• 생명과학회지
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• 제15권2호
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• pp.279-286
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• 2005

손바닥선인장 추출물은 한의학에서 항염증 작용, 화상, 부종, 소화 불량 등 몇 가지의 생리학적 기능이 확인되었다. 본 연구에서는 손바닥선인장 줄기를 메탄올을 이용하여 추출한 후 그 추출물을 이용하여 항균활성을 확인한 결과 병원균 등 일반 세균에서 항균활성을 확인하였다. 특히, 약제내성균 및 혐기성 균인 여드름 원인균 뿐만 아니라 효모, 곰팡이 등 진균류에서도 항균활성을 나타내어 넓은 항균 스펙트럼을 가지고 있음을 확인할 수 있었다. 또한 열 처리, 저장온도 및 저장기간이 항균활성에 영향을 미치지 않았으므로 온도 및 기간에 안정함을 확인할 수 있었고, 식품 보존제로서의 가능성 확인 시험에서도 기존의 식품 보존제보다 안전성이 있는 항균활성 물질로 평가되었다.

• 한국식품과학회지
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• 제54권2호
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• pp.209-217
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• 2022

본 연구에서는 모유 유래 유산균 E. faecalis BMSE-HMP005의 다제내성 균주에 대한 항균효과 및 probiotics로써 잠재적인 가능성을 확인하였다. E. faecalis BMSE-HMP005는 다제내성 균주 20주(Enterococcus spp., Staphylococcus spp., Escherichia spp., Pseudomonas spp., Salmonella spp., Klebsiella spp., Enterobacter spp.)에서 모두 MBC가 확인되어 다제내성 균주에 대한 우수한 항균효과를 입증하였다. 또한 RP-HPLC를 이용하여 배양액 내 bacteriocin을 확인하였으며, 이에 대한 분획은 gram 양성 및 gram 음성균주에서 모두 항균력이 나타나, E. faecalis BMSE-HMP005가 생산하는 bacteriocin의 광범위한 항균 스펙트럼을 입증하였다. E. faecalis BMSE-HMP005는 발암 화합물을 유발하는 β-glucuronidase에 대한 활성과 용혈성은 나타나지 않아 안전한 것으로 판단된다. E. faecalis BMSE-HMP005는 vancomycin에 대해서는 내성을 보이나, kanamycin (>0.058), ampicillin (>0.002), erythromycin (>0.002)은 EFSA 기준의 허용범위보다 낮은 MIC가 확인되었다. 또한 인공위액(pH 2.0) 및 인공 담즙산(0.3% bile acid) 조건에서 각각 98.67%, 95.70%의 생존율을 보였다. 이와 같은 결과는 본 연구에서 분리한 모유 유래 유산균 E. faecalis BMSE-HMP005가 다제내성 균주에 대한 우수한 항균활성을 갖는 probiotics로써 잠재적인 가능성을 보여준다. 따라서 건강기능식품의 기준 및 규격에 제시된 바와 같이 Enterococcus spp.는 항생제 내성 및 독성 유전자가 없는 경우에 한하여 probiotics로 사용이 가능한 고시하고 있어 E. faecalis BMSE-HMP005의 안전성에 대한 추가적인 검증이 필요할 것으로 판단된다.

• Archives of Pharmacal Research
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• 제26권8호
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• pp.638-643
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• 2003

Raw milk samples, and cow and chicken intestines were tested to isolate vancomycin-resistant, gram-positive bacteria. From these samples, we isolated seven vancomycin-resistant Streptococcus equinus, two vancomycin-resistant viridans Streptococcus and two vancomycin-resistant Enterococcus faecium. The MICs of several antibiotics, including vancomycin, against these strains were tested. Seven isolates of S. equinus showed high level resistance to vancomycin and teicoplanin (＞100 $\mu$ g/mL). The cell wall thickness of these strains was compared with that of the sensitive strain by TEM and no differences were obserbed between these strains. We compared the strains of vancomycin-resistant Streptococcus equinus using PCR with Microbial Uniprimer Kit. We concluded that it is necessary to combine other methods in order to cluster and identify all isolates of S. equinus.

