• Title/Summary/Keyword: natural exposure

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Suppressive effects of ethanol extract of Aralia elata on UVB-induced oxidative stress in human keratinocytes (자외선 B를 조사한 인간유래각질세포에서 두릅순 에탄올추출물의 산화적 스트레스 억제효과)

  • Kwak, Chung Shil;Yang, Jiwon
    • Journal of Nutrition and Health
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    • v.49 no.3
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    • pp.135-143
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    • 2016
  • Purpose: Ultraviolet (UV)-induced oxidative stress contributes to several adverse biological effects on skin. Many phenolic phytochemicals have been shown to have antioxidant properties and protect skin cells from UV-induced oxidative damage. In this study, we investigated whether or not Aralia elata (AE) has a protective effect against UVB-induced reactive oxygen species (ROS), ultimately leading to photoaging. Methods: Phenolic content of dried AE and antioxidant properties of AE extract in 70% ethanol weredetermined by measuring DPPH and ABTS radical scavenging activities and ferric reducing antioxidant power (FRAP). The effect of AE extract on cellular ROS generation and expression levels of oxidative stress-response proteins such as superoxide dismutase (SOD)-1, catalase, nuclear factor-erythroid 2-related factor (Nrf)-2, and heme oxygenase (HO)-1 in UVB-irradiated ($75mJ/cm^2$) human keratinocytes (HaCaT) were further determined by 2'-7'-dichlorofluoresceine diacetate assay and Western blotting, respectively. Results: The total phenolic and flavonoid contents of dried AE were 20.15 mg tannic acid/g and 18.75 mg rutin/g, respectively. The $IC_{50}$ of AE extract against DPPH radical was $98.5{\mu}g/mL$, and ABTS radical scavenging activity and FRAP upon treatment with $1,000{\mu}g/mL$ of AE extract were $41.8{\mu}g\;ascorbic\;acid\;(AA)\;eq./mL$ and $29.7{\mu}g\;AA\;eq./mL$,m respectively. Pretreatment with AE extract significantly reduced (p < 0.05) ROS generation compared to that in UVB-irradiated control HaCaT cells. Pretreatment with AE extract reversed reduction of Nrf-2 and SOD-1 protein expression and induction of HO-1 protein expression caused by UVB exposure in HaCaT cells, whereas it did not affect catalase expression. Conclusion: AE extract in 70% ethanol demonstrated a protective effect against UVB-induced oxidative stress and decreased expression of Nrf-2 and SOD-1 in human keratinocytes. These findings suggest that AE ethanol extract might have potential as a natural resource for a skin anti-photoaging product in the food and cosmetic industry.

Effect of the Space Dose Rate due to Change of X-ray Irradiation Energy and MU Value in Radiation Therapy Room (선형가속기의 엑스선 조사에너지와 MU값의 변화가 치료실 내 공간선량률 변화에 미치는 영향)

  • Kwon, Hyeonghyo;Park, Geonryul;Kim, Minji;Jo, Yeongdan;Kim, Youngjae
    • Journal of the Korean Society of Radiology
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    • v.14 no.2
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    • pp.77-83
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    • 2020
  • This study investigated the radiation protection of therapeutic radiologists. Based on the change in X-ray energy and MU value, the space dose rate in the treatment room after the irradiation was measured. 6MV, 10MV and 15MV photon beams were exposed to radiation inside the treatment room based on 300MU, 600MU and 1000MU using a linear accelerator. And repeated 10 times under the same conditions. As a result of the experiment, 0.1555 μSv/h for 6MV 300MU, 0.157 μSv /h for 300sec, 0.152 μSv/h, 0.156 μSv/h for 600MU, and 0.157 μSv/h 0.152 μSv/h for 1000MU. 300MU of 10MV was 0.49 μSv/h, 0.309 μSv/h, and 0.69 μSv/h, 0.416 μSv/h for 600MU, respectively, and 1000MU was 0.977 μSv/h and 0.478 μSv/h, respectively. The 300MU of 15MV was 3.02 μSv/h, 1.2 μSv/h, 5.459 μSv/h at 600MU, 7.34 μSv/h at 1.836 μSv/h 1000MU, and 2.709 μSv/h. The average spatial dose rate of 6MV was not significantly different from the natural spatial dose rate in the treatment room. High spatial dose rates were measured at 10 MV and 15 MV and were attenuated over time. Therefore, entering the treatment room after a certain period of time (more than 60 seconds) is considered to be effective to prevent the exposure dose of radiation workers.

