• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.484-489
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• 1996

The influence of acetic acid (AA) dips on aerobic plate counts (APC), gram-negative bacterial counts (GNC), pH, and sensory tests of pork hams was studied during storage at 4$^{\circ}C$. Pork hams were treated by dipping in 0.5~3.0%(v/v) AA for 0~3 min. Treatments of 1.0~3.0% AA for 3 min completely (P<0.05) inhibited the GNC for 12 days of storage. Treatments of 3.0% AA for 3 min completely (P<0.05) inhibited the APC for 12 days of storage. Treatments with 1.0~3.0% AA for 0~3 min prolonged the microbiological shelf-life to 12 days of storage. Sensory evaluations of pork hams treated with acetic acid were liked less than the fresh controls due to acidic odor and whitness.

• The Korean Journal of Food And Nutrition
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• v.11 no.3
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• pp.329-333
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• 1998

The effects of 0.5%(v/v) acetic acid (AA), 0.5%(v/v) lactic acid(LA), or 0.5%(v/w) citric acid(CA) on gram-negative bacterial counts (GNC) and aerobic plate counts (APC) in flatfish strips stored at 4$^{\circ}C$ or 1$0^{\circ}C$ were assessed. Treatments of 0.5% AA were completely (P<0.05) inhibited GNC compared to the initial controls for 12 days at 4$^{\circ}C$. Treatments of either LA or CA rapidly increased GNC compared to those of AA after 9 days at 4$^{\circ}C$. Treatments of AA were microbiological acceptable for 6 days at 1$0^{\circ}C$, but those of LA and CA did not lasted. AA treatments were completely (P<0.05) inhibited aerobic spoilage bacteria (APC) compared to the initial controls for 6 days at 4$^{\circ}C$. Treatments containing either 0.5% LA or 0.5% CA were ineffective after 9 days at 4$^{\circ}C$ and 3 days at 1$0^{\circ}C$, respectively. Based on these results, AA treatment was the most effective for suppressing the growth of aerobic spoilage bacteria during storage at both 4 and 1$0^{\circ}C$. Flatfish strips treated with 0.5% AA extended microbiological shelf-life for 12 days at 4$^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.617-624
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• 2019

Dielectric barrier discharge (DBD) plasma is one of the promising next generation non-thermal technologies for food sterilization. The present study investigated the effects of DBD plasma on the reduction of most common food-borne pathogenic bacteria (Staphylococcus aureus, Bacillus cereus, Vibrio parahaemolyticus, Salmonella enterica) and sanitary indicative bacteria (Escherichia coli) in the suspension (initial inoculum of approx. 9 log CFU/mL). The bacterial counts were significantly (P<0.05) reduced with the increase in the treatment time (1-30 min) of DBD plasma in the suspension. The D-values (time for 90% reduction) of DBD plasma by first-order kinetics for S. aureus, B. cereus, V. parahaemolyticus, S. enterica, and E. coli were 17.76, 19.96, 32.89, 21.55, and 15.24 min, respectively (R²>0.90). These results specifically showed that 30 min of DBD plasma treatment in > 90% reduction of seafood-borne pathogenic and sanitary indicative bacteria. This suspension study may provide the basic data for use in seafood processing and distribution.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.258-263
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• 2001

Campylobacter spp. isolated and identified from the raw chicken carcasses in food service, were characterized. Total bacterial counts on the skins of raw chicken were 10$^4$~10$^{6}$ CFU/g and a total of 205 strains were primarily isolated after enrichment culture and selective culture of the sample with candle and microaerophilic chamber method. Among them, twenty eight strains of Gram-negative, catalase-positive and oxidase-positive were further isolated by the determination of biochemical characteristics. Only sixteen strains of them were finally identified as Campylobacter with PCR of pA and pB primers. Nine strains, more than half of them, have grown at 42$^{\circ}C$ and $25^{\circ}C$ and seven strains defined as thermophilic Campylobacter grew not at $25^{\circ}C$, but at 42$^{\circ}C$. Therefore, more careful management of food safety for raw chicken is needed in food service. Particularly, we should concern the raw chicken carcasses with high bacteria contamination, more them 10$^{5}$ CFU/g, which possibly includes Campylobacter spp. grown at low temperature.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1341-1349
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• 2000

