Analytical Methods to Characterize the Composition of Surface Lipids of Helophytes Exposed to Contaminated Water

Abstract

The epidermis of plants is coated by a thin cuticular membrane protecting the plant from water loss and UV radiation. This lipid layer includes long-chained fatty acids, esters, hydrocarbons, alcohols, aldehydes and ketones. The composition of these compounds depends on the species, their ages and growing conditions. Also chemical stress seems to change the qualitative and quantitative composition of the lipid layers caused by pollutant interfered plants biosynthesis. Particularly the chain length, saturation and branching of fatty acids change during pollutant exposure as previous studies indicated. In this project especially the wax layer of juncus effusus and phragmitis communis were studied under chemical stress caused by chlorobenzene and hydrocarbon contaminated water. The extractable surface lipids were isolated from the plants and analyzed by gas chromatography-mass spectrometry after derivatization. For data processing a pattern recognition program was used that based on a costume made data base containing typical plant lipid substances. First results indicate that in comparison to the control plants the composition and particularly the amount of the wax components changed clearly in the exposed plants. Statistical evaluation of the data confirmed the alterations determined as significant influence of the pollutants.