• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.1060-1067
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• 2006

This study was undertaken to determine the effect of reservoirs on water quality and the distribution of pathogenic and indicator bacteria in a drinking water distribution system (total length 14km). Raw water, disinfected water, and water samples from the distribution system were subjected to physicochemical and microbiological analyses. Most factors encountered at each season included residual chloride, nitrate, turbidity, and phosphorus for heterotrophic bacterial distribution, and hardness, heterotrophic bacteria, sampling site, and DOC (dissolved organic carbon) for bacteria on selective media. No Salmonella or Shigella spp. were detected, but many colonies of opportunistic pathogens were found. Comparing tap water samples taken at similar distances from the water treatment plant, samples that had passed through a reservoir had a higher concentration of heterotrophic bacteria, and a higher rate of colony formation with 10 times as many bacteria on selective media. Based on the results with m-Endo agar, the water in reservoirs appeared safe; however, coliforms and opportunistic pathogenic bacteria such as Pseudomonas aeruginosa were identified on other selective media. This study illustrates that storage reservoirs in the drinking water distribution system have low microbiological water quality by opportunistic pathogens, and therefore, water quality must be controlled.

• Journal of Yeungnam Medical Science
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• 제5권1호
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• pp.69-75
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• 1988

대구시내 6개구에서 각 2개소의 아파트와 각 1개소의 단독주책을 선정하여 총 18개소의 가정상수를 1987년 5월 12일에서 10월 15일 사이에 봄, 여름, 가을 3회에 걸쳐 채취하여 이화학적 및 미생물학적 수질검사를 시행하였다. pH치는 최저 6.80에서 최고 8.10으로 모두 정상범위였으며, 잔류염소치 0.2ppm미만인 경우가 아파트군 16.7%, 단독주택군 5.6%였다. 아질산성 질소양성은 아파트군에서만 2.8%로 나타났다. 일반세균수가 $m{\ell}$당 100개 이상인 경우는 아파트군 11.1%, 단독주택군 11.1%였고, 대장균군의 MPN이 1.8%이상인 경우가 아파트군 27.8%, 단독주택군 33.3%였다. 잔류염소치, 아질산성 질소, 일반세균수 및 대장균군 검사에서 4가지 음용기준에 부적당한 것은 아파트군에서만, 2.7%였고, 3가지 검사에서 부적당한 것이 아파트군 2.7% 단독주택군 5.6%, 2가지 검사에서 부적당한 것이 아파트군 8.3% 단독주택군 5.6%, 1가지 검사에서 부적당한 것이 아파트군 25.0% 단독주택군 22.2%였다. 이화학적 및 미생물학적 검사성적의 상호비교에서 잔류염소치와 일반세균수 사이에, 그리고 대장균균수와 일반세균수 사이에 연관성이 있었다. 아파트의 건립년수가 길수록 수질이 좋지 않은 것으로 관찰되었다.

• 한국물환경학회지
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• 제32권6호
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• pp.600-627
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• 2016

Korea is one of the countries with a large veterinary antibiotics market, although antimicrobial resistance in bacteria is becoming a serious issue in many countries. The Korean government started to take interest in estimating the effects of livestock manure on rivers and agricultural soils and in monitoring of heavy metals, organic pollutants and antibiotics in the ambient water and soil. In this paper, pre-treatment methods to separate the selected antibiotics from solid samples were reviewed. It is essential to select an efficient and appropriate procedure for pre-treatment due to the high proportion of proteins and organics in biosolid samples. Pre-treatment consists of extraction followed by clean-up. Initially, homogenized samples were extracted by sonication, mechanical agitation or pressurized liquid extraction with methanol/acetonitrile/water mixture under acidic/basic conditions depending on the compound. However, aminoglycosides and colistin were extracted with 5% trichloroacetic acid and HCl, respectively. Since the ${\beta}-lactams$ are easily decomposed in acidic and basic conditions, they were extracted in neutral pH. Filtration with a membrane (pore size, $0.2{\mu}m$) or solid phase extraction with HLB and methanol, as eluents, was normally applied for the clean-up. At least, three different pre-treatment procedures should be adopted to screen all the selected antibiotics in solid samples.

