• 대한미생물학회지
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• 제21권1호
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• pp.33-45
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• 1986

On hundred and forty stains of shigella cultures isolated from the twelve hygiene laboratories of cities and provincial general hospital laboratories in 1983 were tested for their resistance to thirteen antimicrobial drugs and their R-plasmid transfer. Antimicrobial drugs were used amikacin, ampicillin, cephalothin, chloramphenicol, gentamicin, kanamycin, nalidixic acid, rifampicin, streptamycin, tetracycline, tobramycin, cefoperazone and piperacillin. All strains were resistant to one or more of thirteen antimicrobial drugs but 94.3% were susceptible to amikacin, gentamicin and tobramycin of total isolated. The most strains commonly found resistance was to chloramphenicol (94%) followed by streptamycin (93%), tetracyline (92%) piperacillin (90%) ampicillin (83%), cefoperazone (42%), nalidixic acid (14%), cephalothin (17%), rifampicin (22%) and kanamycin (6%), sixty percent of strains among 140 were resistance to ampicillin, chloramphenicol, streptomycin, tetracycline at the same time. The transfer of drug resistance by conjugation was tested and ninety four strains (94.3%) were resistant to one or more drugs were found to transfer their drug resistance of E. coli. percentage of transfer frequency by conjugation was one strains (54%), the transfer frequency of drug resistance varied by donor strains and recipients, but not by selecting drugs. Resistance to nalidixic acid was not transferred by conjugation to recipients. Percentage of plasmid curing after the treatment of acriflavine, acridine orange was about 8%. Among strains cured two strains were tested compare original strains with them in biochemical properties in arginine dihydrolase and arabinose fermentation reaction. It was found to growth curves of No.2 shigella flexneri, serotype 1b, and its derivatives cured with acriflavine in $M{\ddot{u}}ller$ Hinton broth medium (pH 7.4, $38^{\circ}C$) by temperature Gradient Biophoto Recorder TN-1120 (Tokyo, Japan).

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2005년도 정기총회 및 제35차 춘계 학술 발표대회
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• pp.164-168
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• 2005

복합생균제를 급여하지 않은 대조구, 복합생균제 KBC1144 0.1% 급여구(T1), YC2000 0.1% + KBC1144 0.1% 급여구(T2)로 실험한 결과 일반성분에서 수분과 조회분은 유의적인 차이가 없었고, 조단백질은 T2 처리구가 가장 높았고, 조지방은 T2 처리구가 가장 낮게 나타났으며, pH는 대조구가 처리구들에 비하여 낮게 나타났다. 보수력은 대조구가 가장 높고, T1 처리구가 가장 낮게 나타났다. 콜레스테롤 함량은 처리 간에 유의적인 차이는 보이지 않았으나 두 가지 미생물제재를 활용한 T2 처리구가 가장 낮은 경향이었다. T2 처리구가 육색의 적색도는 높고, 지방색의 명도는 높고 황색도는 낮았다. 조직감은 T1 처리구가 높고, T2 처리구가 낮았으며 가열육의 관능검사에서 다즙성은 처리구들이 대조구보다 높았다. 필수지방산인 리놀산과 아라키돈산은 T1 처리구가 다른 두 구에 비하여 높게 나타났고, 불포화지방산, 필수지방산 및 필수지방산/불포화지방산 비율은 T1 처리구가 가장 높고 T2 처리구가 가장 낮게 나타났으며 아미노산 함량은 T2 처리구가 다른 두 구에 비하여 높았다. 종합적으로 두 복합미생물제재를 혼합 사용한 T2 처리구가 무항생제 돈육 생산을 가능하게 하였으며, 육질 특성면에서도 가장 좋은 결과였다.

