• 한국수산과학회지
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• 제12권4호
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• pp.225-234
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• 1979

자원이 풍부한 해조류 단백질의 효율적인 이용과 이의 영양가를 구명하기 위하여 가장 효과적인 정제방법 및 추출용매를 결정하고 4종 식용해조 즉 둥근 돌김, 구멍갈파래, 미역 및 모자반의 추출 정제단백질의 아미노산 조성과 이의 영양가 및 소화율을 실험한 결과를 요약하면 다음과 같다. 1. 홍조류와 녹조류는 추출단백질을 TCA로 심전시킨 후 ethylether로 TCA를 충분히 제거하면 정제효과가 좋았고, 갈조류는 등전점을 이용한 정제방법의 효과가 좋았다. 2. 각종 용매로 추출한 단백질의 아미노산을 분석한 결과 홍조류와 녹조류는 물 또는 알칼리 추출한 단백질이 좋았고, 갈조류는 알코올-알칼리 혼합용매로 추출한 단백질이 좋았고, 3. 둥근돌김의 정제단백질은 lyeine의 함량이 전시료 중에서 가장 높았으며 구멍갈파래는 threonine의 함량이 월등히 높은 반면, lysine의 함량이 낮았으며 미역과 모자반의 아미노산 분포 양상은 둥근돌김과 구멍갈파래보다 좋지 못했다. 4. 둥근돌김과 구멍갈파래 원조분말의 chemical score는 35정도였으나 정제단백질은 56정도있고, 미역과 모자반은 원조분말이 $10\~16$정도로 극히 낮은 반면에 정제단백질은 $30\~35$ 정도를 나타내었고, protein score는 전시료가 정제단백질의 경우 $62\~73$ 정도를 나타내었다. 5. PPDRI를 이용한 소화율은 원조분말의 $25\~40$ 정도의 낮은 소화율을 보였으나 정제했을 경우에는 $1.3\~2.1$배 증가함을 보였고, 갈조류의 소화율은 일반적으로 극히 낮음을 알 수 있었다.

• 한국식품영양학회지
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• 제13권4호
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• pp.319-327
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• 2000

배추김치에 0.25% chitosan, 0.5% chitosan, 0.5% chitosan+0.04M Na-malate, 0.5% chitosan+0.04M Na-lactate, 0.5% chitosan+04M Na-citrate를 첨가하여 김치의 숙성 과정 중 pH, 산도, pH/TA ratio, ascorbic acid 함량 및 Pectin질의 변화에 대한 영향을 알아보았다. 그 결과는 다음과 같다. 1. 김치의 숙성과정 중 pH는 감소하는 경향을 보였으며, 대조군, 0.25% chitosan 첨가군, 0.5% chitosan 첨가군, 0.5% chitosan+Na-citrate 첨가군, 0.5% chitosan+Na-malate 첨가군, 0.5% chitosan+Na-lactate 첨가군의 순으로 감소하였다. 2. 김치의 숙성과정 중 산도는 증가하는 경향을 보였으며, 대조군, 0.5% chitosan+Na-malate 첨가군, 0.25% chitosan 첨가군, 0.5% chitosan+ Na-citrate 첨가군. 0.5% chitosan 첨가군, 0.5% chitosan+Na-lactate 첨가군의 순으로 증가하였다. pH/TA ratio는 김치의 숙성 중 감소하는 경향을 보였으며. 대조군, 0.25% chitosan 첨가군, 0.5% chitosan+Na-malate 첨가군, 0.5% chito-san+Na-citrate 첨가군, 0.5% chitosan+Na-lactate 첨가군의 순으로 감소하였다. 3. Ascorbic acid 함량은 3일째에 가장 높은 함량을 보였으며, 0.5% chitosan에 유기산염 병용첨가군이 다른 군들보다 월등히 높았다. 그 후 숙성기간이 경과할수록 감소하였다. 4. AIS 함량의 변화는 숙성기간이 지날수록 모두 감소하는 경향을 보였으며, 대조군, 0.25% chit-osan 첨가군, 0.5% chitosan 첨가군, 0.5% chito-san+Na-citrate 첨가군, 0.5% chitosan+Na-lactate 첨가군, 0.5% chitosan+Na-citrate 첨가군 순으로 감소하였다. 5. AIS로부터 펙틴을 추출하여 HWSP, HXSP, HCISP로 분획한 함량비는 대조군이 숙성이 진행됨에 따라 HWSP가 증가하고 HCISP는 감소하는 경향을 보인 반면, chitosan 첨가군은 숙성이 진행됨에 따라 HWSP가 감소하고 HCISP는 증가하는 경향을 나타내었다. 위와 같은 결과로부터 chitosan의 첨가는 김치의 보존성 향상에 효과를 보였으며. 유기산염과 병용첨가군이 단독첨가군보다 더욱 효과적이었다. 유기산염의 종류에 따른 병용에 있어서는 Na-lactate 첨가군이 Na-citrate와 Na-malate 첨가군보다 효과적으로 나타났다.

