• Preventive Nutrition and Food Science
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• 제9권2호
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• pp.167-173
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• 2004

The aim of this study was to investigate the antioxidant effect of medicinal plants used by diabetic patients. Fourteen medicinal plants were selected and antioxidant activity such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, inhibition effect of linoleic acid autoxidation and low density lipoprotein (LDL) oxidation, thiobarbituric acid (TBA) value were measured. The Cornus officinalis had DPPH radical scavenging activity of 84.79%, which was higher than the 78.79% for $\alpha$-tocopherol. Rosa rugosa Thunberg, Pueraria thundergiana Bentham, Artemisia princeps var. orientalis and Sasamorpha purpurascens Nakai also had high values. Extracts with higher DPPH radical scavenging activities had higher total phenol concentrations, and positive correlations between these parameters were found. Inhibitory activities of linoleic acid autoxidation, LDL oxidation and TBA value, used as indices of oxidative stress, were observed in most of the selected medicinal plants. The highest inhibitory activity for TBA value was observed in the extract of Pueraria thundergiana Bentham. Rosa rugosa Thunberg (75.50 %), Sasamorpha purpurascens Nakai (74.00 %), and Cornus officinalis (73.00 %) all had high antioxidant activity against linoleic acid autoxidation, similar to that of $\alpha$-tocopherol. The same 3 plants also had high in inhibitory activity against LDL oxidation. Therefore, we demonstrated that medicinal plants used as folk remedy by diabetic patients had antioxidant activity. Especially, Rosa rugosa Thunberg, Cornus officinalis, Pueraria thundergiana Bentham, Arlemisia princeps var. orientalis, and Sasamorpha purpurascens Nakai had high phenol concentrations which resulted in high values for DPPH radical scavenging. These same plants exhibited high values for inhibitory activities for TBA value, linoleic acid autoxidation and LDL oxidation, indices associated with lipid peroxidation.

• Applied Biological Chemistry
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• 제32권1호
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• pp.8-13
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• 1989

자동산화반응(自動酸化反應)의 Model화합물(化合物)로서 methyl linolenate를 시간별(時間別)로 상온과 90ml/min의 air flow rate하(下)에 96시간(時間)까지 산화(酸化)시켰다. 이들 산화반응물(酸化反應物)에 대(對)한 NMR측정치(測定値)로부터 반응속도상수(反應速度常數)와 반응차수(反應次數)를 산출(算出)한 결과(結果) methyl lino1enate의 자동산화(化自動酸化)는 일차(一次) 반응속도론(反應速度論)을 따르며, 그 반응속도상수(反應速度常數)는 $1.96{\times}10^{-2}hr^{-1}$이었다. 지방산(脂肪酸)의 자동산화(自動酸化)에 대(對)한 Kinetics연구(硏究)에 여러가지 방법(方法)이 이용(利用)되고 있으나 본실험결과(本實驗結果)로 보아 NMR가 보다 신속(迅速)하고도 효과적(效果的)인 분석방법(分析方法)이라고 생각된다.

• The Korean Journal of Physiology and Pharmacology
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• 제3권3호
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• pp.251-261
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• 1999

The effects of carnosine and related compounds (CRCs) including anserine, homocarnosine, histidine, and ${\beta}-alanine$ on monosaccharide autoxidation and $H_2O_2$ formation were investigated. The incubation of CRCs with D-glucose, D-glucosamine, and D, L-glyceraldehyde at $37^{\circ}C$ increased the absorption maxima at 285 nm, 273 nm, and $290{\sim}330$ nm, respectively. D, L-glyceraldehyde was the most reactive sugar with CRCs. The presence of copper strongly stimulated the reaction of carnosine and anserine with D-glucose or D-glucosamine. Carnosine and anserine stimulated $H_2O_2$ formation from D-glucose autoxidation in a dose-dependent manner in the presence of 10 ${\mu}M$ Cu (II). The presence of human serum albumin (HSA) decreased their effect on $H_2O_2$ formation. Carnosine and anserine has a biphasic effect on ${\alpha}-ketoaldehyde$ formation from glucose autoxidation. CRCs inhibited glycation of HSA as determined by hydroxymethyl furfural, lysine residue with free ${\varepsilon}-amino$ group, and fructosamine assay. These results suggest that CRCs may be protective against diabetic complications by reacting with sugars and protecting glycation of protein.

