• 한국잡초학회지
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• 제17권4호
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• pp.375-381
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• 1997

볏단이 있던 곳이나 콤바인 수확한 볏짚이 피복된 곳은 잡초 발생인 생육이 감소하는 현상이 관찰되고 있다. 이는 볏짚에 함유한 allelopathic 물질에 의한 것으로 추정되어 볏짚을 80% 메칠알콜로 추출후 둑새풀로 생물검정, 10종의 표준 유기산이 둑새풀의 생육과 발아에 미치는 영향, 볏짚추출물을 silicagel column 으로 분획후 HPLC, GC/MS로 분석한 결과는 아래와 같았다. 1. HPLC분석에 의하여 볏짚에는 fumaric acid와 4종류의 미확인 유기산이 확인되었다. 2. fumaric acid를 포함한 7종의 유기산은 $10^{-2}$의 농도에서 둑새풀의 생육을 상당히 억제하였고 특히 발아를 100-90% 억제시켰다. 3. 볏짚에 함유한 물질중 억제효과가 가장 큰 것은 GC/MS분석에 의하여 II-4-4Rf 0.5에 함유한 물질로 분자량 253인 치환된 유기산인 신물질로 Octadecanoic acid, 2-oxo-, methyl ester에서 methyl ester가 유리된 물질로 추정되었다.

• Journal of the Korean Wood Science and Technology
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• 제48권6호
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• pp.769-779
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• 2020

This study investigates the selective fractionation of lignin with uniform structures and lower molecular weight. Lignin solubilization was first performed using a solution of acetic acid (AA) and hydrogen peroxide (HP) (4:1, (v/v)) to form peracetic acid (PAA), which is a strong oxidant. After the PAA-induced solubilization that occurred at 80℃, totally soluble lignin was extracted by ethyl acetate (EA) and divided into organic- and water-soluble fractions. The EA fraction was then fractionated by open-column using three solutions (chloroform-ethyl acetate, methanol, and water) sequentially. With an increase in the solvent polarity during the fractionation step, the molecular weight of the lignin-derived compounds in the fraction increased. Remarkably, some lignin fractions did not have aromatic structures. These fractions were identified as carboxylic acid-containing polymers like poly-carboxylates. These results conclude that the selective production of lignin-derived polymers with specific molecular weight and structural characteristics could be possible through open-column fractionation.

• Journal of Ginseng Research
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• 제1권1호
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• pp.25-28
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• 1976

몇 가지 유기용매를 사용하여 인삼 추출액을 분별 분리하여 몇 개의 분칠들을 얻어서 이들이 RNA중합효소의 활동성에 미치는 영향을 조사하였다. 백삼과 홍삼에서 모두 RNA 중합효소의 활동성에 양성적인 효과를 가진 분획들을 얻었다. 백삼의 경우 RNA 중합효소에 양성적인 효과를 미치는 성분들은 전체 메탄을 추출액 분획, 초산에틸 추 출모액 및 이 모액의 수용성 분획들에서 확인되었고 흥삼의 경우에는 전체 메탄을 추출액 분획과 에테르 분획들에서 확인되었다. 이 사실은 중합효소에 양성적인 효과를 나타내는 성분들이 무극성 및 극성 부분들로 이루어져 있으며, 그들이 홍삼의 가공과 정에서 두 부분으로 분해되었을 것이라는 것을 암시의 준다.

• Natural Product Sciences
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• 제11권3호
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• pp.127-130
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• 2005

This study was carried out to investigate inhibitory effect of extracts from root cortex of Paeonia suffruticosa on ${\alpha}-glucosidase$ (EC 3. 2. 1. 20) and postprandial hyperglycemia. Methanol extract and organic solvent (n-hexane, ethyl acetate, butanol, aqueous) fractions from the crude drug were determined for the inhibitory activities against maltase, sucrase and ${\alpha}-amylase$. The methanol extract from the crude drug strongly inhibited maltase (72%) and sucrase (76%) at the concentration of $100\;{\mu}g/ml$. Among the fractions examined, the ethyl acetate fraction from the natural plant drug showed potent inhibitory effects on maltase (85%) and sucrase (81%) at the concentration of $100\;{\mu}g/ml$. The ethyl acetate fraction from root cortex of Paeonia suffruticosa also exhibited significant reductions (21%) of blood glucose elevation in mice loaded with maltose.

