Antioxidants sesame

Several other naturally occurring antioxidants have been identified in oils. Sesamol [533-31-3] (6) occurs as sesamoline [526-07-8], a glycoside, in sesame seed oil. FemUc acid [1135-24-6] (7) is found esterified to cycloartenol [469-38-5] in rice bran oil and to 3-sitosterol in com oil. Although it does not occur in oils, rosemary extract has also been found to contain powerful phenoHc antioxidants (12). 

Effect of excessive intake of thermally CN158 oxidized sesame oil on lipids, lipid peroxidation and antioxidants status in rats. Indian J Exp Biol 2000 38(8) ... 

Osawa, T., M. Nagata, M. Namiki, and Y. Fukuda. Sesaminol, a novel antioxidant isolated from sesame seeds. Agr Biol Chem 1985 49(11) 3351-3352. Ogasawara, T., K. Chiba, and M. Tada. Production in high yield of naphthoquinone by a hairy root culture of Sesamum indicum. Phytochemistry 1993 33(5) 1095-1098. 

T. Ozaki. Studies on antioxidative sub- SI132 stances in sesame seed. AgrBiol Chem... 

Katsuzaki, H., M. Kawasumi, S. Kawa-kishi, and T. Osawa. Structure of novel antioxidative lignan glucosides isolated from sesame seed. Biosci Biotech Biochem 1992 56(12) 2087-2088. Chen, E. C. F., S. S. K. Tai, C. C. Peng, and J. T. C. Tzen. Identification of three novel unique proteins in seed oil bodies of sesame. Plant Cell Physiol... 

Yamasaki, S., Manh, L.H., Takada, R., Men, L.T., Dung, N.N.X., Khoa, D.V.A. and Taniguchi, T. (2003) Admixing synthetic antioxidants and sesame to rice bran for increasing pig performance in Mekong Delta, Vietnam. Japan International Research Center for Agricultural Science, Research Highlights 38-39. 

Fukuda, Y., Nagata, M., Osawa, T. and Namiki, M. (1986a) Contribution of lignan analogs to antioxidative activity of refined unroasted sesame seed oil. J. Amer. Oil Chem. Soc., 63(8), 1027—1033. 

Lignans of flaxseed exist as secoisolariciresinol diglucoside (SDG 126). SDG is a potent antioxidant in biological systems because of its tendency to associate in the aqueous phase. Much of the work on antioxidant activity of SDG is related to its radical mediated disease prevention (127, 128). Lignans of both sesame (121, 122) and flax (129, 130) have shown hydrogen-donating abihty and scavenging activity for various free radicals. 

In this chapter, the properties and processing of sesame oil will be presented, and the antioxidative components and their effects on oil stability and health will be summarized. 

Effect of Roasting on Antioxidative Activity Roasted sesame oU was reported to be much more antioxidative than unroasted purified sesame oil (71). Yen and Shyu (67) found that roasted sesame oUs prepared from sesame seeds with different roasting temperatures (between 180°C and 210°C) exhibited... 

Effect of Roasting on Different Ciasses of Lipids Roasting of sesame seed not only affects the antioxidative activity and the hgnans of sesame oil, the lipid composition will also be affected. The lipids in sesame seeds consist of neutral lipids, phosphohpids, and glycolipids. The major lipid fraction is neutral lipids, which constitute about 91 96% of the total lipids. Phospholipids and glycolipids represent around 3% and 0.3 6% of the total lipids, respectively (69, 70, 75-78). 

Alternatively, unroasted sesame seeds are pressed once followed by solvent extraction to recover the oil from residue. The oxidative stability of sesame oil was found to be dependent on the extraction method and seed pretreatment (64). Extraction of the sesame seeds after effective seed crushing with polar solvent, heptane-isopropanol (3 1, v/v), would yield a more stable oil from whole sesame seeds because more antioxidative substances and phospholipids could be extracted. Phospholipids may act as synergists to antioxidants (81). 

Sesamolin is first decomposed to sesamol by protonolysis to form an oxonium ion, and then the carbon-carbon bond is formed thus, it is hypothesized that sesa-minol is formed from sesamolin by intermolecular group transformation (91). The conversion of sesamolin to sesamol and sesaminol is illustrated in Figure 10. Both sesamol and sesaminol are strong antioxidants they contribute to the superior oxidative stability of refined or roasted sesame oil. 

Vitamin E is the common name for o-a-tocopherol and is an oily liquid at room temperature and is also an antioxidant. Alfacalcidol, a dehydroxy derivative of calcitriol, is formulated as a solution in a mixture of sesame oil and a-tocopherol in 0.25 pg, 0.5 pg, and 1.0 pg One-Alpha soft gelatin capsules. Ethyl icosapen-tate is used in the treatment of hyperlipidemia and arteriosclerosis obliterans, and exists as a liquid at ambient room temperature that is formulated as a solution in a-tocopherol in 300 mg Epadel soft gelatin capsules. 

Sesame oil is more stable than most other fixed oils and does not readily become rancid this has been attributed to the antioxidant effect of some of its characteristic constituents. The PhEur 2005 permits the addition of a suitable antioxidant to sesame oil. 

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