• 한국환경과학회지
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• 제4권2호
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• pp.201-214
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• 1995

Design approach of upflow Anaerobic Sludge Blanket(UASB) process based on the biological kinetic parameters are known to be very difficult since the characteristics of the granular slut비e depends on the type of wastewater and size distribution of the granular sludge also depends on the upflow velocity in the UASB reactors. Furthermore, industrial wastewater containing toxic substances has been treated by UASB process without the clear knowledge of toxic effects on the granular slut형e. Hence, the present research was aimed on the intensive evaluation of biological kinetic parameters of the granular sludge in UASB reactor with and without toxic substance of 2, 4-dichlorophenol in order to present the basic design measures for UASB process design. The results could be summarized as follows. The biological kinetic parameters(k and Ks) considerably varied with the granular size of the sludge. Generally, 연e k and ks values of the granular sludge increased with the particle size of the granule. The biological kinetic parameters(k and Ks) of the granular sludge obtained from batch test were not applicable to design purpose of UASB process due to substrate diffusional limitation into the granular sludge in the completely mixed UASB reactors. The toxic effects on k and Ks greatly varied with the granular sixte. And as the toxicant concentration increased, the k value decreased while the Ks value increased. Inhibition constant(hi) for k with the toxicant of 2, 4-dichlorophenol varied from 0.5 to 2.3 depending on the granular sizes while the inhibition constant(Ki) for Ks varied from 20.7 to 80.1, showing the mixed inhibition.

• 한국잔디학회:학술대회논문집
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• 한국잔디학회 2011년도 제24차 정기총회 및 학술발표회
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• pp.35-35
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• 2011

A large patch disease caused by Rhizoctonia solani AG2-2(IV) is a serious problem in turfgrass sites including golf courses and sports fields in Korea. The objectives of this study were to isolate some antagonistic microorganisms and to explain some involving mechanisms. Initially single colonies which were formed from the filtrates of various soil samples were obtained from LB culture and then co-cultured with R.solani AG2-2(IV) on PDA plate to explore some antagonistic microbes against for large patch fungus, Rhizoctonia solani AG2-2(IV). Out of total 82 antagonistic isolates which commonly had inhibition effect on Rhizoctonia solani AG2-2(IV) mycelial growth, one candidate (YPIN22) showed the most antifungal effect, which was confirmed by the longest distance from the edge of bacterial colony to the mycelial edge of the Rhizoctonia solani AG2-2(IV) in the dual culture. A succeeding investigation was to test any potential effect of the isolate on growth inhibition of 5 other turfgrass pathogens including R. solani solani AG2-2(IIIB), P. ultimum, C. caudatum, C. lunata, and F.oxysporum. Preliminary result indicated that the new isolate YPIN22 was also found to have antagonistic potential on the growth inhibition of those turfgrass pathogenic fungi, which was explained by inhibition zones ranging from 8 to 22mm. A further explanation of some characteristics of the isolate YPIN22 will be discussed in detail.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 1999년도 춘계학술발표회 초록집
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• pp.18-18
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• 1999

• 한국응용곤충학회지
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• 제31권2호
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• pp.122-132
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• 1992

신규화합물의 in Vitro AChE 저해력을 평가하기 위한 저해시험법의 확립을 목적으로 실험을여 다음과 같은 결과를 얻었다. {TEX}$I_{50}${/TEX} 산출이 가능한 고정시간 저해시험(fixed time inhibition test)의 경우, DFP, DDVP 및 paraoxon과 같은 대표적 AChE 저해제의 저해력 평가에 적당한 저해시간은 10분 정도로 조사되었으며, 10분간의 저해조건하에서 ester group을 보유한 신규화합물의 저해여부 및 정도의 평가에 효과적인 시험농도는 10$\mu$M 수준으로 판정되었으나 다른 화합물의 경우에는 보다 높은 농도로부터 단계적 저해시험이 필요한 것으로 보였다. {TEX}$K_{d}${/TEX}, {TEX}$k_{3}${/TEX} 및 {TEX}$k_{i}${/TEX}와 같은 저해상수의 산출을 위한 경시적 저해시험(Progressive inhibition test)에 있어서, 본 실험의 장시간 저해(0.8~13.3분)와 낮은 저해제농도(1$\times${TEX}$10^{-9}${/TEX}~2$\times${TEX}$10^{-6}${/TEX}M)의 조건하에서는 극히 낮은 {TEX}$K_{d}${/TEX}(1.3$\times${TEX}$10^-{8}${/TEX}~5.6$\times${TEX}$10^{-7}${/TEX}M) 및 {TEX}$K_{3}${/TEX}(0.21~{TEX}$0.27min^{-1}${/TEX})가 관찰되었으나 저해제간의 저해독성 조사에는 충분한 타당성을 가지는 것으로 조사되었다. 또한 DFP, paraoxon 및 신규화합물인 KH501간의 현격한 저해력 차이는 {TEX}$K_{d}${/TEX}의 차이 즉, 저해제와 AChE간의 친화력 차이에 기인된 것으로 판명되었다. 따라서 AntiChE 스크리닝에 있어서 1차단계에서는 고정시간 저해법을 통하여 산출된 {TEX}$I_{50}${/TEX}를 바탕으로 하여 저해력 유무 및 정도를 파악하고, 1차단계에서 고도의 AChE 저해력이 인정된 신규 화합물을 대상으로 2차단계인 경시적 저해법을 이용하여 저해양상 및 특성을 조사하는 것이 합리적인 체계일 것으로 생각되어진다.

