• Journal of fish pathology
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• v.19 no.3
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• pp.207-214
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• 2006

Diagnostic monitoring in fish farms with land-based tanks and net cases was conducted in eastern, western, southern and Jeju island of Korea for the summer period from 2000 to 2006. Total 3,518-fish samples of marine and freshwater fishes in 25 fish species were tested for pathogens. Fish species tested were olive flounder (Paralichthys olivaceus), fleshy prawn (Fenneropenaeus chinensis Osbeck), black rockfish (Sebastes schlegeli), rock bream (Oplegnathus fasciatus), red sea bream (Pagrus major), black seabream (Acanthopagrus schlegeli), sea bass (Lateolabrax japinicus), gray mullet (Mugil cephalus), rainbow trout (Onchorhynchus mykiss) and others. The infection rates by bacterial pathogens in the years of 2000, 2001, 2002, 2003, 2004, 2005 and 2006 were 22.4%, 34.5%, 14.1%, 15.3%, 17.7%, 13.5% and 5%, respectively. The infection rates by parasitic pathogens were 20%, 33.8%, 12.4%, 14.1%, 9.2%, 10.5% and 10.7%, respectively. The infection rates by viral pathogens were 22.4%, 13.5%, 10.3%, 5.4%, 9.7%, 10.2% and 15.8%, respectively. The infection rates by mixed pathogens were 10.3%, 0%, 44.9%, 50.9%, 31.9%, 38.4% and 39.6%, respectively. The rates of mixed infections were very low until 2001. The rates were higher than those of singer infections from 2002 to 2006. During the diagnostic monitoring from 2000 to 2006, the main bacterial pathogens were Vibrio (41.2%) and Streptococcus (28.8%). The infection rate by protozoa (85.7%) mainly including Scuticociliates and Trichodina was highest. The infection rate by viral necrosis virus (VNNV, 42.2%) was the highest of the viral pathogens.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.347-355
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• 1986

The Sonakdong river is very important water source not only for agricultural water of Kimhae field but also for fishery water. Recently the middle and lower areas of the river have the tendency to be heavily contaminated by domestic sewage and agricultural chemicals. Fifty six water samples were collected from 8 stations from July to December in 1985 for the experiment (Fig. 1). To evaluate the water quality, pH, water temperature, electrical conductivity, chloride ion, nutrients ($NO^{-}_{2}-N,\;NO^{-}_{3}-N,\;NH^{+}_{4}-N,\;PO^{3-}_{4}-P,\;SiO_2-Si$), total coliform, fecal coliform, and fecal streptococcus were determined. Range and mean value of the samples were as follows; pH $6.3{\sim}9.4$, 7.91; water temperature $6.1{\sim}34.8^{\circ}C,\;23.88^{\circ}C$; electrical conductivity (from St. A to G) $1.575{\times}10^2{\sim}30.50{\times}10^2{\mu}{\mho}/cm,\;6.57{\times}10^2{\mu}{\mho}/cm$; chloride ion $23.5{\sim}14,300mg/l$, 770.0mg/l; nitrite-nitrogen $0.007{\sim}0.110mg/l$, 0.053mg/l; nitrate-nitrogen $0.001{\sim}1.638mg/l$, 0.649 mg/l; ammonia-nitrogen $0.017{\sim}4.200mg/l$, 0.497mg/l; phosphate-phoshorus $0.011{\sim}0.281mg/l$, 0.086mg/l; and silicate-silicious $2.4{\sim}6.5mg/l$, 4.43mg/l. Electrical conductivity and chloride ion of the station F(Chomanpo) were $2.676{\times}10^2{\mu}{\Omega}cm$ and 123.99mg/l which were lower than those of others. Among the analyzed nutrients, silicate-silicious concentration was the highest through all the samples. The bacterial density of the samples ranged $36{\sim}110,000/100ml$ for total coliform, $15{\sim}46,000/100ml$ for fecal coliform and $3.6{\sim}15,000/100ml$ for fecal streptococcus. The range and the mean of the TC/FC ratio were $3.0{\sim}9.6$, 5.51 and those of the FC/FS ratio were $1.1{\sim}9.2$, 6.19, respectively. On the other hand, fecal coliform was not detected in about $78\%$ of the water samples examined. Composition of coliform was $52\%$ Escherichia coli group, $3\%$ Citrobacter freundii group, $13\%$ Enterobacter aerogenes group and $31\%$ others.

