• 제목/요약/키워드: Degradation agent

검색결과 344건 처리시간 0.02초

Development of Anti-Melanogenic Agent for Skin Whitening

  • Ahn, Soo-Mi
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2007년도 Proceedings of The Convention
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    • pp.129-139
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    • 2007
  • Many modalities of treatment for acquired skin hyperpigmentation are available including chemical agents or physical therapies, but none are completely satisfactory. The ideal depigmenting compound should have a potent. rapid and selective bleaching effect on hyperactivated melanocytes, carry no short- or long-term side-effects and lead to a permanent removal of undesired pigment. acting at one or more steps of the pigmentation process. Depigmentation can be achieved by regulating (i) the transcription and activity of tyrosinase, tyrosinase related protein-1 (TRP-1), tyrosinase related protein-2 (TRP-2), and/or peroxidase; (ii) the uptake and distribution of melanosomes in recipient keratinocytes and (iii) melanin and melanosome degradation and turnover of pigmented keratinocytes. One of the interesting point for development of skin whitening agent is Mitf(Microphthalmia-associated transcription factor). Mitf belongs to the basic helix-loop-helix-zip family of trabscription factors and it is crucial as it regulates both melanocyte proliferation as well as melanogenesis and is the major regulator of tyrosinase and the related enzymes (TRPs), as well as many melanosome structural proteins such as pMel17. Recently, we developed MITF-down-regulating agents from natural and synthetic sources, which have anti-melanogenic effect on in vitro and in vivo. We suggested that potent MITF-down regulating agents might be used for skin whitening cosmeceuticals.

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전해 산화제에 의한 악취 원인 VOCs 제거 특성 (Characteristics of odorous VOCs removal by using electrolytic oxidant)

  • 이태호;류희욱
    • 실내환경 및 냄새 학회지
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    • 제17권4호
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    • pp.381-388
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    • 2018
  • In this study, various conditions and phenomena that occur in the process of removing odorous VOCs by using electrolyzed oxidant were examined. The formation of hypochlorous acid, which is an oxidant produced by electrolysis, was investigated and the properties of the oxidizing agent used to decompose toluene, xylene, and cyclohexane were investigated. As a result, it was found that the production rate and the final concentration of the oxidizing agent increased with the current density. It was found that the degree of removal varies depending on the property of each pollutant. Interestingly, in the batch experiments in which the pH of the produced oxidant was controlled, it was found that the degree of elimination varied depending on the pH of the substance. These results suggest that the difference in the concentration and distribution of hypochlorous acid (HOCl) and hypochlorite ($OCl^-$) due to the pH change leads to the difference in oxidizing power on the oxidation characteristics of each substance. Styrene and terpineol showed better degradation characteristics than toluene and xylene in odorous VOC removal experiments by spraying electrolytic oxidant using a lab-scale continuous reactor. In conclusion, the removal of odorous VOCs by the electrolytic oxidant can have various applications in that it can oxidize pollutants of various spectra.

미생물제(Rhodococcus sp. 3-2) 처리에 따른 토양 중 카벤다짐의 분해효과 (Degradation effect of carbendazim in soil by application with the microbial agent, Rhodococcus sp. 3-2)

  • 연제형;김현수;안재형;한귀환;오영곤;조일규;박인철
    • 한국환경농학회지
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    • 제40권4호
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    • pp.322-329
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    • 2021
  • BACKGROUND: The fungicide of benomyl, a benzimidazole group, has been commonly used for pesticides against fungal diseases in the world. However, benomyl is rapidly hydrolyzed in the environment after using to control plant diseases and has adverse effects by generating carbendazim, which is toxic to plants, humans, and the environment. METHODS AND RESULTS: In this study, the decomposition effect of carbendazim, a degradation product of benomyl was conducted in pot and field after making a prototype of benomyl-degrading microbial agent (BDMA). We found that the carbendazim-degrading microbial agent (CDMA) (105, 106, and 107 cfu/g soil) decomposed carbendazim by 50% or more in all the treatments, compared to the untreated control in the pot tests after four weeks. The effect of 100% decomposition of carbendazim was observed at 7 days after treatment, when the prototype of BDMA was apllied at 10-folds dilution in the field. The decomposition effect at more than 60% and plant growth promoting effect were observed after 7 days of the treatment, compared with the untreated group in the second field experiment,treated with commercially available concentrations of 500-folds and 1,000-folds. CONCLUSION(S): These results might represent that the BDMA would decompose carbendazim effectively, a decomposition product of the fungicide benomyl, remaining in agricultural area, and it could be utilized practically by using a low dilution rate.

