• Korean Journal of Remote Sensing
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• v.14 no.4
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• pp.353-365
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• 1998

Light absorption coefficient per unit mass of particles, i.e., specific absorption coefficient, is important as one of the main parameters in developing algorithms for ocean color remote sensing. Specific absorption coefficient of chlorophyll ($a^*_{ph}$) and suspended sediment ($a^*_{ss}$) were analyzed with a spectrophotometer using the "wet filter technique" and "Kishino method" for the seawater collected in the Yellow and Mediterranean Sea. An improved data-recovery method for the filter technique was also developed using spectrum slopes. This method recovered the baselines of spectrum that were often altered in the original methods. High $a^*_{ph}({lambda})$ values in the oligotrophic Mediterranean Sea and low values in the Yellow Sea were observed, ranging 0.01 to 0.12 $m^2$/mg at the chlorophyll maximum absorption wavelength of 440 nm. The empirical relationship between $a^*_{ph}$(440nm) and chlorophyll concentrations () was found to fit a power function ($a^*_{ph}$=0.039 $^{-0.369}$), which was similar to Bricaud et al. (1995). Absorption specific coefficients for suspended sediment ($a^*_{ss}$) did not show any relationship with concentrations of suspended sediment. However, an average value of $a^*_{ss}$ ranging 0.005 - 0.08 $m^2$/g at 440nm, was comparable to the specific absorption coefficient of soil (loess) measured by Ahn (1990). The morepronounced variability of $a^*_{ss}$ than $a^*_{ph}$ was determined from the variable mixing ratio values between particulate organic matter and mineral. It can also be explained by a wide size-distribution range for SS which were determined by their specific gravity, bottom state, depth and agitation of water mass by wind in the sea surface.

• Annals of Clinical Microbiology
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• v.22 no.1
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• pp.9-13
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• 2019

Background: The isolation of carbapenemase-producing Enterobacteriaceae (CPE) has become increasingly common. Continuous surveillance for these organisms is essential because their infections are closely related to outbreaks of illness and are associated with high mortality rates. The aim of this study was to develop and evaluate multiplex PCR as a means of detecting several important CPE genes simultaneously. Methods: We aimed to develop a multiplex PCR that could detect seven CPE genes simultaneously. The multiplex PCR was composed of seven primer sets for the detection of KPC, IMP, VIM, NDM-1, GES, OXA-23, and OXA-48. We designed different PCR product sizes of at least 100 bp. We evaluated the performance of this new test using 69 CPE-positive clinical isolates. Also, we confirmed the specificity to rule out false-positive reactions by using 71 carbapenem-susceptible clinical strains. Results: A total of 69 CPE clinical isolates showed positive results and were correctly identified as KPC (N=14), IMP (N=13), OXA-23 (N=12), OXA-48 (N=11), VIM (N=9), GES (N=5), and NDM (N=5) by the multiplex PCR. All 71 carbapenem-susceptible clinical isolates, including Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa, showed negative results. Conclusion: This multiplex PCR can detect seven CPE genes at a time and will be useful in clinical laboratories.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.233-240
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• 2005

To discover new functional materials using edible plants, antioxidant activities of methanol extracts from various parts of seven wild vegetables were investigated in vitro. Total polyphenol contents, determined by Folin-Denis method, varied from 16.74 to $130.22{\mu}g/mg$. Radical-scavenging activities of methanol extracts were examined using ${\alpha},\;{\alpha}-diphenyl-{\beta}-pirrylhydrazyl$ (DPPH) radicals and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) assay. Inhibition effects on peroxidation of linoleic acid determined by ferric thiocyanate (FTC) method and on oxidative degradation of 2-deoxy-D-ribose in Fenton-type reaction system were dose-dependent. Athyrium acutipinulum Kodama (leaf and rood), Achyranthes japonica (Miq.) Nakai (seed), and Solidago virga-aurea var. gigantea Nakai (root) showed relatively high antioxidant activities in various systems.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.2
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• pp.153-165
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• 2014

Carbon dioxide capture and storage (CCS) technology is recognizing one of method responding the climate change with reduction of carbon dioxide in atmosphere. In Korea, due to its geological characteristics, sub-seabed geological $CO_2$ storage is regarded as more practical approach than on-land storage under the goal of its deployment. However, concerns on potential $CO_2$ leakage and relevant acidification issue in the marine environment can be an important subject in recently increasing sub-seabed geological $CO_2$ storage sites. In the present study effect data from literatures were collected in order to conduct an effect assessment of elevated $CO_2$ levels in marine environments using a species sensitivity distribution (SSD) various marine organisms such as microbe, crustacean, echinoderm, mollusc and fish. Results from literatures using domestic species were compared to those from foreign literatures to evaluate the reliability of the effect levels of each biological group and end-point. Ecological effect guidelines through estimating level of pH variation (${\delta}pH$) to adversely affect 5 and 50% of tested organisms, HC5 and HC50, were determined using SSD of marine organisms exposed to the $CO_2$-induced acidification. Estimated HC5 as ${\delta}pH$ of 0.137 can be used as only interim quality guideline possibly with adequate assessment factor. In the future, the current interim guideline as HC5 of ${\delta}pH$ in this study will look forward to compensate with supplement of ecotoxicological data reflecting various trophic levels and indigenous species.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.160-169
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• 2009

