• Korean Journal of Microbiology
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• v.47 no.4
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• pp.364-374
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• 2011

Lactobacillus brevis DK25 isolated from Dongchimi was identified by physiological and biochemical tests and 16S rDNA sequence analysis. Bacteriocin of L. brevis DK25 exhibits inhibitory activity against Enterococcus faecalis and Listeria monocytogenes when using agar well diffusion method. Maximal production of bacteriocin was reached in the beginning of the stationary phase, and inhibitory activity declined after the late stationary phase. This result suggested that bacteriocin was produced in a growth-associated manner. Complete inactivation of bacteriocin activity was observed after treatment with protease, but the activity was stable between pH 4-9 and heat resistant (30 min at $100^{\circ}C$). Bacteriocin showed a concentration-dependent antimicrobial activity against L. monocytogenes KCTC 3569. Moreover, the application experiment showed that combination of bacteriocin (320 AU/ml) with potassium benzoate (0.05%) could significantly reduce the counts of L. monocytogenes KCTC 3569 in mayonnaise during storage at 4 or $25^{\circ}C$ for 10 days. Thus, bacteriocin from L. brevis DK25 may be used for hurdle technology by combination with potassium benzoate in order to increase pathogenic bacteria inactivation in food processing and food safety control.

• Journal of Life Science
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• v.18 no.4
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• pp.537-541
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• 2008

White adipose tissue is now recognized as an important endocrine organ which secretes various signal factors and proteins termed 'adipokine'. Haptoglobin (Hp), which has been known as an acute phase protein, belongs to the adipokine. However, the function of Hp in adipose tissue remains unclear. To verify the role of Hp in preadipocytes, in this study, 3T3-L1 preadipocyte cells were stably transfected with human Hp gene and Hp-overexpressing cells were made. The Hp had no effect on cell growth of preadipocytes. By RT-PCR and Western blot analysis, the Hp inhibited gene expression of IL-6 and COX-2 and enhanced HO-1 synthesis in preadipocytes. Moreover, invasion assay showed the Hp suppressed migration of monocytes to preadipocytes. These findings suggest that the Hp may inhibit an inflammatory reaction in adipose tissue by regulating the expressions of pro-inflammatory and anti-inflammatory mediators, and by repressing monocytes/macrophages infiltration.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.519-521
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• 2010

An Asiatic lily cultivar 'Asian Flame' was bred in 2007 at National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA) of Korea. The crossing was conducted between female parent A94-34 ('Montreux' ${\times}$ 'Anabelle') and male parent 'Fire' by stigmatic pollination at Suwon in 1996. First selection was done and tentatively named as A98-98 in 1998. After in vitro multiplication and bulb production of A98-98 line, growth and flowering characteristic tests has been conducted from 2005 to 2007. The evaluation of characteristics and preference were surveyed at a lily flower show of NIHHS in 2007 in Taean. The new cultivar 'Asian Flame' flowers in middle of June and grows to an average of 122.7 cm in height. Flowers bloom upward-facing, red (RHS 45B) petals. Year-round flowering is possible by storage of the bulb under $-1.5^{\circ}C$ conditions. For forcing culture, it is necessary to add calcium to the fertilizer or remove side scales of large bulb to prevent leaf scorch.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.153-163
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• 2020

Compared to gaeous hydrogen, liquid hydrogen has approximately 1/800 volume, 800 times higher volumetric energy density at the same pressure, and the advantage of lower explosion risk and easier transportation than gaseous hydrogen. However, hydrogen liquefaction requires larger scale facility investment than simple compression storage method. Therefore, the research on energy-saving hydrogen liquefaction processes is highly necessary. In this study, helium/neon (mole ratio 80 : 20) refrigeration cycle was investigated as the main refrigeration process for hydrogen liquefaction. Process simulation for less energy consumption were carried out using PRO/II with PROVISION V10.2 of AVEVA. For hydrogen liquefaction, energy consumption was compared in three cases: Using a helium/neon refrigerant cycle, a SMR+helium/neon refrigerant cycle, and a C3-MR+helium/neon refrigerant cycle. As a result, the total power consumptions of compressors required to liquefy 1 kg of hydrogen are 16.3, 7.03 and 6.64 kWh, respectively. Therefore, it can be deduced that energy usage is greatly reduced in the hydrogen liquefaction process when the pre-cooling is performed using the SMR process or the C3MR process, which have already been commercialized, rather than using only the helium/neon refrigeration cycle for the hydrogen liquefaction process.

• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.238-243
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• 2006

The populations of V. parahaemolyticus were enumerated in oysters collected in wholesale seafood markets in Seoul and tested in various possible condition. The populations of oysters soled in the markets were ranged $<2\sim1.4\times10^6$ MPN/100 g from April to November in 2005. In the case of oysters added with V. parahaemolyticus of $4\times10^3$ CFU/100 g, the highest population numbers were $1.4\times10^7$ CFU/100 g, $5.4\times10^5$ CFU/100 g and $2.7\times10^4$ CFU/100 g at $36^{\circ}C$ after culturing for 15 hours, at $25^{\circ}C$ after 15 hours and at $4^{\circ}C$ after 15 hours, respectively. But the difference of the populations of V. parahaemolticus in oysters stored in the icebox with ice for bulked sale and displayed in stalls on ice for the small packaged sale was not significant. In the case of oysters carried with ambient temperature at $30.8^{\circ}C$, the V. parahaemolyticus density was dramatically increased from $2.7\times10^5$ to $1.4\times10^8$ MPN/100 g. It was indicated it is important to carry the oysters to home with ice after purchase. Even after the washing two times with 21 tap water, the common cooking method in Korea was not greately make the decrease of V. parahaemolyticus density from $1.4\times10^8$ MPN/100 g to $9.0\times10^5$ MPN/100 g. So it is noticed to stored in low temperature after cooking, especially in hot seasons.

• Journal of Food Hygiene and Safety
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• v.33 no.2
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• pp.94-101
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• 2018

Although Kimchi has health benefits, food poisoning associated with consumption of Kimchi has been frequently reported. Accordingly, microbiological properties of Kimchi (100 samples) and washing effects on microbial reduction against its ingredients (200 samples) were examined. Total aerobic bacteria, coliforms, Escherichia coli, Bacillus cereus, and Clostridium perfringens were quantified. In addition, B. cereus, Salmonella spp., Enterohemorrhagic E. coli, C. perfringens, Campylobacter jejuni/coli, Staphylococcus aureus, Vibrio parahaemolyticus, Listeria monocytogenes, and Yersinia enterocolitica were analysed qualitatively. Total aerobic bacteria count was approximately 1.4-9.0 log CFU/g, which were highest in ginger (8.8 log CFU/g), and Chonggak Kimchi (9.0 log CFU/g). The range of coliform counts detected in all raw materials was 0.5-7.3 log CFU/g and ginger showed the greatest number 7.3 log CFU/g among others. Contamination was decreased to 0.2-3.2, 0.3-2.7, and 1.0-3.9 log CFU/g for total aerobic bacteria, coliforms, and B. cereus, respectively, after washing. Minimising microbial contamination in Kimchi ingredients is necessary to ensure the safety of Kimchi. These results indicate that washing is a useful method to reduce bacterial contamination in Kimchi.

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.39-50
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• 1988

Main lactic acid bacteria fermenting “Baechu Kimchi” and” “Dongchim”, which are indigenous fermented food in Korea, were isolated at optimum fermentation period and identified. The three groups of food preservatives-sorbic acid, p-hydroxybutyl benzoate (POBB), p-hydroxypropyl benzoate (POPB), and sorbic acid-POBB were prepared, and the effect of the food preservatives and various salt concentrations on those lactic acid bacteria was examined. The results obatined are as follows; 1. Lactic acid bacteria were isolated from “Baechu Kimchi” and “Dongchimi”and identifed as Leuconostoc mesonteriodse, Lactobacillus plantatum, Lactobacillus brevis, Streptococcus faecalis, and Pedicoccus pentosaceus. 2. Lactic acid bacteria were grown much better at 0.5-2% NaCl level than 0% NaCl level. 3. Among the isolated lactic acid bactera, Lactobacillus plantarum showed the highest acid producibility. The lower the concentration of NaCl, the higher the acid producibility by Leuconostoc mesentroides, and the other bacteria produced a large amount of acid at 0.5-2.5% NaCl level. 4. Both the sorbic acid (0.05-0.1%) and sorbic (0.05%)-POBB (0.004%) groups showed the highest preservatives effect. In contrast, however, POPB (0.01% ) Group showed the lowest effect, and the preservatives effect was enhanced by the addition of NaCl. Lactobacillus plantarum was least affected by all preservatives, whereas Leuconostoc mesentroides was most affected by them.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.349-355
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• 2000

