• Title/Summary/Keyword: Alkoxyl radical

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Mechanism of Lipid Peroxidation in Meat and Meat Products -A Review

  • Min, B.;Ahn, D.U.
    • Food Science and Biotechnology
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    • v.14 no.1
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    • pp.152-163
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    • 2005
  • Lipid peroxidation is a primary cause of quality deterioration in meat and meat products. Free radical chain reaction is the mechanism of lipid peroxidation and reactive oxygen species (ROS) such as hydroxyl radical and hydroperoxyl radical are the major initiators of the chain reaction. Lipid peroxyl radical and alkoxyl radical formed from the initial reactions are also capable of abstracting a hydrogen atom from lipid molecules to initiate the chain reaction and propagating the chain reaction. Much attention has been paid to the role of iron as a primary catalyst of lipid peroxidation. Especially, heme proteins such as myoglobin and hemoglobin and "free" iron have been regarded as major catalysts for initiation, and iron-oxygen complexes (ferryl and perferryl radical) are even considered as initiators of lipid peroxidation in meat and meat products. Yet, which iron type and how iron is involved in lipid peroxidation in meat are still debatable. This review is focused on the potential roles of ROS and iron as primary initiators and a major catalyst, respectively, on the development of lipid peroxidation in meat and meat products. Effects of various other factors such as meat species, muscle type, fat content, oxygen availability, cooking, storage temperature, the presence of salt that affect lipid peroxidation in meat and meat products are also discussed.

Mild Isomerative Opening of Tetrahydrofuranyl Subunits in Steroids Using TFAT (trifluoroacetyl trifluoromethanesulfonate): Application to Synthesis of C17-OH Rockogenin Acetate

  • Lee, Jong-Seok;Kim, Byung-Sook;Shin, Jun-Ho;Lee, Yeon-Ju;Shin, Hee-Jae;Lee, Hyi-Seung
    • Bulletin of the Korean Chemical Society
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    • v.33 no.1
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    • pp.76-82
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    • 2012
  • A novel and efficient tetrahydrofuranyl ring opening method was developed using the highly reactive TFAT reagent in the presence of an acid scavenger, 2,6-di-tert-butyl-4-methylpyridine. Various acid sensitive groups are compatible with the reaction condition, making it generally applicable to many tetrahydrofuranyl steroids. Moreover, it is a synthetic equivalent of 'Marker degradation' affording an efficient synthesis of C17-OH rockogenin acetate.