• Bulletin of the Korean Chemical Society
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• 제19권10호
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• pp.1036-1042
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• 1998

The preconcentration and determination of trace elements in water samples were studied by a solvent sublation utilizing dithizonate complexation. After metal dithizonates were formed, trace amounts of cadmium, cobalt, copper and lead were floated and extracted into small volume of a water-immiscible organic solvent on the surface of sample solution and determined in the solvent directly by GF-AAS. Several experimental conditions as formation condition of metal-dithizonate complexes, pH of solution, amount of dithizone, stirring time, the type and amount of surfactants, N2 bubbling rate and so on were optimized for the complete formation and effective flotation of the complexes. And also four kinds of light solvents were compared each other to extract the floated complexes, effectively. After the pH was adjusted to 4.0 with 5 M HNO3, 8.0 mL of 0.05% acetone solution of dithizone was added to 1.00 L water sample. The dithizonate complexes were flotated and extracted into the upper methyl isobutylketone (MIBK) layer by the addition of 2.0 mL 0.2% ethanolic sodium lauryl sulfate solution and with the aid of small nitrogen gas bubbles. And this solvent sublation method was applied to the analysis of real water samples and good results of more than 85% recoveries were obtained in spiked samples.

• Journal of the Korean Wood Science and Technology
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• 제47권4호
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• pp.486-497
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• 2019

The non-isothermal and isothermal pyrolysis properties of H lignin and P lignin extracted from different biorefinery processes (such as supercritical water hydrolysis and fast pyrolysis) were studied using thermogravimetry analysis (TGA) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS). The lignins were characterized by ultimate/proximate analysis, FT-IR and GPC. Based on the thermogravimetry (TG) and derivative thermogravimetry (DTG) curves, the thermal decomposition stages were obtained and the pyrolysis products were analyzed at each thermal decomposition stage of non-isothermal pyrolysis. The isothermal pyrolysis of lignins was also carried out at 400, 500, and $600^{\circ}C$ to investigate the pyrolysis product distribution at each temperature. In non-isothermal pyrolysis, P lignin recovered from a fast pyrolysis process started to decompose and produced pyrolysis products at a lower temperature than H lignin recovered from a supercritical water hydrolysis process. In isothermal pyrolysis, guaiacyl and syringyl type were the major pyrolysis products at every temperature, while the amounts of p-hydroxyphenyl type and aromatic hydrocarbons increased with the pyrolysis temperature.

• 한국응용과학기술학회지
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• 제41권2호
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• pp.520-529
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• 2024

Lycium barbarum extract has a high potential to be developed as a health functional food due to the various health-promoting effects of Lycium barbarum. This study analyzed changes in nutritional and functional components depending on the extraction solvent (purified water and a mixture of purified water and alcohol) and the condition of the sample. The nutritional components (carbohydrates, protein, fat, ash), organic acids, amino acids, total phenolic compounds, and total flavonoids of the extract produced during the extraction process were analyzed. The nutritional composition and functional substances of the extracts showed some differences depending on the type of solvent and the condition of the sample. The amounts of crude protein (7.61%), crude fat (1.63%), carbohydrate (90.22%), and ash (0.54%) of dried Lycium barbarum extract using purified water as a solvent were similar to those of the powder sample extract. The highest content of citric acid was 4.31 mg/mL, similar to the case of acetic acid, when the powder sample used a mixture of purified water and alcohol as a solvent. The highest amino acid content was 357.39 mg/mL when the powder sample was mixed with purified water and alcohol as a solvent. The total amount of phenolic compounds was 686.16 g/L when the powder sample was extracted with a mixture of purified water and alcohol as a solvent. The highest total flavonoid content was 111.32 g/L when the powder sample was extracted with a mixture of purified water and alcohol as a solvent.

• 한국토양비료학회지
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• 제22권1호
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• pp.31-38
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• 1989

식물성(植物性) 유기물질(有機物質)을 부숙(腐熟)시키면서 경시적(經時的)으로 채취(採取)한 다음 부식산(腐植酸)을 추출정제(抽出精製)한 후 산가수분해(酸加水分解)한 액중(液中)에 함유(含有)하고 있는 amino 산(酸)의 변화(變化)를 알기 위해 산야초(山野草), 활엽수(闊葉樹)잎과 침엽수(針葉樹)잎 등 3가지 식물유체(植物遺體)를 가지고 실험(實驗)한 결과(結果) 모두 17종류(種類)의 amino 산(酸)이 검출(檢出)되었다. 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 부식산(腐植酸) 가수분해액중(加水分解液中)에 함유(含有)하고 있는 amino 산(酸)의 함량(含量)과 그 분포(分布)는 식물체(植物體)에 따라, 또한 부숙정도(腐熟程度)에 따라 상이(相異)하였다. 2. 전시료(全試料) 공(共)히 중성(中性) amino 산(酸)이 가장 많이 함유(含有)되어 있었고 산성(酸性) amino 산(酸) 염기성(鹽基性) amino 산(酸)의 순서였다. 3. 총(總) amino 산(酸)의 함량(含量)은 다음과 같은 순서로 많았다. 산야초(山野草)>활엽수(闊葉樹)잎>침엽수(針葉樹)잎 4. 부열화(腐熱化)가 진전(進展)됨에 따라 lysine의 함량(含量)은 증가(增加)하였다. 5. 부숙화(腐熟化)가 진전(進展)된 시료(試料)에서는 glycine과 glufamic acid의 amino 산(酸)의 공통적(共通的)으로 다량(多量) 함유(含有)하고 있었고 부숙화(腐熟化)가 되지 않은 식물유체(植物遺體)의 부식산(腐植酸)에는 alanine, glufamic acid, glycine, aspartic acid, leucine 등 5종(種)이 가장 많이 함유(含有)하고 있었다. 6. 부숙화(腐熟化)된 시료(試料)에서는 argnine이 검출(檢出)되지 않았다. 7. penylalanine과 tyrosin은 전기간(全期間)에 걸쳐 검출(檢出)되었으며, 부숙(腐熟)됨에 따라 함량(含量)이 증가(增加)하였다.