Poly-$\gamma$-glutamic acid ($\gamma$-PGA) was mixed natural flora of Bacillus subtilis, contaminated from cooked soybeans. Also, it was performed to find out the antiallergic activity by using NC/Nga mice, in vitro. The $\gamma$-PGA (PGA-HM : PGA-high molecular weight), Molecular weight 300 kDa, was decomposed and made PGA-LM (PGA-low molecular weight) which has molecular weight below 30 kDa by sonication. Therefore, it was same result between PGA-HM and PGA-LM, and reported PGA-LM as basic result. We found that PGA-LM contains antiallergic efficacy that inhibit B cells and Th2 cells activation from isolated CD4+T cells in NC/Nga atopic dermatitis model mice, and not show a cytotoxicity in the hFCs. To investigate the effects of these PGA-LM in vitro, isolation of splenic B cell and CD4+ T cells in atopic dermatitis mice were used. To elucidate the role of PGA-LM in anti-CD40+ interleukin-4 (IL-4)-mediated B-cell activation, showed that the capacity of B cells to expression IL-$1\beta$, IL-6, and TNF-$\alpha$ mRNA down-regulated, and IL-10 mRNA up-regulation by PGA-LM treatment, but it had no effect on TGF-$\beta$ expression. In addition to CD4+IFN-$\gamma$+ and CD4+CD25+foxp3+, the functions of PGA-LM in the development of the CD4+CD25+foxp3+ and CD4+IFN-$\gamma$+cells, the phenotype and functions of PGA-LM induced CD4+CD25+foxp3+, and CD4+IFN-$\gamma$+cells in CD4+T cells. These results suggested that PGA-LM could change cytokine production and generate CD4+CD25+foxp3+ Tregs in NC/Nga mice, and may be effective for immunotherapy in patients with AD.

• The Korean Journal of Mycology
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• v.27 no.1 s.88
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• pp.10-14
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• 1999

A single phase composter was constructed by modifying the conventional mixer of sawdust for the cultivation of oyster mushroom Pleurotus ostreatus. The machine was designed on the basis of 3-phase-1 system which was controlled in prewetting, pasteurization and fermentation processes. In composting 200 kg of straw and cotton waste in the machine, it took 20 minutes in prewetting step and also to hours at $65^{\circ}C$ in pasteurization process. Postfermentation by aerothermophiles was completed by treating the compost at $45^{\circ}C-50^{\circ}C$ for 48 hours which was shorten 24 hours from the conventional method. In the postfermentation at high temperature, forced aeration and/or vigorous mixing process(es) played a great role in the improvement of spawn quality. The growth of mycelium of oyster mushroom was excellent in the culture combinated with 3 parts of surface inoculation and 7 parts of mechanical mixing.

• Food Science and Preservation
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• v.23 no.2
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• pp.145-154
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• 2016

This study investigated the possibility of usage of freeze-dried ingredients for the preparation of Nabak kimchi. The quality characteristics of Nabak kimchi using freeze-dried ingredients (radish, kimchi cabbage, green onion, garlic and ginger) were monitored during storage at $4^{\circ}C$. The initial pH of Nabak kimchi was 5.76~5.93, however, it decreased significantly over increasing storage periods (p<0.05). The titratable acidity of Nabak kimchi increased during storage, reaching 0.43~1.08%. Among the freeze-dried samples, those treated with freeze-dried radish and minor ingredients showed lower titratable acidity than that of the control. The initial number of total aerobic and lactic acid bacteria were 5.57~6.25, and 5.52~6.24 log CFU/g, respectively. After 28 days, the population of total aerobic and lactic acid bacteria in the raw ingredients and freeze-dried minor ingredients was less than 8.0 log CFU/g, but more than 9.0 log CFU/g in other samples. Yeasts and molds in Nabak kimchi were detected up to 2~3 log CFU/g, but coliforms were not detected in all samples during storage. The score of firmness and overall acceptability in the control, raw ingredients and freeze-dried minor ingredients were significantly higher than others (p<0.05). These results indicated that freeze-dried ingredients, such as green onion, garlic, and ginger, can be used in kimchi and would delay microbial growth and extend the shelf-life of kimchi without any deduction of sensory quality.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.169-182
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• 2014

