• The Journal of the Korean Society for Microbiology
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• v.19 no.1
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• pp.11-24
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• 1984

Shigella remains to be an important enteric pathogen in this country for the present. Moreover, most of the isolates have become multiple resistant to various antibiotics which used to be drugs of choice for shigellosis. This study was made as an attempt to assess the present stage of antibiotic resistance and the incidence and transferability of R factors of Shigella. A total of one hundred and seventeen strains of Shigella isolated from patients in Seoul and provincial area between 1982 and 1983 were tested for their resistant to antimicrobial agents and transmission of R-plasmid. Antibiotic susceptibilities were determined by an agar dilution method. Muller hinton agar were used for the assay of drug resistance and tryptic soy broth were used for propagating medium for conjugation. Shigella isolated found to be one or more antibiotics were considered potential donor of R-plasmid. The following results were obtained. 1. Among 117 strains of Shigella isolated, 111 strains(94.9%) were found to be resistant to one or more drugs tested and 97.3% of these resistant strains were multiply resistant, indicating the multiply resistant strains were more than the single resistant strains. Only six strains were susceptible to all drugs tested. 2. Among 117 strains of Shigella isolated, 107 strains(91.5%) were resistant to Tetracyclin(Tc), 106 strains(90.6%) to Chloramphenicol(Cp) and Streptomycin(Sm), 97 strains(82.9%) to Ampicillin(Ap), 68 strains(58.1%) to Cephaloridine(Cr), 10 strains(8.5%) to Nalidixic acid(Na), 5 strains(4.3%) to Kanamycin(Km) and 2 strains(1.7%) to Rifampicin. No strain was resisfant to Amikacin(Ak) and Gentamicin(Gm). 3. All drug-resistant Shigella strains, except three, were multiply resistant to two or more drugs. Fifty eight strains were resistant to five drugs, followed by 26 strains resistant to dour drugs, 12 strains resistant to three drugs and 11 strains resistant to six drugs. 4. The 73% of multiply drug-resistant Shigella transferred their resistance to E. coli by conjugation and the resistance was considered to be mediated by R-plasmid. Resistance to Nalidixic acid and Rifampicin were not transferred by conjugation to recipient. As for the transferability of resistance to each seperate drug, Ap resistance was transferred with 73.2% frequence and Cm and Tc resistance were transferred with approximately 50-60% frequence whereas Sm and Cr resistance were transferred in 19.1-21.4% The other four drugs resistant failed to transfer their resistance to recipient. 5. As for the incidence and transferability of resistance to each seperate drug, the strains resistant to Tc and Cm were encountered most frequently with the rate of 91-92%, whereas transfer of Tc and Cm were low, 51-52%. The incidence of Sm resistance was very high(90.6%) but transferability of drugs resistance was much lower(25.4%). Though the incidence of Km reristance was much lower(4.3%) transferability of Km resistance was considerably higher(60%). 6. The greater the multiplicity of resistance, the greater was the likelihood that part of all of the resistance markers would be transferable.

• Journal of fish pathology
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• v.1 no.2
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• pp.77-85
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• 1988

In March 1987, a bacterial disease occured among cultured tilapia (Oreochromis niloticus), in the aquarium of Fish Pathology Laboratory of National Fisheries University of Pusan. The diseased fish showed abdominal inflamation of ascites. The causative organisms isolated from the kidney were Gram negative rods. On SS agar colonies developed within 48 hours at $25^{\circ}C$. On the basis of the morphological and biochemical characteristics the organisms were identified as Edwardsiella tarda. They were sensitive to chloramphenicol, ampicilline and oxytetracycline. The pathogenicity was proved positive by intraperitoneal injection. Three kinds of antigen were prepared with E. tarda for the immune response in tilapia : i.e., by inactivating the strain with 0.4% formalin for 24 hrs at $25^{\circ}C$ ultrasonicating it 3 times with 5 watts for 30 seconds each time and filtrating it through millipore filter. The formalin killed antigen showed good efficacy at the injection concentration of over $10^7$ cells per fish of 50g. All the immunized tilapia showed only a little agglutination titer to the three antigens. The highest survival rate was recorded in challenged tilapia immunized with formalin killed cells.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.263-268
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• 2006

Probiotics including Lactobacillus acidophilus, refer to a group of nonpathogenic organisms that protect the human host against gastrointestinal(GI) infections by pathogenic bacteria such as Shiga toxin-producing E. coli(STEC). In the study, the inhibitory effects of STEC ATCC 43894 adhesion by L. acidophilus A4 was investigated on the HT-29 epithelial cells. Specific proteins regulated by cell Iysates of L. acidophilus A4 on STEC ATCC 43894 were also characterized by proteomic analysis. Both cell mass and Iysate of L. acidophilus A4 have exhibited the profound inhibitory activity on the HT-29 cells(about 1.5 log scale reduction). Two-dimensional gel electrophoresis(2-DE) revealed seven proteins that were up-regulated by cell Iysates of L. acidophilus A4 and three proteins that were down-regulated. In addition, three protein spots were only detected in the presence of cell Iysates. These results suggest that inhibitory effects of STEC adhesion by L. acidophilus may be due to the regulation of specific protein of STEC.

