• Journal of the Korean Wood Science and Technology
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• 제6권1호
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• pp.3-7
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• 1978

중간부후균(中間腐朽菌)인 Lentinus edodes (Berk) Singer에 의(依)한 졸참나무의 성분(成分) 분해(分解)에 미치는 영향(影響)을 조사(調査)하기 위(爲)해 건전재(健全材) 종균(種菌)을 접종(接種)한 후 2년(年)및 5년(年)을 경과(經過)한 3종류(種類)의 골목을 시료(試料)로 사용(使用)한 결과(結果)는 다음과 같다. 1) 탄수화물(炭水化物) 부분(部分)에 주(主)로 분해(分解)를 일으키며, 알카리 추출물(抽出物)의 증대(增大) 및 결정화도(結晶化度)의 감소(減少)는 목재(木材)의 변질분해(變質分解) 사실(事實)을 더욱 확실(確實)히 한다. 2) 크라손리그닌의 정량(定量), 켈 여과(濾過), 니크로벤젠 산화등(酸化等)의 결과(結果)에 의(依)하면 리그닌도 대단(大端)히 변질(變質) 분해(分解)받고 있다고 생각할 수 있다. 한편MWL의 메톡실기(基)의 감소(減少), 카르복실기의 증가(增加)는 탈(脫)메칠화(化)와 산화(酸化)가 평행(平行)한다고 설명할 수 있다. 3) 니트로벤젠산화(酸化)의 결과(結果) S/V 치(値)가 적은 것으로 보아 시링길핵(核) 단위(單位)가 바닐린 보다 비교적(比較的) 분해(分解)하기 쉽다고 생각된다. 또한 알데이하이드기(基)에 비(比)해 카르복실(酸)(시링길산(酸))의 증가(增加)는 생분해(生分解)에 의(依)해 산화(酸化)가 진행(進行)하고 있다는 것을 뜻한다.

• Journal of Applied Biological Chemistry
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• 제50권4호
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• pp.281-287
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• 2007

Microorganisms were isolated from earthworm intestine and examined for their ability to degrade 3-methyl-4-nitrophenol (MNP), a main degradation product of the insecticide fenitrothion. An isolate that showed the best degradation of MNP was selected for further study. The 16S rRNA analysis showed that the isolate belongs to the genus of Burkholderia, close to phenanthrene-degrading Burkholderia sp. S4.9, and is named Burkholderia sp. SH-1. When time-course degradation of MNP by SH-1 was examined by high performance liquid chromatographic analysis, almost complete degradation of MNP was observed within 26 h. Colony forming unit value assays indicated that the isolate SH-1 was capable of utilizing MNP as a sole carbon source. SH-1 could also degrade p-nitrophenol (PNP) but could not degrade ortho-substituted nitroaromatics such as 2,4-, 2,6- and 2,5-dinitrophenol. Catechol was detected as the main degration product of MNP and PNP. SH-1 was also found in the soil from which earthworms were obtained. These results suggest that the dispersal of Burkholderia sp. SH-1 into different environment with the aid of earthworms is likely to play a role in bioremediation of the soil contaminated with MNP.

• Archives of Plastic Surgery
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• 제35권1호
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• pp.7-12
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• 2008

Purpose: Since the report of artificial dermis manufacturing method using collagen by Yannas in 1980, collagen has been effectively used as dermal substitute with its merits such as, lower antigeneicity, controllable biodegradation rate, and minimal inflammatory cytotoxic properties in the dermal tissue engineering field. However, weak mechanical durability was the main drawback of collagen dermal substitute. To improve its stability, mechanical or chemical cross-linking was used. Despite of such process, its clinical use was restricted due to weak durability. To improve the durability of collagen matrix, we designed elastin-incorporated collagen matrix and compared its durability with conventional collagen matrix. Methods: 15mm diameter with 4mm thick collagen dermal matrix was made according to Yannas protocol by mixing 0.5% bovine collagen and chondroitin-6-sulfate followed by degassing, freeze drying, dehydrodermal cross-linking and chemical cross-linking procedure. In elastin incorporated collagen matrix, same procedure was performed by mixing elastin to previous collagen matrix in 4:1 ratio(collagen 80% elastin 20%). In comparison of the two dermal matrix in vitro tests, matrix contracture rate, strain, tensile strength, was measured and stiffness was calculated from comparative analysis. Results: In terms of matrix contracture, the elastin-incorperated added collagen dermis matrix showed 1.2 times more contraction compared to conventional collagen matrix. However, tensile strength showed 1.6 times and stiffness showed 1.6 times increase in elastin-incorporated matrix. Conclusion: Elastin incorperated collagen matrix manufactured by our team showed increased durability due to improvement in tensile strength and stiffness compared to previous collagen matrix($Integra^{(R)}$).

