• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.3
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• pp.117-125
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• 2006

A microorganism capable of degrading toluene was isolated from crude oil contaminated soil and identified as Pseudomonas fluorescence. The effects of environmental factors on the degradation of toluene were investigated. The optimum temperature for toluene degradation was $30^{\circ}C$ and the maximum specific cell growth and toluene degradation rates were $0.76hr^{-1}$ and $0.36hr^{-1}$, respectively. Although the wild cells were not able to degrade toluene at $10^{\circ}C$ and $40^{\circ}C$, the cells adapted to toluene at $30^{\circ}C$ degraded 100mg/L of toluene completely at $10^{\circ}C$ and 80% of the toluene at $40^{\circ}C$. The wild cells were not able to degrade more than 200mg/L of toluene but the toluene-adapted cells degraded up to 300mg/L of toluene. Although the optimum pH was 7.0, the degradation rates were not much different in the range of 5.5 to 9.0. When nitrate was used as a nitrogen source instead of ammonium, the adaptation period became longer by 2~10 hours and the cell growth yield became lower by 45%. The toluene degradation rates after adaptation period, however, were almost same in both cases. The observations in this study will be used in the future biofilter design and operation.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.77-84
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• 2003

Chitinase was purified from an antagonistic bacterium Bacillus sp. 7079 by ammonium sulfate precipitation, QAE-Sephadex anion exchange chromatography, Sephadex G-100 gel filtration, and SP-Sephadex cation exchange chromatography. The molecula. weight of purified chitinase (PC-1) was approximately 66.5 kDa on SDS-PACE. PC-1 exhibited optimum pH and temperature of pH 7.5 and $45^{\circ}C$, respectively. More than $80\%$ of PC-1 was stable at pH 5.0 to 9.0, and more than $90\%$ at $40^{\circ}C$. $Fe^2+\;and\;Ca^2+$ inhibited the chitinase activity about $20\%$, and EDTA and p-CMB by about $30\%$, whereas $Ag^+$ inhibited the activity up to $65\%$. The $K_m$ value of PC-1 was 1.215 mg/ml with colloidal chitin as a substrate. We also investigated the effect of PC-1 treated chitin (PCTC) on the pro-inflammatory cytokine gene expression in macrophage RAW 264.7 cells. The expression of IL-$1{\alpha}$ and IL-$1{\beta}$ mRNA gene was investigated using reverse transcriptase polymerase chain reaction (RT-PCR). IL-$1{\alpha}$ and IL-$1{\beta}$ mRNA were induced by the treatment of PCTC and chitin only in RAW 264.7 cells. These expressions were induced as early as 2 h and sustained up to 24 h in RAW 264.7 cells. IL-$1{\alpha}$ and IL-$1{\beta}$ mRNA were more strongly expressed by the treatment of PCTC than chitin treatment alone in RAW 264.7 cells.

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.40-40
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• 2002

Altered intracellular $Ca^{2＋}$ homeostasis is presumably the primary mechanism of the diastolic impairment in diabetic cardiomyopathy. However, causal relations of numerous environmental changes observed in the diabetic heart have been left unresolved. In the present study, we sought to establish an in vitro model of diabetic cardiomyopathy using H9c2 cardiac myocyte cell line.(omitted)

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.9
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• pp.50-55
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• 1997

In order to improve the electrical performance of ITO/InP solar cells, sulfur passivation technique was employed using (N $H_{4}$)$_{2}$ $S_{x}$ solution. Passivation effects were analyzed by measuring the short circuit current density ( $J_{sc}$ ) of solar cells and photoluminescence (PL) of ITO/InP interfaces. This paper firstly reports the sulfur passivation effects by investigating the correlation between the PL intensity and the short circuit current. Generally, PL intensity and the short circuit current of sulfur passivated sampels wer eincreased, and showed the same trend. Especially, samples prepared at 60.deg. C (N $H_{4}$)$_{2}$ $S_{x}$ solution exhibited the highest $J_{sc}$ and PL intensity. These results demonstrated that the short circuit currents was influenced by the ITO/InP interface states.

• Journal of environmental and Sanitary engineering
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• v.12 no.1
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• pp.85-95
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• 1997

Behavior of Listeria monocytogenes in Skim milk during fermentation by Lactobacillus bulgaricus YI-2 and Streptococcus lactis FYI-1 were determined. Autoclaved skim milk was inoculated with ca. 10$^{3}$ L. monocytogenes (Strain LM91-1 or LM 96-2) cells/ml, and with 5.0, 1.0, 0.5 or 0.1% of a milk culture of either L. bulgaricus TI-2 or S. lactis FYI-1. Skim milk containing ca. 10$^{3}$ L. monocytogenes was incubated at 37 or 42$\circ $C for 15 h with L. bulgaricus YI-2, and at 21 or 30$\circ $C for 15 h with S. lactis FYI-1. Cultured skim milks were stored at 4$\circ $C in the refrigerater. Samples were plated on Oxford Agar with oxford antimicrobic supplement to enumerate L. monocytogenes and on either modified MRS agar to enumerate lactic acid bacteria. L. monocytogenes survived the 15-h fermentation with S. lactis FYI-1 in all combinations of level of inoculum and temperature of incubation, but inhibition of growth ranged from 94 to 100%. When incubated with over the 1.0% of L. bulgaricus, L. monocytogenes inhibited or disappeared in fermented skim milk from 9 h after incubation. Especially, incubation at 42$\circ $C with 5.0% L. bulgaricus YI-2 as inoculum appeared to be the most effective inhibitory combination for strain LM 91-1, causing 100% inhibition in growth based on maximum papulation attained. In most instances of incubated with L. bulgaricus YI-2, growth of the pathogene appeared to be completely inhibited when the pH dropped below 4.38.