• 농업과학연구
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• 제43권4호
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• pp.522-536
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• 2016

Fluorine is unique chemical element which occurs naturally, but is not an essential nutrient for plants. Fluoride toxicity can arise due to excessive fluoride intake from a variety of natural or manmade sources. Fluoride is phytotoxic to most plants. Plants which are sensitive for fluorine exposure even low concentrations of fluorine can cause leave damage and a decline in growth. All vegetation contains some fluoride absorbed from soil and water. The highest levels of F in field-grown vegetables are found up to $40mg\;kg^{-1}$ fresh weight although fluoride is relatively immobile and is not easily leached in soil because most of the fluoride was not readily soluble or exchangeable. Also, high concentrations of fluoride primarily associated with the soil colloid or clay fraction can increase fluoride levels in soil solution, increasing uptake via the plant root. In soils more than 90 percent of the natural fluoride ranging from 20 to $1,000{\mu}g\;g^{-1}$ is insoluble, or tightly bound to soil particles. The excess accumulation of fluorides in vegetation leads to visible leaf injury, damage to fruits, changes in the yield. The amount of fluoride taken up by plants depending on the type of plant, the nature of the soil, and the amount and form of fluoride in the soil should be controlled. Conclusively, fluoride is possible and long-term pollution effects on plant growth through accumulation of the fluoride retained in the soil.

• 한국대기환경학회지
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• 제13권6호
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• pp.487-495
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• 1997

The most desirable diesel oxidation catalyst (DOC) should have the properties of oxidizing CO, HC and SOF effectively at low exhaust gas temperature while minimizing the formation of sulfate at high exhaust gas temperature. Precious metals such as platinum and palladium have been known to be sufficiently active for oxidizing SOF and also to have high activity for the oxidation of sulfur dioxide $(SO_2)$ to sulfur trioxide $(SO_3)$. There is a need to develop a highly selective catalyst which can promote the oxidation SOF efficiently, on the other hand, suppress the oxidation of $SO_2$. In this study, a Pt-V catalyst was prepared by impregnating platinum and vanadium onto a Ti-Si wash coated ceramic monolith substrate. A prepared Pt-V catalytic converter was installed on a heavy duty diesel engine and the effect of fuel sulfur on particulate matter (PM) of heavy duty diesel engine was measured. The effect of fuel sulfur on PM of Pt-V was also compared with that of a commercialized Pt catalyst currently being used in some of the heavy duty diesel engines in advanced countries. Only 1 $\sim$ 3% of sulfur in the diesel fuel was converted to sulfate in PM for the engine without catalyst, but almost 100% of sulfur conversion was achieved for the engine with Pt catalyst at maximum loading condition. In the case of Pt-V catalyst, there was no big difference in conversion with the base engine even at maximum loading condition. The reason of SOF increase according to the increase of suflate emission was identified as the washing off effect of bound water in sulfate.

• Asian-Australasian Journal of Animal Sciences
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• 제20권7호
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• pp.1127-1134
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• 2007

Gels were made from surimi-like pork (SLP) made from muscles obtained at 1, 24 and 72 h post-mortem. The SLP from pre-rigor muscle had higher pH and moisture percentage compared to in- or post-rigor muscles. Also, SLP from pre-rigor muscle showed higher concentration of water-soluble protein that was washed out during the process. Gel from post-rigor muscle exhibited higher a* and b* value, and also resulted in higher Chroma and lower hue values. The dark color of gel from post-rigor muscle was related to higher concentration of sarcoplasmic protein in SLP and denser structure in the gel matrix. SDS-PAGE showed higher intensity of the phosphorylase in the sarcoplasmic protein fraction from pre-rigor muscle. Gel from post-rigor muscle showed higher hardness and sensory firmness, and the greater firmness was related to higher concentration of protein in SLP, and a compact network with smaller pockets in the gel matrix.

• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.809-814
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• 2003

${\beta}-amyloid$ ($A{\beta}$) peptides from the proteolytic processing of ${\beta}-amyloid$ precursor protein (${\beta}-APP$) aggregates in the brain to form senile plaques, and their aggregation plays a key role in pathogenesis of Alzheimer's disease (AD). To isolate an active compound that has an $A{\beta}$ aggregation-inhibitory activity, 2,000 microbial metabolite libraries were screened based on their ability to inhibit $A{\beta}$ aggregation by using both Congo red and thioflavin T assays. As a result, a water-soluble fraction of a soil microorganism, KK565, showed a potent $A{\beta}$ aggregation-inhibitory activity. The strain was identified as Streptomyces species, based on the cultural and morphological characteristics, the presence of diaminopimelic acid in the cell wall, and the sugar patterns for the whole-cell extract. In addition, the purification of active principle resulted in identifying a heat-unstable protein responsible for the $A{\beta}$ aggregation-inhibitory activity.