• 한국진공학회지
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• 제17권3호
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• pp.183-188
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• 2008

내각준위 X선 광전자 분광법을 이용하여 Pt(111) 표면 위에 증착된 Fe 초박막의 산소 흡착에 대한 연구를 수행하였다. 6개 단층 이하의 두께를 갖는 Fe 초박막을 상온에서 산소에 노출시켜 산소 원자가 화학흡착된 것을 확인하고, 후열처리 과정에 따른 탈착 및 Fe층의 변화를 살펴보았다. 흡착된 산소 원자는 $600{\sim}700K$에서 부분적으로 탈착되고, 700 K 이상에서 Fe 원자들이 Pt 기판 안으로 섞여 들어감을 내각준위 스펙트럼 세기들로부터 알 수 있었다. Fe 원자들과 Pt 원자들 간의 섞임은 산소가 흡착되지 않은 경우와 거의 동일한 경향을 보였으며, 섞임에 의한 Fe-Pt 합금의 형성은 Fe $2p_{3/2}$ 광전자 스펙트럼의 속박에너지의 변화로부터 확인할 수 있었다. 탈착되지 않고 남은 산소의 양은 전체의 1/2로서 속박에너지가 $600{\sim}700K$ 사이에서 탈착된 산소보다 약 1.3 eV 커서 Fe층 위에 흡착된 산소들과는 다른 상임을 알 수 있었다. 이들 산소 원자는 1000 K에서야 탈착되었다.

• 한국수소및신에너지학회논문집
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• 제13권3호
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• pp.169-180
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• 2002

Rayleigh scattering and laser induced predissociative fluorescence are used to obtain two-dimensional images of temperature and species concentration in a laminar non-premixed flame of a diluted hydrogen jet. Rayleigh scattering cross-sections are experimentally obtained at 248nm. Planar images of OH and $O_2$ with tunable KrF excimer laser which has a) $0.5cm^{-1}$ linewidth, b) 0.5nm tuning range, c) 150mJ pulse energy, and d) 20ns pulse width are obtained to determine spatial distributions of OH and $O_2$. The technique is based on planar laser induced predissociative fluorescence (PLIPF) in which collisional quenching is almost avoided because of the fast predissociation. Dispersed LIPF spectra of OH and $O_2$ are also measured in a flame in order to confirm the excitation of single vibronic state of OH and $O_2$. OH and $O_2$ are excited on the $P_2$(8) and $Q_1$(11) line of the $A^2{\Sigma}^{+}({\nu}^{'}=3)-X^{2}{\Pi}({\nu}^{''}=o)$ band and R(17) line of the Schumann-Runge band $B^{3}{\Sigma}_{u}{^-}(\nu^{'}=0)-X^{3}{\Sigma}_{g}{^-}({\nu}^{''}=6)$, respectively. Fluorescence spectra of OH and Hot $O_2$ are captured and two-dimensional images of the hydrogen flame field are successfully visualized.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권1호
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• pp.43-51
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• 2002

The cloning and expression of $\beta-glucosidase$ II, encoded by the gene ${\beta}glu2$, from thermotolerant yeast Pichia etchellsii into Escherichia coli is described. Cloning of the 7.3 kb BamHI/SalI yeast insert containing ${\beta}glu2$ in pUC18, which allowed for reverse orientation of the insert, resulted in better enzyme expression. Transformation of this plasmid into E. coli JM109 resulted in accumulation of the enzyme in periplasmic space. At $50^{\circ}C$, the highest hydrolytic activity of 1686 IU/g protein was obtained on sophorose. Batch and fed-batch techniques were employed for enzyme production in a 14 L bioreactor. Exponential feeding rates were determined from mass balance equations and these were employed to control specific growth rate and in turn maximize cell growth and enzyme production. Media optimization coupled with this strategy resulted in increased enzyme units of 1.2 kU/L at a stabilized growth rate of $0.14\;h^{-l}$. Increased enzyme production in bioreactor was accompanied by formation of inclusion bodies.

