The plant kingdom has evolved an enormous number of chemically diverse metabolites that protect plants from biotic and abiotic stresses. The large number of metabolites in a given plant indicates... Show moreThe plant kingdom has evolved an enormous number of chemically diverse metabolites that protect plants from biotic and abiotic stresses. The large number of metabolites in a given plant indicates interactions between metabolites are very likely. The co-occurrence of plant metabolites comprise a natural background where these metabolites have to function and this is often overlooked or ignored in ecological studies. The main goal of this thesis is to understand the importance of metabolite interactions I used assays with a generalist herbivore to study the interactions between chlorogenic acid (CGA), pyrrolizidine alkaloids (PAs) and fractions from Jacobaea plants. I found that PA free bases, PA N-oxides (the oxidized form of free base) and CGA decreased thrips survival. Although PA free bases and CGA decreased thrips survival, the combination of the two toxins was less toxic than the single toxins. In contrast, the combination of PA N-oxides with CGA enhanced the toxicity against thrips in a synergistic way. Adding PAs to different plant fractions showed that metabolite interactions on thrips survival are common as in all tested combinations we found antagonistic and synergistic effects. Clearly, bioactivity of a metabolite is strongly dependent upon the co-occurrence of metabolites in the plant cell. Show less
Lanthanoid coordination polymers (Ln CPs), self-assembled from organic ligands and lanthanoid ions, combine the promising properties of normal transition metal CPs, such as a well-defined... Show moreLanthanoid coordination polymers (Ln CPs), self-assembled from organic ligands and lanthanoid ions, combine the promising properties of normal transition metal CPs, such as a well-defined structures and large surface areas, with the properties of lanthanoid ions, notably luminescence and magnetism. As the oxidation state and chemical properties of the lanthanoid ions are highly similar, it is possible to prepare mixed-metal Ln CPs which show dual emission from two different lanthanoid ions or lanthanoid ions and ligands. In this research we focused on the preparation of Ln CPs, especially those containing two or more different lanthanoid ions, and the exploration of their applications in sensing. These dual-emission Ln CPs show good performance for temperature sensing: the intensity ratio from two individual emission peaks can be used as parameters for temperature. Furthermore, Gd2O3 was demonstrated to be an excellent substrate for the growth of thin films of Ln CPs. The temperature-sensing properties of these Ln CP films are also reported. Show less
