• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.732-741
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• 2009

This study was carried out to identify lactic acid bacteria isolated from commercial Kimchi. Twelve lactic acid bacteria strains were isolated from Chinese cabbage kimchi (Baechu kimchi) that was fermented for 4 days at room temperature after making kimchi, 6 strains from pickled ponytail radishes (Chongkak kimchi) that was fermented for 2 days, and 15 strains in radish cube kimchi (Kaktugi) that was fermented for 5 days, and 23 strains were isolated in pickled Wakegi (Pa kimchi) that was fermented for 4 days. Eight strains among the lactic acid bacteria of 12 strains isolated from Baechu kimchi (pH 4.0) were identified as Lactobacillus plantarum, 1 strain as Leuconostoc lactis, 2 strains as Lactobacillus casei subsp. pseudoplantarum, and 1 strain as Lactobacillus sake. Three strains among the lactic acid bacteria of 6 strains isolated from Chongkak kimchi (pH 4.5) were identified as Leuconostoc paramesenteroides, 2 strains as Leuconostoc mesenteroides subsp. mesenteroides, and 1 strain as Lactobacillus plantarum. Two strains among the 15 strains isolated in Kaktugi (pH 4.0) were identified as Leuconostoc lactis, 3 strains as Leuconostoc mesenteroides subsp dextranicum, 4 strains as Lactobacillus casei subsp. pseudoplantarum, and 4 strains as Lactobacillus coryniformis subsp. torquens. Twenty-two strains among the 23 strains isolated from Pa kimchi (pH 4.1) identified as L. plantarum and 1 strain was as Lactobacillus sake. From the results above, the dominant species of Baechu kimchi was confirmed as L. plantarum, Chongkak kimchi as L. paramesenteroides, Kaktugi as L. casei subsp. pseudoplantarum and L. coryniformis subsp. torquens, and Pa kimchi as L. plantarum.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.437-444
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• 2016

Rapid and reliable identification of microorganisms is important to maintain food quality and to control safety. MALDI-TOF MS-based identification methods are relatively fast and simple compared to other conventional methods including gram staining and biochemical characterization. A colony on subcultured media can be directly prepared on the analysis plate without further complex treatments. In this study, we confirmed the applicability of MALDI-TOF MS-based identification of foodborne pathogens such as Salmonella Enteritidis/Typhimurium, Staphylococcus aureus, Vibrio parahaemolyticus, Clostridium perfringens, Listeria monocytogenes, Yersinia enterocolitica, Bacillus cereus, Campylobacter jejuni, Campylobacter coli, and Cronobacter sakazakii on the Korea Food Standard Codex. MALDI-TOF MS data of the pathogenic reference strains were incorporated into a commercial MicroID (ASTA Inc.) database. Other pathogenic reference strains and seven isolates from various food samples were correctly identified to the species level by using the MicroID database. In conclusion, MALDI-TOF MS is comparable with commercial biochemical identification.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.599-606
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• 2021

In this study, an experiment and a reaction characteristic study were conducted to enhance the reaction activity of V₂O₅/WO₃/TiO₂ at 300 ℃ or less by adding selenium to the support, in a selective catalytic reduction method using ammonia as a reducing agent to remove nitrogen oxides. Se-TiO₂ and TiO₂ were synthesized using the sol-gel method, and used as a support when preparing V₂O₅/WO₃/TiO₂ and V₂O₅/WO₃/Se-TiO₂ catalysts. The reaction activity of our catalyst was compared with that of a commercial catalyst. The denitration efficiency of the catalyst using TiO₂ prepared by the sol-gel method was lower than that of the catalyst prepared using commercial TiO₂, but was improved by the addition of selenium. Thus, the effect of selenium addition on the catalyst structure was analyzed using BET, XRD, Raman, H₂-TPR, and FT-IR measurements and the effect of the increase in specific surface area by selenium addition and the formation of monomer and complex vanadium species on reaction characteristics were confirmed.