• 한국식품과학회지
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• 제29권5호
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• pp.999-1005
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• 1997

김치 발효중 대장균군의 잔존 현상을 확인하였고 대장균군을 가식 기간에서도 조기에 사멸시킬 수 있는 방법을 모색하였으며 동시에 nisin의 김치 발효에서의 역할을 평가하였다. 대장균(E. coli B34)을 김치 제조시 $10^6\;CFU/g$이 되도록 접종하였을 때 pH, 산도의 변화, 총균수, 총젖산균수, Leuconostoc속 젖산균의 수 등에 차이가 거의 없었다. AITC 그 자체나 AITC를 생성하게 하는 고추냉이, 그리고 김치제조시 정상적으로 첨가하는 마늘이 대장균군에 대한 조기사멸효과가 있었는데, 마늘은 2.0% 이상, AITC는 50ppm이상, 고추냉이가루 0.4%이상에서 대장균군의 사멸효과가 좋게 나타났으나, nisin의 경우는 $100{\sim}2000\;I.U./g$에서 대장균군이 대조구보다 더 오랫동안 잔존하였으며 김치의 저장성 연장효과는 미미하였다. MMTSOO나 겨자가루는 대장균군 조기사멸효과가 나타나지 않았다. 김치 재료로 쓰이는 원료중에서 절인 배추에는 $10^4$, 깐마늘에는 $10^2{\sim}10^5$, 고춧가루에는 $10^4{\sim}10^5$, 생강에는 $10^7$, 그리고 파에는 $10^3{\sim}10^5\;CFU/g$의 대장균군이 존재하였다. 통마늘과 공장생산 고춧가루에는 대장균군이 검출되지 않았다.

• Journal of Microbiology and Biotechnology
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• 제23권7호
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• pp.913-922
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• 2013

An agar-degrading bacterium was isolated from red seaweed (Gelidium amansii) on a natural seawater agar plate, and identified as Saccharophagus sp. AG21. The ${\beta}$-agarase gene from Saccharophagus sp. AG21 (agy1) was screened by long and accurate (LA)-PCR. The predicted sequence has a 1,908 bp open reading frame encoding 636 amino acids (aa), and includes a glycosyl hydrolase family 16 (GH16) ${\beta}$-agarase module and two carbohydrate binding modules of family 6 (CBM6). The deduced aa sequence showed 93.7% and 84.9% similarity to ${\beta}$-agarase of Saccharophagus degradans and Microbulbifer agarilyticus, respectively. The mature agy1 was cloned and overexpressed as a His-tagged recombinant ${\beta}$-agarase (rAgy1) in Escherichia coli, and had a predicted molecular mass of 69 kDa and an isoelectric point of 4.5. rAgy1 showed optimum activity at $55^{\circ}C$ and pH 7.6, and had a specific activity of 85 U/mg. The rAgy1 activity was enhanced by $FeSO_4$ (40%), KCl (34%), and NaCl (34%), compared with the control. The newly identified rAgy1 is a ${\beta}$-agarase, which acts to degrade agarose to neoagarotetraose (NA4) and neoagarohexaose (NA6) and may be useful for applications in the cosmetics, food, bioethanol, and reagent industries.

• Environmental Engineering Research
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• 제11권3호
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• pp.134-142
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• 2006

