• 한국수산과학회지
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• 제51권4호
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• pp.397-403
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• 2018

We determined the resistance rates of pathogenic bacteria isolated from cultured olive flounder Paralichthys olivaceus to erythromycin (Em), antibiotic typically used in aquaculture and analyzed the genotypes of resistant bacteria using polymerase chain reaction (PCR). We isolated and utilized 160 isolates of Streptococcus parauberis, 1 of S. iniae, 66 of Edwardsiella tarda, 56 of Vibrio sp. and 23 of unidentified bacteria from presumed infected olive flounder from Jeju Island from March 2016 to October 2017. Of the 306 isolated strains, Em-resistant strains included 33 of S. parauberis, 39 of E. tarda and 2 of Vibrio sp. We conducted PCR to assess the resistance determination of Em-resistant strains. Five different types of Em-resistance genes were detected in the 74 Em-resistant strains: erm (A), erm (B), erm (C), mef (A) and mef (E); erm (A) and erm (B) were detected in 1 (3%) and 24 (72.7%) S. parauberis isolates, respectively. In E. tarda, erm (B) was detected in five isolates (12.8 %) and no Em-resistance genes were detected in the two Vibrio sp. isolates.

• 환경위생공학
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• 제22권4호
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• pp.55-63
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• 2007

We investigated the distribution and drug susceptibility test of V. vulnificus isolated from environmental sources in Incheon. In this survey, total 4,302 samples were obtained from different sites of the Incheon coastal area during the periods from march 2004 to November 2006. Among the 4,302 samples, 310 strains were isolated. The isolation rates of Vibrio vulnificus from fish, shellfish, estuarine water and sediment were 6.7%, 4.7%, 12.4% and 23.2%, respectively. The highest isolation rate was 14.6% in September and in spite of low temperature the isolation rate was 5.1% in November. The highest rate of antibiotic resistance was observed against streptomycin(15.3%), cefazolin(8.5%), cephalothin(8.3%), amikacin(8.3%), cefoxitin(6.7%) and nalidixic acid(6.7%). Seventeen percent of isolates were observed to be resistant to two or more of the antibiotics tested.

• 미생물학회지
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• 제49권2호
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• pp.146-149
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• 2013

비브리오균은 해양 및 하구 환경에서 상재하는 균으로 그람 음성 간균, 호염성, 비포자형성의 특징을 가지고 있다. 질병과 관련된 균주로는 Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio cholera 등이 있다. 매년 어패류의 섭취 등을 통해 식중독 사고가 빈번하게 발생하고 있으며, 이에 본 연구에서는 서해안 6곳에서 패류를 채취하여 비브리오균의 분포도를 모니터링하고, 이들의 항생제 내성을 분석하였다. 총 120건의 패류를 TCBS 평판배지와 API 20E kit 기법으로 동정하였을 때 23.3%의 시료에서 비브리오균이 검출되었다. 이들 분리균주들의 항생제 내성을 16종의 항생제에 대해 분석한 결과 82.1%가 각각 vancomycin과 ampicillin에 대해 내성을 보였고, rifampin (71.4%)과 cephalothin (53.6%)에 대한 내성비율도 다른 항생제들에 비해 상대적으로 높은 것으로 나타났다. 분리균주들의 항생제 감수성은 chloramphenicol (92.9%), sulfamethoxazole/trimethoprim (92.9%)과 tetracycline (96.4%)에 대해 가장 높았다. 분리균주들의 약 71.4%가 vancomycin과 ampicillin을 포함하여 3개 이상의 항생제에 대해 다중내성을 보였다.

