• Microbiology and Biotechnology Letters
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• v.24 no.6
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• pp.647-651
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• 1996

The development of an enrichment method for the rapid and effective identification of Salmonella spp. in sewage or food was studied. As a growth factor for Salmonella, 10 mM cyclic adenosine monophosphate (cAMP) in trypticase soy broth with 0.6% yeast extract (TSBYE) increased cell number five-folds and 0.6% yeast extract in selenite broth increased cell number ten-folds of control. Bile salts in selenite broth was tested for the selection of S. enteritidis in a mixture with Staphylococcus aureus, Pseudomonas aeruginosa, Lactobacillus plantarum and Escherichia coli. The latter four strains were effectively inhibited at 0.1% bile salt. A two-step culture method was used to enrich Salmonella spp.; a primary-enrichment and secondary- enrichment culture. At a primary-enrichment step, selenite broth with 0.6% yeast extract and 10 mM cAMP was used, and at a secondary-enrichment step, 0.1% bile salt was additionally used. Culture times of a primary- enrichment and a secondary-enrichment step were 8 hr and 6 hr, respectively. In this procedure, cell number increased from 10$^{0.3}$ to 10$^{8.5}$ with inhibition of other strains within 14 hr. In the case of an initial cell concentrarion as low as 10$^{-2}$ cfu/ml, a cell number increased to 10$^{7}$ cfu/ml by using a 10 hr primary-enrichment and 6 hr secondary-enrichment procedure.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.12
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• pp.973-977
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• 2013

These studies were attempted to investigate the change of microbial community of anode of microbial fuel cell using swine wastewater in the enrichment step with the lapse of time. Microbial fuel cells enriched by a 1 : 1 mixture of anaerobic digestive juices of the sewage treatment plant and livestock wastewater. Enrichment culture step was divided into three stages to indentify the microorganisms. It was separated by each lag phase, exponential phase, and stationary phase. These steps were determined by the change of the current value. The current after enrichment was generated about $0.84{\pm}0.06mA$. We were cut out the different 17 bands in the DGGE fingerprint gel to do sequencing. The bands which the concentration was increasing or newly appearing with the lapse of time were included for this study. In the lag and exponential phase, Clostridium, Rhodocyclaceae, Bacteriodetes, and Uncultured bacterium etc. were detected. There were in the stationary phase Geobacter sp., Rhodocyclaceae, Candidatus, Nitrospira, Flavobactriaceae and uncultured bacterium etc. Geobactor among microorganisms detected in this study is known as the Electrochemically active microorganisms. It may include electrochemically active microorganisms to be considered as electrical activity microorganisms.

• Journal of Gifted/Talented Education
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• v.10 no.2
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• pp.1-23
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• 2000

The Schoolwide Enrichment Model(SEM) is a representative model for the gifted education. As the model seems to be more conceptual in nature, it is hard to respond to the different interests and changing needs of the gifted learners. Also it does not provide specific procedures and prescriptions in teaching-learning processes for the teachers. Therefore, SEM needs to be modified into a Systemic Model that is more flexible and procedural. The paper proposes an Instructional Systems Design(ISD) model for SEM. The Systemic Model for SEM consists of 5 major steps. These are as follows: Planning, Diagnosis, Prescription, Implementation, Evaluation. In Planning step, there is a six-stage procedure for initiating the implementation of the SEM. In Diagnosis step, there are two-phases in identifying students for participation in the SEM and assessing strengths, interests, and talents of the learners and recording in The Total Talent Portfolio(TTP). In Prescription step, Curriculum Compacting is administered as a systematic procedure for modifying thecurriculum for above-average ability students. In Implementation step, Enrichment Learning and Teaching is an instructional strategy designed to promote active engagement in learning for teachers and students. Whenever each step has completed, Evaluation step should be followed. These 5 steps are repetitive, cycling and interactive. That is, each one becomes input for the next step, process for itself, and output for the previous step. Each step is monitored through the process of Review and Revision step. In conclusion, the paper suggests six strengths of the Systemic Model for SEM; The Model (1) provides the specific procedure in teaching-learning process; 92) has interactive relations with each component; (3) can be revised continuously for creation of the most effective system; (4) can be implemented more flexibly; (5) can be developed as an unique system for each school; (6) facilitates communications between teachers and students.

