• Applied Biological Chemistry
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• v.50 no.4
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• pp.268-275
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• 2007

Diversity of the mud flat microbial population in Suncheon Bay was investigated by studying extracellular enzyme activities and 16S rDNA sequences. Four culturable bacterial strains with CMCase, xylanase and protease activities were isolated from the wetland and the mud flat. All the strains produced more xylanase activity than CMCase or protease activity, and the properties of the isolate enzymes from the wetland were similar to those from the mud flat. About 2,000 clones were obtained with the 16S rDNA amplified from the metagenomic DNA isolated from the mud samples. Based on the restriction pattern(s), seventeen clones were selected for base sequence analysis. Of the 17 clones, only 35% (6 clones) were found to be cultured strains and 65% (11 clones) to be uncultured strains. The similarities in the base sequences of the clones ranged from 91.0% to 99.9% with an average similarity of 97.3%. The clones could be divided into 7 groups, Proteobacteria (9 clones, 52.9%), Firmicutes (3 clones, 17.6%), Bacteroidetes (1 clone), Flavobacteria (1 clone), Verrucomicrobia (1 clone), Acidobacteria (1 clone), and Chloroflexi (1 clone). Most of the Proteobacteria clones were gamma Proteobacteria associated with oxidation-reduction of sulfur.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.708-718
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• 2020

Offensive odor is recognized as a social environmental problem due to its olfactory effects. Ammonia(NH₃), hydrogen sulfide(H₂S) and benzene(C₆H₆) are produced from various petrochemical plants, public sewage treatment plants, public livestock wastes, and food waste disposal facilities in large quantities. Therefore efficient decomposition of offensive odor is needed. In this study, the removal efficiency of atmospheric-pressure plasma operating at an ambient condition was investigated by evaluating the concentrations at upflow and downflow between the plasma reactor. The decomposition of offensive odor using plasma is based on the mechanism of photochemical oxidation of offensive odor using free radical and ozone(O₃) generated when discharging plasma, which enables the decomposition of offensive odor at ordinary temperature and has the advantage of no secondary pollutants. As a result, all three odor substances were completely decontaminated within 1 minute as soon as discharging the plasma up to 500 W. This result confirms that high concentration odors or mixed odor materials can be reduced using atmospheric-pressure plasma.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.149-156
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• 2005

This study was conducted to elucidate the relationship between the aboveground vegetation structure and fine roots of the topsoil (<15m), and thereafter to obtain the regression models for the estimation of the fine roots of the topsoil using the aboveground vegetation values in the burned forest areas, Korea. The FRT (fine roots of the top soil) as well as the aboveground vegetation structure showed spatial variation in the earlier successional stages after forest fire. The fine roots (<2 mm) of the topsoil in the earlier successional stages than the first 3 year after forest fire showed the range from 3 to 166 g $DM/m^2$. The FRT in the naturally regenerated sites and planted sites after forest fire was closely correlated with the vegetation indices, especially lvc, representing the development status of the aboveground vegetation. The FRT in the terrace seeding work sites after forest fire was closely correlated with year elapsed after terrace seeding work. The FRT in the terrace seeding work sites showed the much higher values because of the vigorous growth of grass species than the other sites. In the naturally regenerated sites, the FRT showed the parabola form according to the increment of aboveground vegetation value (Ivc). Although the aboveground vegetation value (Ivc) showed a tendency to increase logarithmically during the secondary succession after forest fire, the estimated fine roots of the topsoil was depicted the parabola form showing the gradual increment until the first 15 years and slight decrease thereafter. Decrease of FRT in the later successional stage showing the high vegetation value may be caused by increment of the woody species contribution to the vegetation value (Ivc). Our results represented that the aboveground vegetation value (Ivc) can be used to the estimation of the fine roots of the topsoil in burned forest areas.

• Journal of Embryo Transfer
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• v.19 no.3
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• pp.245-255
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• 2004

In recent years, an increasing number of studies on pig in vitro maturation(IVM) and in vitro fertilization(IVF) have been separated. the wide range of new technologies, including that in applied molecular genetics, has increased this interest. the production of viable porcine embryos in vitro is a prerequisites for the successful production of transgenic pigs to date. The efficiency of IVM/IVF techniques in the porcine is lower than that obtained in other species such as cattle and mouse. The several problems are generally thought to be the cause of poor results: the low rate of MPN formation derived from inadequate IVM of oocytes, the high incidence of polyspermy after IVF and cell blocking at 4 cell during embryos culture. For there reasons overcoming, many studies have been conducted to improve in vitro embryo-genic competence of oocytes. In the last several years, many maturation culture media have been evaluated and various exogenous factors such as hormones and grows factors have been tested to improve the efficiency of porcine in vitro system. In the study several antioxidants have been examined to improve in vitro fertilization and development of porcine oocytes. In this study, several antioxidants were examined to determine the effects on the development of oocytes to the cleavage, morula and blastocyst stage when added at the maturation(IVM) or in vitro fertilization(IVF) or in vitro culture(IVC) of porcine embryos. Porcine oocytes were matured, fertilized and embryos were cultured in defind conditioned medium in vitro with or without supplementation with the antioxidents of cysteine, catalase and glutathione. 1. Significant improvement of blastocyst rate (27.2％ versus 15.4％, p<0.05) were achieved when catalase(500U/$m\ell$) were added to TCM-199 medium and morula rate(72.0％ versus 53.9％, p<0.05) were significantly higher when glutathione(1.0mM/$m\ell$) were added to TCM-199 medium than those of control. 2. In mTBM medium for oocytes fertilization, the addition of cysteine, catalase and glutathione had no positive effect on embryonic development. glutathione had no positive effect on embryonic development. In conclusion, this study shows that addition of catalase, gluththione during IVM improved the rate of porcine embryo development.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.869-876
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• 2013

