhibitory activity toward tyrosinase and the melanin synthesis suppression. The safety was tested via cell viability and toxicity test. The skin lightening effect was also evaluated by clinical study. The fermented Ginseng extract exerted higher activities in tyrosine inhibition and in suppressing melanin synthesis compared to Kojic acid and arbutin. In the clinical test, skin lightening effecte of the sample was clearly higher than vehicle or Vitamin C. We thus concluded that the fermented Ginseng extract may provide a safe cosmetic ingredient for skin lightening purpose.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.189.2-190
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• 2003

현재까지 미생물의 증식을 억제하는 보존제로는 인공합성품이 많이 알려져 이들이 주로 상업적으로 사용되고 있으나 그 안정성이 경우에 따라 문제되고 있으며 근래소비자의 건강 지향적 욕구가 증대됨에 따라 인공합성품의 기피현상이 두드러지고 있다. 따라서 이들 천연 항균물질의 개발과 이용은 인공 합성보존제의 대처라는 의미와 소비자기피현상을 유발시키지 않으면서 각종 가공식품의 저장성향상 및 저온 유통식품의 안정성확보라는 견지에서 그 중요성이 있다. 본 실험에서는 식품의 미생물 작용에 의한 변질의 저해 효과가 뛰어난 식물성천연항균제품(Botanical antimicrobial agents-Citrus product : 이하 BAAC라 칭함)에 천연보조제(Ginseng extract, Aloe, 매실추출물)를 첨가하여 Paper disk 법에 의한 항균성 검사를 실시한 결과 Ginseng extract를 첨가한 경우 생육저해환이 가장 크고 뚜렷하게 나타났다. 따라서 BAAC에 보조제(Ginseng extract)를 첨가하여 제조 된 천연 항균복합제재(이하 BAAG라 칭함)를 우유에는 각 농도별로 첨가하여 4$^{\circ}C$의 냉장상태와 2$0^{\circ}C$의 상온에서 저장하였고, 계란과 콩나물의 경우는 침지 처리한 후 꺼내어 상온에서 저장하면서 각각 주사전자현미경 관찰, 대장균수, 총균수의 변화, 외관상의 변화에 미치는 영향을 무처리 대조구와 비교하면서 조사하였다. 아울러, 계란의 경우는 조단백함량의 변화도 관찰하였다. 주사전자현미경 촬영사진의 결과 분석을 통하여 BAAG를 처리한 균체 세포는 세포막 및 세포벽 기능이 파괴되어 세포내용물이 균체외부로 유출되어 균체의 생육이 억제되며 성장을 저해 또는 사멸시키는 것으로 나타났다. 대장균수는 우유, 달걀 및 콩나물의 모든 처리구에서 BAAG의 첨가에 의해 성장이 억제되었으며 농도가 증가시킬수록 균증식 억제 효과가 뚜렷하였으며, 총균수도 압도적으로 낮은 간을 보여주었다. 달걀의 조단백함량의 변화는 BAAG를 처리하지 않은 무처리 대조구에 비하여 침지 처리한 경우가 조단백 변화가 크지 않았다. 즉, BAAG의 침지 처리한 경우, 저장기간 14일이 경과 한 후에 10%정도의 수준으로 감소한데 반하여, 무처리구인 대조구의 경우, 23%수준으로 감소 증도가 증가하였다. 외관상의 변화와 상품 가치를 측정한 결과는 달걀의 경우, 14일이 경과후에는 무처리 대조구에서 흰자위의 감소와 노른자위와의 경계가 뚜렷하지 못하여 상품으로서의 가치가 크게 떨어진 상태였다. 우유의 경우에는 4$^{\circ}C$와 2$0^{\circ}C$에 저장된 대조구에서는 각각 3일과 12일경과 후 강한 부패취와 아울러, 표피의 갈변정도가 심하되어 관능적으로 부패상태를 인지할 수 있었다. 콩나물의 경우도 저장3일 경과 후에 부패취와 함께 점질성 갈변물질이 생성되었다. 이와 같은 결과로 볼 때, BAAG의 처리는 BAAC의 경우보다 가격은 저렴하면서도 항균력은 우수한 천연 항균복합제재로써 농산물 식품원료에 적용하여 선도유지 기간을 연장할 수 있는 효과를 기대할 수 있었다.

• Journal of the Korean Applied Science and Technology
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• v.37 no.6
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• pp.1583-1590
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• 2020

In this study, activity of anti-oxidation of Cinnamomum loureiroi extract (CLE). In order to measure anti-oxidation effect of CLE, phenol content of CLE, radical scavenging activity of ABTS and DPPH, and decrease of ROS production. Before the experiment, against Raw 264.7 cell, a cytotoxicity was measured and the result showed no toxicity. CLE's total polyphenol amount was 397.7±8.3 mg/g and the total flavonoid amount was 101.899±0.885 mg/g. As a measurement result of ABTS radical scavenging ability and DPPH radical scavenging ability, radical scavenging ability increased depends on the concentration. CLE's effect on the ROS creation was checked and the result showed that CLE suppressed ROS creation by showing a meaningful decrease of ROS generation. From all of the results, CLE is know to have an antioxidant effect. These results will be provided as fundamental data for further development of the new material of functional cosmetics to the results above.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.284-291
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• 2018