Antimicrobial Peptide, Lumbricusin, Ameliorates Motor Dysfunction and Dopaminergic Neurodegeneration in a Mouse Model of Parkinson's Disease

  • Kim, Dae Hong;Lee, Ik Hwan;Nam, Seung Taek;Hong, Ji;Zhang, Peng;Lu, Li Fang;Hwang, Jae Sam;Park, Ki Cheol;Kim, Ho
    • Journal of Microbiology and Biotechnology
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    • 제25권10호
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    • pp.1640-1647
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    • 2015
  • We recently reported that the antimicrobial peptide Lumbricusin (NH2-RNRRWCIDQQA), isolated from the earthworm, increases cell proliferation in neuroblastoma SH-SY5Y cells. Here, we investigated whether Lumbricusin has neurotropic activity in mouse neural stem cells (MNSCs) and a protective effect in a mouse model of Parkinson's disease (PD). In MNSCs isolated from mouse brains, Lumbricusin treatment significantly increased cell proliferation (up to 12%) and reduced the protein expression of p27Kip1 through proteasomal protein degradation but not transcriptional regulation. Lumbricusin inhibited the 6-OHDA-induced apoptosis of MNSCs, and also showed neuroprotective effects in a mouse PD model, ameliorating the motor impairments seen in the pole, elevated body swing, and rotation tests. These results suggest that the Lumbricusin-induced promotion of neural cell proliferation via p27Kip1 degradation has a protective effect in an experimental PD model. Thus, the antimicrobial peptide Lumbricusin could possibly be developed as a potential therapeutic agent for the treatment of PD.

영가철 기반 펜톤 시스템을 활용한 페놀의 산화분해 (Oxidative Degradation of Phenol Using Zero-Valent Iron-Based Fenton-Like Systems)

  • 김학현;이혜진;김형은;이홍신;이병대;이창하
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제18권4호
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    • pp.50-57
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    • 2013
  • For the last couple of decades, the Fenton (-like) systems have been extensively studied for oxidation of organic contaminants in water. Recently, zero-valent iron (ZVI) has received attention as a Fenton catalyst as well as a reducing agent capable of producing reactive oxidants from oxygen. In this study, the ZVI-based Fenton reaction was assessed for the oxidative degradation of phenol using $ZVI/O_2$, $ZVI/H_2O_2$, ZVI/Oxalate/$O_2$ and hv/ZVI/Oxalate/$O_2$ systems. Reaction parameters such as pH and reagent dose (e.g., ZVI, $H_2O_2$, and oxalate) were examined. In the presence of oxalate (ZVI/Oxalate/$O_2$ and hv/ZVI/Oxalate/$O_2$ systems), the degradation of phenol was greatly enhanced at neutral pH values. It was found that ZVI accelerates the Fenton reaction by reducing Fe(III) into Fe(II). The conversion of Fe(III) into Fe(II) by ZVI was more stimulated at acidic pH than at near-neutral pH values.

