Lemna minor L. as a model organism for ecotoxicological studies performing 1H NMR fingerprinting

A validated method applying 1H NMR fingerprinting for the study of metabolic changes caused in Lemnaminor L. by various phytotoxic substances is presented. 1H NMR spectra of crude extracts from untreated and treated colonies with the herbicides glyphosate, mesotrione, norflurazon, paraquat and the phytotoxin pyrenophorol were subjected to multivariate analyses for detecting differences between groups of treatments. Partial least squares-discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA) were carried out in order to discriminate and classify treatments according to the observed changes in the metabolome of the plant. Although the compounds at the concentrations used did not cause macroscopically observable symptoms of phytotoxicity, characteristic metabolic changes were detectable by analyzing 1H NMR spectra. Analyses results revealed that metabonomics applying 1H NMR fingerprinting is a potential method for the investigation of toxicological effects of xenobiotics on L. minor, and possibly on other duckweed species, helping in the understanding of such interactions.