• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.213-213
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• 2001

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.495-495
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• 2005

• KSBB Journal
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• v.17 no.2
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• pp.115-120
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• 2002

Biofiltration is a bioprocess treating volatile organic compounds (VOCs) in order to convert the VOCs to harmless products. This review on biofiltration is intended to provide an engineering concept such as removal efficiency, maximum load, elimination capacity and so on. Besides, modeling concept of biofilter is also supplied for designing biofilter system. Quantitative data generated in our research group is shown to explain the engineering concept as well as the modeling idea.

• BMB Reports
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• v.47 no.8
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• pp.433-438
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• 2014

Plant sterols have shown potent anti-proliferative effects and apoptosis induction against breast and prostate cancers. However, the effect of sterols against hepatic cancer has not been investigated. In the present study, we assessed whether the stigmasterol isolated from Navicula incerta possesses apoptosis inductive effect in hepatocarcimona (HepG2) cells. According to the results, Stigmasterol has up-regulated the expression of pro-apoptotic gene expressions (Bax, p53) while down-regulating the anti-apoptotic genes (Bcl-2). Probably via mitochondrial apoptosis signaling pathway. With the induction of apoptosis caspase-8, 9 were activated. The DNA damage and increase in apoptotic cell numbers were observed through Hoechst staining, annexin V staining and cell cycle analysis. According to these results, we can suggest that the stigmasterol shows potent apoptosis inductive effects and has the potential to be tested as an anti-cancer therapeutic against liver cancer.

• Advances in nano research
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• v.6 no.1
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• pp.1-19
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• 2018

Iron oxide nanoparticles excite researcher interest in biomedical applications due to their low cost, biocompatibility and superparamagnetism properties. Magnetic iron oxide especially magnetite ($Fe_3O_4$) possessed a superparamagnetic behaviour at certain nanosize which beneficial for drug and gene delivery, diagnosis and imaging. The properties of nanoparticles mainly depend on their synthesis procedure. There has been a massive effort in developing the best synthetic strategies to yield appropriate physico-chemical properties namely co-precipitation, thermal decomposition, microemulsions, hydrothermal and sol-gel. In this review, it is discovered that magnetite nanoparticles are best yielded by co-precipitation method owing to their simplicity and large production. However, its magnetic saturation is within range of 70-80 emu/g which is lower than thermal decomposition and hydrothermal methods (80-90 emu/g) at 100 nm. Dimension wise, less than 100 nm is produced by co-precipitation method at $70^{\circ}C-80^{\circ}C$ while thermal decomposition and hydrothermal methods could produce less than 50 nm but at very high temperature ranging between $200^{\circ}C$ and $300^{\circ}C$. Thus, co-precipitation is the optimum method for pre-compliance magnetite nanoparticles preparation (e.g., 100 nm is fit enough for biomedical applications) since thermal decomposition and hydrothermal required more sophisticated facilities.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.274-277
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• 2001

This research was conducted as a part of continuous development of a bioprocess to treat thiocyanate($SCN^-$) in the leachate from an industrial landfill site. Detailed characteristics of the leachate, physical and chemical, was analyzed in this study. Time to reach equilibrium in $SCN^-$ degradation at different temperature, similar to the annual variation. was investigated for posssible adaptation of the bioprocess in the treatment site. Complete mineralization of $SCN^-$ to ammonia. bicarbonate and sulfate at all temperature range with except $5^{\circ}C$ trial was observed with different time elapsed to reach equilibrium. which shortened as the process of Fill-Draw proceeded. The final metabolites were mainly nitrate and sulfate. No fouling odor was detected and the settling characteristic of the biomass after the treatment was good(i.e., sludge volume index(SVI) ${\le}$80). Using MWT sludge as an inoculum showed better performance with respect to the elapsed time for treatment and sedimentation characteristics than those of using 2BET sludge.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.368-372
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• 2005

Phytoestrogens are non-steroidal compounds found in a variety of plants, which exert estrogenic effects in animals. In this study, the useful compounds of pomegranate as preliminarily research for the developing of natural estrogen supplement were determined. The estrogenic activity of phytoestrogens in the pomegranate was estimated by using the Yeast Estrogen Receptor and E-screen assay. Estrogenic activity of all pomegranate extracts in the Yest Estrogen Receptor assay were not significant difference at all concentration. Whereas peel extracts of Iranian and domestic red pomegranate are significantly enhanced in the E-screen assay. When various pomegranate extracts enzyme and acid hydrolyzed, three aglycones of phytoestrogen, kaempferol, quercetin and catechin were detected. Peel extract of domestic red pomegranste contained more than kaempferol(87.0 mg%), quercetin(172.8 mg%)) and catechin(956.8 mg%) than other extracts. These differences in concentrations of key phytoestrogens among various extracts seemed to be responsible for their differences in estrogenic activities. Among these three compound, kaempferol showed the highest MCF-7 cell enhancing efface.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.3
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• pp.280-283
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• 2005

The adsorption of a model protein bovine serum albumin (BSA) in expanded bed chromatography was undertaken by exploiting a commercially available expanded bed column (20 mm i.d.) from UpFront Chromatography and Streamline DEAE $(\rho=1.2g/cm^3)$ from Amersham Pharmacia Biotechnology. The influence of whole yeast cells on the adsorption capacity of column was explored by employing yeast cells in a concentration ranged of 0 to $15\%(w/v)$. Equilibrium isotherms for adsorption of BSA on Streamline DEAE were correlated by using Langmuir equation. The presence of yeast cells resulted in decreased of BSA binding capacity in both batch binding and expanded bed chromatography. Results indicated that the yeast cells act as competitor for proteins to bind to the sites on adsorbents.

• Journal of Microbiology and Biotechnology
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• v.5 no.2
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• pp.100-104
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• 1995

Production of $poly-{\beta}-hydroxybutyrate$ (PHB) in a strain of Azotobacter chroococcum, a nitrogen-fixing bacteria, was investigated at various levels of nitrogen and oxygen. Feeding nitrogen source increased both cell growth and PHB accumulation. Oxygen supply appeared to be one of the most important operating parameters for PHB production. Both cell growth and PHB accumulation increased with the sufficient supply of air in the fed-batch fermentation of the strain. However, it was also noted that keeping the oxygen level under limited condition was critical to achieve high PHB productivity. A high titer of PHB (52 g/l) with a high cellular content (60%) was obtained after 48 hr of fed-batch operation by controlling the oxygen supply. Dual limitation of nitrogen and oxygen did not further increase the PHB accumulation probably due to the greater demand for reducing power and ATP for nitrogen fixation.

• Journal of Microbiology and Biotechnology
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• v.20 no.1
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• pp.127-131
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• 2010

In this study, Corynebacterium glutamicum and its derived mutants were used to demonstrate the relationship between proline, glutamate, and ornithine. The maximum ornithine production was shown in the culture medium (3,295.0 mg/l) when the cells were cultured with 20 mM proline, and was 15.5 times higher than in the presence of 1 mM proline. However, glutamate, which is known as an intermediate in the process of converting proline to ornithine, did not have any positive effect on ornithine production. This suggests that the conversion of proline to ornithine through glutamate, is not possible in C. glutamicum. Comparative analysis between the wild-type strain, SJC 8043 ($argF^-$, $argR^-$), and SJC 8064 ($argF^-$, $argR^-$, and $ocd^-$), showed that C glutamicum could regulate ornithine production by ornithine cyclodeaminase (Ocd) under proline-supplemented conditions. Therefore, proline directly caused an increase in the endogenous level of ornithine by Ocd, which would be a primary metabolite in the ornithine biosynthesis pathway.