• 동아시아식생활학회지
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• 제27권2호
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• pp.194-203
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• 2017

Mealworm, a type of edible insect, is a superior food material suitable for industrial products. In this study, four different defatted mealworm powders were prepared to determine proper manufacturing conditions. Solvent extraction method reduced lipid contents of mealworms more than pressed mealworms, and lowered lipid contents caused bright colors and good physicochemical properties for powders. In comparison, differences among milling machines used for making powders were strongly related with average size of particles. Meanwhile, the predicted shelf-life of defatted mealworm powders judged by accelerated experiments was 1 year or longer. To enhance shelf-life of mealworm powders, addition of tocopherol to mealworm powders at a concentration of 0.2% could intensify oxidative stability and microbial inhibition.

• 생약학회지
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• 제37권1호통권144호
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• pp.60-66
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• 2006

Norditerpene alkaloids are the main toxic principles of traditional oriental herb 'chuawu(bu-shi),' which have been used in Chinese materia medica mainly for the treatment of musculoskeletal disorders. They are biosynthesized via cyclization of geranylgeranyl pyrophosphate, incoration of 2-aminoethanol and decarboxylation not via amino acid pathway, and the structural characteristics have tempted several oxidative reactions. In this study various norditerpene alkaloids were subjected to react active manganese dioxide and oxoammonium salt as oxidants. The oxidation was proceeded as dealkylation with aconitine type and dehydrogenations with lycoctonin and heteratisine type.

• 생물정신의학
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• 제5권2호
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• pp.235-242
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• 1998

Objectives : Alcohol-induced oxidative stress has been known to injure various tissues or organs. This stress is related with free radicals which are produced as the result of long-term alcohol consumption. Malonyldialdehyde(MDA) is produced by the interaction of free radicals and cell membrane lipids, and indicates the degree of lipid peroxidation indirectly. The purpose of this study was to investigate the relationship between red blood cell(RBC) membrane lipid peroxidation by free radicals, and associated hepatic injuries and hematologic changes. Methods : Thirty-three subjects diagnosed as alcohol dependence according to DSM-IV diagnostic criteria were evaluated within 72 hours after discontinuing alcohol drinking. Clinical characteristics were evaluated by CAGE questionnaire and Korean Michigan Alcoholism Screening Test(MAST). RBC membrane MDA level was measured as the marker of RBC membrane lipid peroxidation. Aspartate aminotransferase(AST), alanine aminotransferase(ALT) and gamma-glutamyltransferase(GGT) were used as the biochemical markers of liver damage due to alcohol ingestion. The alcohol-induced hematologic change was assessed by mean corpuscular volume(MCV). Results : The results were as follows. Clinical characteristics were not different between two groups having normal and abnormal levels of AST, ALT, GGT or MCV. The levels of MDA were not correlated with the clinical characteristics and serum levels of AST, ALT and GGT. However, there was a significant correlation between the levels of MDA and the value of MCV(p=0.017). Conclusions : These findings suggest that oxidative stress in alcohol dependence may not be reflected in liver enzyme markers such as AST, ALT and GGT, but may be reflected in MCV.

• 동아시아식생활학회지
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• 제27권3호
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• pp.304-312
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• 2017

This study was carried out to evaluate the effects of yam powder addition (0~40%) on the quality characteristics and oxidative stability of yackwa made with rice flour. While most rice flour (34.35%) had a particle size more than $250{\mu}m$, 75% of yam powder had a particle size less than $65{\mu}m$. Width, height, and volume of rice yackwa added with yam powder increased with increasing yam powder content. While L and b values of rice yackwa added with yam powder decreased with increasing yam powder content, a value increased. Hardness and chewiness of rice yackwa added with yam powder increased as storage period increased at $25^{\circ}C$ for 9 days, whereas they decreased with increasing yam powder content. In a discrimination test, brown color, flavor, sweetness, and bitterness increased with increasing yam powder content, whereas hardness decreased. In a preference test, taste, texture, and overall acceptance increased with increasing yam powder content. The acid and thiobarbituric acid (TBA) values of rice yackwa added with yam powder increased as storage period increased. However, acid and TBA values of the treated groups decreased with increasing yam powder content compared to the control group. Although 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activities decreased with increasing storage period, values increased with increasing yam powder content. It was found that yackwa quality, preference, and oxidative stability increased during storage with increasing yam powder content. From these results, addition of 40% yam powder would be the optimal conditions for making rice yackwa.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2005년도 춘계학술대회
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• pp.53-60
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• 2005

