• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2006년도 추계학술대회 논문집
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• pp.92-95
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• 2006

The global environment is deteriorating at an alarming rate despite of enhanced international environmental regulation. Many studies have been performed to reduce pollutants. Recently, phytoremediation, plant-based technology for the removal of toxic contaminants from soil, water, and air, has been receiving large attention. Arsenic-contaminated soil is one of the major pollutant sources fur drinking water. The fern brake (Pteris erotica) has been reported as a hyper-accumulate arsenic from soils. In this study, we investigated the arsenic absorption effect on sap flow inside xylem vessels of a fern brake. The synchrotron X-ray micro-imaging technique was employed to monitor flow inside the plant non-invasively. The captured phase-contrast X-ray images show both anatomy and transport of water inside the fern brake. The refilling process of water containing arsenic inside the xylem vessels of fern brake's leaves and stems was clearly observed. These results would provide important information needed fur understanding the mechanisms of accumulation, translocation, and transformation of toxic materials in plants.

• 한국가시화정보학회지
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• 제8권4호
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• pp.48-53
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• 2010

Water-uptake through roots, is an essential process of the water flow in plants. Its visualization is very useful for understanding sap flow dynamics at whole plant level. In this study, the tips of Arabidopsis' root hairs were excised and exposed to repeated dehydration and rehydration processes. The water-refilling through individual xylem vessels was visualized using the synchrotron X-ray micro-imaging technique. The high temporal resolution ($2\;{\mu}m$) and beam intensity of the X-ray source allowed to acquisition of consecutive X-ray images of the water-refilling process up to 10 frames/sec. Various flow patterns were observed and the ascending speed of the water-air interfaces was analyzed. The relation between the water-rising height and ascending speed was also analyzed. The present results would provide better alternative for investigating sap flows in roots.

• Journal of Microbiology and Biotechnology
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• 제28권12호
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• pp.2071-2078
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• 2018

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight, which results in severe economic damage to rice farms. Xoo produces biofilms for pathogenesis and survival both inside and outside the host. Biofilms, which are important virulence factors, play a key role in causing the symptoms of Xoo infection. In the present study, we investigated the nutritional conditions for biofilm formation by Xoo. Although Xoo biofilm formation may be initiated by interactions with the host, Xoo biofilm cannot mature without the support of favorable nutritional conditions. Nitrogen sources inhibited Xoo biofilm formation by overwhelming the positive effect that cell growth has on it. However, limited nutrients with low amino acid concentration supported biofilm formation by Xoo in the xylem sap rather than in the phloem sap of rice.

• 원예과학기술지
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• 제17권1호
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• pp.11-14
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• 1999

참다래 및 야생다래에서 수액 채취시기에 따른 수액특성, 수액내 유리당, 무기물 및 아미노산함량 변화를 조사하였다. 참다래 및 야생다래에서 수액 채취시기에 따른 수액량은 채취 시기가 늦을수록 심하게 감소하는 경향을 보였다. 수액내 수분함량, 당도, 점도 및 pH는 두 종간 차이가 없었으나 산함량 및 탁도는 야생다래보다는 참다래에서 다소 높은 경향을 보였다. 당은 참다래에서 fructose, glucose, sucrose, galactose, manitol이 함유되어 있었고 야생다래에서는 fructose, glucose가 함유되어 있었는데 당의 대부분은 fructose였다. 수액내 주요 무기물은 칼슘, 카리 및 마그네슘으로 칼슘함량이 상대적으로 가장 높았다. 두 종에서 각각 17종의 아미노산이 함유되어 있었는데 이들중 주요 아미노산은 glutamic acid, lysine 및 isoleucine이었는데 이중 glutamic acid함량이 가장 높았다. 참다래에서 histidine, methionine과 tylosine을 제외한 나머지 성분은 야생다래에 비해 높았다. 무기물 및 아미노산함량은 수액 채취시기가 늦을수록 증가하는 반면 유리당함량은 감소하는 경향을 보였다. 수액의 품질은 채취시기가 늦을수록 향상되는 것으로 나타났으나 수액채취량은 현저히 감소하는 경향을 보였다.

