• 농업생명과학연구
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• 제44권2호
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• pp.7-15
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• 2010

이 연구는 2009년 1월부터 9월까지 총 4회(1월, 4월, 7월 9월) 사천만에서 해수와 표층퇴적물의 세균학적 이화학적 특성을 조사한 것이다. 조사기간 중에 수온은 $5.3{\sim}24.9^{\circ}C$(평균 $17.7{\pm}0.4^{\circ}C$), 투명도는 1.4~2.5m(평균 $1.8{\pm}0.5m$), 부유물질 농도는 16.2~35.8mg/L(평균 $24.2{\pm}2.2mg/L$), 화학적산소요구량 (COD)는 $1.42{\sim}3.29mgO_2/L$(평균 $2.06{\pm}0.55mgO_2/L$), 용존산소(DO)는 6.7~9.5mg/L(평균 $7.9{\pm}0.6mg/L$)로 각각 조사되었다. 대장균군과 분변계대장균의 검출 범위는 <1.8~7,900 MPN/100mL (GM 214.7 MPN/100mL)과 <1.8~330 MPN/ 100mL (GM 9.7 MPN/100mL)로 각각 나타났다. 대장균군은 시료의 75.0%, 분변계대장균은 57.1%가 각각 양성을 나타내었다. 대장균군에 대한 분변계대장균의 양성율은 76.2%로 나타났다. 조사기간 중에 사천만에서의 표층퇴적물의 수분함량, 강열감량, COD 및 AVS의 평균값은 $53.28{\pm}2.58%$, $9.38{\pm}0.42%$, $14.23{\pm}3.36mgO_2/g$, $0.09{\pm}0.07mgS/g$로 각각 조사되었다.

• 한국식품과학회지
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• 제36권1호
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• pp.162-167
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• 2004

최소 가공식품(minimally processed food)의 형태로 살균과정 없이 시장에서 유통되어 섭취되는 채소류들은 미생물 오염에 무방비로 노출되어 식품 안전상 큰 문제가 되고 있다. 본 연구에서는 국내 유통 중인 양배추를 표본으로 하여 이에 잔존하고 있는 aerobic mesophilic bactcria, total coliforms, E. coli, lactic acid bacteria, 그리고 yeasts&molds로 대표되는 미생물 오염도를 조사하였다. 또한 chemical sanitizer chlorine, ethanol, 그리고 hydrogen peroxide를 단독으로 혹은 조합하여 이들 균에 대한 살균효과를 비교하였다. 본 실험결과를 종합해 볼 때 물 세척은 초기 균수를 $0.3-1.2\;log_{10}\;CFU/g$ 감소시켰으며 chlorine(CL), ethanol(ET), hydrogen peroxide(HP) 단독처리는 물보다 살균효과가 컸으나 이들 2가지씩의 조합보다는 효과가 적었다. 이들 세 가지 조합인 CEH로 처리하였을 경우 총 호기성균은 $4\;log_{10}\;CFU/g$, 대장균은 $3\;log_{10}\;CFU/g$, 유산균은 $2\;log_{10}\;CFU/g$, 효모/곰팡이는 $1\;log_{10}\;CFU/g$ 감소로 다른 조합의 세척 방법보다 효과적인 미생물 살균효과를 보였다. 따라서 CEH 조합 살균 소독제 처리는 양배추 등 야채류의 미생물 오염을 감소시킬 수 있는 좋은 제어법으로 활용될 것으로 판단되어진다.

• 한국식품위생안전성학회지
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• 제16권3호
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• pp.241-246
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• 2001

서울시를 비롯한 6개 도시의 음식점과 활어를 판매하는 어시장 등에서 활어조에 사용하는 해수에 대하여 병원성 비브리오균의 분포, 이화학적특성 및 위생지표세균 등 환경인자와의 관계를 비교하였다. 시험해수에서 전염병균인 Vibrio cholerae O1은 전혀 검출되지 않았고, V. parahaemolyticus는 가장 빈번한 검출되었는데 검출율은 69.2%이었다. 그리고 V. vulnificus 및 V. cholerae non-O1 등 병원성 비브리오균이 검출된 활어조의 해수는 그렇지 않은 해수에 비하여 수온과 탁도는 높았고, 염분과 pH는 낮았으며 생균수, 대장균군 및 분변계 대장균이 휠씬 높게 검출되어 이러한 환경인자들과의 관련성이 시사되었다.

