• 한국식품과학회지
• /
• 제43권2호
• /
• pp.134-141
• /
• 2011

본 연구는 들깻잎과 들깻잎 생산환경을 대상으로 276개의 시료를 채취하여 B. cereus를 분리 하였다. 분리된 B. cereus 200주의 toxicity를 평가하고자 독소유전자와 항생제내성을 검색하였다. 그 결과 분리된 균주에서 11개의 서로 다른 독소유전자 패턴은 확인하였으며 5개의 설사형독소와 구토형 독소를 모두 생성할 수 있는 균주는 21%였다. 가장 빈번하게 검출되는 독소유전자는 nheA(100%), enFM(100%), hblA, C, D(66.5%)였으며 EM은 가장 낮은 빈도(21.0%)로 검출되었다. 항생제 내성평가결과 분리된 대부분의 B. cereus는 18종의 항생제 중 10개의 항생제에 대해서는 감수성이었으나 ${\beta}$-lactam계 항생제인 penicillin(100%), ampicillin(100%), oxacillin(94.9%), amoxicillin-clavulanic acid(95.6%), cefazolin(78.2%)과 비${\beta}$-lactam계 항생제 rifampicin(58.0%)에 대해서 저항성을 보이는 것으로 나타났다. 들깻잎과 들깻잎 생산환경에서 분리된 B. cereus의 독소유전자와 항생제내성 패턴은 서로 유사하였다. 따라서 본 연구결과는 들깻잎에 오염된 B. cereus에 의하여 설사형 뿐만 아니라 구토형 식중독이 발생할 가능성을 시사하며 들깻잎과 생산환경에서 항생제 저항성 B. cereus가 검출되어 의약계뿐만 아니라 농업현장에서도 항생제내성균주 출현을 예방하는 대책이 요구된다.

• 생명과학회지
• /
• 제20권10호
• /
• pp.1549-1555
• /
• 2010

Streptococcus suis는 사람과 돼지에서 다양한 감염을 유발하는 병원체이다. 2004년부터 2009년까지 경북지방 양돈장에서 병성감정 의뢰한 돼지 가검물을 대상으로 S. suis를 분리하여 생화학적 성상, 약제감수성 시험 및 PCR을 이용한 동정을 실시한 결과는 다음과 같다. 40개 농장에서 분리한 61주의 S. suis에 대하여 생화학적 성상시험 결과 모두 S. suis로 동정되었으며, VP 음성, hippurate, esculin, arginine decarboxylase 양성, lactose 분해능이 있는 것으로 나타났다. Trehalose와 starch 분해능은 비교적 높게 나타났으며 생화학적 성상에 따른 phenotype은 11형으로 나누어졌다. 항생제 감수성 시험 결과 대부분의 균주가 amoxicillin/clavulanic acid, ampicillin, cephalothin, cefoperazone, florfenicol에 높은 감수성을 나타내었지만 amikacin, kanamycin, neomycin, streptomycin, erythromycin, clindamycin, tetracycline에는 높은 내성을 나타내었다. 16S-rRNA 특이유전자 부위를 이용한 PCR 결과 공시균주 모두 304 bp에서 증폭산물이 관찰되었다. 이들 결과는 국내에서 사육되고 있는 돼지에서 S. suis 감염을 예방하는데 도움이 될 것으로 기대된다.

• 대한임상검사과학회지
• /
• 제38권1호
• /
• pp.26-33
• /
• 2006

Recently, the rapid increase in extended-spectrum ${\beta}$-lactamase (ESBL) producing clinical isolates has become a serious problem. In this study, the epidemiologic features and molecular characteristics of ESBL among clinical isolates of Escherichia coli and Klebsiella pneumoniae, antibiotic susceptibility testing, genotype of the ESBL and patterns of chromosomal DNA from PFGE (pulsed field gel electrophoresis) were observed. A total of 53 ESBL-producing clinical isolates (30 of E. coli and 23 of Klebsiella pneumoniae) were collected from two university hospitals in the period of June to July in 2002 and 2003 respectively. The antibiotic resistance frequency of those 53 strains was tested by the disk agar diffusion method with the result that all the strains were resistant to cephalothin. To other antibiotics, the resistance rates of E. coli (30 isolates) were in order of ceftazidime (90.0%), cefotaxime and aztreonam (respectively 83.3%). Also, the resistance rates of K. pneumoniae (23 isolates) were in order of aztreonam (78.3%), ceftazidime (73.9%) and cefotaxime (65.3%). Also the sensitivity of ceftazidime-clavulanic acid were 100% in E. coli and 95.7% in K. pneumoniae. And the sensitivity of cefotaxime-clavulanic acid was 96.7% in E. coli and 91.3% in K. pneumoniae. The types of the ESBL genes were determined by using polymerase chain reaction (PCR). Among the 30 isolates of ESBL-producing E. coli, 6 (20.0%) have SHV only, 5 (16.7%) have TEM only and, 18 (60.0%) have both of TEM and SHV. Among the 23 isolates of ESBL-producing K. pneumoniae, 7 (30.4%) have SHV only, 2 (8.7%) have TEM only, and 14 (60.9%) have both of TEM and SHV. These results show that 52 strains, with only one exception, were confirmed as either TEM or SHV. The patterns of Xba I-digested chromosomal DNA of ESBL-producing E. coli and K. pneumoniae isolates were analyzed by PFGE. PFGE patterns of E. coli and K. pneumoniae were multiclonal, but many strains were grouped into a few types. Therefore, it seems that there were clonal outbreaks or possible horizontal spread. In conclusion, the TEM and SHV ${\beta}$-lactamase are most widely spread in E. coli and K. pneumoniae in Korea. As these types are usually carried by plasmids, the spread of these ${\beta}$-lactamase genes could compromise the future usefulness of third generation cephalosporins for the treatment of infections caused by E. coli and K. pneumoniae.