• Journal of Microbiology and Biotechnology
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• 제25권9호
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• pp.1510-1518
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• 2015

In this work, we wanted to develop a probiotic from famous longevity villages in Korea. We visited eight longevity villages in Korea to collect fecal samples from healthy adults who were aged above 80 years and had regular bowel movements, and isolated lactic-acid-producing bacteria from the samples. Isolated colonies that appeared on MRS agar containing bromophenol blue were identified by means of 16S rRNA sequencing, and 102 of the isolates were identified as lactic-acid-producing bacteria (18 species). Lactobacillus fermentum was the most frequently found species. Eight isolates were selected on the basis of their ability to inhibit the growth of six intestinal pathogens (Escherichia coli O157:H7, Salmonella enterica subsp. enterica Typhimurium, Salmonella enterica subsp. enterica Enteritidis, Enterococcus faecalis, Staphylococcus aureus, and Listeria monocytogenes) and their susceptibility to 15 antimicrobial agents. Among these eight isolates, four Lactobacillus fermentum isolates were found not to produce any harmful enzymes or metabolites. Among them, Lactobacillus fermentum isolate no. 24 showed the strongest binding to intestinal epithelial cells, the highest immune-enhancing activity, anti-inflammation activity, and anti-oxidation activity as well as the highest survival rates in the presence of artificial gastric juice and bile solution. This isolate, designated Lactobacillus fermentum PL9988, has all the characteristics for a good probiotic.

• 미생물학회지
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• 제40권1호
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• pp.17-22
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• 2004

항생제 내성균들의 등장으로 새로운 항생제의 개발이 요구되고 있으나 항생제의 개발은 많은 시간과 인력과 개발비를 필요로 한다. 이 문제를 해결하기 위한 방법의 하나로 전통적으로 감염질환의 치료에 사용되어온 식물인 황금과 황백 추출물의 methicillin-resistant Staphylococcus aureus(MRSA)에 대한 항균활성 보유 여부를 조사하였다. 황금의 메탄올 추출물은 MRSA와 Candida에 대하여 높은 항균 활성을 나타내었으며 황백 추출물보다 활성이 높아 앞으로 새로운 항균제로의 개발 및 사용 가능성이 있을 것으로 보여진다.

• 디지털융복합연구
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• 제13권12호
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• pp.313-318
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• 2015

본 연구에서는 세균의 항균제 내성기전을 연구하기 위해 일개의 대학병원에서 분리된 Enterobacter cloacae를 대상으로 extended spectrum ${\beta}$-lactamase (ESBL) 및 16S rRNA methyltransferase 유전자를 검출하고 항균제 감수성 양상을 조사하였다. 대상균주 중 총 8 균주가 CTX-M-15형 ESBL을 생성하는 것으로 확인되었으며 이 균주들 중 3 균주는 16S rRNA methyltransferase의 한 종류인 armA 유전자도 동시에 가지고 있는 것으로 나타났다. CTX-M-15형 ESBL 유전자와 armA 유전자를 동시에 가지고 있는 E. cloacae는 3세대 cephalosporin 계열 및 aminoglycoside 계열의 항균제 뿐 만 아니라 fluoroquinolone 계열의 항균제에도 내성을 보였다. 더구나 이러한 항균제 내성 유전자들은 플라스미드를 통해 다른 세균으로 전달 될 수 있어 다제내성 세균의 출현 및 확산을 촉진 할 수 있다. 따라서 E. cloacae를 대상으로 지속적인 항균제 내성 유전자를 모니터링 하는 것은 항균제 내성 확산방지를 위해 중요할 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제31권9호
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• pp.1288-1294
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• 2021