• 한국식품저장유통학회지
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• 제4권2호
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• pp.155-162
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• 1997

This work was designed to determine the effect of steaming-Pretreatment on Physicochemical and functional properties of roasted Polygonatum odoratum roots. Steaming treatments led to some reduction in the contents of water solubles, such as total solid, reducing sugar and free-amino nitrogen of the unroasted samples. Moreover, roasting processing caused decrease in reducing sugar and free-amino acid, with increase in total soluble solid and browning color of the samples, which showed the dependence of steaming treatment as well as roasting temperature. Electron-donating ability and nitrite-scavenging ratio of the samples were also highly developed along with roasting processing at 17$0^{\circ}C$ within 35min. Considering the physicochemical and some functional parameters of water extracts of roasted samples, roasting at above 14$0^{\circ}C$ for over 55min or at 17$0^{\circ}C$ for around 35min was recommendable for the higher quality of Polygonatum odoritum tea, which conditions were similarly adapted for both steamed and unsteamed samples.

• 미생물학회지
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• 제44권3호
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• pp.244-250
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• 2008

울산 소재 S회사(S-C)와 U고등학교(U-H)에 설치된 냉온수기를 대상으로 S-C에서 냉수 74개, U-H에서 냉수와 온수 각 36개의 시료를 채수하여 미생물 분포를 조사하였다. 일반세균 농도의 중간값은, S-C 시료에서 53 CFU/ml ($0\sim4,135$ CFU/ml)이었으며, U-H의 경우 냉수에서 80 CFU/ml ($0\sim1,480$ CFU/ml), 온수에서 0 CFU/ml ($0\sim240$ CFU/ml)이었다. S-C 시료의 38%, U-H 냉수 시료의 42%에서 일반세균에 대한 먹는 물 수질기준인 100 CFU/ml을 초과하였으며, 대장균군은S-C의 1개 시료에서 검출되었다. 냉온수기에서 검출되는 미생물의 주요오염 경로를 확인하고자, 2회에 걸쳐 먹는 샘물 용기로부터 각각 6일과 8일 동안 매일 시료를 채수하였으며, 2회 채수는 냉온수기의 꼭지에서도 행하였다. 일반세균 농도의 평균값은, 먹는 샘물 용기에서 1회 33 CFU/ml, 2회 132 CFU/ml이었으며, 냉수 꼭지 시료에서 1,022 CFU/ml로, 냉온수기 꼭지에서 검출되는 대부분의 세균은 먹는 샘물이 수조통과 통로관을 거치면서 오염된 것으로 판단된다. 먹는 샘물 용기를 냉온수기에 연결한 후 시간의 경과에 따른 용기 내 일반세균수의 유의성 있는 증가는 없었다. 임의의 100개 일반세균 집 락을 대상으로 순수배양 후표현형에 따른 동정 시험을 하였으며, 그람양성 3속6종,그람음성 7속7종 등, 모두 10속13종의 세균을 잠정적으로 확인하였다. U-H의 4대 냉온수기 꼭지에서, 그람양성은 전체의 72%이었고, 그람양성의 Micrococcus spp.가 전체의 54%를 차지하여 가장 많았다. Micrococus spp.와 그람음성의 Sphingomonas paucimobilis는4대의 냉온수기 모두에서 분리되었다. 냉온수기의 일반세균은 주로 실내 공기중 미생물로부터 유래하며, 이들 미생물이 냉온수기의 수조통 흑은 통로관에서 생물막 형성에 중요한 역할을 하는 것으로 생각된다.

• Corrosion Science and Technology
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• 제15권4호
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• pp.166-170
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• 2016

The combined process of porous type anodizing and desiccation treatment was applied to improve wettability of A1050 aluminum alloy. The water contact angles of anodized samples were increaseds considerably with desiccation treatment. However, there was no considerable effect of polishing and anodizing time on water contact angle. The corrosion behavior with the treatments was investigated electrochemically. The corrosion resistance of the samples in 3.5 mass% NaCl solutions increased with higher contact angle. Anodized and desiccated samples showed better corrosion resistance than un-desiccated samples around rest potential region.

