• Korean journal of food and cookery science
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• v.15 no.6
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• pp.611-617
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• 1999

Commercial soybean oil, which did not contain any antioxidant, were autoxidized at $60{\pm}2^{\circ}C$ for 79 days, and the changes of peroxide value(POV), thiobarbituric acid value(TBAV), conjugated dienoic acid(CDA) content, and fatty acid composition of the oil were studied during the 79 day-storage period. The samples with POV S of 0, 150, 300, 500, 450, 400 and 300 meq./kg oil were used for the test of mutagenic activity. The Ames test was carried out with and without metabolic activation. Bacterial strains used in this study were the histidine auxotrophic strains of S. typhimurium TA100, TA1535, and TA102 for the detection of base pair, and TA98 and TA1537 for frame shift mutations. Each series of samples was disso1ved in tetrahydrofuran(inhibitor free) and tested at doses ranging from 0.05 to 5 mg/plate. The autoxidized soybean oil increased significantly(p<0.05) the number of $His^+$ revertant colonies in cases of TA 98 with S9 mix, TA100 without S9 mix, 1535 and 1537 with and without S9, respectively. The samples having the highest peroxide values showed the strongest mutagenicity. It seemed that the amount of hydroperoxides in the oils was closely related to the mutagenic activity of the respective oils.

• Applied Biological Chemistry
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• v.32 no.1
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• pp.30-36
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• 1989

Some chelating agents are evaluated as an antioxidant for the autoxidation of soybean oil. Soybean oil is autoxidized under a mild condition (the flow rate of 67ml $O_{2}/min$ and $50^{\circ}C$). The antioxidant effect is measured by active oxygen method, and the spectral change of autoxidized soybean oil examined. The antioxidant effect of chelating agents is increased in order of diphenic acid, naphthoquinone, pyromellitic acid, quinolinic acid and naphthalic acid, and particularly the effect is low in diphenic acid and naphthoquinone. It is found that the effect is more clearly demonstrated by NMR rather than IR and UV and that the effect is dependent on the functional group and geometric molecular structure of chelating agents.

• Applied Biological Chemistry
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• v.32 no.1
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• pp.37-43
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• 1989

Some phenolics were examined as an antioxidant for the autoxidation of soybean oil. Soybean oil was autoxidized under a mild condition (the flow rate of 67ml $O_{2}/min$ and $50^{\circ}C$). The antioxidant effect was estimated by active oxygen method. Phenolics show distinctive antioxidant effect, and the effect is prominent when cupper or iron was added. Phenolics showed a tendency to increase antioxidant effect with an increase of the number of hydroxyl group, and the increasing order was ferulic acid, quinalizarin, sesamol, alizarin, fisetin and purpurogallin. However, the effect was remarkably low in ferulic acid, alizarin and quinalizarin. It was found that the antioxidant effect was dependent on the functional group and geometric molecular structure of phenolics.

• The Korean Journal of Food And Nutrition
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• v.9 no.2
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• pp.137-142
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• 1996

To develop antioxidant substances in plant, phenolic compounds in Bangah (Igodon japonicus, Hara) and antioxidative effects of cell extracts were investigated. Defatted samples of Bangah were extracted with acetone/methanol and the extracts were fractionated Into the free and bound types of phenolics. The equal amounts of fractions were dissolved In soybean oil and autoxidized at 45$^{\circ}C$ for 25 days. Peroxide value and TBA values were determined every 5 days during oxidation. Changes of peroxide and TBA values showed antioxidant effects, which were lower than control during the oxidation periods. The effects of cell extracts were evaluated as high as BHT, 0.02 ppm. The antioxidative effect of insoluble-bound phenolic extract was higher than that of free. The contents of phenolic compounds in insoluble-bound fraction were also higher than free fraction.