• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2000.04a
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• pp.116-123
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• 2000

The purpose of this work was to investigate the induction of stress shock proteins (SSPs) in Burkholderia sp. YK-2 in response to 2,4-dichlorophenoxyacetic acid (2,4-D), and Pseudomonas sp. DJ-12 to benzoate, 4-chlorobenzoate (4-CBA), 4-hydroxybenzoate, and biphenyl. The SSPs, which contribute to the resistance of the cytotoxic effect of the toxic aromatic compounds including 2,4-D and 4-CBA, were induced at different concentrations of the compounds in exponentially growing cultures of Burkholderia sp. YK-2 or Pseudomonas sp. DJ-12. This response involved the induction of a 43 kDa DnaK and 41 kDa GroEL proteins in Burkholderia sp. YK-2, characterized by SDS-PAGE and Western blot using the anti-DnaK and anti-GroEL monoclonal antibodies. In Pseudomonas sp. DJ-12, 70 kDa DnaK and 60 kDa GroEL proteins was induced as SSPs, respectively. The total SSPs were analyzed by 2-D PAGE. Survival of Burkholderia sp. YK-2 or Pseudomonas sp. DJ-12 with time in the presence of different concentrations of the compounds was monitored, and viable counts paralleled the induction of the SSPs in these strains. Cells treated with the increased concentrations of toxic compounds showed some destructive openings on the cell envelopes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.3
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• pp.293-300
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• 2015

We sought to extend the shelf-life of Alaska pollack Theragra chalcogramma sikhae while maintaining quality. We compared the chemical, microbiological, and organoleptic characteristics of sikhae prepared under four different conditions. Control fish were fermented at ambient temperature ($21{\pm}2^{\circ}C$); other samples were stored at $5^{\circ}C$ after fermentation at ambient temperature for 36 h (A1), 60 h (A2), and 84 h (A3). Volatile basic nitrogen and amino-nitrogen levels, and total acidity increased with fermentation time in all samples, but the pH fell, attaining a relatively lower level in the control than in other samples. Over 90% of all viable cells were lactic acid-producing bacteria; this proportion did not change significantly during fermentation. In terms of texture, only hardness was affected by fermentation. The hardness of the control fell more rapidly than did that of the other samples. In terms of sensory evaluation (the acceptance test and quantitative descriptive analysis [QDA]), A2 was superior to other samples after fermentation for different times; A2 maintained limited salability (6 points on the relevant index) for up to 17 days of storage.

• Journal of Dairy Science and Biotechnology
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• v.17 no.1
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• pp.58-71
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• 1999

This study was designed to investigate the health promotion effect of fermented milk and historical story of Korean dairy products from the ancient period to present. Although the origin of fermented milk is Europe, the recede of fermented milk was founded in far-east and middle east areas at BC 4C. After the spread of fermented milk to Korea and Japan. The consumption of fermented milk in Korea was dramatically increased to 14.2 kg per person in 1997. Health promotion effect of fermented milk can be devided to 5 major effected improvements of intestinal microflora, anticancer, cholesterol assimilation anti-pathogenic activity. Fermented milk reduced the level of ${\beta}$-glucornidase and nitroreductase to 50% and it provides anticancer activity by cell wall an polysaccharides. Fermented milk has cholesterol assimilation activity ca. 54${\sim}$40% (B. longum, Str. thermophillus). Anti-pathogenic activity of fermented milk was significant. It appeared that Sal. ser. typhimurium was more susceptible than 5. coli 0157 at low pH fermented milk. Viable cells of E. coli 0157 were not dramatically decreased in most of fermented milks tested, but in general, Sal. ser. typhimurium was drastically decreased in most of the fermented milks.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.373-377
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• 1995