• 한국응용과학기술학회지
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• 제9권2호
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• pp.175-179
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• 1992

Methyl linoleate의 자동산화와 인지질에 작용하는 lipoxygenase의 활성에 미치는 탄닌산과 알파토코페롤의 영향을 HPLC로 조사하였다. 반응혼합물은 methyl linoleate 70mM, 라디칼 생성체 AMVN와 탄닌산 및 알파토코페롤 각각 0.7mM를 함유하였다. Hydroperxide 생성량을 측정하여 탄닌산과 알파토코페롤이 상당히 좋은 항상화제임을 알았고, 인지질 1${\mu}M$에 탄닌산과 알파토코페롤을 각각1${\mu}M$ 함유한 혼합물에 효소를 첨가하여 활성 억제효과를 측정하여, 탄닌산과 알파토코페롤이 좋은 효소 활성 억제작용을 하고 있음을 알았다.

• 한국식품영양과학회지
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• 제29권4호
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• pp.568-574
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• 2000

Phytofluene를 dichloromethane에 용해하고 dry ice 상에서 ozonolysis를 행하였다. Ozonolysis에 의해 생성된 화합물은 silica gel chromatography를 행 하여 분획하고, photodiode array detector를 이용하여 ODS-HPLC로 분석하였다. Phytofluene을 5% Tween 40 수용액에 용해하고 37$^{\circ}C$, 24시간 자동산화시킨 결과, 다수의 carbonyl 및 acidic 화합물의 생성되었다. Phytofluene의 자동산화로부터 생성된 carbonyl 화 합물의 대부분은 ozonolysis에 얻어진 산화개열산물이 나타내는 HPLC상의 거동과 분광학적 특성이 서로 잘 일치하였다. 또한 phytofluene의 자동산화에 의해 생성된 중앙개열 acidic 화합물은 생성활성을 나타내는 4,5-didehydrogeranyl geranyl acid 표준품과 동일한 분광학 적 특성을 나타냈다. 이러한 결과는 in vitro 상의 산화적 조건하에서 phytofluene의 자동산 화에 의해 eccentric cleavage가 생성됨을 알 수 있었다.

• Food Science and Biotechnology
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• 제16권6호
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• pp.981-987
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• 2007

Effects of lignan compounds (sesamol, sesamin, and sesamolin) extracted from roasted sesame oil on the autoxidation at $60^{\circ}C$ for 7 days and thermal oxidation at $180^{\circ}C$ for 10 hr of sunflower oil were studied by determining conjugated dienoic acid (CDA) contents, p-anisidine values (PAV), and fatty acid composition. Contents of lignan compounds during the oxidations were also monitored. ${\alpha}$-Tocopherol was used as a reference antioxidant. Addition of lignan compounds decreased CDA contents and PAY of the oils during oxidation at $60^{\circ}C$ or heating at $180^{\circ}C$, which indicated that sesame oil lignans lowered the autoxidation and thermal oxidation of sunflower oil. Sesamol was the most effective in decreasing CDA formation and hydroperoxide decomposition in the auto- and thermo-oxidation of oil, and its antioxidant activity was significantly higher than that of ${\alpha}$-tocopherol. Sesamol, sesamin, and sesamolin added to sunflower oil were degraded during the oxidations of oils, with the fastest degradation of sesamol. Degradation of sesamin and sesamolin during the oxidations of the oil were lower than that of ${\alpha}$-tocopherol. The results strongly indicate that the oxidative stability of sunflower oil can be improved by the addition of sesamol, sesamin, or sesamolin extracted from roasted sesame oil.

