Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2004-4-23
pubmed:abstractText
The rate constants, k(inh), for reaction of stilbazulenyl-bis-nitrone (STAZN, 1) with peroxyl radicals and the number of radicals trapped, n, are compared with those of phenolic antioxidants 2,2,5,7,8-pentamethyl-6-hydroxychroman (PMHC, 4a), 2,5,7,8-tetramethyl-6-hydroxychroman-2-carboxylic acid (Trolox, 4b), and 2,6-di-tert-butyl-4-methoxyphenol (DBHA, 5). The behavior of STAZN depended markedly on the media and type of initiator used, water-soluble or lipid-soluble. In styrene/chlorobenzene and initiation by azo-bis(isobutyronitrile) (AIBN), k(inh) (STAZN) = 0.64 k(inh) (5) = 0.02k(inh) (4a). On addition of methanol, the k(inh) of STAZN increased 6-fold to be four times that of 5 while that of 4a decreased 6-fold. In aqueous SDS-micelles containing methyl linoleate and initiation with water-soluble azo-bis(amidinopropane)2HCl, ABAP, the relative k(inh) values were 1 >or= 4b > 5. In dilinoleoylphosphatidyl choline (DLPC) bilayers and initiation with lipid-soluble azo-bis-2,4(dimethylvaleronitrile) (DMVN), the k(inh) order was 5 > 4b > 1. During initiation with ABAP in micelles and bilayers, the calculated values of k(inh) for STAZN changed during the induction period. The experimental results are interpreted in terms of the conformation of STAZN, which is transoid in homogeneous solution but cisoid in aqueous dispersions of lipids. In such dispersions, the STAZN lies at the lipid-water interface where it traps water-soluble peroxyl radicals by a single electron-transfer mechanism. The cisoid conformation at lipid-water interfaces is supported by theoretical calculations.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Antioxidants, http://linkedlifedata.com/resource/pubmed/chemical/Free Radicals, http://linkedlifedata.com/resource/pubmed/chemical/Linoleic Acids, http://linkedlifedata.com/resource/pubmed/chemical/Lipid Bilayers, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Lipids, http://linkedlifedata.com/resource/pubmed/chemical/Micelles, http://linkedlifedata.com/resource/pubmed/chemical/Nitriles, http://linkedlifedata.com/resource/pubmed/chemical/Nitrogen Oxides, http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylcholines, http://linkedlifedata.com/resource/pubmed/chemical/Sesquiterpenes, http://linkedlifedata.com/resource/pubmed/chemical/Solutions, http://linkedlifedata.com/resource/pubmed/chemical/Water, http://linkedlifedata.com/resource/pubmed/chemical/isobutyronitrile, http://linkedlifedata.com/resource/pubmed/chemical/methyl linoleate, http://linkedlifedata.com/resource/pubmed/chemical/stilbazulenyl nitrone
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-3263
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
69
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2929-36
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Kinetic studies on stilbazulenyl-bis-nitrone (STAZN), a nonphenolic chain-breaking antioxidant in solution, micelles, and lipid membranes.
pubmed:affiliation
Contribution from the Departments of Chemistry, Mount Allison University, Sackville, NB, E4L 1G8 Canada.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't