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Aluminium capsules can be used as the final packaging for any type of powdered foods, such as tea or vitamin and similar hot drinks. Aluminium represents a 100% barrier, is impermeable, extends the shelf life of the final product, is recyclable and an alternative to plastic. A wide range of individualized products, including the capsule as attractive single-use possibility, made it possible to satisfy the preferences and expectations of consumers. Currently two main materials for single serve portion coffee capsules are in use: aluminium and/or plastic based.

Bisphenol A (BPA) presents a serious threat to soil ecosystems, yet its effects on soil- inhabiting organisms are mostly unexplored. Therefore, the impact of environmentally relevant BPA concentrations on a terrestrial model organism, the earthworm Eisenia fetida, was assessed. Animals were cutaneously exposed to 100 nM and 10 μM BPA up to 10 days (10-d). Next, a battery of biomarkers was used for ecotoxicological evaluation on a cellular, tissue and behavioural level. HPLC analysis showed that after a 10-d exposure, BPA accumulation reached a maximum of 2.50 μg BPA per g of wet tissue weight. On the cellular level, up to 3-d BPA exposure caused increased lipid oxidation indicating oxidative stress. Histopathological assessment of cell wall and ovaries after 7- and 10-d BPA exposure showed multiple abnormalities, i.e. hyperplasia of epidermis, increased body wall thickness and ovarian atrophy. Detection of these changes was facilitated by a newly proposed semi- quantitative scoring system. Finally, behavioural changes were detected after only 3 days of exposure to 100 nM BPA. Altogether, the presented multilevel toxicity evaluation indicates high sensitivity of earthworms to low BPA doses.

In this study we examined the role of multidrug efflux transport in differential accumulation and potency of inorganic (HgCl2) and organic (CH3HgCl) mercury in sea urchin (Strongylocentrotus purpuratus) embryos. To quantify mercury toxicity we assessed the effect of HgCl2 and CH3HgCl on cell division. Our assay detects the incidence of interference with progression through the first cell cycle, which occurs primarily through the effects of mercury on spindles (microtubules) in metaphase and anaphase. We found that the EC50 concentrations for interference with mitosis are 610 nM for HgCl2 and 124 nM for CH3HgCl. Pharmacological inhibition of MRP/ABCC-type multidrug efflux activity significantly increases the anti-mitotic potency of inorganic mercury, but has virtually no effect on the potency of organic mercury - partial inhibition of the MRP mediated efflux activity with 5 µM MK571, a model inhibitor of MRP efflux transporters, increased the toxicity of HgCl2 2.8-fold. Similarly, inhibition of these transporters increased intracellular accumulation of HgCl2 but has no effect on accumulation on CH3HgCl – 5 µM MK571 caused 2-fold and 20 µM MK571 caused 4-fold increase in intracellular mercury accumulation. Our results point to the MRP mediated efflux transport as an important biological determinant of mercury accumulation and subsequent toxic potency in aquatic organisms.

Disulfide bonds (SS-bonds) are important posttranslational modifications of proteins. They stabilize a three-dimensional (3D) structure (structural SS-bonds) and have also the catalytic or regulatory functions (redox-active SS-bonds). Although SS-bonds are present in all groups of organisms, no comparative analyses of their frequency in proteins from different domains of life have been made to date. Using the Protein Data Bank (PDB), the number and subcellular locations of SS-bonds in Archaea, Bacteria, and Eukarya have been compared. Approximately three times higher frequency of proteins with SS-bonds in eukaryotic secretory organelles (e.g. endoplasmic reticulum) than in bacterial periplasmic/secretory pathways was calculated. Protein length also affects the SS-bond frequency: the average number of SS-bonds is positively correlated with the length for longer proteins (> 200 amino acids) while for the shorter and less stable proteins (< 200 amino acids) this correlation is negative. Medium size proteins (250 - 350 amino acids) indicated a high number of SS-bonds only in Archaea that could be explained by the need for additional protein stabilization in hyperthermophiles. The results emphasize higher capacity for the SS-bond formation and isomerization in Eukarya when compared to Archaea and Bacteria.

Multixenobiotic resistance (MXR) mechanism is present in many organisms as an important cellular detoxification mechanism and is mediated by the activity of ATP binding cassette (ABC) transporters that bind and actively efflux different toxic substrates out of the cell. Here we present data on molecular identification of ABC efflux transporter - P-glycoprotein (P-gp/Abcb1), as a representative of MXR phenotype, in soil organism - earthworm *Eisenia fetida*. Partial cDNA sequence of *Abcb1 * was identified and its overall identity with ABCB1 homologues of other organisms ranged from 58.5 to 72.5 %. Furthermore we looked at the impact of five modulators (verapamil, cyclosporin A, MK571, probenecid, orthovanadate) to the earthworm’s MXR mechanism activity. To confirm MXR reversion by these agents, we measured in *E. fetida* the accumulation of model substrates rhodamine B and rhodamine 123 in whole body tissue of the adult earthworm. The results showed that MK571, OV and VER modulators significantly inhibit MXR transport activity in experiment performed on filter paper contact test. Our data for the first time evidence the presence of P-gp/Abcb1 related gene in earthworm "E. fetida". In addition, we have demonstrated the importance of MXR as the specific detoxification mechanism that helps earthworms to survive in polluted environments.