• Journal of Microbiology and Biotechnology
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• v.21 no.6
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• pp.627-636
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• 2011

A commercially important alkaline protease, produced by Bacillus sp. RRM1 isolated from the red seaweed Kappaphycus alvarezii (Doty) Doty ex Silva, was first recognized and characterized in the present study. Identification of the isolated bacterium was done using both biochemical characterization as well as 16S rRNA gene sequencing. The bacterial strain, Bacillus sp. RRM1, produced a high level of protease using easily available, inexpensive agricultural residues solid-state fermentation (SSF). Among them, wheat bran was found to be the best substrate. Influences of process parameters such as moistening agents, moisture level, temperature, inoculum concentration, and co-carbon and co-nitrogen sources on the fermentation were also evaluated. Under optimized conditions, maximum protease production (i.e., 2081 U/g) was obtained from wheat bran, which is about 2-fold greater than the initial conditions. The protease enzyme was stable over a temperature range of 30-$60^{\circ}C$ and pH 6-12, with maximum activity at $50^{\circ}C$ and pH 9.0. Whereas the metal ions $Na^+$, $Ca^{2+}$, and $K^+$ enhanced the activity of the enzyme, others such as $Hg^{2+}$, $Cu^{2+}$, $Fe^{2+}$, $Co^{2+}$, and $Zn^{2+}$ had rendered negative effects. The activity of the enzyme was inhibited by EDTA and enhanced by $Cu^{2+}$ ions, thus indicating the nature of the enzyme as a metalloprotease. The enzyme showed extreme stability and activity even in the presence of detergents, surfactants, and organic solvents. Moreover, the present findings opened new vistas in the utilization of wheat bran, a cheap, abundantly available, and effective waste as a substrate for SSF.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.205.1-205.1
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• 2010

국내에서 발생하는 생활폐기물 발열량이 최근 3,000 kcal/kg 정도를 웃돌고 있고 사업장 폐기물의 경우는 4,000~7,000 kcal/kg 정도로 높아 이러한 가연성 폐기물 들은 자원화하여 에너지원으로 사용가능하다. 폐기물 자원화 기술의 하나인 가스화 기술을 적용하면 폐기물 내의 가연분은 CO, $H_2$가 주성분인 합성가스로 전환되어 화학원료 또는 발전원료로서 활용이 가능하다. 본 연구에서는 합성가스의 다양한 활용분야 중에서도 메탄올과 CO의 합성을 통해 얻어지는 초산제조 공정에서 폐기물의 가스화를 통해 발생되는 합성가스 내의 CO를 적용하여 기존 초산제조공정에서 필요한 CO를 생산하기 위해 소모되는 고가의 납사 원료를 절감하고자 하는 방안이 검토되고 있다. 초산은 CO와 메탄올($CH_3OH$)을 금속이온계 귀금속촉매 상에서 메탄올카본닐레이션(Methanol carbonylation)반응으로부터 합성되는 것으로, 초산에스테르, 염료, 안료, 의약품 등의 원료로 사용되는 화학원료이다. 일반적으로 초산을 제조하기 위해 사용되는 CO를 생산하기 위하여 납사(Naptha)를 가스화하는 부분산화공정을 이용하거나 촉매를 사용한 Steam reforming공정을 적용하고 있는데, 가스화 및 Steam reforming의 원료가 되는 납사가 고가이고, 원유가가 상승하면 납사의 가격도 상승할 수 있고, 결국 초산제조 비용의 상승을 초래할 수 있다. 폐기물의 가스화를 통해 발생하는 합성가스 내의 CO를 활용하여 초산제조의 원료로 사용할 수 있다면 초산제조 공정에서의 CO 제조 비용 절감 및 폐기물 자원화의 효과를 동시에 달성할 수 있을 것으로 생각된다. 본 연구에서는 초산제조의 원료로 폐기물의 가스화를 통해 발생한 합성가스 내의 CO를 적용가능성을 검토하기 위하여 사업장 폐기물 및 사업장폐기물과 폐유, 건조슬러지 등을 혼합한 복합폐기물의 가스화를 통해 CO의 발생 특성을 분석하였다.

