• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.1
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• pp.27-34
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• 2023

In this study, spent mushroom substrate (SMS), which consits of lignocellulosic material, was pretreated by hydrothermal method; the changes of biodegradability and methane production yield of pretreated SMS were determined according to formation of lignocellulosic biomass degrading byproducts formation during thermal pretreatment. Based on the results, all hydrothermal pretreatment temperatures showed improved solubilization performance for biomass, and the optimum pretreatment effect was observed at an pretreatment temperature of 150℃ with the highest methane production yield. However, the induced formation of furan derivatives (i.e., 5-hydroxymethylfurfural and furfural) as byproducts during hydrolysis of hemicellulose and cellulose at severe condition lowered biodegradability and methane yield when the hydrothermal pretreatment temperature was higher than 180℃. Thus, this study revealed that hydrothermal pretreatment could promote anaerobic digestion efficiency of lignocellulosic biomass and is of great importance for preventing byproducts formation through pretreatment condition control.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.83-91
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• 2006

Reduction kinetics and the behaviour of intermediate of three high explosives (HMX, RDX, and TNT) were studies in batch reactors using nano- or micro- size zero valent iron(nZVI or mZVI) as reducing agent. The kinetic constants normalized by the mass of iron ($k_M$) or by the surface area ($k_{SA}$) were measured and compared along with the changes in the concentrations of intermediates. Results showed that $k_M$ and $k_{SA}$ values were not suitable to fully explain the behaviour of mother compounds and reduced intermediates in the batch reactor. The concentrations of initial explosives degradation products, such as nitroso-RDXs, nitroso-HMXs, and hydroxylamino-TNTs, were higher in mZVI treated reactor than in nZVI treated reactor, whereas more reduced polar intermediates such as TAT were accumulated in the nZVI reactor. Therefore, a new parameter, which accounted for the intermediates reduction, needs to be developed.

• KOREAN POULTRY JOURNAL
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• v.16 s.174
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• pp.44-48
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• 1984

축산물을 소비자에게 효율적으로 공급하기 위하여 유통의 중간 단계로서의 역할과 기능을 수행하는 도매시장이 필요하다

• Microbiology and Biotechnology Letters
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• v.2 no.3
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• pp.127-131
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• 1974

Inhibition of over-oxidation of prednisolone in the fermentation has been studied by using vegetative cells as enzyme source. firstly, A. simplex (ATCC 6946) was demonst.ated to degrade p.ednisolone in the vegetative culture of the microorganism. Over 72％ of hydrocortisone was transformed into prednisoloneby 3 hours of the fermentation. However, the prednisolone produced was considerably oxidized forming over-oxidation product in 8hours of fermentation period with the intact cells. Secondly, in order to depress the over-oxidation and the breakdown of the steroid skeleton of prednisolone, chelating agents such as $\alpha$$\alpha$'-dipyridyl, o-phenanthroline and 8-hydroxyruinoline were added to the fermentation broth. Conseauently, the breakdown of prednisolone by the iutact cells was able to be remarkably retatded and an intermediate regarded as an oxidized product derived from prednisolone was accumulated, by the addition of $\alpha$$\alpha$'-dipytidyl in the fermentation.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.6
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• pp.389-393
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• 2013

The purpose of this study is to investigate the biodegradation characteristics of the xylene by BTEX-degrading bacteria, Pseudomonas putida BJ10, isolated from oil-contaminated soil and bio-degradation pathway of the xylene. The removal efficiencies of o, m, p-xylene in mineral salts medium (MSM) by P. putida BJ10 were 94, 90 and 98%, respectively for 24 hours. It shows clear difference compared with the control groups which were below 3%. The removal efficiencies of BTEX by P. putida BJ10 in gasoline-contaminated soil were 66% for 9 days. They were clearly distinguished from the control groups (control and sterilized soil) which were 32 and 8%. 3-methylcatechol and o-toluic acid were detected after 6 and 24 hours during the o-xylene biodegradation pathway. Therefore, we confirmed o-toluic acid as the final metabolite. And intermediate-products were somewhat different with previously published studies of the transformation pathway from o-xylene to 3-methylcatechol.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.47-53
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• 2004

Feasibility of electrokinetic process combined with Fenton-like reaction was investigated for the removal of phenanthrene from contaminated soil. Transport of hydrogen peroxide by electroosmosis and decomposition of phenanthrene by Fenton-like reaction were observed in a model system. Electrical potential gradient and electroosmotic flow (EOF) at 10 mA were higher than those at 5 mA. High accumulated EOF resulted in high removal efficiency of phenanthrene because the large amount of hydrogen peroxide was transfered through the soil. Removal efficiency of phenanthrene by water washing was 8.5% for 7 days. The highest removal efficiency including phenanthrene decomposition was 95.6% for 14 days. After the operation, soil samples with removal efficiency of 95.6% showed low concentrations of phenanthrene and its intermediates. From this result, it was presumed that phenanthrene was decomposed to small molecules or mineralized to water and carbon dioxide due to continuous supply of hydrogen peroxide by electroosmotic flow.

