• 제목/요약/키워드: oxidative characteristics

검색결과 323건 처리시간 0.028초

여수 유류유출사고 방제작업자의 건강영향평가 (Health Effect Assessment on Cleanup Workers of an Oil Spill in Yeosu)

  • 김근배;강택신;윤미라;조혜정;주영경;유승도;이보은
    • 한국환경보건학회지
    • /
    • 제42권6호
    • /
    • pp.385-395
    • /
    • 2016
  • Objectives: The aim of this study was to assess exposure to VOCs and PAHs and the health effects on volunteers who participated in an oil spill cleanup in Yeosu. Methods: Atmospheric VOCs were evaluated in the vicinity of the accident site and questionnaire surveys were conducted to identify personal characteristics and acute health symptoms of clean-up workers seven days after the accident. The levels of metabolites of VOCs (t,t-MA, HA, PGA, MA, MHA) and PAHs (2-NAP, 1-OHP, 2-HF, 1-HPH), oxidative stress markers (TABARS, 8-OHdG) in the urine of workers were analyzed. Their correlation was determined by multiple regression analysis with SAS ver. 9.4. Results: Although the concentration of atmospheric VOCs in the residential areas were low at the time of survey, the levels of VOCs and PAHs metabolites in clean-up workers were higher than those in the control group after clean-up activities. The levels of urinary VOC and PAH metabolites were significantly increased after clean-up compared to those measured before participation. The thiobarbituric acid reactive substance (TBARS) concentrations were also increased and showed significant correlations with those of metabolites of benzene. Conclusion: This study shows that oil spill clean-up activities affect exposure to VOCs and PAHs and the health of clean-up workers. The results suggest the need for check-ups of participants in oil spill cleaning work.

건멸치의 크기가 저장성에 미치는 영향 (Effect of Sizes of Boiled-Dired Anchovies on the Storage Stability)

  • 조길석;김현구;김영명;강통삼
    • 한국식품과학회지
    • /
    • 제20권1호
    • /
    • pp.1-5
    • /
    • 1988
  • 건멸치 크기가 저장 안정성에 미치는 영향을 밝히기 위하여 KP/PE 포장한 건멸치를 $5^{\circ}C$에서 6개월간 저장하면서 주요 품질 지표성분의 변화를 조사하였다. 대멸의 TBA값, 지질산화에 의한 갈변 및 육 색깔의 변화는 중멸이나 소멸보다 켰다. 관능적인 기호도를 보통정도 수준인 3.0점을 기준으로 하여 저장기간을 설정하면 모두 6개월이상 저장 가능하였으나 소멸의 품질이 가장 우수하였고 다음이 중멸이었으며 대멸의 품질이 가장 나빴다. 대멸의 저장기간은 중멸이나 소멸의 약 절반에 상당하였다. 저장중 품질변화를 지질산화에 의한 갈변만 측정하여 관능검사와 같은 결과를 얻을 수 있는 회귀 방정식을 도출하였다.

  • PDF

베타 아밀로이드 유도성 Neuro 2A 세포독성에 대한 총명탕의 효과 (Chongmyung-tang Inhibits the Cytotoxicity of Beta-amyloid in Neuro 2A Neuroblastoma Cells)

  • 국윤재;최혁;김태헌;강형원;유영수
    • 동의생리병리학회지
    • /
    • 제18권5호
    • /
    • pp.1418-1425
    • /
    • 2004
  • The water extract of Chongmyung-tang has been traditionally used for treatment of memory-disorder in oriental medicine. This study was designed to investigate the protective mechanisms of Chongmyung-tang on β-amyloid or H₂O₂-induced cytotoxicity in Neuro 2A cells. The water extract of Chongmyung-tang significantly reduced both β-amyloid or H₂O₂-induced cell death and apoptotic characteristics through reduction of intracellular peroxide generation. Also, it inhibited the mitochondrial dysfunction including the disruption of mitochondria membrane permeability transition(MPT) and the modulation in expression of Bcl-2 family proteins in H₂O₂-treated H9c2 cells. Furthermore, pretreatment of quercetin inhibited the activation of caspase-3, in turn, degradation of ICAD/DFF45 were completely abolished in H₂O₂-treated cells. Taken together, that data suggest that the protective effects of the water extract of Chongmyung-tang against β-amyloid induced oxidative injuries may be achieved through modulation of mitochondrial dysfunction.

