Abstract：
:Caffeic acid, rosmarinic acid and oligomers of caffeic acid with multiple catechol groups are all constituents of Salvia officinalis. Their antioxidant potential was investigated with regard to their radical scavenging activity and the stability and structure of the intermediate radicals. Pulse-radiolytic studies revealed very high rate constants with hydroxyl radicals. Evidence from kinetic modeling calculations suggested an unusual complex behavior due to the presence of both O4- and O3-semiquinones and formation and decay of a hydroxyl radical adduct at the vinyl side chain. The radical structures observed by EPR spectroscopy after autoxidation in slightly alkaline solutions were only partially identified due to their instability and generally represented dissociated O4-semiquinones. Hybrid density-functional calculations of the potential radical structures showed distinct differences between the resonance stabilization of the O4- and O3-semiquinones of caffeic and dihydrocaffeic acids, reflected also in the considerably faster decay of the O3-semiquinone observed by pulse radiolysis. No evidence was found for dimerization reactions via Cbeta radicals typical for lignin biosynthesis.
journal_name
Biol Resjournal_title
Biological researchauthors
Bors W,Michel C,Stettmaier K,Lu Y,Foo LYdoi
10.4067/s0716-97602004000200017keywords:
subject
Has Abstractpub_date
2004-01-01 00:00:00pages
301-11issue
2eissn
0716-9760issn
0717-6287journal_volume
37pub_type
杂志文章abstract：:Duchenne muscular dystrophy (DMD) is secondary to loss-of-function mutations in the dystrophin gene. The causes underlying the progression of DMD, differential muscle involvement, and the discrepancies in phenotypes among species with the same genetic defect are not understood. The mdx mouse, an animal model with dyst...
journal_title：Biological research
pub_type： 杂志文章,评审
doi：10.4067/s0716-97602005000400010
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journal_title：Biological research
pub_type： 杂志文章
doi：/S0716-97602009000200003
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abstract：BACKGROUND:Despite manifold benefits of nanoparticles (NPs), less information on the risks of NPs to human health and environment has been studied. Cobalt oxide nanoparticles (Co3O4-NPs) have been reported to cause toxicity in several organisms. In this study, we have investigated the role of Co3O4-NPs in inducing phyt...
journal_title：Biological research
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doi：10.1186/s40659-016-0080-9
更新日期：2016-03-18 00:00:00
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journal_title：Biological research
pub_type： 杂志文章,评审
doi：
更新日期：1993-01-01 00:00:00
abstract：:The purpose of this study was to carry out a bibliometric analysis of the articles published in Chile during 1987-2006 that were categorized into the Plant Science discipline by ISI. The data was extracted from the Web of Science datábase, obtaining a total of 911 articles for analysis. Almost half of the articles wer...
journal_title：Biological research
pub_type： 杂志文章
doi：/S0716-97602008000200002
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journal_title：Biological research
pub_type： 杂志文章
doi：10.1186/s40659-016-0086-3
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journal_title：Biological research
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doi：/S0716-97602010000400008
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journal_title：Biological research
pub_type： 杂志文章
doi：/S0716-97602009000100003
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journal_title：Biological research
pub_type： 杂志文章
doi：/S0716-97602011000200009
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journal_title：Biological research
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journal_title：Biological research
pub_type： 杂志文章
doi：
更新日期：1995-01-01 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
doi：
更新日期：1994-01-01 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
doi：10.1186/s40659-016-0089-0
更新日期：2016-06-03 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
doi：10.4067/s0716-97602001000300010
更新日期：2001-01-01 00:00:00
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journal_title：Biological research
pub_type： 杂志文章,评审
doi：10.1186/0717-6287-47-66
更新日期：2014-12-10 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
doi：10.4067/s0716-97602003000300009
更新日期：2003-01-01 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
doi：10.4067/s0716-97602002000300012
更新日期：2002-01-01 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
doi：
更新日期：1998-01-01 00:00:00
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journal_title：Biological research
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doi：/S0716-97602009000400006
更新日期：2009-01-01 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
doi：/S0716-97602008000300004
更新日期：2008-01-01 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
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journal_title：Biological research
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doi：/S0716-97602008000100004
更新日期：2008-01-01 00:00:00
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journal_title：Biological research
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更新日期：2015-09-12 00:00:00
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journal_title：Biological research
pub_type： 杂志文章
doi：10.1186/0717-6287-47-9
更新日期：2014-04-01 00:00:00
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journal_title：Biological research
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journal_title：Biological research
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journal_title：Biological research
pub_type： 杂志文章
doi：/S0716-97602011000400008
更新日期：2011-01-01 00:00:00
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journal_title：Biological research
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doi：/S0716-97602010000200013
更新日期：2010-01-01 00:00:00
abstract：:Skeletal muscles have the potential to regenerate by activation of quiescent satellite cells, however, the molecular signature that governs satellite cells during muscle regeneration is not well defined. Myosin light chains (Myls) are sarcomere-related proteins as traditional regulator of muscle contraction. In this r...
journal_title：Biological research
pub_type： 杂志文章
doi：/S0716-97602009000100013
更新日期：2009-01-01 00:00:00