• 대한예방한의학회지
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• 제17권3호
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• pp.177-185
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• 2013

Objective : Eucommiae Cortex is bark of Eucommia ulmoides Oliver, a deciduous tree native to China. Today, teas or herbal drugs made from E. ulmoides leaves are widely consumed as a healthy food especially in Eastern Asia including Japan, China and Korea. This study was aimed to verify the extraction efficiency of bioactive compounds from Eucommiae Cortex depending on characteristics of decoction water. Method : Six types of decoction water with various origin were prepared and the contents of minerals in water were analyzed by ICP-AES and ICP-MS. The contents of extracted bioactive compounds were analyzed by HPLC and the relationship between mineral contents and extracted bioactive compounds in the decoction water were analysed by multiple factor analysis. The decoction waters could be classified in three groups by hierarchical cluster analysis. Result : Extracted amounts of compounds in Eucommiae Cortex showed a positive relationship with Na, Si, K concentration in decoction water, while a negative relationship with Ca, Mg concentration. Conclusion : The study proved that the minerals in water influenced the extraction efficiency of bioactive compounds from Eucommiae Cortex.

• 한국버섯학회지
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• 제13권4호
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• pp.319-325
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• 2015

영지버섯의 유효성분 중, 특이적으로 영지버섯에서 검출되는 저분자 성분이며, 다양한 효능을 보이는 ganoderic acid의 함량을 분석하였다. 보유중인 영지균주를 열수, 주정, 메탄올의 용매로 추출하였고, 추출용매별 ganoderic acid A, F, H의 성분이 많은 것을 선정하였다. 추출용매별로 ganoderic acid A의 함량이 많은 5균주는 다음과 같다. 우선 열수 추출물에서는 ASI 7013이 0.988 mg/g으로 가장 높았고 다음으로, ASI 7023, 7059, 7026, 7060순 이었다. 주정 추출물에서는 ASI 7037이 0.940 mg/g으로 가장 높았고, ASI 7021, 7034, 7026, 7038순 이었다. 메탄올 추출물에서는 ASI 7162가 0.833 mg/g으로 가장 높았고, ASI 7091, 7032, 7056, 7125순 이었다. 다음으로 ganoderic acid F의 함량이 많은 5균주는 다음과 같다. 열수 추출물에서는 ASI 7101이 0.722 mg/g으로 가장 높았고, ASI 7113, 7011, 7104순 이었다. 주정 추출물에서는 ASI 7037이 0.811 mg/g으로 가장 높았고, ASI 7007, 7027, 7012, 7014순 이었다. 메탄올 추출물에서는 ASI 7154가 0.657 mg/g으로 가장 높았고, ASI 7151, 7155, 7137, 7139순이었다. 마지막으로 ganoderic acid H의 함량이 많은 5균주는 다음과 같다. 열수 추출물에서는 ASI 7013이 0.985 mg/g으로 가장 높았고, ASI 7059, 7135, 7001, 7141순이었다. 주정 추출물에서는 ASI 7106이 2.842 mg/g으로 가장 높았고, ASI 7089, 7159, 7007, 7002순 이었다. 메탄올 추출물에서는 ASI 7003이 6.969 mg/g으로 가장 높았고, ASI 7034, 7169, 7159, 7103순 이었다. 이렇게 추출용매별로 ganoderic acid 함량의 차이는 추출용매의 극성에 따른 용해도의 차이로 생각되어지며, 향후 더 깊은 연구가 필요할 것으로 사료된다.