Parkinson's disease (PD) is a progressive neurodegenerative disorder affecting $1\%$ of the population above the age of 65 and is characterized by a selective loss of dopaminergic neurons in the substantia nigra pars compacta. Although the underlying cause of dopaminergic cell death or the mechanism by which these cells degenerate is still not clearly understood, oxidative stress, mitochondrial dysfunction, and protein misfolding are thought to play important roles in the dopaminergic degeneration in PD. Tetrahydrobiopterin (BH4) is synthesized exclusively in the monoaminergic, including dopaminergic, cells and serves as an endogenous and obligatory cofactor for syntheses of the potential oxidative stressors dopamine and nitric oxide. In addition to its contribution toward the syntheses of these two potentially toxic molecules, BH4 itself can directly generate oxidative stress. BH4 undergoes oxidation during the hydroxylation reaction as well as nonenzymatic autooxidation to produce hydrogen peroxide and superoxide radical. We have previously suggested BH4 as an endogenous molecule responsible for the dopaminergic neurodegeneration. BH4 exerts selective toxicity to dopamine-producing cells via generation of oxidative stress, mitochondrial dysfunction, and apoptosis. BH4 also induces morphological, biochemical, and behavioral characteristics associated with PD in vivo. BH4 as well as enzyme activity and gene expression of GTP cyclohydrolase I, the rate-limiting enzyme in BH4 synthesis pathway, are readily upregulated by cellular changes such as calcium influx and by various stimuli including stress situations. This points to the possibility that cellular availability of BH4 might be increased in aberrant conditions, leading to increased extracellular BH4 subsequent degeneration. The fact that BH4 is specifically and endogenously synthesized in dopaminergic cells, Is readily upregulated, and generates oxidative stress-related cell death provides physical relevance of this molecule as an attractive candidate with which to explain the mechanism of pathogenesis of PD.

• 대한한의학회지
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• 제23권4호
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• pp.140-150
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• 2002

Objectives: The water extract of Omija-tang (OMIT) has traditionally been used for treatment of ischemic heart and brain damage in oriental medicine. However, little is known about the mechanism by which the water extract of OMJT rescues cells from these damages. Therefore, this study was designed to investigate the protective mechanisms of OMJT on oxidative stress-induced toxicity in H9c2 cardiomyoblast cells. Methods: Treatments of $H_2O_2$, or $ZnC_{12}$ markedly induced death of H9c2 cardiomyoblast cells in a dose-dependent manner. The characteristics of oxidative stress-induced death of H9c2 showed apparent apoptotic features such as DNA fragmentation. OMJT significantly reduced both ${H_2O_2}-induced$ cell death and chromatin fragmentation. The decrease of B치-XL expression by $H_2O_2$ were inhibited by OMJT. In addition, the increase of Bcl-XS expression was also inhibited by OMJT. In particular, Fas expression, which is generally recognized as cell death-inducing signal by Fas/FasL interaction, was markedly increased by H2O2 in a time-dependent manner. Also, the expression profile of proteins in Chang cells were screened by using two-dimensional (2-D) gel electrophoresis. Among 300 spots resolved in 2-D gels; the comparison of control versus apoptotis cells revealed that signal intensity of 6 spots decreased and 11 spots increased. Results and Conclusions: Taken together, this study suggests that the protective effects of the water extract of OMJT against oxidative damages may be mediated by the modulation of Bcl-XL/S Fas expression.

• 대한한의학회지
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• 제25권3호
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• pp.149-159
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• 2004

Backgrounds & Objectives : The water extract of Gyungokgo (GOG) has traditionally been used for treatment of general weakness and hemoptysis in oriental medicine. However, little is known about the mechanism by which the water extract of GOG rescues cells from these damages. This study was designed to investigate the protective mechanisms of GOG on H2O2­induced cell death in H9c2 cardiomyoblasts. Methods : In this study, we used H9c2 cells. Cells were treated with oxidative stress in the absence and presence of 1000㎍/ml GOG for 12hrs. Cells were treated with various concentrations of GOG for 12hrs. Cell viability was measured by MTT assay. Oxidative stress, which markedly decreased the viability of H9c2 cells, was characterized by apparent apoptotic features such as chromatin condensation as well as fragmentation of genomic DNA and nuclei. Results : GOG significantly reduced H₂O₂-induced cell death and apoptotic characteristics. The cotreatment of GOG and H₂O₂ in H9c2 cells also induced the phosphorylation of ERKs in a time-dependent manner. Moreover, PD098059, a MEK1 (upstream activator of ERK) inhibitor attenuated the protective effect of GOG on H₂O₂-induced cytotoxicity in H9c2 cardiomyoblast cells. Conclusions : These results suggest that MEK/ERK pathways play important roles in the protective effects of GOG in H9c2 cells. Taken together, they suggest that the protective effects of the water extracts of GOG against oxidative damages may be mediated by the regulation of HO-1, Fas/FasL and Bcl-XS proteins.