The addition of 5% NaCI to standard plate count (SPC) and bromcresol purple (BCP) agar showed the highest viable cell counts for Jeot-kal samples. The use of 15% glycerol as cryoprotectant showed the highest microbial survival rate at both temperatures, $-20^{\circ}C$ and $-170^{\circ}C$, and on both colony count media, SPC and BCP. During the aging, the pH of Bajirak Jogae-Jeot (fermented clam) decreased from 6.8 to 5.0. Crude protein content was 10% for Bajirak Jogae-Jeot and $6{\sim}7%$ for Myeolchi-Jeot (fermented anchovy). Microbial population of Bajirak Jogae-Jeot was $10^9\;CFU/g$ after 4 weeks of aging, but was only $10^{3-5}\;CFU/g$ in the case of Myeolchi-Jeot. The proportion of Gram positive and catalase negative bacteria in Bajirak Jogae-Jeot increased drastically during the 4 weeks of aging, which showed typical lactic bacterial fermentation. After 2 years' storage of Jeot-kal in liquid nitrogen tank, the cell counts of total aerobic or lactic bacteria were decreased, resulting in about 10% survival rate. Microbial floral change of Jeot-kal was also investigated. In the case of Bajirak Jogae-jeot, the ratio of rod to cocci and that of Gram negative to positive increased after liquid nitrogen storage. But, rod to cocci ratio of Myeolchi-jeot decreased after liquid nitrogen storage. The ratio of yeasts decreased in both cases after storage.

• Journal of Korean Academy of Nursing
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• v.19 no.3
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• pp.240-248
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• 1989

The increase in size and numbers of general hospitals in the process of conspicuous development of modem medicine has been accompanied by a serious increase in hospital acquired infections. Hospital aquired infections cause pain and discomfort, may threaten life, adds an economic burden, and delays recovery and return to society. Even though respiratory hospital infection rates resulting for tracheostomy and respiratory inhalation therapy, may be low, they are serious because of their bad prognosis and high mortality rates. This study was designed to assess certain aspects of respiratory infections of patients with a tracheostomy and thus provide baseline data for further research related to preventive or therapeutic nursing interventions. The specific objectives were to determine the incidence of colonization in the trachea, clinical signs, type of colonized bacteria and sensitivity to antibiotics. Data were collected from July 1 to December 10, 1989 at two university Hospital in Seoul. Subjects were 20 patients with a tracheostomy admitted to the Intensive Care Unit or Cerebral Vascular Accident Center. Clinical signs related to respiratory infection were observed using a checklist based on previous study outcomes. Bacterial culture, sensitivity test to antibiotics, WBC counts and chest X-ray were also performed. Cultures were done on the day of tracheostomy, and on the third, fifth and seventh day. Cultures were then done on seventh days after the first colonization. The results were as follows : 1. The incidence of bacteria colonization in a week was 90%(18 patients) 50% (10/20 patients) on the day of tracheostomy, 70%(7/10 patients) on the third day, and 0% on the fifth day, and 33%(1/3 patient) on the seventh day. 3 of 18 patients (16.7%) were colonies of mixed growth isolated. 2. The observed clinical signs related to respiratory infection were high fever 38.9%(7 patients), prulent secretion 16.7%(12 patients) and infiltration seen on chest X-ray 33.3%(6 patients). 3. The total number of types of bacteria isolated among the 18 subjects was 21 ; gram negative 71.4%, gram postive 28.6%. The dominant bacteria type was Staphylococcus aureus(5 cases) for gram(equation omitted) and Pseudomonas aeruginosa(3 cases), Klebsiella (4 cases), Enterobacter(3 cases) for gram (equation omitted). The results of culture on 7th day after the first colonization, 6 cases showed same type of bacteria, 3cases showed different type of bacteria and 1 cases showed no growth. 4. The sensitivity tests to antibiotics showed that Pseudomonas aeruginosa and Staphylococcus were strongly resistant to most kinds of antibiotics, but Klebsiella and the rest of gram negative bacteria were moderately sensitive to antibiotics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.157-165
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• 1975

This experiment was carried out to evaluate the sanitary quality of commercially frozen sea foods. One hundred and sixteen samples in six different items from several refrigeration plant in Busan city were examined from March to December in 1974. In addition, the changes in bacterial density through the process from thawing, round or semifilleted frozen alaska pollack to the finishing as frozen fillet blocks were observed. To evaluate the sanitary quality, sanitary indicative bacteria such as total coliform, fecal coliform, fecal streptococci and enterococci as well as plate counts were determined. From the results, the median value of fecal coliform MPN was 20 per 100 grams of the samples and that of enterococci was 790. The median value of plate counts was $2.2\times10^4$ per gram. The plate counts were not correlated with the number of sanitary indicative bacteria. The results suggest that enterococci could be used advantageously in preference to coliform organisms as indicative bacteria for the evaluation of sanitary quality of frozen sea foods. The plate counts at $20^{\circ}C$ of the samples were 14 times higher than that at $35^{\circ}C$. Geometric mean of total coliform MPN was 310 and that of enterococci was 143. Bacterial density was reduced by fleering. Morethan 50 percent for total coliform MPN and $35^{\circ}C$ plate counts, and about 35 percent for enterococci MPN and $20^{\circ}C$ plate counts were reduced under the contact freezing unit which was generally operated at $-40^{\circ}C$. About fifty-five percent of the samples were negative in fecal coliform test and 10 percent of those were exceeded $1.0\times10^5$ per gram in $35^{\circ}C$ plate counts.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.57-62
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• 2007

