• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.694-700
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• 2018

To investigate the effect of heavy metals (Cu, Cd, Hg, Pb, Zn) on mosquito Culex pipiens, 50% lethal concentration ($LC_{50}$) concentration, total lipid content, lipid content composition, and total protein content were measured. The results showed that the Hg $LC_{50}$ was $0.45mg\;kg^{-1}$ and the Hg toxicity was higher than the other metals. The results also showed that cadmium (Cd) significantly retarded the growth of mosquito larvae among the tested heavy metals. Six types of lipid bands were isolated from mosquito samples exposed to heavy metals, and five of them were identified (phospholipid, cholesterol, fatty acid, triglyceride, and cholesterol ester). The total lipid content of all treatments decreased compared to the control. In addition, the protein content of the control group ($0.51mg\;ind.^{-1}$) was higher than that of the treated group, and the protein content of the larvae treated with Hg and Cd was very low. In conclusion, heavy metals not only lower the survival rate of mosquitoes, but also affect the protein content and lipids in the mosquito's body, thereby causing growth inhibition. These results indicate that heavy metal contamination will affect the size of mosquito population by inhibiting the survival and growth of mosquitoes, and it is expected that it can be used to measure the degree of contamination using mosquito through subsequent studies.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.94-99
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• 2004

The activities of enzymes that act on oxygen derivatives in Rhodobacter sphaeroides D-230 were investigated under various culture conditions. Intracellular SOD activity from the cells grown in aerobic or anaerobic culture conditions was highest at pH 7.0 and pH 8.0, respectively. On the other hand, extracellular SOD activity was highest at pH 6.0. Catalase activity was highest at neutral pH in both cases. Growth of R. sphaeroides D-230 in aerobic or anaerobic culture conditions was inhibited by methyl viologen. As R. sphaeroides D-230 was cul-tured aerobically, SOD activity was increased about 2-fold by addition of iron ion. But $Mn^+2$ had little effect on the SOD activity of R. sphaeroides D-230 grown in aerobically. NaCN, the inhibitor of Cu$.$Zn-SOD, did not inhibit SOD activity. But, $NaN_3$, the inhibitor of Mn-SOD, inhibited SOD activity in anaerobic cultures con-dition. Therefore, R. sphaeroides D-230 produce Mn-SOD in anaerobic condition, although Fe-Sod is produced in aerobic condition. The activity of catalase was induced by methyl viologen, however, extremely inhibited by NaCN and $NaN_3$.

• Korean Journal of Microbiology
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• v.40 no.1
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• pp.29-36
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• 2004

The purpose of this work was to investigate the relationships between acrylamide degradation by Pseudomonas sp. JK-7 and several relevant physicochemical environment parameters. In initial experiments, the bacterial culture, strain JK-7 isolated from paddy soil sample was developed to grow aerobically with acrylamide as the sole source of carbon and nitrogen. The bacterium was identified as genus Pseudomonas in the basis of use BIOLOG test, and designated as Pseudomunas sp. JK-7. Strain JK-7 could degrade 50 mM acrylamide completely within 72 hours of incubation. Major intermediates resulting from acrylamide degradation were not detected with the HPLC methodology except acrylic acid which appeared to accumulate transiently in the growth medium. The pH increased from 7.0 to 8.7 with complete degradation of the initial 50 mM acrylamide within 72 hours of incubation. pH control in the range of 5 to 9 influenced the growth of JK-7 and acrylamide degradation, whereas it was not examined the growth and degradation at pH 3 or pH 11, respectively. The effect of supplemented carbons (e.g., glucose, fructose, citrate, succinate) on the acrylamide degradation by the test culture of JK-7 was evaluated. The results indicated that the addition of carbons accelerated the bacterial growth and acrylamide degradation compared to those in the absence of supplemented carbons. The effect of supplemented nitrogens on the degradation was monitored. Increasing concentrations of yeast extract resulted in higher growth yield, based on the turbidity measurement, and complete degradation of acrylamide. However, acrylamide degradation was essentially uninfluenced by the addition of $(NH_{4})_{2}SO_{4}$, $NH_4Cl$ or urea. Addition of $AgNO_3$, $CuSO_4$ or $HgCl_2$ except $ZnSO_4$ in the test culture inhibited the degradation of acrylamide and growth of JK-7.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.663-669
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• 2008

The solvent-tolerant bacterium Enterobacter sp. VKGH12 is capable of utilizing n-butanol and contains an $NAD^+$-dependent n-butanol dehydrogenase (BDH). The BDH from n-butanol-grown Enterobacter sp. was purified from a cell-free extract (soluble fraction) to near homogeneity using a 3-step procedure. The BDH was purified 15.37-fold with a recovery of only 10.51, and the molecular mass estimated to be 38 kDa. The apparent Michaelis-Menten constant ($K_m$) for the BDH was found to be 4 mM with respect to n-butanol. The BDH also had a broad range of substrate specificity, including primary alcohols, secondary alcohols, and aromatic alcohols, and exhibited an optimal activity at pH 9.0 and $40^{\circ}C$. Among the metal ions studied, $Mg^{2+}$ and $Mn^{2+}$ had no effect, whereas $Cu^{2+},\;Zn^{2+}$, and $Fe^{2+}$ at 1 mM completely inhibited the BDH activity. The BDH activity was not inhibited by PMSF, suggesting that serine is not involved in the catalytic site. The known metal ion chelator EDTA had no effect on the BDH activity. Thus, in addition to its physiological significance, some features of the enzyme, such as its activity at an alkaline pH and broad range of substrate specificity, including primary and secondary alcohols, are attractive for application to the enzymatic conversion of alcohols.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.87-92
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• 2000

