• Journal of Microbiology and Biotechnology
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• 제13권1호
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• pp.119-124
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• 2003

This study was conducted to evaluate the practical usefulness of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PACE) fingerprinting of whole cell proteins far the identification of lactic acid bacteria in Kimchi. SDS- PACE of whole cell proteins of the reference strains and lactic acid bacteria isolated from Kimchi yielded differential banding patterns that were highly specific fingerprints, thus making it possible to identify. Identification of the isolates from Kimchi was achieved by comparing the SDS-PAGE fingerprints of isolates to those of reference strains. In addition, the reliability of SDS-PAGE was examined by comparing the results with those of the APL 50 CHL system assay and 16S rRNA gene sequence. SDS-PACE assay showed a different identity to reference strains, while the APL 50 CHL system and 16S rRNA gene sequence could not distinguish a few strains. Therefore, SDS-PAGE of the whole cell proteins is a specific and a reliable method that will be useful for the identification of lactic acid bacteria in Kimchi to the species level, and can be used as an alternative or complementary identification method.

• Quantitative Bio-Science
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• 제37권2호
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• pp.125-132
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• 2018

In this study, noble strains of lactic acid bacteria were isolated and identified by genetic analysis of 16s rRNA. Also, pH-dependent growth curve, cholesterol assimilation ability and sugar production efficiency were measured. Lactic acid bacteria were identified to inhabit in the milks from various animals. Results of sequence analysis showed that there were differences in 16S rRNA sequence among strains and part of gene deletion was also recognized. Growth rates were varied, too, depending on the pH of the medium. Lactobacillus rhamnosus LOCK908 isolated from cow milk showed the highest growth rate and high cholesterol assimilation ability. Results of sugar fermentation tests were relatively consistent with the sequencing results. So, we propose newly isolated Lactobacillus rhamnosus LOCK908 as useful candidate for a starter of fermented beverage and probiotics. Results of this study will contribute to the isolation and identification of noble Lactic acid bacteria and to the public health.

• 한국식품영양과학회지
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• 제21권6호
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• pp.681-685
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• 1992

돼지고기에서 분리한 bacteriocin 생성능이 우수한 젖산균을 동정하기 위하여 이미 알려진 몇가지 젖산균을 참고균으로 하여 10% denaturing polyacrylamide gel에 전기영동으로 전개한 5S rRNA 와 tRNA 등 150개 이하의 핵산으로 구성된 저분자량 RNA(Low Molecular Weight RNA : LMW RNA) profiles에 나타난 15~25개의 밴드 양상이 균에 따라 차이점을 보여 동정에 효과적으로 이용할 수 있었다. 새로 분리한 젖산균은 참고균과는 다른 균종이었다. APT, TSB, MRS의 3종류 다른 배지에서 배양하여도 LMW RNA profiles에는 차이가 없었으며, 겔상의 밴드 전개거리를 3개의 표준 분자량 물질을 이용하여 만든 표준곡선을 사용하여 상대핵산단위(relative nucleotide units : RNU)로 나타낸 밴드의 양상을 도표화 하는 것이 profiles를 서로 비교 하는데 편리하였다.

• KSBB Journal
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• 제15권4호
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• pp.359-365
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• 2000

Three lactic acid bacteria (C-1 K-3 and T-1 strain) were isolated from Nuruk and characterized subsequently. They were useful strains for production of lactic acid and their growth was inhibited at 10% ethanol pH 4 These strains were identified as lactococcus lactis subsp. lactis NR C-1 Leuconostoc mesenteroides subsp. mesenterides NR K-3 and pediococcus pentosaceus NR T-1 respectively by morphological physiological and biochemical characterization Lac lactis subsp lactis NR C-1 showed the highest lactic acid productivity. Leu measenteroides subsp mesenteroides NR K-3 showed stable lactic acid productivity and its growth was inhibited at pH 4. P pentosaceus NR T-1 had lower lactic acid productivity than the other two bacteria but it could not grow at 10% ethanol pH 4 The lactic acid productivity of these three strains in MRS broth were higher than that in Skim milk media the optimum pH and temperature for the lactic acid production of the three strains were 30-32$^{\circ}C$ and pH 6.0∼6.8 Glucose was the optimal carbon souorce for the lactic acid production. In terms of antagonism lac lactis subsp lactis NR c-1 showed somewhat inhibitory efects against some Gram positive rod and cocci such as Lactobacillus brevis and Streptococcus mitis. And Leu mesenteroides subsp mesenteroides NR K-3 showed the inhibitory effects against Streptococcus mitis but P. pentosaceus NR T-1 didn't show any inhibitory effects against tested strains.