• Journal of Life Science
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• v.16 no.6
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• pp.932-937
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• 2006

The effects of cheonggukjang (CK) on the weight gains, serum and hepatic lipids levels were investigated in adult female rats fed the cholesterol diets. Sprague-Dawley strain rats were given four different types of diet for 4 weeks, respectively: a normal diet, a control diet (10% fat + 0.5% cholesterol), a 5% or 10% CK diets (control diet + 5% or 10% CK powder). The body weights, food intake and food efficiency ratios, and the uterine fat pad weights of 5% CK and 10% CK groups were more significantly decreased than those of the control group. The liver cholesterol and triglyceride levels were significantly lower of the 10% CK group than those of the control group. The concentrations of serum triglyceride, total cholesterol, LDL+VLDL-cholesterol, and atherogenic index ratios were significantly decreased in the 10% CK group compared with those in the control group. The HDL-cholesterol/total-cholesterol ratios was significantly increased in the 10% CK group compared with those in the control group. The fecal total lipid excretion of the 5% and 10% CK groups were more increased than those in the control group. These results showed that the 10% cheonggukjang feeding decreased the triglyceride, total cholesterol, LDL+VLDL-cholesterol and atherogenic index ratios in serum as well as the triglyceride and cholesterol in liver, and increased the HDL-cholesterol/total-cholesterol ratio in serum.

• Journal of Life Science
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• v.27 no.5
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• pp.591-599
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• 2017

It is well established that endurance performance is negatively affected by environmental heat stress. Numerous scientific investigations have attempted to improve performance in the heat with pre-cooling and per-cooling for endurance athletes. Some cooling strategies are more logistically challenging than others, and thus are often impractical for use in training or competition. The purpose of this study was to review the literature on the use of cooling interventions in the improvement of performance and recovery from exercise-induced heat stress. We undertook an examination that focused on the effects of pre-cooling and per-cooling on the improvement in endurance performance and the effects of post-exercise cooling on recovery. The benefits for pre-cooling and per-cooling strategies undertaken in the laboratory setting could be employed by athletes who compete in hot environmental conditions to improve performance. Most laboratory studies have shown improvements in endurance performance following pre-cooling and per-cooling, and in recovery following post-cooling. Cooling strategies such as cooling vest, neck cooling collar, menthol and ice slurry are practically relevant to sports field. Cooling interventions that can be applied frequently to reduce thermal strain prior to, during and directly after training appear to be the best effective strategy to improve performance and recovery. Future research is warranted to investigate the effectiveness of practical pre-cooling and per-cooling strategies in competition or field settings.

• KSBB Journal
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• v.14 no.4
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• pp.440-444
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• 1999

For the effecient production of clavulanic acid., a mutant strain Streptomyces clavuligerus KK was selected from Streptomyces clavuligerus ATCC 27064 through mutation with NTG. S. clavuligerus ATCC 27064 produced about 200 mg/L of calvulanic acid when the medium was composed of 1%(W/V) glycerol, 1.5%(W/V) soybean flour, 0.1%(W/V) $KH_2PO_4$, 0.2%(V/V) soybean oil. A selected mutant, S. clavuligerus KK, produced about 1150 mg/L of clavulanic acid in the same medium. After the addition of $MgSO_4$ to the basal medium, S. clavuligerus KK produced about 1550 mg/L of clavulanic acid, with shows about 1.3 times higher than that produced in the basal medium. In order to select the proper bioreactor for the production of clavulanic acid, a batch culture was performed in an airlift, a bubble column and an stirred tank bioreactors. In an airlift bioreactor, about 1350 mg/L of clavulanic acid was produced, in a bubble column bioreactor, about 1550 mg/L, in a stirred tank bioreactor, about 2200 mg/L, respectively. The production of clavulanic acid in stirred tank bioreactor was about 50% higer than that by an airlift and a bubble column bioreactors. According to this result, the stirred tank bioreactor was selected as a proper bioreactor.