• 한국어병학회지
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• 제34권1호
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• pp.39-46
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• 2021

Tetracycline (TC)은 국내에서 세균 감염 치료에 반드시 필요한 대표적인 항생제로 알려져 있다. 그러나 부적절한 사용과 남용으로 인해 Tetracycline, Erythromycin, Fluoroquinolone 등과 같은 항생제에 대한 내성이 발생하고 있으며, 이는 국내 양식 분야에서 심각한 경제적 피해를 유발한다. 본 연구에서는 2015~2018년에 걸쳐 경기도 양식장의 양식생물에서 101개 균주를 분리하였다. 분리균주는 간이적인 생화학적 방법을 통해 동정하였으며, 최소 억제농도(MIC)의 확인을 통해 Oxytetracycline (OTC), Ampicillin (AMP), Clindamycin (CLI), Enrofloxacin (ENRO), Gentamycin (GEN)에 대한 내성 여부를 확인하였다. 이중 TC에 내성을 보이는 균주는 PCR법을 통해 tet 유전자의 분포를 조사하였다. 그 결과, 총 101개 균주 중에서 Aeromonas spp.가 44개(43.5%)로 가장 우점하였고, 그 다음으로 Pseudomonas spp. 4개(4.0%), Vibrio spp. 5개(5.0%)가 확인되었다. 또한, 다중 내성을 보이는 균주(77.2%)가 단일 내성균(22.8%)보다 많음을 확인하였다. tet(A), tet(D), tet(E), tet(G), tet(M), tet(S)가 TC 내성 균주에서 검출되었으며 tet(A)가 가장 우점적으로 확인되었다. Aeromonas spp.는 분리된 균주 중에서 가장 많았으며, 경기도 내 양식현장에서의 다양한 항생제 내성 유전자의 특성에 대한 추가적인 연구가 필요하다.

• Journal of Microbiology and Biotechnology
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• 제30권6호
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• pp.856-867
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• 2020

Vibrio parahaemolyticus is a major gastroenteritis-causing pathogen in many Asian countries. Antimicrobial resistance in V. parahaemolyticus has been recognized as a critical threat to food safety. In this study, we determined the prevalence and incidence of antimicrobial resistance in V. parahaemolyticus in the southern Fujian coast, China. A total of 62 isolates were confirmed in retail aquatic products from June to October of 2018. The serotype O3:K6 strains, the virulence genes tdh and trh, antibiotic susceptibility and molecular typing were investigated. Then plasmid profiling analysis and curing experiment were performed for multidrug-resistant strains. The results showed that the total occurrence of V. parahaemolyticus was 31% out of 200 samples. Five strains (8.1%) out of 62 isolates were identified as the V. parahaemolyticus O3:K6 pandemic clone. A large majority of isolates exhibited higher resistance to penicillin (77.4%), oxacillin (71%), ampicillin (66.1%) and vancomycin (59.7%). Seventy-one percent (44/62) of the isolates exhibited multiple antimicrobial resistance. All 62 isolates were grouped into 7 clusters by randomly amplified polymorphic DNA, and most of the isolates (80.6%) were distributed within cluster A. Plasmids were detected in approximately 75% of the isolates, and seven different profiles were observed. Seventy-six percent (25/33) of the isolates carrying the plasmids were eliminated by 0.006% SDS incubated at 42℃, a sublethal condition. The occurrence of multidrug-resistant strains could be an indication of the excessive use of antibiotics in aquaculture farming. The rational use of antimicrobial agents and the surveillance of antibiotic administration may reduce the acquisition of resistance by microorganisms in aquatic ecosystems.

• 대한미생물학회지
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• 제22권3호
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• pp.225-232
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• 1987