• Journal of fish pathology
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• v.34 no.2
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• pp.185-199
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• 2021

Vibriosis is an important septicemic bacterial disease that affects a variety of commercial fish species, including cultured Dicentrarchus labrax. Nanotechnology has become an important modern tool for fish diseases prevention. Furthermore, nanomaterials have the ability to prevent and treat fish diseases. The current study was aimed to identify the causative agent of massive mortality of D. labrax commercial farm in Alexandria, Egypt. Experimental infection and the median lethal dose (LD50) of pathogenic isolate were assessed. Also, the effect of ginger nanoparticles (GNPs) and Sacchromyces cerevisiae as feed additives for prevention of vibriosis in D. labrax was carried out. Similarly, the tissue immunstimulant genes, IL-1β and TLR2 were measured in the spleen of feeding groups. The clinical signs of naturally diseased D. labrax showed corneal opacity and paleness of gills with excessive mucous secretion. The post-mortem abnormalities were severe hemorrhage and adhesion of internal organs. After bacteriological isolation and identification, the causative agent of mortality in the current study was Vibrio alginolyticus. The LD₅₀ of V. alginolyticus was 1.5×10^5.4 CFU/ml. The experimentally infected D. labrax showed ulceration, exophthalmia and skin hemorrhages. The post-mortem findings of the experimentally infected D. labrax revealed internal hemorrhage, spleen darkness and paleness of liver. There is no mortality and 100% RPS in groups fed GNPs then injected with V. alginolyticus, in those fed a combination of GNPs and S. cerevisiae and a group fed normal diet then injected with physiological saline (control negative), respectively. Contrarily, there was 10% mortality and 87.5 RPS in the group fed S. cerevisae then injected with V. alginolyticus. On the other hand, the control positive group showed 79% mortality. The spleen IL-1β and TLR2 immunostimulant genes were significantly increased in groups of fish fed GNNP, S. cerevisiae and a combination of GNPs and S. cerevisiae, respectively compared to control group. The highest stimulation of those immunostimulant genes was found in the group fed a combination of GNPs and S. cerevisiae, while fish fed S. cerevisiae had the lowest level. Dietary combination of GNPs and S. cerevisiae was shown to be efficient in preventing of vibriosis, with greatest stimulation of spleen IL-1β and TLR2 immunostimulant genes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.1
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• pp.1-12
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• 2019

We investigated the nutritional components of the major commercial frozen seafood products (MCFSP) [sliced frozen-skipjack tuna (ST), -bigeye tuna (BET), -bluefin tuna (BFT), -yellowfin tuna (YT), fish steaks (FST), fish pancakes (FP), fish cutlets (FC), seafood cake balls (SCB), fried shrimp (FS), shrimp patties (SP), shrimp cutlets (SC)] in Korea. All species of sliced frozen tuna and FST were classified as low-calorie foods; the other frozen seafood products were classified as medium-calorie foods. The MCFSP were significant sources of nutritional and functional minerals: the SCB and SC provided calcium; the FST, FC, and SCB provided phosphorus; the BET, YT, and FST provided potassium; the FST, FC, and BFT provided magnesium; the FST, FP and SC provided iron; the SCB, FS, SP, and SC provided zinc; the YT and SCB provided copper; and the FC provided manganese. The total amino acid contents of the MCFSP were in the range of 6.85-26.34 g/100 g. Glutamic acid was the major amino acid in the SCB, FS, SP, and SC. Fatty acid contents were in the range of 386-2,925 mg/100 g; the major fatty acids in the ST, BFT and YT were 16:0, 18:1n-9, 22:6n-3. The MCFSP were not a significant source of vitamin A or riboflavin.

• Applied Chemistry for Engineering
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• v.32 no.1
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• pp.35-41
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• 2021

VWTi, which is used as a commercial catalyst in NH3-SCR, exhibits excellent denitrification performance at 300 to 400 ℃, but there is a problem that efficiency decreases at low temperatures below 300 ℃. Research on catalysts containing promoter to increase low-temperature denitrification efficiency is steadily progressing. However, research on the cause of the improvement in low-temperature denitrification efficiency of the catalyst and the catalyst properties is insufficient. In this study, it was confirmed that by adding Sb to VWTi, denitrification performance was improved by more than 10% in NH3-SCR reaction below 300 ℃. At this time, the space velocity and the size of the catalyst particles were controlled to exclude the influence of external/internal diffusion. In addition, the catalytic properties according to the presence or absence of Sb were investigated by performing BET, TEM/EDS, O2-TPD, H2-TPR and DRIFTs analysis. It was judged that the addition of Sb increased the adsorbed oxygen species on the surface of the catalyst, thereby enhancing the redox properties of the catalyst at low temperature and exhibiting excellent denitrification performance.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.263-274
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• 2022

