• 미생물학회지
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• 제36권4호
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• pp.285-291
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• 2000

강진만 수역에서 이화학적 요인과 미생물군집의 변화를 조사하기 위해 영양염류, 수온, 투명도, 염분도, DO, COD 및 종속영양세균, 균류 그리고 분변성 대장균을 계절별로 분석하였다. 분석 결과 조사기간 동안 분변성 대장균군과 종속영양세균의 개체수 변화는 각각 16.1~166.0 CFU/ml 과 $5.0{\times}10^3$~$13.1{\times}10^3$CFU/ml의 범위를 보였다. 또한 이들 세균군집의 정점별 평균값은 다른 정점보다 담수유입 수역인 1번 정점에서 매우 높은 밀도를 보였다. 이화학적 조사와 미생물학적 조사 결과를 고찰했을 때 강진만 생태계는 계절에 따라 2~4개 요인에 의하여 조절되는 것으로 보이며, 주로 담수유입, 영양염류, 염분도 그리고 수온 등에 의하여 영향을 받는 것으로 판단되었다. 이들 결과로 볼 때 강진만의 생태계에서 환경 요인의 영향은 다른 만 (광양만, 진해만, 마산만 등)에 비해 상대적으로 적었던 것으로 사료된다.

• 한국환경농학회지
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• 제40권4호
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• pp.295-312
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• 2021

BACKGROUND: Global warming is one of the most pressing environmental issues which concomitantly complicates global climate change. Methane emission is a balance between methanogenesis and methane consumption, both of which are driven by microbial actions in different ecosystems producing methane, one of the major greenhouse gases. Paddy fields are major sources of anthropogenic methane emissions and could be compounded by organic fertilization. METHODS AND RESULTS: Literature reviews were conducted to give an overview of the global warming conditions and to present the relationship of carbon and methane to greenhouse gas emissions, and the need to understand the underlying processes of methane emission. A more extensive review was done from studies on methane emission in paddy fields under organic fertilization with greater emphasis on long term amendments. Changes in paddy soils due to organic fertilization include alterations of the physicochemical properties and changes in biological components. There are diverse phylogenetic groups of methanogens and methane oxidizing bacteria involved in methane emission. Also, multiple factors influence methanogenesis and methane oxidation in rice paddy fields under organic fertilization and they should be greatly considered when developing mitigating steps in methane emission in paddy fields especially under long term organic fertilization. CONCLUSION(S): This review showed that organic fertilization, particularly for long term management practices, influenced both physicochemical and biological components of the paddy fields which could ultimately affect methanogenesis, methane oxidation, and methane emission. Understanding interrelated factors affecting methane emission helps create ways to mitigate their impact on global warming and climate change.

• 한국미생물·생명공학회지
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• 제35권4호
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• pp.261-271
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• 2007

토양오염을 복원하는 방법 중 식물상 복원은 식물을 이용하여 오염물을 제거하는 기술로, 환경 친화적이며, 경제적인 기술이기 때문에 많이 이용되고 있다. 이 연구에서는 식물상 복원에 있어 식물의 영향, 근권 세균과 물리화학적 제한인자에 대해 고찰하였다. 성공적인 식물상 복원을 위해서는 식물의 선택이 가장 중요하다. 유류(디젤) 분해를 위해 적용된 식물은 쥐보리(Lolium multiflorum lam), 베치(Vicia villosa), 버섯류(white mustard), 톨페스큐(Festuca arundinacea), 콩과식물(leguminosae), 포플러, 소나무(Pinus densiflora) 등이고, 유류 제거 효율은 68-99% 이었다. PAH(polycyclic aromatic hydrocarbons) 제거용으로는 옥수수(Zeo mays), 쥐보리, 베치, 버섯류, 토끼풀(Trifolium repens), 그리고 톨페스큐이 이용되었고, 50-98%의 제거 효율을 보였다. 식물의 성장을 향상시킬 뿐 만 아니라, 오염물질을 직접적으로 제거할 수 있는 근권 세균도 식물상 복원에 있어 중요한 역할을 한다. 식물상 복원에 이용된 근권 세균에는 Azospirillum lipoferum, Enterobactor cloacae, Azospirillum brasilense, Pseudomonas putida, Burkholderia xenovorans, Comamonas testosterone, Pseudomonas gladioli, Azotobacter chroococcu, Bacillus megaterium, Bacillus subtilis 등이 있다. pH, 온도, 영양물질, 최종전자수용체, 수분함량, 유기물 함량, 오염물질 종류와 물리화학적 인자도 식물상 복원에 있어 제한 요소로 작용한다.