The treatment of high-strength swine wastewater by anaerobic digestion combined with an aquatic plant system was investigated. Anaerobic digestion of swine wastewater gave volatile solids (VS) removal efficiencies of 43.3%, 52.1% and 54.5% for hydraulic retention times (HRTs) of 20, 30, 40 days, respectively. The removal efficiencies of VS, total chemical oxygen demand (TCOD) and soluble chemical oxygen demand (SCOD) decreased with increasing VS volumetric loading rate (VLR). Higher organic removal efficiency was observed at longer HRTs for the same VS volumetric loading rate. As VS volumetric loading rate increased, biogas production increased and the methane content of the biogas decreased. Experiments using duckweed (Lemna species) as an aquatic macrophyte gave the following results. In the case of nitrogen, removal efficiency was above 60% and effluent concentration was below 10.0 mg/L when the influent ammonia-N loading was about $1.0\;g/m^2/day$. In the case of phosphorus, removal efficiency was above 55% and effluent concentration was below 2.0 mg/L when the influent $PO_4$-P loading was about $0.15\;g/m^2/day$. In addition, crude protein and phosphorus content of duckweed biomass increased from 15.6% to 41.6% and from 0.8% to 1.6%, respectively, as the influent nutrient concentration increased. The treatment of high-strength swine wastewater by anaerobic digestion combined with an aquatic plant system offers good performance in terms of organics and nutrient removal for relatively low operation and maintenance costs. The results indicate that under appropriate operational conditions, the effluent quality is within the limits set by Korean discharge criteria.

• Fisheries and Aquatic Sciences
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• 제20권10호
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• pp.24.1-24.8
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• 2017

The experiment was conducted to investigate the effects of different algae in diet on growth, survival, and interleukin-10 productions of sea cucumber. At first, a 9-week feeding trail was conducted to evaluate the growth performance and survival of the sea cucumber fed one of the six experimental diets containing ST (Sargassum thunbergii), UL (Ulva lactuca), UP (Undaria pinnatifida), LJ (Laminaria japonica), SS (Schizochytrium sp.), and NO (Nannochloropsis oculata) in a recirculating aquaculture system. The result showed that survival was not significantly different among the dietary treatments, and the specific growth rate (SGR) of sea cucumber fed the UL diet ($1.58%d^{-1}$) was significantly higher than that of sea cucumber fed the other diets (P < 0.05), except for the LJ and NO diets. Secondly, interleukin (IL)-10 gene expression was determined where mice splenocytes were stimulated with $10{\mu}g\;ml^{-1}$ of sea cucumber extracts for 2 h. The result showed that IL-10 gene expression levels were significantly increased in UL, LJ, and NO diets fed sea cucumber extracts compared to other experimental diets. The results suggest that dietary inclusion with Ulva lactuca, Laminaria japonica, and Nannochloropsis oculata algae may improve the growth of juvenile sea cucumber and could upregulate IL-10 gene expression in mice splenocytes. Such detailed information could be helpful in further development of more appropriate diets for sea cucumber culture.

• 한국보건간호학회지
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• 제4권1호
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• pp.25-35
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• 1990

This study examined the evaluation of the information effects of the teaching on knowledge and daily activities of open heart surgery patients between 2 and 6 weeks after discharge. The subject was 29 patients being taught with teaching materials at discharge as experimental group, 20 patients who received no education as control group among the patients who had undergone open heart surgery in S.N.U.H. And research method was non-equivalent control group non-synchronized quasi-experimental design. As the tool of this study, 30 items of knowledge measurement scale which was extracted among the content of teaching materials to evaluate the effect of education and 28 items of which were designed to measure the daily activities of patients with myocardial infarction for the estimation of the degree of observance in daily activities were used. For data analysis, frequency, t-test, Pearson's correlation coefficient and Cronbach's $\alpha$ were used. The result were as follows; 1. Informations given through teaching materials were effective for increasing the knowledge of the patient with open heart surgery. The knowledge of patients increased to the top level (p<0.05) in 2 weeks after discharge. In control group, the knowledge level of patients did not increase after discharge. 2. The knowledge level daily activity of the experimental group was somewat higher than that of the control group, but there was no significant difference. The score .of the experimental group was 69.66 in 6 weeks after discharge much less than the top level score 112. 3. The correlation between knowledge and daily activities was not significant, suggesting the fact that the increase of knowledge did not influence the daily activities significantly. Recommendation was suggested that; 1) Further studies might be .needed with the increasing numbers of the subjects. 2) Daily activities of the patients with open heart surgery should be investigated for long term period until they recovered normal activities.