• 한국잡초학회지
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• 제18권4호
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• pp.314-324
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• 1998

신규로 합성한 cyclohexanedione계 화합물 EK3143과 EK3150의 제초작용 발현의 특성을 기존약제와 비교조사하고, 이들이 ACCase에 대해 어떠한 저해활성을 가지는지를 알아보고자 제반실험을 수행하였다. Sethoxydim은 화본과식물에만 제초효과를 가지며 생육정지와 함께 조직의 황화, 괴사가 나타난다, 반면에 Ek3143과 EK3150은 화본과식물에 대한 활성은 상대적으로 감소되었으나 까마중, 어저귀 등의 광엽잡초에 대해서는 보다 강한 활성을 가졌다. EK3143은 저농도의 보다 폭넓은 범위에서는 백화증상이, 고농도에서는 sethoxydim과 동일한 증상을 나타내었고 EK3150은 모든 농도에서 식물체의 백화를 유기시켰으며 광엽잡초의 경우 분열조직에서 그 증상이 뚜렷하였다. 이들 화합물의 화본과식물에 대한 생육저해 활성과 옥수수 ACCase에 대한 저해정도간에는 일치된 경향을 보였으나 광엽잡초인 어저귀와 까마중에 대한 ACCase 활성과 전식물체(intact plant)에서의 제초활성간에는 일치된 경향을 보이지 않았다. 즉 EK3143과 EK3150은 어저귀와 까마중의 ACCase에 대한 저해활성이 sethoxydim보다 전반적으로 높은 특징을 보이지만, 광엽잡초에 대한 제초활성이 상대적으로 높았던 EK3150이 ACCase에 대해서는 EK3143보다 오히려 낮은 저해활성을 나타내었다. 한편 색소감소 정도가 신장저해보다 빨리 나타나는 norflurazon 및 EK3140 처리에서와는 달리, EK3143과 EK3150 처리에서는 색소감소 보다 신장저해가 보다 빠르게 나타나 다른 저해양상을 보였다. 이상의 결과로 보아 EK3143 EK3150은 ACCase 이외에 다른 작용점을 추가로 저해하는 것으로 생각되며, 약간의 구조변경에따라 제초작용점간의 결합정도에 차이가 생김으로써 생육저해 또는 백화증상이 서로 비중을 달리하여 나타나는 것으로 추정된다.

• 한국식품조리과학회지
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• 제33권1호
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• pp.65-71
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• 2017

Purpose: This study was carried out to investigate the availability of raw Astragalus membranaceus as a food ingredient. Methods: Raw and dried A. membranaceus water extracts were used to examine the free radical scavenging activity, polyphenol and flavonoid contents, and antimicrobial activity. Also, the sensory characteristics of each water extracts were evaluated. Results: The free radical scavenging activity and total polyphenol and flavonoid contents of raw A. membranaceus extracts were higher than those of dried A. membranaceus extracts. The antimicrobial activities of raw and dried A. membranaceus extracts were examined against several food borne illness-causing microorganisms using the paper disc diffusion method. Inhibition zones were observed in Staphylococcus aureus subsp. aureus, Bacillus subtilis, Pseudomonas aeruglnosa, Salmonella enterica subsp. enterica, Escherichia coli and Bacillus cereus treated with raw extracts. Inhibition zones were observed in B. subtilis, P. aeruglnosa and S. enterica subsp. enterica treated with dried extracts. Raw A. membranaceus extracts had higher scores than dried extracts in sensory evaluation. Conclusion: Raw A. membranaceus was better in antioxidative, antimicrobial activities, and sensory characteristics than dried one.

• 사상체질의학회지
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• 제31권1호
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• pp.36-64
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• 2019

Introduction The purpose of this study was to review thirty years of studies on psychological characteristics of Sasang types to delineate generalizable psychological theories pertaining Sasang typology. Methods Research articles providing psychometric characteristics of each Sasang types were extracted from five database written in Korean and English. Demographic features of the participants, clinical methods for the Sasang type classification, and psychological characteristics of each Sasang types were reviewed and summarized. Results A total of 59 peer-reviewed research articles were found to be published from 1991 to 2018, and the So-Yang and So-Eum Sasang type showed distinctive and contrasting psychological features. The overlap between Eastern and Western psychology in Behavioral Activation and Inhibition System was highlighted as for personality studies, but the anxiety as a pathological factor was not found distinguishable between Sasang types. Discussion The present systematic review provided insight on psychological perspectives of Sasang typology, and would be useful for establishing unique construct of Korean Psychology.

