• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.18-24
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• 2005

Water quality changes of wastewater effluent in the shallow aquifier condition was investigated using laboratory unsaturated and saturated SAT columns for over five months. Average DOC removal was 31.9% in the unsaturated SAT column whereas no removal occurred in the saturated SAT column. Under the shallow aquifer condition, nitrification was not completed in the unsaturated SAT column, releasing residual ammonium nitrogen into the saturated SAT column. Short retention time (one day) in the shallow unsaturated SAT column rendered DO of about 2 mg/L to the influent of the saturated SAT column. Phosphate was not removed at all in the unsaturated SAT column while complete removal was achieved in the saturated column. Consequently, organic and inorganic compounds were removed under the shallow aquifer condition as effectively as was in deep aquifer, except for the release of ammonium and relatively high DO into the saturated SAT column.

• Journal of Biomedical Engineering Research
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• v.16 no.3
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• pp.331-336
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• 1995

A composite material was produced as an artificial bone substitute which is gradually degrAded and replaced by the regenerated natural bones after implantation. To detect the effect of the material on the cell's activity, the composite specimens were placed in MEMs and incubated at $37^{\circ}C$ for one week. Human uterus cervical cancer origin HeLa 3 cells and mouse subcutaneous origin L929 cells were cul- tured in the specimen dissolved MEMs for 5 days to investigate cytotoxicity via cell growth rates. ${Na_2}^{51}CrO_4$ solution was added to the media, to label the HeLa 53 cells, and the released amount of $^{51}Cr$ was measured by a $\gamma$-counter. On the cell growth investigation, no significant cytotoxic phenomena were revealed in both HeLa S3 and L929 cell cultures. On the released 51CR from the incubated HeLa 53 cells, no significant cell degeneration was observed from the composite embedded MEMs.

• Journal of Environmental Science International
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• v.26 no.6
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• pp.691-710
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• 2017

This study was performed to investigate the geochemical and benthic environment of three shellfish farms in Suncheon Bay during the period of September 2014 ~ April 2015. Three sampling stations were selected; St.1 is the shellfish farm of razor clam near Jangsan area. St.2 is the shellfish farm of small ark shell near Hwapo area and St.3 is the shellfish farm of razor clam near Yongdu area. Razor clam was the dominant species at St.1, small ark shell and granulated ark shell were dominant at St.2 and St.3, respectively. Granulated ark shell inhabited St.3, although it is not cultured at that station. This station's exposure to air during the ebb tide and sediment composition likely provides the appropriate habitat for granulated ark shell species. Analysis of the number of different species showed that 8 benthos species were found to be distributed at St.1, 18 species at St.2, and 13 species at St.3. Among three stations, the highest Ignition Loss (IL), Chemical Oxygen Demand (COD) and Acid Volatile Sulfide (AVS) values were obtained from the sediment at St.2. The analysis of pore water from St.2 also showed the highest values of Total Organic Carbon (TOC), ammonia ($NH_4^+$), Dissolved Inorganic Nitrogen (DIN) and phosphate ($PO_4^{3-}$). These results are related to the fact that species dominance and richness is the highest in St.2.

• KSBB Journal
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• v.15 no.3
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• pp.285-292
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• 2000

Support media for yeast immobilization was prepared from a porous volcanic rock used as a moisturizer in orchid growing. The rock was broken to the size of 2-3 mm and burned at $600^{\circ}C$ in a furnace in order to remove organic materials blocking the pores or treated with HCI solution or NaOH solution to remove the inorganic dirts by dissolving. Even through both the acid and the akali solution were effective the latter was not recommendable because it broke the pore structure by dissolving the elements of the media. This media was mainly consisted of SiO2 with $Al_2O_3$ as a minor component and CaO and K2O as trace elements. It had the finely developed pores of $15-80\mu\textrm{m}$size. Yeast immobilization capacity of this media was about $5{\times108}$ cells/ml bed which is large enough to be used for the practical applications. Yeast immobilization capacities of Alumina and Cordierite were much smaller than that of silica-based media. Scanning electron micrograph of Cordierite and Alumina showed uneven surfaces and small size of pores in contrast to relatively smooth surface and large pores of silica based media which means that smooth surface and large pores are desirable for the good adsorption of microbes on the media.