This study was designed to investigate the effects og $10{\%},\;20{\%}\;and\;40{\%}$-addition of functional brown algae (FBA)-noodles on oxygen radicals and their scavenger enzymes in liver of Sprague-Dawley(SD) male rats. Hydroxyl radicals$({\cdot}OH)$ formations were significantly inhibited$(20{\~}35{\%}\;and\;12{\~}20{\%})$ in liver mitochondria and microsomes of rats administered $0{\%},\;20{\%}\;and\;40{\%}$ FBA-noodles compared with that of control group. Significant differences in $H_2O_2$ formations of liver microsome in these FBA-noodles fed groups could not be obtained, but superoxide-radical $(O_2^({\cdot}-))$ formations of liver cytosol resulted in a significant decrease about $10{\%}\;in\;20{\%}\;and\;40{\%}$ FBA-noodles compared with control group. Mn-SOD activities in liver mitochondria were significanlty increased $(10{\~}15{\%})$ in the groups fed $10{\%},\;20{\%}\;and\;40{\%}$ FBA-noodles, while a group administered $40{\%}$ FBA-noodle only resulted In a significant increases $(about 12{\%})$ in Mn-SOD activity of liver microsomes compared with control group. Cu, Zn-SOD activities in liver cytosol were significantly increased $(10{\~}20{\%})\;in\;10{\%},\;20{\%}\;and\;40{\%}$ FEA-noodles compared with control group. Administration of $10{\%},\;20{\%}\;and\;40{\%}$ FBA-noodles resulted in a marked increases$(20{\~}40{\%})$ in liver cytosolic glutathione peroxidase (GSHPx) compared with control group. Significant differences in lipid peroxide (LPO) levels of mitochondria and microsomes in $10{\%}$ FBA-noodle could not be obtained, while LPO levels of $20{\%} and 40{\%}$ FBA-noodles were significantly inhibited about $10{\%}$ in mitochondria and microsomes compared with control group. These results suggest that these FBA-noodles may play a desirable role in attenuating an oxygen radical formations and increasing a scavenger enzymes activity by some brown algae (Undaria pinnatifida) components.

• Journal of Environmental Science International
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• v.22 no.7
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• pp.787-799
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• 2013

The aim of this study was to investigate the accumulation of metallic elements and the control effect of marine pollution caused by ocean dumping in the sediments at a waste disposal area in the Yellow Sea. In July 2009, concentrations of organic matter and metallic elements (Al, Fe, As, Cd, Cr, Co, Hg, Ni, Mn, Pb, and Zn) were measured in surface sediments at the site. The ignition loss (IL) in the surface sediments showed a mean value of 15.4%, about 1.5 times higher than the mean value of the sediments in the coastal areas of Korea. The chemical oxygen demand (COD) at some disposal sites exceeded 20 mg $O_2/g{\cdot}dry$, which signifies the initial concentration of marine sediment pollutants in Japan. The disposal sites contain higher concentrations of Cr, Cu and Zn than the sediments of bays and estuaries that might be contaminated. The magnitude of both metal enrichment factors (EF) and adverse biological effects suggest that pollution with Cr and Ni occurred due to the dumping of waste in the study area. In addition, the geoaccumulation index (Igeo) showed that the surface sediments were moderately contaminated. By the mid-2000s, when the amount of waste dumped at this site was the highest, the concentration of metallic elements was higher than ever recorded. On the other hand, in 2008-09, the need for environmental management was relatively low compare with the peak. As a result, the quality of marine sediment has been enhanced, considering the effect of waste reduction and natural dilution in the disposal area.

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.367-375
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• 2011

This study was carried out to investigate the effects of the level of cracked whole barley on daily feed intake, daily body weight gain, carcass characteristics and meat composition of finishing Hanwoo steers (feeding from 24 months to 30 months of age). The dietary treatments were consisted of five types (C; normal concentrate as a basal diet, T1; 10% addition of cracked whole barley, T2; 20% addition of cracked whole barley, T3; 30% addition of cracked whole barley, T4; 40% addition of cracked whole barley). A total 30 Hanwoo steers (588.6${\pm}$11.8kg) were allocated to 5 feeding groups. The daily feed intake and daily body weight gain were high in the order of T2 > T3 >T4 > T1 > C. The back fat thickness and longissmus muscle area were highest in C and T1, respectively (P<0.05) than other treatments. The meat yield index decreased with increased back fat thickness. The marbling score and meat quality were highest in T1 (P<0.01, 0.05, respectively), but maturity, fat color and meat color were not significantly different among treatments. The crude fat was highest in T1 (17.59%), while in T4 (7.47%) it was lowest (P<0.05). The crude protein and crude ash were not significantly different among treatments. The energy value of cracked whole barley treatments (T1, T2, T3, T4) was higher than C (P<0.05). The contents of Ca, Cu, K, Mg, Mo, Na and Zn were higher in C than the other treatments (P<0.01), but Co was higher in T2 (P<0.01). The CIE $L^*$ value of whole cracked barley treatments (T1, T2, T3, T4) was higher than C, however there were not differences among the treatments. The CIE $a^*$ value was highest in T1(P<0.05) than others. The CIE $b^*$ value was highest in C and it was decreased with increased feeding of cracked whole barley. Based on the above results, T1 treatment compared to other treatments improved the carcass quality parameters like loin muscle area, marbling score, meat quality, and CIE $L^*$ value.