• 한국식품조리과학회지
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• 제24권6호
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• pp.849-855
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• 2008

DPPH radical scavenging activities were 66.80% by hot water extract and 41.86% by 80% methanol extract. Inhibitions of angiotensin I-converting enzyme (ACE) were 91.09% by hot water extract and 75.20% by 80% methanol extract. In this study, Sulgidduk samples were prepared with 1, 3, 5, and 7% concentrated sweet pumpkin powder (CSPP), and a control were examined for quality characteristics such as moisture content, water activity, color, textural characteristics, and sensory qualities, in order to determine the optimal ratio of CSPP in the formulation. The samples containing CSPP exhibited significantly higher moisture content than the control group. Water activity was not significantly different among the Sulgidduk samples. For the color, the control group presented significantly higher lightness as compared to the samples containing CSPP. The samples containing 1 and 3% CSPP had significantly higher greenness than the samples containing 5 and 7% CSPP. Yellowness increased as the level of CSPP content increased. In terms of textural characteristics, hardness, gumminess, and chewiness were highest at the 1% substitution level, while lowest at the 3% level. The CSPP samples presented significantly higher adhesiveness, springiness, and cohesiveness than the control group. In the consumer acceptance and characteristic intensity rating test, the control group showed significantly higher color and flavor as compared to the CSPP samples. Pumpkin flavor, delicious taste, and off-flavor increased with increasing amounts of CSPP. Softness, overall acceptability, and gumminess were not significantly different among the various samples tested. Sweetness was highest at the 5% substitution level, while lowest at the 1% level. In conclusion, the results indicate that substituting $3{\sim}5%$ CSPP to Sulgidduk is optimal, providing good DPPH radical scavenging activity and inhibition of ACE as well as reasonably high overall acceptability.

• Environmental Analysis Health and Toxicology
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• 제29권
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• pp.19.1-19.10
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• 2014

Objectives Lysosome is the cell-organelle which is commonly used as biomonitoring tool in environmental pollution. In this study, the lysosomal proteomic of the yeast Saccharomyces cerevisiae was analyzed for utilization in the detection of toxic substances in mine water samples. Methods This work informs the expression of lysosomal proteomic in yeast in response with toxic chemicals, such as sodium meta-arsenite and tetracycline, for screening specific biomarkers. After that, a recombinant yeast contained this biomarker were constructed for toxic detection in pure toxic chemicals and mine water samples. Results Each chemical had an optimal dose at which the fluorescent protein intensity reached the peak. In the case of water samples, the yeast showed the response with sample 1, 3, 4, and 5; whereas there is no response with sample 2, 6, and 7. Conclusions The recombinant yeast showed a high ability of toxic detection in response with several chemicals such as heavy metals and pharmaceuticals. In the case of mine water samples, the response varied depending on the sample content.

• Environmental Analysis Health and Toxicology
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• 제21권3호
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• pp.283-289
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• 2006

In recent years, there has been an increase in consumer demand for bottled waters. There is a perception that consumption of natural mineral water represents a healthy life style and that these products are relatively safe. In this study, the microbiological quality of 39 samples of bottled water, purchased from retail store in Korea, was investigated during the 2005. Applying pour plate method, the 1 mL of water samples were analyzed for the presence and enumeration of total general bacteria and Pseudomonas spp.. Nineteen samples representing 9 brands of bottled water contained general bacteria ($1.54{\times}10^2$ CFU/mL). In addition four samples contained Pseudomonas spp. and Camamonas acidovorans. The susceptibility of the strains tested against 25 antimicrobial agents, Pseudomonas fluorescens were resistant to Lincomycin, Amoxacilin/Clavulanic acid and Cefazolin (> $100{\mu}g/mL$). Also Comamonas acidovorans were intermediate to Cephalothin and resistant to Cefoperazone.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.582-588
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• 1995

The preconcentration and determination of trace Cd(Ⅱ), Cu(Ⅱ), Pb(Ⅱ), Mn(Ⅱ) and Zn(Ⅱ) in water samples were studied by the precipitate flotation using La(OH)3 as a coprecipitant. The analytes were quantitatively coprecipitated by adding 3.0 mL of 0.1 M La(Ⅲ) solution in a 1,000 mL water sample and adjusting the pH to 9.5 with NaOH solution. After the addition of the 1:8 mixed surfactant solution of each 0.1% sodium oleate and sodium lauryl sulfate, the solution was stirred with a magnetic stirrer for 10 minutes. The precipitates were floated to the surface by bubbling with nitrogen gas and collected in a small sampling bottle. The precipitates were dissolved in nitric acid and then the solutions were diluted to 25.00 mL with a deionized water. The analytes were determined by flame atomic absorption spectrometry. This procedure was applied to the waste water analysis. This technique was simple, convenient and especially rapid for the analysis of a large volume of sample. And also, from the recoveries of better than 92% which were obtained from real samples, this method could be judged to be applicable to the preconcentration and quantitative determination of trace elements in water samples.