There are a growing number of reports of hospital-acquired infections caused by pathogenic bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA). Many plant products are now being used as a natural means of exploring antimicrobial agents against different types of human pathogenic bacteria. In this research, we sought to isolate and identify an active molecule from Sedum takesimense that has possible antibacterial activity against various clinical isolates of MRSA. NMR analysis revealed that the structure of the HPLC-purified compound was 1,2,4,6-tetra-O-galloyl-glucose. The minimum inhibitory concentration (MIC) of different extract fractions against numerous pathogenic bacteria was determined, and the actively purified compound has potent antibacterial activity against multidrug-resistant pathogenic bacteria, i.e., MRSA and its clinical isolates. In addition, the combination of the active compound and β-lactam antibiotics (e.g., oxacillin) demonstrated synergistic action against MRSA, with a fractional inhibitory concentration (FIC) index of 0.281. The current research revealed an alternative approach to combating pathogenesis caused by multi-drug resistant bacteria using plant materials. Furthermore, using a combination approach in which the active plant-derived compound is combined with antibiotics has proved to be a successful way of destroying pathogens synergistically.

• Archives of Pharmacal Research
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• 제6권1호
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• pp.93-102
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• 1983

Waksman's group discovered SM in 1944, and opened a new field of antibiotcs: i. e. AGs. A large group of antibiotics containing aminosugar and/or aminocyclitol is called the AGs. A majority of AGs are produced by actinomycetes. In the first period, AGs effective against tuberculosis were chiefly examined. Following the studies on NM and KM, AGs active against staphyllococci and gram-negative robs were investigated. The discovery of GM and synthesis of DKB and AMK led to the studies on the third generation AGs, which show a broad antimicrobial spectrum including Pseudomonas aeruginosa and drug-resistant bacteria. Since opportunistic infection caused by drug-resistant bacteria are increasing, the third generation AGs are extensively investigated at present.

• 한국수산과학회지
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• 제46권5호
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• pp.528-533
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• 2013

This study evaluated the impact of antimicrobial resistant bacteria produced by inland pollution sources on coastal areas, and investigates antimicrobial resistance profiles of bacteria isolated from marine filter feeders. A total of 107 shellfish (short-necked clams Ruditapes philippinarum, ark shells Scapharca broughtonii, and oysters Crassostrea gigas) were collected from the southern coast of Korea, from which 204 Escherichia coli strains were isolated. The antimicrobial susceptibility patterns of isolated strains were analyzed for 15 antimicrobial agents used in Korea for clinical or veterinary therapy. Antimicrobial resistance was present in 44.6% of E. coli isolates against at least one antimicrobial agent. The rate of antimicrobial resistance in the Narodo area was higher than isolates from the Gangjinman area and Kamak Bay. E. coli isolates had a higher rate of resistance against: tetracycline (29.9%), streptomycin (25.5%), and trimethoprim (14.2%). Of 204 isolates, 29 (14.2%) were resistant to multiple antimicrobial agents.

• 대한의생명과학회지
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• 제20권2호
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• pp.77-84
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• 2014

Periodic analysis of local epidemiologic data of prevalent pathogens of blood culture can provide clinicians with relevant information to guide empirical antibiotic therapy. In this study, we analyzed a pattern of change of causative microorganisms and antimicrobial resistance at a tertiary medical center in Chungcheong province from 2003 to 2012, retrospectively. Of 70,258 blood specimens cultured, 6,063 (8.6%) were positive. Among the positive isolates, 95.9% were aerobic or facultative anaerobic bacteria, 0.1% were anaerobes, and 3.9% were fungi. Coagulase-negative Staphylococci (CoNS) (32.9%), Escherichia coli (16.7%), Staphylococcus aureus (9.1%), Klebsiella pneumoniae (6.4%), and ${\alpha}$-hemolytic Streptococcus (5.9%) were commonly isolated bacteria, and Candida albicans (1.4%) was the most commonly isolated fungi. Enterococcus faecium progressively increased but Streptococcus pneumoniae, Acinetobacter baumannii and Proteus species gradually decreased over a period of 10 years. The multidrug-resistant microorganisms such as methicillin-resistant S. aureus (MRSA), vancomycin-resistant enterococci (VRE), cefotaxime-resistant E. coli, imipenem-resistant Pseudomonas aeruginosa (IRPA) and imipenem-resistant A. baumannii (IRAB), were significantly increased. Therefore, there is a need for a more strict control of antibiotics and a more updated guideline for the treatment of bloodstream infection.