• KSBB Journal
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• v.16 no.3
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• pp.302-306
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• 2001

The possibility of biomaterials prepared from natural polymer as a skin substitute was evaluated by measuring biocompatibility. Biodegradable films were prepared by solution blend method in the weight ratio of chitosan for the purpose of useful biomaterials. These films were inserted in the back of rat and their biodegradability was investigated by the film weight and hematology as a function of time for the biotransformation. The result of rat test showed that medium, high viscosity chitosan induced some suspects of inbiocompatibililty in the tissue by foreign body reaction 48 and 72 hours after implantation. Also, we prepared the official burn ointment which is made by low viscosity chitosan. This burn ointment was covered on the skin wound of artificial burn and their effect of healing was investigated by the evaluation of the naked eye and hematological change as a function of time. The result of rats test showed that burn ointments made from chitosan was effective reduction of inflammation than negative group.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.409-411
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• 2003

A species of facultative photo-organotrophic, purple, non-sulfur bacterium was isolated from the west coast and the south coast 47 area of Korea at 2001 September. Separated 13 samples of changes with red color under $28{\sim}32\;^{\circ}C$, 3000 lux, anaerobe conditions for 7 days cultivated in Basal medium. For a pure isolation from 13 samples it used agar-shake tube method (0.4 % agar) and it separated 5 strains through 13-repetition test. The RAPD(Random Amplified Polymorphic DNA)-PCR result of strains (EGH-9, EGH-13, EGH-23, EGH-24, EGH-30) that EGH-24 and EGH-30 was same strain. For wastewater biodegradation test that 4 isolation strains cultivated in synthesis wastewater in 7 days. EGH-24 was high 63000 mg/L (CODcr) to 43400 mg/L (CODcr). EGH-24 was selected with efficient wast water treated strain. Based on the results obtained from morphology, nutrient requirements, major bacteriochlorophyll content, 165-rDNA phylogenetic analysis, this strain may be identified as a new strain of the genus Rhodobacter and named Rhodobacter sp. EGH-24.

• Journal of Mushroom
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• v.13 no.1
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• pp.63-67
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• 2015

White rot fungi produce lignin-degrading enzymes such as laccase, manganese peroxidase and lignin peroxidase. These extracellular oxidases efficiently degrade recalcitrant synthetic dyestuffs with diverse chemical structures. Here, we examined the activities of lignin-degrading enzymes in Trametes versicolor using triphenyl methane dyes, crystal violet (CV) and malachite green (MG). Both dyes were decolorized by T. versicolor in solid and liquid culture conditions. T. versicolor decolorized MG more quickly than CV in both conditions. Among three ligninolytic enzymes, laccase was most abundantly found in the decolorization processes of CV and MG. However, higher activity of laccase was needed to degrade CV than MG. The much less activity of MnP was also detected. But the increase of MnP activity was well corresponded to the decolorization efficiency of CV, suggesting the involvement of MnP in CV degrading process. However, its role in the degradation process of MG is supposed to be subsidiary to laccase.

• Journal of Life Science
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• v.18 no.10
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• pp.1331-1335
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• 2008

A Klebsiella pneumoniae WL-5 with the capability of decolorizing several recalcitrant dyes was isolated from activated sludge of an effluent treatment plant of a textile and dyeing industry. This strain showed a higher dye decolorization under static condition and color removal was optimal at pH 6-8 and $30-35^{\circ}C$. More than 90% of its color of Congo Red were reduced within 12 hr at $200\;{\mu}M$ dye concentration. Malachite Green, Brilliant Green and Reactive Black-5 lost over 85% of their colors at $10\;{\mu}M$ dye concentration, but the percentage decolorization of Reactive Red-120, Reactive Orange-16, and Crystal Violet were about 46%, 25%, and 13%, respectively. Decolorizations of Congo Red and triphenylmethane dyes, such as Malachite Green, Brilliant Green, and Crystal Violet were mainly due to adsorption to cells, whereas azo dyes, such as Reactive Black-5, Reactive Red-120, and Reactive Orange-16 seemed to be removed by biodegradation through unknown enzymatic processes.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.4
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• pp.265-272
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• 2008

