• Environmental Engineering Research
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• 제20권4호
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• pp.403-409
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• 2015

This study aims to investigate the use of a floating media filter (FMF) to eliminate waterborne microorganism in treated domestic wastewater for reuse in agriculture. A conventional sand filter (SF) was used concurrently to compare treated water quality. The total/fecal coliforms and somatic coliphage were employed as fecal indicators. The result showed that the FMF was fed with 3 times higher infiltration rate ($15m^3/m^2.h$) than that in the SF ($5m^3/m^2.h$), in which both filters gave similar coliform removal at 6 hours operation. The somatic coliphage elimination tended to increase with operational time for the FMF while that of the SF showed decreasing trend. When a 24 hour continuous operation was applied for the FMF, it showed better removal of somatic coliphage (78%), fecal coliforms (60%) and total coliforms (56%) than that of 6 hour operation. In conclusion, the FMF gave better performance than the SF did by producing a good quality of treated water for agriculture in terms of waterborne microorganisms including turbidity and suspended solids.

• 대한영양사협회학술지
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• 제4권2호
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• pp.235-244
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• 1998

Hand washing is an important component of hygiene program for food handlers. Hands can be a source of direct or indirect contamination of foods with pathogenic microorganisms. In this study, the effectiveness of hand washing methods and the use of 70% alcohol solution against transient skin bacteria was tested in an university foodservice facility. 70% alcohol solution is sprayed for 5 seconds automatically when hands are placed in the dispenser. Samples were taken using swab technique in meat cutting area, vegetable trimming area, and vegetable cutting area: before and after washing hands according to planned methods, and after being sprayed with 70% alcohol solution after washing hands. The bacteriological analysis of total plate counts, coliform, fecal coliform of food handlers' hands was done. Statistical data analysis was completed with Mann-Whitney U test and Kruskal-Wallis model using the SPSS program. The levels of initial contamination of workers' hand were significantly different by the work areas($x^2$=9.156, p<0.01). Workers in the vegetable trimming area had more heavily soiled hands than in the other work areas. Mean of TPC counts and coliform was 8.97×$10^5$ CFU/12.4$cm^2$, 2.93×$10^2$ MPN/12.4$cm^2$ respectively, but fecal coliform was not detected. Transient bacteria were removed from hands after washing and using 70% alcohol solution but were not removed completely. Mean reduction percentage in TPC varied among work areas and ranged from 93.19% to 94.99%, and in coliforms from 97.31% to 100%. A significant difference in TPC was found between before and after hand disinfection (Z=-2.714, p<.01) and between standardized hand washing procedures and un-standardized hand washing procedures(z=-2.301, p<.01). Subjects using the hand sanitizer showed a great elimination of TPC(99.45% reduction), but this effect was valid only after following proper washing procedures. Based on the results, the most effective hand washing method was recommended as the combination of the standardized hand washing procedure with warm-water and use of the 70% alcohol solution. The results can be used to develop hand hygiene programs and training strategies for enhancing hand hygiene practices for food handlers in foodservice operations.

• 한국수산과학회지
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• 제12권4호
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• pp.261-266
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• 1979

부산 근교에서 생산되는 고등 소채류에 대한 세균오염상태를 파악하고 세척, blanching등 처리방법에 따른 세균 제거율과 IMViC system에 의한 대장균군 동정시험 결과를 요약하면 다음과 같다. 1. 엽채류는 과채류에 비하여 분편소대장균의 오염도가 높았다. 2. 수도수로 세척했을 때 생균수 제거율에 있어서는 약 $70\%$, 엽채류에 있어서는 약 $20\%$ 있다. 3. 엽채류를 시판 서첵제로 세척했을 때 생균수 제거율을 약 $80\%$ 수도수로 세척했을때보다 $3\~4$배의 세척 효과가 없었다. 4. 2배의 끊는물에서 1분간 blanching했을 때 생균수 잔재율은 $0.1\%$ 이하있다. 5. 대장균군의 조성은 Eschrichia colr group $18\%$ Citrobacter freundii group $22\%$, Klebsiella aerogenes group $60\%$였으며 이중 Escherichia coli type I 이 $16\%$를 차지하였다. 6. 대장균군 확정시험 배지인 BGLB의 신선성은 약 $80\%$ 였다.