• Journal of Microbiology
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• 제35권1호
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• pp.10-14
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• 1997

The database of metabolic fingerprints generated using the GIolog system of lactic acid bacteria isolated from kimchi, described by Lee et al. (8), was used for the identification of 75 Leuconostoc isolates. The test strains were isoalted using a selective isolation medium specific for the genus Leuconostoc and examined for their ability to oxidize carbon sources using the Biolog system. The results show that the 75 test strains were identified to the known Leuconostoce clusters. It is suggested that the Biolog system can be applied for rapid identification of lactic acid bacteria isolated from kimchi.

• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.423-428
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• 2000

Bacteriocins are classified as proteins which are produced by heterogeneous groups of bacteria, having and antimicrobial effect of the closely related organisms. Recently, bacteriocins derived from lactic acid bacteria and other food-related organisms have been the subject of much research on potential food biopreservatives. The goal of this study was to screen and characterize the bacteriocinogenic lactic acid bacteria from Jeot-gal(commercial fermented fish foods). All bacteriocinogenic isolates were identified as lactic acid bacteria. Isolates NK24, NK34, and SA72 were tentatively identified as Lactobacillus brevis, according to the API 50 CHL kit database. All antimicrobial substances produced from four lactic acid bacteria isolates completely lost their antibacterial activity after being treated with some proteases, indicating to their proteinaceous nature. The bacteriocin produced from isolates NK24, NK34, and SA72 showed a broad spectrum of activity when compared to those produced from isolate SA131. All bacteriocins isolated during the course of this study showed a bactericidal mode of inhibition.

• 한국식품영양학회지
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• 제17권1호
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• pp.72-79
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• 2004

멸치젓갈로부터 ν-aminobutyric acid(GABA)을 생성하는 유산균주를 분리 동정하였다. 멸치젓갈로부터 분리한 9종의 유산균 중 GABA 생산능이 우수한 균주를 순수 분리하여 형태학적 특성과 gram positive identification(GPI) card 와 API 50kit로 동정한 결과 Lactobacillus brevis BH-21, Lactobacillus rhamnosus BH-28 및 Lactobacillus plantarum BH-38로 동정하였다. 이들 Lactobacillus 속 균주중 Lactobacillus brevis BH-21이 GABA생성능력이 제일 우수하였고, GABA 생성함량은 배지(0.1% glucose, 0.1% yeast extracts, 0.05% polypeptone, 0.002 % MgSO$_4$$.$4$H_2O$, 0.001% FeSO$_4$$.$7$H_2O$, 0.01% NaCl, 0.1% monosodium glutamate, pH 6.0)에서 Lactobacillus brevis BH-21을 배양하였을 때, 배양 24시간에 43.2mg/mL의 GABA을 생성하였다.

• Journal of Microbiology and Biotechnology
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• 제4권4호
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• pp.305-315
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• 1994