Authors studied on the isolation of V. damsela from sea water, fish and shellfish at the Keoje Hae keumkang on the southern sea and at Hongdo island and Heucksan island on the western sea of Korea from May to September in 1986. Authors investigated for the isolated strains to bacteriological identification, hemolysis about various erythrocytes and antibiotic susceptibilities. The results obtained were as follows: 1. V. damsela was isolated 14 strains from total 383 specimens; 233 cases of sea water, 40 cases of fish and 110 cases of shellfish, respectively. Eight strains were isolated from sea water and 6 strains were isolated from shellfish. 2. The biochemical characteristics which differentiate it from other Vibrio species were indole negative, ornithine negative, Voges-Proskauer positive, arginine positive, galactose positive, glucose positive, maltose positive, mannose positive, trehalose positive, and growth in nutrient broth with 1% to 6% NaCl. 3. On hemolysis reaction on blood agar media using human, rabbit and guinea pig erythrocytes, human erythrocytes were 11 strain positive, rabbit erythrocytes were 12 strain positive and guinea pig erythrocytes were 13 strain positive. 4. Senistivity test using with chemotherapeutic agents of "BioLab" Microbial Sensitivity Test Discs were generally sensitived to amikacin, ampicillin, cephalothin, chloramphenicol, clindamycin, erythromycin, gentamycin, kanamycin, methicillin, penicillin, streptomycin, tetracycline and tobramycin, respectively, but were resistant to lincomycin.

• 한국수산과학회지
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• 제27권3호
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• pp.292-298
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• 1994

식중독 원인균으로 알려진 Vibrio mimicus(V. mimicus)의 분포 상태와 이의 생리적 특성을 조사하기 위하여 1993년 1월부터 9월까지 민락동과 광안리 해수욕장 부근의 해수를 채취하여 V. mimicus의 월별 분포 상태를 실험하였으며, 여기서 분리된 균주 중에서 항생제 내성이 강한 균으로 분리, 동정된 V. mimicus K-1의 생리적 성질과 배양 특성을 조사하였다. 수온이 $16.3^{\circ}C$인 4월부터 검출되기 시작하여 8월까지 검출되었으나, 수온이 $15^{\circ}C$ 이하인 겨울철(1, 2, 3월)에는 전혀 검출이 되지 않았다. 분포 정도는 최소 0.4(MPN/100ml)에서 최고 70((MPN/100ml)으로 지역에 따라 차이가 있었다. V. mimicus K-1은 $37^{\circ}C$, pH 7.5, 그리고 염도 $0.5\%$에서 각각 최대의 증식율을 보였다. 그리고 항생제 (colistin, erythromycin, bacitracin, tetracycline, penicillin)에 대해서 내성을 나타내었다. 자외선(30W, 50m)에 대해서는 상당히 내성이 약했으며, 70초간 조사 후에는 검출이 되지 않았다. 열에 의한 치사율은 $50^{\circ}C$에서 5.7분, $60^{\circ}C$에서 2.1분, 그리고 $70^{\circ}C$에서는 0.7분 만에 최초균수의 $90\%$이상이 사멸하였다.

• Journal of Microbiology and Biotechnology
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• 제22권4호
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• pp.555-562
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• 2012

PCR was performed to analyze the ${\beta}$-lactamase genes carried by ampicillin-resistant Vibrio spp. strains isolated from marine environments in Korea between 2006 and 2009. All 36 strains tested showed negative results in PCR with the primers designed from the nucleotide sequences of various known ${\beta}$-lactamase genes. This prompted us to screen new ${\beta}$-lactamase genes. A novel ${\beta}$-lactamase gene was cloned from Vibrio alginolyticus KV3 isolated from the aquaculture water of Geoje Island of Korea. The determined nucleotide sequence (VAK-3 ${\beta}$-lactamase) revealed an open reading frame (ORF) of 852 bp, encoding a protein of 283 amino acids (aa), which displayed low homology to any other ${\beta}$-lactamase genes reported in public databases. The deduced 283 aa sequence of VAK-3, consisting of a 19 aa signal peptide and a 264 aa mature protein, contained highly conserved peptide segments specific to class A ${\beta}$-lactamases including the specific amino acid residues STFK (62-65), SDN (122-124), E (158), and RTG (226-228). Results from PCR performed with primers specific to the VAK-3 ${\beta}$-lactamase gene identified 3 of the 36 isolated strains as V. alginolyticus, Vibrio cholerae, and Photobacterium damselae subsp. damselae, indicating the utilization of various ${\beta}$-lactamase genes including unidentified ones in ampicillin-resistant Vibrio spp. strains from the marine environment. In a mating experiment, none of the isolates transfered the VAK-3 ${\beta}$-lactamase gene to the Escherichia coli recipient. This lack of mobility, and the presence of a chromosomal acyl-CoA flanking sequence upstream of the VAK-3 ${\beta}$-lactamase gene, led to the assumption that the location of this new ${\beta}$-lactamase gene was in the chromosome, rather than the mobile plasmid. Antibiotic susceptibility of VAK-3 ${\beta}$-lactamase was indicated by elevated levels of resistance to penicillins, but not to cephalosporins in the wild type and E. coli harboring recombinant plasmid pKV-3, compared with those of the host strain alone. Phylogenetic analysis showed that VAK-3 ${\beta}$-lactamase is a new and separate member of class A ${\beta}$-lactamases.

