• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.238-242
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• 2009

Pediococci selective medium (PSM) supplemented with ampicillin (A) reported as valid for the detection and enumeration of pediococci included in foods and animal feed was evaluated for the selective detection of the genus Pediococcus in kimchi. PSM is based on the complex basal medium MRS supplemented with cysteine hydrochloride, vancomycin, novobiocin, and nystatin. In the medium evaluation with known species, the growth inhibition of leuconostocs, Pediococcus pentosaceus, Lactobacillus casei, Lactobacillus curvatus, Oenococcus oeni, and Streptococcus thermophilus was not confirmed. In the application of kimchi samples on the selective medium, leuconostocs, P. pentosaceus, Weissella koreensis, Lb. curvatus, Lactobacillus brevis, and Lactobacillus sakei were detected. PSM+A was proved to be not applicable for the detection of pediococci in kimchi.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.309-315
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• 2019

To enumerate Staphylococcus aureus in food, Baird-Parker Agar (BPA) is usually used in the conventional method, However it requires time and space for the preparation and plating, and incubation. Thus, use of the $3M^{TM}$ $Petrifilm^{TM}$ Staph Express Count Plate (STX Petrifilm) might be appropriate to solve these challenging problems. The purpose of this study was to compare the efficiency of STX Petrifilm with BPA for enumeration of S. aureus in various foods. A mixture of S. aureus strains ATCC29213, ATCC25923, and ATCC13565 was inoculated on marinated pork chop, beef (chuck tender), dried filefish, semi-dried squid, rice cake, and Japchae (stir-fried glass noodles) at 2, 3, 5, and 7 Log CFU/g. S. aureus cell counts were enumerated by spread-plating on STX Petrifilm and BPA after 0 and 24 hours at $4^{\circ}C$ (marinated pork chop, beef, semi-dried squid, and stir-fried glass noodles) and $25^{\circ}C$ (dried filefish and rice cake). Recovery of STX Petrifilm for S. aureus from various food samples was compared with BPA, and the results showed that there were no significant differences between two selective media in all cases. The results indicated that STX Petrifilm had enough efficiency to recover S. aureus from various foods as well as saving time and space.

• The Journal of the Korean Society for Microbiology
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• v.11 no.1
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• pp.33-48
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• 1976

The practical significance of using a selective enrichment procedure for detecion and enumeration of salmonella is well recognized. There are still various selective enrichment media has been communly used. Early years selenite broth was recomnended as an enrichment media for the isolating of salmonella. Hajna introduced a modified tetrathionate broth and demonstrated the greater efficiency to compare with the previous enrichment media. Raj also described that the new medium called dulcitol selenite enrichment and has been found to be very satisfactory, especially general implication in food poisoning. Authors tried to compare these 3 enrichment media for isolating salmonella. 1. When salmonella strains were inoculated $1{\sim}10^6$ cells per tube to these 3 enrichment media, mostly similar results were obtained between selenite broth and DS broth. In these 2 enrichment broth were showed $10^7/ml-10^8/ml$ cells of all tested salmonella strains. But in the case of TT broth it was found that the growth was $10^3/ml{\sim}10^4/ml$ cells for tested strain. 2. When E. coli, Proteus, Citrobacter were inoculate $10{\sim}10^6$ cells per tube to these 3 enrichment media. It was suggested that DS broth was showed more inhibitory action than that of selenite broth. TT broth showed high inhibition to these 3 organisms tested. 3. It was generally known that the incubation time is influenced to the frequency of salmonella detection. For this tendency, DS broth and selenite broth were showed similar results within 24 hrs to 48hrs incubation to the test. But DS broth showed more inhibitory action to E. coli and Proteus than that of selenite broth. 4. When $1{\sim}10$ cells were inoculated(per tube) to these 3 enrichment media, DS broth was found to be more sensitive than that of selenite broth.