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.28-30
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• 2005

Because of high population diversity in soil microbial communities, it is difficult to accurately assess the capability of biodegradation of toxicant by microbes in soil and sediment. Identifying biodegradative microorganisms is an important step in designing and analyzing soil bioremediation. To remove non-important noise information, it is necessary to selectively enrich genomes of biodegradative microorganisms fromnon-biodegradative populations. For this purpose, a stable isotope probing (SIP) technique was applied in selectively harvesting the genomes of biphenyl-utilizing bacteria from soil microbial communities. Since many biphenyl-using microorganisms are responsible for aerobic PCB degradation In soil and sediments, biphenyl-utilizing bacteria were chosen as the target organisms. In soil microcosms, 13C-biphenyl was added as a selective carbon source for biphenyl users, According to $13C-CO_2$ analysis by GC-MS, 13C-biphenyl mineralization was detected after a 7-day of incubation. The heavy portion of DNA(13C-DNA) was separated from the light portion of DNA (12C-DNA) using equilibrium density gradient ultracentrifuge. Bacterial community structure in the 13C-DNAsample was analyzed by t-RFLP (terminal restriction fragment length polymorphism) method. The t-RFLP result demonstates that the use of SIP efficiently and selectively enriched the genomes of biphenyl degrading bacteria from non-degradative microbes. Furthermore, the bacterial diversity of biphenyl degrading populations was small enough for environmental genomes tools (metagenomics and DNA microarrays) to be used to detect functional (biphenyl degradation) genes from soil microbial communities, which may provide a significant progress in assessing microbial capability of PCB bioremediation in soil and groundwater.

• 한국물환경학회지
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• 제21권2호
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• pp.141-146
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• 2005

The aim of this study is to quantify and characterize the dissolved organic carbon (DOC) from paddy fields and crop fields in Tottori, Japan. DOC and ultraviolet (UV) absorption were measured in the filtrated water of each sample. The DOC concentration and the SUVA (specific UV absorption) of biodegradation analysis samples were determined around 50 days after their incubation. In the Fukui paddy fields, DOC concentration varied seasonally from 1.1 to $10.1mg\;Cl^{-1}$, becoming higher during heavy runoffs in April, a non-agriculture period. Variations in DOC concentration did not always correspond to rainfall, though. The Obadake paddy fields showed a DOC concentration pattern similar to that of the Fukui paddy fields. The daily DOC discharge per area in the Fukui (up), Fukui (down), Obadake (south) and Obadake (north) paddy fields influent from paddy fields were 0.02, 0.0161, 0.0135 and $0.0027kg\;a^{-1}day^{-1}$, respectively. These differences resulted from differences in agricultural types and customs of farmers according to paddy fields and other kinds of fields. Also, the SUVAs [which are indirect means to evaluate humic substances (hydrophobic fractions)] of the studied influent waters from paddy fields were generally lower than those of the influent waters from crop fields. Nonbiodegradable DOC accounted for 50.2 - 98% and 46.8 - 85.5% of the total DOC in the paddy fields and in the crop fields, respectively.

• 한국물환경학회지
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• 제33권6호
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• pp.754-768
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• 2017

Polybrominated diphenyl ethers (PBDEs) are a group of industrial aromatic organobromine chemicals that have been used since the 1970s as flame retardants in a wide range of consumer products and articles, including plastics, computers, textiles and upholstery. Commercial PBDEs were added to Annex A of the Stockholm Convention as persistent organic pollutants in May 2009. PBDEs are still frequently found in sludge and effluent from wastewater treatment plants, even though commercial PBDEs were prohibited or voluntarily phased out several years ago. Conventional wastewater treatment processes are not designed to effectively remove PBDEs. This indicates that there is an urgent need for new developments and improvements to enhance upon the treatment techniques which are currently available. Several studies have suggested the potential removal and degradation technologies for PBDEs in wastewater. In this study, the concentrations and compositional profiles of PBDE congeners in sludge and effluent are investigated by analyzing the relevant literature data in relation to their usage patterns in commercial products in North America and South Korea. The strengths and weaknesses of the current PBDEs removal techniques (i.e., biodegradation, zero-valent iron, photolysis, sorption, etc.) are discussed critically. In addition, future research direction regarding the treatment and removal of PBDEs from wastewater is also suggested, based on the literature review.