To develop functional products based on black garlic, a black garlic extract (BG) of 7 brix, a gaeddongssuk extract (GS) of 0.7 brix and two types of mixtures (MBS-I, black garlic 7 brix : gaeddongssuk 0.7 brix; MBS-II, black garlic 14 brix : gaeddongssuk 1.4 brix, 93:7, v/v) were supplemented to rats training on a treadmill for 4 weeks. Body weight from the training did not decrease during the experimental period. Serum albumin content significantly increased in the groups fed an experimental diet compared to the control. The BUN content significantly decreased in BG and MBS-II groups compared to the control. AST and ALP activities significantly decreased in the groups fed an experimental diet compared to the control. Serum triglyceride and total cholesterol levels in MBS-I and MBS-II groups significantly decreased compared to the control. Lipid levels in the serum and liver tissue were not significantly different between the MBS-I and MBS-II groups. The lipid peroxide content in the serum and liver tissue was significantly reduced in the groups fed all extracts compared to the control; the serum and liver lipid contents was lowest in the MBS-I and MBS-II groups, respectively. Hepatic catalase activity in the GS and MBS groups increased by 1.8~2.3 times compared to the control. SOD and GSH-px activities significantly increased from treatment with the extracts by 1.3~1.5 times and 1.2~1.7 times, respectively. These results indicate that a mixture of BG and GS extracts has higher biological activity than a single supplementation of BG or GS extract. Therefore, the addition of gaeddongssuk to black garlic (MBS-I and MBS-II) is effective as a defense material against oxidative stress. MBS-I may be especially effective for its biological activities.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.1
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• pp.33-40
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• 2006

The characteristics of the aluminum waste melting and the distribution of the radioactive nuclides have been investigated for the estimation on the volume reduction and the decontamination of the aluminum wastes from the decommissioning of the TRIGA MARK it and III research reactors at the Korea Atomic Energy Research Institute(KAERI). The aluminum wastes were melted with the use of the fluxes such as flux $A:NaCl-KCl-Na_3AlF_6$, flux B:NaCl-NaF-KF, flux $C:CaF_2$, and flux $D:LiF-KCl-BaCl_2$ in the DC graphite arc furnace. For the assessment of the distribution of the radioactive nuclides during the melting of the aluminum, the aluminum materials were contaminated by the surrogate nuclides such as cobalt(Co), cesium(Cs) and strontium(Sr). The fluidity of aluminum melt was increased with the addition of the fluxes, which has slight difference according to the type of fluxes. The formation of the slag during the aluminum melting added the flux type C and D was larger than that with the flux A and B. The rate of the slag formation linearly increased with increasing the flux concentration. The results of the XRD analysis showed that the surrogate nuclide was transferred to the slag, which can be easily separated from the melt and then they combined with aluminum oxide to form a more stable compound. The distribution ratio of cobalt in ingot to that in slag was more than 40% at all types of fluxes. Since vapor pressures of cesium and strontium were higher than those that of the host metals at the melting temperature, their removal efficiency from the ingot phase to the slag and the dust phase was by up to 98%.

• Economic and Environmental Geology
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• v.46 no.6
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• pp.521-533
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• 2013

This study was initiated to evaluate the applicability of Si slag as an adsorbent via investigation of the main properties of Si slag as an adsorbent aw well as characterization of adsorption features between aqueous arsenic and Si slag. The specific surface area of Si slag was measured to be 6.71 $m^2/g$ which seems to be slightly higher than those of other slags, but relatively lower than those of iron (oxyhydr)oxides extensively used for arsenic controlling processes. The point of zero salt effect (PZSE) of Si slag determined by potentiometric titration appeared to be comparatively high (7.3), indicating the Si slag may be favorably used for adsorption of arsenic which predominantly exists as an oxy-anions. The results of adsorption isotherm indicate that regardless of arsenic species, Langmuir-type isotherm is the most suitable to simulate the adsorption of arsenic onto Si slag. With regard to pH-dependence of arsenic adsorption, the adsorption maxima of arsenite was centered at pH 7, and the adsorption was remarkably decreased in the other pH conditions. In the case of arsenate, on the other hand, the adsorption was highest at the lowest pH (4.0) and then gradually decreased with the increase of pH. Based on the results of kinetic experiments, it is likely that the adsorption of arsenite approached equilibrium within 2 hr, but it took about 8 hr for arsenate adsorption to be equilibrated. In addition, the Pseudo second order was evaluated to be most consistent with the empirical data of arsenic adsorption onto Si slag in this study. Under identical conditions, the affinity of arsenate onto Si slag was estimated to be nearly 6 times higher than that of arsenite.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.369-379
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• 1998