• Corrosion Science and Technology
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• 제12권2호
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• pp.65-78
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• 2013

The present investigation deals with the corrosion inhibition of mild steel in 1M $H_2SO_4$ with 1, 4-dihydro pyridine and its derivatives prepared using microwave activation method. The synthesis of inhibitor was confirmed by IR spectra. The effect of 1, 4-dihydropyridine derivatives on the corrosion inhibition of mild steel in 1M $H_2SO_4$ was studied using weight loss and electrochemical polarization techniques. Influence of temperature (303-333K) and synergistic effect of halide ions ($I^-$, $Br^-$ and $Cl^-$) on the inhibition behaviour was also studied. Corrosion products on the metal surface were analyzed by scanning electron microscopy (SEM) and a possible mechanism of inhibition by the compounds is suggested. Thermodynamic parameters were calculated using weight loss data in order to elaborate the mechanism of corrosion inhibition. Polarization measurements revealed that the studied compounds acted as mixed type inhibitor but slightly anodic in nature. Electrochemical impedance measurements revealed that the compounds were adsorbed onto the carbon steel surface and the adsorption obeyed the Langmuir adsorption isotherm. The synergistic effect of halide ions on the IE increases with increase in concentration. The IE obtained from atomic absorption spectrophotometric studies was found to be in good agreement with that obtained from the conventional weight loss method. SEM revealed the information of a smooth, dense protective layer in presence of the inhibitors.

• Journal of Microbiology and Biotechnology
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• 제6권6호
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• pp.445-450
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• 1996

Gelatinase A is a member of the matrix metalloproteinases that play an important role in cancer invasion and metastasis. In the course of screening gelatinase A inhibitors from microbial sources, a fungal strain PT-262 showed a strong inhibitory activity. The strain was identified as Chaunopycnis alba on the basis of its morphological characteristics. The inhibitor was isolated from acetone extract of mycelial cake by sequential chromatographies on MCI-gel, Sephadex LH-20, and a reverse-phase HPLC column. The purified inhibitor was identified as pyridoxatin by its physico-chemical properties and spectroscopic analysis. Pyridoxatin is not a peptide analog and has cyclic hydroxamic acid moiety. It inhibited activated gelatinase A with an $IC_{50}$ value of 15.2 ${\mu}M$ using fluorescent synthetic peptide. It also had a strong cytotoxicity against human cancer cell lines in vitro. Furthermore, this compound inhibited DNA synthesis with an $IC_{50}$ value of 2.92 ${\mu}M$ in PC-3 prostate cancer cells by [$^3H$]thymidine incorporation assay.

• 생명과학회지
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• 제24권4호
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• pp.377-385
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• 2014

본 연구는 남해특화작목인 섬애약쑥의 활용도를 높이고 건강식품 소재로서의 가능성을 제시하기 위하여 음건한 섬애약쑥과 일정기간 발효시킨 섬애약쑥의 이화학적 성분을 비교하고, 물과 에탄올 추출물(30%, 50%, 70%, 100%)을 제조하여 항산화 활성과 tyrosinase 및 xanthine oxidase 저해 활성을 측정하였다. 수율은 섬애약쑥 30% 에탄올 추출물에서 29.74%로 가장 높았으나 총 페놀 및 플라보노이드 함량은 섬애약쑥 70% 에탄올 추출물에서 각각 72.25 mg/g 및 33.34 mg/g으로 가장 높았다. 항산화 활성을 측정한 결과 모든 추출물에서 농도가 증가함에 따라 그 활성이 증가하였으며, 특히 섬애약쑥 70% 에탄올 추출물은 DPPH, ABTS 라디칼 소거능 및 ${\beta}$-carotene linoleic 탈색 방지 효과가 가장 우수하였다. Tyrosinase 저해 활성은 $500{\mu}g/ml$ 농도에서 섬애약쑥 70% 에탄올 추출물이 50.01%로 가장 높았으나 100% 에탄올 추출물은 11.44%로 가장 낮았다. Xanthine oxidase 저해 활성은 $250{\mu}g/ml$ 농도에서 섬애약쑥 물 추출물이 60% 이상으로 가장 높았다. 이상의 결과를 종합하여 볼 때, 섬애약쑥은 발효하지 않았을 때 항산화 활성이 더 우수하였으며, 70% 에탄올로 추출할 경우 가장 항산화 효과가 높았다. 또한, 섬애약쑥 추출물은 tyrosinase 및 xanthine oxidase 저해에도 상당한 효과를 가지며, 이러한 결과는 페놀 및 플라보노이드 함량과 상관관계가 높은 것으로 판단된다.