• 한국축산식품학회지
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• 제25권3호
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• pp.357-364
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• 2005

본 연구에서는 Kefir를 $0.02\%\;NaN_3$를 포함하는 MRS agar에 도말하여 1차적으로 Lactobacillus sp.를 선발하였고, 그 중 가장 우수한 균을 최종 분리하였다. 분리된 유산균은 API kit를 이용한 당 발효성 및 생화학적 시험을 토대로 Lactobacillus rhamnosus에 $99.5\%$의 상동성을 가진 유산균종으로 동정되었다. Lactobacillus rhamnosus는 amylase와 xylanase 비활성이 0.673과 $0.288\;{\mu}mole/min/mg$으로 비교적 높은 활성을 보였다. pH 2에서 $65\%$ 이상의 강한 생존률을 나타냈고 $1.0\%$ 담즙산에서도 $72\%$가 생존하는 내성을 나타냈다. $60^{\circ}C$에서도 Lactobacillus rhamnosus는 강한 열 안정성을 나타내 대조구인 Lactobacillus acidophilus보다 100배 이상의 생존률을 보였다. 또한 Lactobacillus rhamnosus는 대장균에 첨가하여 혼합배양시 18시간 이내에 대장균을 $100\%$ 사멸시켜 높은 항균 활성을 나타냈다. Lactobacillus rhamnosus는 100ppm CTC, 50ppm OTC, 150ppm Lincomycin, 200ppm Tylosin에서는 생장이 억제되나 기타의 9가지의 항생제에 대하여는 강한 내성을 갖는 것으로 확인되었다. 이상의 결과로부터 새로 분리한 Lactobacillus rhamnosus는 소화에 관련한 효소 활성이 높고 내산성 및 내담즙산성, 열 안정성이 우수하며 높은 항균 활성을 함유하여 식품용 probiotics로 충분한 활용 가치가 있는 것으로 생각되었다.

• 한국동물위생학회지
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• 제24권1호
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• pp.31-41
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• 2001

This study was carried out to identify causative agents from california mastitis test(CMT) positive mastitic milk, and to examine the antimicrobial susceptibility of 50 heads in Seongju and Chilgok area of Gyeongbuk province. Sulfadimethoxine sodium(SMS) was intramuscularly administered once to four mastitis Infected dairy cattle at the rate of 10mg/kg body weight. After injection of SMS, the depletion rate of serum and milk from the cattle were periodically measured for five days. The CMT positive number from 50 heads showed 46% and that of 200 quarters was 47(23.5%). From 39 quarters of 47 heads 39 different microorganisms were identified. These organisms were classified into 12 species : Staphylococcus aureus 8(20.5%), Sta hemolyticus 6(15.4%), Streptococcus bovis 4(10.3%), Sta hyicus 3(7.7%), Sta epidemidis. Sta xylosus, Sta sciuri 2(5.1%), Str agalactiae 2(5.1%), Escherichia coli(10.3%), three Enterobacter cloacae(7.7%), two Ent aerogenes(5.1%) and one Salmonella spp(2.6%). As the results of antibiotic susceptibility test, gentamicin(Gm, 11 species 27 strains, 69.5%), cephalotin(Cf, 9 species 24 strains, 61.5%), sulfamethoxazole(Stx, 8 species 14 strains, 43.6%), tetracycline(Tc, 8 species 14 strains, 35.9%), and streptomycin(Sm), lincomycin(Lm), cefoperazon(Cp) and penicillin(Pc) have a highly resistance(7.7% ～5.1%). However, carbenicillin (Cb), amikacin(Ah) have no susceptible for all drugs. The mean residual concentration of SMS in serum according to the time lapsed were showed 33.964 $\pm$ 4.435ppm at the 4 hours after intramuscularly injection(AII). It was significantly(p<.05) decreased to 6.596 $\pm$ 3.402, 0.217 $\pm$ 0.119 and 0.005 $\pm$ 0.004ppm at the 1st, 3rd and 5th day AII. The mean concentration of SMS in milk was significantly(p<.05) decreased from 0.920 $\pm$ 0.42ppm to 0.084 $\pm$ 0.016ppm between 8 hours and 1 day AII. As the results of this experiments, sulfadimethoxine was residued at the level of no less than 0.01ppm in milk on the 2nd day AII. Thus, this results would be able to be used the basic index for prevention of sulfonamides residue in milk after treatment of dairy mastitis.

