Zonal Changes in Ascorbate and Hydrogen Peroxide Contents, Peroxidase, and Ascorbate-Related Enzyme Activities in Onion Roots
نویسندگان
چکیده
منابع مشابه
Zonal changes in ascorbate and hydrogen peroxide contents, peroxidase, and ascorbate-related enzyme activities in onion roots.
Onion (Allium cepa) roots growing hydroponically show differential zonal values for intra- (symplastic) and extra- (apoplastic) cellular ascorbate (ASC) and dehydroascorbate (DHA) contents and for related enzyme activities. In whole roots, ASC and DHA concentrations were higher in root apex and meristem and gradually decreased toward the root base. Guaiacol peroxidase, ASC peroxidase, monodehyd...
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Ascorbate (ascorbic acid, vitamin C), in pharmacologic concentrations easily achieved in humans by i.v. administration, selectively kills some cancer cells but not normal cells. We proposed that pharmacologic ascorbate is a prodrug for preferential steady-state formation of ascorbate radical (Asc(*-)) and H(2)O(2) in the extracellular space compared with blood. Here we test this hypothesis in v...
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ROS detoxification is an essential process in protecting plant cells and their organelles, which is caused by ROS generated in stress condition. Peroxidase (POD) isozyme, Malondialdehyde (MDA) content, and Ascorbate peroxidase (APX) activity are the indicators of plants for measuring pollution effects. The purpose of the present study was to investigate Cd-induced stress on POD isozymes, MDA co...
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The activity of ascorbate peroxidase (APX) has been studied with H(2)O(2) and various reducing substrates. The activity decreased in the order pyrogallol>ascorbate>guaiacol>2, 2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS). The inactivation of APX with H(2)O(2) as the sole substrate was studied. The number of H(2)O(2) molecules required for maximal inactivation of the enzyme was d...
متن کاملSecondary Metabolite Contents and Antioxidant Enzyme Activities of Cichorium intybus Hairy Roots in Response to Zinc
Hairy root systems are formed by transforming plant tissues with the “natural genetic engineer” Agrobacterium rhizogenes. In most plants such as Cichorium intybus L., hairy root cultures have proven to be an efficient system for secondary metabolites production. The effect of Zinc (ZnSO4), a heavy metal, was investigated at different concentrations (0, 1, 5 and 10 mM) on some secondary metaboli...
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ژورنال
عنوان ژورنال: Plant Physiology
سال: 2003
ISSN: 0032-0889,1532-2548
DOI: 10.1104/pp.012682