• Pediatric Infection and Vaccine
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• v.7 no.2
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• pp.233-239
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• 2000

Purpose : A great deal of youngsters suffer from otitis media, for which antimicrobials are frequently prescribed. Increased antimicrobial resistance forces physicians to judiciously use antimicrobial agents in treating patients with acute otitis media. There have however been few references with regard to otitis media in Korean children, and authors proceeded investigation to look for the causative agents of otitis media in Korean children and their antimicrobial susceptibility. Methods : The study included 65 patients younger than 15 years old who had been cared at the department of pediatrics and otolaryngology in Hanyang University Hospital from July 1994 to June 1999, and diagnosed of otitis media with otorrhea which contained microorganisms isolated in otorrhea culture. The medical records were reviewed for demographic data, isolated organisms and their antimicrobial susceptibility. Results : Among 65 patients, 37(57%) were boys and 28(43%) girls. Distribution of the patients was reciprocal to the age of the patients; 27 patients(41.5%) were younger than 1 year old, 24(36.9%) were 1 to 3 years old with the average of 2.9 years of age. Staphylococus aureus was isolated in 32 patients(49.2%), Streptococcus pneumoniae in 19 patients(29.2%) Haemophilus influenzae in 9 patients(13.8%), Streptococcus oralis in 3 patients(4.6%), Moraxella catarrhalis in 1 patient(1.5%). The isolated microorganisms were not different whether patients had cleft lip/palate or not. The antibiotic resistance rates of S. aureus were ${\geq}90%$ to erythromycin, imipenem, cephalothin, and clindamycin, 86.2% to oxacillin, 25% to chloramphenicol, 12.5% to trimethoprim/sulfamethoxazole(TMP/SMX), and 0% to vancomycin and teicoplanin. The antibiotic resistance rates of S. pneumoniae were 71.4% to penicillin and greater than 60% to erythromycin, tetracycline, TMP/SMX, 7.1% to chloramphenicol, and 0% to vancomycin and teicoplanin. The antibiotic resistance rates of H. influenzae were 55% to ampicillin and TMP/SMX, and 0% to chloramphenicol, ceftriaxone, aztreonam, imipenem and ciprofloxacin. Conclusion : With otorrhea culture, the causative organisms of otitis media appear to be S. aureus, S. pneumoniae and H. influenzae. The high antibiotic resistance rates of the isolated organisms should affect the choice of antibiotics in treating patients with otitis media. Prospective investigations utilizing tympanocentesis in microbiologic studies are needed.

• Food Science and Preservation
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• v.23 no.5
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• pp.623-630
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• 2016

Inappropriate storage of fresh-cut onions may result in losses of good quality. To understand storage conditions for shelf-life and quality of fresh-cut onions, The effect of packing type and storage temperature on the quality of fresh-cut onions was evaluated. Onions stored at $0^{\circ}C$ for 2 months were peeled off after removing root and shoot parts. Each three peeled onions were packed in a polyethylene film (PE, $50{\mu}m$) or in a polyethylene/polypropylene film (PE/PP, $100{\mu}m$) with vacuum treatment (70 cmHg) and stored at different temperatures (4, and $10^{\circ}C$) for 21 days. The following analyses were examined to evaluate the quality of fresh-cut onions: microbial population, surface color, titratable acidity and pH, respiration rate, and sensory quality. Fresh-cut onions stored at $4^{\circ}C$ showed less aerobic and coliform bacterial population than those stored at $10^{\circ}C$ during observation periods. Fungal populations of fresh-cut onions packed in PE film stored at $10^{\circ}C$ increased significantly after 13 days. E. coli was not detected in all treatments during whole storage periods. Surface colors of fresh-cut onions were not affected by packing type and storage temperature, however, color difference (${\Delta}E$) of fresh-cut onions in PE/PP film stored at $10^{\circ}C$ was significantly higher than those of other treatments. Titratable acidity of fresh-cut onions was not affected by packing type and storage temperature. However, pH of fresh-cut onions packed in PE film stored at $10^{\circ}C$ increased gradually over the whole storage period. Fresh-cut onions packed in PE film showed higher $CO_2$ and less $O_2$ concentrations at $10^{\circ}C$ than those at $4^{\circ}C$. The sensory quality of fresh-cut onions was significantly affected by packing type and storage temperature after 13 days. Particularly, vacuum treatment in PE/PP film showed better sensory quality than that of PE film package at the same storage temperature. It was concluded that vacuum treatment and storage at $4^{\circ}C$ could be effective to prolong the quality of fresh-cut onions up to 21 days.