Effect of Resveratrol on the Induction of Cdk Inhibitor p21 and Pro-apoptotic Bax Expression by amyloid-β in Astroglioma C6 Cells (신경교 세포에서 resveratrol이 amyloid-β에 의해 유도되는 Cdk inhibitor p21 및 Bax 발현의 감소 효과)

  • Kim Young Ae;Lim Sun-Young;Ko Woo Shin;Choi Byung Tae;Lee Yong Tae;Rhee Sook-Hee;Park Kun-Young;Lee Won-Ho;Choi Yung Hyun
    • Journal of Life Science
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    • v.15 no.2 s.69
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    • pp.169-175
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    • 2005
  • Resveratrol (3,4',5-trihydroxy-trans-stilbene), a phytoalexin found in grape skins, peanuts, and red wine, has been reported to have a wide range of biological and pharmacological properties. $Amyloid-\beta$ deposition and senile plaque-associated astrocytes are common neuropathological features of Alzheimer's disease. In this study, we have explored the effects of resveratrol on $amyloid-\beta-peptide-mediated$ cytotoxicity in vitro and modulation of cell growth-regulatory gene products in astroglioma C6 cells to elucidate its possible mechanism for anti-cytotoxicity. Exposure of C6 cells to $Amyloid-\beta$ resulted in dose-dependent growth inhibition and morphological changes of C6 cells, which were recovered by pre-treatment with resveratrol. The anti-proliferative effect of $amyloid-\beta$ was associated with the induction of tumor suppressor p53 and cyclin-dependent kinase (Cdk) inhibitor p21 (WAF1/CIP1) expression assessed by RT-PCR and Western blot analysis in time-dependent manner in C6 cells. In addition, the pro-apoptotic Bax expression was also up-regulated in $amyloid-\beta-treated$ C6 cells without alteration of anti-apoptotic Bcl-2 and $Bcl-X_L$ expression. However, pre-treatment of resveratrol significantly inhibited $amyloid-\beta-induced$ p53, p21 and Bax levels, suggesting that the modulation of p53, p21 and Bax levels could be one of the possible pathways by which resveratrol functions as anti-cytotoxic agent. Our results demonstrate that resveratrol may enhance the protection against $amyloid-\beta-induced$ cytotoxicity by promoting the survival of glial cells.

Study of Antidotes on the Nephrotoxicity of Ochratoxin A (Ochratoxin A의 신장독성감소 방법에 대한 연구)

  • 서경원;김준규;김태완;정세영;김효정
    • Journal of Food Hygiene and Safety
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    • v.13 no.2
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    • pp.121-128
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    • 1998
  • Ochratoxin A (OA) is a mycotoxin produced by Aspergillus ochraceus as well as other molds. It is a natural contaminant of mouldy food and feed. OA has a number of toxic effects, the most prominant being nephrotoxicity. Futhermore, OA is immunosuppressive, genotoxic, teratogenic and carcinogenic. OA inhibits protein synthesis by competition with phenylalanine in the phenylalanine-tRNA aminoacylation reaction. Recently, lipid peroxidation induced by OA has been reported, indicating that the lesion induced by this mycotoxin could be also related to oxidative pathway. Since it seems impossible to avoid contamination of foodstuffs by toxigenic fungi, detoxification and detoxication of OA are needed. In this study we investigated the protective effects of aspartame (Asp), phenylalanine (Phe), polyphenol 70S (PP) and aloe extract (AE) on the nephrotoxicity induced by subacute exposure to the OA. Asp and Phe are structural analogues of OA. PP, an ingredient of Green Tea and AE have been known as antioxidant and radical scavenger. Phe (40 mg/kg, i.p.) and Asp (25 mg/kg, p.o.) were administered to Sprague-Dawley rats simultaneously with OA (2.0 mg/kg, p.o.) for 2 weeks. PP (200 mg/kg, p.o.) and AE (50 mg/kg, i.v.) were pretreated before administration of OA, for 2 weeks and 3 days, respectively. Using enzymuria, BUN level, creatinemia and histophathologic examination as indices of renal damage, we observed that all of four compounds prevented the nephrotoxic effects induced by OA. It seems that structural analogues of OA such as Asp and Phe have better protective effect on the nephrotoxicity of OA than antioxidants. These results indicate that 1) formation of free radical and lipid peroxidation are likely to be involved in the nephrotoxicity of OA in vivo, 2) Asp, PP and AE might be used for prevention of renal lesions in cases of ochratoxicosis.