Background: Platelet-activating factor(PAF) might play an important role in the development of acute respiratory distress syndrome. Since PAF induced lung injury is similar to changes of acute respiratory distress gyndrome, and abnormalities in surfactant function have been described in acute respiratory distress syndrome, the authors investigated the effects of PAF on the regulation of surfactant protein A, B and C mRNA accumulation Method: The effects of PAF on gene expression of surfactant protein A, B and C in 24 hours after intratracheal injection of PAF in rats. Surfactant protein A, B and C mRNAs were measured by filter hybridization. Results: The accumulation of SP-A mRNA in PAF treated group was significantly decreased by 37.1 % and 41.6%, respectively compared to the control group and the group treated with Lyso-PAF(p<0.025, p<0.01). The accumulation of SP-B mRNA in PAF treated group was decreased by 18.7% and 32.2 %, respectively compared to the control group and the group treated with Lyso-PAF but statistically not significant. The accumulation of SP-C mRNA in PAF treated group was significantly decreased by 30.7% and 38.5%, respectively compared to the control group and the group treated with Lyso-PAF(p<0.l, p<0.01). Conclusion: These findings represent a marked inhibitory effects of platelet-activating factor on surfactant proteins expression in vivo. This supports, in turn, 'platelet-activating factor might be related to pathogenesis of acute respiratory distress syndrome.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1370-1377
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• 2013

Rice is widely grown in Asia and is one of the major dietary staples in the world. Also, rice contains antioxidants which can prevent from oxidative stress related diseases, including cancer, atherosclerosis, and diabetes. Because the rice is consumed cooked, the effect of the cooking process on the antioxidative and antigenotoxic properties of rice is lacking. The aim of this study was to determine the effects of cooking on the antioxidant and antigenotoxic effects of white rice (WR), brown rice (BR), and germinated brown rice (GBR). The antioxidant activities were measured for total phenolic content (TPC), DPPH radical scavenging activity (DPPH RSA), total antioxidant capacity (TRAP), and oxygen radical absorbance capacity (ORAC). The highest TPC was found in uncooked BR (18.4 mg gallic acid equivalent/100 g). After cooking, the TPC of WR significantly increased, while the TPC of BR and GBR were reduced by 47.7% and 36.7%, respectively. The $IC_{50}$ for DPPH RSA was not significantly different in uncooked rice, while the DPPH RSA of WR and GBR decreased after cooking and the DPPH RSA of BR significantly increased. TRAP values in BR and GBR increased after cooking, while the value of WR decreased. The ORAC values of uncooked WR, BR, and GBR were 5.3, 4.3, and $3.9{\mu}M$ trolox equivalent at the concentration of $50{\mu}g/mL$. After cooking, the ORAC value of BR remained unchanged, while the value of GBR increased and the value of WR decreased. The antigenotoxic activities of WR, BR, and GBR were determined by measuring the inhibitory effects of $H_2O_2$-induced DNA damage on human leukocytes using the comet assay. The results showed that all rice tested showed a significant antigenotoxic effect against oxidative stress, except for the cooked white rice. Overall, our results indicate the addition of brown rice and/or germinated brown rice to cooked white rice is a good option for improving the benefits of rice.

• Korean Journal of Poultry Science
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• v.46 no.2
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• pp.117-125
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• 2019

The aim of the study was to investigate the effects of dietary supplementation of zinc (Zn) sources (zinc oxide and Zn-methionine) on performance, organ weights, blood biochemical profiles, and digestive enzymes of the pancreas and small intestine in Korean native chicks (KNC). A total of 144 KNC (n=6) were fed a basal diet (CON, 100 ppm of Zn), a basal diet supplemented with 50 ppm of Zn with ZnO (ZNO), or a basal diet supplemented with 50 ppm of Zn with Zn-methionine (ZMT) for 28 days. There was no significant difference in body weight, gain, feed intake, and feed conversion ratio among the three groups. The relative weights of the liver, spleen, and intestinal mucosa were unaffected by the dietary source of Zn, whereas pancreas weight in the ZNO group decreased (P<0.05) compared with that in the CON and ZMT groups. Blood biochemical components including aspartate aminotransferase, and alanine aminotransferase were unaffected by dietary Zn supplementation. Pancreatic trypsin activity in the ZNO and ZMT groups was significantly (P<0.05) enhanced compared with that in the CON group. However, the activities of ${\alpha}$-amylase and carboxypeptidase A were not altered by dietary Zn supplementation. The activities of maltase and sucrase were unchanged, whereas the activity of leucine aminopeptidase tended (P=0.08) to be increased by dietary Zn supplementation. In conclusion, the supplementation with 50 ppm of ZnO or Zn-methionine resulted in an activation of protein digestive enzymes in the pancreas and small intestine without affecting animal performance in KNC.