• Proceedings of the Korean Society of Toxicology Conference
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• 2005.05a
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• pp.203-203
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• 2005

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.60-60
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• 2001

Human thrombopoietin (hTPO) is a cytokine that plays a central role in megakaryopoiesis by influencing on the development and maturation of megakaryocyte and platelet production. To induce hTPO production in the mammary gland, expression vector was constructed by combining the promoter of bovine beta-casein gene, cDNA of hTPO and neomycine resistance gene for transfection into fibroblasts. Bovine fibroblast cells derived from female ear skin were transfercted with the expression vector using Lipofectamine (Life Technology, NY). Transected cells resistant to G4l8 treatment (600 $\mu\textrm{g}$/$m\ell$) were recovered and colony formation was initiated at 13 days. The colonies with about 1 cm diameter were picked and analysed by PCR. Single transfected cells were individually transferred to enucleated oocytes. After electrofusion, the reconstructed embryos were exposed to calcium ionophore (5uM) for 5 min followed by treatment with 6-DMAP (2.5 mM) for 4h. The nuclear transfer embryos were cultured in CRlaa medium at 38.5C, 5% $CO_2$ for 7 days. Twenty three of 29 (79.3%) colonies were proved to be hTPO transfectants by PCR. The colonies were further passaged and used to produce transgenic embryos using nuclear transfer. Cleavage and developmental rates of reconstructed embryos to the blastocyst stage were 65.1% and 39.4%, respectively Of 22 blastocysts that developed from reconstructed embryos with the transfected cell, 20 embryos (90.9%) were positive for hTPO by using PCR analysis. The results suggest that somatic cell nuclear transfer is efficient for production of transgenic embryos.

• Journal of Photoscience
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• v.9 no.2
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• pp.335-337
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• 2002

Blue light (BL) induces stomatal opening through activation of H$^{+}$ pump, which creates electrical gradient across the plasma membrane for $K^{+}$ uptake into guard cells. The pump is the plasma membrane H$^{+}$ -ATPase and is activated via phosphorylation of the C-terminus with concomitant binding of the 14-3-3 protein. The opening is initiated by the perception of BL through phototropin (phot), which are recently identified as BL receptors in stomatal guard cells. In this study, we provide the biochemical evidence for phots as BL receptors in stomatal guard cells. vfphot was phosphorylated reversibly by BL, and phosphorylation levels of vfphot increased earlier than those of the plasma membrane W-ATPase. BL-dependent phosphorylations of vfphot and H$^{+}$-ATPase showed similar fluence dependency. Staurosporin, an inhibitor of serine/threonine protein kinase, and diphenyleneiodonium chloride (DPI), an inhibitor of flavoprotein, inhibited BL-dependent phosphorylations of vfphot and H$^{+}$ -ATPase. These results indicate that vfphot acts as a BL-receptor mediating stomatal opening.l opening.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1408-1413
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• 2017

The aim of this study was to investigate the antioxidant activities and protective effects of hot water extract from Curcuma longa L. (CLW) on oxidative stress-induced C2C12 myoblasts. Antioxidant activities of CLW were evaluated based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities. Protective effects of CLW on oxidative stress-induced C2C12 myoblasts were determined based on cytotoxicity, $H_2O_2$ protective activity, and intracellular reactive oxygen species (ROS) level. DPPH and ABTS radical scavenging activities represented by $SC_{50}$ were $188.5{\pm}3.0{\mu}g/mL$ and $92.0{\pm}0.9{\mu}g/mL$, respectively. Using C2C12 myoblasts, CLW treatment increased cell viability against oxidative stress-induced cell death. Further, CLW treatment reduced the intracellular ROS level in cells treated with $H_2O_2$. These results suggest that CLW might have the capability to protect oxidative stress-induced C2C12 myoblasts.

• Applied Microscopy
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• v.27 no.2
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• pp.155-163
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• 1997

Ultrastructural and histochemical studies were carried out on the prostate gland of a Korean slug (Incilaria fruhstorferi) with light and electron microscopes. The results are as follows. The endothelial tissue of the prostate gland is constituted with tall and narrow ciliated columnar cells, irregularly shaped cells and gland cells in which are included the elongated oval or ellipsoid nucleus those are surrounded by curved membrane. The endothelial tissue of the prostate gland is composed by type-A, B, C and type-D gland cells, and the glanules of type-A, B, and D gland cells are certified to neutral mucopolysaccharide because are related by PAS-alcian blue (pH 2.5) , but the other hand type-C gland cell is only weakly reacted to PAS, but strongly reacted by Million reaction. The glanules of type-A gland cell are small size (about $0.4{\mu}m$) and are seen high electron density, but the glanules of type-B gland cell are large size (about $0.7{\mu}m$) and glanule density is same type-A glanules. Long ellipsoid type-C gland cell contained round nucleus which is well developed beterochromatin in, and that small oval glanules (size, about $0.9{\mu}m$) of moderate high electron density which are formed a group of large glanule together with $4\sim5ea$, but type-D gland cell possessed round small nucleus are seen high electron dense glanules (size, $0.8{\mu}m$).