• 산업기술연구
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• 제31권B호
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• pp.127-132
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• 2011

Humic substances is accounted for for the largest proportion in natural organic matter(NOM) and NOM is widely distributed in varying concentration in all aquatic and soil. They can affect water quality adversely in several ways by contributing undesirable color, complexing with metal and yielding metal concentrations exceeding normal solubility. Ozonation is one of the efficient treatments for degradation of humic substances which cause some problems in water treatment. Especially, the combination of ozone and granular activated carbon was applied to degradation humic acid in aquatic system. The aim of this work to test the available of acid-treated granular activated carbon as catalyst in the ozonation of humic acid.

• Journal of Dairy Science and Biotechnology
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• 제31권2호
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• pp.195-200
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• 2013

The ripening of cheese allows for the development of characteristic taste and flavour, nutritional substances, bio-active components and texture, helping to improve quality. Many different microbiological, biochemical and nutritional changes occur during the process depending on the quality of raw milk, added cultures and enzymes, as well as specific processing and ripening conditions. During the ripening lactose is hydrolyzed to lactic, propionic and acetic acid, helping to reduce potential effects of the problem of lactose intolerance. Fat is hydrolyzed to butyric, propionic and conjugated linoleic acid, which function as bio-active substances. Protein is hydrolyzed to different peptides and amino acids which all show various bio-activities. However, errors of cheese ripening can happen and affect the quality of the product. To guarantee good quality cheese the process needs to be managed carefully with the right microbes used and ensuring cleanliness of processing facilities, staff, ventilation and hazard analysis and critical control points (HACCP). Research into and controlling of ripening technology is crucial for producing high quality cheeses.

• 한국식품영양학회지
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• 제8권2호
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• pp.135-144
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• 1995

Lipid oxidation in foods produce the peroxidation products, toxic substance and rancidity odor. In vivo, lipid peroxidation by free radicals or molecular singlet oxygen cause such as a damage of DNA, cancer and aging. Accordingly, the development of new compound Inhibit lipid oxidation in foods and in vivo is very important. Antioxidants are generally used as a protection material of oxidation for a storage and preservation of foods. In terms of stability of foods and health for human, development of high effective antioxidants In a nature is required. In this point of view, this paper presents the research trends of a kind of natural antioxidative substances and its antioxidative activity.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 1993년도 천연항암자원의 개발에 관한 국제학술회의
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• pp.24-30
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• 1993

• Journal of the Korean Wood Science and Technology
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• 제31권6호
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• pp.73-82
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• 2003

Various forest humic substances were collected at different climate regions with different forest types, and adsorption of heavy metals such as Cu(II), Zn(II), Cd(II) and Cr(III) were characteristically conducted to obtain optimal adsorption conditions and to evaluate the removal efficiency of heavy metals by each forest humic substance. The adsorption isotherms for Cu(II), Zn(II), Cd(II) and Cr(III) conformed to Langmuir's equation. In the stirred reactor, the removal efficiencies of Cu(II), Zn(II) and Cd(II) by forest humic substances were more than 90% but that of Cr(III) was less than 60%. The adsorption capacities of heavy metals in the stirred reactor were considerably varied depending on the type of forest humic substances. Among humic substances, the one from deciduous forest at subtropical region showed the highest removal efficiency for Cu(II). There was no significant difference in removal efficiency by each heavy metal depending on reaction temperature ranged from 20 to 50oC except for Cr(III), and the adsorptions of Cu(II), Zn(II) and Cd(II) were occurred rapidly in the incipient stage within 10 min, while Cr(III) needed more reaction time to be adsorbed. The stirred and packed bed column reactors showed similar adsorption characteristics of heavy metals by humic substances, but the removal efficiency was considerably higher in the packed bed column reactor than in the stirred reactor. Therefore, in actual operation process, a continuous packed bed column reactor was more economical.

• 한국식품저장유통학회지
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• 제10권1호
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• pp.37-40
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• 2003

딸기를 항균소재에 침지 처리한 후 1% 농도로 항균성 소재를 첨가시킨 저밀도폴리에틸렌(LDPE) 필름에 의하여 딸기를 싸서 포장하고 5$^{\circ}C$에 저장하면서 미생물 성장, 부패율, 텍스쳐, 화학적 품질을 측정한 결과 대조구에 비교해서 긍정적인 결과를 얻을 수 있었다. 즉, 항균성 소재를 포함시킨 LDPE 필름은 무첨가 대조 필름에 비해 호기성 총균수, 효모/곰팡이수로 측정된 미생물의 증식을 억제하는 것으로 나타났다. 이러한 미생물 증식억제의 효과로 인하여 항균성 필름은 포장된 딸기의 부패율을 낮추어 주고, 연화를 억제하였다. 딸기의 저장 중 pH는 상승하고 적정산도는 감소하였으며 가용성 고형분은 감소하는 경향을 보였으나 포장 처리구간에는 유의하고 일관성있는 차이를 발견할 수 없었다. 대조구 LDPE에 비교해서 항균필름의 효과를 재확인 할 수 있었으며, 황련추출물 및 GFSE등과 같은 항균소재에의 침지 처리과정을 항균필름 포장 방법과 병행하여 사용함으로써 딸기의 신선도를 연장하는 효과를 극대화 할 수 있음을 확인하였다. 이상의 연구결과로 미루어, 본 연구에서 그 기능과 효과를 구명한 천연항균소재는 수확한 딸기의 항균용처리제재 및 포장 필름 소재로 선도유지효과를 기대할 수 있어, 딸기의 생산기반 보호와 농가소득에 큰 도움이 될 것으로 생각된다.