• 대한약침학회지
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• 제15권4호
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• pp.52-65
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• 2012

Objectives: Toad venom, called Chan-Su, is a traditional Oriental medicine secreted from the auricular and the skin glands of the Bufo bufo gargarizanz Cantor or B. melanosticus Schneider and has been widely used in China, Korea and other parts of Asia for the treatment of pain, heart conditions, and cancer. We examined the concentrations of the main chemical constituents within a commercially available toad venom product and compared the levels for different extraction methods. Methods: Toad venom was extracted using either cold or hot water, ethanol (EtOH), methanol (MeOH), or ethyl acetate (EtOAc), was fractionated using precipitation or reflux, and was then analyzed using thin layer chromatography (TLC), high-performance liquid chromatography (HTLC), and liquid chroma-tography - mass spectrometry (LC-MS). Individual components were identified by comparisons of the retention times, the ultraviolet spectra, and mass spectras and differences in chemical constituents for different solvents and extraction methods are presented. Results: Components with authentic standards, including serotonin and bufodienolides (cinobufagen, bufalin, cinobufalin, and resibufogenin), were detected. The water extract of toad venom contained the greatest amount of serotonin ($75.7{\pm}0.1$ mg/g), but very small amounts of bufodienolides ($3.8{\pm}0.0$ mg/g). In contrast, the use of MeOH or EtOH extraction solutions resulted in 5-26 times higher concentrations of bufodienolides, with only trace amounts of serotonin. The relative and the absolute concentrations of the component also varied based on the extraction method; i.e., EtOH extracts yielded the greatest total amounts of bufodienolides, and EtOAc precipitation had the lowest amounts of bufodienolides. Conclusions: Toad venom consists of serotonin and several bufodienolides, and the choice of solvent to extract chemical the constituents is important as a way to enrich the purported active components for treating different conditions.

• 한국식품과학회지
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• 제13권1호
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• pp.37-42
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• 1981

우리나라에서 재배된 4가지 품종의 보리와 이들의 맥아에서 추출한 총지방질중 극성지질의 조성을 관, 얇은막 및 기체-액체 크로마토그래피로 분석한 결과를 요약하면 다음과 같다. 1. 4가지 품종의 보리와 이들 맥아의 총지방질중 당질의 평균함량은 8.9% 및 12.3%, 인지질의 평균함량은 17.3% 및 19.2%였으며, 보리중의 당지질 및 인지질의 함량은 맥아에서 평균 39.5% 및 11.5%가 증가하였다. 2. 보리의 당지질 중에는 DGDG 와 MGDG가 평균 35.5%및 28.6%로 주요성분이 었고 SG와 Cerebroside는 20.7% 및 15.2%이었으며, 보리중의 DGDG 와 MGDG 는 맥아에서 감소되었으나, SG 와 Cerebroside는 증가하였다. 3. 보리의 인지질 중에는 phosphatidyl choline(PC), lysophosphatidyl choline(LyPC), diphosphatidyl glycerol(DPG), phosphatidyl ethanolamine(PE)의 순으로 함유되어 있었으며, 맥아는 보리에 비하여 PC, LyPC는 감소하였으나 PE와 DPG는 증가하였다. 4. 보리와 맥아의 지방질중 당지질 및 인지질 획분의 지방산조성과 그 변화는 총지방질과 중성지질 획분의 지방산조성 및 그 변화 패턴과 비슷하였다. 그러나 당지질 획분중에는 리놀레산, 인지질 획분중에는 팔미트산의 함량이 다른 획분들에 비하여 많았다.

• 한국자원식물학회지
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• 제30권1호
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• pp.8-16
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• 2017

본 연구에서는 사구식물인 갯메꽃(Calystegia soldanella), 모래지치(Messerschmidia sibirica), 순비기나무(Vitex rotundifolia), 해당화(Rosa rugosa)의 잎과 줄기의 methanol 추출물에서 측정한 총 폴리페놀 함량은 해당화(110.20 mg/g)가 가장 높았고, 총 플라보노이드 함량은 순비기나무(38.07 mg/g)가 가장 높게 측정되었다. 추출물의 에틸아세테이트 분획물(조플라보노이드)을 이용하여 라디칼 소거능을 나타내는 DPPH, ABTS, FRAP assay로 항산화능을 측정하였다. 그리고 총 폴리페놀 / 플라보노이드 함량 (TFC/TPC) 비와 항산화능, 두 요인 사이의 상관관계에 대하여 분석하였다. TFC/TPC 비율이 매우 높았던 순비기 나무의 잎과 줄기는 항산화능 실험에서 대조군인 ascorbic acid 보다 떨어지는 것으로 나타났다. 하지만 가장 낮았던 해당화 잎이 DPPH, ABTS assay에서 가장 항산화능이 높았고, FRAP assay에서 모래지치 줄기가 가장 뛰어났다. 위 결과에서 항산화활성과 TFC/TPC 간의 상관관계를 통계적으로 유의하다는 점을 확인하여 TFC/TPC의 값이 직접적으로 항산화능에 기여 한다고 판단된다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.885-889
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• 2004

Fast and high-quality document clustering algorithms play an important role in providing data exploration by organizing large amounts of information into a small number of meaningful clusters. Hierarchical clustering improves the performance of retrieval and makes that users can understand easily. For outperforming of clustering, we implemented hierarchical structure with variety and readability, by careful selection of cluster topic words and deciding the number of clusters dynamically. It is important to select topic words because hierarchical clustering structure is summarizes result of searching. We made choice of noun word as a cluster topic word. The quality of topic words is increased $33\%$ as follows. As the topic word of each cluster, the only noun word is extracted for the top-level cluster and the used topic words for the children clusters were not reused.