Pyrolysis liquids from coal are complex mixtures of organic compounds with low to high molecular mass and low to high polarity. Compared to low-molecular-weight compounds, little information is available regarding high-molecular-weight compounds in pyrolysis liquids, although their characterization is important for the elucidation of degradation pathways. In this study, laser desorption ionization (LDI) using graphite powder as the support material has been used in conjunction with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) for the analysis of a pyrolysis liquid from brown coal. The acquired data is compared to previous results of the same sample using electrospray ionization (ESI). Using LDI, compounds with masses between 300 and 900 Da were detected by LDI. An evaluation of the spectra was based on the frequency of molecular formulas with a different number of heteroatoms. Hydrocarbon compounds and heteroatomic compounds containing oxygen and sulfur were found. A comparison to ESI results shows that the numbers of observed molecular formulas are virtually the same, but a higher quantity of molecular formulas with a low number of oxygen can be detected by LDI. The observation of molecular formulas without oxygen is a unique feature of the LDI spectra. A more detailed investigation was possible by the utilization of double bond equivalent plots versus carbon number, which revealed a prevalence of LDI for the ionization of compounds with higher DBE.

(1) The nutritional quality of strawberry (Fragaria × ananassa Duch) fruits, among others, is largely maintained by the presence of soluble sugars and organic acids. As the primary products of photosynthesis, they are energy depots in plants, necessary for the construction of cell constituents, but also serve as precursors of aromatic compounds and signaling molecules. (2) In this study, fruits of 25 strawberry cultivars were qualitatively and quantitatively characterized concerning individual sugars and organic acids by HPLC, FT-ICR-MS, and MS imaging analysis. In addition, the total quality index (TQI), as a novel mathematical model, was used to compare all individual parameters evaluated to obtain a quantitative single score, as an indicator of overall fruit quality. (3) Regardless of a large number of cultivars and monitored parameters that were studded, several cultivars stood out in terms of selected primary metabolites, such as ‘Rumba’, ‘Jeny’, and ‘Sandra’, while the latter had the best TQI score. (4) Intercultivar variations in sugars and organic acids profiles, along with other bioactive compounds, should be considered for selection of promising cultivars with improved naturally occurring nutraceutical traits. Besides the search for a pleasant taste, increased awareness of healthy nutrition resulted in heightening consumer demand for high-quality fruit.

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