• Economic and Environmental Geology
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• v.36 no.3
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• pp.171-176
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• 2003

The fate and behavior of polycyclic aromatic hydrocarbons(PAHs) and heavy metals in the environment are mainly controlled by their interactions with various components of soils and sediments. Due to their large surface area and abundance in many soils, smectites may greatly influence the fate and transport of the contaminants. In our experiment, PAH sorption by hexadecyltimethylammonium(HDTMA)-modified smectite linearly increased in proportion to the amount of HDTMA added on the clay. However, trimethylammonium(TMA)-modified smectite did not show superiority in its sorption of PAH compared with the HDTMA-smectite or dodecyltrimethylammonium(DTMA)- smectite. Meanwhile, the smectites modified with the same cationic surfactants adsorbed Cd$^{2＋}$(heavy metal) significantly from water at low surfactant loading level, but the Cd$^{2＋}$ adsorption linearly decreased as the loading of surfactant increased. The result shows that the sorption tendency of organoclays for organic or inorganic contaminants was significantly influenced by the amount and size of the surfactants added on the clay. This reveals that the stabilization and configuration of cationic surfactant formed on the clay interlayer of different sizes may be an important factor in controlling the sorptive capacity of each pollutant in the environment.

• Korean Journal of Food Science and Technology
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• v.8 no.1
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• pp.33-41
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• 1976

These experiment were conducted to investigate the cultural condition of the lipase production by Rhizopus japonicus. The results obtained were as follows: 1. Soybean meal and ammonium sulfate were the most effective in the lipase production as organic and inorganic nitrogen sources, respectively. 2. The lipase production was strongly inhibited, when added as carbon sources xylose, glucose, fructose, galactose, maltose, soluble starch, and dextrin causing the lowering of pH of the medium during culture. Sucrose did not inhibit the lipase production, but not caused any effect when added. 3. $K_2HPO_4$ as phosphate salt and $MgSO_4{\cdot}7H_2O$ as magnesium salt were the most effective in the lipase production. 4. The addition of olive oil, soybean oil, and coconut oil respectively increased the enzyme production and especially 1% olive oil increased it by 50%. 5. The enzyme production increased slightly on the addition of yeast extract to $0.05{\sim}0.07%$. 6. The optimum composition of the medium for the lipase production by Rhizopus japonicus was in the composition of soybean meal 2%; $K_2HPO_4{\cdot}$ 0.5%; $(NH_4)_2SO_4$ 0.1%; $MgSO_4\;7H_2O$ 0.05%; yeast extract 0.05%; olive oil 1%. The maximum production of the lipase was attained by the incubation far 48hrs under the optimum incubation condition.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.97-105
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• 1977

1) In order to obtain a microbial strain having a strong yeast cell wall lytic activity, about 156 isolates capable of forming clear zones on baker's yeast-peptone-bouillon agar plate were obtained from soil, mud and water samples and a strain K-42 with the highest lytic activity was identified as Bacillus circulans. 2) Effect of carbon sources on the lytic enzyme production by the K-42 strain was in the decreasing order of maltose>glucan>xylose>control in 2-day culture and of lactose>galactose>glucan>control in 3-day culture. Effect of inorganic nitrogen sources was in the decreasing order of ammonium acetate>sodium nitrate>control in 2-day culture and of ammonium chloride>ammonium oxalate>control in 3-day culture, whereas organic nitrogen sources except milk casein showed an increase in 2-day culture and a decrease in 3-day culture. Synergistic effect of carbon sources and nitrogen sources was not observed. 3) The enzyme production by the K-42 strain was greatly affected by pH change of the culture medium, thus a high lytic activity could be maintained by keeping the pH range of $7{\sim}8$ and adding carbon or nitrogen sources. 4) Optimum conditions for the lytic activity of the K-42 strain were obtained at $pH\;7{\sim}8$ and $60^{\circ}C$ and the extent of hydrolysis toward heated yeast cell wall was 65%.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.583-591
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• 2002