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Characteristics of Pesticide Runoff and Persistence on Agricultural Watersheds in Korea (영농지역에서 작물재배 형태에 따른 농약의 잔류성과 유출특성)

  • Park, Byung-Jun;Kwon, Oh-Kyung;Kim, Jin-Kyoung;Kim, Jin-Bea;Kim, Jin-Ho;Yoon, Soon-Kang;Shim, Jae-Han;Hong, Moo-Gi
    • Korean Journal of Environmental Agriculture
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    • v.28 no.2
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    • pp.194-201
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    • 2009
  • To evaluate the exposure of non-point source pesticide pollution in agricultural watershed and to investigate pesticide distribution and runoff from agricultural land, paddy field, upland and orchard, this experiment was carry out during crop growing seasons. The pesticide were detected twenty pesticides fungicide 4, insecticide 10, herbicide 6) in water of Neungchon agricultural watershed and detection concentrations were range 0.008${\sim}$7.59 ppb. Most of the detection pesticides were using pesticides to rice paddy fields to control fungi, insects, weeds. During the crop cultivation, the pesticide were detected total thirty pesticides by pepper field soil 6, orchard soil 4, sesame field soil 3 and rice paddy field soil 5, and pesticide concentrations were range 0.001${\sim}$0.109 ppm. Especially the herbicides were detected mainly in May and June in the stream water. The pesticide were detected thirty pesticides by fungicide 2, insecticide 6, herbicide 5 in water of Jungam Koseong agricultural watershed and detection concentrations were range 0.01${\sim}$7.21 ppb. In regard to the detected pesticides, the concentration of individual pesticides measured in surface water of the study areas never exceeded guidelines for agriculture chemicals concerning water quality-effluent from paddy fields in Japan (Katayama, 2003). Runoff rate of pesticides was range 0.07${\sim}$3.06 % from Kongju agricultural land to watershed after applied pesticides.

The Responses of Particulate Phosphorus Exposed to the Fresh Water in Marine Sediment (담수화로 인한 퇴적물 내 입자성 인의 거동에 관한 실험적 연구)

  • Ji, Kwang-Hee;Jeong, Yong-Hoon;Kim, Hyun-Soo;Yang, Jae-Sam
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.2
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    • pp.84-90
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    • 2009
  • We incubated marine columnar sediments at $25^{\circ}C$ for 230 days to simulate the responses of phosphorus in the sediment which was exposed to freshwater. The incubation was composed of three different treatments (FW: freshwater, FWA: freshwater under anoxic condition, and SW: seawater as a Control). Six particulate fractions of phosphorus in sediment were obtained through sequential extraction and, for comparison, phosphate concentrations in porewater and superlying water were also determined. After the incubation, evidently higher concentrations of phosphate were found in FW and FWA compared to SW. Mass extinction of living organisms in marine sediment from freshwater shock and consequent decay of their corps probably contributed such high phosphate spike in the overlying water. Higher concentrations of BD-P(lron-bound P) were found in FW compared to SW. After exposure to the freshwater, we could determine that penetration depth of dissolved oxygen in marine sediment will be deeper. A result of increases of ferrous compounds in freshwater where contained less sulfide has been obtained. Because of these phenomena, BD-P was increased in FW. On the contrary, BD-P was decreased in FWA since poor dissolved oxygen concentration. In FWA, total amount of Leachable P(SUM of LOP) has been remarkably increased through the experiment, which strongly suggested the easy conversion of the leachable P into reactive P. This experiment has shown that most of diverse P species in marine sediment were leachable under freshwater and low oxygen condition. Therefore reclamation of natural tidalfalt and consequent freshwater introduction seems to trigger the conversion of diverse P-species to leachable P in the marine sediments, which will exert high benthic load of phosphate to the overlying water.

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Comparative Analysis of Ecological Health Conditions Before and After Ecological Restoration in Changwon Stream and Nam Stream (창원천.남천에서 생태복원 전.후의 생태건강도 비교평가)

