• 대한수의학회지
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• 제33권3호
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• pp.393-406
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• 1993

Antibacterial substances produced by Lactobacillus casei subsp. and Streptococcus faecium were examined for its antibacterial effects against some pathogenic bacteria. They were partially purified with ammonium sulfate precipitation, methanol-acetone extraction, G-50 gel filtration and examined its characteristics. When L casei subsp. and Str faecium were cultivated in MRS broth, stationary phase of L casei is until 24 hours and Str faecium is 20 hours. pH change of the cultured medium was both decreased after 12 hours and then constant at pH 4.5~4.6 after 28 hours. MRS broth culture fluids of L casei subsp. and Str faecium appeared the antibacterial effects by the spot-on-the-lawn method against ETEC, Sal pullorum and Sta aureus. Culture filtrates of L casei subsp. and Str faecium also appeared the antibacterial effects by the disc diffusion method. Culture filtrates of L casei sub. rhamnosus 7469 produced 0.032M of lactic acid and 0.01M of acetic acid. Str faecium 27273 also produced 0.027M of lactic acid and 0.01M of acetic acid. Protein concentrations of culture filtrates produced by L casei sub rhamnosus 7469 and Str faecium 27273 was $495{\mu}g/m{\ell}$ and $594{\mu}g/m{\ell}$, respectively. Antibacterial substances which are partially purified by ammonum sulfate precipitation, methanol-acetone extraction and G-50 gel filtration inhibit the growth of ETEC, Sal pullorum and Sta aureus. Characteristics of purified antibacterial substances was examined. Its molecular weight was about 31Kd, stabilized at $100^{\circ}C/20min.$ and some of proteolytic enzyme treatment.

• 한국미생물·생명공학회지
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• 제19권5호
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• pp.429-432
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• 1991

생균제를 제조할 목적으로 유아와 동물의 분변으로부터 내산성, 내담즙성 및 항생물질 내성균주를 분리하였다. 분리균주 중 TK-19 균주는 산에 대하여 강한 내성을 나타내었고, 500$\mu g$/ml의 담즙에서도 생육이 가능하였으며 kanamycin(30 $\mu g$/ml), streptomycin(10 $\mu g$/ml), nicin(50 $\mu g$/ml) 및 tetracycline(10 Mug/ml)에 대하여 내성을 나타내었다. TK-19 균주를 동정한 결과 Streptococcus faecium으로 판단되어 Streptococcus faecium TK-19로 명명하였다.

• 한국식품영양과학회지
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• 제32권5호
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• pp.684-688
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• 2003

L- $\alpha$ -glycerophosphate oxidase(GPO)는 L- $\alpha$-glycero-phosphate를 산화시켜 dihydroxyacetone phosphate와 과산화수소의 생성을 촉매시켜 주는 효소로서 혈중에 존재하는 triglyceride의 양을 측정하는 kit를 개발하는데 이용할 수 있으며 본 연구 결과로 종균을 개발 및 확보하였으며, 이 종균의 사용으로 GPO의 발효공정기술을 확립하였고, 또한 이들 조효소로부터 순수한 효소를 생산할 수 있는 정제공정 기술을 확립하였다. 먼저 ATCC에서 네 가지 균주와 KCTC에서 세 가지 균주, 그리고 본 연구실에서 분리한 Streptococcus faecium $M_{74}$.LC 균주 등 8가지 균주의 성장상태를 비교하고 GPO의 역가를 측정 해 본 결과, 배양액 1 L당 ATCC 19634는 65 units, ATCC 12755는 60 units, S. faecium $M_{74}$. LC는 67 units로 S. faecium $M_{74}$.LC가 제일 높은 역가를 생산하였다. 또한 발효조에서 배지의 양을 3 L로 하여 배양온도는 $37^{\circ}C$, 교반속도는 300 rpm, 통기량은 0.5 L/min, 17시간 배양하였을 때 가장 많은 양의 균체가 생성되었으며, GPO의 생산량도 가장 많았다(256 units/L). 이 때 배지 조성은 glucose 0.1%, glycerol 0.2%, tryptone 1.0%, yeast extract 1.0% 및 $K_2HP0_4$0.5%로 하여 배양하였고 GPO의 정제공정은 염투석 분획과 이온 교환수지 공정으로 대별할 수 있으며, 이온교환수지는 DEAE-cellulose 칼럼을 이용한 정제수율은 약 47%를 얻을수 있었다.

