1. Localization, ligand environment, bioavailability and toxicity of mercury in Boletus spp. and Scutiger pes-caprae mushroomsAnja Kavčič, Klemen Mikuš, Marta Debeljak, Johannes Teun van Elteren, Iztok Arčon, Alojz Kodre, Peter Kump, Andreas-Germanos Karydas, Alessandro Migliori, Mateusz Czyzycki, Katarina Vogel-Mikuš, 2019, original scientific article Abstract: This study provides information on mercury (Hg) localization, speciation and ligand environment in edible mushrooms: Boletus edulis, B. aereus and Scutiger pes-caprae collected at non-polluted and Hg polluted sites, by LA-ICP-MS, SR-μ-XRF and Hg L3-edge XANES and EXAFS. Mushrooms (especially young ones) collected at Hg polluted sites can contain more than 100 μg Hg g−1 of dry mass. Imaging of the element distribution shows that Hg accumulates mainly in the spore-forming part (hymenium) of the cap. Removal of hymenium before consumption can eliminate more than 50% of accumulated Hg.
Mercury is mainly coordinated to di-thiols (43–82%), followed by di-selenols (13–35%) and tetra-thiols (12–20%). Mercury bioavailability, as determined by feeding the mushrooms to Spanish slugs (known metal bioindicators owing to accumulation of metals in their digestive gland), ranged from 4% (S. pes-caprae) to 30% (B. aereus), and decreased with increasing selenium (Se) levels in the mushrooms. Elevated Hg levels in mushrooms fed to the slugs induced toxic effects, but these effects were counteracted with increasing Se concentrations in the mushrooms, pointing to a protective role of Se against Hg toxicity through HgSe complexation. Nevertheless, consumption of the studied mushroom species from Hg polluted sites should be avoided. Keywords: edible mushrooms, HgSe complex, imaging of elemental distribution, LA-ICP-MS, alpha-XRF, XAS Published in RUNG: 24.10.2019; Views: 5188; Downloads: 0 This document has many files! More... |
2. Recent advances in 2D imaging of element distribution in Plants by focused beam techniquesKatarina Vogel-Mikuš, Johannes Teun van Elteren, Marjana Regvar, Jitrin Chaiprapa, Boštjan Jenčič, Iztok Arčon, Alojz Kodre, Peter Kump, Anja Kavčič, Mitja Kelemen, Dino Metarapi, Marijan Nečemer, Primož Vavpetič, Primož Pelicon, Paula Pongrac, 2019, independent scientific component part or a chapter in a monograph Keywords: 2D Imiging, XRF, XANES, synchrotron light Published in RUNG: 05.09.2019; Views: 3920; Downloads: 0 This document has many files! More... |
3. X-ray spectrometry in plant biologyKatarina Vogel-Mikuš, Iztok Arčon, Alojz Kodre, Anja Kavčič, Peter Kump, Primož Pelicon, 2018, published scientific conference contribution abstract (invited lecture) Abstract: Trace elements are essential components of living systems, but at the same time they can be toxic at concentrations beyond those necessary for their biological functions. In addition, the toxicity can be extended to other non-essential elements of very similar atomic characteristics that can mimic the properties of a trace element.
Trace element malnutrition affects more than half of the world’s population, while on the other hand industrialization, traffic and extensive use of fertilizers have resulted in exceedingly high concentrations of non-essential elements in food crops, posing risks to human health.
In order to be able to develop and improve phyto-technologies that enable production of safe and quality food, knowledge on the basic mechanisms involved in trace and non-essential element uptake, transport, accumulation and ligand environment in plants is needed.
Such studies are nowadays supported by highly sophisticated X-ray based techniques, such as synchrotron based X-ray fluorescence spectrometry, proton induced X-ray emission and X-ray absorption spectroscopy, enabling imaging of element distribution and determination of speciation and ligand environment of trace elements in biological tissues and cells with high spatial resolution and sensitivity.
Selected case studies of metal distribution and speciation in selected model and crop plants, achieved by interdisciplinary work, will be presented. Keywords: X-ray spectrometry, plants, XANES, EXAFS Published in RUNG: 12.09.2018; Views: 4146; Downloads: 0 This document has many files! More... |
4. Isotopic and elemental characterisation of Slovenian apple juice according to geographical origin: Preliminary results : /Karmen Bizjak Bat, Klemen Eler, Darja Mazej, Branka Mozetič Vodopivec, Ines Mulič, Peter Kump, Nives Ogrinc, 2016, original scientific article Abstract: This study examined the applicability of stable isotope and multi-element data for determining the geographical
origin of fresh apple juices. Samples included three apple cultivars (Idared, Golden Delicious
and Topaz) harvested in 2011 and 2012 from five different geographical regions of Slovenia. Regional discrimination
of the juice samples was most successful when using linear discriminant analysis (LDA) and
taking into account the following parameters: d2H and d18O content of juice water; d15N and d13C content
of the pulp, (D/H)I and (D/H)II in ethanol and the concentration of S, Cl, Fe, Cu, Zn and Sr. Overall prediction
ability was 83.9%. The factors that best distinguished the different types of cultivar were the d2H and
d18O content of fruit juice water; the d13C and (D/H)I content of ethanol; and the concentration of S, Mg, K,
Cu, and Ti. Prediction ability, taking into account all ten parameters, was 75.8%. Keywords: Apple juice, Stable isotopes, Elemental content, Geographical origin, Slovenia Published in RUNG: 15.02.2016; Views: 6746; Downloads: 0 This document has many files! More... |