• Natural Product Sciences
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• 제10권5호
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• pp.223-227
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• 2004

This study was carried out to investigate inhibitory effect of extracts from the root of Paeonia lactiflora on postprandial hyperglycemia. Organic solvent (hexane, ethyl acetate, butanol, aqueous) extracts from the crude drug were fractionated by high performance liquid chromatography. These fractions were examined to evaluate ${\alpha}-glucosidase$ (EC 3. 2. 1. 20) inhibition by microplate colorimetric assay. Among the fractions examined, the ethyl acetate fraction from the roots of Paeonia lactiflora showed potent inhibitory effects on ${\alpha}-glucosidase$. Therefore, further fractionation of the fraction was carried out to isolate the active principles. Finally, we isolated and Purified 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG) as a active principle by activity-guided fractionation. These results suggest that the extract from the root of Paeonia lactiflora can be used as a new nutraceutial for inhibition on postprandial hyperglycemia and PGG might be a candidate for developing an ${\alpha}-glucosidase$ inhibitor.

• The Korean Journal of Ecology
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• 제10권3호
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• pp.139-149
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• 1987

Mathematical models of the litter accumulation, decay and turnover in the grassland and forest ecosystems of equilibrium state of the annual litter production were established to analyse the decay rates of organic and inorganic constituents of the litter. Those models were validated by an application to a Phragmites longivalvis grassland in a delta of the River Nakdong. The decay constants of cold-water-soluble fractions, other carbohydrates, hot-water-soluble fractions, cellulose, crude fat, lignin and crude protein in the litter were 0.730, 0.583, 0.555, 0.505, 0.479, 0.331 and 0.310 respectively. The amount of mineral nutrients such as N. P. K. Ca and Mg returned annually to the soil were estimated to 7.09, 1.34, 2.36, 4.37 and 0.79g/m2 respectively.

• 한국식품영양과학회지
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• 제30권2호
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• pp.338-343
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• 2001

The ethanol extract of Quercus mongolica leaf was fractionated by various organic solvents, and their antimicrobial and antioxidative activities were investigated against several microorganisms. The ethanol extract of Quercus mongolica leaf at two thousand $\mu\textrm{g}$ per disc showed 17~21mm inhibition zone against Gram postive and Gram negative bacteria. Among the various solvent fractions from ethanol extract of Quercus mongolica leaf, the hexane fraction showed the strongest antimicrobial activity. Minimal inhibitory concentration (MIC) of hexane fraction was 250$\mu\textrm{g}$/mL against Bacillus cereus, 250~500$\mu\textrm{g}$/mL against Listeria monocytogenes, 500$\mu\textrm{g}$/mL against Staphylococcus aureus, Salmonella typhimurium, Escherichia coli O157, and Pseudomonas aeruginosa. Also, the hexane and chloroform fraction had the similar antioxidative activity compared to that of butylated hydroxy toluene(BHT).

• 한국환경농학회지
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• 제35권2호
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• pp.128-136
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• 2016