• Journal of Food Hygiene and Safety
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• v.3 no.1
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• pp.19-26
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• 1988

Most of meat spoilage bacteria area Gram negative, which are very sensitive to freezing ; for instance , 90% of E. coli cells are killed or sub-lethally injured by freezing at -3$0^{\circ}C$, and the freeze-injury rate is dependent upon freezing rate. Since the injured bacterial cells are sensitive to selective agents, they fail to multiply in selective media. Injured bacterial cells are, however, capable of spontaneous repair at appropriate environmental and nutritional conditions . Enumeration of injured bacterial cells involves artificial induction of repair at these conditions. Cubic beef samples(3$\times$3$\times$3cm) were frozen at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$. The samples frozen at each temperature were thawed at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave . After these respective freezing an thawing treatments, the percentage of sub-lethally injured total coliforms out of total surviving ones was measured and compared. The results were as follows: 1. The interaction between freezing and thawing on injury rate was not significant. 2. The injury rates(as means of all three thawing treatments post-freezing) by freezing at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$ were 32.2$^{\circ}C$ and 19.2$^{\circ}C$ respectively . 3. The injury rates(as means of all three freezing treatments)by thawing at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave were 49.3%, 11.7% and 21.0% respectively. The highest injury rate was caused by freezing at -6$0^{\circ}C$ and subsequent thawing at 4$^{\circ}C$. However since the injury rates by freezing treatment were not significantly different, freezing at -18$^{\circ}C$ and subsequent thawing at 4$^{\circ}C$ can also be recommended , from an economic perspective.

• Herbal Formula Science
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• v.17 no.2
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• pp.73-83
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• 2009

Objective : In vitro proapoptotic effect of Hangbaek-Tang (HBT) has been documented by one of us. In the present study, we aimed to demonstrate in vivo effect of HBT on tumor growth. Methods : In vitro selective cytotoxicity of HBT was examined by enumeration of viable cell numbers using BC3A mouse leukemic cells and normal spleen cells. In vivo effect of HBT (25 and 50 mg/mouse) on tumor growth was assayed using BC3A cells innoculated subcutaneously in the flank. Annexin-V apoptosis assay and PI staining was performed to determine the effective serum factor in HBT-treated mice. Leukocyte recruitment into peritoneum were analyzed by microscopy with a stained cytosmear of peritoneal lavage fluid. Results : HBT exhibited in vitro selective cytotoxicity to leukemic cells and did not show any toxicity on immune organs. In vivo i.p. administration of HBT induced significant reduction in tumor growth but not complete regression. Sera obtained from HBT-treated mice strongly inhibited BC3A cell growth in vitro and were revealed to markedly enhance apoptosis and accompanying cell death, when compared to those from PBS-treated mice. Abundant extravasation of leukocytes, especially neutrophils, into peritoneum was observed in HBT-treated mice. Conclusions : HBT causes leukemic, BC3A cell death in vivo via apoptosis as well as in vitro, for which functional involvement of leukocytes is suggested.

• Journal of Fashion Business
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• v.16 no.2
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• pp.124-137
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• 2012

This study aims to identify the meaning and formation cause of a style, and the essential elements of style formation, through psychobiological research as well as an analysis of the designs of Iris Van Herpen, a fashion designer, who in just 6 years has developed into a world-renowned new designer. As a result, it has been found that the psychobiological causes to form a style stem from the action of 'long-term memory', which is consolidated by 'selective attention', 'perceptional subjectivity', the principle of the 'neuron's connection specificity and invariance', and the principle of a 'neuronal signal's unilateral flow'. With such action, Herpen could develop her own original composition techniques. The formative shapes created by such composition techniques are characterized by enumeration, superposition, and hanging. The study has also found that the essential elements for a designer to be able to form his/her own style include 'aesthetic originality' in which the designer views the property of a thing from his/her inherent perspective, and finds the uniqueness from the thing that only he/she can express, 'technical differences' that are creative and original, and 'formative specificity' that is summarized into one property through an impressive shape.

• Journal of Food Hygiene and Safety
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• v.27 no.2
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• pp.169-175
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• 2012

Five kinds of selective media, such as mannitol salt agar (MSA), Baird-Parker agar (BPA), Baird-Parker supplemented with rabbit plasma fibrinogen (BPA+RPF), CHROMagar Staphylococcus aureus (CSA), and Petrifilm Staph Express count system (Petrifilm), were compared to recommend the optimum selective media for isolation of Staphylococcus aureus from agricultural products. Seventy four target and non target bacteria were inoculated on five selective media to analyze sensitivity and specificity. In the recovery test of injured S. aureus cells, S. aureus was exposed to acid (1% lactic acid for 10 min), heat ($60^{\circ}C$ for 90s), and cold ($-20^{\circ}C$ for 1h) conditions. And artificially contaminated agricultural products (iceberg lettuce, green pepper, and cherry tomato) was enumerated on five selective media. The sensitivity of BPA+RPF, CSA, Petrifilm, MSA, and BPA were 100%, 100%, 100%, 90.5%, 90.5%, respectively. In addition, the specificity of BPA+RPF, CSA, MSA, BPA and Petrifilm were 100%, 100%, 84.6%, 75.0%, 67.3%, respectively. However, no difference among five selective media was observed in recovery on injured S. aureus cell and enumeration from agricultural products. This results suggest that BPA+RPF and CSA are the optimum media for detection of S. aureus from agricultural products.

