Detection and quantification of unbound phytochelatin 2 in plant extracts of Brassica napus grown with different levels of mercury.
The mercury (Hg) accumulation mechanism was studied in rape (Brassica napus) plants grown under a Hg concentration gradient (0 microm-1,000 microm). Hg mainly accumulated in roots. Therefore, the presence of phytochelatins (PCs) was studied in the roots of the plants. The high stability of the PC-Hg multicomplexes (mPC-nHg) seems to be the main reason for the lack of previous Hg-PC characterization studies. We propose a modification of the method to detect and quantify unbound PC of Hg in plant extracts via high-performance liquid chromatography coupled to electrospray tandem mass spectrometry and inductively coupled plasma mass spectrometry in parallel. We separated the PC from the Hg by adding the chelating agent sodium 2,3-dimercaptopropanesulfonate monohydrate. We only detected the presence of PC after the addition of the chelating agent. Some multicomplexes mPC-nHg could be formed but, due to their large sizes, could not be detected. In this study, only PC(2) was observed in plant samples. Hg accumulation was correlated with PC(2) concentration (r(2) = 0.98).
Iglesia-Turiño
Santiago
S
Departament de Biologia Vegetal, Facultat de Biologia , University of Barcelona, 08028 Barcelona, Spain.
Febrero
Anna
A
Jauregui
Olga
O
Caldelas
Cristina
C
Araus
Jose Luis
JL
Bort
Jordi
J
D029688:Brassica napus / Q000187:drug effects* / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005978:Glutathione / Q000032:analysis / Q000378:metabolism*; D008628:Mercury / Q000494:pharmacology*; D054811:Phytochelatins; D010936:Plant Extracts / Q000737:chemistry*; D018517:Plant Roots / Q000378:metabolism
D010936:Plant Extracts; D054811:Phytochelatins; D008628:Mercury; D005978:Glutathione