Enhancing Bioproducts in Seaweeds via Sustainable Aquaculture: Antioxidant and Sun-Protection Compounds

Marine macroalgae are considered an untapped source of healthy natural metabolites and their market demand is rapidly increasing. Intertidal macroalgae present chemical defense mechanisms that enable them to thrive under changing environmental conditions. These intracellular chemicals include compounds that can be used for human benefit. The aim of this study was to test cultivation protocols that direct seaweed metabolic responses to enhance the production of target antioxidant and photoprotective biomaterials. We present an original integrated multi-trophic aquaculture (IMTA) design, based on a two-phase cultivation plan, in which three seaweed species were initially fed by fish effluents, and subsequently exposed to various abiotic stresses, namely, high irradiance, nutrient starvation, and high salinity. The combined effect of the IMTA’s high nutrient concentrations and/or followed by the abiotic stressors enhanced the seaweeds’ content of mycosporine-like amino acids (MAAs) by 2.3-fold, phenolic compounds by 1.4-fold, and their antioxidant capacity by 1.8-fold. The Sun Protection Factor (SPF) rose by 2.7-fold, and the chlorophyll and phycobiliprotein synthesis was stimulated dramatically by an order of magnitude. Our integrated cultivation system design offers a sustainable approach, with the potential to be adopted by emerging industries for food and health applicationsPartial funding for open access charge: Universidad de Málag

Polyaniline-coated single-walled carbon nanotubes: synthesis, characterization and impact on primary immune cells

Functionalized carbon nanotubes are increasingly exploited as innovative components for the development of advanced biomedical devices. In this study we report a novel synthetic route for the formation of single-walled carbon nanotube (SWCNT)\u2013polyaniline (PANI) hybrids by in situ chemical polymerization. The surfactant sodium dodecylsulfate (SDS) is used as a template for monomer assembly and polymerization. The resulting composite preserves the surfactant and is characterized by a tight binding between SWCNTs and PANI. Having the idea of integrating these new types of SWCNT conjugates into advanced biomedical tools (i.e. implantable multi-electrode arrays), we explored their potential impact on the viability and function of cells from the immune system. We have compared the cytotoxic effects of SWCNT-COOH, SWCNT/SDS and SWCNT/SDS/PANI on mouse spleen cells and macrophages. The results indicate that biocompatibility of the different SWCNT conjugates is dependent both on the doses used and the type of cells