Biodegradation of fat, oil, and grease (FOGs) plays an Important role in wastewater management and water pollution control. However, many industrial food-processing and food restaurants generate FOG-containing waste waters for which there Is no acceptable technology for their pretreatment. To solve these problems, this study evaluated the feasibility of effective FOG-degrading microorganisms on the biodegradation of olive oil and FOG-containing wastewater. Twenty-two strains capable of degrading FOGs were isolated from five FOG-contaminated sites for the evaluation of their FOG degradation capabilities. Among twenty-two strains tested, the lipase-producing Pseudomonas sp. strain D2D3 was selected for actual FOG wastewater treatment. Its biodegradability was performed at 3$0^{\circ}C$ and pH 8. The extent of FOG removal efficiency was varied for each FOG tested, being the highest for olive oil and animal fat (94.5% and 94.4%), and the lowest for safflower oil (62%). The addition of organic nitrogen sources such as yeast extract, soytone, and peptone enhanced the removal efficiency of FOGs, but the addition of the inorganic nitrogen nutrients such as $NH_4$Cl and $(NH_4)_2SO_4$ did not increase. The $KH_2PO_4$ sources in 0.25% to 0.5% concentrations showed more than 90% degradability. As a result, the main pathway for the oxidation of fatty acids results in the removal of two carbon atoms as acetyl-CoA with each reaction sequence: $\beta$-oxidation. Its lipase activity showed 38.5 U/g DCW using the optimal media after 9 h. Real wastewater and FOGs were used for determining the removal efficiency by using Pseudomonas sp. strain D2D3 bioadditive. The degradation by Pseudomonas sp. strain D2D3 was 41% higher than that of the naturally occurring bacteria. This result indicated that the use of isolated Pseudomonas sp. strain D2D3 in a bioaugmentating grease trap or other processes might possibly be sufficient to acclimate biological processes for degrading FOGs.

• Membrane Journal
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• v.19 no.1
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• pp.7-18
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• 2009

In this study, we used the hybrid module that was composed of granular activated carbons (GAC) packing between module inside and outside of tubular ceramic microfiltration membrane for advanced drinking water treatment. Instead of natural organic matters (NOM) and fine inorganic particles in natural water source, modified solution was prepared with humic acid and kaolin. We were investigated effect of water-back-flushing time (BT) and water-back-flushing period (FT) to minimize membrane fouling and to enhance permeate flux (J) in the hybrid process, and tried to find the optimal operating conditions. As a result, resistance of membrane fouling ($R_f$) was slightly decreased according to increasing BT. Also, the shorter FT was the more effective to reduce $R_f$ and to enhance J because of frequent water-back-flushing. However, the optimal BT and FT conditions were 10 sec and 8 min respectively when operating costs were considered. Then, the optimal conditions derived from our experiments of modified solution were applied to lake water treatment. As a result, average treatment efficiencies of turbidity, $UV_{254}$ absorbance, and $COD_{Mn}$ were very high as 99.11%, 91.40% and 89.34%, respectively, but that of TDS was low as 30.05%.

• The Korean Journal of Mycology
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• v.14 no.2
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• pp.131-139
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• 1986

Cultural and nutritional conditions for Lyophyllum decastes and its chemical composition in a synthetic medium were investigated. The optimal temperature and pH for the production of mycelium were $25^{\circ}C$ and pH 7.5. The mycelium yield was the highest on 15th day. Among the carbon sources, glucose and CMC were the best for the production of mycelium and their optimal concentrations were 3 and 6%, respectively. As an organic nitrogen, proteose peptone was the best and $(NH_4)_2HPO_4$ as an inorganic nitrogen was good. The optimal concentration of proteose peptone and $(NH_4)_2HPO_4$ were 2 and 0.2%, respectively. The optimal ratio of glucose to proteose peptone for production of mycelium was 10 : 1. Also, the optimal concentrations of $K_2HPO_4$ and $MgSO_4$ were 0.2 and 0.06%, respectively and that of $CaCl_2$ was 0.1%. Among the bioextracts, yeast extract was the most effective and its optimal concentration was 1.5%. In chemical components of the mycelium of Lyophyllum decastes, total sugar, crude protein and crude fat were 34.80, 28.35 and 2.50%, respectively. Its ash was 7.57% and crude fiber 11.99%.