• Journal of Microbiology and Biotechnology
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• v.20 no.1
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• pp.153-160
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• 2010

The present study was carried out for the isolation of bacteriocin-producing enterococci from indigenous sources. Gram-positive enterococci are known for having the ability to produce enterocins with good antimicrobial potential. A total of 34 strains were isolated from processed dairy products of Pakistan and seven out of them were found to be member of genus Enterococcus on selective enumeration. Biochemical and molecular characterization revealed that four of these isolates (IJ-03, IJ-07, IJ-11, and IJ-12) were Enterococcus faecalis and three (IJ-06, IJ-21, and IJ-31) were Enterococcus faecium. Local processed cheese was the source of all enterococcal isolates, except E. faecium IJ-21 and IJ-31, which were isolated from indigenous yoghurt and butter samples, respectively. Bacterial isolates were sensitive to commonly used antibiotics except methicillin and kanamycin. They also lacked critical virulence determinants, mainly cytolysin (cyl), gelatinase (gel), enterococcal surface protein (esp), and vancomycin resistance (vanA and vanB). Polymerase chain reaction amplification identified that enterocin A and P genes were present in the genome of E. faecium IJ-06 and IJ-21, whereas the E. faecium IJ-31 genome showed only enterocin P genes. No amplification was observed for genes that corresponded with the enterocins 31, AS-48, L50A, and L50B, and ent 1071A and 1071B. There were no signals of amplification found for E. faecalis IJ-11, indicating that the antimicrobial activity was because of an enterocin different from those checked by PCR. Hence, the indigenous bacterial isolates have great potential for bacteriocin production and they had antibacterial activity against a variety of closely related species.

• Nuclear Engineering and Technology
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• v.1 no.1
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• pp.17-22
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• 1969

English sole (Parophrvs vetulus) fillets packaged in polymylar bags were irradiated at 500 Krad, using a Cobalt-60 irradiator and the accumulation of spoilage indices substances and bacterial growth in the irradiated and unirradiated samples were measured during 36 days of storage at 0-2$^{\circ}C$. A casein agar plate technique was developed for a direct enumeration of proteolytic bacterial population, thus enabling the determination of relative proportion of proteolytic bacteria in the total microflora at each storage interval. Irradiation at 500 Krad resulted in a ten fold reduction of microflora and throughout the storage period the level of microflora lagged behind that of the unirradiated, by as much as one thousand fold. This was accompanied by a remarkable suppression of TVB and TMA accumulation in the irradiated, never reaching a spoliage level. Proteolytic bacterial population also was reduced to below one per cent of the total viable count and remained so throughout the storage period, while proteolytic bacteria in the unirradiated increased proportionately with the storage, comprising 85.5% of the total microflora by the twenty-second day. This selective removal of proteolytic bacteria must account for the reduced rate of proteolysis occurred in the irradiated during the storage.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.751-756
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• 1999

The inhibitory effect of antibiotics on growth of lactobacillus, streptococcus and bifidobacteria was examined to develop the selective media to isolate and enumerate bifidobacteria from the fermented foods containing various lactic bacteria. The growth of lactic bacteria was inhibited seriously but that of bifidobacteria was not inhibited by gentamycin or ripampicin at the concentration of more than $100\;{\mu}g/mL$. However lactic bacteria did not grow in MRS broth containing $50\;{\mu}g/mL$ of ampicillin and the growth inhibition of bifidobacteria occurred. The growth inhibition of bifidobacteria was more severe than lactic bacteria in $100\;{\mu}g/mL$ of fosfomycin. Therefore, the MRS medium containing $80\;{\mu}g/mL$ of neomycin sulfate, $50\;{\mu}g/mL$ of gentamycin, $50\;{\mu}g/mL$ of rifampicin, $15\;{\mu}g/mL$ of nalidixic acid and $3\;{\mu}g/mL$ of lithium chloride was concluded selective for bifidobacteria, but restrictive for the other lactic bacteria present in Kimchi and cheese.