• Journal of Forest and Environmental Science
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• 제18권1호
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• pp.53-60
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• 2001

편백나무 잎을 채취하여 건조시킨 후 분말로 제조하여 아세톤-물(7:3, v/v)로 추출하고 헥산, 메틸렌클로라이드, 에틸아세테이트, 그리고 수용성으로 분획하여 동결건조 시켰다. 그 중에서 에틸아세테이용성 분획을 Sephadex LH-20으로 충진한 칼럼에서 메탄올과 에탄올-헥산 혼합액을 용매로 사용하여 칼럼크로마토그래피를 실시하였다. 단리된 화합물들은 박층크로마토그래피(TLC)로 확인한 후 NMR스펙트럼을 사용하여 정확한 구조규명을 하였고 FAB-MS스펙트럼으로 분자량을 측정하였다. 주로 많은 양의 taxifolin-3-O-${\beta}$-D-xylopyranoside와 (+)-catechin이 포함되어 있었으며 소량의 quercetin-3-O-${\alpha}$-L-rhamnopyranoside도 함께 단리 되었다.

• 미생물학회지
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• 제16권4호
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• pp.170-179
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• 1978

By the successive enrichment culture, more than 250 methanol-utilizing bacteria were isolated from various samples such as soil, waste water and sewage. Two strains of which were selected and tentatively identified as Acinetobacter sp. and Pseudomonas sp. experiments were carried out to determine the growth conditions for the higher biomass yield and to demonstrate the difference to protein composition dependent upon carbon sources of these two species. the results were as follows ; 1. the optimum pH was determined as 8 in the both species. The optimum temperature in Acinetobacter sp. was $25^{\circ}C{\sim}30^{\circ}C$ and pseudomonas sp. was $30^{\circ}C-35^{\circ}C$. The optimum initial concentration of mthanol was determined as 1-2% in Acinetobacter sp. and 2-3% in pseudomonas sp. 2. The optimum concnetrations of nitrogen source, micro-elements, and vitamins such as biotin and thiamine-HCl in Acnetobactar sp. were 1g $(NH_4)_3SO4,\;1{\sim}3mg\;Mn^{++},\;4mg\;Fe^{++},\;10{\mu}g\;biotin,\;and\;100{\mu}g$ thiamine-HCl per liter medium. In the Pseudomonas sp., 2g $(NH_4)_3SO4,\;1mg\;Mn^{++},\;trace\;amounts\;of\;Fe^{++},\;5{\mu}g\;biotin,\;and\;100{\mu}g$ thiamine HCl per liter were effective. Maximum biomass yield was 2.5g/l in Acinetobacter sp. and 4.8g/l in Pseudomonas sp. 3. Protein composition of the two strains exhibited that alkai-labile protein was higher than alkali-stable protein. In Pseudomonas sp., the contents of acid soluble fraction and alkali-stable protein of the cells grown in the methanol medium were higher than in sucrose medium. On the other hand, in Acinetobacter sp., alkalilabile protein of the cells grown in sucrose medium was higher than in methanol medium.

• 자원환경지질
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• 제29권1호
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• pp.87-103
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• 1996

The purposes of this research are to investigate the pollution level of heavy metals due to the urbanization and industrialization in the satellite cities of Seoul, and to assess the chemical species and the sources of heavy metals in highly contaminated soils and dusts. Soil and dust samples were collected from the Uijeongbu and the Koyang cities, which are northern and the northwestern satellite cities of Seoul metropolitan city, respectively. Relatively high pH values($6.3{\sim}9.9$) were found in roadside soils compared with agricultural and forest soils. Difference in pH values of soils was not identified between before and after rainy seasons. In spite of no specific pollution sources in the above cities, the contents of Cu, Pb, and Zn in soils and dusts were much higher than the world average contents. The metal levels in dusts were higher than those in soils, but the metal concentration in dusts was significantly decreased after rainy season. Pollution index was high(> 1.0) in the areas of heavy traffic, industrial complex, and city centres. There is an appreciable proportion of total Zn in exchangeable/water-acid soluble fraction. Copper is predominantly associated with reducible and oxidizable phases, whereas Pb is largely in reducible association. It is concluded that the mobility and bioavailability of metals are high in the order of Zn >> Cu > Pb, on the basis of characteristic particle morphology and chemical composition, Pb-containing particles are originated probably from the automobile exhaust, particularly in heavy traffic areas. The metallic forms and iron-oxide associated forms of Cr, Ni, Cu, Zn, and Pb can be assessed as industrial origin.

• Food Science and Biotechnology
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• 제14권1호
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• pp.58-63
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• 2005

Ethyl acetate-soluble neutral fraction of hot water extracts from the aerial parts of Angelica keiskei showed a 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. Six antioxidative compounds were purified and isolated by various chromatographic procedures. Based on the analyses of FAB-MS and NMR, the isolated compounds were structurally elucidated as luteolin 7-O-${\beta}$-D-glucopyranoside (1), quercetin 3-O-${\beta}$-D-galactopyranoside (2), quercetin 3-O-${\beta}$-D-glucopyranoside (3), quercetin 3-O-${\alpha}$-D-arabinopyranoside (4), kaempferol 3-O-${\alpha}$-D-arabinopyranoside (5), and luteolin 7-O-rutinoside (6). The glycosides of flavonols and luteolin showed DPPH radical-scavenging activity. One molecule of 2, 3, 4, 6, 1, and 5 scavenged 4.2, 4.2, 4.1, 2.5, 2.2, and 1.4 molecules of DPPH radical, respectively.