  • Kim, Hyun-Jeong;Lee, Sang-Jae;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.307-318
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    • 2010
  • This study was to analyze the ecological conditions, based on physical habitat, chemical, and biological conditions before (2006, 2007) and after ecological restoration (2009) in five sites of Changwon Stream (CS) and six sites of Nam Stream (NS), respectively, and then to compare ecological health between the two period. The analysis of ecological health was based on the multimetric models of Index of Biological Integrity (IBI) and Qualitative Habitat Evaluation Index (QHEI) along with water chemistry in the streams. For the study, the models of IBI and QHEI were modified as 8 and 11 metric attributes, respectively. For the evaluations, the survey was conducted in the period of 2006~2007 before the restoration and in 2009 after the restoration by the city. Chemical conditions, based on conductivity, in both streams showed a typical longitudinal declines along the axis of the upstream-to-downstream. There were no significant differences (p>0.05) in water quality between the two periods. Values of IBI in the CS and NS averaged 21.6 and 19.7, respectively, indicating a C grade in the criteria of Ministry of Environment, Korea, and there was no significant differences in the IBI between the two periods. Values of QHEI after the restoration averaged 29.2 and 63.2 in the CS and NS, respectively and the values decreased markedly especially, in the NS (35.3) after the restoration. The habitat disturbance was mainly attributed to destructions (i.e., the narrower width of riparian vegetation and higher substrate exposure by the air) of artificial materials by massive flood in 2009. Overall, our results suggest that the restoration was not effective in the two streams between the two periods, even if the budget was used a lot and that such ecological restoration, not considered the natural disaster, may not effect for the stream restoration.

Analysis Corrosion Products Formed on the Great Buddha Image of Kotokuin Temple in Kamakura (고덕원 국보 동조아미타여래좌상의 표면에 생성한 부식생성물의 해석)

  • Matsuda Shiro;Aoki Shigeo;Kang, Dai-il
    • 보존과학연구
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    • s.17
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    • pp.161-182
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    • 1996
  • In natural atmosphere, copper and copper alloy have been used to make buddha statues and ornaments of historic buildings since the abovementioned metals have corrosion resistance in some extent, and the patinaformed on the surface of the metals has provided the people aesthetic satisfaction with its beauty. But in atmosphere polluted by $SO_x$and $NO_x$, the patina layer does not work as a protective film, and it allows damages of the metal. Since 1992, Tokyo National Research Institute of Cultural Properties(TNRICP)has conducted studies on the influence of atmospheric pollution on metal cultural property held under open air. The Great Buddha Image which is located in Kamakura about 50km west from Tokyo, has been selected as one of the objects to study because it is made by copper alloy and it has stood exposed in the air for about a few hundreds years. Furthermore it is also the reason to study on it that there are many cultural properties in the surroundings of it. We have analysed the components and the structure of the corrosion products formed on the surface of the Buddha, have carried out exposure tests using the alloy samples which have simulated the components of the Great Image, and have observed climated and polluted air in order to discuss the relation between corrosion of metals in open air and conditions of the atmosphere. In this paper, the authors have described the components and the structure of the corrosion product formed on the surface of the Great Image by means of X-ray fluorescence spectroscopy and X-ray diffraction. The conclusions are as follows. (1) Sulfate patina composed mainly with brochantite were detected on the all sides of the Image and the amount of the patina is found more on the back of the Image facing to north. (2) Antlerite were detected on the back and a park of the left side facing to west, and formation of it was considered to have close relation with malignant atmosphere. (3) A big amount of chloride patina which mainly composed of atacamite were observed on the front facing to south. (4) Carbonate patina mainly composed of malachite were detected on the area where brochantite was often detected as well. It suggested that malachite had been transformed into brochantite by deteriorated atmosphere. (5) On the all sides of the Image, patina were observed together with copper oxides mainly composed of cuprous oxide. It showed that the surface layer of the Image consists of two layers : inner layer of oxide and outer layer of patina. (6) Corrosion products of lead which was a component of copperalloy were detected on the all sides : the main lead product found on the front was chlorophosphate whereas the one on the back was sulfate.

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Synergistic effect of ionizing radiation and $\beta$-lapachone against tumor in vitro and in vivo