• 미생물학회지
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• 제28권4호
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• pp.324-330
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• 1990

The distribution of physicochemical environmental factors and microbiological factors was studied at 6 sampling sites in Kyeongge Bay of Yellow Sea from October 1989 to October 1990. The total bacterial number, saprophytic bacterial number, petroleum-degrading bacterial number, bacterial biomass, and bacterial secondary production were measured in the range of 0.09~1.24*10$^{7}$ cells/ml, 7~60000 CFUs/ml, 0~240 cells/ml, 14.16~301 .$\mu$g-C/l, and 0.13~11.82 mg-C/m$^{3}$/hr, respectively. The turnover times of $^{3}$H-glucose and $^{3}$H-acetate were in range of 6.5~6984 and 41~24897 hours, respectively. The spatial distribution of heterotrophic bacterial communities were hightly affected by influx of organic pollutants from the coastal area and the seawater exchange with offshore.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.2019-2027
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• 2017

Recently, cabbage kimchi has occasionally been associated with the foodborne diseases of enteric viruses such as human norovirus (HuNoV). This study aimed to evaluate the correlation between microbial/physicochemical properties and persistence of HuNoV in experimentally contaminated cabbage kimchi fermented and stored at $4^{\circ}C$ or $10^{\circ}C$ for 28 days. Changes in organic acid content, lactic acid bacteria (LAB), acidity, pH, and salinity were analyzed. The recovery of structurally intact HuNoV was examined for up to 28 days post-inoculation, using a NoV GII.4 monoclonal antibody-conjugated immuno-magnetic separation method combined with quantitative real-time reverse transcription polymerase chain reaction. On day 0, LAB loads were $4.70log_{10}$ colony forming units/g and HuNoV GII.4 titers were $2.57log_{10}\;genomic\;copies/{\mu}l$, at both temperatures. After 28 days, intact HuNoV titers decreased to 1.58 ($4^{\circ}C$) and $1.04(10^{\circ}C)log_{10}\;genomic\;copies/{\mu}l$, whereas the LAB density increased. This correlated with a gradual increase in lactic acid and acetic acid at both temperatures. Our findings support a statistical correlation between changes in physicochemical properties and the recovery of structurally intact HuNoV GII.4. Moreover, we determined that the production of organic acid and low pH could affect HuNoV GII.4 titers in cabbage kimchi during fermentation. However, HuNoV GII.4 was not completely eliminated by microbial/physicochemical factors during fermentation, although HuNoV GII.4 was reduced. Based on this, we speculate that the persistence of HuNoV GII.4 may be affected by the continually changing conditions during kimchi fermentation.

• 한국식품과학회지
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• 제26권3호
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• pp.300-304
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• 1994

고추장의 유통기간 중 품질변화를 예측하기 위하여 숙성 완료된 고추장을 $13^{\circ}C$, $27^{\circ}C$ and $37^{\circ}C$ 에 저장하면서 품질의 변화를 측정하였다. 수분, 조단백질, 캡사이신함량은 저장 중 거의 변화하지 않았으나, 아미노태질소, 표면색도, pH는 감소하는 경향을 나타내었으며 암모니아태질소, 산도는 증가하였다. 이러한 증감현상은 저장온도가 높을수록 더욱 뚜렷하여 저장 온도가 고추장의 품질변화에 밀접한 관련이 있음을 알 수 있었다. 총균수는 저장온도 및 기간의 증가에 따라 큰 변화는 보이지 않았으며, 진균류는 검출되지 않았다. 이화학적 품질 특성과 관능검사와의 상관관계를 구한 결과 아미노태질소의 변화가 가장 높은 상관관계를 보였다. 저장기간에 따른 아미노태 질소값의 변화율은 1차 반응식으로 해석되었음, 반응상수로부터 계산된 $Q_{10}$값은 2.98이었다. 또한, Arrhenius equation을 이용하여 활성화에너지를 구한 결과 15.84 Kcal/mole인 것으로 나타났다.