• Journal of Applied Biological Chemistry
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• 제43권3호
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• pp.170-175
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• 2000

A pot-lysimeter experiment was conducted with 3-year-old 'Tsugaru' apple (Malus domestica Borkh) trees to examine the changes in oxygen diffusion rate (ODR) with lateral flow velocity of water through soil. The influence of lateral water flow velocity on water relations and elemental content in leaf, and sap temperature distribution patterns of the xylem of trees were also determined. Trees were grown under four soil water regimes: (1) fast laterally flowing (FWT, $2.50{\times}10^{-4}cm\;s^{-1}$), (2) slow laterally flowing (SWT, $0.25{\times}10^{-4}cm\;s^{-1}$), and (3) stagnant water table (WLT) at 60-cm, and (4) drip-irrigation at -40 kPa of soil matric potential as a control. The rate of $O_2$ diffusion converged near $2{\times}10^{-3}g\;m^{-2}\;min^{-1}$ for FWT and control soils, but decreased below $1{\times}10^{-3}g\;m^{-2}\;min^{-1}$ 40 days after treatment (DAT) for WLT soils. For SWT soils, however, the ODR at 15 cm below the soil surface was similar to that of control, but at 45 cm below the soil surface, ODR was similar to that of the WLT treatment. Leaf water potential of FWT and SWT plants was similar to that of control plants, but the values for SWT plants declined by 98 DAT. Leaf water potential of WLT plants decreased from -1.86 MPa (9 DAT) to -2.41 MPa (59 DAT) and finally down to -2.70 MPa. The sap temperature measured at 1100-hr was lowest at top and highest at bottom for FWT and control plants, but this pattern of SWT and WLT plants was disturbed from 29 DAT. However, for SWT plants, such thermal disturbance of sap temperature disappeared from 63 DAT.

• KSBB Journal
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• 제32권2호
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• pp.117-123
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• 2017

Maple tree is a useful medical plant for obtaining bioactive materials such as pharmaceutics, cosmetics, food additive, etc., and there are 16 species of native maple trees in Korea. In this study, we evaluated the antioxidant activity of sap and crude extracts of Acer mono Max, a representative maple species. The crude extracts were obtained by solvent extraction (water, ethanol, and ethyl acetate) from its branches (bark and xylem). The phenolic contents and radical scavenging capacities of the extracts and the sap were evaluated in terms of half maximal effective concentration ($EC_{50}$) and kinetics by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The ethanol extracts showed the highest extraction yield, phenolic contents and antioxidant activity, and bark extracts showed better antioxidant activity than xylem extracts. The antioxidant activity of the sap was very low, but the $EC_{50}$ of ethanol and ethyl acetate extracts ranged from 68 to $79{\mu}g/mL$, similar to that ($60{\mu}g/mL$) of the control, butylated hydroxytoluene (BHT). The DPPH radical scavenging rate ($220{\sim}760{\mu}M/min$) and the second-order reaction rate constant ($6.48{\sim}7.04L/g{\cdot}min$) of these extracts were better than those of BHT ($55{\sim}370{\mu}M/min$ and $3.60L/g{\cdot}min$). These results suggest that A. mono Max. is one of the useful bioresources for obtaining antioxidant biologically active substances, and it is possible to obtain physiologically active substances from by-product of its pruning while minimizing the effect on the growth of the tree.

• Plant Resources
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• 제5권2호
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• pp.165-168
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• 2002

This study was carried out obtain basic information for growth characteristics by different age of Dendropanax morbifera in chonnam, such as Yosu, Sunchon, Haenam, Gangjin, Wando. The pH of soil in cultivation area was 5.2 to 5.6 and organic matter was very high up to 10.6% . P205 content of soil in cultivation area was 35.3 to 42.1 mg/L, C.E.S was 13.9 to 14.4 me/100g, and moisture rate was 19.2 to 21.1 % . The flowering of Dendropanax morbifera began from 6~7 years old tree. The flowering date was at 10th of July at Wando. The growth characteristics of 12 years old tree was 929.5cm in stem height, 134.1mm in stem diameter, and 15 years old tree was 1,117.9cm in stem height, 160.8mm in stem diameter. The number of leaf was 13.9 at five years old tree, and the petioles length was 12.6 at five years old tree. Xylem sap can be had at more than 10 years old tree with good growth more than 10 em stem diameter.

• Plant Resources
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• 제3권2호
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• pp.148-151
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• 2000

This study was carried out obtain basic information for growth characteristics by different age of Dendropanax morbifera in southern part of Korea, such as at Sunchon, Haenam, Gangjin, Wando. The pH of soil in cultivation area was 5.2 to 5.6 and organic matter was very high up to 10.6%. P$_{2}$O$_{5}$, content of soil in cultivation area was 35.3 to 42.1 mg/1, C.E.S was 13.9 to 14.4 me/100g, and moisture rate was 19.2 to 21.1 %. The flowering of Dendropanax morbifera began from 6~7 years old tree. The flowering date was at 10th of July at Wando. The growth characteristics of 12 years old tree was 929.5cm in stem height, 134.1mm in stem diameter, and 15 years old tree was 1,117.9cm in stem height, 160.8mm in stem diameter. The number of leaf was 13.9 at five years old tree, and the petioles length was 12.6 at five years old tree. Xylem sap can be had at more than 10 years old tree with good growth more than 10 cm stem diameter.r.