We investigated the survival, $\beta$-galactosidase activity and cellular permeability of lactic acid bacteria such as Lactobacillus acidophilus ATCC 4356, Lactobacillus casei subsp. casei IFO 3533, Streptococcus thermophilus KCTC 2185, Lactobacillus delbrueckii subsp. lactis ATCC 4797, and Lactobacillus delbrueckii subsp. bulgaricus ATCC 11842 in anaerobic condition of pH 1.5-3.5 range. Numbers of all tested viable cells did not decrease at pH 3.5, but decreased rapidly at pH 1.5 and pH 2.5 during 2 hour incubation at modified EG medium. Immediately after 2 hour incubation, the decrease in population at pH 1.5 and pH 2.5 was about 6-8 and 5-7 log cycles/ml, respectively. Lactobacillus acidophilus ATCC 4356 showed the higest survival of all tested bacteria. The $\beta$-galactosidase activity from Lactobacillus delbrueckii subsp. bulgaricus ATCC 11842 and Streptococcus thermophilus KCTC 2185 decreased rapidly at pH 1.5 and 2.5, but there was a little decrease at pH 3.5. The cellular permeability that was measured by the leakage of intracellular materials increased with decrease of pH. These results suggest that the ingested lactic acid bacteria may be destroyed in contact with low pH of gastric acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.2
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• pp.259-267
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• 1998

Typical characteristics of Mejus must be understood to get the basic data for setting up mass production system of traditional fermented soybean products. One hundred and twenty one Mejus were collected from various places and analyed. Most of shapes were rectangular and some were spherical, conical, cylindrical and doughnut types. The weight of Mejus was 0.4~4.2kg. Chemical analysis showed: moisture content, 9.73~58.22% ; pH, 4.95~8.15; acidity, 0.6~3.8% ; soluble protein content, 4.45~12.31%; soluble sugar content, 0.82~10.95%. Enzyme assay showed: $\alpha$-amylase activity, 5.0~874.2 units/g; $\beta$-amylase activity, 0.02~27.74units/g; acidic protease activity, 31.3~225.1unts/g; lipase activity 1.0~53.0units/g. Total viable cells were 3.72$\times$107~1.35$\times$1010cfu/g, and yeast and mold count 6.46$\times$104~8.91$\times$106cfu/g. respectively. $\alpha$-Amylase activity of a traditional Meju from Incheon showed the highest activity of 732.8 units/g(interior section) and 823.2units/g (exterior section). $\beta$-Amylase activity was the highest{3.57 units/g (interior sectin) and 4.25units/g (exterior section)} in Meju from Chunbuk. Acidic protease activity was the highest in sample from Seoul, whereas traditional Meju from Kyongnam showed the highest activity of 21.5units/g(interior section) and 37.5units/g(exterior sectin).

• Journal of Korean society of Dental Hygiene
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• v.20 no.3
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• pp.387-397
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• 2020

Objectives: This study aimed to evaluate the inhibitory effects of probiotics containing Lactobacillus reuteri on Streptococcus mutans and Aggregatibacter actinomycetemcomitans. In addition, the degree of biofilm formation, initial acidity, buffering ability, and acid production performance were measured to confirm the dental caries-inducing ability. Methods: S. mutans (KCTC3065) and A. actinomycetemcomitans (KCTC2581) were used as experimental strains. The number of viable cells, degree of biofilm formation, initial pH, buffering capacity, and production performance were measured for comparing L. reuteri-containing probiotics and Bulgaris. Results: The viability of S. mutans in the groups was reduced in the following order: Bulgaris, probiotics, control. The degree of biofilm formation was significantly higher at 0% and gradually reduced at different concentrations (p<0.01). At 2.5%, the absorbance of the probiotics and Bulgaris groups differed significantly (p<0.01). The acid formation ability differed significantly based on the performance of S. mutans in each product (p<0.05). The absorbance of the probiotics group was significantly lower than that of the Bulgaris group (p<0.01). Conclusions: This study suggests that the use of L. reuteri-containing probiotics as an adjuvant for the prevention and decreasing of oral diseases may reduce their incidence, which can be considered one of the benefits of using probiotics.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.125-129
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• 2007