• The Plant Pathology Journal
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• 제24권3호
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• pp.322-327
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• 2008

Antifungal activities of natural substrances from Eucalyptus darlympleana, E. globules, E. gunnii and E. unigera were evaluated against postharvest pathogens of kiwifruits, Botrytis cinerea, Botryosphaeria dothidea, and Diaporthe actinidiae, to screen effective natural substances as an alternative to chemical fungicides. Methanol extract of the Eucalyptus trees showed strong antagonistic activity against the pathogenic fungi. Among them, E. unigera and E. darlympleana effectively inhibited mycelial growth of the pathogens. For chemical identification of the antifungal substances, the methanol extract of E. darlympleana leaves was successively partitioned with $CH_2Cl_2$, EtOAc, n-BuOH and $H_2O$. Among the fractions, $CH_2Cl_2$ and n-BuOH showed strong inhibitory activity of mycelial growth of the fungi. Five compounds were isolated from EtOAc and n-BuOH fractions subjected to $SiO_2$ column chromatography. Two phenolic compounds(gallic acid and 3,4-dihydroxybenzoic acid) and three flavonoid compounds(quercetin, quercetin-3-O-$\alpha$-L-rhamnoside, quercetin-3-O-$\beta$-glucoside) were identified by $^1H$-NMR and $^{13}C$-NMR spectroscopy. Among them, only gallic acid was found to be effective in mycelial growth and spore germination of B. cinerea at relatively high concentrations. The results suggest that gallic acid can be a safer and more acceptable alternative to current synthetic fungicides controlling soft rot decay of kiwifruit during postharvest storage.

• 한국식품영양과학회:학술대회논문집
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• 한국식품영양과학회 2004년도 Annual Meeting and International Symposium
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• pp.37-42
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• 2004

The relatively new concept of functional foods is supportive of sales of food products that deliver isolated 'nutrient' or 'food compound' substances, much as is done by dietary supplements. Whether such isolated substances have benefit must be investigated in each instance; such investigations can be complex. At the same time, simply prepared natural plant foods contain a myriad of substances that, in accord with the concept of food synergy, are beneficial for health. Whole grain foods are an example of such healthy fare, based on strong epidemiologic and experimental evidence. If the concept of functional foods is to be of use for the public health, it should support the consumption of healthy traditional foods as well as promoting 'novel' foods; in this sense, whole grain foods, which have great functionality, should be regarded as functional foods.

• 한국안전학회지
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• 제2권1호
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• pp.11-16
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• 1987

A study was performed on combustion rates of three kinds of combustible substances under a few different combustion conditions. To measure the combustion rates by weight method, I contrived an apparatus using a sensitive load cell. The experimental results by the combustion tests of various combustible substances shows that the combustion circumstances, eg., air supply condition and the existence of flammable oil. And it is found that the time constant T in case of oil absence is smaller than that in case of oil existence, and the time constant T in case of enforced air-entrained condition is greater that in case of natural air-entrained condition.

• 한국환경보건학회지
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• 제43권1호
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• pp.77-86
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• 2017

Objectives: The purpose of this study was to compare permeation characteristics in three skin types using oil-soluble benzoic acid and water-soluble caffeine after method condition optimization based on OECD guideline 428. Methods: A Franz diffusion cell, a reliable alternative method for skin permeation, was used. One-milliliter samples were taken and immediately replaced with fresh solution in the receptor chamber at regular time intervals (1, 2, 4, 7, 10 and 24 hr). The amount of test substances was measured by LC-MS/MS. Results: The permeation rate increased dose-dependently, and the permeation orders were $KeraSkin^{TM}$ > hairless mouse full skin > human cadaver epidermis for skin types, and benzoic acid solution > caffeine solution > benzoic acid cream > caffeine cream for type of test materials. Conclusion: According to the definitions of Marzulli, benzoic acid and caffeine would be classified as 'fast' and 'moderate' compared with the permeation of other chemical species. The setting conditions and permeation characteristics performed in this study are expected to contribute to future permeation studies.