• 한국미생물·생명공학회지
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• 제23권2호
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• pp.214-219
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• 1995

In fermentation of dairy products, bifidobacteria is used in conjunction with other lactic acid bacteria, such as L. acidophilus, L. bulgaricus and S. thermophilus, rendering the enumeration of bifidobacteria difficult. In order to develop optimum conditions for selective enumeration of bifidobacteria, we examined MIC of several antibiotics against various bifidobacteria and other lactic acid bacteria. The growth of L. acidophilus, L. bulgaricus and S. thermophilus were inhibited by lithium chloride at the concentration of less than 4 mg/ml, whereas growth inhibition of bifidobacteria occurred at concentrations over 6-10 mg/ml. Tetracycline and chloramphenicol were also found to selectively inhibit growth of other lactic acid bacteria at the concentration of 1-3 $\mu$g/ml. Addition of 6 mg/ml lithium chloride, 1 $\mu$g/ml, tetracycline or 3 $\mu$g/ml chloramphenicol to medium was found to be optimal for selective enumeration of bifidobacteria. By using these three inhibitory chemicals in the TPY medium, higher number of bifidobacteria were selectively isolated than with NPNL agar and LP agar.

• 한국미생물·생명공학회지
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• 제22권4호
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• pp.443-445
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• 1994

Eubacterium is one of the predominant bacteria in the human large intestine. currently ES (Eubacterium Selective) medium developed by T. Mitsuoka is commonly used as a selective medium. neomycin sulfate which is one of the selective agents of ES medium inhibited about 50% of the growth of Eubacterium isolated, whereas malidixic acid inhibited only 5% while inhibiting other intestinal bacteria. NES medium which replaced neomycin with nalidixic acid in the ES medium was designed and shown to be better for the isolation and enumeration of Eubacterium sp. than ES medium.

• 한국식품영양과학회지
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• 제25권5호
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• pp.754-760
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• 1996

일반적으로 사용되는 젖산균 선택 배지와 변화시킨 배지 중에 김치 젖산균 분리를 위한 선택배지는 Enterococcus속과 Pediococcus속 선별에 KF Streptococcus 배지가, Lactococcus속 선별에 pH 지시약을 첨가한 M-17배지가, Lnctobacillus속 선별에 m-LBS 배지가, Leuconostoc선별에 PES-3 배지가 우수하였다.

• 한국축산식품학회지
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• 제30권1호
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• pp.154-162
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• 2010

This study was carried out to compare the efficacy and selectivity of TOS and BS media for enumeration of bifidobacteria in commercial fermented milk products. First, bifidobacteria was isolated from 20 fermented milk products, and all isolated bifidobacteria were identified by genomic technology as Bifidobacterium lactis. The two media significantly differed from each other with regard to the recovery of B. lactis, that is, the recovery of this organism was as much as 6 logs lower on BS medium than on TOS. When the concentration of BS solution (mixture of paromomycin sulfate, neomycin, sodium propionate, and lithium chloride) used in BS medium was reduced to 50% (BS50), a relatively high percentage recovery of bifidobacteria from pure cultures was achieved. Susceptibility tests to antibiotics and tests for selective agents for the isolated bifidobacteria and lactic acid bacteria were conducted. The BS solution inhibited some lactic acid bacteria and Bifidobacterium species, while mupirocin (MU) suppressed the growth of all tested lactic acid bacteria but not Bifidobacterium. As compared with BS50 medium, TOS with or without MU showed good bifidobacteria recovery and readily distinguishable colonies; in particular, TOS supplemented with MU had a high selectivity for bifidobacteria. In conclusion, all results suggested that TOS medium with or without MU was found to be suitable for selective enumeration of bifidobacteria from mixed cultures in fermented milk, and better in that capacity than BS medium.

• Food Science and Biotechnology
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• 제15권6호
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• pp.866-870
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• 2006

The maintenance of physiological activity during dilution is very critical for the accurate enumeration of Vibrio spp. in marine samples. We investigated the effect of various diluents on the recovery of Vibrio parahaemolyticus using the direct plate counting and most probable number (MPN) methods. The effects of NaCl (0.85 and 3%) and pH (from 6.6 to 7.4) in diluents based on distilled water or phosphate buffered saline (PBS) were evaluated with three V. parahaemolyticus strains. PBS-3% NaCl (pH 6.6), as opposed to PBS, was the most effective diluent at maintaining viable cell numbers up to 2 log CFU/g during dilution for direct plate counting using on thiosulfate citrate bile salts sucrose (TCBS) selective agar, as well as minimizing the difference in cell numbers between TCBS and non-selective nutrient agar. It also increased counts of V parahaemolyticus inoculated into oysters relative to PBS (p<0.01), suggesting that PBS-3% NaCl (PH 6.6) can reduce the problem of underestimating V. parhaemolyticus counts using PBS alone.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.302-309
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• 2001

Colony blot hybridization using a VVHP DNA probe derived from the sequence of the hemolysin gene, vvhA, was specific in identifying all V. vulnificus strains, thereby, eliminating the need for any additional phenotypic identification. The colony blot hybridization procedure revealed a sensitivity and broad applicability sufficient for the direct enumeration of V. vulnificus in various natural samples, without the use of enrichment or culturing on selective medis. V. vulnificus was detected in all natural samples collected during August and May at concentrations ranging from $2.1{\times}10^1\;to\;4.0{\times}10^3$ organisms per ml. However, during November and February, when the mean temperatures of the seawater were $12^{\circ}C$ and $5^{\circ}C$, respectively, V. vulnificus was not detected in any natural samples.