Artemisia capillaris THUNB is a perennial herb that belongs to the family Compositae spp and the most common plant among the various herbal folk remedies used in treatment of abdominal pain, hepatitis, chronic liver disease, jaundice and coughing in Korea. This experiment was conducted to investigate the inhibitory effects of orally administrated Artemisia capillaris extracts on the pathogenic bacteria in 200 ICR mice. The experimental groups showed inhibitory effects on the bacteria in $1{\sim}3$ days after inoculation. After 21 days of inoculation, no viable bacterial cells appeared in the feces of both experimental groups while they did appear in the control group. The results of these studies indicate Artemisia capillaris extract exhibited excellent antimicrobial and inhibitory effects on the food poisoning pathogenic bacteria; S. enteritidis, E. coli O157:H7, L. monocytogenes and S. aureus.

• The Korean Journal of Food And Nutrition
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• v.20 no.3
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• pp.289-294
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• 2007

For the purpose of developing a functional yogurt, a new type of yogurt was prepared. To manufacture this new yogurt, 12% skim milk was added to the hot water extract of black soybeans. The yogurt was then evaluated for its acid production(pH and titratable acidity), number of viable cells, viscosity, quality-retention properties, and sensory properties. The titratable acidity of the yogurt with the added 5% black soybean hot-water extract was higher(2.07%) than that of the yogurt without the added extract(1.80%). The viscosity of the yogurt made by adding 5% black soybean hot-water extract was higher(5,040 cps) than that of the yogurt made with only skim milk(2,740 cps). Lactic acid bacteria propagation was stimulated by the addition of the 5% black soybean hot-water extract. When the yogurt prepared with the black soybean hot-water extract was kept at $7^{\circ}C$ for 14 days, its quality-retention was comparatively good. Finally the overall sensory score of the yogurt made with the added 5% black soybean hot-water extract was slightly lower than that of the yogurt made with only skim milk.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.864-868
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• 1998

The studies were carried out to investigate the mixed effects of medicinal herbs, such as Lithospermum erythrorhizon and Glycyrrhiza uralensis(LG), and LG with chitosan(LGC) on shelf-life of kimchi fermented at 1$0^{\circ}C$ for 25 days. During the fermentation, pH was more slowly lowered in LG(1%, 3%) and LGC treatments than in control. Titratable acidity of these treatments was slightly lower than that of control. Viable cells of total bacteria and lactic acid bacteria in kimchi added with LG(3%) and LGC showed inhibitory effects about 1.2~1.6, 1.3~1.8 log10 cycle. The sour taste of kimchi added with LG or LGC was changed more slowly than that of control during fermentation for 5 days at 1$0^{\circ}C$. But flavor, color and overall acceptability did not show significant differences(p<0.05) among treatments. The color of kimchi added with LG was improved significantly by adding of 1% chitosan. The shelf-life of kimchi added with LGC was extended about 10 days than control.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.236-239
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• 2004

Microbial contamination of ready-to-eat ingredients for Kimbab manufacturing and the effect of irradiation to reduce the microbial contamination of the products were investigated. Among 9 food items tested, there were no viable cells in the ham, seasoned and cooked beef, imitation crab leg, fried egg, and seasoned burdoc. Cucumber, surimi gel, and seasoned and blanched spinach were counted at 5.07$\pm$0.97, 3.50$\pm$0.14, and 5.41$\pm$0.51 log CFU/g, respectively. Irradiation at 1 kGy reduced the number of microorganism in these ready-to-eat foods to an undetectable level. However, the dried laver showed an 8.83$\pm$0.10 log CFU/g and an irradiation at 3 kGy reduced the level to only 7.14$\pm$0.23. Sensory evaluation of the irradiated Kimbab prepared from these food materials indicated that the measure of the control of the sensorial quality should be provided before applying an irradiation to the prepared Kimbab.