• The Plant Pathology Journal
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• 제30권4호
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• pp.432-436
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• 2014

The soil-borne ascomycete fungus Cylindrocarpon destructans causes ginseng root rot disease and produces various secondary metabolites such as brefeldin A and radicicol. The slow growth of this fungus compared with other plant pathogenic and saprophytic fungi in soil disturbs isolation of this fungus from soil and infected ginseng. In this study, we developed a selective medium for C. destructans using radicicol produced by this fungus. Supplementing 50 mg/L of radicicol to medium inhibited the mycelia growth of other fungi including Botrytis cinerea, Rhizoctonia solani and Alternaria panax, but did not affect the growth of C. destructans. In addition, conidia germination of other fungal species except for C. destructans was inhibited in submerged culture supplemented with radicicol. This medium provides a very efficient tool for isolating C. destructans and also can be used as an enrichment medium for this fungus.

• 한국식품과학회지
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• 제53권6호
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• pp.815-818
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• 2021

The objective of this study was to develop a differential medium with improved selectivity for the isolation of Bacillus cereus. Mannitol egg yolk polymyxin medium supplemented with D-galactose allowed the differentiation of diarrheal- and emetic-type B. cereus through pH monitoring. The pH of the medium decreased significantly when incubating the emetic-type B. cereus, whereas the pH change was not significant when incubating the diarrheal-type. The addition of pH indicators, such as methyl red and phenol red, to the medium allowed visual differentiation between diarrheal- and emetic-type B. cereus. A solid agar medium was also developed by optimizing the concentrations of medium components such as monosaccharides, agar, egg yolk enrichment, pH indicators, and antibiotics. This study indicates the possibility of applying selective media for the differentiation of diarrheal- and emetic-type B. cereus.

• 대한수의학회지
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• 제42권3호
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• pp.327-333
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• 2002

The study was carried out to examine the distribution and survival rate of Listeria monocytogenes (L monocytogenes) from various source of waters using improved isolation method. In comparision of enrichment media for isolation of L monocytogenes from water, the isolation rate and 50% detection limit of the pathogen were higher in UVM modified Listeria enrichment broth (UVM) than Listeria enrichment broth (LEB). On the other hand, when compared the selective media for isolation of the pathogen from water, the isolation rate was highest in culture at Oxford agar followed by Fraser agar, and LEB agar. In order to improve enrichment method, 100 ml of water samples with 0.1 CFU/ml of L monocytogenes was inoculated into 10 ml of UVM concentrated at 10-fold, and incubated for 24 h at $36^{\circ}C$. Isolated frequency of the pathogens in improved enrichment method completely corresponded with common (filter) method. Of a total mumber of 147 water samples from river, lake and sea, the pathogen was isolated from 1 of 39 (2.6%) river water samples and 1 of 75 (1.3%) sea water samples, but no pathogen was isolated from 33 lake water samples. Serotypes of 2 isolates were identified as type 1. L monocytogenes decreased in number from 7.2-7.4 to 4.2-4.7 log CFU/ml for 1 week poststorage (5 and $20^{\circ}C$), but the pathogens were able to be detected in river and sea water until 8 weeks after storage. However, in tap water, L monocytogenes were decreased to undetectable level after 2 weeks of storage.

• Biotechnology and Bioprocess Engineering:BBE
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• 제2권2호
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• pp.105-108
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• 1997

A search was undertaken to screen microorganisms that produce an enzyme capable of deacylating glutary1-7-amincephalosporanic acid to 7-aminocephalosporanic acid in soil samples. The screening was carried out by preparing enrichment cultures containing glutary-7ACA and cephalosporin C as selective carbon sources. A non-${\beta}$-lactam model compound,, glutary-p-nitroanilide, was synthesized as a substrate suitable for the rapid screening of microorganisms isolated from the enrichment cultures. Two isolates exhibiting acylase activity, designated BY7.4 and BY8.1, were identified as strains of Pseudomonas species. Pseudomonas BY8.1 showed higher acylase activity toward G1-7ACA than Pseudomonas BY7.4. Environmental conditions for the optimal acylase activity of Pseudomonas BY8.1 were shown to be pH9 and 30$^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1568-1572
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• 2010