• 한국식품과학회지
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• 제26권3호
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• pp.295-299
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• 1994

Bacteroides는 대장의 상재균총 중 가장 많이 존재하는 균이다. 본 연구에서는 Bacteroides를 분리하여 동정하고 이들 균주들에 대하여 BL배지와 EG배지를 기본 배지로 하여 항생제 및 대사저해제에 대한 감수성 조사를 한 결과 vancomycin은 Bacteroides와 대장균 이외의 장내균들의 생육을 저해하는 것으로 나타났다. 성인에서 대장균은 Bacteroides에 비하여 숫적으로 훨씬 적게 존재하기 때문에 vancomycin이 첨가된 VA배지를 선택배지로 조제하여 한국인을 대상으로 기존의 NBGT 선택배지와 비교한 결과 선택성이 거의 동일한 것으로 나타났고 유아의 경우에는 VA배지가 NBGT보다 우수하였다.

• 한국식품과학회지
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• 제26권5호
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• pp.526-531
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• 1994

한국인의 장내 균총 조사를 하던 중 Bifidobacterium 선택배지로 개발된 Mitsuoka의 BS배지에서 상당수의 Bifidobacterium이 사멸되는 것으로 나타났다. 이에 보다 개량된 Bifidobacterium의 선택배지를 조제하기 위하여 한국인들로부터 Bifidobacterium들을 비선택 배지및 기존의 선택배지에서 분리한 뒤 동정하였다. 분리 동정된 균주들에 대하여 항생제와 대사저해제에 대한 감수성 조사 및 특이 기질검사를 하여 선택배지 조제의 기초 자료로 활용하여 Bifidobacterium이 선택적으로 자랄 수 있는 배지로 TP배지를 고안하였다 TP배지는 상용되는 Mitsuoka의 BS배지보다 Bifidobacterium 선택성이 우수하였고 colony 성장속도도 빨랐다.

• 미생물학회지
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• 제45권2호
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• pp.208-214
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• 2009

장류에서 식중독 미생물인 Bacillus cereus의 계수 방법상 문제점을 해결하기 위하여, B. cereus 선택 배지인 mannitol-egg york-polymyxin B (MYP)에서 자란 약 1,500개의 집락들을 형태적 차이에 따라 12종으로 분류하였다. 생화학 특성 및 16S rRNA 유전자의 염기서열 분석 결과 집락 주위로 환을 형성하는 직경 11~16 mm 크기의 집락들은 B. cereus 와 B. cereus subsp. cytotoxis로 동정되었고, 환을 형성하지 않아 B. cereus 계수에 포함시키지 않았던 직경 5 mm 크기의 분홍색 집락은 B. cereus로, 6.5 mm 크기의 이중환을 형성하여 B. cereus로 계수하기가 모호하였던 붉은색 집락은 B. cereus로 동정되었다. 나머지 세 종들은 Enterococcus sp., Brevibacillus sp., B. subtilis로 밝혀졌다. B. cereus로 동정된 9종 모두에서 적어도 한 종류 이상의 B. cereus 독소 유전자들을 함유하고 있었지만 다른 형태들에서는 발견되지 않았다.

• Journal of Microbiology
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• 제39권4호
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• pp.321-325
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• 2001

Baird-Parker agar with egg yolk/tellurite emulsion (BPA) is widely accepted as a medium for the enu-meration of Staphylococcus aureus in foods. Howerver, it is not vompletely selective and colonies of other genera of species could be similar to those of Staphylococcus aureus. Moreover, the strains of Staphylococcus aureus that are lecithinase negatrive could go unnoticed. Both facts could affect the counts. The aim of this study was to dtermine whether the enumeration of the colonies with the typical morphol-ogy of Staphylococcus aureus on BPA is sufficien to quantity this species in poultry meat. Forty chiken carcasses were tested for Staphylococcus aureus by surface plating using BPA, Results indicate that the predictiv value of the morphoogy of the colonies of BPA is 85.71% and 68.42% for typical and atypical colonies of Staphylococcus aureus, respectively. However, Staphylococcus aureus counts (after identification) and counts of typical colonies did not show any significant differences(P>0.05) and are significantly(P<0.001) correlated (r=0.996).These results suggest that , for screening purposes. enumeration of Staphylococcus aureus from poultry meat does not require any identification of stains. resulting in a saving of time and money.