• 한국식품과학회지
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• 제42권4호
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• pp.508-513
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• 2010

2006년부터 2008년까지 3년간 시판 수산물 2,239건에서 분리한 V. parahaemolyticus에 대한 항생제 감수성 결과는 다음과 같았다. 어류 789건을 검사하여 42주(5.3%)의 V. parahaemolyticus가 분리 동정되었으며, 패류 735건 중 27건(3.7%), 연체류 387건 중 12건(3.1%), 기타 수산물 328건 중 12건(3.7%), 총 93건(4.2%)에서 V. parahaemolyticus가 분리 동정되었다. 내성률이 높은 항생제는 ampicillin 93.5%, cephalothin 90.3%, streptomycin 87.1%, ticarcillin 55.9%, 그리고 amikacin 40.9%이었으며, 감수성률이 높은 항생제는 nalidixic acid, chloramphenicol 및 ampicillin/sulbactam trimethoprim/sulfamethoxazole 98.9%, gentamicin 및 tetracycline 82.8%, ceftriaxone 63.4%이었다. 중등도 내성률은 kanamycin 79.6%, ciprofloxacin 64.5%, amikacin 47.3%, cefoxitin 43.0%순이었다. 항생제 내성양상은 3제 내성이 37.6%, 4제 내성 24.7%, 5제 내성 17.2%, 6제 내성 11.8%, 2제 내성6.5%, 7제 내성 2.2% 순이었으며, 가장 많은 내성 양상은 AM-CF-S의 3제 내성(22.6%), AM-CF-S-TIC 4제 내성(18.3%), AM-AN-CF-S-TIC 5제 내성(9.7%) 순이었다.

• 한국어병학회지
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• 제37권1호
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• pp.133-138
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• 2024

This study is a report on combinational effects between four sesquiterpene lactones (SLs) from bay laurel (Laurus nobilis) leaves, and oxytetracycline (OTC) or amoxicillin (AMX) against four fish pathogenic bacteria such as Vibrio anguillarum, V. harveyi, Edwardsiella tarda, and Streptococcus iniae. Individually, four SLs exerted little antibacterial activity against fish pathogenic bacteria. However, when combined with OTC or AMX, they showed synergistic interaction against pathogenic bacteria. Especailly, zaluzanin C (1) reduced the MIC of OTC (or AMX) eight-fold. Our results showed that combinations of SLs with antibiotics (ABTs) are more effective than ABTs alone to control pathogenic bacteria. The highest synergistic effect was observed when zaluzanin C (1) was combined with OTC or AMX against V. harvey or S. iniae, displaying significant reductions of MICs up to 8-fold (0.125 to 0.015 ㎍/mL and 0.0078 to 0.0009 ㎍/mL). In addition, zaluzanin C (1) improved the antibiotic potency of OTC against OTC resistant V. harveyi (250 ㎍/mL to 62.5 ㎍/mL). Synergism between ABTs and phytochemical such as SLs could be a therapeutically helpful concept to improve the efficacy of ABTs and prevent antibiotic resistance. These results suggest that SLs can be used as an alternative to reduce antibiotic resistance in aquaculture.