The selective isolation of specific proteins from complex protein mixtures by nanoparticles is reported. Glutathionemodified superparamagnetic nanoparticles were used to purify specific proteins fused with glutathione S-transferase via enzyme-substrate interactions. They demonstrated greatly improved selectivity and efficiency over micron sized capturing beads. The ultra-specific enrichment of target proteins was confirmed by both SDS-PAGE and LC/MS/MS experiments.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3755-3759
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• 2010

A on-line SPE (solid phase extraction)-HPLC preconcentration method was developed for the determination of phenolic compounds at trace levels in environmental water sample. XAD-4 and Dowex 1-X8 were used as sorbent in the on-line SPE-HPLC method for the selective enrichment of nine phenolic compounds, which are included in the priority pollutants list of the US EPA. Also alumina prefiltering considerably reduced the amount of interfering peaks due to humic substances that could accumulated due to the preconcentration step and prevent quantification of polar phenolic compounds in environmental water samples. This method was used to determine the phenolic compounds in tap and river water and superiority to the US EPA 625 method in its enrichment factor, pretreatment time, recoveries, and detection limit. The limits of detection were in the range of $0.3-0.9\;{\mu}g/L$ in tap water sample.

• Animal Bioscience
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• 제34권10호
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• pp.1579-1589
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• 2021

Objective: This study was conducted to generate single stranded DNA oligonucleotides with selective affinity to bovine spermatozoa, assess its binding potential and explore its potential utility in trapping spermatozoa from suspensions. Methods: A combinatorial library of 94 mer long oligonucleotide was used for systematic evolution of ligands by exponential enrichment (SELEX) with bovine spermatozoa. The amplicons from sixth and seventh rounds of SELEX were sequenced, and the reads were clustered employing cluster database at high identity with tolerance (CD-HIT) and FASTAptamer. The enriched nucleotides were predicted for secondary structures by Mfold, motifs by Multiple Em for Motif Elicitation and 5' labelled with biotin/6-FAM to determine the binding potential and binding pattern. Results: We generated 14.1 and 17.7 million reads from sixth and seventh rounds of SELEX respectively to bovine spermatozoa. The CD-HIT clustered 78,098 and 21,196 reads in the top ten clusters and FASTAptamer identified 2,195 and 4,405 unique sequences in the top three clusters from the sixth and seventh rounds, respectively. The identified oligonucleotides formed secondary structures with delta G values between -1.17 to -26.18 kcal/mol indicating varied stability. Confocal imaging with the oligonucleotides from the seventh round revealed different patterns of binding to bovine spermatozoa (fluorescence of the whole head, spot of fluorescence in head and mid- piece and tail). Use of a 5'-biotin tagged oligonucleotide from the sixth round at 100 pmol with 4×10⁶ spermatozoa could trap almost 80% from the suspension. Conclusion: The binding patterns and ability of the identified oligonucleotides confirms successful optimization of the SELEX process and generation of aptamers to bovine spermatozoa. These oligonucleotides provide a quick approach for selective capture of spermatozoa from complex samples. Future SELEX rounds with X- or Y- enriched sperm suspension will be used to generate oligonucleotides that bind to spermatozoa of a specific sex type.

• 한국식품과학회지
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• 제19권3호
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• pp.220-224
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• 1987

기포분리 조작에 영향을 미치는 제요소를 조사하기 위하여 bovine serum albumin과 ovalbumin의 표면과잉을 형성하는 농도범위를 결정하고, BSA용액의 기포분리에서 pH, 온도, 가스유입속도, 염농도 등이 미치는 영향에 대하여 관찰하였다. BSA의 임계마이셀농도인 0.03%에서 용액의 pH가 등전점 4.9부근일때 농축율은 최소치를 나타내나 기포분리액의 부피가 최대가 되어 회수율은 최대치를 가지게 된다. 등전점에서 벗어날수록 기포분리액의 양은 감소하나 농축율은 증가하였다. 기포분리온도가 $20^{\circ}C$ 이상으로 상승하면 농축율은 증가하나 분리액의 양은 급격히 감소하여 회수율이 감소하였다. 가스 유입속도가 커질수록 농축율은 감소하고 분리액의 양은 증가하엿다. $(NH_4)_2SO_4$ 첨가에 따라 농축율은 감소하나 분리액의 양은 이온강도 7에서 최대치를 나타내었다. 소수성이 작은 ovalbumin은 표면과잉을 형성하는 농도범위가 BSA에 비하여 200배 이상 높게 나타났다. 이러한 현상은 단백질의 소수성에 따른 기포분리 농축이 가능함을 시사하고 있다.