• Journal of the Korean GEO-environmental Society
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• v.16 no.12
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• pp.23-35
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• 2015

Nonlinear soil behavior before failure under dynamic loading is often implemented in a numerical analysis code by a mathematical fitting function model with Masing's rule. However, the model may show different behavior with an experimental results obtained from laboratory test in damping ratio corresponding secant shear modulus for a certain shear strain rage. The difference may come from an unique soil characteristics which is unable to implement by using the existing mathematical fitting model. As of now, several fitting models have been suggested to overcome the difference between model and real soil behavior but consequence of the difference in dynamic analysis is not reviewed yet. In this paper, the effect of the difference on site response was examined through nonlinear response history analysis. The analysis was verified and calibrated with well defined dynamic geotechnical centrifuge test. Site response analyses were performed with three mathematical fitting function models and compared with the centrifuge test results in prototype scale. The errors on peak ground acceleration between analysis and experiment getting increased as increasing the intensity of the input motion. In practical point of view, the analysis results of accuracy with the fitting model is not significant in low to mid input motion intensity.

• Journal of Aquaculture
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• v.11 no.4
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• pp.487-493
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• 1998

This study was conducted to investgate the effect of fish meal analogue (FMA) on the growth of Israeli carp, Cyprinus carpio averageing 43g. Leather meal, meat and bone meal, feather meal, squid liver powder, poultry by-product and blood meal were used for ingredient of FMA. Four experimantal diets were formulated to contain 36% crude protein and 15.4 kJ available enery g-1. The percentage of follows ; Diet 1, 100% 3, 60% WFM + 40% FMA (40% FMA) ; Diet 4, 40% WFM + 60% FMA (60% FMA). In this expriment, fingerling Israeli carp averaging 43 g were assigned to each diet treatment. When the experiment was terminated, weigth gain (WG), feed conversion (FC), specific growth rate (SGR) and protein efficiency ratio (PER) were measured respectively. In the experiment, WG, FC, SGR and PER of Diet 2 were not significantly different from those of the control diet (P0.05). And WG, FC and SGR of Diet 3 were not significantly of the control Diet. In Diet 4, WG, FC and PER were not significantly different from those of the control Diet, but SGR was lower than that fo the control Diet. According to the results from this study, it might be possible to replace fish meal protein by FMA up to 60% in fingerling Israeli carp diets.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.96-103
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• 2009

For the control of pathogenic microorganisms, Bacillus spp. were isolated from diseased pepper fruits in Korea. Among them, Bacillus sp. IUB158-03 showed high inhibitory effect on mycelial growth and spore germination of C. gloeosporioides and Botrytis cinerea. The strain was identified as B. amyloliquefaciens IUB158-03 based on its physiological, biochemical characteristics and Microlog analysis. The highest level of antifungal substances by B. amyloliquefaciens IUB158-03 were obtained when the bacterium was cultured in medium containing 2% soluble starch, 3% yeast extract, 0.5% tryptone, 0.5% $NH_4H_2PO_4$, and 1% NaCl (pH 6.0) at $25^{\circ}C$ for 72 hrs. The antifungal substances were purified by butanol extraction, silica gel column chromatography, preparative thin layer chromatography, and high performance liquid chromatography. The purified antifungal substance was confirmed $R_f$ 0.27 by TLC. This substance exhibited antifungal activity against Fusarium solani, Rhizoctonia solani, Botrytis cineria, Alternata alternaria of plant pathogenic fungi and Trichophyton mentagrophytes, Epidermophyton floccosum, Cryptococcus neoformans of human pathogenic fungi.

• Food Science and Preservation
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• v.23 no.6
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• pp.883-889
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• 2016

A new lactic acid bacteria with gluten-degrading activity which was isolated from salted sea foods (traditional Korea fermented food), identified as Weissella confusa (99%) by use of API kit and 16S rRNA sequencing, and designated as W. confusa. When the W. confusa cultured for 48 hours at $30^{\circ}C$ in a MRS medium containing 1% gluten, 45% of gluten was founded to be degraded. W. confusa showed 85% of survival rate at pH 3, and 94% tolerance at 0.1% oxgall, which indicates that W. confusa would survive in stomach of human. Experiments on the thermostability was confirmed that it has a stability of 70% in $50^{\circ}C$. W. confusa inhibited the growth of some pathogen, except for S. aureus. Results in this study suggest that using W. confusa for fermentation of grain flour containing gluten would be desirable to prepare the gluten-free foods needed for those who suffer from celia disease and gluten allergy.