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1.
Appl Biochem Biotechnol ; 135(2): 133-44, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17159237

RESUMO

The generation of reactive oxygen species is thought to cause extensive oxidative damage to various biomolecules such as DNA, RNA, and protein. In this study, the preventive, suppressive, and protective effects of in vitro supplementation with electrolyzed-reduced water on H2O2-induced DNA damage in human lymphocytes were examined using a comet assay. Pretreatment, cotreatment, and posttreatment with electrolyzed-reduced water enhanced human lymphocyte resistance to the DNA strand breaks induced by H2O2 in vitro. Moreover, electrolyzed-reduced water was much more effective than diethylpyrocarbonate-treated water in preventing total RNA degradation at 4 and 25 degrees C. In addition, electrolyzed-reduced water completely prevented the oxidative cleavage of horseradish peroxidase, as determined using sodium dodecyl sulfate-polyacrylamide gels. Enhancement of the antioxidant activity of ascorbic acid dissolved in electrolyzed-reduced water was about threefold that of ascorbic acid dissolved in nonelectrolyzed deionized water, as measured by a xanthine-xanthine oxidase superoxide scavenging assay system, suggesting an inhibitory effect of electrolyzedreduced water on the oxidation of ascorbic acid.


Assuntos
DNA/química , Proteínas/química , RNA/química , Água/química , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Eletrólise , Humanos , Peróxido de Hidrogênio/química , Linfócitos/efeitos dos fármacos , Oxirredução
2.
Prep Biochem Biotechnol ; 34(3): 253-64, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15461141

RESUMO

Secretory anionic isoperoxidase (EC 1.11.1.7), named PA1, was 68-fold purified from scented-geranium (Pelargonium graveolense) callus by using ion exchange chromatography and gel filtration. Isoperoxidase PA1 was a glycoprotein with an isoelectric point (pI) of 4.0. The molecular weight of PA1 was approximately 42.5 and 44 kDa, estimated by SDS-PAGE and Sephadex G-150 gel filtration, respectively. The optimum pH of the enzyme was 5.0 for guaiacol and H2O2, and the Km values for guaiacol and H2O2 were 1.96 and 8.5mM, respectively. Substrate studies in terms of optimum pHs and Km values with various synthetic and naturally occurring phenolic compounds were performed. In comparison with cationic isoperoxidase, PC3, which has been already characterized, anionic isoperoxidase PA1 had much lower Km values for synthetic phenolic compounds and much higher Km values for naturally occurring phenolic compounds than PC3. Moreover, anionic isoperoxidase PA1 could utilize ferulic acid as a substrate very well, while cationic isoperoxidase PC3 could not utilize ferulic acid as a substrate.


Assuntos
Pelargonium/enzimologia , Peroxidase/química , Peroxidase/isolamento & purificação , Cromatografia em Gel , Cromatografia por Troca Iônica , Focalização Isoelétrica , Ponto Isoelétrico , Peso Molecular , Pelargonium/citologia
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