• 한국축산식품학회지
• /
• 제33권1호
• /
• pp.133-138
• /
• 2013

본 연구에서는 서울시내 256곳의 판매점에서 구입한 축산물 및 수산물에서 Enterococcus faecalis 와 Enterococcus facium을 분리하였으며 분리된 균주의 항생제 내성양상과 vancomycin 내성 유전자 보유여부를 검증하였다. 총 256개 시료 중 117개에서 E. faecalis(40.6%)와 E. faecium(5.1%)가 검출되어 45.7%의 분리율을 나타내었다. 축산물은 192개 중 105개 균주가 분리되어 54.7%의 분리율을 나타내었는데 닭고기에서 가장 높은 68.8%의 분리율을, 돼지고기에서 50.0%의 분리율을, 쇠고기에서 45.3%의 분리율을 나타내었다. 횟감어류에서는 18.8%의 분리율을 나타내었다. 분리된 균주에 대한 항생제 내성 양상은 10종의 항생제 디스크를 이용하여 검증하였다. Tetracycline의 내성률이 52.1%로 가장 높았으며, erythromycin의 내성률이 27.4%로 두 번째로 높게 나타났다. Ampicillin과 penicillin는 1개의 균주를 제외하고는 모두 감수성을 보였으며, amoxicillin & clavulanic acid에는 모든 균주가 감수성을 보였다. Vancomycin에는 모든 균주가 감수성을 보여 VRE는 검출되지 않았다. 분리된 균주의 vancomycin 내성유전자의 검출은 multiplex PCR을 이용하여 vanA gene과 vanB gene 보유여부를 확인하였다. vanA gene이 검출된 균주는 없었으나, vancomycin에 감수성을 나타내던 9개의 균주에서 vanB gene이 검출되어 VRE균 출현의 잠재적인 가능성을 보여주었다.

• 한국축산식품학회지
• /
• 제38권5호
• /
• pp.1055-1063
• /
• 2018

The aim of study was to investigate the correlation between the level of 17 antibiotic residues and 6 antibiotic resistances of Escherichia coli isolates in chicken meats. A total of 58 chicken meats were collected from retail grocery stores in five provinces in Korea. The total detection rate of antibiotic residues was 45% (26 out of 58). Ten out of 17 antibiotics were detected in chicken meats. None of the antibiotics exceeded the maximum residue level (MRLs) in chicken established by the Ministry of Food and Drug Safety (MFDS). The most detected antibiotics were amoxicillin (15.5%), followed by enrofloxacin (12.1%) and sulfamethoxazole (10.3%). In a total of 58 chicken meats, 51 E. coli strains were isolated. E. coli isolates showed the highest resistance to ampicillin (75%), followed by tetracycline (69%), ciprofloxacin (65%), trimethoprim/sulfamethoxazole (41%), ceftiofur (22%), and amoxicillin/clavulanic acid (12%). The results of study showed basic information on relationship between antibiotic residue and resistance for 6 compounds in 13 chicken samples. Further investigation on the antibiotic resistance patterns of various bacteria species is needed to improve food safety.

• 한국동물위생학회지
• /
• 제29권3호
• /
• pp.297-308
• /
• 2006

Fowl typhoid (FT) is a septicemic disease caused by Salmonella gallinarum. The purpose of this study was to investigate the antimicrobial resistance and pulsed -field gel electrophoresis (PFGE) patterns of S gallinarum isolated from broiler. During 1999 to 2004, there was isolated a total of 26 strains in liver and spleen. The biochemical characteristics of S gallinarum isolates was nonmotile, no production of $H_2S$, glucose gas, non-fermented rhamnose, indole-negative, fermentation of dulcitol, mannitol, maltose, and ornithine decarboxylase. At antimicrobial susceptibility, all of isolates were susceptible to amoxicillin/clavulanic acid, amikacin, neomycin, kanamycin, and cephalothin. Twenty-six isolates were divided into 19 resistant patterns and 6 strains was 8-multi-drug resistance. PFGE of Xba I restriction fragments of S gallinarum isolates was 22 patterns.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제19권4호
• /
• pp.383-394
• /
• 1997