• Food Science and Biotechnology
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• 제14권3호
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• pp.424-427
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• 2005

The cleavage products formed by the autoxidation of phytofluene were evaluated in order to elucidate possible oxidation products of phytofluene in the oxidative condition. Among a number of oxidation products formed, the following five in the carbonyl compound fraction were identified: 6, 10, 14-trimethylpentadeca-3,5,9,13-tetraen-2-one, phytapentaenal, 5,9,13,17-tetramethyloctadeca-2,4,6,8,12,16-hexaenal, 5,9,13,17-tetramethyloctadeca-2,4,8,12, 16-pentaenal, 2,7,11,15,19-pentamethylicosa-2,4,6,10,14,18-hexaenal and 4,9,13,17,21-pentamethyldocosa-2,4,6,8,12,16,20-heptaenal. In addition, 4,5-didehydrogeranyl geranoic acid was formed by the autoxidation of phytofluene in liposomal suspension. The pig liver homogenate was able to convert phytapentaenal to 4,5-didehydrogeranyl geranoic acid, in a manner comparable to the conversion of all-trans-retinal to all-trans-retinoic acid. These results suggest firstly that phytofluene is cleaved into a series of long-chain and short-chain carbonyl compounds under the oxidative condition in vitro and secondly that phytapentaenal is further enzymatically converted to 4,5-didehydrogeranyl geranoic acid.

• 한국식품영양과학회지
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• 제33권1호
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• pp.123-131
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• 2004

단백질의 Maillard 반응의 최종산물의 하나인 $N^{\varepsilon}$-car-boxy methyl lysine(CML)의 형성에 미치는 reactive oxygen species(ROS)의 영향을 살펴보았다. Glucose와 fructose는 자동산화과정을 통하여 CML 형성의 주된 propagator인 $\alpha$-dicarbonyl 화합물은 물론 glyoxal을 생성시키는 것이 확인되었다. 또한 이 과정은 ROS를 형성하는 천이금속이온에 의해 촉진되는 산화과정임을 알 수 있었다. 반응성이 높은 fructose에 비해 glucose의 경우가 ROS의 영향이 더욱 현저하게 나타났다. 불포화 지방산도 glyoxal을 형성하고 있었으며, 불포화도가 클수록 glyoxal 생성량이 빠르게 나타났으나 ROS의 영향은 비교적 작게 나타났다. Ascorbic acid 역시 ROS와는 무관하게 glyoxal을 생성하였다. 이는 ROS의 영향이전에 이들 물질들의 반응성이 매우 높다는 것을 의미하고 있다. Hippury lysine을 이용한 model system에서도 glucose로부터의 $N^{\varepsilon}$-carboxymethyl hipuryllysine(CMHL) 형성에서는 ROS의 영향이 높게 나타났으나, 반응성이 매우 높은 glyoxal에 의한 CMHL 생성에는 ROS의 영향이 거의 나타나지 않았다. CML에 특이적으로 결합하는 monoclonal antibody(6D12)를 이용한 antigen coated noncompetitive indirect ELISA 분석을 통해서 CML생성에 미치는 ROS의 영향을 살펴본 결과 대체로 위의 결과와 비슷한 경향을 나타내었다. 따라서 반응성이 높은 물질일수록 CML 형성에 ROS의 영향이 작게 나타남을 알 수 있었다.

• 식품산업과 영양
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• 제5권2호
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• pp.65-69
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• 2000

• International Journal of Safety
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• 제9권1호
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• pp.43-46
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• 2010

In the recycle process of organic solvent, the atmospheric oxygen can cause autoxidation and product peroxide. The time-saving method to evaluate the hazards has been required. In this study, oxygen pressure monitoring experiment was proposed as a new method to evaluate autoxidative resistances of solvents. Some of organic solvents were pressurized by oxygen and kept under isothermal condition. At the same time, the pressure in the vessel tracked. Iodometrical titration, thermal analysis and spectroscopic analysis were performed to measure peroxide concentration, the heat of reaction and chemical bonding change. From the results that THF has larger oxygen consumption rate than CPME, it is considered that autoxidative resistance of THF is lower than that of CPME. This method enables to obtain results in shorter time than other methods. These experimental results were consistent with the previous research with longer test durations [1-2].