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Algae are described as a source of bioactive compounds, with nutritional and therapeutic benefits for the human health [1]. In general, dried macroalgae are foods with a low-caloric content, being rich in non-digestible polysaccharides, proteins and essential aminoacids, vitamins, interesting minerals and phenolic compounds. Although the lipid content is low, this matrix is rich in polyunsaturated fatty acids, essential for the correct functioning of the organism [2]. This study aimed to evaluate the bioactive potential of the hydroethanolic extract of several macroalgae species, namely Laminaria ochroleuca Bachelot de la Pylaie, Saccharina latissila Linnaeus, Ulva lactuca Linnaeus, Palmaria palmata L., Porphyra sp., Codium tomentosum Stackhouse, Undaria pinnafitida (Harvey) Suringar and Himantalia elongate (Linnaeus) SF Grey. The antioxidant activity was evaluated through the OxHLIA method; the antimicrobial activity was determined using the microdilution method using Gram-positive and Gram-negative bacteria, and fungi; and the toxicity was evaluated in a non-tumour primary cell culture (PLP2), by applying the sulforhodamine B assay. The results showed bioactive activity in all the in vitro assays performed. In the antioxidant activity, L. ochroleuca was the species that stood out with an EC50 value of 1.7±0.3 mg/mL. Otherwise, for the antibacterial activity all macroalgae revealed inhibitory capacity against the studied strains, especially S. latissila and H. elongata with MIC values of 0.5 mg/mL for the Salmonella Typhimurium and Bacillus cereus strains, respectively. H. elongata also presented the most promising values for the bactericidal capacity (MBC=1 mg/mL) for Bacillus cereus. Regarding the antifungal activity, inhibitory and fungicidal capacity was also verified in all the studied species, particularly in S. latissila with MIC values of 0.5 mg/mL and MFC values of 1 mg/mL for Aspergillus fumigatus, Aspergillus niger and Aspergillus versicolor strains. Moreover, all the studied macroalgae samples did not present toxicity in the non-tumour primary cell culture evaluated. This work allowed to verify the in vitro bioactive effects of several macroalgae species, namely regarding its antioxidant, antibacterial and antifungal potential. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020); L. Barros, C. Pereira and R. Calhelha thank the national funds through the FCT, I.P., through the institutional scientific employment program-contract for their contracts; and for financial support to Ministry of Education, Science and Technological Development of Republic of Serbia. The authors are also grateful to FEDER-Interreg España-Portugal programme for financial support through the project 0377_Iberphenol_6_E. info:eu-repo/semantics/publishedVersion

Seaweed plays an important role in the biosphere being responsible for most of the production in aquatic ecosystems [1]. Although commonly consumed since ancient times in Asia, their consumption has been increasing in Europe and North America [2]. These species are known for their excellent nutritional value, especially as a protein sources and low lipid and caloric content. In addition, they are rich in several bioactive compounds, such as vitamins, essential fatty acids and phenolic compounds, providing important health benefits to consumers [3]. This work aims to determine ash, proteins, fat, carbohydrates and energy contents, as also the composition in free sugars, organic acids and fatty acids of some seaweeds species, namely Himanthalia elongate L., S.F. Gray; Laminaria ochroleuca Bach.Pyl.; Saccharina latissima L.; Porphyra sp. C.Agardh; Palmaria palmata (L.) Kuntze, and Undaria pinnatifida (Harvey) Suringar. The nutritional aspects were determined using official methodologies for food analysis, while free sugars were identified by HPLC-RI, organic acids by UPFLC-PDA and fatty acids by GC-FID. Proteins stood out as the main macronutrients present, with values that oscillated between 6 and 30 g/100 g of dry weight (dw) for S. latissima and Porphyra sp., respectively. On the other hand, a low lipid content was evident in all the studied seaweed species with values below 1 g/100 g dw, as well as low carbohydrates’ content. The energy values ranged from 218 and 370 kcal/100 g dw for L. ochrouleuca and Porphyra sp, respectively. Furthermore, several compounds of interest were identified, namely free sugars and organic acids, in this case being oxalic acid the only molecule present in all species. Saturated, unsaturated and polyunsaturated fatty acids were also determined, showing a clear heterogeneity of concentrations depending on the species. The present study demonstrates the high potential of these seaweed species as an alternative source of non-animal protein, as well as some molecules with bioactive properties. Thus, the incorporation of this food into the daily diet will contribute for the improvement of a number of functionalities. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2019). L. Barros thanks FCT, P.I., through the institutional scientific employment program-contract for her contract; research contract of C. Caleja (Project AllNatt, POCI- 01-0145-FEDER-030463). The authors are also grateful to Ministerio de Ciencia, Innovación y Universidades for Anxo Carreira-Casais FPU grant; and to Xunta de Galicia for Paula García-Oliveira predoctoral grant info:eu-repo/semantics/publishedVersion