Lentinula edodes is an important commercial mushroom and there have been several reports of viral infections in L. edodes. Two mycoviruses (LeV-HKB and LeNSRV1) were detected in Sanbaekhyang (NIFoS 2778) and Taehyanggo (NIFoS 4317), the sawdust-cultivated commercial strains. The vertical transmission rates of the viruses were investigated by detecting the viruses in 80 monokaryotic strains derived from basidiospores isolated from the fruiting bodies of each strain. Most of the monokaryotic strains were infected with the virus and the two viruses showed different levels of meiotic stability, with LeV-HKB showing higher meiotic stability than LeNSRV1. Therefore, it seems that the vertical transmission mechanism of mycoviruses is different depending on the virus species. We also examined the mycelial growth rate of the monokaryotic strains and compared the growth rate according to virus infection status. Although there was no statistically significant correlation between viral infection and mycelial growth rate, we found that the average growth rate was reduced by additional virus infection. We expect our data to contribute to a greater understanding of the mechanism of the vertical transmission of mycoviruses, and promoting breeding using virus-free monokaryotic strains.

• Journal of Life Science
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• v.22 no.7
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• pp.987-990
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• 2012

Mungbean sprout rot is one of the most serious problems of the commercial mungbean sprout industry. In this study, 70 strains of mungbean sprout rot pathogens were isolated from rotten sprouts at different time intervals. The pathogenicity of the isolated pathogens was tested. The highly pathogenic strain (YV-St-033) was identified as Pseudomonas sp. by 16S rRNA gene sequencing. In phylogenetic analysis, the YV-St-033 strain was grouped with P. mosselii, P. putita, P. fluorescens, P. entomophila, and P. lecoglossicida. The results of the 16S rRNA gene sequence analysis revealed that the YV-St-033 strain shared the highest sequence identity (more than 99%) with the P. mosselii R10 strain. The mungbean lines of Yeungnam University germplasm were screened against the YV-St-033 strain. Based on the growth rate of the sprouts after 3 days of inoculation with the pathogen, the YV148 line was highly resistant to the pathogen. The remaining lines were either partially or fully infected. The highly resistant line YV 148 is suitable for future breeding programs due to their thin sprouts and fast growing nature.

• Clean Technology
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• v.22 no.3
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• pp.190-195
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• 2016

The thermal decomposition of waste energetic materials such as TNT, RDX and composition B in a commercial rotary kiln has previously been carried out. As part of the demilitarization process, the thermal decomposition of homogeneous double base propellant (DB) used in M8 and consisting predominantly of nitrocellulose and nitroglycerine is examined with respect to a number of operating conditions. A single condensed phase reaction with 4 species and 365 gas phase reactions and 59 species are considered. Simulation results show the sensitivity of the thermal decomposition of DB with temperature and velocity. At relatively low velocity with constant inlet hot air temperature, temperature in the rotary kiln was found to be highest, 953 K and 1300 K for cases 3 and 6 respectively. Illustrating that optimum operating temperature can be achieved by controlling the inlet velocity without additional cooling systems.

• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.318-323
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• 2007

The feeding habits of Pacific cod (Gadus macrocephalus) were studied based on the examination of stomach contents of 192 specimens collected from November, 2005 to January, 2006 in the coastal waters off Gadeok-do, Korea. The size of Pacific cod ranged from 35 to 82 cm in standard length (SL). Pacific cod mainly consumed shrimps such as Eualus spathulirostris, Crogon hakodatei and C. affinis and fishes. Its diet also included small quantities of cephalopods, amphipods, hermit crabs and crabs. Individuals between 35 cm and 45 cm SL mainly consumed shrimps. The portion of shrimps decreased with increasing fish size, and this decrease was paralleled with increased consumption of fishes and cephalopods. In this study we found Syngnathus schlegeli in the stomach contents of many Pacific cod specimens. S. schlegeli is a typical seagrass fish species which inhabits in seagrass beds, This fact means that Pacific cods stay in the seagrass beds during spawning period. Therefore migration of Pacific cod to coastal waters off Gadeok-do during spawning period seems to be a survival strategy for its larvae and small juveniles to stay in seagrass beds which provide with abundant foods and shelters to many commercial fish species.