Biodegradable polybutylene succinate(PBS) is an environment friendly plastics for fisheries, because it can mitigate the ghost fishing problem caused by gill-net and trap fisheries. To evaluate photodegradability of PBS monofilament in comparison with polyamide(PA) and polyethylene(PE) monofilament, these 3 types of monofilaments were spun and exposed to ultraviolet light(UV) of weather-ometer for 900 hours, and then their modification, crystal structure, strength, and extensibility were analysed. PBS monofilament did not show any crack and maintained its crystal structure after 900 hour exposure to UV whereas PE monofilament began showing cracks and structure modification after 600 hour exposure. Under UV exposure, the strength and extensibility decreased more rapidly in PBS than in PA and PE. We estimate that gill nets made of PBS monofilament can endure for about 1 year. The breaking strength and elongation decreased linearly with the exposure time for the 3 types of monofilaments. The derived regression equations of the residual tenacity(RT, kg/$mm^2$) and the residual extensibility(RE, %) with the exposure time in year(Y) for each monofilament were; PBS : RT=48.598 - 8.6437Y($R^2=0.93$), RE=28.165 - 7.3233Y($R^2=0.98$), P A : RT=59.771 - 8.6437Y($R^2=0.98$), RE=32.198 - 5.2772Y($R^2=0.92$), P E : RT=60.898 - 5.6528Y($R^2=0.98$), RE=11.887 - 0.7188Y($R^2=0.98$).

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.358-364
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• 1998

New microbial-control agents were prepared with B. thuringiensis strain NT0423 having unique properties which are different with other B. thuringiensis strains belonging to serotype 7[Kor. J. Appl. Entomol. 32: 426-432.]. Three B. thuringiensis formulations designated as BioBact 10%, 20% and 40%, were made with various combinations of adjuvants. These formulations showed good physical properties in wettability, suspensibility, particle size and adherence. In addition the result of SDS-PAGE analysis indicated that $\delta$-endotoxins remain stably in all formulations. Among the tested formulations, two wettable powder formulations, BioBact 20% and 40%, comprising 20% and 40% of B. thuringiensis technical powder showed the effective control against diamondback moth larvae (Plutella xylostella) in laboratory and field tests. Especially, when compared with commercial B. thuringiensis formulations (A and B commercial formulations) in field evaluation, BioBact 20% and 40% formulations showed equal activity up to 80% lethality and a good persistence effect which remain on leaves at least 7 days.

• Archives of Plastic Surgery
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• v.42 no.2
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• pp.186-193
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• 2015

Background Polyurethane coating of breast implants has been shown to reduce capsular contracture in short-term follow-up studies. This 30-year study is the longest examination of the use of polyurethane-coated implants and their correlation with capsular contracture. Methods This study evaluates the senior surgeon's (F.D.P.) experience with the use of polyurethane-coated implants in aesthetic breast augmentation in 382 patients over 30 years. Follow-up evaluations were conducted for six months after surgery. After the six-month follow-up period, 76 patients returned for reoperation. The gross findings, histology, and associated capsular contracture were noted at the time of explantation. Results No patient during the six-month follow-up period demonstrated capsular contracture. For those who underwent reoperation for capsular contracture, Baker II/III contractures were noted nine to 10 years after surgery and Baker IV contractures were noted 12 to 21 years after surgery. None of the explanted implants had macroscopic evidence of polyurethane, which was only found during the first five years after surgery. The microscopic presence of polyurethane was noted in all capsules up to 30 years after the original operation. Conclusions An inverse correlation was found between the amount of polyurethane coating on the implant and the occurrence of capsular contracture. Increasingly severe capsular contracture was associated with a decreased amount of polyurethane coating on the surface of the implants. No contracture occurred in patients whose implants showed incomplete biodegradation of polyurethane, as indicated by the visible presence of polyurethane coating. We recommend research to find a non-toxic, non-biodegradable synthetic material as an alternative to polyurethane.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.66-69
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• 2002

