• BMB Reports
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• v.43 no.1
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• pp.23-28
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• 2010

Binary toxin consisting of BinA and BinB from Bacillus sphaericus is toxic to mosquito larvae. BinB is responsible for specific binding to the larval gut cell membrane while BinA is crucial for toxicity. To investigate functional role of cysteine in BinB, three cysteine residues at positions 67, 161, and 241 were replaced by alanine or serine. Mutations at these positions did not affect protein production and overall structure of BinB. These cysteine residues are not involved in disulfide bond formation between BinB molecules. Mosquito-larvicidal assays revealed that C67 and C161 are essential for toxicity, whereas C241 is not. Mutations at C67 and C161 resulted in weaker BinA-BinB interaction. The loss of toxicity may be due to the reduction of interactions between BinA and BinB or BinB and its receptor. C67 and C161 could also play a part during conformational changes or internalization of the binary toxin into the target cell.

• Journal of fish pathology
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• v.15 no.1
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• pp.37-42
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• 2002

Effect of mercury (Hg) toxicity on survival, growth, feed efficiency and oxygen consumption were examined in the juvenile olive flounder. Paralichthys olivaceus. Fishes were exposed to sublethal concentrations of Hg ranging from 0 to 0.13mg/L for 6 weeks. Hg reduced survival rate in a concentration and exposure period-dependent way and suddenly reduction occurred at Hg concentrations greater than 0.05mg/L after 6 weeks. Growth rate and feed efficiency also significantly decreased at greater than 0.028 and 0.05 mg/L respectively. Oxygen consumption rate was significantly decreased to 25 and 32% than that of the control at the Hg concentration of 0.05 and 0.13 mg/L respectively. These results suggest that Hg toxicity inhibit physiological function including growth, feed efficiency and oxygen consumption in the juvenile olive flounder, resulting in survival failure at high concentration.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.205-209
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• 1998

This study was conducted to evaluate the effect of triacetin(TA) treatment during manufacturing carbon dual filter for the adsorption of cigarette smoke components by activated carbons. The measurements were carried out by separation of activated carbon from carbon dual filter, and the specific surface area analyzed. The specific surface area of activated carbon from the domestic cigarette filter and from the foreign cigarette filter by degassing at 9$0^{\circ}C$ was 163$\pm$32$m^2$/g, and 16.6$\pm$1.9$m^2$/g, respectively. Those values were very lower than that of degassing at 35$0^{\circ}C$ (Domestic brand: 952$\pm$30$m^2$/g, and Foreign brand: 847$\pm$73$m^2$/g). By comparing the adsorption capacity of acetone and benzene with and without triacetin treated activated carbon, there was a 20% reduction of adsorption capacity by 5% triacetin treatment. Also, from the cilia toxicity test with carbon dual filter treated 0 % TA and 8 % TA, the cilia survival time was 706$\pm$74sec. and 603$\pm$64sec. for 0% TA and 8% TA, respectively. The delivery rate of vapour phase of cigarette smoke, which consists of main components of cilia toxicity, was higher at 8% TA filter than 0 % TA filter. Our results indicate that the treated TA covered the micro-pore of activated carbon, and then reduced specific surface area, finally, decreased the adsorption of vapour phase from cigarette smoke.

• YAKHAK HOEJI
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• v.42 no.4
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• pp.388-394
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• 1998

The lectin from starfish, Asterina pectinifera, was purified and tested for its potential antitumor activity. It was shown to possess considerable toxicity toward various tumor cell lines. Concentration of Asterina pectinifera lectin (APL) at 4mg/$5{\times}10^5$ cells resulted in 28% death of Ehrlich ascites tumor cell, 40% of L929, 60% of A549, and 52% of HeLa cells after 48 hours incubation. Toxicity of APL to L929, Ehrlich ascites, A549, and HeLa cells revealed a reduction in cell viability of approximately 70% at APL concentration of 8mg/$5{\times}10^5$ cells after 48 hours incubation. Administration of APL ($100{\mu}g/day$ or $300{\mu}g/day$) inhibited the growth of Ehrlich ascites cells in vivo. Mice given only Ehrlich cells survived an average of $15{\pm}1$ (S.E.) days. Mice given Ehrlich cells and $100{\mu}g\;or\;300{\mu}g$ APL had 58% and 67% survival, respectively, after 20 days. These results suggest that APL has antitumor activity.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.227-237
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• 2002

One prominent characteristic of2,3,7,8-tetrachlorodibenzop-dioxin (TCDD) toxicity in rats is a reduction of body weight accompanied by an altered serum lipid profile such as hyperlipidemia. A single administration of TCDD (50 ug/kg) resulted in a decrease of body weight and increase of serum cholesterol in rats. TCDD-induced weight loss and serum cholesterol elevation was reduced in rats administered with water extract (100 mg/kg) or saponin fraction (40 mg/kg) of Panax ginseng C.A.Meyer. In contrast, the administration of Panax quinquefolium did not inhibit the TCDD-induced weight loss and serum cholesterol elevation. Histological examinations of liver and testis revealed the administration of saponin fraction of Panax ginseng attenuated the TCDD-induced hispathologicallesions whereas the administration of saponin fraction of Panax quinquefolium did not. High performance liquid chromatographic analysis demonstrated high percentiles of ginsenoside Rg and ginsenoside $Rh_1$ were evident in saponin fraction of Panax ginseng. Results indicate that the protective effects of Panax ginseng, not Panax quinquefolium, on the TCDD-induced toxicity might be resulted from different compositions of saponins in Panax ginseng.