산화아연 나노구조의 탄소나노튜브와의 혼성구조 형성 특성 연구 (Parametric Characterization of Zinc Oxide Nanostructures Forming Three-Dimensional Hybrid Nanoarchitectures on Carbon Nanotube Constructs)

  • 옥종걸
    • 대한기계학회논문집B
    • /
    • 제39권6호
    • /
    • pp.541-548
    • /
    • 2015
  • 본 논문에서는 순차적 화학기상증착법에 기반하여 다양한 구조적 특성을 갖는 산화아연 나노구조체를 탄소나노튜브 상에 3 차원 혼성구조로 형성하는 공정을 개발하고 그 형성 메커니즘을 논한다. 이어서 나노와이어, 나노로드, 나노플레이트, 다결정 나노박막 등 다양한 형상의 산화아연 나노구조를 온도, 압력, 개스유량 등 주요 파라미터들의 조절을 통해 형성할 수 있음을 보이며, 이의 형성 원리에 대해 기본적인 형성 메커니즘과 연계하여 고찰한다. 본 연구 결과를 통해, 압전 및 광전 에너지변환 특성 등 풍부한 기능성을 보유하되 다소 높은 전기저항을 갖는 산화아연 나노구조체를 다양한 포맷으로 양전도성의 탄소나노튜브와 혼성화 함으로써, 각각의 포맷 별로 특화된 보다 폭넓은 응용 분야로의 활용을 구현해 나갈 수 있을 것이다.

Increasing the Triacylglycerol Content in Dunaliella tertiolecta through Isolation of Starch-Deficient Mutants

  • Sirikhachornkit, Anchalee;Vuttipongchaikij, Supachai;Suttangkakul, Anongpat;Yokthongwattana, Kittisak;Juntawong, Piyada;Pokethitiyook, Prayad;Kangvansaichol, Kunn;Meetam, Metha
    • Journal of Microbiology and Biotechnology
    • /
    • 제26권5호
    • /
    • pp.854-866
    • /
    • 2016
  • The production cost of biodiesel from microalgae is still not competitive, compared with that of petroleum fuels. The genetic improvement of microalgal strains to increase triacylglycerol (TAG) accumulation is one way to reduce production costs. One of the most promising approaches is the isolation of starch-deficient mutants, which have been reported to successfully increase TAG yields. To date, such a stable mutant is not available in an oleaginous marine microalga, despite several advantages of using marine species for biodiesel production. Algae in the genus Dunaliella are known to tolerate high salt concentration and other environmental stresses. In addition, the cultivation processes for large-scale outdoor commercialization have been well established for this genus. In this study, Dunaliella tertiolecta was used to screen for starch-deficient mutants, using an iodine vapor-staining method. Four out of 20,016 UV-mutagenized strains showed a substantial reduction of starch content. A significantly higher TAG content, up to 3-fold of the wild-type level, was observed in three of the mutants upon induction by nitrogen depletion. The carotenoid production and growth characteristics of these mutants, under both normal and oxidative stress conditions, were not compromised, suggesting that these processes are not necessarily affected by starch deficiency. The results from this work open up new possibilities for exploring Dunaliella for biodiesel production.