배양된 기도 상피세포에서 종양괴사인자에 의한 $I{\kappa}B$의 분해와 NF-${\kappa}B$ p65의 핵으로의 이동에 미치는 실리비닌과 레스베라트롤의 영향 (Effects of Silibinin and Resveratrol on Degradation of $I{\kappa}B$ and Translocation of NF-${\kappa}B$ p65 Induced by Tumor Necrosis Factor-${\alpha}$ in Cultured Airway Epithelial Cells)

  • 박수현;이현재;류지호;이수열;신현대;홍장희;석정호;이충재
    • 약학회지
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    • 제58권1호
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    • pp.1-6
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    • 2014
  • We examined whether silibinin and resveratrol affect airway mucin production, degradation of $I{\kappa}B$ and translocation of NF-${\kappa}B$ p65 induced by TNF-${\alpha}$ in NCI-H292 cells. Cells were pretreated with each agent for 30 min and then stimulated with TNF-${\alpha}$ for 24 h or the indicated periods. The two compounds suppressed TNF-${\alpha}$-induced airway mucin production, degradation of $I{\kappa}B$ and translocation of NF-${\kappa}B$ p65. This result suggests that silibinin and resveratrol can regulate the production of mucin induced by TNF-${\alpha}$ through the inactivation of NF-${\kappa}B$ pathway in airway epithelial cells.

젖산이 결합된 히아루론산 막의 특성 (Characterization of Hyaluronic Acid Membrane Containing Lactic Acid)

  • 정성일;권지영
    • 멤브레인
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    • 제15권1호
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    • pp.8-14
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    • 2005
  • 생체 적합성이 우수한 히아루론산과 생분해성이 우수한 폴리 락타이드의 모노머를 결합하여 인체내에서 분해속도를 조절할 수 있는 생체적합성이 우수한 생체 재료를 제조하고자 하였다. 냉동 건조법을 이용하여 히아루론산과 폴리락타이드의 모노머인 젖산 또는 이량체인 락타이드를 가교제 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide로 가교시켰다. 생성된 막을 적외선 흡수 분광법으로 분석한 결과 에스테르 결합이 생성됨을 확인하였고, 핵자기 공명 분광법으로 분석하여 이 에스테르 결합이 젖산의 반응 참여에 의한 것임을 확인하였다. 젖산과 히아루론산의 몰비를 1부터 10까지 증가시키면서 가교시킨 결과 젖산의 전화율(6∼32%)과 가교도(4∼l9%)는 증가하였으나, 반응에 참여한 젖산이 가교되는 선택도는 몰비에 관계없이 62% 정도로 일정하였다. 몰비가 커서 젖산이 많이 첨가되면 취성은 강해졌으나 생분해 속도는 빨라졌으며, 팽윤도는 500에서 2000% 범위의 값을 보였다.

Modified Photo-Fenton Reaction을 이용한 Methyl Tert-butyl Ether (MTBE)의 분해 Kinetic 및 메커니즘 규명에 관한 연구 (Degradation Kinetic and Mechanism of Methyl Tert-butyl Ether (MTBE) by the Modified Photo-Fenton Reaction)

  • 김민경;공성호
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제11권6호
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    • pp.69-75
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    • 2006
  • 지하 저장 탱크로부터의 유류 유출로 인하여 전세계적으로 넓은 지역의 토양 및 지하수가 오염되고 있다. Methyl tert-butyl ether(MTBE)는 대기 오염 감소를 위하여 널리 사용되고 있는 유류 첨가제이지만 토양 및 지하수로 유입되어 섭취 되었을 때 발암 가능성이 있는 유독 물질이다. 본 연구는 고도 산화 처리 기법 중 유기 오염물의 분해에 높은 효율을 나타내는 고전적 Fenton reaction의 최대 단점인 강한 산성(pH 2.5-3) 의존성을 극복한 새로운 산화 처리 기법을 개발하여 고농도의 MTBE를 효과적으로 분해 하는 것을 그 목적으로 하여 자연 친화적인 chelating agents를 사용하여 중성 영역에서 Fenton reaction을 가능하게 하는 기법인 Modified Fenton reaction과 Ultra Violet light(UV)를 이용하여 분해효율을 극대화 하는 Photo-assisted Fenton reaction을 응용한 Modified Photo-Fenton reaction system을 개발하여 최적 반응 조건 및 반응 차수, 반응 메커니즘을 밝혀내었다. 낮은 독성과 높은 생분해성을 나타낸 Citrate ion을 chelating agents로 선정하였으며 최적 반응 조건은 [$Fe^{3+}$] : [Citrate] = 1 mM : 4 mM, 3% $H_2O_2$, 17.4 kWh/L UV dose, 초기 pH 6.0이며 이 조건에서 1000 ppm MTBE를 분해한 결과 6시간 후 86.75%, 16시간 후 99.99%의 높은 분해율을 나타냈으며 최종 pH는 6.02로 안정적이었다. 또한 Modified Photo-Fenton reaction을 이용한 MTBE 분해 반응은 유사 1차 반응을 나타내었으며 methoxy group이 ${\cdot}OH$ radical과 주로 반응하여 tert-butyl formate(TBF)가 주요 분해 산물이 되는 분해 경로를 따른 다는 것이 밝혀졌다. 본 연구로 개발된 Modified Photo-Fenton reaction에서 발생되는 산화제인 ${\cdot}OH$ radical의 비선택적 반응성을 고려할 때 본 system은 다른 종류의 유기 오염물 분해에도 효과적일 것으로 판단된다.