• 미생물학회지
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• 제37권1호
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• pp.66-71
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• 2001

1.5 L 교반 탱크반응조에서 이미 그 특성 이 밝혀진 TNT 분해세균인 Stenorophomonas maltophilia의 배양을 이용하여 dinitrotoluenes (DNTs) [2,4-dinitrotoluene (2,4-DNT), 2,6-dinitrotoluene (2,6-DNT)]를 호기적 조건하에서 미생물학적으로 제거하는 시험을 하였다. 2,4-DNT와 2,6-DNT는 각각 10일과 14일의 배양기간 중에 완전히 분해되었다. 이차 탄소는 DNT리 분해에 필수적이었으며 이차 탄소가 없는 상태에서는 거의 분해되지 않았다. DNTs의 분해에 이차 탄소가 미치는 효과에 대하여 조사하였다. 이차 질소원이 없는 상태에서 DNTs는 완전히 분해되었으나 이차 탄소원이 첨가된 배지에서는 부분적으로 분해되었다. HPLC와 GC-MS가 잔존 DNTs와 중간대사산물을 확인하기 위하여 사용되었다. 그 결과, HPLC와 GC-MS chromatograms은 대상 화합물인 2,4-DNT와 2,6-DNT, 그리고 각각의 중간대사산물인 2-amino-4-nitrotoluene과 2-amino-6-nitrotoluene을 성공적으로 확인할 수 있었다.

• 분석과학
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• 제5권2호
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• pp.159-167
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• 1992

하천수 중 LAS의 각 동족체 및 이성체들의 성분을 BP-5 capillary column을 이용한 GC 및 GC/MS에 의하여 분리 확인 및 정량하였다. 특히 LAS 유도체의 mass chromatogram에 의해 RIC에서는 분리가 되지 않는 $5-C_{11}$과 $6-C_{11}$ 및 $2-C_{12}$, $6-C_{13}$과 $7-C_{13}$의 LAS 성분을 각각 분리 확인하였다. 중랑천, 진위천 및 한강 하루부에서 채수한 시료 중에서 탄소수 $C_{10}$, $C_{11}$, $C_{12}$ 및 $C_{13}$의 LAS 성분을 측정하였으며 동족체 및 이성체의 조성비를 구하였다. 표준품과 하천수 중 LAS 성분의 함량비를 측정 비교함으로써 하천에서 LAS의 생분해 및 동태를 추정할 수 있었다.

• 환경생물
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• 제17권2호
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• pp.147-152
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• 1999

본 연구에서는 현재 국내에서 사용되고 있는 이분해성 미생물 분해성 시험방법의 문제점을 제시하고 이를 해결하거나 보완할 수 있는 방법을 제안하고자, OECD지침서에 등재된 6가지 이분해성 시험방법 중 시험물질의 선정에 제한이 없는 MITI(I), manometric respirometry, closed bottle test에 대하여 8개 화학물질을 대상으로 비교시험 하였다. 현재 국내에서는 MITI(I)법을 사용하고 있는데 이 방법은 접종미생물의 준비과정과 배양유지에 많은 시간과 비용을 요구하며, 배양과정을 통해 미생물의 종이 단순화되는 단점을 지니고 있다. 접종 미생물의 채취와 화학물질의 선택에 제한이 없는 새로운 방법으로는 manometric respirometry법을 들 수가 있는데, 시험방법의 용이성과 경제성, 재현성 등을 모두 고려할 때 가장 적합한 방법이라고 사료된다.

• 한국환경복원기술학회지
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• 제21권1호
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• pp.133-143
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• 2018

In spite of the growing importance of landscaping trees, the rate of flawed and withered trees damaged by pest, disease, drought or frost is increasing. In order to evaluate the performance of the Tree Protective Pad, which are developed to reduce the failure ratio in landscape planting, the tree protective pad for 'digging', 'pest controlling', and 'insulating' are tested based on the five functional criteria; moisturizing effect, wither preventive effect, pest and disease control, thermal effect, tensile strength, and environmental performance. The result of this study is as follows. The moisturizing effect of the tree protective pad for digging is found to be outstanding. According to the result of testing the pad on trees, in particular, it is better than jute tape in wither preventive effect, which means it is expected to prevent flaw and wilt from planting during the improper seasons like summertime. The experiment of installing the protective tree pad for pest controlling to the trunk of Quercus mongolica shows that preventive effect of the pad from diseases and insects is superior, and it also has economical effect by reducing the use of agricultural chemicals. The comparative test of the pad for insulating and jute tape proves that the temperature of the pad is about $2^{\circ}C$ higher than outside. The rate of tensile strength and biodegradation of the pad exceeds the optimal level, so it is revealed that the pad may be the work efficient and environment-friendly product. Likewise, by timely irrigating trees, the tree protective pad economically prevents trees from pest, disease,drought or frost, which may be caused by improper seasonal or delayed planting. As a means of reducing the flaw and facilitating the growth of trees, the exceptional performance of the pad is expected to effectively used in landscape planting and management.