• Preventive Nutrition and Food Science
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• 제12권3호
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• pp.167-172
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• 2007

This study was conducted to determine the effect of hygienic processing (HP) on the reduction of microorganisms during manufacturing of saengshik with two vegetables (carrots and cabbage) and two grains (barely and glutinous rice) compared to general processing (GP). For GP, distilled water was used for washing raw materials and equipment. For HP, aqueous ozone (3 ppm) in combination with 1% citric acid and 70% alcohol were used for washing raw materials and the equipment, respectively. In carrots, after cutting, total aerobic bacteria (TAB), yeast and mold (YM) and coliforms were significantly increased to 5.19, 8.04 and 2.08 ($log_{10}$ CFU/g), respectively (p<0.05). Washing effectively reduced the increased microorganisms from cross contamination during cutting, but cross contamination increased with subsequent GP drying and milling procedures to 8.56, 8.27 and 3.71 ($log_{10}$ CFU/g) for TAB, YM and coliforms, respectively (p<0.05). On the other hand, HP washing of carrots with 3 ppm ozone in combination with 1% citric acid showed higher antimicrobial effect than GP washing, significantly decreasing the number of microorganisms (p<0.05). Further cross contamination did not occur through drying and milling due to cleaning the equipments with 70% alcohol prior to processing. After milling, the number of TAB, YM and coliforms were significantly decreased to 3.89, 4.47 and not detectable level ($log_{10}$ CFU/g), respectively (p<0.05). Similar results were observed in cabbage and grains. During storage for two months at different temperatures (22 or $4^{\circ}C$), there were no changes in numbers of spoilage microorganisms in the packaged saengsik after either processing. This suggests the importance of HP for the reduction of microorganisms during saengsik production, and demonstrates the effectiveness of disinfection at each processing stage in minimizing contamination levels to enhance microbial safety of saengshik products.

• 한국환경보건학회지
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• 제37권4호
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• pp.289-297
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• 2011

Objectives: To estimate the microbial contaminant load discharged from livestock farms, we randomly selected livestock farmers of cattle, swine, and fowl and collected bacterial strains from domestic animals' feces and compost samples. Recently, as multi-antibiotic-resistant bacteria and super bacteria showing resistance to a variety of antibiotics have been reported one after another, the ecological and health hazard of antibiotic-resistant bacteria is emerging as an important issue. Methods: Monitored indicator microorganism constituents were totak coliform (TC), fecal coliform (FC), and aerobic bacteria. The multi-antibiotic-resistant bacteria were identified from investigated indicator microorganisms by 16S rRNA sequencing. Results: By microbiological analysis, the largest population of aerobic bacteria ($1.5{\times}10^5$ CFU/g) was found in cattle fecal compost, and total coliforms ($1.1{\times}10^7$ CFU/g) and fecal coliforms ($1.0{\times}10^5$ CFU/g) were found primarily in swine fecal compost, while the lowest population was found in fowl fecal compost. Among the 67 strains separated from aerobic bacteria, five strains expressing high antibiotic resistance were selected in each sample. We found the multi-antibiotic resistant strains to be Shigella boydii, Staphylococcus lentus, Acinetobacter sp. and Brevibacterium luteolum. Conclusions: These results suggest that increasing numbers of multi-antibiotic-resistant bacteria in the environment have a close relation to the reckless use of antibiotics with livestock.

• 한국수산과학회지
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• 제41권3호
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• pp.155-162
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• 2008

The seawater in the Taean area was surveyed to evaluate the conditions of the bay and compliance with the bacteriological criteria for a designated area for shellfish production for export. Samples of seawater were collected monthly at 34 sampling stations established in the survey area from January 2002 to December 2004. The bacterial density in the coastal area close to a pollution source located to the northeast of the survey area was higher than in the open sea to the west. The bacteriological counts in the water did not change with 16.5mm of rainfall, but increased abruptly after 65.4mm of rainfall. The total coliform and fecal coliform most probable numbers (MPNs) of 1,224 seawater samples in the survey area were <1.8-2,400 and <1.8-790 MPN/100 mL, respectively. The geometric mean and estimated 90th percentile of total coliforms were 1.9-3.4 and 2.7-26.3 MPN/100mL, respectively, and for fecal coliforms were <1.8-2.6 and 1.8-12.0 MPN/100mL, respectively. The bacteriological water quality in the Taean seawater area met the National Shellfish Sanitation Program criteria for an approved area and the Korea Shellfish Sanitation Program criteria for a designated area for shellfish production for export.

