• 한국지반환경공학회 논문집
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• 제15권5호
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• pp.39-46
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• 2014

본 연구에서는 다양한 호기/혐기조건에서 유류오염물질인 및 MTBE의 생분해 특성을 비교하고, 특히 탈질 조건에서 질산염 영향을 조사하여 유류오염지역의 혐기적 자연정화방법의 적용 가능성을 평가하고자 한다. 단일기질 및 혼합기질 분해실험 결과, BTEX는 3가지 실험조건에서 차이는 있었으나 모두 분해가 일어났다. 그러나 benzene과 p-xylene은 호기성 조건에서 초기 공급된 용존 산소의 부족으로 인하여 분해가 지연되는 것으로 나타났다. 또한 혼합기질에서는 단일기질에 비해 BTEX 분해가 기질 경쟁관계로 인해 다소 지연되는 경향이 관찰되었다. MTBE는 탈질 조건에서만 생분해가 관찰되었으나, TBA 축적 없이 $CO_2$로 무기화되는 것으로 추정된다. 또한 BTEX 및 MTBE 분해에 대한 질산염 농도의 영향 실험 결과, 저농도(>50 mg/L)에서 BTEX 분해는 제한되었으며, 고농도 질산염(<200 mg/L) 조건하에서는 BTEX 분해가 억제되는 현상이 관찰되었다. 본 연구에서 도출된 결과는 유류오염지역의 경우 호기/혐기성 조건에서 자연 생분해를 유도할 수 있을 것으로 예상된다.

• 미생물학회지
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• 제30권4호
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• pp.260-264
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• 1992

2, 4, 5-T 분해균주인 Pseudomonas sp. EL-071P 는 rifampicin, ampicilin, kanamycin 등의 중금속에 대하여 내성을 가지고 있었다. 이 균주로부터 2, 4, 5-T 분해능과 rifampicin 의 내성에 관련된 하나의 plasmid 를 분리, 정제하였으며 그 크기는 약 40 kb 이었다. E. coli 에 2, 4, 5-T 분해능에 관ㅎ련된 plasmid 를 transformation 한 결과 2, 4, 5-T 분해에는 plasmid 가 관여함을 확인할 수 있었다. 이 균주는 다양한 염소계방향족 동족체화합물을 유일한 탄소원으로 하여 생육할 수 있었으며, chlorophenol compound 의 경우 CI$^{-}$ 의 치환위치가 ortho, para-, meta- 위치순으로 분해가 잘 되었다. 2, 4, 5, -T 의 기질 유사체인 4-chlorophenol 에 의해 2, 4, 5-T 대사가 저해되었다. 비염소계 방향족화합물중 benzoate, salicylate, toluene 은 Pseudomonas sp. EL-071P 와 Pseudomonas putida KCTC 1643 에 의해 탄소원으로 이용되었으나 naphtalene 의 경우 Pseudomonas sp. EL-071 에 의해서만 탄소원으로 이용되어 표준균주인 Pseudomonas putida KCTC 1643 과 상이한 결과를 나타내었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권4호
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• pp.62-69
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• 2014

In the results of monitoring nitrate concentration in more than 8,000 groundwater wells around agro-livestock, the average and maximum nitrate concentration was 9.4 mg/L and 101.2 mg/L, respectively. Since about 31% of the monitoring wells was exceed the quality standard for drinking water, nitrate control such as remediation or source regulation is required to conserve safe-groundwater in South Korea. Typical nitrate-treatment technologies include ion exchange, reverse osmosis, and biological denitrification. Among the treatment methods, biological denitrification by indigenous microorganism has environmental and economic advantages for the complete elimination of nitrate because of lower operating costs compared to other methods. Major mechanism of the process is microbial reduction of nitrate to nitrite and nitrogen gas. Three functional genes (nosZ, nirK, nirS) that encode for the enzyme involved in the pathway. In this work, we tried to develop simple process to determine possibility of natural denitrification reaction by monitoring the functional gene. For the work, the functional genes in nitrate-contaminated groundwater were monitored by using PCR with specific target primers. In the result, functional genes (nosZ and nirK) encoding denitrification enzymes were detected in the groundwater samples. This method can help to determine the possibility of natural-nitrate degradation in target groundwater wells without multiplex experimental process. In addition, for field-remediation application we selected nitrate-contaminated site where 200~600 mg/L of nitrate is continuously detected. To determine the possibility of nitrate-degradation by stimulated-natural attenuation, groundwater was sampled in two different wells of the site and nitrate concentration of the samples was 300 mg/L and 616 mg/L, respectively. Fumarate for different C/N ratio was added into microcosm bottles containing the groundwater to examine denitrification rate depending on carbon concentration. In the result, once 1.5 times more than amount of fumarate stoichiometry required was added, the 616 mg/L of nitrate and 300 mg/L of nitrate were completely degraded in 8 days and 30 days. The nitrite, byproduct of denitrification process, was also completely degraded during the experimental period.