• Korean Chemical Engineering Research
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• 제46권5호
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• pp.845-851
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• 2008

티타늄이 그라프팅(grafting)된 SBA-15 촉매(Ti-grafted SBA-15)상에서 TBHP(tert-butylhydroperoxide)를 산화제로 사용하여 회분식 반응기에서 모델 황화합물 및 실제 디젤 유분(LCO; Light Cylcle Oil)의 선택산화탈황(ODS; Oxidative Desulfurization) 반응을 수행하였으며, 티타늄 함량, 산화제/황의 몰비, 반응온도의 효과 및 반응속도상수와 활성화 에너지를 조사하였다. 티타늄이 5 wt% 도입된 Ti-grafted SBA-15 촉매는 난분해성 황화합물인 디벤조티오펜(DBT; Dibenzothiophene)과 4, 6-디메틸디벤조티오펜(4, 6-Dimethyldibenzothiophene)의 설폰(sulfone) 화합물로의 산화반응 시 표준반응조건(TBHP/S=2.5, $80^{\circ}C$, 1 atm)에서 반응개시 후 20분 뒤 100% 전환되는 우수한 활성을 나타내었다. 실제 디젤유분인 LCO를 원료로 성능 시험을 한 결과 활성이 우수하게 나타났으며 Ti-grafted SBA-15 촉매는 LCO에 함유 되어 있는 난분해성 황화합물의 선택적 산화탈황촉매로써 응용 가능성을 보였다.

• 한국식품영양학회지
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• 제9권4호
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• pp.504-508
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• 1996

들깨를 15$0^{\circ}C$에서부터 21$0^{\circ}C$까지 10~30분간 볶아서 착유한 들기름에 존재하는 갈색물질의 갈색도와 전자제공력과, 또한 기호성 및 산화 안정성을 검토하였다. 들기름으로 추출한 갈색물질은 들깨의 볶는 온도와 시간이 증가에 따라 증가하였다. 들깨를 210~에서 30분간 볶아 착유한 들기름으로부터 추출한 갈색물질은 15$0^{\circ}C$에서 10분간 볶은 것에 비해 13배 정도 증가하였다. 한편 볶음조건에 따라 착유한 들기름 중의 갈색물질 추출물의 DPPH에 대한 전자제공력은 볶음온도와 시간 증가에 따라 향상되었다. 21$0^{\circ}C$에서 30분 볶아 착유한 들기름중의 갈색물질은 15$0^{\circ}C$에서 10분 볶은 것에 비해 전자제공력이 약 3배 증가하였다. 기호성이 가장 우수한 들기름에 산화 안정성이 가장 좋은 들기름을 5~20% 혼합한 15% 혼합량 것 중 기호도와 산화 안정성이 가장 우수하였다. 21$0^{\circ}C$에서 30분 볶아 착유한 들기름 중의 갈색물질은 19$0^{\circ}C$에서 20분 볶아 착유한 들기름의 산화 안정성을 증가시켰다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.650-650
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• 2013

Although imprinted nanopatterns of organic polymer can be modified by the heat treatment [1], it generally requires high process temperatures and is material-dependent since the heat-induced mass loss of the organic polymer is greatly affected by its chemical characteristics. When oxygen is added during the annealing process, one can reduce the process temperature as well as the dependence of the materials. With the oxygen, line width reduction of a polymer (SU-8) patterns could be accomplished at temperature of as low as $250^{\circ}C$ which was not possible in the heat only process. This oxidative line width reduction can be dramatically promoted with the introduction of oxygen plasma. The oxygen plasma, with its highly-reactive oxygen species, vigorously etches away the organic materials, proven to be extremely effective line with reduction method. It is, however, very hard to control the extent and homogeneity of the etching, particularly of very fine patterns. Here, we report an effective and reliable line width reduction method of imprinted nanopatterns by combined plasma and heat treatment. The merits of this process include the reduction of process temperature, time and material-dependence.