• 한국균학회지
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• 제25권4호통권83호
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• pp.340-347
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• 1997

사과와 고추에서 분리된 Colletotrichum gloeosporioides의 색소형성형 및 유성세대형 계통균주들의 배양적 및 분생포자의 특성을 비교하였다. 유성세대 형성 계통들의 균사생장은 감자한천배지와 V-8배지에서 색소형성형계통에 비하여 빨랐다. 사과와 고추에서 분리된 색소형성형계통은 감자한천배지와 V-8배지에서 회백${\sim}$회록색의 균사가 환문을 이루면서 군데 군데에 황색${\sim}$연분홍색의 포자덩어리를 생성하였고 자낭포자세대를 형성하는 것은 없었다. 고추에서 분리된 계통은 사과와 감자한천배지에 한쪽 끝이 좁은 포자를 생성하였으나 V-8배지와 물한천잎배지의 것은 방추형이고 더 작았다. 사과에서 분리된 색소형성계통은 공시된 모든 배지에서 방추형의 분생포자를 생성하였다. 사과와 고추에서 분리된 유성세대 형성 계통들은 원통형의 포자를 형성하였는데 대부분은 양끝이 둥글었으며 감자한천배지와 V-8배지에서는 소흑점이 산재한 회백${\sim}$흑록색의 환문균층을 이루면서 자낭포자세대를 형성하였다.

• 한국균학회지
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• 제39권2호
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• pp.99-104
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• 2011

표고버섯의 육종은 두 개의 다른 모균주에 의한 교배와 버섯생산에 좋은 형질을 지닌 교잡균주의 선발이 요구된다. 본 연구에서는 서로 다른 두 계통의 표고 모균주에서 유래한 단핵균주와 이들 단핵균주간의 교배로부터 만들어진 교잡균주에 대하여 발색반응 배지를 이용하여 세포외 분해효소의 분비능력 정도를 비교하여 생화학적 특성이 우수한 균주를 선발할 가능성에 대하여 조사하였다. 모균주로부터 유래한 단핵균주들 간에 ${\beta}$-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, protease의 분비능력에 차이가 있음을 확인하였다. 교잡균주에 있어서도 단핵균주의 조합에 따라 효소 분비능력이 달라지는 것을 볼 수 있었다. 이에 따라 발색반응배지를 이용한 세포외효소 평가법이 표고의 육종과정 중에 생성되는 교잡균주들의 평가에 활용 할 수 있을 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.579-584
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• 2008

A commercial chromogenic agar medium (DFI) was supplemented with glucose (mDFI) to enhance the specificity of Enterobacter sakazakii (E. sakazakit) detection. Escherichia vulneris (E. vulneris), a putative false-positive strain on the DFI medium, produces ${\alpha}$-glucosidase. The enzyme ${\alpha}$-glucosidase hydrolyzes a substrate, 5-bromo-4-chloro-3-indolyl-${\alpha}$, D-glucopyranoside $(X{\alpha}Glc)$, producing green colonies. E. sakazakii strains produced green colonies on both DFI and mDFI agar, whereas E. vulneris produced green colonies on DFI agar but small white colonies on mDFI agar. E. sakazakii and E. vulneris were also readily differentiated by colony color when the mixed culture of the two strains was plated on mDFI agar and incubated for 24 h at $37^{\circ}C$. The results indicate that the selectivity of the commercial chromogenic agar medium could be improved by a simple supplementation with glucose.

• Mycobiology
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• 제36권1호
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• pp.74-76
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• 2008

To obtain basic information on the biochemical property of basidiospores of shiitake mushroom (Lentinula edodes), the ability of producing extracellular enzyme was assessed using a chromogenic plate-based assay. For the aim, amylase, avicelase, $\beta$-glucosidase, CM-cellulase, pectinase, proteinase, and xylanase were tested against monokaryotic strains generated from forty basidiospores of two different parental dikaryotic strains of shiitake mushroom, Sanjo-101Ho and Sanjo-108Ho. These two parental strains showed different degree of extracellular enzyme activity. No identical patterns of the degree of enzyme activity were observed between monokaryotic strains and parental strains of the two shiitake cultivars. The degree of extracellular enzyme activity also varied among monokaryotic strains of the two shiitake cultivars. Our results showed that dikaryotic parental strains of shiitake mushroom produce monokaryotic basidiospores having very diverse biochemical properties.