• The Korean Journal of Nuclear Medicine
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• v.27 no.2
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• pp.277-284
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• 1993

$^{99m}Tc$-MAG3는 세뇨관 배설을 하는 신장 기능 영상용 방사성의 약품으로서, 가운데 $^{99m}Tc$이 있고 1개의 유황과 3개의 질소가 아래쪽 면에 정사각형으로 배치되고 정점에 산소가 위치한 4각 피라미드형을 하고 있다. 그러나 시판되는 신장 영상용 MAG3는 반응성이 강한 -SH기에 의한 부산물 생성을 방지하기 위해 benzoyl기로 보호되어 있으므로 보통 조건으로는 잘 표지되지 않고 10분 정도 끓여주어야 한다. 본 실험에서는 실온에서도 benzoyl기를 잘 끊어지게 하는 이미다졸, 아고마틴, 괴리딘등과 같은 염기성 촉매제를 가하고 여러가지 PH에서 실온에서 반응시켜 본 결과, benzoyl기가 끊어지면서 $^{99m}Tc$과 -SH기가 반응하는 첫번째 반응이 일어난 후에도 산성에서 약알칼리성 범위에서는 중간체가 상당량 생성되고 알칼리성 (pH 10.5)이 되어야 최종 산물로 재빨리 넘어가는 것을 발견하였다. 또한 glucarate, medronate, phthalate, acetate 등 여러가지 다른 transchelating agent를 사용하여 같은 반응을 시킨 후에도 생성된 중간체의 HPLC 피크가 같은 retention time (Rt)을 보이는 것으로 보아 이 중간체의 화학구조내에는 transchelating agent를 포함하지 않는 것으로 보인다. 최종 생성물과 중간체의 ImM 시트테인 용액 중에서의 안정도 시험을 하여 본 결과 최종 생성물은 매우 안정하나 중간체는 불안정한 것을 발견하였다.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.3
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• pp.46-51
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• 2008

The traditional view of the fate of lignin under anaerobic conditions is that it is recalcitrant because molecular oxygen is required for depolymerization. The presence of lignin is apparently the most important factor affecting the biodegradability of ligneous materials. The initial step in the degradation of ligneous material to smaller intermediates is catalyzed by enzymes secreted by microorganisms and is generally regarded as the rate limiting step in the microbial mineralization of organic matter. Biochemical methane potential (BMP) test, typically used to assess anaerobic biodegradability of liquid wastes with added nutrients and bacteria, have been adapted to assess initial biodegradation of ligneous material under anaerobic conditions. A method based on selective inhibition of microorganism activity, by 3% toluene, has been used to measure using the initial degradation rate of ligneous material and the accumulation of lignin-derived compounds.

• Journal of KIISE:Databases
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• v.33 no.7
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• pp.682-692
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• 2006

Searching for gene products which have similar biological functions are crucial for bioinformatics. Modern day biological databases provide the functional description of gene products using Gene Ontology(GO). In this paper, we propose a technique for semantic similarity search for gene products using the GO annotation information. For this purpose, an information-theoretic measure for semantic similarity between gene products is defined. And an algorithm for semantic similarity search using this measure is proposed. We adapt Fagin's Threshold Algorithm to process the semantic similarity query as follows. First, we redefine the threshold for our measure. This is because our similarity function is not monotonic. Then cluster-skipping and the access ordering of the inverted index lists are proposed to reduce the number of disk accesses. Experiments with real GO and annotation data show that GORank is efficient and scalable.

• KSBB Journal
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• v.4 no.1
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• pp.8-10
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• 1989

Mutagenic characteristics deactivation of 7, 12-dimethylbenz(a)anthraracene was studied in a nonacclimated sandy loam soil at low and neutral pH soil conditions. Soil extracts containing transformation products were separated into three fractions based on HPLC retention time(polarity). Highly polar transformation products of 7, 12-dimethylbenz(a)anthracene demonstrated a negative mutagenic response with the Ames mutagenicity assay, strain TA-100, for both low and neutral pH soils. Moderate and low polar fractions, however, induced mutagenicity for both soil samples with mutagenic ratios similar to those of the parent compound.