• 한국산학기술학회논문지
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• 제21권7호
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• pp.277-284
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• 2020

본 실험은 모돈 사료 내 Portulaca oleracea L.(POL)의 첨가가 번식성적, 혈액성상, 면역반응 및 분 중 미생물에 미치는 영향을 구명하기 위해 수행하였다. 본 실험을 위해 총 20두의 모돈(Landrace×Yorkshire; 229.2±1.15 kg)을 공시하였으며, 개시체중에 기반하여, 2처리 10반복, 반복당 1두씩 완전임의 배치하였다. 실험 처리구는 옥수수-대두박 기초사료를 대조구로 하여 기초사료 내 POL을 0.05% 첨가한 처리구가 포함되었으며, 분만 직후부터 포유기간 동안 수행하였다. 사료 내 POL을 첨가하였을 때, 모돈의 체중, 등지방두께 및 번식성적에서는 유의적인 차이가 나타나지 않았다(p>0.05). 혈액성상에서 사료 내 POL의 첨가하였을 때, 모돈의 림프구가 유의적으로 감소하는 것으로 나타났다(p<0.05). 또한, 면역반응에서 사료 내 POL을 첨가하였을 때 포유모돈의 혈 중 IL-1β의 수치는 유의적으로 감소하였으며(p<0.05), IgG는 증가하는 경향이 관찰되었다(p=0.051). 분 중 미생물에서는 POL 처리구에서 포유모돈의 coliforms이 감소하는 경향을 확인하였다(p=0.063). 본 실험의 결과들을 종합해보면, 사료 내 POL의 첨가는 번식성적에 부정적인 영향을 미치지 않으며, 모돈의 혈액성상, 면역반응 및 분 중 미생물에 긍정적인 효과를 미치는 것을 시사한다.

• 한국수산과학회지
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• 제44권6호
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• pp.622-629
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• 2011

We investigated the effect of the discharged water from Bong Stream, which is located in the drainage area of Gangjinman area on the bacteriological water quality in the coastal area after rainfall events. Following 12.5 mm of rainfall, water discharged from Bong Stream had a very limited effect on bacteriological water quality in adjacent area and the affected area did not extend to the designated area. On the other hand, after 23 mm rainfall, the density of fecal coliform at stations located in the designated area was higher than at stations located in the adjacent area. The degree of bacteriological contamination at the surveyed stations in the coastal area after rainfall events did not show a relationship with distance from the shoreline. These results indicate that the direction of spread and the range of contaminants from the drainage area were affected by tides at the time of the survey. Therefore, a detailed survey of the effects of tides on the diffusion characteristics of the contaminants from Bong Stream is needed to establish a proper management plan for the surveyed area.

• 한국농공학회논문집
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• 제57권3호
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• pp.1-7
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• 2015

The objective of this study was to compare fecal microbes survival in soil between compost surface application and soil incorporation. The survival experiment was conducted in six styrofoam beds ($510{\times}325{\times}305(mm)$ in size) filled with sandy loam soil. A half of six boxes were received by compost surface application, while the other half were treated with compost-soil mixture. Duplicated surface and surbsurface soil (20 cm depth) samples were collected at various interval up to 50 days and analyzed for the determination of fecal coliforms and E. coli numbers. As expected, surface applied beds demonstrated two to three magnitudes order greater in both the study microorganisms as compared to soil incorporated beds. Microbial inactivation rate of soil surface was twice as great as subsurface soil condition probably due to exposure to sun light and environmental conditions including moisture loss. When rainfall occurred, microbes on the surface were transported into soil along with water movement. It was concluded that surface compost application may be easier to apply but pose higher risk of human exposure to microbes. Winter compost application may be favorable in alleviating health risk by giving some time for inactivation compared to spring application.

• Asian-Australasian Journal of Animal Sciences
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• 제31권8호
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• pp.1308-1314
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• 2018