• Journal of Soil and Groundwater Environment
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• v.24 no.6
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• pp.16-25
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• 2019

Anthropogenic polycyclic aromatic hydrocarbons (PAHs) are formed by the incomplete combustion of fuels and industrial waste. PAHs can be widely exposed to the environment (water, soil and groundwater). PAHs are potentially toxic, mutagenic and/or carcinogenic. Fundamental studies such as biota uptake (e.g., earthworm and plant) of PAHs are highly needed. It is necessary to develop alternative ways to evaluate bioavailability of PAHs instead of using living organisms because it is time-consuming, difficult to apply in the field, and also exaction method is tedious and time-consuming. In this study, sorption behaviors of phenanthrene were evaluated to predict the fate of PAHs in soils. Moreover, bioaccumulation of PAHs in an artificially contaminated soil was evaluated using pea plant (Pisum sativum) as a bioindicator. A novel passive sampler, organic-diffusive gradient in thin-film (o-DGT) for PAHs was newly synthesized, tested as a biomimic surrogate and compared with plant accumulation. Sorption partitioning coefficient (K_P) and sorption capacity (K_F) were in the order of natural soil > loess corresponding to the increase in organic carbon content (f_oc). Biota-to-soil accumulation factor (BSAF) and DGT-to-soil accumulation factor (DSAF) were evaluated. o-DGT uptake was linearly correlated with pea plant uptake of phenanthrene in contaminated soil (R²=0.863). The Tenax TA based o-DGT as a biomimic surrogate can be used for the prediction of pea plant uptake of phenanthrene in contaminated soil.

• Journal of Environmental Science International
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• v.6 no.2
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• pp.173-182
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• 1997

The bacterial strains, which utilizes 2,4,4'-trichloro-2'-hydroxydiphenyl ether(TCHDPE) as a sole carbon source, were isolated by selective enrichment culture from soil samples of industrial waste deposits. The bacterium that showed the highestt biodegradation activity was designated as EL-O47R The isolated strain EL-O47R was Identified as the genus Pseudomonas from the results of morphological, cultural, and biochemical tests. The optimum conditions of medium for the growth and the degradation of TCHDPE were TCHDPE 500 ppm, (NH4)2SO4 0.1% as the nitrogen source, initial pH 7.0±0.1, and 37℃, respectively. In this conditions, the regradation rate of TCHDPE was about 97%. Pseudomonas sp. EL-O47R was tested for resistance to several metal compounds and antibiotics. Pseudomonas sp. EL-O47R was moderately grown to Cd(NO3)2, ZnCl2, AgSO4, CuSO4 and HgCl2. This strain was sensitive to rifampicin and kanamycln but resistant to ampicillin, penicillin, tetracyclin and chloramphenlcol. Pseudomonas sp. EL-O47R was grown structurally related com- pounds and potential metabolites of TCHDPE, and has the stability on TCHDPE biodegradation.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.2
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• pp.225-237
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• 2011

For each local town (6 cities and 8 counties) affiliated with Jeonbuk provincial government, characteristics of greenhouse gas (GHG) emissions were analyzed and key emission areas were drawn to establish mitigation policies of the regional greenhouse gases. National Institute of Environmental Research (NIER) reported that the total greenhouse gas emission of Jeonbuk was 20.93 million $tCO_2e$ in 2006. The inland area of 5 cities and 1 county (Jeonju, Gunsan, Iksan, Jungeup, Kimje, Wanju) covered 82% of total greenhouse gas emission in Jeonbuk, while the rest local towns of the province, mostly from mountainous areas were responsible for the rest of the total GHG emission. The cities and counties having relatively higher emission in Jeonbuk province were influenced dominantly by the emission from energy and waste sections. Also, agricultural section showed similar tendency except industrial cities such as Gunsan and Jeonju. In the internal portion of city and county, energy section showed the highest portion at the range of 72.1 (Sunchang)~97.0% (Jeonju) and agricultural section was at the range of 1.2% (Jeonju)~26.6 (Sunchang). When the portion of energy section was higher, the lower agricultural section. The emission index was applied to decide the key city and county and the potential city and county with two methodologies in this study. It was required that the key emission areas were drawn to establish regional greenhouse gases mitigation policies.

• New & Renewable Energy
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• v.7 no.3
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• pp.17-28
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• 2011

Biogas production and utilization are an emerging alternative energy technology. Biogas is produced from the biological breakdown of organic matter through anaerobic digestion. Biogas can be utilized for various energy sectors such as space heating, electricity generation and vehicle fuel. Especially, to be utilized as vehicle fuel, raw biogas needs to be upgraded that is mainly the removal of carbon dioxide to increase the methane content up to more than 95 ~ 97 vol% in some cases, similar to the composition of fossil-based natural gas. Usage of Biogas as a fuel of vehicles have an effect of reducing $CO_2$ emission compared to fossil fuels. Biomethane which is produced by upgrading of biogas is regarded as a good alternative energy and usage of clean energy is encouraged to deal with air pollution and waste management as well as production of clean energy. Recently, biogas projects for vehicle fuel are newly being launched and Korea government have also announced a plan for investment to develop biogas as a transport fuel. In this study, it is aimed to examine the potential feasibility of biomethane as a transport fuel. As a results, the status of biomethane, quality standard, quality characteristics, and upgrading technology of biogas were investigated to evaluate of biogas as a vehicle fuel of transportation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.1
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• pp.127-133
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• 2016

