The number of cancer-related diseases is still growing. Despite the availability of a large number of anticancer drugs, the ideal drug is still being sought that would be effective, selective, and overcome the effect of multidrug resistance. Therefore, researchers are still looking for ways to improve the properties of already-used chemotherapeutics. One of the possibilities is the development of targeted therapies. The use of prodrugs that release the bioactive substance only under the influence of factors characteristic of the tumor microenvironment makes it possible to deliver the drug precisely to the cancer cells. Obtaining such compounds is possible by coupling a therapeutic agent with a ligand targeting receptors, to which the attached ligand shows affinity and is overexpressed in cancer cells. Another way is to encapsulate the drug in a carrier that is stable in physiological conditions and sensitive to conditions of the tumor microenvironment. Such a carrier can be directed by attaching to it a ligand recognized by receptors typical of tumor cells. Sugars seem to be ideal ligands for obtaining prodrugs targeted at receptors overexpressed in cancer cells. They can also be ligands modifying polymers’ drug carriers. Furthermore, polysaccharides can act as selective nanocarriers for numerous chemotherapeutics. The proof of this thesis is the huge number of papers devoted to their use for modification or targeted transport of anticancer compounds. In this work, selected examples of broad-defined sugars application for improving the properties of both already-used drugs and substances exhibiting anticancer activity are presented.

Reducing waste production and improving waste treatment are key objectives in the EU’s Circular Economy Action Plan. Anaerobic digestion of food waste is a promising method, but safely disposing of its by-products, which contain valuable nutrients like nitrogen, phosphorus, and organic matter, remains a challenge. These nutrients suggest potential use in agriculture to enhance sustainability, yet their effects on plant growth need thorough understanding. This study investigated the impact of liquid digestates from anaerobic digestion of food waste, combined with fish sludge (from recirculated aquaculture systems), on plant growth (Lepidium sativum and Triticum aestivum) through direct soil tests. The content of biogenic elements in the digestates did not differ and was 0.32% for N, <0.05% for P, and 0.15% for K. Two tests were conducted, both using artificial soil prepared to OECD 207 standards: the Phytotoxkit™ test (ISO 18763:2016) and a pot experiment (OECD 208). Results showed that digestates initially delayed germination and hindered early plant growth, an effect that diminished over time. This may be due to the high organic matter content of digestates, similar to standard fertilizers like manure or compost. Pre-incubating digestates in soil before application, similar to common agricultural practices with soil amendments, is suggested as a potential solution.

The rapid expansion in the production and application of carbon nanomaterials (CNMs) raises increasing concerns regarding their environmental fate and ecological safety. Herein, we present a systematic cross-trophic assessment of fourteen well-characterized 0D–3D CNMs, including fullerene soot (FS), fullerene C60, amino-acid-derived carbon quantum dots (CQDs), single- and multi-walled carbon nanotubes (SWCNTs, MWCNTs), graphene (G1 and G3) materials, graphite (GR), and nanodiamonds (ND). Acute and chronic ecotoxicity was evaluated across three aquatic trophic levels representing producers (Lemna minor), consumers (Daphnia magna), and decomposers (Aliivibrio fischeri), following OECD and ISO guidelines. Toxic responses were strongly dependent on both trophic level and physicochemical properties of CNMs. D. magna exhibited the highest sensitivity, particularly toward long, carboxylated (oxidized) MWCNTs (MWCNT-COOH) (EC50(48 h) = 5.8 mg L–1), where toxicity was associated with digestive tract accumulation and physical interference. In contrast, L. minor was most affected by leucine-derived CQDs (EC50 = 65.2 mg L–1), inducing chlorosis and growth inhibition. The bacterial model showed generally lower sensitivity, with toxicity modulated by dispersion behaviour and surface characteristics. Across CNMs, no single parameter governed hazard; rather, toxicity emerged from the interplay of dimensionality, aspect ratio, dispersibility, and surface chemistry with organism-specific exposure pathways. These findings highlight the necessity of integrated, multi-trophic ecotoxicological evaluation for carbon nanomaterials and identify high-aspect-ratio, environmentally dispersible nanotubes as priority candidates for environmental risk assessment.