• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.161-166
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• 2013

This study was carried out to investigate the physicochemical and microbiological characteristics of beef loin following microwave treatment at $4^{\circ}C$. Two types of microwave treatment were applied. i.e., continued microwave treatment (CW) and holding microwave treatment (HW). The L value increased, while a and b values were not significantly different among the samples as the storage time and microwave dose increased. The initial pH and after 3 days ranged from 5.51-5.74 and 6.32-6.51, respectively (p<0.05). The thiobarbituric acid value of all beef loins increased with increasing storage period and decreased with increasing microwave dose. The volatile basic nitrogen (VBN) content of the control was higher than that of the other samples and the VBN content decreased with increasing microwave dose. The total plate count of beef loins decreased with increasing microwave dose. This result indicated that T2 (100 W, HW) is most effective treatment with regard to the safety of beef loins without decreasing the physicochemical and microbiological characteristics.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.103-108
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• 2020

Shiga toxin-producing Escherichia coli (STEC) is an important pathogenic bacteria and can cause severe foodborne disease. For STEC detection, conventional culture methods have disadvantages in the fact that conventional culture takes a long time to detect and PCR can also detect dead bacteria. To overcome these problems, we suggest a bacteriophage amplification assay, which utilizes the ability of bacteriophages to infect living cells and their high specificity. We used a combination of six bacteriophages infecting E. coli to make the bacteriophage cocktail and added ferrous ammonium sulfate as a virucidal agent to remove free-bacteriophages. When cherry tomato and paprika were artificially inoculated with the cocktail at a final concentration of around 3 log CFU/mL and were enriched for at least 5 h in mTSB broth with Novobiocin, approximately 2-3 log PFU/mL were detected through the bacteriophage amplification assay. Therefore, bacteriophage amplification assay might be convenient and a useful method to detect STEC in a short period of time.

• Korean Journal of Ecology and Environment
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• v.35 no.1 s.97
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• pp.45-51
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• 2002

This study was investigated to tile influences of clearcutting of timber harvesting on stream water quality at a natural deciduous forest catchment within the Seoul National University Research Forests in Mt. Baegun, Chunnam province during the periods of 1993 to 2001. Soil chemical ingredients and stream water qualities were monitored at 13 ha clearcutting site, non-treatment site and included in these catchment nearby. After the harvesting first and End years, the levels of total- N,　and exchangeable ions ($K^+,\;Na^+,\;Ca^{2+},\;Mg^{2+}$) were decreased the values of before　harvesting, and after the harvesting 111th years and eighth years, respectively. But the chemical characteristics of soil were not changed at all. pH of water in the harvesting area was 6.5 in stream water. Among the nutrient, Cd, Pb, Cu, and phosphate were not found, and the level of BOD reached at the level of the domestic use for drinking. Turbidity, odor, taste, $NH_4\;^+-N,\;NO_3\;^--N$, standard plate count, and coliform were also low enough to be used as the domestic use for drinking in the near villagers. Total amount of cation, total amount of anion and total amount of ion in clearcutting site, non- treatment site and included in these catchment nearby were higher than clearcutting site and non- treatment site. But, there was no great difference.

• Research in Plant Disease
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• v.12 no.3
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• pp.153-157
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• 2006

In 2005, average temperature was lower, and average rainfall was less than those of previous year. The diseases of rice, barley, pepper, chinese melon, apple and oriental pear were surveyed. Bacterial blight, bacterial grain rot, and panicle disease of rice, black rot of pear, and white rot and bitter rot of apple were severe. Especially, brown rot of rice occurred four times higher than those of previous year. Panicle blight of rice increased about 3 times, compared with the previous year, presumed that the higher rainy days, rainfall and RH promoted spread of the fungal pathogens to panicles of rice. The diseases of rice leaf blast, sudden wilt syndrome, downy mildew and powdery mildew of chinese melon in plastic greenhouse, and virus diseases of hot pepper occurred distinctly less than those of the previous year. Another diseases surveyed occurred similar or less.

• Research in Plant Disease
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• v.16 no.1
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• pp.41-47
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• 2010

A total of 10,753 oligotrophic bacteria were isolated from the cultivated soils of red-pepper infected by Phytophthora blight disease in various regions of Korea (Chungju, Anmyon, Taean, Andong, Eumsung and Goesan). Seven bacteria isolates among these collected resources were selected by the first screening of in vitro antagonistic assay against major several plant pathogenic fungi including Phytophthora capsici. Finally, strain 7F was selected by pot assay for a possible biological control agent against Phytophthora blight disease of pepper seedling in the greenhouse. Strain 7F was identified as Bacillus subtilis on the basis of its 16S rDNA sequence analysis and as standardized biochemical characteristics assay kits such as API20 NE. In the experiment of P. capsici zoospore infected red-pepper on the pot test, infection rate of red-pepper with nonetreatment to Phytophthora blight disease was 87%, while the rate was only 6% in the pot treated with strain 7F. This result indicated that the Bacillus subtilis strain 7F will be useful as a potential biocontrol agent for Phytophthora blight disease of red-pepper.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.65-69
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• 2013