Nineteen strains of bacteriocin-producing lactic acid bacteria were isolated from 432 Kimchi samples, and identified by the comprehensive biochemical and morphological tests verifying their cellular fatty acid composition. Using partially purified bacteriocins from these isolates, their inhibitory activities against other lactic acid bacteria and some pathogens, and sensitivity to enzyme and heat treatments were tested. The isolates were identified as Lactobacillus plantarum (2 strains), L curvatus (2 starins), L brevis (2 strains), Enterococcus faecium (6 strains), Leuconostoc mesenteroides subsp. mesenteroides (1 strain) and Lactobacillus sp. (6 strains). The bacteriocins produced by E. faecium strains provided the broadest spectrum of inhibition, affecting against other Gram-positive bacteria including lactic acid bacteria and health-threatening bacteria such as Clostridium perfringens and Listeria monocytogenes. The bacteriocins of Lactobacillus sp., L plantarum and L brevis strains were capable of inhibiting many strains of the lactic acid bacteria, whereas those of L curvatus and L mesenteroides subsp. mesenteroides strains were only inhibitory to a few strains. Generally, the inhibitory activities of both E. faecium and Lactobacillus sp. strains were greater than those of other producer strains. The bacteriocins from the isolates were sensitive to several proteolytic enzymes, and those of L curvatus and L mesenteroides subsp. mesenteroides were also sensitive to lipase and $\alpha$-amylase as well as to proteolytic enzymes. The bacteriocins from the strains of Lactobacillus sp. and a strain of L. brevis were resistant to autoclaving.

• 한국미생물·생명공학회지
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• 제30권2호
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• pp.129-134
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• 2002

토종닭 소장으로부터 가축 소화기 병원성 유해세균의 분리를 위하여 무작위 선별법과 중층-도말법을 사용하여 총130주의 유산균을 1차 분리하였다. 1차 분리한 130주를 paper disc법을 사용하여 최종적으로 살모넬라 균, 포도상구균, 대장균에 대하여 저해능이 우수한 7주를 분리하였다. 분리 균주의 동정을 위하여 1차로 API CHL kit를 사용하였고, 동정의 정확성을 높이기 위하여 2차로 16S rRNA sequencing 방법을 사용하였다. 그 결과 BD14 균주는 Pediococcus pentosaceus로 동정되었으며 나머지 6주는 Lactobacillus sp.로 동정되어 모두 안전성 있는 유산균임을 확인하였다. 여러 병원균에 가장 항균력이 큰 유산균은 L. pentosus K34이었으며, 이 유산균은 염산과 담즙산에 대한 내성에서도 가장 우수한 균주로 나타났다. 10종의 항생제에 대한 감수성을 조사한 결과 ciprofloxacin에 대하여 모든 균주가 내성을 보였고, BL 균주를 제외하고 모든 균주가 colistin, streptomycin에 대하여 내성을 보였다. 또한 BD14, BD16, K34 균주가 gentamicin에 대한 내성을 보였다.

• 한국미생물·생명공학회지
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• 제31권2호
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• pp.191-196
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• 2003

본 연구는 김치로부터 분리한 젖산균의 다양성과 항균성을 조사하기 위하여 수행되었다. 희석한 김치 국물을 CaCO$_3$가 첨가된 MRS 고체 배지에 도말 한 후, $25^{\circ}C$에서 2일 동안 배양하여 여러 가지 김치로부터 27가지의 젖산균을 분리하였다. 이렇게 분리한 젖산균들을 Bergey 분류법과 BPB 배지를 통한 생화학적인 방법과 16S rDNA PCR을 이용한 분자 생물학적인 방법으로써 분석하였다. 그러나 이들 방법으로 분석한 결과가 일치하지 않은 경우가 많았다. 이들 분리 젖산균은 16S rDNA 부분 염기서열을 결정한 결과 Leuconostoc mesenteriodes(11균주), Leu. carnosum(3균주), Lactobacillus curvatus(8균주), Lac. pentosus(2균주), Weisselia kimchi(1균주), W. cibaria(1균주), Pediococcus pentosaceus(1균주) 등의 것과 각각 매우 유사한 것으로 분석되었다. 이들중 Leu. carnosum은 이전에 김치에서 분리되었다고 보고된 바가 없다. 그리고 이들 김치에서 분리 동정한 균들의 항균작용 활성을 검사 해 본 결과 균주에 따라서 활성의 정도는 다르게 나타났으나 Bacillus subtilis, Escherichia coli, Salmonella enteritidis, S. paratyphica, S. typhi, Staphylococcus aureus, Shigella boydii, S. sonnei 등에 대해 뚜렷한 항균효과를 나타내었다.