• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.800-807
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• 2001

This study was designed to investigate the antioxidative activity of a substance isolated from. The antioxidative activity of procyanidine was higher than that of dl-tocopherol and BHA on low-density lipoprotein (LDL) oxidation by thiobarbituric acid reactive substance (TBARS). Procyanidine inhibited the copper-mediated oxidation of human LDL in a dose dependent manner with almost complete inhibition at $60{\mu}g/mL$. Procyanidine at a concentration of $80{\mu}g/mL$ in hibited oxidation of LDL induced by J774. LDL oxidized by copper-mediated or cell-induced oxidation was degraded at a much greater rate than native LDL. These results suggested the importance of further research to procyanidine in the investigation of atherosclerosis and free radical-induced injury.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.151-155
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• 2008

Oxidation of low density lipoprotein (LDL) is regarded to play an important role in the development of atherosclerosis. In the present study, salad vegetables with a remarkable DPPH radical-scavenging activity were extracted with methanol, and the methanol extracts were evaluated for the inhibition of $Cu^{2+}$-induced oxidation of human LDL. Separately, the amount of total phenolics was determined colorimetrically using Folin-Ciocalteu reagent. The vegetable extracts, expressing a strong inhibition of LDL oxidation ($IC_{50}$ values, <$100\;{\mu}g/mL$), were from angelica, dandelion, mustard leaf, and water spinach, which contained relatively high level of polyphenol content. Noteworthy, a highly positive correlation was observed between inhibition of LDL oxidation and amount of total polyphenol (p<0.01). Based on these results, it is suggested that salad vegetables, especially angelica, dandelion, and mustard leaf, may be used as easily accessible sources of natural antioxidants, especially in anti-atherosclerosis.

• Journal of Life Science
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• v.12 no.3
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• pp.325-331
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• 2002

There is growing interest ill understanding the role and mechanisms of flavonoid as antioxidant on LDL. The antioxidative activity of flavonoid typically present in Oenothers odorate Jacquin was investigated in vitro using a human LDL oxidation assay. In present work, LDL was incubated with increasing concentrations of extracts of extracts of Oenothers odorate Jacquin and LDL oxidation was started by adding CuSO$_4$to the media. Substances in leaves extracts of Oenothers odorate Jacquin are capable of inhibiting the initiation and the propagation of LDL oxidation. They inhibit LDL oxidation, monitored by thiobarbituric acid-reactive substances(TBARS), as well as modification as shown through direct measurement of electrophoretic mobility, diene conjugates. Inhibition is a dose dependent effect that becomes already apparent at concentration of extracts as low as 40$\mu\textrm{g}$/mL. Inhibition is almost complete at 80$\mu\textrm{g}$/mL. Extracts of Oenothers odorate Jacquin were more potent antioxidative activity than either ascorbic acid and dl-a -tocopherol.

• YAKHAK HOEJI
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• v.45 no.5
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• pp.529-536
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• 2001

The root of Astragalus membranaceus Bunge (Leguminosae), which has been used for the treatment of hypertension, chronic hepatitis, duodenal ulcers, chronic nephritis and promotion of immunity in folk remedies. Several lines of evidence indicate that oxidative modification of low-density lipoprotein (Ox-LDL) may play an important role in atherogenesis. Hence, the role of antioxidants in the prevention of LDL oxidation needs to be determined. To investigate the antioxidant activity. we determined the MeOH ex. and fractions of Astragali Radix on the inhibition of LDL oxidation. The CH$_2$C1$_2$ and EtOAc orations inhibited the oxidative modification of LDL by a decrease in the lipid peroxide content and the electrophoretic mobility of LDL. Calycosin-7-0-$\beta$-D -glucoside which was isolated from EtOAc fraction inhibits the oxidative modification of LDL.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.342-348
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• 2001

Growing evidence indicates that oxidized low density lipoprotein (LDL) may promote atherogenesis. Therefore, inhibition of LDL oxidation may impede this process. The effect of chitin sulfate on the susceptibility of human low density lipoprotein (LDL) to macrophages-induced oxidation was investigated by monitoring a thiobarbituric acid reactive substance (TBARS). Chitin sulfate inhibited LDL oxidation by macrophages in a dose dependent manner, with a 50~100$\mu$M, as assessed by TBAaS assay. Chitin sulfate, at 100 $\mu$M, almost completely inhibited the macrophage-induced increase in electrophoretic mobility of LDL. Also, chitin sulfate almost completely inhibit $O_2$￣ at concentration of 100 $\mu$M. These observations suggest that chitin sulfate might be an effective in prevention of atherosclerosis.

• Archives of Pharmacal Research
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• v.28 no.10
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• pp.1156-1160
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• 2005

An iridoid glycoside, oldenlandoside III (5) was isolated from the n-butanol fraction of methanol extracts of the aerial parts of Oldenlandia diffusa Roxb. along with six others previously characterized iridoid glycosides; geniposidic acid (1), scandoside (2), feretoside (3), 10-O-ben-zoylscandoside methyl ester (4), asperulosidic acid (6) and deacetylasperulosidic acid (7). Compounds 1, 2, and 7 inhibited LDL-oxidation, and showed $63.3{\pm}2.0,\;62.2{\pm}1.6,\;and\;63.8{\pm}1.5\%$ inhibition, respectively, at a concentration of 20 ${\mu}g/mL$.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.254-259
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• 2011