This study was conducted to enhance the storage stability of fermented shrimp with different salt contents using a high hydrostatic pressure. The effects of the magnitude of pressure and treatment time on the microorganisms of the fermented shrimp were investigated. The highest microbial counts with respect to the salt levels were observed at 18% salt, showing $3.4{\times}10^5\;CFU/g$ for general bacteria, $6.4{\times}10^4\;CFU/g$ for halophilic bacteria, $4.2{\times}10^5\;CFU/g$ for yeast and $3.0{\times}10^4\;CFU/g$ for halophilic yeast. The degree of sterilization increased with the magnitude of pressure and treatment time, and the sterilization could be analyzed by the first order reaction kinetics. The sterilization rate constants $(k_p)$ of the halophilic bacteria was lower than that of general bacteria. The $log(k_p)$ increased linearly with pressure and the slope of the regression line of the halophilic bacteria was greater than that of general bacteria, indicating that the sterilization of the halophilic bacteria was more dependent on the pressure. High hydrostatic pressure treatment was an effective non-thermal sterilization method for the salted and fermented shrimp, and the optimum treatment condition was for 10 min at 6,500 atm.

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.350-355
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• 1978

An attempt was made to compare the antioxidant activity of ethanol extracts of a glucose-ammonia (0.2 M+0.2 M) browning mixture with that of the corresponding glucose-glycine mixture, in soybean oil substrates, on the basis of peroxide value (POV), thiobarbituric acid value (TBA-value) and acid value (AV) development. Absorbances, at 470 nm, of the former mixture after 2 and 5 hour browning were 1.88 and 3.42 while those of the latter mixture were 0.02 and 0.07. The POVs of the supstrates containing the extracts taken after 2, 15, and 40 hrs from the former mixture were 15.8, 14.2, and 12.6 after 30 day storage at $42.3{\pm}2.6^{\circ}C$. Those of the latter mixture were 17.4, 16.1, and that of the control was 82.1. TBA and acid value developnent followed similar trends. These results indicated that the antioxidant activity of the extracts of the glucose-ammonia mixture was slightly stronger than that of the glucose-glycine mixture. They also suggested that effective antioxidants had already been formed in the earlier stages of the glucose-anmonia mixture, and that brown-pigments formed did not contribute significantly to the activity of the mixture.

• FLOWER RESEARCH JOURNAL
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• v.18 no.3
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• pp.216-219
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• 2010

An Asiatic lily cultivar 'Yeri' was developed in 2005 at National Institute of Horticultural and Herbal Science (NIHHS), Rural Development Administration (RDA), Korea. The cross was made in 1993 between Asiatic lily 'Geneve', a light pink colored cultivar, and 'Montreux', deep purple colored cultivar. The first selection was done and was tentatively named as 'A95-68' in 1995. After in vitro multiplication and bulbing production, growth and flowering characteristic tests were conducted from 1996 to 2003. The evaluation of characteristics was performed and named as 'Wongyo C1-19' in 2005 that was registered as 'Yeri' to the registration office of Korea Seed & Variety Service. 'Yeri' flowered at the first of July and grew average 34.6 cm stem in length. Flowers bloomed facing upward, unspotted in petals and deep purple (RHS, RP58A). The size of flower was 13.3 cm. Mean petal length and width was 7.7 cm and 2.7 cm, respectively. Leaves were 5.1 cm long and 0.5 cm wide, respectively. The weight and size of bulb were 9.6 g and 11.7 cm, respectively. Year-round flowering can be done by storing the bulb under $-1.5^{\circ}C$ conditions. For forced cultivation, it was necessary to add calcium to the fertilizer or remove side scales to prevent leaf scorch. It was needed to control Botrytis disease in wet season.