• Journal of Food Hygiene and Safety
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• v.14 no.2
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• pp.153-159
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• 1999

This study was undertaken to evaluate antioxidative activities of substances isolated from marine resources against human low density lipoprotein (LDL). Methanol-water extract(80 : 20, v/v) of Sargassum ringgoldianum had the highest antioxidant activity and the active substance was purified by silica gel column chromatography by eluting chlorform : methanol mixture (80 : 20 v/v). The active fraction was seperated to several spots on the TLC in chlorofrom : methanol (10 : 1, v/v) mixture. Antioxidative activity of band 4 of fraction 2 on TLC was highest than that of $\alpha$-tocopherol against human LDL oxidation by the method of thiobarbituric acid reactive substance (TBARS). The band 4 of fraction 2 inhibited the copper mediated oxidation of human LDL with almost completely at 1 or 2 mg/ml.

• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.138-146
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• 2004

This study was designed to investigate antioxidative activity of substances isolated from 25 kinds of useful plants resources toward free radical and human low density lipoprotein(LDL). Methanol extracts of Oenothers odorate had the highest antioxidative activity similar with ${\alpha}$-tocopherol. Methanol extracts of Oenothers odorate was extracted again by the ethylacetate. The ethylacetate soluble acidic fraction obtained from methanol extract of Oenothers odorate showed highest activity toward human LDL. Each fraction was purified through Sepadex LH-20 chromatography by elution of chloroform-methanol mixture (90:10 v/v). Fraction, F-2 obtained from Oenothers odorate showed at highest levels of electron donating activity. Fraction, F-2 was identified as 3,4-dihydroxybenzoic acid and 3-hydroxycinnamic acid.

• Journal of Life Science
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• v.8 no.4
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• pp.353-359
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• 1998

This study was initiated to antioxidant activity of silybin on oxidation of human low density lipoproteins(LDL). Siltbin was extracted from Silybum marianum by the combination of fractionation and it was futher purified by silica gel column chromatography, and isolated active substances were identified silybin by IR, NMR and GC-MS. siltbin inhibited the ozidation of human low density lipoprotein(LDL) mediated by 5$^{\mu}$m CU $^{2+}$ ion in a dose dependent manner. LDL oxidation by congugated dines formation was completely inhibited by silybin at a concentration of 5$^{\mu}$M. The results provide a possibility that silybin might protect LDL against oxidation in atherosclerotic lessions.

• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.1-8
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• 1997

This study was performed to evaluate the antioxidant activity of silymarin against human low density lipoproteins(LDL) oxidation. Silymarin extracted from Silybum marianum was successively purified with solvent fractionation and followed by silica gel column chromatography. The active substances were separated by HPLC and the isolated active substances, silymarin were identified by IR, NMR, GC-MS as silymarin. Silymarin inhibited at the 5 $\mu$M Cu2+-mediated oxidation of human low density lipoprotein (LDL) in a dose dependent manner. Silymarin completely inhibited LDL oxidation at 50 $\mu\textrm{g}$/$m\ell$ concentration. These findings suggest that silymarin may protect LDL against oxidation in atherosclerotic lessions.

• Journal of Life Science
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• v.17 no.10
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• pp.1330-1335
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• 2007

This study was developed to assess the antioxidative activity of aged black garlic extract on lipid peroxidation and low density lipoprotein (LDL). Antioxidative activity of aged black garlic extract on human low density lipoprotein (LDL) was investigated by monitoring a barbituric acid reactive substance (TBARS). Electron donating ability (EDA) of aged black garlic, ethanol extract was higher than that alliin and water extract. Aged black garlic water and ethanol extracts inhibited the $Cu^{2+}$ mediated oxidation of human LDL in a dose dependent manner at concentration of 10 and $20\;{\mu}g/ml$. Ethanol extract and water extract of aged black garlic almost completely inhibited J774 mediated LDL oxidation in electrophoretic mobility and conjugated diene. These results indicate that aged black garlic might play a protective antioxidant effects on LDL, probably affecting the structural properties for the LDL oxidation.