This study was done to examine adherence of oral bacteria to titanium dental implant and to know the effective prophylactic antibiotics using an in vivo model. Three samples each of the implant material were set in an acrylic resin flange and placed in the maxillary buccal sulcus of twenty volunteers. At 6- and 54-hour intervals, each sample was placed on blood agar plate (BAP) and chocolate agar, and then they were incubated and identified. Also antibiotic susceptibility test was performed. The results obtained mere as follows ; 1. The microorganisms were chain-like Gram positive cocci and staphyline Gram positive cocci, Gram positive bacilli in order of frequency were found at 6-hour and 54-hour samples by Gram staining. 2. Streptococci was found predominantly at both 6-hour and 54-hour samples, but number of streptococci was decreased as compared to 6-hour samples. 3. There was no difference in the bacterial species adherent to implant between 6-hour and 54-hour samples. 4. All the microbes were sensitive to AMC (amoxacillin clavulanic acid), chloramphenicol, quinolone and vancomycin in the antibiotic susceptibility test. Above results suggest that streptococcus are mainly adhered to titanium implant after implant was placed in the oral cavity and AMC is the most recommendable antibiotics to prevent the peri-implant inflammation.

• 대한수의학회지
• /
• 제47권1호
• /
• pp.43-50
• /
• 2007

Staphylococci are Gram-positive, facultatively anaerobic cocci, normally found on the skin andmucosal surfaces of most warm-blooded animals and often involved in a wide variety of diseases in animals.Staphylococcal infections are treated with antibiotics and, consequently, antibiotic resistance and/or acquiredresistance have developed. Staphylococcus (S.) intermedius and Staphylococcus (S.) aureus are 2 comonveterinary isolates that are frequently associated with suppurative infections. This study was undertaken toexamine antimicrobial susceptibility of S. aureus (23 isolates) and S. intermedius (160 isolates) isolatedfrom dogs in Gwangju, Korea and investigate whether the antibiotic resistance of S. aureus and S.intermedius is efected by the site of isolation, age, and sex of dogs. More isolates were isolated fromadult dogs (71.3%) than juveniles (20.5%). Antimicrobial resistance was commonly found for Penicillin,Tetracycline, Trimethoprim-Sulphamethoxazole in both Staphylococcus species. All of the isolates weresusceptible to Amoxicillin/Clavulanic Acid, Cephalothin, Oxacilin, Neomycin, and Vancomycin. Appropriateprotocol for antibiotic use and strategies to reduce antimicrobial resistance rate will be needed. Periodicsubstitution of antimicrobial agents and limitation of antibiotic use should also be considered.

• 한국동물위생학회지
• /
• 제32권2호
• /
• pp.155-163
• /
• 2009

Fowl typhoid (FT) is a septicemic disease caused by Salmonella Gallinarum. The purpose of this study was to investigate the antimicrobial resistance and pulsed-field gel electrophoresis (PFGE) patterns of S. Gallinarum isolated from chicken. During 1999 to 2004, there was isolated a total of 100 strains in liver and spleen. The biochemical characteristics of S. Gallinarum isolates was nonmotile, no production of H$_2$S, glucose gas, non-fermented rhamnose, indole-negative, fermentation of dulcitol, mannitol, maltose, and ornithine decarboxylase. At antimicrobial susceptibility, all of isolates were susceptible to amoxicillin/clavulanic acid, amikacin, neomycin, kanamycin, norfloxacin and enrofloxacin. One hundred isolates were divided into 54 resistant patterns and 37 strains was 6-multi drug resistance. PFGE of Xba I restriction fragments of S. Gallinarum isolates was 20 patterns.

• 대한수의학회지
• /
• 제52권3호
• /
• pp.177-181
• /
• 2012

Actinobacillus (A.) pleuropneumoniae is the causative agent of pleuropneumonia which is one of the most important respiratory diseases in pigs worldwide. A total of 32 A. pleuropneumoniae isolates from diseased pigs during 2008 to 2010 were serotyped by polymerase chain reaction method. The susceptibility of the isolates to 13 antimicrobial agents were determined by disk diffusion test. In all the 32 isolates examined in this study, serotype 5 (16 isolates: 50%), 1 (7 isolates: 21.9%), 2 (5 isolates: 15.6%) and 12 (1 isolate: 3.1%) were found. Of all tested antimicrobial agents, resistance to oxytetracycline was found in 96.9% of isolates, followed by resistance to amikacin (81.2%), neomycin (68.7%), kanamycin (53.1%), penicillin (50.0%), gentamicin (43.7%), florfenicol (25.0%), ampicillin (18.7%), colistin (9.4%), trimethoprim/sulfamethoxazole, ceftiofur (8.3%), amoxicillin/clavulanic acid (3.1%) and enrofloxacin (0%). Oxytetracycline or florfenicol-resistant isolates were examined for the presence of resistance gene. Among the 31 oxytetracycline-resistant isolates, tetB, tetH and tetO genes were detected in 22 (71%), 8 (26%) and 1 (3%) isolates, respectively. The floR genes were detected in 8 (100%) of the 8 florfenicol-resistant A. pleuropneumoniae isolates.