• 한국축산식품학회지
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• 제42권6호
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• pp.1020-1030
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• 2022

The aim of the study was to investigate the effect of bacteriocin-like inhibitory substance (BLIS) from Enterococcus faecium DB1 on cariogenic Streptococcus mutans biofilm. Crystal violet staining, fluorescence, and scanning electron microscopy analyses demonstrated that the BLIS from Enterococcus faecium DB1 (DB1 BLIS) inhibited S. mutans biofilm. When DB1 BLIS was co-incubated with S. mutans, biofilm formation by S. mutans was significantly reduced (p<0.05). DB1 BLIS also destroyed the preformed biofilm of S. mutans. In addition, DB1 BLIS decreased the viability of S. mutans biofilm cells during the development of biofilm formation and in the preformed biofilm. DB1 BLIS significantly decreased the growth of S. mutans planktonic cells. Furthermore, S. mutans biofilm on the surface of saliva-coated hydroxyapatite discs was reduced by DB1 BLIS. Taken together, DB1 BLIS might be useful as a preventive and therapeutic agent against dental caries caused by S. mutans.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권2호
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• pp.137-142
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• 2007

The antibacterial activity of Korean honey bee venom (KBV) was examined against seven major bacterial mastitis pathogens, Enterococcus faecium, Escherichia coli, Methicillin resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Streptococcus intermedius, Streptococcus oralis and Streptococcus uberis isolated from infected mammary quarters of cows. Seven bacterial mastitis pathogens were studied for antibacterial activity of the KBV by disc diffusion assay, minimal inhibitory concentrations (MIC) and bacterial count in milk samples. The KBV showed activity against Ent. faecium, E. coli, MRSA, Staph. aureus, Strep. intermedius. The order of susceptibility of the bacteria against the KBV was Staph. aureus>MRSA>E. coli>Strep. intermedius>Ent. faecium>Strep. oralis>Strep. uberis. The MIC against Staph. aureus, MRSA and E. coli were stronger effect as compared with standard drug. The effect of the KBV ($100{\mu}g\;ml^{-1}$) on the viability of Ent. faecium, E. coli, MRSA, Staph. aureus, Strep. intermedius, Strep. oralis and Strep. uberis in milk differed significantly with each other within 12 h incubation period. The results indicate that KBV has significant antibacterial effects against major bacterial mastitis bacteria, Ent. faecium, E.coli, MRSA, Staph. aureus, Strep. intermedius. Results of the study indicate the potential use of KBV as alternative to antibiotic therapy. Further investigations are needed though to confirm its efficacy and its effects on the animals.

• 미생물학회지
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• 제46권3호
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• pp.291-295
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• 2010

Streptococcus parauberis Z49가 생산하는 새로운 bacteriocin의 특성을 조사하고 수성 이상계를 사용하여 발효배양액에서 효율적으로 추출하였다. Nisin과 유사한 S. parauberis Z49의 bacteriocin은 $121^{\circ}C$에서 15 min 열처리해도 활성이 있었으며, 넓은 범위의 pH (pH 2-12)에서 안정하며, M. luteus, Lactobacillus sp., L. fermentum, E. faecium, L. monocytogenes, and P. fluorescens의 생육을 억제하였다. S. parauberis Z49의 발효배양액에 있는 bacteriocin을 간편하게 분리하기 위한 PEG 600/$Na_2SO_4$ 수성 이상계의 최적조건은 PEG 600 15%, $Na_2SO_4$ 30%, NaCl 8% 이었으며, bacteriocin은 PEG층에서 농축이 되었다.