• Bulletin of the Korean Chemical Society
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• 제22권12호
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• pp.1375-1379
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• 2001

Monte Carlo simulations of hard-spheres confined in parallel hard walls have been carried out extensively at various densities and for various wall distances. The compressibility factors in the directions parallel and normal to the wall have been calculated from the radial free space distribution function (RFSDF) with the results showing that the compressibility factors normal to the wall are smaller than those in parallel direction and that a solid phase is formed in the direction normal to the wall while a fluid phase remains in the parallel direction. An order parameter is found to classify the phases whether a system (or a molecule) is in a fluid or a solid state. The compressibility factors of narrow wall are very small compared to those when the wall is put away. A plausible mechanism of the rise of sap in xylem vessel has been proposed.

• 한국토양비료학회지
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• 제17권4호
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• pp.349-355
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• 1984

대두(大豆)에서 유리질소(遊離窒素)의 고정(固定)과 밀접(密接)한 관련(關聯)을 갖고 있는 것으로 알려진 ureide 화합물(化合物)의 소장양상(消長樣相)을 품종간(品種間) 비교(比較)하기 위하여 세 가지 대두(大豆) 품종(品種)(황금(黃金)콩, williams79, 야생(野生)콩)을 공시(供試)하여 pot 재배(栽培)로 생육시간별(生育時間別) 식물체(植物體) 및 목질부(木質部) 분비액(分泌液) 중(中)의 ureide태(態)와 amide태(態) 질소화합물(窒素化合物)의 함량(含量) 변화(變化)를 조사(調査)하였으며 품종별(品種別) 이들 질소화합물(窒素化合物)의 함량(含量) 차이(差異)가 대두(大豆) 근류(根瘤)의 질소고정(窒素固定)에 대한 지표(指標)가 될 수 있는지를 일부(一部) 검토(檢討)하였다. 생장과정중(生長過程中) ureide 화합물(化合物)의 소장양상(消長樣相)은 공시품종간(供試品種間)에 비슷한 경향(傾向)으로 나타났으며 식물체(植物體)와 목질부(木質部) 분비액중(分泌液中)의 ureide 화합물(化合物)의 함량(含量)과 총가용성(總可溶性) 질소(窒素)에 대한 ureide태(態) 질소(窒素)의 함량비(含量比)는 전체적(全體的)으로 황금(黃金)콩에서 가장 높았고 다음이 williams79, 야생(野生)콩의 순서(順序)로 나타나 품종간(品種間)에 차이(差異)를 보였다. amide태(態) 질소(窒素)의 함량(含量)은 ureide태(態) 질소(窒素)와는 반대(反對)로 ureide태(態) 질소(窒素)의 함량(含量)이 가장 높았던 황금(黃金)콩에서 가장 낮았고 야생(野生)콩에서 가장 높았다. 이러한 차이(差異)는 식물체중(植物體中) 줄기 부분(部分)과 목질부분비액중(木質部分泌液中)에서 뚜렷이 나타났으며 이들 중(中)의 ureide태(態) 질소(窒素) 함량(含量)과 amide태(態) 질소(窒素) 함량(含量) 간(間)에는 높은 유의성(有意性) 있는 부(負)(일(一))의 상관관계(相關關係) ($r=-0.5193^{**}$, $-0.5053^*$)를 보였다. 질소(窒素)를 비료(肥料)로 따로 공급(供給)할 때 식물체중(植物體中) ureide태(態) 질소함량(窒素含量)이 감소(減少)하며 근류(根瘤)가 ureide 화합물(化合物)의 생성장소(生成場所)임을 감안(勘案)할 때 이상(以上)의 결과(結果)는 질소고정효과(窒素固定效果)의 차이(差異)를 나타내는 품종적(品種的) 특성(特性)으로 해석(解析)되며 줄기와 목질부(木質部) 분비액중(分泌液中)에서의 ureide태(態) 질소(窒素)의 함량(含量)을 두과작물(豆科作物)의 질소고정효과(窒素固定效果)에 대한 지표(指標)로 이용(利用)할 수 있을 것이며 또한 정량적(定量的)으로 질소고정력(窒素固定力)을 측정(測定)하는 수단(手段)으로도 응용(應用)할 수 있는 가능성(可能性)을 추구(追究)할 의의(意義)가 있을 듯하다.