In this work, cost effective venting is considered by comparing flow rates of 5$m\ell$/min, 10$m\ell$/min, and 20$m\ell$/min. Studies were performed on a soil artificially contaminated with diesel oil (the initial TPH(Total Petroleum Hydrocarbon) concentration of 7098mg/kg), and nutrient condition was C:N:P rate of 100:10:1. The soil has a sandy texture with pH of 6.8, 2.16 ~2.38% organic matter, a total porosity of 47~52% and field capacity 16.2~ 17.2%. The column experiments was made of glass column of 60cm length and 10cm I.D. at controlled temperature of 2$0^{\circ}C$($\pm$2.5$^{\circ}C$). The efficiency of continuous flow rate of 5, 10 and 20$m\ell$/min resulted in separately 61.3%, 58.1%, and 55% reduction of initial TPH concentration(7098mg/kg). Hydrocarbon utilizing microbial count and dehydrogenase activity in air flow of 5$m\ell$/min were higher than those of the others. The first order degradation rate of n-alkanes ranging from C10 to C28 was higher than that of pristane and phytane as isoprenoids. The $C_{17}$/pristane and $C_{18}$phytane ratios for monitoring the degree of biodegradation were useful only during the early stages of oil degradation. Degradation contributed from about 89% to 93% of TPH removal. Volatilization loss of diesel oil in contaminated soil was about 7% to 11%, which was significantly small compared to degradation.n.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.122-126
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• 2002

Contaminant transport in porous media is characterized by solving an advection-dispersion equation(ADE). The ADE can cover equilibrium phenomena of interest, which include sorption, decay, and chemical reactions. Among these phenomena, sorption mechanism is described by several types of sorption isotherm. If we assume the sorption isotherm as linear, the solution of ADE can be easily procured. However, if we consider the sorption isotherm as non-linear isotherm like a Dual Reactive Domain Model (DRDM), the resulting differential equation becomes non-linear. In this case, the solution of ADE cannot be easily acquired by an analytic method. In this paper, we present the numerical analysis of ADE using a DRDM. The results reveal that even if sorption data may be fitted well using linear or non-linear isotherm, the characteristics of contaminant transport of the two cases are different from each other. To be concrete, the retardation of linear isotherm has stronger effect than that of the DRDM. As the non-linearity of sorption isotherm increases, the difference of retardation effects of the two cases becomes larger. For a pulse source, the maximum concentration of the linear model is higher than that of the DRDM, but the plume of the DRDM moves faster than that of the linear model. Behaviors of contaminant transport using the DRDM are consistent with common features of a linear model. For instance, biodegradation effect becomes larger as time goes by The faster the seepage velocity is, the faster the plume of contaminant moves. The plume of the contaminant is distributed evenly over overall domain in the event of high dispersion coefficient.

• Journal of Korea Soil Environment Society
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• v.4 no.3
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• pp.25-33
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• 1999

The recent emergence of biofiltration as a cost effective waste-gas control technology has stimulated in European countries and the USA. Biofiltration of soil vapor extraction off-gas from gasoline contaminated site was simulated in lab-scale in this study. A filling material used was a compost. This study was conducted to evaluate biofiltration characteristics of the compost material for gasoline off-gas. TPH elimination capacity at the gas loading rate of about 50g/$\textrm{m}^3$((filling material)/hr was circa 40g/$\textrm{m}^3$((filling material)/hr. Removal rate of xylene was the highest among BTEX. while it was the lowest in case of bezene. The maximum elimination capacity of the compost was about 1.5g/$\textrm{m}^3$((filling material)/hr for benzene. More than 95% of trimethylbenzene and naphtalene were removed below the loading rate of 0.7g/㎥(filling material)/hr. About 80% of total TPH and BTEX were removed by biodegradation.