스마트 데이터베이스 설계를 위한 연관성 기반 개념적 모형화 (Association-Based Conceptual Modeling for Smart Database Design)

  • 이상원
    • 지능정보연구
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    • 제17권3호
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    • pp.169-185
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    • 2011
  • 데이터 중복은 과중한 저장관리비용을 유발할 뿐만 아니라, 정보시스템의 질적 저하를 초래한다. 불행히도, 업무 규정에 적합하지 않은 데이터를 방지하기 위해서, 업무에 충실한 개념적 설계를 위한 시간과 노력을 투자하는 기업이 극소수에 불과하다. 즉, 대부분의 기업들은 데이터 품질에 대한 인식에 관심을 갖지 않는다. 우리 연구의 주요 동기는, 업무에 대한 사전지식이 없이 업무에 충실한 기업전사 데이터를 설계하는 방식을 연구하는 것이다. 본 논문에서는 업무기술서에 나온 각 문장 내의 객체들 간의 연관성을 이용해서, 데이터설계를 자동화하는 데이터설계방법론을 제안한다. 자동화 설계도구를 위해 제안된 에이전트는 자연어 상태의 업무설계서만을 입력 받아, 특정한 규칙을 이용하여 개체관계도를 설계한다. 우리는 본 에이전트의 전체 범위와 자세한 절차를 약간의 예를 가지고 설명을 할 것이고, 그 다음에 객체 간에 추출된 연관성의 적법성을 검증할 것이다. 또한, 고안된 에이전트의 실무 적용성을 평가하기 위한 사례연구를 진행할 것이다.

계면활성제가 첨가된 염수용액에 따른 폴리머 애자의 트래킹 성능 평가 (Tracking Performance Test of Polymer Insulator with Salt Solution which is added Surface Active Agent)

  • 조한구;이운용;한동희;강성화;최인혁;임기조
    • 한국전기전자재료학회논문지
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    • 제18권1호
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    • pp.62-67
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    • 2005
  • Recently, polymer insulators that are used for high voltage applications have some advantages such as light weight, small size, vandalism resistance, hydrophobicity and easy making process. During outdoor service of polymer insulators, the surface of the insulating material is frequently subjected to moisture and contamination that lead to dry band arcing. Their tracking resistance, erosion resistance, end sealing and shed design are very important because dry band arcing causes degradation of polymer surface. Aging test to estimate life property of polymer insulator is executed through several international standard such as IEC 61109 and CEA tracking wheel test, but is not getting clear conclusion yet. There are two methods in the diagnosis method of polymer insulator such as off-line and on-line. The diagnosis methods in off-line are external condition analysis by the eye, contaminant analysis on surface, surface analysis, pollution withstand voltage test, power frequency flashover voltage test, lightning impulse flashover test, tensile fracture load test and flexural load test. Polymer material is also investigated it's tracking resistance by adding surface active agent in IEC 587. In this paper, the tracking performance of polymer insulator with salt solution which is added surface active agent. The diagnosis of insulator sample has been analyzed by leakage current and visual examination, STRI guide and thermal image camera.