• 한국식품위생안전성학회지
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• 제31권3호
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• pp.222-225
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• 2016

식품에서 대장균군을 효율적으로 분리하기 위해 대장균군 선택배지 5종: Chromocult Chromocult coliform agar (Merck), Hicrome coliform agar (Sigma), CHROMagar ECC, Brilliance E.coli/coliform medium (OXOID), endo agar (Merck)을 선별하여 식품 분리 대장균군 83종 및 표준균주 21종에 대해서 민감도와 특이도를 분석한 결과 Chromocult coliform agar와 HICrome coliform agar에서 94%도 민감도가 가장 높았으며, Brilliance E.coli/coliform medium는 93%, CHROMagar ECC는 92%, ENDO agar는 74%의 민감도를 나타냈다. Chromocult coliform agar와 HICrome coliform agar는 대장균군의 회수율도 높았다. 그러므로 Chromocult coliform agar와 HICrome coliform agar는 대장균군을 분리하는데 가장 효율적인 배지로 생각된다.

• Journal of Dairy Science and Biotechnology
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• 제39권1호
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• pp.9-19
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• 2021

Enterobacter sakazakii (Cronobacter spp.) causes meningitis, necrotizing enterocolitis, sepsis, and bacteremia in neonates and children and has a high mortality rate. For rapid E. sakazakii detection, various differential and selective media containing α-glucosidase substrates, such as 5-bromo-4-chloro-3-indolyl-α-D-glucopyranoside (BCIG) or 4-methylumbelliferyl-α-D-glucoside (α-MUG), have been developed as only E. sakazakii exhibits α-glucosidase activity in the genus Enterobacter. However, Escherichia vulneris (family: Enterobacteriaceae) can also utilize α-glucosidase substrates, thereby resulting in false positives. Various iron sources are known to promote the growth of gram-negative bacteria. This study aimed to develop a selective medium containing α-glucosidase substrates for E. sakazakii detection that would eliminate false positives, such as those of E. vulneris, and to determine the role of iron source in the medium. Three previously developed (TPD) media, i.e., Oxoid, OK, and VRBG, and the medium developed in this study, i.e., NGTE, were evaluated using 58 E. sakazakii and 5 non-E. sakazakii strains. Fifty-four E. sakazakii strains appeared as fluorescent or chromogenic colonies on all four media that were assessed. Two strains showed colonies on NGTE medium and not on TPD media. In contrast, the remaining two strains showed colonies on TPD media and not on NGTE medium. None of the non-E. sakazakii strains showed fluorescent or chromogenic colonies on any of the evaluated media except E. vulneris, which showed colonies on TPD media and not on NGTE medium. This study demonstrated that the newly developed NGTE medium was not only equally efficient in promoting the growth of bacterial colonies when compared with the currently available media but also eliminated false positives, such as E. vulneris.

• 한국균학회지
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• 제42권1호
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• pp.86-90
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• 2014

본 연구에서는 양송이 육종에 필요한 기본 정보를 얻고자 다양한 출처의 양송이 이핵균주를 대상으로 생육 및 생화학적 특성을 비교 검정하였다. 시험한 31균주 중 대부분의 균주가 Oatmeal agar에서 MEA나 PDA에서 보다 균사생장이 우수하였다. 7가지 세포외효소 활성 비교에서 양송이 균주는 대체로 ${\beta}$-glucosidase가 가장 뚜렷한 활성을 나타내었으며 protease의 활성은 모든 균주가 지니고 있었다. ${\beta}$-glucosidase 활성은 27개 균주에서 xylanase 활성은 30개 균주에서 나타났다. 이에 반해 avicelase, CM-cellulase, amylase, pectinase 활성은 20균주 이하에서만 나타났다. 본 연구 결과는 국내 양송이 육종을 위한 균주 선발 기준 중 하나로 이용될 수 있을 것이다.

