The autoxidation of unsaturated lipids in micelles. Synergism of inhibitors vitamins C and E

Author:

Barclay Lawrence Ross Coates,Locke Steven Jeffrey,MacNeil Joseph Mark

Abstract

The kinetics of thermally (30 °C) initiated autoxidations of unsaturated lipids, linoleic acid, and methyl linoleate are studied in 0.50 M sodium dodecyl sulfate (SDS) micelles. The rate of chain initiation, R1, was controlled by using known amounts of the thermal initiator, di-tert-butylhyponitrite (DBHN). The initiator efficiency, e, determined by the induction period method with x-tocopherol, was 0.30 for linoleic acid and varied (0.30 to 0.36) for methyl linoleate autoxiation as the concentration of the ester increased. The rate of autoxidation of linoleic acid follows the classical rate law since it is proportional to the substrate concentration and to the square root of chain initiation. The oxidizability of linoleic acid measured in micelles is 4.09 × 10−2 M−1/2 s−1/2. The oxidizability of methyl linoleate varied from 2.37 × 10−2 to 6.92 × 10−2 M−1/2 s−1/2 as the amount of solubilized ester increased. The latter results are indicative of pooling of the ester in the micellar phase. Additions of aqueous solutions of ascorbic acid to α-tocopherol-inhibited micellar autoxidations result in very significant extensions of the efficient inhibition period compared to that obtained with α-tocopherol alone. The mechanism of this synergism is briefly discussed.

Publisher

Canadian Science Publishing

Subject

Organic Chemistry,General Chemistry,Catalysis

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3