• 대한의용생체공학회:의공학회지
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• 제10권2호
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• pp.89-90
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• 1989

To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed and produced a composite that is consisted of calcium phosphate and collagen. Human umbilical cord origin pepsin treated type I atelocollagen was used as the structural matrix, by which sintered or non-sintered carbonate apatite was encapsulated to form an inorganic-organic composite. With cross linking atelocollagen by UV ray irradiation, the resistance to both compressive and tensile strength was increased. Collagen degradation by the collagenase induced collagenolysis was also decreased.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
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• pp.138.1-138
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• 2000

No Abstract, See Full Text

• 한국표면공학회지
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• 제21권1호
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• pp.47-52
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• 1988

The purpose of th this study was to determine an adsorption capaty of cesium by domestic zeolite, clinoptilolite, which has adsorption selectivity and resistence to radiolytic degradation, and to find the operation of column packed natural or Na cinoptiloite. The exchange capacity of cesium was 0, 875 m eq-per gram of clinopilolite. Na clinoptilolite was mire effective for cesium removal than naturl clioptilolite. Then, the results show that the domestic cilnoptilolite activated with sodium hydroxide colud be applicable for removal of cesium from liquid radwastes.

• Archives of Pharmacal Research
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• 제20권1호
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• pp.17-23
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• 1997

A saline suspension of Lumbricus rubellus earthworm powder (EWP) was administered to rats (1 g/kg/day) orally for 15 days to evaluate an oral effectiveness for thrombotic disorders. Blood was drawn at 2-day interval after the administration. Several parameters for antithrombotic, anticoagulant and fibrinolytic activities were measured, including platelet aggregation, clotting time, plasmin activity and the levels of FDP (fibrin/fibrinogen degradation products), D-dimer, and t-PA antigen. It did not affect platelet aggregation induced by ADP and collagen but anticoagulant activity (aPTT and TT) was gradually increased to two-folds for the first 5 days of administration and back to normal. Fibrinolytic activity of euglobulin fraction was highest on the 11 th day after the administration. The level of FDP was elevated to be comparable to the positve control$ (5-10 {\mu}g/ml)$ after 9-day treatment. Oral administration of the EWP could also reduce the formation of venous thrombus induced with viper venom. Complete blood count (CBC) profiles were within normal ranges except for a slight increase in white blood cells after the oral administration for 15 days. These results suggested that the EWP may be valuable for the prevention and/or treatment of thrombotic diseases.

• IMMUNE NETWORK
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• 제10권6호
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• pp.212-218
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• 2010

Backgroud: The stem bark of Kalopanax pictus (KP) has been used in traditional medicine to treat rheumatoidal arthritis, neurotic pain and diabetes mellitus in China and Korea. In this study, the mechanism responsible for anti-inflammatory effects of KP was investigated. Methods: We examined the effects of KP on NO production, nitric oxide synthase (iNOS) and HO-1 expression, NF-${\kappa}B$, Nrf2 and MAPK activation in mouse peritoneal macrophages. Results: The aqueous extract of KP inhibited LPS-induced NO secretion as well as inducible iNOS expression, without affecting cell viability. KP suppressed LPS-induced NF-${\kappa}B$ activation, phosphorylation and degradation of $I{\kappa}B-{\alpha}$, phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK). Furthermore, KP induced HO-1 expression and Nrf2 nuclear translocation. Conclusion: These results suggest that KP has the inhibitory effects on LPS-induced NO production in macrophages through NF-${\kappa}B$ suppression and HO-1 induction.

• Journal of the Korean Wood Science and Technology
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• 제48권1호
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• pp.107-116
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• 2020

Termiticidal and fungicidal activities of wood vinegar from Cinnamomum parthenoxylon (CP) stem wood have been evaluated against Coptotermes curvignathus and wood rotting fungi (Schizophyllum commune and Fomitopsis palustris). The utilized CP wood vinegar was produced in the operating temperature range 250-300℃ pyrolysis. A no-choice test was applied for evaluating termiticidal activity with 33 active termites and antifungal activity using the agar media assay. The result showed that an increase in the concentrations of CP wood vinegar significantly raised the mortality of termite. CP wood vinegar showed high termiticidal activity, organic acids (acetic acid 42.91%, 3-butenoic acid 6.89%, butanoic acid, 2-propenyl ester 2.26%), and ketones (1-hydroxy-2-propanone 5.14%, 3-methylcyclopentane-1,2-dione 2.34%) might be largely contributed to termiticidal activity in addition to other minor components. Furthermore, CP wood vinegar exhibited significant inhibition of fungal growth. These data showed that CP wood vinegar was more toxic to white-rot fungi (S. commune) than brown-rot (F. palustris). The results suggested that phenolic compounds from lignin degradation were responsible for good antifungal activity.

• 에너지공학
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• 제27권3호
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• pp.63-67
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• 2018

The Democratic People's Republic of Korea, or the DPRK, is one of the poorest country in world facing chronic economic, energy and food security issues. Prolonged improper management of economic and natural resources has led to extreme poverty, malnutrition and critically vulnerability to nature's forces. Presistent deforestation and forest degradation in the DPRK has national and global consequences which has attracted attention from international community, whose offering financial and technical assistance for targeted interventions. Through REDD+ programs, the DPRK has the opportunity to establish its credentials as a responsible nation while improving the quality of life of its population. This study offers an enabling context under which suitable climate change action related to forestry can be identified and implemented in the DPRK.