• 대한수의학회지
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• 제20권2호
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• pp.85-92
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• 1980

The antimicrobial drug susceptibility of 439 isolates of animal pathogens recovered from various clinical cases during 1978-79 has been investigated by the use of disk diffusion technique. The majority of 308 strains of Eschericihia coli were highly resistant to bacitracin, erythromycin, penicillin, streptomycin and tetracyclinon while only 0.3 per cent of them were resistant to gentamicin and 3.2 per cent to colistin. The percentages of strains resistant to ampicillin, carbenicillin, cephalothin, chloramphenicol and neomycin were 30.5%, 24.7%, 11:4%, 28.2% and 26.2% and repectively. However, none of E. coli cultures of ovine origin were resistant to ampicillin, carbenicillin, chloramphenicol, colistin, gentamicin, kanamycin, and neomycin. A total of 39 patterns of multipe drug1 resistance of 308 strains E. coli against 9 drugs in general use such as ampicillin, cephalothin, chloramphenicol, colistin, gentamicin, kanamycin, neomycin, streptomycin and tetracycline were observed and the most common multiple resistance patterns were SM, TC pattern (20.5%) and AM, CP, KM, NM, SM, TC pattern (9.7%). None of the 43 cultures of salmonella organism from pigs and chickens were resistant to ampicillin, carbenicillin, cephalothin, colistin, gentamicin and kanamycin; and the majority of the cultures were susceptible to chloramphenicol (90.0%), neomycin (97.7%) and tetracycline (93.0%). All the cultures were found to be resistant to bacitracin and penicillin and the rate of resistant strains to erythromycin and s treptomycin being 79.1% and 41.9% respectively. It was found that the majority of 63 cultures of staphylococcal isolates were resistant to lincomycin, penicillin, streptomycin and tetracycline. The percentages of 63 staphylococcal isolates susceptible to gentamicin, nitrofurantoin, cephalothin, ampicillin, methicillin, bacitracin and chloramphenicol were 98.4%, 98.4%, 95.2%, 93.7%, 93.7%, 92.1% and 92.1% respectively. The 25 cultures of streptococcal isolates were resistant in order of prevalence to streptomycin(88.0%), kanamycin(68.0%), gentamicin (44.0%), tetracycline (44.0%) and methicillin (40.0%) wihle the majority of them were sensitive to ampicillin, bacitracin, chloramphenicol and penicillin.

• 미생물학회지
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• 제42권4호
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• pp.265-270
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• 2006

본 연구에서는 2005년 11월부터 2006년 3월 초까지 497개의 초밥, 김밥, 샌드위치 등의 식사대용 식품 검체를 수거하여 식품공전을 토대로 식사대용 식품에서 유래되는 미생물학적 인 오염도를 조사하고, 현대 사회에서 항생제 사용의 오남용으로 항생제 내성이 심각한 상황을고려하여 분리된 균에 대한 항생제 감수성 양상에 대하여 알아보고자 하였다. 수거된 검체를 실험한 결과 김밥에서 4개(1.4%)의 Escherichia coli가 분리되었고, 초밥, 샌드위치 등에서는 분리되지 앓았다. 또한 김밥에서 12개(4.4%), 초밥에서 8개(5.4%), 샌드위치에서 2개(4.3%)로 총22개(4.4%)의 Staphylococcus aureus가 분리되었다. 식사대용 식품에서 분리된 26개의 균주로 National Committee for Clinical Laboratory Standards (NCCLS)의 기준에 의거하여 vancomycin, teicoplanin, gentamycin, cipro-floxacin, synercid, cefotaxime, lincomycin, meropenem, cefazolin, amoxicillin-clavulanic acid으로 총 10개의 항생제를 사용하여 E. coli와 S. aureus의 항생제 감수성 양상을 파악해 보고자 하였다. 실험 결과 식사대용 식품에서 분리된 E. coli 4균주의 항생제 감수성 양상은 그람 음성균 치료에 주로 사용되는 항생제인 gentamycin, ciprofloxacin, cefotaxine, meropenem, cefazolin에 대해서는 감수성이 높다고 판단되었으나 amoxicillin-clavulanic acid에 대해서는 내성을 나타내었고, S. aureus의 항생제 감수성은 비교적 높다고 판단되었다.

