• 제목/요약/키워드: microbial contaminants

검색결과 92건 처리시간 0.025초

마른김(Pyropia spp.) 가공 공정 경과에 따른 미생물 오염도 분석 (Analysis of Microbial Contaminants and Microbial Changes during Dried-laver Pyropia spp. Processing)

  • 권기언;류대규;정민철;강은혜;장유미;권지영;김정목;신일식;김영목
    • 한국수산과학회지
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    • 제51권1호
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    • pp.8-14
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    • 2018
  • We investigated the levels of microbial contaminants and microbial hazards during dried-laver processing. We analyzed 321 samples obtained from 18 dried-laver Pyropia spp. manufacturing facilities, including water, swab-, and processing samples as well as final products. The levels of microbial contaminants, including viable cell counts (VCC) and coliform bacteria, increased as processing progressed. The sanitary indicator bacterium, Escherichia coli, was not detected in the final products although VCC levels were high, generally exceeding 5 log CFU/g. We also investigated changes in microbial contaminants at each processing step. Both VCC and total coliform dramatically increased after 4 days of continuous processing, indicating that microbial contaminants originated, mainly, from cross contamination during processing.

Microbial Metal Transformations

  • Gadd, Geoffrey M.
    • Journal of Microbiology
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    • 제39권2호
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    • pp.83-88
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    • 2001
  • There is considerable interest in how microbiological processes can affect the behaviour of metal contaminants in natural and engineered environments and their potential for bioremediation. The extent to which microorganisms can affect metal contaminants is dependent on the identity and chemical form of the metal and the physical and chemical nature of the contaminated site or substance. In general terms, microbial processes which solubilize metals increase their bioavailability and potential toxicity, whereas those that immobilize them reduce bioavailability. The balance between mobilization and immobilization varies depending on the metal, the organisms, their environment and physico-chemical conditions.

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대표적 4개 오염지역의 수리지질 특성과 미생물학적 연구

  • 고경석;김재곤;조경숙;이상돈;염병우
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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    • pp.164-167
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    • 2004
  • To investigate the chemical and microbiological characteristics of groundwater and surface waters in contaminated sites, hydrochemical and microbial community analysis were executed. Different indigenous bacteria were observed at 4 contaminated sites and this is considered to decompose the contaminants of groundwater. The research results showed the close relationship between hydrochemistry and microbial characteristics and those are used for the information of natural attenuation and enhanced bioremediation.

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Effects of Metal and Metalloid Contamination on Microbial Diversity and Activity in Agricultural Soils

  • Tipayno, Sherlyn C.;Chauhan, Puneet S.;Woo, Sung-Man;Hong, Bo-Hee;Park, Kee-Woong;Chung, Jong-Bae;Sa, Tong-Min
    • 한국토양비료학회지
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    • 제44권1호
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    • pp.146-159
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    • 2011
  • The continuous increase in the production of metals and their subsequent release into the environment has lead to increased concentration of these elements in agricultural soils. Because microbes are involved in almost every chemical transformations taking place in the soil, considerable attention has been given to assessing their responses to metal contaminants. Short-term and long-term exposures to toxic metals have been shown to reduce microbial diversity, biomass and activities in the soil. Several studies show that microbial parameters like basal respiration, metabolic quotient, and enzymatic activities, including those of oxidoreductases and those involved in the cycle of C, N, P and other elements, exhibit sensitivity to soil metal concentrations. These have been therefore, regarded as good indices for assessing the impact of metal contaminants to the soil. Metal contamination has also been extensively shown to decrease species diversity and cause shifts in microbial community structure. Biochemical and molecular techniques that are currently being employed to detect these changes are continuously challenged by several limiting factors, although showing some degree of sensitivity and efficiency. Variations and inconsistencies in the responses of bioindicators to metal stress in the soil can also be explained by differences in bioavailability of the metal to the microorganisms. This, in turn, is influenced by soil characteristics such as CEC, pH, soil particles and other factors. Therefore, aside from selecting the appropriate techniques to better understand microbial responses to metals, it is also important to understand the prevalent environmental conditions that interplay to bring about observed changes in any given soil parameter.

전국 미곡종합처리장에서 채집한 2009년산 쌀과 가공부산물 시료의 독소생성곰팡이 오염 (Toxigenic Fungal Contaminants in the 2009-harvested Rice and Its Milling-by products Samples Collected from Rice Processing Complexes in Korea)

  • 손승완;남영주;이승호;이수민;이수형;김미자;이데레사;윤종철;류재기
    • 식물병연구
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    • 제17권3호
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    • pp.280-287
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    • 2011
  • 본 연구에서 우리나라 미곡종합처리장의 가공단계별 7종의 쌀 시료에 대한 곰팡이 오염 정도를 조사하였다. 곰팡이독소를 생산하는 곰팡이인 Aspergillus spp., Fusarium spp., Penicillium spp., Alternaria spp.가 우점하고 있었고, 포장곰팡이인 Fusarium과 Alternaria는 남부지방에 저장곰팡이인 Aspergillus와 Penicillium는 중부지방에 오염이 많았다. 또한 원료벼에서 가공단계가 진전될수록 Fusarium과 Alternaria와 같은 포장곰팡이의 오염 정도는 낮아졌으나 심하게 오염된 전라도 시료에서는 크게 낮아지지 않는 경향을 보였다. Aspergillus와 Penicillium과 같은 저장 곰팡이의 오염 정도는 가공단계가 진전될수록 높은 경향을 보였다. 또한 7종의 쌀 시료에는 총 35종의 곰팡이 속(genus)이 오염되어 있었으며 이 중 Myrothecium spp.는 우리나라 쌀 시료에서 처음으로 검출되었다. 이러한 결과는 우리나라의 주식인 쌀의 수확 후 저장, 가공과정의 곰팡이독소의 오염을 종합적으로 관리하기 위한 기초 자료가 될 것이다.

오염지하수출의 미생물학적 복원기술 (BIOLOGICAL REMEDIATION OF CONTAMINATED AQUIFER)

  • 배우근
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1992년도 폐기물 매립지의 공학적 특성과 개량기술
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    • pp.1-18
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    • 1992
  • The contaminatlon of soil and groundwater by leachate from impmperly managed landfills, or by cheiicals and gasoline leaked flu underground storage tanks has buou a serious urldwide environmental problei. Most of those contaminants are adsorptive and absorptive into soul, while they are hardly soluble in water. Thus, the rate of self purification is very slow, causing persistent problems in water use and environmental protection when the contamination is left untreated. Biological remediatlon technologies utilize the ertraordlnary caperbllity of microorganisms In degrading a tilde spectrum of organic compounds. Among them, an in situ bioremediation technology Involves injection of supplementary materials into the subsurfce in order to bring about a significant Increase in the microbial activity. The Increased microbial activity helps remove the pollutants in situ, that is, without digging out contaminants, soil, or water. This paper focused on the features, possibilities, and limitations of the bioremedition technology.

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Direct-Current Based Remedial Technologies for Contaminated Soils and Groundwaters

  • Lee, Suk-Young;Lee, Chae-Young;Yoon, Jun-Ki;Kim, Kil-Hong
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.3-6
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    • 2002
  • Electron transfer is the major natural process governing the behavior of contaminants in soils and groundwaters. Biological degradation of contaminants, i.e., microbial transformation of hazardous compounds, is a well known irreversible electron transfer process. Although it is not well defined as a separate process, abiotic electron-transfer is also an important process for mobilizing/demobilizing inorganic contaminants in soils and groundwaters. Therefore, numerous remedial technologies have been developed on the basis of electron transfer concept. Among them,

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