• Journal of Animal Reproduction and Biotechnology
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• v.37 no.3
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• pp.176-182
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• 2022

Norflurazon is widely used on agricultural lands and has a high potential to pollute water sources. However, its effects on fish have not been fully elucidated. The purpose of our study was to determine whether norflurazon adversely affects the developmental stage of zebrafish, which are frequently used as a model system to evaluate the environmental impact of pollutants. Norflurazon interfered with the hatching of zebrafish embryos and induced several sublethal deformities including body length reduction, increased yolk sac volume, and enlargement of the pericardial region. We further examined the cardiotoxicity of norflurazon in the flk1:eGFP transgenic zebrafish line. The vascular network, mainly in the brain region, was significantly disrupted in norflurazon-exposed zebrafish. In addition, due to the failure of cardiac looping, norflurazon-exposed zebrafish had an abnormal cardiac structure. These developmental abnormalities were related to the apoptotic process triggered by norflurazon. Overall, the present study demonstrated the non-target toxicity of norflurazon by analyzing the hazardous effects of norflurazon on developing zebrafish.

• Journal of the Korean Society of Safety
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• v.23 no.3
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• pp.30-35
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• 2008

The recent fire incident in an elementary school of Chonan city causes the media focus on the fire safety of residential container buildings. In this study, real fire tests were conducted in this kind of buildings. Combustion products including $O_2$, $CO_2$, CO, $NO_x,$, $SO_x$, HCI, HCN were measured, in order to investigate the hazard-reduction effects of employing gas mask protected with filter during the fire emergency of residential container buildings. According to the test results, whether or not employing the filter showed a sheer difference in the toxicity of the fire-induced gases, and then the importance of wearing a gas mask was evidently demonstrated.

• Journal of Environmental Science International
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• v.11 no.6
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• pp.561-567
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• 2002

This study was investigated to evaluate the effect of the sodium ion and pH on toxicity of dinitrophenol at high concentrations (0.41 to 0.54 mM), over a sodium concentration range of 0.1 mM to 107 mM and over a pH range of 5 to 9. The concentration of sodium ions in the activated sludge mixed liquor seemed to have very little effect on dinitrophenol toxicity. However, lack of sodium in the growth media resulted in a reduction of the dinitrophenol degradation rate by bacterial isolate from the activated sludge culture, which has been identified as Nocardia asteroides. Dinitrophenol inhibition was found to be strongly dependent on mixed liquor pH. The dinitrophenol degradation rate was highest in the pH range of 6.95 to 7.84; at pH 5.94 degradation of 75 mg/L dinitrophenol was significantly inhibited; at pH < 5.77, dinitrophenol degradation was completely inhibited after approximately 30% of the dinitrophenol was degraded.

• The Journal of Korean Medicine
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• v.24 no.1
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• pp.190-201
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• 2003

Object : This study was designed to investigate the effects of Chungganhaeju-tang (Qingganjiejiu-tang) on cytotoxicity, growth inhibition, apoptosis and expression of cytokine in damaged HepG2 cells. Method : Toxicity on HepG2 cell induced by ethanol and acetaldehyde was measured for viability, cell growth, DNA replication and generation of apoptosis and cytokine. The recovery of the cell activity by Chungganhaeju-tang was estimated for the measured parameters using PCR with different cycle numbers, DNA gel-electrophoresis, and densitometric analysis, Results : Chungganhaeju-tang improves the recovery of HepG2 cells damaged by ethanol or acetaldehyde. The suppressed DNA synthesis of the cell damaged by ethanol or acetaldehyde is improved by Chungganhaeju-tang. A liver-protection effect was shown by the reduction of apoptosis and $TNF-{\alpha},{\;}IL-1{\beta}$ expressions that are induced by ethanol or acetaldehyde. Conclusion : The result indicates that Chungganhaeju-tang reduces toxicity induced by ethanol or acetaldehyde and recovers damaged liver function.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.174-177
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• 1998

The effects of surfactants affecting polycyclic Aromatic Hydrocarbon(PAHs) solubility and biodegradation in soil slurry were investigated. The critical micelle concentration(CMC) values of surfactants used in this study were 12.7mg/L(Brij 30), 13.4mg/L(Tween 80), 13.6mg/t(Triton X-100). The solubility of PAH increased as the Hydrophile-Lipophile Balance(HLB) value of surfactant decrease. At surfactant biodegradation and toxicity experiement using respirometer, Brij 30 did not show any toxic effect and substrate inhibition upon the level of 1.5g/L. Also, biodegradation of Brij 30 gave no reduction on the phenanthrene biodegradation rate. When the desorption rate of phenanthrene between sand and clay is compared, lower percentage of phenanthrene was desorbed at clay because of the larger surface aera and higher organic content of clay. At the biodegradation experiments of phenanthrene in soil slurry phase, more than 90% of initial phenanthrene adsorbed onto both sand and clay were biodegraded by phenanthrene- acclimated cultures.