• KSBB Journal
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• v.15 no.2
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• pp.156-161
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• 2000

This study was designed to investigate the antioxidative activity on oxidation of human low density lipoprotein(LDL) of band 2 fractionated from culture broth of Streptomyces sp. BH-405. Antioxidative activity of band 2 obtained from fractionation of BH-405 culture purification was measured against $Cu^{2+}$ mediated human LDL oxidation by thiobarbituric acid reactive substance. $CuSO_4$ mediated oxidation of LDL was degraded at a much higher rate than native LDL. Band 2 at a concentration of 100 or 200 !lg/mL inhibited the oxidation of LDL induced by $CuSO_4$, The formation of conjugated dienes induced in the presence of 5 !1M CuS04 of the mouse macrophage and J744. The electrophoretic mobility of the LDL in addition of $200\mu\textrm{g}$ band 2 in the presence of $5\mu\textrm{m}$ $CuSO_4$ was lower than that of native LDL. LDL modified by copper mediated or cell mediated uptake was degraded by macrophage at much greater than native LDL, and band 2 was found as potential inhibitor of modification of 125I-labelled LDL by macrophage. phage.

• Journal of Life Science
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• v.7 no.4
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• pp.289-296
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• 1997

Antioxidative activity of fraction extracted from cultivation of Aspergillus sp. A-5 against oxidation of human low density lipoprotein(LDL) was investigated. Fractions of Aspergillus sp. A-5 cultivation was sucessively purified with ethyl acetate and silica gel column chromatography. The concentration of fraction 4 inhibited Cu$^{2+}$-induced oxidation of LDL almost completely. Band 3 isolated by the further purification of fraction 4 was higher than that of same concentration of $\alpha$-tocopherol, BHA and BHT. The elcetrophoretic mobility of oxidized LDL by addition of Band 3 was faster than that of native LDL, but slower than that of oxidzed LDL. It is concluded that fraction of Aspergillus cultivation contained antioxidants with the capacity to inhibit oxidative modification of LDL.

• Journal of Food Hygiene and Safety
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• v.13 no.1
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• pp.6-13
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• 1998

This study was carried out to investigate the antioxidative activity on oxidaton of human low density lipoprotein from marine microorganisms. Bacillus sp. RH-5 producing antioxidative activity have been isolated and identified from coast sea in Pusan. Bacillus sp. RH-5 produced at highest level of antioxidative activity in the medium of 1.0% glucose, 0.25% polypepton, 0.25% yeast extract, 0.01% $FeSO_4{\cdot}7H_2O$ and 50% sea water. The optimal medium pH, cultural temperature and shaking time for the highest production as the antioxidant were 7.0, $30^{\circ}C$ and 48 hr, respectively. The culture broth inhibited the copper catalyzed oxidation of human low density lipoprotein (LDL) at the concentration of 500 and $1,000\;\mu\textrm{g}/ml$ ethylacetate extracts in the presence of $5\;\mu\textrm{M}\;CuSo_4$. The electrophoretic mobility of the LDL oxidized in the presense of $5\;\mu\textrm{M}\;CuSo_4$ was higher than that of native LDL.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.286-292
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• 1997

This study was undertaken to evaluate an antioxidative activity of silymarin and silybin obtained from Silybum marianum against oxidation of human low density lipoprotein (LDL). The electrophoretic mobility observed apparently was higher phase for LDL oxidized by macrophages compared to native LDL. Silymarin and silybin inhibited the copper-catalysed oxidation of human LDL in a dose-dependent manner. Silymarin and silybin at the concentration of 50 $\mu$M/ml also inhibited the copper catalysed oxidation of LDL induced by the cell J774 and macrophages. LDL reisolated from the cell incubation in the presence of silymarin or silybin was degraded at rates similar with native LDL. Silymarin or silybin found to be potential inhibitors against oxidation of $^{125}$I-LDL by macrophages and endothelial cells.

• Journal of Life Science
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• v.22 no.12
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• pp.1712-1717
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• 2012

Oxidation of low density lipoprotein (LDL) plays an important role in the development and progression of atherosclerotic disease. In this study, human LDL was isolated and oxidized using $CuSO_4$ in the presence or absence of S-allylmercaptocysteine. Oxidative modification of the LDL fraction was monitored by both the appearance of thiobarbituric acid substances (TBARS), an increase in electrophoretic mobility, and conjugated diene formation. The addition of S-allylmercaptocysteine reduced lipid peroxide formation, indicating it to be an effective antioxidant. The inhibition of LDL oxidation by $5{\sim}20{\mu}g/ml$ S-allylmercaptocysteine occurred in a dose-dependent manner, as assessed by the TBARS assay. S-allylmercaptocysteine at $20{\mu}g/ml$ almost completely inhibited the $Cu^{2+}$ induced increases in electrophoretic mobility of LDL and almost completely inhibited conjugated diene formation. A more potent antioxidative activity was observed for S-allylmercaptocysteine than for either Vitamin C or $d{\ell}-{\alpha}$-tocopherol. Thus, S-allylmercaptocysteine aid in preventing the development and progression of atherosclerotic disease.