This study is performed that furniture and interior materials of MDF's (Medium Density Fiberboard) biodegradation properties, and the goal of this study is investigation of possibility of waste-MDF's composting after landfilling. To investigate biodegradation, this study was performed according to KS M ISO 14855-1, and there were two different soil conditions including a compost condition and an activated vermiculite condition as artificial soil. This experiment was tested for 40 days. The measurement of carbon-dioxide generation was processed every 24 hour in 1-2 week, and every 48 hour after 3 week. In the same days, MDF showed 24.4% of biodegradation in compost condition, and 6.2% in activated vermiculite. Also, the reference material of TLC (thin-layer chromatography) grade cellulose showed 26.4%, 11.4% in compost and activated vermiculite respectively. The dilution plate method was performed for biological analysis in the study. This experiment was used for investigation of inoculum's (Bacillus licheniformis) activity. As the result of bioassay, compost has more other germs include inoculum than activated vermiculite in the first week. Especially in the 2nd week, the reference material under the compost condition showed the most germ's activity, and also the biodegradation was the highest. Consequentially, compost condition was able to reduce a performing period of biodegradation testing than activated vermiculite. However, activated vermiculite could be stabilizing errors between repetition.

• Journal of Wetlands Research
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• v.15 no.2
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• pp.165-170
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• 2013

Pilot scale study was carried out to produce Volatile Fatty Acids with primary sludge from municipal wastewater treatment plant. An acid fermenter was operated at pH 9, $35^{\circ}C$, SRT of 3.5-4.25d, using a final effluent as elutriating water(Mode-I) and pH 9, SRT 5d, temperature of $35^{\circ}C$(Mode-II), $55^{\circ}C$(Mode-III), using a primarily treated water as elutriating water. Although solubilization rate was enhanced with the increase of temperature, the VFAs production rate was decreased. The VS reduction was shown approximately 56%, and the sludge volume reduction was 93%. The optimal conditions for solubilization was obtained at pH 9, $35^{\circ}C$ and SRT of 5d.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.6
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• pp.701-717
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• 2003

The objective of this study was to extensively estimate the air quality trends of the study area by surveying con-centration trends in months or seasons, after analyzing the mass concentration of PM-10 samples and the inorganic lements, ion, and total carbon in PM-10. Also, the study introduced to apply the PMF (Positive Matrix Factoriza-tion) model that is useful when absence of the source profile. Thus the model was thought to be suitable in Korea that often has few information about pollution sources. After obtaining results from the PMF modeling, the existing sources at the study area were qualitatively identified The PM-10 particles collected on quartz fiber filters by a PM-10 high-vol air sampler for 3 years (Mar. 1999∼Dec.2001) in Kyung Hee University. The 25 chemical species (Al, Mn, Ti, V, Cr, Fe, Ni, Cu, Zn, As, Se, Cd, Ba, Ce, Pb, Si, N $a^{#}$, N $H_4$$^{+}$, $K^{+}$, $Mg^{2+}$, $Ca^{2+}$, C $l^{[-10]}$ , N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$, TC) were analyzed by ICP-AES, IC, and EA after executing proper pre - treatments of each sample filter. The PMF model was intensively applied to estimate the quantitative contribution of air pollution sources based on the chemical information (128 samples and 25 chemical species). Through a case study of the PMF modeling for the PM-10 aerosols. the total of 11 factors were determined. The multiple linear regression analysis between the observed PM-10 mass concentration and the estimated G matrix had been performed following the FPEAK test. Finally the regression analysis provided source profiles (scaled F matrix). So, 11 sources were qualitatively identified, such as secondary aerosol related source, soil related source, waste incineration source, field burning source, fossil fuel combustion source, industry related source, motor vehicle source, oil/coal combustion source, non-ferrous metal source, and aged sea- salt source, respectively.ively.y.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.696-703
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• 1994

To utilize waste of squid effectively, antioxidant properities of squid viscera were elucidated. Major fatty acids of total lipid, neutral lipid and phospholipid were $C_{16:0},\;C_{18:1}\;and\;C_{20:5},\;C_{22:6}$ and consisted $63{\sim}71\%$ of total fatty acids. Total lipid did not show significant antioxidant activity when added to the fish oil at the concentration below $5.0\%$, Antioxidant activity of hexane extract was lower than total lipid or tetra carbon chloride-methanol($CCl_4-MeOH$) extract. Extracts with $CCl_4-MeOH$ exerted higher antioxidant activity as the methanol ratio was increased, suggesting that polar lipid plays and important role.