High blood cholesterol levels are one of the main risks for atherosclerotic disease. A purified aqueous extract of Fucus vesiculosus, characterized as rich in phlorotannins and peptides, was described as having the capacity to inhibit cholesterol biosynthesis and intestinal absorption. In this work, the effect of this extract on intestinal cells metabolites and proteins was analysed, aiming to expand the knowledge about its mode of action targeting cholesterol metabolism, in particular exogenous cholesterol absorption and transport. Caco-2 cells differentiated into enterocytes were exposed to the purified aqueous extract of F. vesiculosus and analysed by undirected metabolomics and proteomics. The results of the metabolomic analysis showed only statistically significant differences in glutathione content of the cells exposed to the extract relatively to the control cells, with a decreased glutathione expression in exposed cells. The proteomic analysis showed an increased expression for cells exposed to the extract of NPC1, an important protein known to be involved in cholesterol transport. To extent of our knowledge this is the first study using untargeted metabolomics and proteomic analysis to study the effect of F. vesiculosus on differentiated Caco-2 cells, which aims to provide some insight about the molecular mechanism of extract compounds on intestinal cells.

A brown seaweed consumed worldwide, Fucus vesiculosus, has been used to prevent atherosclerosis and hypercholesterolemia, among other uses, however, the mechanisms of action that lead to these effects are not yet fully understood. An F. vesiculosus aqueous extract, prepared as a soup was characterized as rich in sev-eral bioactive compounds, mainly phlorotannin and peptides. This work aims to study the in vitro effect of this extract on the expression of different proteins involved in the synthesis and transport of cholesterol in HepG2 cells, though a proteomic analysis, western blot and qRT-PCR. The results demonstrated that, in liver cells, the extract decreases the expression of 4 proteins involved in cholesterol biosynthesis process and also decrease the expression of two important transporters proteins of cholesterol, NPC1L1 and ABCG5, as well as decrease the NPC1L1 mRNA levels. Our study demonstrates some mechanisms of action of bioactive com-pounds from F. vesiculosus that may explain its previously reported hypocholesterolemic effect.

This study focuses on the development and characterization of a series of six new dansyl derivatives (L1 to L6) and their integration into PMMA polymers for application in environmental sensing. The photophysical properties of these derivatives were extensively studied in various solvents and in solid state. A remarkable positive solvatochromic effect was observed, indicating their potential in microenvironmental polarity assessment. The dansyl derivatives demonstrated selective sensing capabilities for Cu2+ and Hg2+ metal ions, with the formation of mononuclear species. Additionally, their acid-base responsive nature was explored, revealing potential for pH-sensitive applications. The incorporation of these derivatives into PMMA polymers resulted in acid-base sensitive materials suitable for environmental monitoring, particularly in detecting hazardous gases and changes in pH levels. This integration overcomes the solubility limitations of dansyl compounds and extends their applicability in diverse sensing scenarios.

The lectin found in the tubers of the Winter Aconite (Eranthis hyemalis) plant (EHL) is a Type II Ribosome Inactivating Protein (RIP); type II RIPs have shown anti-cancer properties, and have great potential as therapeutic agents. Similarly, colloidal gold nanoparticles are successfully used in biomedical applications as gold nanoparticles can be functionalised with ligands with high affinity and specificity for target cells to create therapeutic and imaging agents. Herein we present the synthesis and characterization of gold nanoparticles conjugated with EHL. The aim was to establish the viability of the conjugate and perform a set of initial assays to establish whether the biological effect of EHL is altered by the conjugation. The biological assays were performed in Caenorhabditis elegans, a free living nematode commonly used for toxicological studies; previous work from some of the authors using first life stage (L1) nematodes has shown that EHL has a strong biocidal effect on C. elegans. Gold nanoparticles functionalised with EHL (AuNPs@EHL) were successfully synthesised by bioconjugation with citrate gold nanoparticles (AuNPs@Citrate); the conjugates were analysed by UV-Vis spectroscopy, Dynamic Light Scattering (DLS), Zeta Potential analysis and Transmission Electron Microscopy (TEM). Results indicate that an optimal functionalisation was achieved with the addition of 100 µL of EHL (concentration 1090 ± 40 µg/mL) over 5 mL of AuNPs (concentration [Au0] = 0.8 mM). Biological assays on the effect of AuNPs@EHL on C. elegans were performed, using first life stage (L1) and pre-adult stage (L4) nematodes. Citrate gold nanoparticles did not have any obvious effect on the nematodes. For L1 stage nematodes, the assays show that conjugation with gold nanoparticles reduced the biological effect of EHL on C. elegans. As lectin binding activity is essential for the natural protein to bind and allow entry to cells, conformational changes due to conjugation may have affected this binding affinity. For L4 stage nematodes, both EHL alone and AuNPs@EHL showed biological activity, and reproductive delays and reduced fecundity were observed in both cases. These assays indicate that EHL can be conjugated to gold nanoparticles and retain elements of biocidal activity.