• 대한수의학회지
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• 제26권2호
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• pp.283-292
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• 1986

Isolation and identification of Mycoplasma were performed to clarify Mycoplasma infection of mice fed by conventional feeding at two ($K_1$, $K_2$) institutes in Korea. The twenty mice to be tested were randomly sampled from each of 10 breeding colonies in respective institute. Identification of the Mycoplasma strains isolated from the nasal cavity, lung and synovia of mice was made according to the morphology of colonies, biological and biochemical properties with special reference to M. pulmonis, M. arthrotodis and M. neurolyticum. In addition, growth inhibition test was performed using hyperimmune rabbit antisera to the strain PG-22 of M. pulmonis, the strain PG-6 of M, arthritidis and the strain PG-28 of M. neurolyticum and also differentiation of isolates from L-form bacteria was dont by Dieses staining and culture method with passage of the isolates on liquid media eliminated antibacterial drug. On the other hand, a total of 13 strains out of the 44 isolated M. pulmonis from mice was investigated for their susceptibility against 16 antibiotics in vitro. The antibiotic sensitivity test was made using $3{\times}10^4$ organisms/0.3ml on each plate(90mm diameter) with antibiotic mono-or tri-disk. The results obtained are summarized as follows: 1. Out of 20 mice from 10 breeding colonies in Kl institute, mycoplasma-like strains from the nasal cavity of 16 mice(80%) and from the lung of 8 mice(40%) were isolated, while out of 20 mice in K2 institute, M-like strains were isolated from the nasal cavity of 14 mice(70%) and from the lung of 6 mice(30%). However, no mycoplasma-like organisms were isolated from the synovia of the 40 mice examined. All the 44 strains isolated were identified as the organisms of M. pulmonis. 2. Out of the 16 antibiotics tested, penicillin, oleandomycin and bacitracin showed no activity against all the 13 M. pulmonis strains. On the contrary, lincomycin, clindamycin, chloramphenicol, tetracycline, minocycline, kanamycin, gentamycin and tobramycin showed high activity with three different antibiotic concentration of tridisk, but amikasin and spiramycin showed intermediate activity. Other antibiotics such as polymyxin B and colistin showed low activity, while erythromycin showed lower activity than others.

• 대한치과보철학회지
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• 제41권2호
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• pp.207-222
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• 2003

As a material of metal-ceramic prosthesis, nickel as a form of Ni-Cr alloy has been used for many dental prostheses in many cases. However, several problems in use of the alloy have been revealed (ex ; tissue stimulation, skin allergy, hypersensitivity cytotoxicity and carcinogenecity). Little is known about nickel with respect to the relationship between Ni-prosthesis and gaining of Niresistance in oral microorganisms. The present study was undertaken to check whether use of Ni-prosthesis leads to occurrence of Ni-resistant microorganisms. So this study may suggest the possible relationships between the oral microorganisms and nickel-resistance in oral environment. Bacteria were isolated from the gingival crevicular fluid on the patients wearing Ni-Cr prosthesis. The isolated bacteria were tested fir their Ni-resistance in nickel containing media at different concentration from 3mM to 110mM. E. coli HB101 was used as control. The Ni-resistant bacteria were isolated and biochemically identified. The Ni-resistant bacteria were tested several biochemical, molecular-biological tests. Performed tests were : measuring the growth curve, antibiotic test, growth ability test in liquid media, isolation of the chromosome and plasmid, digestion of DNA by restriction enzyme, electrophoresis of chromosome and plasmid DNA, identification of Ni-resistant genes by the DNA hybridization. The results were as follows 1) The bacteria isolated from gingival crevicular fluid on the patients wearing Ni-Cr alloy prosthesis showed nickel-resistance. 2) The isolated microorganisms grew at nickel containing media of high concentrations (60mM-110mM). 3) Based on the biochemical tests, the isolated microorganisms were identified as Enterococcus faecalis(13 cases), Klebsiella pneumoniae(1 case) and Enterobacter gergoviae(1 case). 4) Enterococcus faecalis expressed not only nickel resistance but also the multi-drug resistance to several antibiotics ; chloramphenicol, kanamicin, streptomycin, lincomycin, clindamycin, However, all strain showed the sensitivity against the tetracycline. 5) DNA hybridization result suggests that there is no homology between the previously known gene of nickel resistance in Klebsiella pneumoniae and chromosomal DNA of Enterococcus faecalis.

