Linked Life Data

16203143

Source:http://linkedlifedata.com/resource/pubmed/id/16203143

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
2005-11-1
pubmed:abstractText
The new catecholic xanthone, 1,3,7-trihydroxy-4-(1,1-dimethyl-2-propenyl)-5,6-(2,2-dimethylchromeno)-xanthone (1), was isolated from the root bark of Cudrania tricuspidata together with seven known xanthones. The structures were fully characterized by analysis of physical and spectral (UV, IR, mass, and NMR) data. Relationships between the structural characteristics of xanthones and their antioxidant activities (DPPH, superoxide, and hydroxyl radical) were studied. Among the range of catecholic xanthones, 6,7-dihydroxyl xanthones (3-8) exhibited a strong scavenging effect on the DPPH radical. When one of the catecholic hydroxyl groups was protected as in compounds 1 and 2, DPPH radical scavenging activity was markedly decreased (IC(50)>200microM). DPPH activities were consistent with electrochemical response by cyclic voltammetry. Interestingly, compounds (1, 2) which had the weak activities on DPPH, exhibited both potent superoxide and hydroxyl radical scavenging activities. The strong activity on the hydroxyl radical of compounds (1, 2) could be rationalized by their chelating effect with iron (Fe(2+)) due to a redshift of its complex. The catecholic xanthones (3-8), being able to convert quinone methide intermediate, showed potent cytotoxicities against human cancer cell lines (HT-29, HL-60, SK-OV3, AGS, and A549). In particular, compounds 3, 6, and 7 had strong cytotoxic activities against AGS (LD(50)<5microM). DNA fragmentation patterns induced by catecholic xanthones revealed that tumor cell death was due to apoptosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0960-894X
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5548-52
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Antioxidant and cytotoxic activities of xanthones from Cudrania tricuspidata.
pubmed:affiliation
Department of Agricultural Chemistry, Division of Applied Life Science, Institute of Agriculture & Life Science, Gyeongsang National University, Jinju 660-701, Republic of Korea.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't