Musterbildung und Selbstorganisation epicuticularer Wachskristalle auf pflanzlichen Oberflächen
Zusammenfassung der Projektergebnisse
Plant epicuticular waxes are the outermost boundary layer of most of the land plants. Based on their micro morphology and chemical composition waxes form multifunctional surfaces. Although their appearance is documented well, much less is known about their formation processes. In the first three years of this project, the self-assembly process of different plant waxes has been studied on plant and technical surfaces. The fourth year of the project focused on more special, open questions in wax tubule formation, as the influence of the different wax components on the building of wax tubules. The influence of the alkanediols on the building process of the nonacosanol tubules was determined. Therefore, natural waxes were separated into compound fractions by flash column chromatography and a new procedure for the synthesis of pure nonacosan-10-ol was developed (Dommisse et al. in review). Recrystallisation experiments with these fractions and mixtures of them showed that pure nonacosanol does not build tubular crystals. However, if alkanediols are added to the solution, proportional more tubules were built. The minimum amount of alkanediols necessary for the building of tubular crystals was experimentally determined to be 2 to 3 percent by weight. These amounts of alkanediols are also available in the epicuticular waxes of the used plant species (Tropaeolum majus). Because nonacosan-10-ol is a chiral molecule, it exists in two enantiomeric forms and it is known from literature that the natural nonacosanol tubules exist out of (S)-nonacosan-10-ol. However, during the synthesis of (S)-nonacosan-10-ol also the other enantiomer (R)-nonacosan-10-ol was synthesised (Dommisse et al. in review). Recrystallisation experiments with this enantiomer showed that pure (R)-nonacosanol also does not build tubules. Because of the configuration of the natural alkanediols, which is supposed to be (S), their admixture to the (R)-nonacosanol did not yield any tubules.
Projektbezogene Publikationen (Auswahl)
- Koch, K., Dommisse, A., Koch, S. and Barthlott, W. (2005) Biomimetic Hydrophobic Surfaces generated by self-assembly of plant waxes, XVII International Botanical Congress, Vienna, Austria, July 17th - 23rd.
- Hommes, A., Koch, K., Broekmann, P., Barthlott, W. and Wandelt, K. (2006) Modelling of epicuticular wax layers: Self-assembly of octacosan-1-ol on artificial surfaces, International conference on nanoscience and technology, Basel, Switzerland, July 30 - August 4.
- Koch, K., Barthlott, W., Koch, S., Hommes, A., Wandelt, K., Mamdouh, W., De Feyter, S. and Broekmann, P. (2006) Structural analysis of wheat wax (Triticum aestivum, c.v. 'Naturastar' L.): from the molecular level to three dimensional crystals, Planta 223, 258-270.
- Koch, K., Dommisse, A., Hommes, A., Broekmann, P., Wandelt, K., Barthlott, W. and Gorb, S.N. (2006) Plant waxes as templates for microstructured biomimetic surfaces, International conference on nanoscience and technology 2006, Basel, Switzerland, July 30 - August 4.
- Bargel, H., Koch, K., Cerman, Z. and Neinhuis, C. (2006) Structure-function relationships of the plant cuticle and cuticular waxes - a smart material?, Functional Plant Biology 33, Evans Review 3, 893-910.
- Dommisse, A., Barthlott, W., Wandelt, K., Broekmann, P., Hommes, A. and Koch, K. (2005) Biomimetic hydrophobic surfaces by self-assembly of plant waxes, European Conference on Surface Science 23, Berlin, Germany, September 4th - 9th.
- Dommisse, A., Koch, K., Neinhuis, C. and Barthlott W. (2004) Self-repairing systems of waxes on living plant surfaces, Scanning Probe Microscopies and Organic Materials XIII, Bielefeld, Germany, July 6th - 8th.
- Ensikat, H.-J., Boese, M., Mader, W., Barthlott, W. and Koch, K. (2006) Crystallinity of plant epicuticular waxes: Electron and X-ray diffraction studies, Chemistry and Physics of Lipids 144, 45-59.
- Hommes, A., Koch, S., Dommisse, A., De Feyter, S., Koch, K., Broekmann, P., Barthlott, W. and Wandelt, K. (2005) Model studies on the growth of epicuticular wax layers: AFM, STM and SEM investigations, European Conference on Surface Science 23, Berlin, Germany, September 4th - 9th.
- Koch, K. (2006). Selbstorganisation und molekulare Architektur epikutikularer Wachse: Intergration mikroskopischer, chemischer und kristallographischer Analysen Habilitation Thesis, Nees-Institut for Biodiversity of Plants, University of Bonn (Germany).
- Koch, K. and Dommisse, A. (2005) Funktionen und Regeneration epikutikularer Wachse, 13. Tagung Arbeitskreis Blattdüngung des VCI, Frankfurt am Main, Germany, October 13th.
- Koch, K., Dommisse, A. and Barthlott, W. (2006) Chemistry and crystal growth of wax tubules from Lotus (Nelumbo nucifera) and Nasturtium (Tropaeolum majus) leaves on technical substrates, Crystal Growth and Design 6, 2571-2578.
- Koch, K., Dommisse, A., Neinhuis, C. and Barthlott W. (2003) Self-assembly of epicuticular waxes on living plant surfaces by atomic force microscopy, 12th International conference on scanning tunnelling microscopy/spectroscopy and related techniques, Eindhoven, The Netherlands, July 21st - 25th.
- Koch, K., Dommisse, A., Neinhuis, C. and Barthlott, W. (2003) Regeneration of epicuticular waxes of Thalictrum flavum observed by atomic force microscopy, Scanning Probe Microscopies and Organic Materials XII, Mainz, Germany, September 24th - 26th.
- Koch, K., Dommisse, A., Neinhuis, C. and Barthlott, W. (2003) Self-assembly of epicuticular waxes on living plant surfaces by atomic force microscopy in Scanning Tunneling Microscopy/Spectroscopy and Related Techniques by Koenraad, P. M. and Kemerink, M., American Institute of Physics, Melville (NY, USA), 457-460.
- Koch, K., Neinhuis, C., Ensikat, H.-J. and Barthlott, W. (2004) Self assembly of epicuticular waxes on living plant surfaces imaged by atomic force microscopy (AFM), Journal of Experimental Botany 55, 711-718.