• 상하수도학회지
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• 제36권2호
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• pp.107-119
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• 2022

The frequent detection and occurrence of micropollutants (MPs) in aquatic ecosystems has raised public health concerns worldwide. In this study, the behavior of 50 MPs was investigated in three different domestic wastewater treatment plants (WWTPs). Furthermore, the Kruskal-Wallis test was used to assess the geographical and seasonal variation of MPs in the WWTPs. The results showed that the concentrations of 43 MPs ranged from less than 0.1 to 237.6 ㎍ L^-1, while other seven MPs including 17-ethynylestradiol, 17-estradiol, sulfathiazole, sulfamethazine, clofibric acid, simvastatin, and lovastatin were not detected in all WWTPs. Among the detected MPs, the pharmaceuticals such as metformin, acetaminophen, naproxen, and caffeine were prominent with maximum concentrations of 133.4, 237.6, 71.5, and 107.7 ㎍ L^-1, respectively. Most perfluorinated compounds and nitrosamines were found at trace levels of 1.2 to 55.3 ng L^-1, while the concentration of corrosion inhibitors, preservatives (parabens), and endocrine disruptors ranged from less than 0.1 to 4310.8 ng L^-1. Regardless of the type of biological treatment process such as MLE, A2O, and MBR, the majority of pharmaceuticals (except lincomycin, diclofenac, iopromide, and carbamazepine), parabens (except Methyl paraben), and endocrine disruptors were removed by more than 80%. However, the removal efficiencies of certain MPs such as atrazine, DEET, perfluorinated compounds (except PFHxA), nitrosamines, and corrosion inhibitors were relatively low or their concentration even increased after treatment. The results of statistical analysis reveal that there is no significant geographical difference in the removal efficacy of MPs, but there are temporal seasonal variations in all WWTPs.

• Current Research on Agriculture and Life Sciences
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• 제2권
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• pp.115-121
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• 1984

1984년(年) 10월(月)부터 1985년(年) 8월말(月末)사이에 대학부속가축병원(大學附屬家畜病院)에 검진의뢰(檢診依賴)된 대구(大邱) 경북지방(慶北地方)에서 발생(發生)한 83례(例)의 만성(慢性) 유방염(乳房炎)의 원인균(原因菌)을 분리(分離) 동정(同定)하고 이 분리균(分離菌)의 각종(各種) 항생제(抗生劑)에 대한 감수성(感受性)을 disc diffusion technique로 조사(調査)하였다. 대구(大邱) 경북지방(慶北地方)에서 문제되는 만성(慢性) 유방염(乳房炎)은 포도구균성 유방염(乳房炎)이 전체의 48.2%(83례중(例中) 40례(例))로 가장 많았으며 그 다음은 대장균군(大腸菌群) 유방염(乳房炎)으로 18.1%(83례중(例中) 15례(例))를 차지하였다. 효모양진균에 의한 유방염(乳房炎)도 10.8%(83례중(例中) 9례(例))나 되었다. Corynebacterium spp.에 의한 유방염(乳房炎)은 8.4%였으나 연쇄구균성 유방염(乳房炎)은 3.6%에 지나지 않았다. Bacillus spp.와 pseudomonad에 의한 것은 각각 3.6%와 8.4%이었으며 만성(慢性) 유방염(乳房炎)의 원인균(原因菌)을 밝힐 수 있었던 것은 4.8%(83 례중(例中) 4례(例))이였다. 만성(慢性) 유방염(乳房炎)에 관여한 포도구균과 대장균(大腸菌)은 공시(供試)한 항상제(抗生劑)에 대하여 내성(耐性)을 나타내는 경향이 뚜렷하였다. 포도구균은 penicillin, methicillin, linocomycin, novobiocin, ampicillin, tetracycline에는 각각 87.2%, 78.7%, 68.1%, 61.7%, 57.4%가 내성(耐性)인 반면에 gentamicin, cephalothin, chloramphenicol, erythromycin 등에는 각각 78.7%, 76.6%, 74.5%, 63.7%가 감수성(感受性)이었다. 대장균(大腸菌)은 streptomycin과 cephalothin에는 72.2%, tetracycline에 66.7%, ampicillin에 61.1%가 내성(耐性)인 반면에 colistin, gentamicin, chloramphenicol, neomycin에는 각각 83.3%, 77.8%, 66.7%, 55.6%가 감수성(感受性)이었다. Corynebacterium spp.는 ampicillin, chloramphenicol, erythromycin, gentamicin, oleandomycin, tetracycline에는 감수성(感受性)이었으나 novobiocin과 penicillin 등에는 내성(耐性)이었다. 한편 pseudomonas aeruginosa는 공시(供試)한 모든 항생제(抗生劑)에 내성(耐性)이었다.