• 한국물환경학회지
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• 제25권3호
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• pp.363-369
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• 2009

We developed the Eco medium for Escherichia coli and total coliforms, which was modified by Violet Red Bile (VRB) medium, and derived the standard curve of exponential phase at $OD_{410}$ by using type strains such as E. coli ATCC11303, Enterobacter cloacae KCTC2361, Klebsiella pneumoniae KCTC2241, and Citrobacter freundii KCTC2359. Also, we used total 93 samples of spring and stream water to compare the detection ability of total coliforms between the method using Eco medium and such as most probable number (MPN), and plate count methods. As a result, the qualitative analysis of E. coli and total coliforms using Eco medium contained ortho-nitrophenyl-$\beta$-galactoside (ONPG) and 4-methylumbelliferyl-$\beta$-D-glucuronide (MUG) was same as those of Korean standard methods (Colilert kit). And the colony forming unit (CFU) detected in Eco medium was similar to those of result from MPN and plate count methods. Moreover, the agreement, sensitivity, and specificity of the developed kit was more than 97.5% in comparison with Colilert kit for 350 samples. Thus, the Eco medium can be used both qualitative and quantitative analysis of E. coli and total coliforms.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1469-1476
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• 2007

Jeot-gal is a traditional Korean fermented seafood and has long been used for seasoning. We isolated 188 strains from shrimp, anchovy, and yellow corvina Jeot-gal, and screened sixteen strains that showed strong fibrinolytic activities on a fibrin plate. Among those strains, the strain that had the largest halo zone was chosen and identified as Bacillus licheniformis by using 16S rDNA sequencing and an API CHB kit. The fibrinolytic activity of Bacillus licheniformis was characterized and designated as bpKJ-31. The active component of bpKJ-31 was identified as a 37 kDa protein, designated bacillopeptidase F, by internal peptide mapping and N-terminal sequencing. The optimum activity of bpKJ-31 was shown at pH 9 and $40^{\circ}C$, with a chromogenic substrate for plasmin. It had high degrading activity for the $B{\beta}$-chain and $A{\alpha}$-chain of fibrin(ogen), and also acted on thrombin, but not skim milk and casein. The amidolytic activity of bpKJ-31 was inhibited by 1 mM phenylmethanesulfonyl fluoride, but 1 mM EDTA did not affect the enzyme activity, indicating that bpKJ-31 is an alkaline serine protease, like a plasmin. The bpKJ-31 showed approximately 14.3% higher fibrinolytic activity than the plasmin. These features of bpKJ-31 make it attractive as a health-promoting biomaterial.

• 한국축산식품학회지
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• 제27권4호
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• pp.496-500
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• 2007

The lactase activities of nine species of lactic acid bacteria were compared using the chromogenic substrate, $o-nitrophenyl-{\beta}-D-galactopyranoside$. Streptococcus thermophilus KACC 91147 had the highest lactase activity among a total of thirty strains of Lactobacillus and S. thermophilus tested, including commercial strains. S. thermophilus KACC 91147 released $0.30{\pm}0.12\;mg/mL$ of galactose in treated milk A ($10^7\;CFU/mL$) and $6.49{\pm}0.38\;mg/mL$ in treated milk B ($10^9\;CFU/mL$ milk) over 2 hours. In milk tolerance tests, the blood glucose level (BGL) of 6 volunteers (2 males and 4 females) clinically diagnosed as lactose intolerant increased 3.0 mg/dl after drinking milk A, but a significant (p<0.05) additional increase of $11.2{\pm}4.18\;mg/dl$ was found after drinking milk B. This result suggests that the addition of S. thermophilus KACC 91147 cells into milk aids the digestion of lactose in milk and ameliorates the symptoms of lactose-intolerant individuals due to the activity of lactase from the lactic streptococci.