• 생명과학회지
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• 제13권4호
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• pp.390-399
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• 2003

본 연구는 경남지역의 해수와 해산물에서 Listeria 속을 분리하여 증균배양방법에 따른 균의 분리율, 선택배지에 따른 균의 분리율, 검체에 따른 균종 별 분리율, 생화학 시험과 분리된 L. monocytogenes에 대하여는 혈청형 시험을 실시하였다. 총 100건의 검체에서 증균배양에 따른 Listeria 속의 분리율은 1일 증균배양에서 L. monocytogenes가 4% (4건), L. innocua가 35%(35건), L. ivanovii가 4%(4건), L. welshimeri가 1%(1건)였고, 7일간 증균배양에서는 L. monocytogenes가 1%(7건), L. innocua가 38%(38건), L. ivanovii가 5%(5건), L. welshimeri가 1%(1건)로 동정되어 1일 증균배양 보다 7일간의 증균배양이 Listeria속의 분리에 휠씬 효과적이었다. 이와 함께 Oxford 선택배지나 LPM 선택 배지를 사용하였을 경우 증균배양과 비교하여 검출율이 조금 낮았다. 검체에 따른 Listeria 속의 분리율은 새우와 가재에서 80%(16/20)로 분리율이 가장 높았으며, 바지락에서 50% (10/20), 해수에서 25%(5/20), 홍합에서 20%(4/20)의 순으로 나타났다. 그리고 Listeria 속의 균종 별 분리율은 L. irnnocua가 38%(38건), L. monocytogenes가 7%(7건), L. ivanovii가 5%(5건), L. welshimeri가 1%(1건)순으로 분리되었다. 각 검체에서 Listeria 속의 균종 별 분리율은 새우에서 L. innocua가 65%(13건), L. monocytogenes가 15%(3건), 가재에서 L. innocua가 70%(14건), L. monocytogenes가 10%(2건), 바지락에서 L. innocua가 45%(9건), L. monocytogenes가 5%(1건), 홍합에서 L. innocua가 10%(2건), L. monocytogenes가 5%(1건), L. welshimeri가 5%(1건), 해수에서 L. ivanovii가 25%(5건)분리되었다. L. monocytogenes로 분리 동정된 7주에 대한 혈청형 분류는 type I이 2주, type IV가 5주로 나타났다.

• 대한금속재료학회지
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• 제46권7호
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• pp.427-436
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• 2008

The effect of dewpoints on annealing behavior and coating characteristics such as wettability and galvannealing kinetics was studied by annealing 0.3wt%Si - 0.1~0.4wt% Mn added interstitial-free high strength steels(IF-HSS). The 0.3wt%Si-0.1wt%Mn steel exhibited good wettability with molten zinc and galvannealing kinetics after annealing when the dewpoint of $H_2-N_2$ mixed gas was above $-20^{\circ}C$. It is shown that the wettability and galvannealing kinetics are directly related to the coverage of the external(surface) oxide formed by selective oxidation during annealing. At $N_2-15%H_2$ annealing atmosphere, the increase of dewpoint results in a gradual transition from external to internal selective oxidation. The decrease of external oxidation of alloying elements with a concurrent increase of their subsurface enrichment in the substrate, showing a larger surface area that was free of oxide particles, contributed to the improved wettability and galvannealing kinetics. On the other hand, the corresponding wettability and galvannealing kinetics were deteriorated with the dewpoints below $-20^{\circ}C$. The continuous oxide layer of network and/or film type was formed on the steel surface, leading to the poor wettability and galvannealing kinetics. It causes a high contact angle between annealed surface and molten zinc and plays an interrupting role in interdiffusion of Zn and Fe during galvannealing process.