En la actualidad, existe una tendencia en el consumo de alimentos más nutritivos y que aporten beneficios para la salud [1]. En este contexto, el consumo de plantas ha demostrado ser beneficioso, debido a la presencia de diversos nutrientes y moléculas bioactivas con propiedades funcionales. Los polifenoles son un grupo de compuestos que, según diversos estudios, han demostrado propiedades antioxidantes, anti-inflamatorias, antimicrobianas y antitumorales, entre otros, ejerciendo efectos terapéuticos sobre diversas enfermedades [1,2]. Así en el presente trabajo se determinó el perfil individual de compuestos fenólicos en los extractos hidroetanólicos e infusiones obtenidas a partir de las flores de Calluna vulgaris (L.); así como las propiedades bioactivas a través de ensayos in vitro de actividad antioxidante y antimicrobiana. Los compuestos fenólicos individuales se analizaron mediante HPLC-DAD-ESI/MS. La actividad antioxidante se evaluó a través de las metodologías de TBARS y OxHLIA; la actividad antimicrobiana se determinó usando el método de microdilución en bacterias Gram-positivas y Gram-negativas, y en hongos; y finalmente, la hepatotoxicidad se estimó usando un cultivo de células primarias no tumorales (PLP2) y aplicando el ensayo de sulforhodamina B. En la evaluación del perfil fenólico individual, en ambos extractos evaluados (hidroetanólico e infusión) fue evidente la presencia de 20 compuestos fenólicos, de los cuales siete fueron identificados como ácidos fenólicos y trece como flavonoides. La quercetina-3-O-ramnosida se destacó como el compuesto principal. Con respecto a la actividad antioxidante, ambos ensayos testados mostraron valores promisorios de EC50, que tradujeron el excelente potencial antioxidante de la especie. Lo mismo sucedió con la actividad antimicrobiana, donde se demostró el potencial bacteriostático, bactericida y fungicida contra las cepas de bacterias y hongos analizados. También fue probado la ausencia de toxicidad del estrato hidroetanólico y la infusión de C. vulgaris. Este estudio concluyó que C. vulgaris es una flor rica en moléculas bioactivas, especialmente flavonoides y ácidos fenólicos, que pueden generar un gran interés en la industria alimentaria y farmacéutica. Los autores agradecen a la FCT, Portugal y FEDER bajo el Programa PT2020 por el apoyo financiero a CIMO (UID/AGR/00690/2019). L. Barros agradece a FCT, P.I., a través del contrato institucional del programa científico de empleo; contrato de investigación de C. Caleja (proyecto AllNatt, POCI- 01-0145-FEDER-030463); y a lo Programa FEDER-Interreg España-Portugal pelo apoyo financiero a través del proyecto 0377_Iberphenol_6_E. Agradecen tambien al Ministerio de Ciencia, Innovación y Universidades por el soporte económico del investigador pre-doctoral Anxo Carreira Casais y a la Xunta de Galicia “Programa de axudas á etapa predoutoral da Xunta de Galicia” por el apoyo financiero a la investigadora pre-doctoral Paula García Oliveira. A la Xunta de Galicia por el soporte financiero de las “Axudas Conecta Peme” al proyecto IN852A 2018/58 NeuroFood. info:eu-repo/semantics/publishedVersion

Platinum–gold heteronanostructures comprising either dimer (Pt–Au) or core–satellite (Pt@Au) configurations with high catalytic efficiency for ethanol oxidation were synthesized., Platinum–gold heteronanostructures comprising either dimer (Pt–Au) or core–satellite (Pt@Au) configurations were synthesized by means of a seeded growth procedure using platinum nanodendrites as seeds. Careful control of the reduction kinetics of the gold precursor can be used to direct the nucleation and growth of gold nanoparticles on either one or multiple surface sites simultaneously, leading to the formation of either dimers or core–satellite nanoparticles, respectively, in high yields. Characterization by electron tomography and high resolution electron microscopy provided a better understanding of the actual three-dimensional particle morphology, as well as the Au–Pt interface, revealing quasi-epitaxial growth of Au on Pt. The prepared Pt–Au bimetallic nanostructures are highly efficient catalysts for ethanol oxidation in alkaline solution, showing accurate selectivity, high sensitivity, and improved efficiency by generating higher current densities than their monometallic counterparts.

Surface plasmon modes in metallic nanostructures largely determine their optoelectronic properties. Such plasmon modes can be manipulated by changing the morphology of the nanoparticles or by bringing plasmonic nanoparticle building blocks close to each other within organized assemblies. We report the EELS mapping of such plasmon modes in pure Ag nanocubes, Au@Ag coreshell nanocubes, and arrays of Au@Ag nanocubes. We show that these arrays enable the creation of interesting plasmonic structures starting from elementary building blocks. Special attention will be dedicated to the plasmon modes in a triangular array formed by three nanocubes. Because of hybridization, a combination of such nanotriangles is shown to provide an antenna effect, resulting in strong electrical field enhancement at the narrow gap between the nanotriangles.

Detection technologies employing optically encoded particles have gained much interest toward clinical diagnostics and drug discovery, but the portfolio of available systems is still limited. The fabrication and characterization of highly stable surface-enhanced resonance Raman scattering (SERRS)-encoded colloids for the identification and imaging of proteins expressed in cells are reported. These plasmonic nanostructures are made of gold octahedra coated with poly(N-isopropylacrylamide) microgels and can be readily encoded with Raman active dyes while retaining high colloidal stability in biofluids. A layer-by-layer polyelectrolyte coating is used to seal the outer surface of the encoded particles and to provide a reactive surface for covalent conjugation with antibodies. The targeted multiplexing capabilities of the SERRS tags are demonstrated by the simultaneous detection and imaging of three tumor-associated surface biomarkers: epidermal growth factor receptor (EGFR), epithelial cell adhesion molecule (EpCAM), and homing cell adhesion molecule (CD44) by SERRS spectroscopy. The plasmonic microgels are able to discriminate tumor A431 (EGFR+/EpCAM+/CD44+) and nontumor 3T3 2.2 (EGFR−/EpCAM−/CD44+) cells while cocultured in vitro.