BACKGROUND: Hydrothermal carbonization reaction is the thermo-chemical energy conversion technology for producing the solid fuel of high carbon density from organic wastes. The hydrothermal carbonization reaction is accompanied by the thermal hydrolysis reaction which converse particulate organic matters to soluble forms (hydro-thermal hydrolysate). Recently, hydrothermal carbonization is adopted as a pre-treatment technology to improve anaerobic digestion efficiency. This research was carried out to assess the effects of hydro-thermal reaction temperature on the methane potential and anaerobic biodegradability in the thermal hydrolysate of organic sludge generating from the wastewater treatment plant of poultry slaughterhouse .METHODS AND RESULTS: Wastewater treatment sludge cake of poultry slaughterhouse was treated in the different hydro-thermal reaction temperature of 170, 180, 190, 200, and 220℃. Theoretical and experimental methane potential for each hydro-thermal hydrolysate were measured. Then, the organic substance fractions of hydro-thermal hydrolysate were characterized by the optimization of the parallel first order kinetics model. The increase of hydro-thermal reaction temperature from 170℃ to 220℃ caused the enhancement of hydrolysis efficiency. And the methane potential showed the maximum value of 0.381 Nm³ kg^-1-VS_added in the hydro-thermal reaction temperature of 190℃. Biodegradable volatile solid(VSB) content have accounted for 66.41% in 170℃, 72.70% in 180℃, 79.78% in 190℃, 67.05% in 200℃, and 70.31% in 220℃, respectively. The persistent VS content increased with hydro-thermal reaction temperature, which occupied 0.18% for 170℃, 2.96% for 180℃, 6.32% for 190℃, 17.52% for 200℃, and 20.55% for 220℃.CONCLUSION: Biodegradable volatile solid showed the highest amount in the hydro-thermal reaction temperature of 190℃, and then, the optimum hydro-thermal reaction temperature for organic sludge was assessed as 190℃ in the aspect of the methane production. The rise of hydro-thermal reaction temperature caused increase of persistent organic matter content.

• 한국토양비료학회지
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• 제40권4호
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• pp.326-329
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• 2007

Quantifying soil organic carbon (SOC) has long been considered to improve our understanding of soil productivity, soil carbon dynamics, and soil quality. And also SOC could contribute as a major soil management factor for prescribing fertilizers and controlling of soil erosion and runoff. Reducing tillage intensity has been recommended to sequester SOC into soil. On the other hand, determination of traditional SOC could barely identify the tillage practices effect. Physical soil fractionation has been reported to improve interpretation of soil tillage practices impact on SOC dynamics. However, most of these researches were focused onupland soils and few researches were conducted on paddy soils. Therefore, the objective of this research was to evaluate paddy soil tillage impact on SOC by physical soil fractionation. Soils were sampled in conventional-tillage (CT), partial-tillage (PT), no-tillage (NT), and shallow-tillage (ST)plots at the National Institute of Crop Science research farm. Samples were obtained at the three sampling depth with 7.5-cm increment from the surface and were sieved with 0.25- and 0.053-mm screen. Soil organic carbon was determined by wet combustion method. Significant difference of SOC contentwas found among sampling soil depth and soil particle size. SOC content tended to increase at the ST plot with increasing size of soil particle fraction. We conclude that quantifying soil organic carbon by physical soil particle fractionation could improve understanding of SOC dynamics by soil tillage practices.

• 한국미생물·생명공학회지
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• 제39권2호
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• pp.168-174
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• 2011

본 연구에서는 안전하고 효율적인 항진균제 개발 연구의 일환으로 73종의 약용 및 식용식물의 메탄올 추출물을 조제하고 이들의 hexane, methylene chloride, ethylacetate, butanol 분획물 및 water 잔류물 365종을 각각 조제하여 Aspergillus niger에 대한 항진균력을 조사하였다. 활성 선별단계에서 비교적 경제적이면서도 손 쉬운 순차적 유기용매 분획물을 제조하여 항진균 천연물 탐색을 시도함으로서 기존에 천연물 추출물에서 검색되지 않은 참나물, 뽕나무, 단삼의 항진균 활성을 확인하였다. 특히 항진균 활성이 보고된 바 없는 참나물의 경우 methylene chloride 분획에서 A. niger에 대한 MIC, MFC 가 각각 0.25 및 0.5 mg/mL임을 확인하여 강력한 항진균 활성을 확인하였으며, 0.25 mg/mL 농도에서 포자발아 억제활성도 나타냄을 확인하였다. 또한 활성분획은 0.5 mg/mL농도까지 인간 적혈구에 대해 용혈활성을 나타내지 않았으며, 활성물질은 당이 결합된 flavonoid로 추측되었다. 본 연구결과는 참나물 methylene chloride 분획의 우수한 항진균 활성을 제시하며, 비교적 간단한 유기 용매 분획법을 이용한 천연물 시료제조 및 이를 이용한 활성탐색이 새로운 활성물질 선별에 효과적임을 제시하고 있다.