Microbiological, pH, and sensory evaluations on pork tender-loins treated with potassium sorbate (PS) during storage at $4^{\circ}C$ were assessed. Treatments of 0.5-2.0% PS for 10 min effectively (P < 0.05) inhibited the growth of aerobic plate counts (APC) and gram-negative bacterial counts (GNC) compared to those of controls for 9 days at $4^{\circ}C$, respectively. Results of this investigation demonstrate that antimicrobial activity on APC and GNC in all treatments enhanced by increasing concentrations of PS during storage at $4^{\circ}C$. pH values of pork tender-loins treated with PS gradually increased by storage of 6 days at $4^{\circ}C$. Sensory data showed that 0.5-1.0% PS treatments were quite close in odor and appearance compared to fresh controls. Results indicated that pork tender-loins treated with 1.0% PS for 10 min could extend shelf-life to 9 days during refrigerated storage at $4^{\circ}C$ without adversely affecting sensory quality.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.149-155
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• 2012

Although bacterial outbreaks from ready-to-eat foods such as sprouts have increased, the information on microbial biocontrol by means of sanitizers is limited. Twenty sprouts of red cabbage, baby radish, alfalfa, and broccoli each were collected from the wholesale markets in Seoul. Ethanol and organic acids including acetic acid, citric acid, and lactic acid were used to control the amount of mesophilic bacteria and Bacillus cereus. Sanitizer mixtures of ethanol and organic acids showed a remarkable reduction of viable counts and, in particular, the sanitizer mixture comprised of 20% ethanol and 1% lactic acid seemed to be best by a reduction of 7~8 log CFU/g on the sprouts after a 10 minute exposure. At the same time, the sanitizer comprised of 20% ethanol and 1% lactic acid showed the same reduction for Escherichia coli, Salmonella typhimurium, B. cereus, Staphylococcus aureus, and Enterococcus faecalis, with more effect toward the Gram-negative bacteria. Sensory evaluation by texture, browning, off-flavour, and overall acceptability seemed better just after treatment when compared to one day after treatment with the sanitizer. Therefore, the sanitizers of ethanol-organic acid might be an effective means to control the bacterial contamination of sprouts in palce of sodium hypochloric acid.

• Journal of Microbiology and Biotechnology
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• v.23 no.4
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• pp.518-526
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• 2013

Gut-derived lipopolysaccharides (LPS) are critical to the development and progression of chronic low-grade inflammation and metabolic diseases. In this study, the effects of probiotics Lactobacillus and Bifidobacterium on gut-derived lipopolysaccharide and inflammatory cytokine concentrations were evaluated using a human colonic microbiota model. Lactobacillus reuteri, L. rhamnosus, L. plantarum, Bifidobacterium animalis, B. bifidum, B. longum, and B. longum subsp. infantis were identified from the literature for their anti-inflammatory potential. Each bacterial culture was administered daily to a human colonic microbiota model during 14 days. Colonic lipopolysaccharides, and Gram-positive and negative bacteria were quantified. RAW 264.7 macrophage cells were stimulated with supernatant from the human colonic microbiota model. Concentrations of TNF-${\alpha}$, IL-$1{\beta}$, and IL-4 cytokines were measured. Lipopolysaccharide concentrations were significantly reduced with the administration of B. bifidum ($-46.45{\pm}5.65%$), L. rhamnosus ($-30.40{\pm}5.08%$), B. longum ($-42.50{\pm}1.28%$), and B. longum subsp. infantis ($-68.85{\pm}5.32%$) (p < 0.05). Cell counts of Gram-negative and positive bacteria were distinctly affected by the probiotic administered. There was a probiotic strain-specific effect on immunomodulatory responses of RAW 264.7 macrophage cells. B. longum subsp. infantis demonstrated higher capacities to reduce TNF-${\alpha}$ concentrations ($-69.41{\pm}2.78%$; p < 0.05) and to increase IL-4 concentrations ($+16.50{\pm}0.59%$; p < 0.05). Colonic lipopolysaccharides were significantly correlated with TNF-${\alpha}$ and IL-$1{\beta}$ concentrations (p < 0.05). These findings suggest that specific probiotic bacteria, such as B. longum subsp. infantis, might decrease colonic lipopolysaccharide concentrations, which might reduce the proinflammatory tone. This study has noteworthy applications in the field of biotherapeutics for the prevention and/or treatment of inflammatory and metabolic diseases.