Growing evidence indicates that oxidized low density lipoprotein (LDL) may promote atherogenesis. Therefore, inhibition of LDL oxidation may impede this process. The inhibitory effected on the susceptibility of human LDL to $Cu^{2+}$ or macrophages induced oxidation was investigated by monitoring thiobarbituric acid reactive substances(TBARS). Organosulfur compounds of garlic oil contains diallyldisulfide, diallyltrisulfide, diallyltetrasulfide, and diallyl pentasulfide in order. Garlic oil inhibited LDL oxidation by $Cu^{2+}$, or macrophages in a dose dependently, with a 20~60 ${\mu}g$, as increased TBARS assay. Garlic oil, at 60 ${\mu}M$, almost completely inhibited macrophages induced increase in electrophoretic mobility of LDL. When compared with several other antioxidants, probucol showed highest ability, and then garlic oil showed a much higher ability than natural occurring antioxidants, ${\alpha}$-tocopherol and ascorbic acid. The results suggested that garlic oil might play the inhibitory effects in the process of LDL oxidation.

• Journal of Life Science
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• v.14 no.1
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• pp.180-187
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• 2004

Crowing evidence indicates that oxidized low density lipoprotein (LDL) nay promote atherogenesis. Therefore, inhibition of LDL oxidation may impede this process. The effect of geraniin on the susceptibility of human low density lipoprotein (LDL) to macrophages-induced oxidation was investigated by monitoring a thiobarbiruric acid reactive substrance (TBARS). The antioxidative activity of geraniin was higher than that of $\alpha$-tocopherol on low density lipoprotein (LDL) oxidation by thiobarbituric acid reactive substance (TBARS). Geraniin inhibited the C $u^{2+}$ mediated oxidation of human LDL in a dose dependent manner at concentration of 50 and 100 $\mu\textrm{g}$/mL. Geraniin, almost completely inhibited the macrophages mediated LDL oxidation in electrophoretic mobility and conjugate diene of LDL oxidation. Also, geraniin almost completely inhibited 0$_2$$^{[-10]}$ at concentration of 100 $\mu\textrm{g}$/mL. The physiological relevance of the antioxidative activity was validated at the cellular level where geraniin inhibited endothelial cell mediated LDL oxidation, When compound with several other antioxidants geraniin showed a high activity equal to natural antioxidants, $\alpha$-tocopherol and ascorbic acid, and the synthetic antioxidant, protocol. These results indicate that geraniin might play a protective antioxidant effects on LDL, probably affecting both the structural properties of macrophage and endothelial cell for the LDL oxidation..

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.279-283
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• 2006

This study was conducted to examine the effect of polyphenols from safflower seed on HMG-CoA reductase (HMGR) activity, LDL oxidation and Apo A1 secretion from Hep3B cell. The safflower seed polyphenols were matairesinol (Iignan), enterolactone (lignan metabolite), acacetin (flavone) and serotonin derivative. In addition to safflower polyphenols, mevastatin, ${\alpha}-estradiol,\;{\alpha}-tocopherol$ and soy genistein were tested as reference compounds depending on the type of the test. HMGR source was liver microsome obtained from rat fed 2% cholestyramine for 10 days. Inhibition of HMGR activity was greater with mevastatin (53%) than safflower serotonin derivatives (45%), followed by genistein (35%), but was very small with matairesinol, enterolactone and acacetin. LDL oxidation induced by $CuSO_4$ was suppressed by all the test material used in the present study and in the order of safflower serotonin derivatives> matairesinol > ${\beta}-estradiol$ > genistein > acacetin > enterolactone. Apo A1 secretion from Hep3B cell was significantly stimulated by mevastatin, but moderately (p<0.1) by ${\beta}-estradiol$ and genistein as well as enterolactone. These results suggest that the safflower polyphenols improve body lipid status via inhibition of cholesterol synthesis and suppression of LDL oxidation.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.134-142
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• 1996

Diabetes carries an increased risk of atherosclerotic disease that is not fully explained by known car-diovascular risk factors. There is accumulating evidence that advanced glycation of structural proteins, and oxidation and glycation of circulating lipoproteins, are implicated in the pathogenesis of diabetic ather-osclerosis. Reactions involving glycation and oxidation of proteins and lipids are believed to contribute to atherogenesis. Glycation, the nonenzymatic binding of glucose to protein molecules, can increase the ather-ogenic potential of certain plasma constituents, including low density lipoptotein(LDL). Glycation of LDL is significant increased in diabetic patients compared with normal subjects, even in the presence of good glycemic control. Metabolic abnormalities associated with glycation of LDL include diminished recognition of LDL by the classic LDL receptor; increased covalent binding of LDL in vessel walls ; enhanced uptake of LDL by the macrophages, thus stimulating foam cell formation ; increased platelet aggregation; formation of LDL-immune complexes ; and generation of oxygen free radicals, resulting on oxidative damage to both the lipid and protein components of LDL and to any nearby macromolecules. Oxidized lipoproteins are characterzied by cytotoxicity, potent stimulation of foam cell formation by macrophages, and procoagulant effects. Combined glycation and oxidation, "glycoxidation" occurs when oxidative reactions affect the initial products of glycation, and results in irreversible structural alterations of proteins. Glycoxidation is of greatest significance in long lived proteins such as collagen. In these proteins, glycoxidation products, believed to be atherogenic, accumulate with advancing age : in diabetes, their rate of accumulate is accelerated. Inhibition of glycation, oxidation and glycoxidation may form the basis of future antiaterogenic strategies in both diabetic and nondiabetic individuals.dividuals.