45H-14 |
Antioxidant properties of sesame (Sesamum indicum) fractions |
C. M. LIYANA-PATHIRANA1, D. S. Wall, and F. Shahidi. (1) Department of Biology, Memorial University of Newfoundland, St. John's, NF A1B 3X9, Canada Foods of plant origin are known to provide a complex mixture of natural substances with antioxidative effects. Such antioxidant activity appears to be closely related to the prevention of degenerative diseases such as cancer, cardiovascular diseases, atherosclerosis and the process of aging, among others. This purpose of the study was to determine total phenolic content, total antioxidant status (TAS), free radical scavenging capacity and inhibition of low density lipoprotein (LDL) by whole black (WB) and whole white (WW) sesame seeds and their respective hull fractions (BH and WH). Phenolic constituents of sesame were extracted into 80% ethanol. Total phenolic content was determined according to Folin-Ciocalteu procedure and calculated as catechin equivalents. Free radical scavenging capacity of sesame extracts (5-40mg/mL) was measured using 2,2’-diphenyl-1-picrylhydrazyl (DPPH) radical. Total antioxidant activity was determined by trolox equivalent antioxidant capacity (TEAC) assay and expressed as trolox equivalents (TE). Inhibition of LDL oxidation was measured by incubating crude extracts with LDL and CuSO4 at 37C. Formation of conjugated dienes was determined at 25-100ppm levels of phenolics. Total phenolic contents of whole seed and hull of black sesame were 29.9±0.6 and 146.6±0.6 mg catechin equivalents/1g crude extract, respectively. The corresponding values for white sesame were 29.7±0.9 and 10.6±1.6 mg catechin equivalents/1g crude extract. TAS was highest with black sesame hulls {65.9±1.7TE} while white whole seed showed the lowest {4.4±0.6TE}. DPPH radical scavenging capacity at 40mg/mL was 94.9±0.8, 25.1±0.4, 14.4±0.9 and 2.5±0.4 for BH, BW, WH and WW, respectively. Inhibition of LDL oxidation at 100ppm level was highest for BH ((96.7) followed by 84.6, 78.4 and 57.3% for WH, BW and WW, respectively. Results demonstrate considerable antioxidant activity of sesame fractions especially black sesame hulls and their potential health benefits. Thus, sesame and its components may serve as viable natural sources of antioxidants for food and non-food applications.
Session 45H, International: General
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