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.816-822
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• 2005

Catharsius protease-2 (CPM-2) was isolated from the body of dung beetles, Catharsius molossus, using a three step purification process (ammonium sulfate fractionation, gel filtration on Bio-Gel P-60, and affinity chromatography on DEAE Affi-Gel blue). The purified CPM-2, having a molecular weight of 24 kDa, was assessed homogeneously by SDS-polyacrylamide gel electrophoresis. The N-terminal amino acid sequence of CPM-2 was composed of X Val Gin Asp Phe Val Glu Glu lie Leu. CPM-2 was inactivated by $Cu^{2+}\;and\;Zn^{2+}$ and strongly inhibited by typical serine proteinase inhibitors such as TLCK, soybean trypsin inhibitor, aprotinin, benzamidine, and ${\alpha}_1$-antitrypsin. However, EDTA, EGTA, cysteine, $\beta$-mercaptoethanol, E64, and elastatinal had little effect on enzyme activity. In addition, antiplasmin and antithrombin III were not sensitive to CPM-2. Based on the results of a fibrinolytic activity test, CPM-2 readily cleaved $A{\alpha}-$ and $B{\beta}$-chains of fibrinogen and fibrin, and y-chain of fibrinogen more slowly. The nonspecific action of the enzyme resulted in extensive hydrolysis, releasing a variety of fibrinopeptides of fibrinogen and fibrin. Polyclonal antibodies of CPM-2 were reactive to the native form of antigen. The ELISA was applied to detect quantities, in nanograms, of the antigen in CPM-2 protein.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.387-396
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• 2012

A study was conducted to determine the dietary effects of Na-bentonite (NaB) and probiotics on meat characteristics and health of Hanwoo steers fed rice straw as a sole roughage source. A total of 24 growing Hanwoo steers (avg BW 232 kg) were assigned to two treatments which included a control diet (concentrate mix and rice straw) and a treatment diet (control diet + 0.5-1.0% NaB + 0.5-1.0% probiotics. The diets were fed for 22 months up to the time the animals were slaughtered. Dietary treatment increased (p<0.05) concentrations of trace minerals such as Zn, Cu, and Fe in the longissimus muscle compared to the control. The treatment diet did not affect cold carcass weight, yield traits such as backfat thickness, longissimus muscle area, yield index, yield grade and quality traits such as marbling score, meat color, fat color, texture, maturity and quality grade. Blood profiles of growing steers were within the normal ranges for healthy cattle. In conclusion, feeding a combination of clay mineral and probiotics to Hanwoo steers fed rice straw as a sole roughage source could have a desirable effect on improving trace mineral retention in longissimus muscle without any deleterious effects on carcass traits of steers.

• Ocean and Polar Research
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• v.25 no.1
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• pp.21-30
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• 2003

Seasonal fluctuations of physico-chemical and biological aspects of the environment were studied in Vladivostok harbour (Golden Horn Bay, the East Sea/Sea of Japan). The benthic community structure was described with a focus on size-spectra (bacteria, meio- and macrofauna) related with the chemical environment and chemical fluxes in sediment and to reveal their possible ecological role in the process of bioremediation of the environment. Samples from two sites with different concentrations of heavy metals (Fe, Zn, Cu, Pb, Mn, Cr, Ni Cd, Co) and petroleum hydrocarbon were assessed by a number of methods. These included plate counts of culturable bacteria, observation through a scanning electron (SEM) and transmission electron microscope (TEM). These approaches were complemented with microscopic assessments of the diversity of the benthic community. The specific communities had a limited number of species, tolerant to abnormally high levels of toxic compounds. The dominant species were presented by several sho.1-lived small polychaetes (Capitella capitata) and nematodes (Oncholaimium ramosum). The highest population density was recorded in microbenthos, in various diatoms, various physiological groups of bacteria which participate in biomineralization: marine heterotrophic bacteria, which oxidized oil, black oil in addition to groups resistant to heavy metals. They have the entire set of mechanisms for neutralizing the negative effect of those compounds, forming the detrital food web and biogeochemical circulation of material in sediments, which results in the biological self-recycling of sea basins. Macro- and meiobenthic organisms were more sensitive to a greater extent of $H_2S$ and petroleum hydrocarbons than to metal content, but the within-site rankings were the same as those achieved for microbiological analyses.