Skin aging is a biological process influenced by intrinsic and extrinsic factors. The last ones, mainly exposure to UV radiation, increases reactive oxygen species (ROS) production leading to a loss of extracellular matrix, also enhanced by enzymatic degradation of matrix supporting molecules. Thus, and with the growing demand for eco-friendly skin products, natural compounds extracted from brown seaweeds revealed to be good candidates due to their broad range of bioactivities, especially as antioxidants. The aim of this study was to assess the dermo-cosmetic potential of different fractions obtained from the brown seaweed Fucus spiralis. For this purpose, in vitro antioxidant (Total Phenolic Content (TPC), 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, Ferric Reducing Antioxidant Power (FRAP), Oxygen Radical Absorbance Capacity (ORAC)), anti-enzymatic (collagenase, elastase and hyaluronidase), antimicrobial, anti-inflammatory (NO production) and photoprotective (ROS production) capacities were evaluated. Although nearly all fractions evidenced antioxidant effects, fraction F10 demonstrated the highest antioxidant ability (EC₅₀ of 38.5 µg/mL, DPPH assay), and exhibited a strong effect as an inhibitor of collagenase (0.037 µg/mL) and elastase (3.0 µg/mL). Moreover, this fraction was also the most potent on reducing ROS production promoted by H₂O₂ (IC₅₀ of 41.3 µg/mL) and by UVB (IC₅₀ of 31.3 µg/mL). These bioactivities can be attributed to its high content of phlorotannins, as evaluated by LC-MS analysis, reinforcing the potential of F. spiralis for further dermatological applications.

Inflammation is a double-edged sword, as it can have both protective effects and harmful consequences, which, combined with oxidative stress (OS), can lead to the development of deathly chronic inflammatory conditions. Over the years, research has evidenced the potential of marine sponges as a source of effective anti-inflammatory therapeutic agents. Within this framework, the purpose of this study was to evaluate the antioxidant and the anti-inflammatory potential of the marine sponge Cliona celata. For this purpose, their organic extracts (C1–C5) and fractions were evaluated concerning their radical scavenging activity through 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and anti-inflammatory activity through a (lipopolysaccharides (LPS)-induced inflammation on RAW 264.7 cells) model. Compounds present in the two most active fractions (F5 and F13) of C4 were tentatively identified by gas chromatography coupled to mass spectrometry (GC-MS). Even though samples displayed low antioxidant activity, they presented a high anti-inflammatory capacity in the studied cellular inflammatory model when compared to the anti-inflammatory standard, dexamethasone. GC-MS analysis led to the identification of n-hexadecanoic acid, cis-9-hexadecenal, and 13-octadecenal in fraction F5, while two major compounds, octadecanoic acid and cholesterol, were identified in fraction F13. The developed studies demonstrated the high anti-inflammatory activity of the marine sponge C. celata extracts and fractions, highlighting its potential for further therapeutic applications.

As the world hurtles toward its urban future, there is a growing need to reduce solid wastes, like organic, plastic, and paper residues as these are recurring by-products of our intensive consumer-based economic lifestyle. Poorly managed waste has a colossal impact on health, environment and economy [1,2], therefore a main concern is the recycling of waste materials using environmental friendly techniques like bioconversion. The bioconversion of organic based waste, such as paper residues, into soluble sugars (e.g. glucose) can be achieved through an enzymatically catalysed reaction [2,3] Algae represent a set of natural resources with a wide spectrum of compelling compounds, broadly used in various areas, such as food, agriculture, pharmaceuticals, cosmetics and feed. Ulva lactuca is an edible highly nutritious green algae (Chlorophyceae) rich in vitamins (e.g. thiamin, biotin, β-carotene, etc.) and fibers (57%). In addition, this specie has the advantage of having its life cycle well studied and a high production in aquaculture [4,5]. In this research, we evaluated the growth potential and cellulase production in Cellulomonas sp. using Ulva lactuca as carbon source. The growth of Cellulomonas sp., was performed for 168 hours at 30°C, with 24 hours samplings, in M9 Culture Medium (M9CM) sample tubes under different conditions: (a) [Algae]=1.16mg.mL-1; (b) [Algae]=1.16mg.mL-1 without thiamin and biotin; (c) [Algae]=2.24mg.mL-1. The results showed a better growth for samples supplemented with algae, especially in (c). The same pattern was observed in the paper degradation assay, where samples (c) showed an average concentration of soluble sugars (SS) per weight of carboard samples of 0.0124 [SS].mg-1. Assays performed with the commercial enzyme (Celluclast®) showed an average concentration of 0.427 [SS].mg-1 for similar samples. Seaweeds present promising applications as carbon sources due to their high content in fibers and proteins, while future studies could be performed exploring the potential of mainly invasive algae species.

The production of organisms in aquaculture systems has been increasing exponentially in the last years as to prevent overexploitation of marine resources, a consequence of a massive growth of the global population numbers and rise in consumption of fish protein. Although aquaculture industry allows a faster production of selected organisms, a major problem, faced constantly, is the exposure of individuals to chronical stress and pathogenic organisms, factors responsible for high economical failures in the sector. Most of these pathogens belong to the Vibrionaceae family, which are fought by the extensive use of chemicals and antibiotics, therefore creating more resistant strains while leading to increasing levels of pollution, trough organic matter discharges into the marine environment [1-4]. Considerable investments have been made to discover new compounds with compelling properties, with a major part of the research made, focusing on the use of marine probiotics. These are marine microorganisms, fungi or bacteria, that when consumed benefit the health of the host organism, namely being able of inhibiting the activity of some pathogenic agents [1,2]. Several studies have successfully shown the interesting properties of probiotics obtained from different species of fish. Sparus aurata (Linnaeus, 1758), most commonly known as gilthead seabream, can be found abundantly on the Atlantic shore and is intensively grown in aquaculture systems. The constant exposure of these individuals to a wide range of pathogens, promotes the development of defence mechanisms [1,2]. This study evaluates the antimicrobial activity of the intestinal microbiota of S. aurata against Vibrio alginolyticus, Vibrio harveyi and Vibrio anguillarum, using the Disk-Diffusion method. For this purpose, the intestinal content of gilthead seabream, obtained from the marine environment, was suspended in NaCl solution (1.5%). Bacterial suspensions (100 μL) were spread in Tryptic Soy Agar (TSA) culture medium supplemented with NaCl (1.5%) (VWR) and in selective culture medium Thiosulfate-Citrate-Bile Salts-Sucrose (TCBS agar, VWR). Plates were incubated at 37°C and 30°C, respectively. After an incubation period of 92 hours, 20 colonies with distinct morphology were selected. These were collected and pure colonies were isolated. Colonies were grown in the liquid media previously indicated and placed in a shaking incubator (IKA, Germany). Cells were lysed through sonication, followed by centrifugation for 10 minutes, full speed. The resulting lysates were stored at -20°C. In order to test the pathogen exclusion competence, samples were then added to Mueller-Hinton plates containing one of the three pathogenic agents in study, along with a negative control and a positive control disk (chloramphenicol, 30μg/mL, Oxoid). After incubation for 24 hours the inhibition of pathogen growth wasn’t registered for none of the Vibrio strains. Even though the intestinal microbiota of Sparus aurata didn’t trigger an inhibitory effect on the growth of the pathogenic organisms, more research should be made on this subject, using a more extensive range of pathogenic organisms and samples sources.