67B-13 |
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J. LEE and E. Choe. Department of Food and Nutrition, Inha University, 253 Younghyundong Namgu, Department of Food and Nutrition, Incheon, 402-751, South Korea Lignan compounds in sesame oil include sesamol, sesamolin, and sesamin. They have been known to prevent free radical-mediated tissue damage and decrease pathogenesis of many degenerative diseases. Although higher oxidation stability of sesame oil than other oils was shown, few systematic studies on the effects of lignans on the oil oxidation have been reported. This study investigated the effects of lignans during autoxidation of methyl linoleate as a model system of oils. About 200 mg of methyl linoleate was put into a rancimat reaction bottle, and 50, 100, or 200 ppm of sesamol, sesamin, or sesamolin was added. Sample bottles in duplicate were placed in a 40oC incubator with an air open system for 24 h. Oxidation of methyl linoleate was determined by conjugated dienoic acid (CDA) contents and p-anisidine value (PAV) according to the AOCS official methods. Contents of methyl linoleate and lignans were analyzed by gas chromatography and high performance liquid chromatography, respectively. CDA contents and PAV of methyl linoleate without lignans during autoxidation increased from 0.63 and 4.12 to 3.52 and 826.94 as oxidation time increased from 0 h to 24 h. Addition of sesamol, sesamin, and sesamolin showed lower CDA contents and PAV in methyl linoleate. As the concentration of sesamol, sesamin, and sesamolin increased, CDA contents and PAV of methyl linoleate decreased. The lowest CDA and PAV were observed in the sample containing 200 ppm sesamol. More methyl linoleate were remained in samples containing sesamolin, sesamin, and sesamol in an increasing order. Lignan contents in samples decreased as oxidation time increased. Sesamol showed the fastest decomposition among lignans. This study clearly showed that sesamol, sesamin, and sesamolin improved the autoxidative stability of methyl linoleate and the antioxidant activity of sesamol was higher than those of sesamin or sesamolin.
Session 67B, Food Chemistry: Antioxidants and bioactive agents
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