In situ measurement of a primary production in East Sea, a marginal sea with a fair accessibility, is nonetheless an arduous task because of dynamic variability. In this study, we estimated the mean value of background (gross) primary production over the warm region of the East Sea based on a biogeochemical hypothesis. We propose an immiscible-shoaling hypothesis for the estimation of primary production, which assumes that primary production in the warm region occurred only by the nutrient supply through the Korea Strait. Annual primary production thus estimated is $209\;gC\;m^{-2}\;y^{-1}$, which is comparable to the satellite-based estimates of net primary production in the region. However, since this hypothesis assumes that primary production is based on only the new nutrients supplied to the system, primary production would increase by 40% if we release the assumption, and assume f = 0.6. This suggests that nutrient influx through the Korea Strait alone is more than enough to support primary production previously reported. Primary production may increase as much as two times if we considered other external perturbations excluded intentionally to estimate the background level of primary production, such as coastal upwelling, submerged ground water discharge, aeolian input, ocean dumping, and mixing by typhoons as well as the contribution of cyanobacteria that has not been quantified in the region. This implies the primary production in the warm region of the East Sea would be comparable to that of the Peru upwelling region with f = 0.6.

• Pediatric Infection and Vaccine
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• v.23 no.3
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• pp.188-193
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• 2016

Purpose: This study identified the characteristics differentiating node-first presentation of Kawasaki disease (NFKD) from bacterial cervical lymphadenitis (BCL) and typical Kawasaki disease (KD). Methods: From July 2007 to June 2015, the medical records of patients with BCL, NFKD, and typical KD were retrospectively reviewed. We analyzed and compared the demographic, clinical, laboratory, and imaging characteristics of the cohorts. Results: Twenty-two patients with BCL, 37 with NFKD, and 132 with typical KD were included in this study. Patients with BCL had longer durations of hospitalization than patients with NFKD. Bilateral and multiple enlarged cervical lymph nodes were associated more with NFKD than BCL. Compared with BCL patients, NFKD patients had lower platelet counts, higher percentages of neutrophils, and higher C-reactive protein (CRP) levels. NFKD patients were older and presented with higher white blood cell counts, percentages of neutrophils, absolute neutrophil counts, and CRP levels as well as lower platelet counts and alanine aminotransferase levels than typical KD patients. Conclusions: In febrile patients with cervical lymphadenopathy, the combination of bilateral and multiple enlarged nodes, low platelet count, high percentage of neutrophils, and high CRP levels should prompt consideration of NFKD for prevention of delayed diagnosis of KD.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.2
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• pp.146-155
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• 1989

A series of the experiments were conducted to evaluate the effects of the water-logging in continuous cropping soils of cucumber. Some of the results obtained from these experiments are summarized as follow: The values of pH in water-logged treatments were from 5.50 to 5.90. Those of EC were less than 0.3 mmhos/cm, were lower than those of control plot. The ratios of Ca/Mg, Ca/K, Mg/K respectively 2.5, 4.8, 2.0, were similar to the standard values. These changes were suitable for cucumber planting. And the number of bacteria among the microflora were determined increased from $10^6$ to $10^7\;cells/g$ dry soil, while that of the Fungi, Fusarium spp, Pythium spp, and Phythophthora spp decreased. In proportion to these changes of microflora, the ratios of B/F in water-logging plot were higher than in the control plot. The contents of Biomass-C were showed 10.47mg/100g soil to 36.12 mg/100g soil, and the contents of that in water-logging were more than in control plots.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.177-182
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• 2020

Copper possesses antimicrobial properties against certain bacteria and fungi. In this study, changes in microbial population, color and the antioxidant properties of dried red pepper powder (RPP) by contact with the surface of a copper plate were investigated. Lightness of RPP increased after treatment on the copper plate for 2 h at 55℃. The numbers of total aerobic mesophilic bacteria in RPP increased by 0.61 and 0.50 log on the surface of stainless steel and copper plates during 24 h at 37℃, respectively. The population of yeast and mold was reduced by 90% in the RPP treated on both copper and stainless steel plates under the same condition. Yeast and mold were significantly reduced on the copper plate during 2 h at 55℃. Scavenging activities of RPP treated on the copper plate for 24 h at 37℃ against DPPH radical were decreased; those for 2 h at 55℃ against ABTS radical were rather enhanced. The results suggest that copper might be applied in the processing and storage equipment in relation to RPP products for antimicrobial purposes.

• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.240-248
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• 2014

In this study, we analyzed 24 pieces ($4{\times}3{\times}2$) of pork jerky produced using raw meat and we then randomly assigned the hind leg meat to a treatment group. In addition, the effects of storage according to aerobic plate counts and sensory evaluation on pork jerky were examined. Form the results, We found that volatile basic nitrogen (VBN) content and aerobic plate counts of pork jerky gradually increased with increased storage time, ; moreover, there was a significant difference between the treatment groups and the control group (p<0.01). However, the counts did not increase as significantly in the ginseng powder group (B), as compared to the ginger powder group (A) (p<0.05). The sensory evaluation of pork jerky peaked during the second week of storage in all treatment groups, after which these characteristics gradually decreased (p<0.05). In addition, these characteristics were generally higher in the control group, compared to the treatment groups. When comparing the ginseng powder addition group (B) and ginger powder-addition group (A), only color was significantly higher in the ginger powder group. Based on this study as well as previous studies, storage of pork jerky significantly affects the sensory evaluation of raw pork. Ginger powder may have a more beneficial effect than other treatments on the sensory evaluation. Additionally, in all treatment groups, sensory characteristics were significantly higher in the ginger treated groups than in those of the ginseng-treated groups.