• 농업과학연구
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• 제42권3호
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• pp.201-205
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• 2015

The experiment was conducted to evaluate the effects of pathogenic Escherichia coli on diarrhea, growth performance, and blood profile of weaned pigs. A total of 48 pigs were used and housed in individual pens of disease containment chambers for 16 d (4 d before and 12 d after the first challenge [d0]). The treatments were with or without the pathogenic E. coli challenge (F-18 E. coli strain; heat-labile, heat-stable, and Shiga-like toxins). Pigs were orally inoculated with a dose of $10^{10}cfu$ E. coli per 3 mL PBS daily for 3 days. The common nursery diet and water were available at all times. The ADG, ADFI, G:F, diarrhea score, ratio of fecal ${\beta}$-hemolytic coliforms from total coliforms (RHT), and blood profile were measured. The pathogenic E. coli reduced (P < 0.05) ADG from d0 to 6 (117 vs. 297 g/d) and from d0 to 12 (377 vs. 238 g/d) compared with the control. Meanwhile, the pathogenic E. coli increased (P < 0.05) diarrhea score (average 3.4 vs. 1.4) and RHT (average 82 vs. 11%) on d3, 6, and 9 and the number of white blood cells (17.59 vs. $13.48{\times}10^3/{\mu}L$) on d6 compared with the control. No differences were found on ADFI and others in the blood profile (total protein and hematocrit). In conclusion, pathogenic E. coli used in this experiment successfully caused mild diarrhea, increased number of white blood cells, and adversely affected growth rate of weaned pigs.

• 한국토양비료학회지
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• 제50권6호
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• pp.538-546
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• 2017

The occurrence of various pathogenic microorganisms on farms is a concern if they are able to contaminate fresh produce, which provides entry into the food supply. This study was undertaken to assess the microbiological quality and prevalence of pathogens in Chinese cabbage cultivated soil in Korea. A total of 57 Chinese cabbage cultivated soils were collected in 4 locations in Korea from February to August 2017. The soils were analyzed for the presence of total aerobic bacteria, Escherichia coli, coliforms, Salmonella spp., Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus. The total aerobic plate counts in soils were in the range of 5.7 to $8.7log\;CFU\;g^{-1}$. The coliforms and E. coli were detected in 39 and 8 out of 57 soil samples, respectively, in the range of 1.1 to $6.3log\;CFU\;g^{-1}$ and 0.7 to $4.0log\;CFU\;g^{-1}$. Salmonella spp., E. coli O157:H7, L. monocytogenes, and S. aureus were not detected from any samples. Results from these studies may help control the spread of bacterial species such as E. coli and Salmonella spp. through the farm environment.

• 한국농공학회논문집
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• 제61권3호
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• pp.67-76
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• 2019

The objectives of this study were to analyze trends of water pollutants and to evaluate the achievement of water quality standards by subbasins in the Han River. The trends of 40 water pollutants at 232 water quality measurement points were analyzed. Chemical oxygen demand (COD), Total organic carbon (TOC), Total coliforms (TC), et cetera were found to be worsening trend. For evaluation of achievement, we evaluated water quality arithmetic mean with river environment standards and human health standards at representative points of the subbasin. Biochemical oxygen demand (BOD), TOC, Total phosphorus (T-P), Fecal coliforms (FC), TC exceeded water quality standards, and water quality of human health standards was all satisfied. So, we prioritized pollutants. If pollutants exceed water quality standards or were worse, they were classified first pollutants. Although BOD and T-P are first pollutants because of water quality standards excess, they are continuously improved. Also, it is better to maintain current status because water quality management system of BOD and T-P is well prepared. Meanwhile, TOC, TC, and FC exceed water quality standards. Furthermore, they were worse gradually, but there is a lack of management systems such as water quality standards of the effluence facilities. Therefore, it is necessary to supplement the system. The results of this study can be used as primary data for the establishment of water quality standards and selection of management pollutants.

• 상하수도학회지
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• 제37권5호
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• pp.281-288
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• 2023

This study was performed to evaluate the pollutants removal characteristics of two types of RBFs(Riverbank filtration, Riverbed filtration) intake facilities installed in Nakdong River and in Hwang River respectively. The capacity of each RBF is 45,000 m³/d for riverbank filtration intake facility and 3,500 m³/d for riverbed filtration intake facility. According to data collected in the riverbank filtration site, removal rate of each pollutant was about BOD(Biochemical Oxygen Demand) 52%, TOC(Total Organic Carbon) 57%, SS(Suspended Solids) 44%, Total coliforms 99% correspondingly. Furthermore, Microcystins(-LR,-YR,-RR) were not found in riverbank filtered water compared to surface water in Nakdong River. DOC(Dissolved Organic Carbon) and Humics which are precursors of disinfection byproduct were also reported to be removed about 59% for DOC, 65% for Humics. Based on data analysis in riverbed filtration site in Hwang River, removal rate of each contaminant reaches to BOD 33.3%, TOC 38.5%, SS 38.9%, DOC 22.2%, UV254 21.2%, Total coliforms 73.8% respectively. Additionally, microplastics were also inspected that there was no obvious removal rate in riverbed filtered water compared to surface water in Hwang River.