This study investigates the physicochemical quality characteristics of tomato sauce added with different kinds of pimpinella brachycarpa. The results are as follows. The pH of tomato sauce added with freeze-dried pimpinella brachycarpa, in contrast to the tomato sauce with raw pimpinella brachycarpa, decreased as the addition quantity of the sample increased. As for sugar content, PBP0 with Pimpinella brachycarpa contained was shown to be the highest with 10.83. For chromaticity, all values (e.g, L, A and B) of tomato sauce added with pimpinella brachycarpa and with freeze-dried pimpinella brachycarpa decreased showing significant differences among the samples as the addition quantity of the samples increased. With increased addition quantity of the sample with freeze-dried Pimpinella brachycarpa, its water content decreased. PBP4, addition group with 4% of freeze-dried Pimpinella brachycarpa, was shown to be the highest DPPH free radical scavenging activity as 29.58. When adding Pimpinella brachycarpa to tomato sauce, a total number of micro-organisms decreased. In case of adding raw Pimpinella brachycarpa rather than freeze-dried Pimpinella brachycarpa, it created a further effect on an inhibitive action of growing and developing micro-organisms. In the preference of tomato sauce with Pimpinella brachycarpa, PBF2 with 2% of Pimpinella brachycarpa had the highest score as 5.1 for the color. For taste, 3.7, the lowest taste score, was shown in PBF1with 1% of Pimpinella brachycarpa. The overall preference revealed that PBF2 was the highest scoring 5.8.. PBF3 was scored highest with 5.9 for overall preference. From the comprehensive findings, 2~3% of the addition ratio between raw Pimpinella brachycarpa and freeze-dried Pimpinella brachycarpa in the production of tomato sauce is considered the most preferable.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.327-334
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• 2013

For the development of hardy kiwi wine, we arranged for the post-maturity of hardy kiwi fruit, treated them with calcium carbonate and a pectinase enzyme complex, investigated the resulting physicochemical properties and conducted a sensory evaluation. The period determined for creating post-maturity in the hardy kiwi fruit was determined as 5 days storage at room temperature following maturity. During this time the yield of fruit juice was increased from 22.1% to 53.5% using 0.1% (v/v) cytolase PCL5 for 2 h at room temperature. 0.1% (w/v) calcium carbonate was also added during the process of aging, for the reduction of the sour taste. The fermentation trial of the hardy kiwi wine was prepared using water (25% or 50%), sugar ($24^{\circ}brix$), 0.1% (w/v) $CaCO_3$, 0.1% (v/v) cytolase PCL5, $K_2S_2O_5$ (200 ppm), and yeast ($1.5{\times}10^7$ cell/ml). Fermentation then occurred for 2 weeks at $20^{\circ}C$. The pH value, total acidity, alcohol, and reducing sugar content of the resulting hardy kiwi wines of 25% (v/w) and 50% (v/w) water, were in a range of pH 3.4-3.7, 1.12-1.21%, 14.3-14.4%, and 15-16 g/l, respectively. Citric acid and fructose constituted the major organic acids and the free sugar of the 25% and 50% hardy kiwi wine, respectively. Volatile flavor components, including 10 kinds of esters, 8 kinds of alcohols, 5 kinds of acids, 3 kinds of others and aldehydes, were determined by GC analysis. The results of sensory evaluation demonstrated that 50% hardy kiwi wine is more palatable than 25% hardy kiwi wine.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.1-9
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• 2012

This study's aim was to isolate microorganisms producing agarase with a high activity, with possible applications in improving the performance of the pretreatment processes for bioethanol production. Marine algaes were collected from the south coast of Korea, from which three kinds of microorganisms were isolated. After a 4-day culture of these strains at $25^{\circ}C$, crude enzymes were obtained from culture supernatant or cell-free extract by ammonium sulfate precipitation and membrane dialysis. Agarase activity was observed in these crude enzymes. Notably higher specific activity was observed in the crude enzyme obtained from the culture supernatant rather than that from the cell-free extract. This indicates that a secreted enzyme has a much greater activity than a cellular enzyme. Crude enzymes from the GNUM08122 strain were inferred to have ${\alpha}$-agarase activity because release of p-nitrophenol was observed, possibly due to the cleavage of p-nitrophenyl-${\alpha}$-D-galactopyranoside. The 16S rRNA sequence of GNUM08122 showed a close relationship to Pseudoalteromonas issachenkonii KMM 3549 (99.8%) and Pseudoalteromonas tetraodonis IMA 14160 (99.7%), which led us to assign it to the genus Pseudoalteromonas. Biochemical and physiological study revealed that this strain can grow well at $40^{\circ}C$ under a wide range of pH (pH 4~8) in high-salt conditions (10% NaCl).