|
Title
|
|
|
|
Oxidative stress in plants : EPR monitoring in DMPO-DMSO based extracts
| |
|
Author
|
|
|
|
| |
|
Abstract
|
|
|
|
| Oxygen derived radicals were measured in Brassica napus hypocotyl segments by means of EPR (electron paramagnetic resonance) after spin-trapping with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) in a dimethylsulfoxide(DMSO)-based medium. Next to the ascorbyl radical signal, an EPR signal due to DMPO-CH3, generated by reaction of free OH radicals with DMPO, was detected. The DMPO-CH3 signals were quantified in Brassica napus hypocotyl segments at different times after wounding and in vitro culture. A maximum was detected as a function of time after wounding. When hypocotyl segments were kept in the dark, a reduction of about 70% of both the DMPO-CH3 and ascorbyl line intensity in comparison to the light control was observed. This suggests that the production of ascorbyl. and hydroxyl radicals is associated with photooxidative stress. Only small traces of: DMPO-OOH (superoxide) were detected in Brassica hypocotyl segments. In contrast, in DMPO-DMSO based extracts of Arabidopsis seedlings sprayed with diquat (0.1 %), superoxide radicals were detected as adducts of DMPO. Consequently, the non-detection of DMPO-OOH in leaves of untreated Arabidopsis seedlings and the very weak signals detected in Brassica napus hypocotyls are clearly related to the absence or the very small amounts of superoxide in both tissues. |
| |
|
Language
|
|
|
|
English
| |
|
Source (journal)
|
|
|
|
Journal of plant physiology. - Jena, 1984, currens
| |
|
Publication
|
|
|
|
Jena
:
1999
| |
|
ISSN
|
|
|
|
0176-1617
[print]
1618-1328
[online]
| |
|
DOI
|
|
|
|
10.1016/S0176-1617(99)80329-0
| |
|
Volume/pages
|
|
|
|
154
:1
(1999)
, p. 132-136
| |
|
ISI
|
|
|
|
000078280200019
| |
|
Full text (Publisher's DOI)
|
|
|
|
| |
|