Multiple Tolerances and Dye Decolorization Ability of a Novel Laccase Identified from Staphylococcus Haemolyticus

  • Li, Xingxing;Liu, Dongliang;Wu, Zhaowei;Li, Dan;Cai, Yifei;Lu, Yao;Zhao, Xin;Xue, Huping
    • Journal of Microbiology and Biotechnology
    • /
    • 제30권4호
    • /
    • pp.615-621
    • /
    • 2020
  • Laccases are multicopper oxidases with important industrial value. In the study, a novel laccase gene (mco) in a Staphylococcus haemolyticus isolate is identified and heterologously expressed in Escherichia coli. Mco shares less than 40% of amino acid sequence identities with the other characterized laccases, exhibiting the maximal activity at pH 4.0 and 60℃ with 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) as a substrate. Additionally, the Mco is tolerant to a wide range of pH, heavy metal ions and many organic solvents, and it has a high decolorization capability toward textile dyes in the absence of redox mediators. The characteristics of the Mco make this laccase potentially useful for industrial applications such as textile finishing. Based on BLASTN results, mco is found to be widely distributed in both the bacterial genome and bacterial plasmids. Its potential role in oxidative defense ability of staphylococci may contribute to the bacterial colonization and survival.

정수처리에서의 생물활성탄 공정 (Biological Activated Carbon (BAC) Process in Water Treatment)

  • 손희종;유수전;노재순;유평종
    • 대한환경공학회지
    • /
    • 제31권4호
    • /
    • pp.308-323
    • /
    • 2009
  • 생물활성탄 공정은 정수처리에서 획기적인 공정으로 평가받고 있으며, 전 세계적으로 많은 정수장에서 BAC 공정을 채택하여 운전하고 있다. BAC 공정의 장점은 활성탄에 흡착된 오염물질들이 활성탄 표면에서 서식하고 있는 다양한 미생물 집합체(생물막)에 의해 생물분해되어 자연적으로 활성탄의 재생이 이루어져 활성탄 사용기간의 연장을 유도하여 정수처리 비용을 감소시킬 수 있다는 것이다. 또한, 유입수중의 생분해 가능한 유기물질들을 제거하여 배 급수관망에서 미생물의 재성장을 억제하는데 탁월하다. 그러나 BAC 공정의 효율이 활성탄 표면에 형성되어 있는 생물막에 의해 제한되어지는 문제점도 있다. 본 논문에서는 GAC에서 BAC로의 전환, BAC 생물막의 특성, 오염물질의 제거 메카니즘, BAC 공정에 영향을 미치는 인자들, BAC 공정의 제어 및 BAC 공정의 모델링에 대해 크게 여섯 부분으로 상세하게 기술하였다.

Plant Extracts and Plant-Derived Compounds: Promising Players in Countermeasure Strategy Against Radiological Exposure: A Review

  • Kma, Lakhan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권6호
    • /
    • pp.2405-2425
    • /
    • 2014
  • Radiation exposure leads to several pathophysiological conditions, including oxidative damage, inflammation and fibrosis, thereby affecting the survival of organisms. This review explores the radiation countermeasure properties of fourteen (14) plant extracts or plant-derived compounds against these cellular manifestations. It was aimed at evaluating the possible role of plants or its constituents in radiation countermeasure strategy. All the 14 plant extracts or compounds derived from it and considered in this review have shown some radioprotection in different in vivo, ex-vivo and or in vitro models of radiological injury. However, few have demonstrated advantages over the others. C. majus possessing antioxidant, anti-inflammatory and immunomodulatory effects appears to be promising in radioprotection. Its crude extracts as well as various alkaloids and flavonoids derived from it, have shown to enhance survival rate in irradiated mice. Similarly, curcumin with its antioxidant and the ability to ameliorate late effect of radiation exposure, combined with improvement in survival in experimental animal following irradiation, makes it another probable candidate against radiological injury. Furthermore, the extracts of P. hexandrum and P. kurroa in combine treatment regime, M. piperita, E. officinalis, A. sinensis, nutmeg, genistein and ginsan warrants further studies on their radioprotective potentials. However, one that has received a lot of attention is the dietary flaxseed. The scavenging ability against radiation-induced free radicals, prevention of radiation-induced lipid peroxidation, reduction in radiation cachexia, level of inflammatory cytokines and fibrosis, are some of the remarkable characteristics of flaxseed in animal models of radiation injury. While countering the harmful effects of radiation exposure, it has shown its ability to enhance survival rate in experimental animals. Further, flaxseed has been tested and found to be equally effective when administered before or after irradiation, and against low doses (${\leq}5Gy$) to the whole body or high doses (12-13.5 Gy) to the whole thorax. This is particularly relevant since apart from the possibility of using it in pre-conditioning regime in radiotherapy, it could also be used during nuclear plant leakage/accidents and radiological terrorism, which are not pre-determined scenarios. However, considering the infancy of the field of plant-based radioprotectors, all the above-mentioned plant extracts/plant-derived compounds deserves further stringent study in different models of radiation injury.

