Linked Life Data

19096100

Source:http://linkedlifedata.com/resource/pubmed/id/19096100

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-4
pubmed:dateCreated
2008-12-19
pubmed:abstractText
Detailed kinetic studies have been performed for the reaction of aroxyl (ArO.) radical with vitamin E (alpha-, beta-, gamma-, delta-tocopherol, TocH), ubiquinol-10, and related antioxidants in micellar solution, using a stopped-flow spectrophotometer. The second-order reaction rates (ks) obtained increased in the order of hydroquinone < tocol<delta-TocH<ubiquinol-0<gamma-TocH-beta-TocH<ubiquinol-10<alpha-TocH at pH 4-8. The antioxidants which have lower oxidation potentials (Ep) showed higher reactivities. The reaction rates obtained in micellar solution were pH dependent because of the dissociation of OH groups in the antioxidants. For instance, by comparing the ks values with the mole fraction of each molecular form of ubiquinol-10, the reaction rate ks1 (1.21 x 10(5) M(-1)s(-1)) for undissociated form, ks2 (1.04 x 10(6) M(-1)s(-1)) for monoanion and ks3 (0 M(-1)s(-1)) for dianion, and the pKa1 and pKa2 values (11.4 and 12.7) were determined. It was found that the relative ratio of ks values (100:21:20:2.9) of alpha-, beta-, gamma-, delta-tocopherols in micellar dispersion has good correlation with the relative biological activities for rat fetal resorption, rat haemolysis, and chicken muscle dystrophy. The relative antioxidant activities of alpha-tocopherol and ubiquinol-10 have been discussed on the basis of the products of the ks values and their concentrations in serum and several tissues (heart, muscle, liver, kidney, and brain).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0951-6433
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
49-58
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Comparison between the free-radical-scavenging activities with vitamin E and ubiquinol in biological systems based on their reaction rates: a research account.
pubmed:affiliation
Department of Chemistry, Faculty of Science, Ehime University, Matsuyama, Japan. mukai@chem.sci.ehime-u.ac.jp
pubmed:publicationType
Journal Article, Comparative Study