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The development of alga-based biodegradable membranes represents a significant advancement in fuel cell technology, aligning with the need for sustainable material solutions. In a significant advancement for sustainable energy technologies, we have developed a novel biodegradable κ-carrageenan (KC) and boron nitride (BN) nanoparticle membrane, optimized with ammonium sulfate (NHS). This study employed a set of characterization techniques, including thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), where thermal anomalies were observed in the membranes around 160 °C and 300 °C as products of chemical decomposition. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) revealed the phases corresponding to the different precursors, whose value in the EDS measurements reached a maximum in the KC/BN/NHS5% membrane at 2.31 keV. In terms of the mechanical properties (MPs), a maximum tensile stress value of 10.96 MPa was achieved for the KC/BN sample. Using Fourier transform infrared spectroscopy (FTIR), the physicochemical properties of the membranes were evaluated. Our findings reveal that the KC/BN/NHS1% membrane achieves an exceptional ionic conductivity of 7.82 × 10−5 S/cm, as determined by impedance spectroscopy (IS). The properties of the developed membrane composite suggest possible broader applications in areas such as sensor technology, water purification, and ecologically responsive packaging. This underscores the role of nanotechnology in enhancing the functional versatility and sustainability of energy materials, propelling the development of green technology solutions. 

Microalgae peptides have many medical and industrial applications due to their functional properties. However, the rapid degradation of peptides not naturally present in biological samples represents a challenge. A strategy to increase microalgae peptide stability in biological samples is to use carriers to protect the active peptide and regulate its release. This study explores the use of gold nanoparticles (AuNPs) as carriers of the Chlorella microalgae peptide (VECYGPNRPQF). The potential of these peptide biomolecules as stabilizing agents to improve the colloidal stability of AuNPs in physiological environments is also discussed. Spectroscopic (UV-VIS, DLS) and Microscopic (TEM) analyses confirmed that the employed modification method produced spherical AuNPs by an average 15 nm diameter. Successful peptide capping of AuNPs was confirmed with TEM images and FTIR spectroscopy. The stability of the microalgae peptide increased when immobilized into the AuNPs surface, as confirmed by the observed thermal shifts in DSC and high zeta-potential values in the colloidal solution. By optimizing the synthesis of AuNPs and tracking the conferred chemical properties as AuNPs were modified with the peptide via various alternative methods, the synthesis of an effective peptide-based coating system for AuNPs and drug carriers was achieved. The microalgae peptide AuNPs showed lower ecotoxicity and better viability than the regular AuNPs. 

Worsening environmental conditions due to climate change have profoundly affected the health of coral reefs worldwide. Thus, understanding how corals respond to fluctuating and/or extreme levels of temperature and solar irradiation will guide future protection and restoration efforts of this valuable ecosystem. Herein, we present a study of the immune responses of the endangered coralAcropora cervicornisto seasonal fluctuations in water temperature (WT), light intensity (LI), and water depth. Immune responses were observed by measuring the concentration of green and cyan fluorescent proteins (GFP and CyFP) and the activity of phenoloxidase (PO), an enzyme involved in the biosynthesis of the photoprotective protein melanin. To study these responses, visually healthyA. cervicornisfragments were placed at 8, and 12 m depth, and GFP, CyPF, and PO activity were measured at three-month intervals over a 12-month period. Seawater temperature and light intensity were also measured at each depth during this period. A general linear mixed model was used to determine the effects of seasonal variations of WT, LI, and water depth on the immune proteins. GFP, CyFP, and PO activity varied significantly across time – all higher in late summer/early fall and lower in late winter/early spring. Likewise, WT and LI significantly affected GFP, CyFP, and PO activity. On the other hand, water depth only had a significant effect on fluorescent protein concentrations but not PO activity. Our study demonstrates that corals can modulate these key immune-related proteins throughout natural seasonal fluctuations. That is, increasing in months of higher thermal and light conditions while decreasing in months with mild thermal and light conditions. The phenotypic plasticity ofA. cervicornisin adapting to a changing environment underscores the importance that in future studies time of the year should be a meaningful consideration when evaluating the responses ofA. cervicornisto the environment.