• Food Science and Preservation
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• v.24 no.6
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• pp.746-757
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• 2017

This study was performed to evaluate the effect of different freezing conditions and storage periods on physicochemical and microbial characteristics of garlic. Garlics were washed, dried, sliced to 0.3 cm then packed in LDPE+LLDPE film bags. They were treated with still-air freezing at $-20^{\circ}C$ (SAF20), $-40^{\circ}C$ (SAF40) and immersed-liquid freezing at $-40^{\circ}C$ (ILF40). Frozen garlics were stored under frozen storage conditions for 7 months at $-20^{\circ}C$ and quality characteristics were measured monthly during the frozen storage. Freezing rate of garlic was the fastest in ILF 40 (10 min), SAF40 (40 min) and SAF20 (1,600 min) sequentially. In ILF40, drip loss, cutting force, total aerobic bacteria count and pH were the lowest, whereas pyruvic acid and allicin content were the highest (p<0.05) during frozen storage, these results were the most similar characteristics with the fresh garlic. During frozen storage, drip loss, color difference and total organic acid content were significantly fluctuated in SAF20 (p<0.05), while they were not changed in ILF40. Overall, total aerobic bacteria count and pH decreased, cutting force, pyruvic acid and allicin content remained unchanged in all groups. In conclusion, the optimal freezing conditions for garlic with the least quality changes was considered to be ILF40 (immersed liquid freezing), keeping quality characteristics up to 7 months by freezing storage.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.299-304
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• 2014

The dose-response models are important for the quantitative microbiological risk assessment (QMRA) because they would enable prediction of infection risk to humans from foodborne pathogens. In this study, we performed a comprehensive literature review and meta-analysis to better quantify this association. The meta-analysis applied a final selection of 193 published papers for total 43 species foodborne disease pathogens (bacteria 26, virus 9, and parasite 8 species) which were identified and classified based on the dose-response models related to QMRA studies from PubMed, ScienceDirect database and internet websites during 1980-2012. The main search keywords used the combination "food", "foodborne disease pathogen", "dose-response model", and "quantitative microbiological risk assessment". The appropriate dose-response models for Campylobacter jejuni, pathogenic E. coli O157:H7 (EHEC / EPEC / ETEC), Listeria monocytogenes, Salmonella spp., Shigella spp., Staphylococcus aureus, Vibrio parahaemolyticus, Vibrio cholera, Rota virus, and Cryptosporidium pavum were beta-poisson (${\alpha}=0.15$, ${\beta}=7.59$, fi = 0.72), beta-poisson (${\alpha}=0.49$, ${\beta}=1.81{\times}10^5$, fi = 0.67) / beta-poisson (${\alpha}=0.22$, ${\beta}=8.70{\times}10^3$, fi = 0.40) / beta-poisson (${\alpha}=0.18$, ${\beta}=8.60{\times}10^7$, fi = 0.60), exponential (r=$1.18{\times}10^{-10}$, fi = 0.14), beta-poisson (${\alpha}=0.11$, ${\beta}=6,097$, fi = 0.09), beta-poisson (${\alpha}=0.21$, ${\beta}=1,120$, fi = 0.15), exponential ($r=7.64{\times}10^{-8}$, fi = 1.00), betapoisson (${\alpha}=0.17$, ${\beta}=1.18{\times}10^5$, fi = 1.00), beta-poisson (${\alpha}=0.25$, ${\beta}=16.2$, fi = 0.57), exponential ($r=1.73{\times}10{-2}$, fi = 1.00), and exponential ($r=1.73{\times}10^{-2}$, fi = 0.17), respectively. Therefore, these results provide the preliminary data necessary for the development of foodborne pathogens QMRA.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.163-173
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• 2011

The objective of this study was to determine microbiological risk factors in hot pepper farms for the application of good agricultural practices (GAP). Samples were collected from cultivation environments and utensils, plants, workers, and air at 3 hot pepper farms located in Cheongsong, Korea and were tested to detect sanitary indications [aerobic plate bacteria (APC), coliform, and Escherichia coli], foodborne pathogens, and fungi. APC, coliform, and fungi were detected at the levels of 0.7~6.2, 0.2~4.7, and 0.4~4.3 log CFU, respectively, in the three farms. Four (4.4%; l leaf, l irrigation water, and 2 soil) of 90 samples collected were revealed to be E. coli positives. For foodborne pathogens, Staphylococcus aureus was only detected at $1.0log\;CFU/100cm^2$ in the worker's cloth of B farm, and Bacillus cereus was detected at the levels 1.0~2.5 log CFU in the cultivation environments and utensils and worker of B and C farms. However, other pathogens were not detected. The results demonstrated potential microbiological risks for hot pepper cultivated in the farms. Therefore, a management system to minimize the microbial risk such as GAP is required to ensure the safety of hot pepper.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.3
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• pp.223-229
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• 2022

