Metal ion-inducing metabolite accumulation in Brassica rapa

• Published in: Journal of plant physiology 2008-09, Vol.165 (14), p.1429-1437
• Main Authors: Jahangir, Muhammad, Abdel-Farid, Ibrahim Bayoumi, Choi, Young Hae, Verpoorte, Robert
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Brassica rapa; Brassica rapa - drug effects; Brassica rapa - metabolism; Discriminant Analysis; Fundamental and applied biological sciences. Psychology; Ions; Least-Squares Analysis; Magnetic Resonance Spectroscopy; Metabolome - drug effects; Metabolomic analysis; Metal ions; Metals - toxicity; NMR spectroscopy; Partial least square-discriminant analysis; Plant Leaves - drug effects; Plant Leaves - metabolism; Plant physiology and development; Plant Roots - drug effects; Plant Roots - metabolism; Principal Component Analysis
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/j.jplph.2008.04.011

Plants face a number of biotic and abiotic environmental stress factors during growth. Among the abiotic factors, in particular, a great deal of attention has been paid to metals not only because of their increasing amounts in the environment due to rapid industrial development but also because of the variation of metal composition in soil. Cultivation of crops close to industrial areas or irrigation with contaminated water may result in both growth inhibition and tissue accumulation of metals. Brassica species are well known as metal accumulators and are being used for phytoremediation of contaminated soils. However, the metal tolerance mechanism in the plant still remains unclear. In order to investigate the metabolomic changes induced by metal ions in Brassica, plants were subjected to concentrations 50, 100, 250 and 500 mmol of copper (Cu), iron (Fe) and manganese (Mn) in separate treatments. 1H NMR and two-dimensional NMR spectra coupled with principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) were applied to investigate the metabolic change in Brassica rapa (var. Raapstelen). The 1H-NMR analysis followed by the application of chemometric methods revealed a number of metabolic consequences. Among the metabolites that showed variation, glucosinolates and hydroxycinnamic acids conjugated with malates were found to be the discriminating metabolites as were primary metabolites like carbohydrates and amino acids. This study shows that the effects of Cu and Fe on plant metabolism were larger than those of Mn and that the metabolomic changes varied not only according to the type of metal but also according to its concentration.