  • Park, Eun-Kyung;Kim, Young-Seok;Lee, Sang-wook;Ahn, Seung-Do;Shin, Seong-Soo;Park, Heon-Joo;Song, Chang-Won
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.80-80
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    • 2003
  • ${\beta}$-lapachone(${\beta}$-Lap), a natural o-naphthoquinone, presents in the bark of the Lapacho tree. ${\beta}$-Lap is cytotoxic against a variety of human cancer cells and it potentiates the anti-tumor effect of Taxol. In addition, ${\beta}$-Lap has been reported to radiosensitize cancer cells by inhibiting the repair of radiation-induced DNA damage.In the present study, we investigated the cytotoxicity of ${\beta}$-Lap against RKO human colorectal cancer cells as well as the combined effect of ${\beta}$-LaP and ionizing radiation. An incubation of RKO cells with 5 ${\mu}$M of ${\beta}$-Lap for 4 h killed almost 90% of the clonogenic cells. An incubation of RKO cells with 5 ${\mu}$M of ${\beta}$-Lap for 4 h or longer also caused massive apoptosis. Unlike other cytotoxic agents, ${\beta}$-Lap did not increase the expression of p53 and p21 and it suppressed the NFkB expression. The expression of Caspase 9 and 3 was minimally altered by ${\beta}$-Lap. Radiation and ${\beta}$-Lap acted synergistically in inducing clonogenic cell death and apoptosis in RKO cells when ${\beta}$-Lap treatment was applied after but not before the radiation exposure of the cells. Interestingly, a 4 h treatment with 5 ${\mu}$M of ${\beta}$-Lap starting 5 h after irradiation was as effective as that starting immediately after irradiation. The mechanisms of ${\beta}$-Lap-induced cell killing is controversial but a recent hypothesis is that ${\beta}$-Lap is activated by NAD(P)H: quinone-onidoreductase (NQO1) in the cells followed by an elevation of cytosolic Ca$\^$2+/ level and activation of proteases leading to apoptosis. It has been reported that NQO1 level in cells is markedly up-regulated for longer than 10 h after irradiation. Indeed, using immunological staining of NQO1, we observed a significant elevation of NQO1 expression in RKO cells 5h after 2-4 Gy irradiation. Such a prolonged elevation of NQO1 level after irradiation may be the reasons why the ${\beta}$-Lap treatment applied S h after irradiation was as effective as that applied immediately after irradiation in killing the cells. In view of the fact that the repair of radiation-induced damage is usually completed within 1-2 h after irradiation, it is highly likely that the ${\beta}$-Lap treahment applied 5 h after irradiation could not inhibit the repair of radiation-induced damage. For in vivo study, RKO cells were injected S.C. into the hind-leg of Nu/Nu mice, and allowed to grow to 130 mm3 tumor. The mice were i.p. injected with ${\beta}$-lapachone or saline 2 h after irradiation of tumors with 10 Gy of X-rays. The radiation induced growth delay was increased by 2.4 $\mu\textrm{g}$/g of ${\beta}$-lapachone. Taken together, we may conclude that the synergistic interaction of radiation and ${\beta}$-Lap in killing cancer cells is not due to radiosensitization by ${\beta}$-Lap but to an enhancement of ${\beta}$-Lap cytotoxicity by radiation through an upregulation of NQO1. The fact that NQO1 is elevated in tumors and that radiation causes prolonged increase of the NQO1 expression may be exploited to preferentially kill tumor cells using ${\beta}$-Lap in combination with radiotherapy.

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Vegetation Structure and Site Characteristics of Rhododendron brachycarpum Population in South Korea (남한에서 만병초(Rhododendron brachycarpum D. Don ex G. Don) 개체군의 식생구조와 입지 특성)

  • Hwang, Yong;Han, Mu-Seok;Kim, Yong-Yul;Kim, Mu-Yeol
    • Korean Journal of Environment and Ecology
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    • v.28 no.6
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    • pp.751-761
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    • 2014
  • This study was carried out to analyze the vegetation properties, soil characteristics and ordination of Rhododendron brachycarpum population in South Korea. Rhododendron brachycarpum were mainly distributed along the Ulleungdo and Baekdudaegan of the Korean penninsula and it's population was located at an elevation of 872m to 1466m. The Rhododendron brachycarpum population was classified into Taxus cuspidata var. latifolia dominant population, Magnolia sieboldii dominant population, Thuja koraiensis dominant population and Rhododendron brachycarpum typical population. The composition of soil properties in the same areas are as follows: organic matter, total nitrogen, available phosphorous, exchangeable $K^+$, exchangeable $Ca^{2+}$, exchangeable $Mg^{2+}$ contained, and soil pH. The capacities of these chemical properties of the soil ranged from 10.45~15.28%, 0.37~0.61%, $0.21{\sim}0.35cmol^+/kg$, $0.39{\sim}2.54cmol^+/kg$, $0.17{\sim}0.50cmol^+/kg$, $18.28{\sim}22.81cmol^+/kg$ and 4.66~5.23 respectively. The results of the correlation between communities and soil conditions of vegetation of Rhododendron brachycarpum by DCCA ordination method are as follows: Taxus cuspidata var. latifolia dominant population was found in the very steep sloped area that has low percentage of total organic matter and nitrogen than other populations. Magnolia sieboldii dominant population and Thuja koraiensis dominant population was found in the steep sloped area that has high percentage of total organic matter and nitrogen than other populations. Thuja koraiensis dominant population was found in the gentle sloped area that has high percentage of altitudinal and rock exposure. Current status of Rhododendron brachycarpum is very vulnerable with a collection of herbs constantly threatening the species' survival. Thus, concrete conservation plans to protect natural habitats should be set up as soon as possible.