• 생태와환경
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• 제55권2호
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• pp.156-166
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• 2022

호소의 수질 특성을 이해하는 것은 호소 및 정수생태계 관리의 가장 기본 요소이다. 호소의 수질은 호소의 수리수문학적 요소, 주변 토지 이용/피복, 유역 내 인간 활동을 포함한 다양한 요인에 의해 영향을 받는다. 본 연구에서는 호소에서 5년 동안(2015~2019) 측정된 9가지 이화학적 요인(pH, DO, COD, TSS, T-N, T-P, TOC, EC, Chl-a)을 이용하여, 국내 83개 주요 호소를 수질에 따라 분류하였다. 계층적 그룹 분석을 통해 전체 호소는 총 5개의 유형으로 분류되었고, 각 유형별로 저수지의 수질 및 고도, 유역면적, 만수위, 총 저수량과 같은 수리수문학적 요인을 반영하였다. 특히 저고도에 위치한 대형 호소에서(그룹 I) 수질이 매우 낮게 나타났다. 한국형 부영양화 지수를 이용하여 국내 주요 호소의 부영양화 정도를 비교한 결과, 석호가 포함된 그룹 IV 및 신갈지 등에서는 과거 2004~2008년에 비해 부영양화 지수가 개선되었으나, 그룹 I, III, V에 속한 대부분의 농업용 저수지에서는 부영양화가 심화되었다.

• 상하수도학회지
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• 제11권1호
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• pp.81-87
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• 1997

Coagulation is very important process in water works. The subsequent processes are directly affected by this process. Many factors such as turbidity, alkalinity, pH, hardness, total organic carbon(TOC), velocity gradient and flocculation time effect on coagulation process. Among these factors, specially TOC is being concerned target substance to be removed due to trihalomenthanes(THMs) precursor and alkalinity is being one of the major parameter for removing TOC. We have researched the consumption of coagulant with TOC alkalinity concentration of water and removal efficiency of residual TOC and turbidity with alkalinity. Furthermore we have investigated particle size distributions with velocity gradient and alkalinity. The consumption of coagulant was proportionally increased to TOC and alkalinity concentration and the removal of TOC in Nakdong river water was very difficult more than 150 mg/l in alkalinity but large morecular weight organic such as humic acid could be removed easily. Coagulation of low alkalinity water was more rapidly occured than of high alkalinity water by analyzing the particle size distributions. High alkalinity water needed higher mixing energy for a good coagulation within limited flocculation time.

• Genomics & Informatics
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• 제21권2호
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• pp.21.1-21.14
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• 2023

Fusobacterium nucleatum is a gram-negative bacteria associated with diverse infections like appendicitis and colorectal cancer. It mainly attacks the epithelial cells in the oral cavity and throat of the infected individual. It has a single circular genome of 2.7 Mb. Many proteins in F. nucleatum genome are listed as "Uncharacterized." Annotation of these proteins is crucial for obtaining new facts about the pathogen and deciphering the gene regulation, functions, and pathways along with discovery of novel target proteins. In the light of new genomic information, an armoury of bioinformatic tools were used for predicting the physicochemical parameters, domain and motif search, pattern search, and localization of the uncharacterized proteins. The programs such as receiver operating characteristics determine the efficacy of the databases that have been employed for prediction of different parameters at 83.6%. Functions were successfully assigned to 46 uncharacterized proteins which included enzymes, transporter proteins, membrane proteins, binding proteins, etc. Apart from the function prediction, the proteins were also subjected to string analysis to reveal the interacting partners. The annotated proteins were also put through homology-based structure prediction and modeling using Swiss PDB and Phyre2 servers. Two probable virulent factors were also identified which could be investigated further for potential drug-related studies. The assigning of functions to uncharacterized proteins has shown that some of these proteins are important for cell survival inside the host and can act as effective drug targets.

• Safety and Health at Work
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• 제14권1호
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• pp.17-30
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• 2023

The human reproductive system can be affected by occupational exposure to many physical and chemical risk factors. This study was carried out to review the studies conducted on the issue of the pathophysiological effects of occupational physical and chemical risk factors on the reproductive system of females and males. In this systematic review, the databases such as "Google Scholar," "Pub-Med," "Scopus," and "Web of Science" were used. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA 2020), the studies included in our study were published between 2000 and 2021. In order to extract the required data, all sections of the articles were reviewed. Out of 57 articles we reviewed, 34 articles were related to field studies and 23 articles to clinical studies. Among them, 43 studies dealt with the pathophysiological effects of chemical agents, six studies dealt with the pathophysiological effects of physical factors, and 8 studies dealt with the pathophysiological effects of physicochemical factors on the human reproductive system. Physical (noise, heat, and radiofrequency radiation) and chemical (such as carbamate and organophosphate pesticides, benzene, toluene, xylene, formaldehyde, NO2, CS2, manganese, lead, nickel, and n-hexane) risk factors had pathophysiological effects on the human reproductive system. The presence of these risk factors in the workplace caused damage to the human reproductive system. The rate of these negative pathophysiological effects can be reduced by performing appropriate managerial, technical, and engineering measures in work environments.