• Korean Journal of Microbiology
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• v.47 no.1
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• pp.87-91
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• 2011

The aim of this study was to compare the performance of conventional culture and real-time PCR for detection of Cronobacter spp. in powdered foods. Infant formula, baby food and Misugaru inoculated with Cronobacter were enriched in distilled water as first enrichment step, followed by incubating in Enterobacteriaceae enrichment (EE) broth as second enrichment step. A loopful of enriched sample was streaked onto Druggan-Forsythe-Iversen agar, followed by incubating at $37^{\circ}C$ for 24 h. One milliliter of the enriched distilled water and EE broth were used in real-time PCR assay. No statistical differences were observed in the number of positive samples between culture method and real-time PCR (p>0.05) in all types of food samples. The number of positives of real-time PCR was higher in the first enrichment media (distilled water) than the second enrichment media (EE broth), though there was no significant difference (p>0.05). It appears that some components of the second enrichment broth, EE broth, inhibit the reaction of real-time PCR. These results show that real-time PCR using a single enrichment with distilled water could be useful as an effective screening method for detection of Cronobacter while saving much time and labor compared to conventional culture method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1787-1792
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• 2011

The object of this study was to compare the performance of commercial enrichment media used for Shigella spp. A total of four enrichment media, Gram negative (GN) broth, Shigella broth (SB), selenite-F (SF) broth, and selenite cystine (SC) broth, were tested. When S. sonnei was inoculated into each enrichment broth at 10 cfu/mL of concentration, the highest growth was observed in Shigella broth. Morganella spp., which was not differentiated in selective agar of Shigella spp. thus can be counted as false positive, did not grow in Shigella broth in enrichment step. When S. sonnei was artificially inoculated into pork, it was mostly recovered through an enrichment process with GN broth and SF broth. However, in the case of beef, S. sonnei was mostly recovered with GN broth but largely failed with Shigella broth. Therefore, enrichment media for Shigella spp. should be selected by considering the food matrix in order to increase the chance of isolating it from foods.

• Korean Journal of Veterinary Research
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• v.45 no.2
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• pp.169-177
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• 2005

We developed the one-step strip based on an immunochromatographic (IC) assay for the rapid detection of Listeria spp. Genus-specific monoclonal antibody to flagella of L. monocytogenes was conjugated with 40 nm colloidal gold particles which were prepared in our laboratory. The specificity of the IC strip was tested with pure cultured bacteria. All strains of the genus of Listeria spp. yielded positive reactions and 12 strains of non-Listeria were negative, resulting in a specificity of 100%. L. monocytogenes was artificially inoculated in raw pork macerated with listeria enrichment broth. And then it was 10-fold diluted from $8.7{\times}10^6$ to 8.7 CFU/ml. L. monocytogenes could be detected at a minimum of $8.7{\times}10^5CFU/ml$ before enrichment, $8.7{\times}10^2CFU/ml$ after primary enrichment and 8.7 CFU/ml after secondary enrichment, respectively. These results indicated that the IC strip exhibited high specificity and sensitivity in the detection of Listeria spp.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.326-333
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• 2020

This study focused on self-effects and spouse-effects that impact marital satisfaction in sex role stereotypes, work-family conflict and work-family enrichment. 95 double-income couples participated in this study, and the paired T-Test and multiple regression analysis were conducted. The result of the study showed that sex role stereotypes, work-family conflict, and work-family enrichment are not significant differences in husband and wife, but a husbands was significantly higher than wife in marital satisfaction. In the next step, we considered variables affecting marital satisfaction, and found a significant difference between husband and wife. Work-family enrichment positively affected the husband's marital satisfaction, while the wife's satisfaction was positively affected by the husband's sex role stereotype and negatively affected by her work-family conflict. This study suggests that marriage enrichment programs, the education of husband and wife, and couple counseling should consider individual effects and spouse effects.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.357-364
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• 2006

The meshfree method is extended by the local partition of unity method to model the cohesive cracks in two dimensional continuum The shape function of a particle whose domain of influence is completely cut by a crack is enriched by the step enrichment function. If the domain of influence contains a crack tip inside, it is enriched by the branch enrichment function without the stress singularity. It is found that this method is more accurate and converges faster than the meshless methods for LEFM cracks based on the visibility concept Several staic and dynamic examples are solved to verify the method.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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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.

• Journal of Dairy Science and Biotechnology
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• v.39 no.3
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• pp.113-120
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• 2021

Although the number of incidences of illness caused by ingestion of the bacterial pathogen Enterobacter sakazakii (Cronobacter spp.) has dramatically declined, there remains a need for a robust isolation method to recover this microbe from powdered infant formula (PIF). The current method described in the FDA's Bacteriological Analytical Manual requires multiple steps, and 3-4+ days for complete analysis of PIF isolated E. sakazakii (Cronobacter spp.). We describe a bacteriological method including a one-step enrichment followed by plating on chromogenic agar for presumptive identification of E. sakazakii (Cronobacter spp.). Suspected colonies are confirmed by either biochemical analyses, or a Real-Time PCR-based assay. Using this method, E. sakazakii (Cronobacter spp.) in PIF can be isolated and identified within one day (24 hours).