This study was conducted to investigate the effect of packaging methods and sterilization treatment on storability and microbial control in paprika fruits. When treated with chlorine dioxide gas for 3, 6, and 12 hours and cold plasma gas for 1, 3, and 6 hours, and then packed in a carton box and stored in a 8 ± 1℃ chamber for 7 days, chlorine dioxide treated 12 hours and plasma treated 6 hours was prevented the development of E·coli and YM(yeast and mold). Accordingly, the control was treated with chlorine dioxide for 12 hours and plasma for 6 hours, packed using a carton box and 40,000 cc·m^-2·day^-1·atm^-1 OTR film (MAP), and stored in a 8 ± 1℃ chamber for 20 days. Fresh weight loss rate during storage was less than 1% in the MAP treatments, and the visual quality of the MAP treatments was above the marketability limit until the end of storage. There was no difference in the contents of oxygen, carbon dioxide, and ethylene in the film. In the case of firmness, the chlorine dioxide treatments was low, and the Hunter a^* value, which showed chromaticity, was highest in the Plasma 6h MAP treatment. Off-odor was investigated in the MAP treatments, but it was very low. The rate of mold growth on the fruit stalk of paprika was the fastest and highest in the chlorine dioxide treated box packaging treatments, and the lowest in the chlorine dioxide treated MAP treatments at the end of storage. The aerobic count in the pulp on the storage end date was the lowest in the plasma treated box packaging treatments, the lowest number of E·coli in the chlorine dioxide treated MAP treatments, and the lowest yeast & mold in the chlorine dioxide treated box packaging treatments. As a result, for the inhibition of microorganisms during paprika storage, it is considered appropriate to treat plasma for 6 hours before storage regardless of the packaging method.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.4 s.334
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• pp.19-28
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• 2005

In this paper, we proposed a parallel fast 2-D discrete wavelet transform hardware architecture based on lifting scheme. The proposed architecture improved the 2-D processing speed, and reduced internal memory buffer size. The previous lifting scheme based parallel 2-D wavelet transform architectures were consisted with row direction and column direction modules, which were pair of prediction and update filter module. In 2-D wavelet transform, column direction processing used the row direction results, which were not generated in column direction order but in row direction order, so most hardware architecture need internal buffer memory. The proposed architecture focused on the reducing of the internal memory buffer size and the total calculation time. Reducing the total calculation time, we proposed a 4-way data flow scheduling and memory based parallel hardware architecture. The 4-way data flow scheduling can increase the row direction parallel performance, and reduced the initial latency of starting of the row direction calculation. In this hardware architecture, the internal buffer memory didn't used to store the results of the row direction calculation, while it contained intermediate values of column direction calculation. This method is very effective in column direction processing, because the input data of column direction were not generated in column direction order The proposed architecture was implemented with VHDL and Altera Stratix device. The implementation results showed overall calculation time reduced from $N^2/2+\alpha$ to $N^2/4+\beta$, and internal buffer memory size reduced by around $50\%$ of previous works.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.286-292
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• 2016

1, 2-Hexanediol galactoside (HD-gal) has been synthesized from 1, 2-hexanediol (HD), a cosmetic preservative, using recombinant Escherichia coli ${\beta}$-galactosidase (${\beta}$-gal) at the high lactose concentration (300 g/l). To confirm the molecular structure of synthesized HD-gal, NMR ($^1H$- and $^{13}C$-) spectroscopy and mass spectrometry of HD-gal were conducted. $^1H$ NMR spectrum of HD-gal showed multiple peaks corresponding to the galactocyl group, which is an evidence of galactocylation on HD. Downfield proton peaks at ${\delta}_H$ 4.44 ppm and multiple peaks from ${\delta}_H$3.96~3.58 ppm were indicative of galactocylation on HD. Up field proton peaks at ${\delta}_H$ 1.60~1.35 ppm and 0.92 ppm showed the presence of $CH_2$ and $CH_3$ protons of HD. $^{13}C$ NMR spectrum revealed the presence of 21 carbons suggestive of ${\alpha}$- and ${\beta}$-anomers of HD-gal. Among 12 carbon peaks from each anomers, the 3 peaks at dC 68.6, 60.9 and 13.2 ppm were assigned to be overlapped showing only 21 peaks out of total 24 peaks. The mass value (protonated HD-gal, m/z = 281.1601) from mass spectrometry analysis of HD-gal, and $^1H$ and $^{13}C$ NMR spectral data were in well agreement with the expecting structure of HD-gal. For further study, the minimum inhibitory concentrations (MICs) of HD-gal against bacteria will be investigated, and, in addition, cytotoxicity to human skin cells of HD-gal will be examined. It is expected that it will eventually be able to develop a new cosmetic preservative, which have low cytotoxicity against human skin cell and maintains antimicrobial effect.