• 한국미생물·생명공학회지
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• 제13권3호
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• pp.289-296
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• 1985

본 연구는 유산간균 및 유산구균으로부터 plasmid DNA를 신속하고 간편하게 분리하기 위한 방법에 관한 것이다. 세포벽 형성 억제 인자인 glycine을 0.5% 첨가한 TCM 배지에서 유산균을 배양하였고 plasmid DNA는 mutanolysin을 처리한 cells로부터 alkaline-detergent lysis 법으로 분리되었다. 유산간균은 효소 처리 때 mutanolysin의 농도를 30$\mu\textrm{g}$/$m\ell$로 하고 37$^{\circ}C$에서 5-10분간 반응되었을 때 plasmid DNA가 아주 잘 추출되었다. 유산구균의 경우는 그 최적 조건이 조금 달랐다. 본 방법은 L. casei, L. acidophilus, L. helveticus, S. lactis, S. faecalis, S. faecium과 S. cremoris 균주로부터 plasmid DNA를 신속하게 분리하는데 사용할 수 있었다. 본 방법을 이용하여 배양액 $1.5m\ell$로부터 분리된 plasmidsDNA가 gel상에서 쉽게 확인될 수 있었다.

• 한국식품저장유통학회지
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• 제6권4호
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• pp.506-513
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• 1999

유기게르마늄(Ge-132, carboxyethylgermanium)에 의한 22가지 젖산균의 성장 효과를 0.01~10mg/m1의 농도로 첨가된 GPYS 액체배지에서 조사하였다. 시험한 대부분의 젖산균은 고농도의 게르마늄에서도 내성이 있었고, 게르마늄의 농도가 높을수록 성장을 더욱 촉진시키는 효과가 나타났다. 게르마늄이 10mg/m1의 농도로 첨가된 GPYS배지에서 Lactococcus factis, Lc. cremoris, Lc. diacetilactis, Enterococus faecium 및 Streptococcus faecalis는 2배 이상 생육촉진의 효과를 나타내었으나, Leuconostoc mesenteroides와 Pediococcus pentosareus는 저해를 나타내었다. Lc. lactic와 Lc. cremoris의 경우, 배양액의 점도는 게르마늄이 첨가된 GPYS배지에서 급격히 증가되었지만, 장시간 배양에 의해서는 약간 감소되었다. 그러나 Lc. diacetilactis, E. faecium와 S. faecalis의 경우, 게르마늄의 첨가에 의하여 생육은 현저하게 촉진되었지만, 배양중의 점도는 증가되지 않았다.

• 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.

• Natural Product Sciences
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• 제24권4호
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• pp.225-228
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• 2018

By activity-guided fractionation, gliotoxin was isolated as an antibacterial metabolite of the fungus Penicillium decumbens which was derived from the jellyfish Nemopilema nomurai. Gliotoxin was further evaluated for antibacterial activity against several piscine and human MDR (multidrug resistance) pathogens. Gliotoxin showed significant antibacterial activity against Gram-positive piscine pathogens such as Streptococcus iniae FP5228, Streptococcus iniae FP3187, Streptococcus parauberis FP3287, Streptococcus parauberis SPOF3K, S. parauberis KSP28, and Lactococcus garvieae FP5245. Gliotoxin showed strong activity especially against S. parauberis SPOF3K and S. iniae FP5228, which are resistant to oxytetracycline. It is noteworthy that gliotoxin effectively suppressed streptococci which are the major pathogens for piscine infection and mortality in aquaculture industry. Gliotoxin also showed strong antibacterial activity against multidrug- resistant human pathogens (MDR) including Enterococcus faecium 5270 and MRSA (methicillin-resistant Staphylococcus aureus) 3089.