Study on the promotion of inflammation and whitening of natural materials using bioconversion technology

  • Lee, Se-Won;Lim, Jeong-Muk;Lee, Seong-Hyeon;Lee, Jeong-Ho;Oh, Byung-Teak
    • 한국자원식물학회:학술대회논문집
    • /
    • 한국자원식물학회 2018년도 추계학술대회
    • /
    • pp.116-116
    • /
    • 2018
  • Bioconversion, the enzymatic process by microorganism on organic precursor to desired products. The natural extract is converted into a form that can be easily absorbed into the skin, while scaling up of to higher quantity is possible. Selection of naturally processed raw material rather than chemically processed is preferred. Therefore, fermentation was carried out by mixing Rubus coreanus Miquel, soybean, Zanthoxylum schinifolium as bioconverting materials, the possibility of inflammation, whitening material were checked. In this study, useful microorganisms were isolated from various salted fish, and 16S rDNA sequence was analyzed to confirm their genetic characteristics. Combining the three natural materials using bioconversion technology to study their activity before and after fermentation. To evaluate the antioxidant activity and the active ingredient content the DPPH radical scavenging activity and the total polyphenol content were examined. Raw 264.7 cells were used to evaluate MTT assay, NO and $TNF-{\alpha}$ production inhibitory activity. Also, to evaluate the whitening activity, tyrosinase inhibitory activity and melanin formation inhibitory activity were measured using B16F10 cells. In total 34 strains were obtained from various salted fish. The effective strains useful for the bioconversion process, showed that DPPH radical scavenging ability and polyphenol content were increased in the two kinds of microbial treatment groups compared to the untreated group. 16S rDNA sequencing analysis of the strains showed excellent in Pediococcus pentosaceus B1 in comparison. An increase of up-to 156% in anti-oxidative activity and 141% in polyphenol content was observed after bioconversion. In addition, after mixed fermentation the toxidty of Raw 264.7 and B16F10 cells tended to decrease and a significant increase was observed in anti-inflammatory activity as well. Also, tyrosinase activity and melanin significantly. synthesis decreased significantly.

  • PDF

CVD로 제작된 SiO2 산화막의 투습특성 (Water Vapor Permeability of SiO2 Oxidative Thin Film by CVD)

  • 이붕주;신현용
    • 한국전자통신학회논문지
    • /
    • 제5권1호
    • /
    • pp.81-87
    • /
    • 2010
  • 본 논문에서는 유기발광다이오드 적용을 위한 보호막 혹은 barrier 적용을 위하여 화학증착방법(CVD)를 이용한 실리콘 산화막을 형성하고, 산화막의 특성에 영향을 미치는 공정조건을 변화시켰다. 이로부터 HDP-CVD를 활용한 $SiO_2$박막 증착을 위한 최적의 공정조건은 $SiH_4:O_2$=30:60[sccm]유량, 소스와 기판과의 거리가 70 [mm], 기판에 Bias를 가하지 않은 조건인 경우 8~10[mtorr] 공정압력에서 매우 안정된 플라즈마 형성이 가능한 최적의 공정조건을 얻었다. 얻어진 공정조건으로 제작된 $SiO_2$산화막의 모콘테스트를 통한 투습율(WVTR)을 조사한 결과 2.2 [$g/m^2$_day]값으로 HDP-CVD로 제작된 $SiO_2$산화막은 유기발광다이오드용 보호막으로의 적용이 어려울 것으로 생각된다.