Objective: Gut health improvements were monitored with respect to growth performance, diarrhea incidence, fecal bacterial population and intestinal morphology of suckling pigs orally supplemented with live Lactobacillus salivarius (L. salivarius) oral suspensions and challenged with $F4^+$ enterotoxigenic Escherichia coli (ETEC). Methods: Two groups of newborn pigs from 18 multiparous sows were randomly designated as non-supplemented (control: n = 114 piglets) and L. salivarius supplemented groups (treatment: n = 87 piglets). Treatment pigs were orally administered with 2 mL of $10^9$ colony-forming unit (CFU)/mL L. salivarius on days 1 to 3, then they were orally administered with 5 mL of $10^9CFU/mL$ L. salivarius on days 4 to 10, while those in control group received an equal amount of phosphate buffered saline solution. On day 24 (2 weeks post supplementation), one pig per replicate of both groups was orally administered with $10^8CFU/mL$ $F4^+$ ETEC, then they were euthanized on day 29 of experiment. Results: Results revealed that pigs in treatment group had a statistically significant increase in average daily gain, body weight and weight gain, and tended to lower diarrhea throughout the study. Numbers of Lactobacillus population in feces of treatment pigs were higher than control pigs, especially on day 10 of study. Numbers of total bacteria in intestinal contents of control pigs were also increased, but not Coliform and Lactobacillus populations. Histological examination revealed statistically significant improvements of villous height and villous/crypt ratio of duodenum, proximal jejunum and distal jejunum parts of treatment pigs compared with controls. Duodenal pH of treatment group was significantly decreased. Conclusion: Oral supplementation of live L. salivarius during the first 10 days of suckling pig promoted growth performance and gut health, reduced diarrhea incidence, increased fecal Lactobacillus populations and improved intestinal morphology.

• 한국어병학회지
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• 제4권1호
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• pp.23-30
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• 1991

부산인구의 약 23.5%인 110만명 이상이 거주하는 수영천으로 인하여 도시하수, 가정폐수 등의 오염의 영향을 직접받는 수영만에서 동계동안(1990년 11월, 12월, 1991년 1월, 2월) 대장균군의 분포를 조사하고 여기에 관련된 환경요인을 분석한 결과를 아래와 같이 요약하였다. 염분은 16.84~34.93%의 범위였으며, 용존산소는 동계임에도 불구하고 수영만 하구부근에서는 $1m{\ell}/{\ell}$ 이하의 분포를 보였으며, COD는 0.48~5.06ppm, 영양염류중 아질산염은 $0.42{\sim}18.82{\mu}g-at/{\ell}$, 질산염 $0.5{\sim}53.23{\mu}g-at/{\ell}$, 암모니아는 $3.73{\sim}56.16{\mu}g-at/{\ell}$, 규산염은 5.18~147.29범위였다. 조사기간 대장균군수의 변화는 $1.1{\times}10^2{\sim}2.4{\times}10^5/100m{\ell}$, 분변성 대장균군은 $1.7{\times}10{\sim}3.5{\times}10^4/100m{\ell}$였으며, TC/FC비는 1.73~58.49로 크게 나타났다. 분리된 117개 균주중 E. coli 가 68.4% 로 가장 우점하였으며, 그 중 E. coli I type이 97.47%로 가장 많은 부분을 차지하였다.

• 한국수산과학회지
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• 제11권1호
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• pp.5-8
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• 1978

순환여과수조에 있어 수질 오염의 지표로서 대장균군의 수적인 변동을 측정하였다. 세균의 오염은 주로 어류의 먹이와 배설물 그리고 새로 교환되는 사육수의 기오염도에 원인이 있었다. 수조내의 세균량은 수질의 물리화학적인 요인에 의해서 조절되었으며, 이러한 요인들 중에서는 pH가 주된 것이었다. 수온 $20^{\circ}C$에 pH가 $5\~6$ 이하로 낮아질 경우에는 세균의 급격한 번식은 없었다. 수온이 $30^{\circ}C$ 이상 일 때 세균의 성장은 pH에 관계없이 현저하게 감소하였으며, 세균군은 그 이하의 온도에서 활발히 성장하는 것처럼 보였다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.421-424
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• 2002

Deterministic and probabilistic approaches to the design of ultraviolet (UV) disinfection system for water reclamation are reviewed and discussed. The high inactivation of TC, FC and E. coli by UV disinfection was demonstrated and the inactivations of TC, FC and E. coli were 97%, 98% and 99%, respectively. Within the range of 0.3-4.5mWs/cm, the effect of UV does on the inactivation ratio was not observed. However, in the highest wattage of UV lamp, 39W, the inactivation ratio of TC, FC and E. coli was 100%, regardless of the UV does so the UV density was more effective on inactivation ratio of TC, FC and E. coli rather than UV does. Under the 0.4 mWs/cm and 16W of UV lamp, the effect of dissolved organic matter and turbidity on the inactivations of TC, FC and E. coli could not be observed in this study within the range of 0-60mg/L and 0-40 NTU respectively.