In this study, a dust inhibitor for road dust was prepared by using molecular structure, molecular weight, viscosity, hydrophilicity, swelling, wetting and moisturizing properties of natural polysaccharide which is widely used as food and cosmetic materials. Various dust control effects were confirmed and superior results were obtained than simple water spraying and synthetic for control(PVA). In addition, the comparison of water evaporation, scattering inhibition rate, Field test, and determining acute lethality of effluents to Daphnia magna were studied and the safety of soil and water quality was studied. The availability of the dust inhibitor was confirmed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1351-1357
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• 2016

Green tea (Camellia sinensis) seed extract (GTSE) was prepared under various pretreatment conditions and used to investigate its extraction yield and anti-yeast activity. Anti-yeast activity of GTSE from seeds with or without the coats was the same, whereas the extraction yield was slightly higher in extract from seeds without the coat. Anti-yeast activity of GTSE from seeds with different water contents or particle sizes was the same, whereas the extraction yield was highest in extract from seeds with 7.3% moisture or a smaller particle size. Anti-yeast activity of defatted green tea seed extract (DGTSE) was the same as that of GTSE. Extraction yield was higher in DGTSE from defatted seeds by the oil press machine compared to hexane extraction. Defatted green tea seed (DGTS), a by-product from the oil extraction process, is a good natural source of anti-yeast preservative. The extraction yield and anti-yeast activity of DGTSE were investigated using various extraction solvents, temperatures, and times. The results show that water was an economic extraction solvent, and anti-yeast activity of DGTSE was unstable at $90^{\circ}C$. These results suggest that water, extraction temperature of $50^{\circ}C$, and extraction time of 4 h were the most efficient for extraction of anti-yeast compounds from DGTS.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.325-329
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• 2016

Extracting natural dyes have been widely studied since the needs of eco-friendly and non-toxic natural dyes increased. In this paper, the natural dyes were extracted from sappan wood, gardenia, and mugwort containing brazilein, crocin, and chlorophyll process. After the extraction with variables of pH of solvent and reaction time, the chromaticity of extracted natural dyes was analyzed using quantitative values from brightness and color coordinate (L, a, b) based on the target colors of red, yellow and green. For the case of brazilein and crocin, the cadmium red and cadmium yellow, respectively were extracted. In the case of sappan wood and gardenia, the red pigment under pH 12 (${\Delta}$ = 18.2) and the yellow pigment at pH 9 (${\Delta}$ = 18.4) were extracted respectively. However, the color of extracted chlorophyll from mugwort was different from the target chrome green.

• Journal of the Korean Institute of Gas
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• v.25 no.1
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• pp.30-39
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• 2021

Natural gas is globally emerging as an important energy source for environmental, political and regional reasons. In Korea, natural gas imported from oversea natural gas resources as a LNG, it is increased for an applications as a fuel and feedstock which replace the coal and nuclear energy. Because it is relied on the import market in Korea, it is very important to analyze the security for supply. Therefore, this study suggested a method for reducing supply risk and for providing stable supply and demand through risk analysis of Korea's import structure. In order to reduce the supply risk, the concentration of importing countries should be lowered and it is necessary to lower the proportion of countries with relatively low GSSI and increase the imports from Russia. Finally increasing the number of importing countries or maintaining friendly relations with countries where the supply is stable could give us the positive impact in terms of total GSSI.

• Journal of the KSME
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• v.34 no.5
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• pp.326-333
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• 1994

신소재의 보편적인 정의는 "재료의 원료를 새로 개발하거나, 종래의 원료에 개선된 제조기술 또는 응용기술을 적용시켜 종래에 없던 우수한 특성, 기능을 갖게 하는 소재"라고 한다. 즉, 고 부가 가치의 금속, 세라믹스, 폴리머, 복합재료를 총칭하여 신소재 또는 첨단소재(advanced materials) 라고 하며, 산업기기의 중요한 기능소재로서 기계공업의 발전에 필수적이다. 1970년대부터 1980 년대 초반에 걸쳐 본격적으로 시작된 세라믹스에 관한 연구는 제조 및 사용분야 전반에 걸쳐 기술혁신을 가져왔다. 그후 천연 광석분말만이 아니라 새로운 화학적 방법으로 제조된 분말을 사용하여 창출된 재료라는 뜻으로 "뉴(new)세라믹스"라고 불려지거나, 개선된 제조기술을 통하여 재료의 섬세한 미세조직을 얻음으로 우수한 특성을 갖는 재료라는 뜻으로 "파인(fine)세라믹스" 등의 이름이 붙여지게 되었다. 이제 센서용 소재는 물론이고, 가위, 손목시계 케이스, 바이오 세라믹스 등에 이르기까지 10년 전보다 훨씬 다양하게 세라믹스를 사용한 물체를 발견할 수 있다. 이들 세라믹스 중 기계적, 또는 열 응력을 받는 구조물에 적용되는 것을 구조 세라믹 스(structural ceramics)라고 한다. 이 글에서는 차세대 자동차 및 항공기에까지 적용이 시도되고 있는 이들 구조세라믹스를 대상으로 하여 일반적으로 제조법, 응용분야, 연구동향 및 전망을 정리하고자 한다.조법, 응용분야, 연구동향 및 전망을 정리하고자 한다.