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Lake Avernus is a volcanic lake located in southern Italy. Since ancient times, it has inspired numerous myths and legends due to the occurrence of singular phenomena, such as coloring events. Only recently has an explanation been found for them, i.e., the recurring color change over time is due to the alternation of cyanobacterial blooms that are a consequence of natural nutrient inputs as well as pollution resulting from human activities. This current report specifically describes the red coloring event that occurred on Lake Avernus in March 2022, the springtime season in this region of Italy. Our innovative multidisciplinary approach, the Fast Detection Strategy (FDS), was devised to monitor cyanobacterial blooms and their toxins. It integrates remote sensing data from satellites and drones, on-site sampling, and analytical/bioinformatics analyses into a cohesive information flow. Thanks to FDS, we determined that the red color was attributable to a bloom of Planktothrix rubescens, a toxin-producing cyanobacterium. Here, we report the detection and identification of 14 anabenopeptins from this P. rubescens strain, seven of which are known and seven are newly reported herein. Moreover, we explored the mechanisms and causes behind this cyclic phenomenon, confirming cyanobacterias role as reliable indicators of environmental changes. This investigation further validates FDSs effectiveness in detecting and characterizing cyanobacterial blooms and their associated toxins, expanding its potential applications.

Exhausted olive pomace (EOP) represents the principal residue of olive pomace. Several studies have optimized the extraction of specialized metabolites from the EOP of Olea europaea L., but a comparison between different extractive methods has not been made. For this reason, the present investigation aims to compare four different extractive methods by using water and 15% ethanol/water as extractive solvents. Specifically, based on extract antioxidant activity, the methods compared were maceration (MAC), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and Accelerated Solvent Extraction (ASE). Between these, the UAE and ASE hydroalcoholic EOP extracts were demonstrated to have the highest antioxidant activity. Subsequently, these extracts were investigated for their hypoglycemic and antiradical activity using in vitro cell-free and cell-based assays, respectively. ASE hydroalcoholic EOP extract demonstrated the greatest ability to inhibit the α-amylase enzyme and an in vitro antioxidant activity comparable to N-acetyl cysteine in HepG2 cells. UAE and ASE extracts' phytochemical characterization was also performed, identifying seven phenolic compounds, including 3-hydroxytyrosol, tyrosol, and, for the first time, salidroside. The ASE hydroalcoholic EOP extract was the richest from a phytochemical point of view, thus confirming its major biological activity. Therefore, ASE and 15% ethanol/water may represent the best extractive method for EOP nutraceutical valorization. [ABSTRACT FROM AUTHOR]

Introduction: Biofouling poses a significant economic threat to various marine industries, leading to financial losses that can reach billions of euros annually. This study highlights the urgent need for effective alternatives to traditional antifouling agents, particularly following the global ban on organotin compounds. Material and methods: Streptomyces aculeolatus PTM-346 was isolated from sediment samples on the shores of the Madeira Archipelago, Portugal. The crude extract was fractionated using silica flash chromatography and preparative HPLC, resulting in two isolated marinone compounds: madeirone (1), a novel marinone derivative discovered in this study, and neomarinone (2). The antifouling activities of these compounds were tested against five marine bacterial species and the larvae of the mussel Mytilus galloprovincialis. Additionally, in silico and in vivo environmental toxicity evaluations of madeirone (1) and neomarinone (2) were conducted. Results: Madeirone (1) demonstrated significant antibiofilm efficacy, inhibiting Phaeobacter inhibens by up to 66%, Marinobacter hydrocarbonoclasticus by up to 60%, and Cobetia marina by up to 40%. Neomarinone (2) also exhibited substantial antibiofilm activity, with inhibition rates of up to 41% against P. inhibens, 40% against Pseudo-oceanicola batsensis, 56% against M. hydrocarbonoclasticus, 46% against C. marina, and 40% against Micrococcus luteus. The growth inhibition activity at the same concentrations of these compounds remained below 20% for the respective bacteria, highlighting their effectiveness as potent antibiofilm agents without significantly affecting bacterial viability. Additionally, both compounds showed potent effects against the settlement of Mytilus galloprovincialis larvae, with EC50 values of 1.76 μg/mL and 0.12 μg/mL for compounds (1) and (2), respectively, without impairing the viability of the targeted macrofouling species. In silico toxicity predictions and in vivo toxicity assays both support their potential for further development as antifouling agents. Conclusion: The newly discovered metabolite madeirone (1) and neomarinone (2) effectively inhibit both microand macrofouling. This distinct capability sets them apart from existing commercial antifouling agents and positions them as promising candidates for biofouling prevention. Consequently, these compounds represent a viable and environmentally friendly alternative for incorporation into paints, primers, varnishes, and sealants, offering significant advantages over traditional copper-based compounds. [ABSTRACT FROM AUTHOR]

It has been possible to isolate plakoside A and B from the marine sponge Plakortis simplex. These are unique beta-galactosyl-ceramides. Their galactose residues are alkylated at O-2 by a 3,3-dimethylallyl group. The presence of a prenylated galactose in plakosides is extremely important in relation to their biological activity. All the unsubstituted monoglycosylceramides into which research has been undertaken so far have been found to be immunostimulating, regardless of the nature of the sugar and of the alpha or beta stereochemistry of the glycosidic linkage.

The correlation between stressors and bioindicators can provide evidence of environmental status both as an indication and monitoring tool, and in the identification of the pollutant source. Cyanobacteria possess several hallmark traits of good bioindicators: physiological tolerances or ecological ranges of specific cyanobacterial species can differ depending on taxon-specific cellular requirements. In certain conditions cyanobacteria can form extensive blooms; this phenomenon arising from excessive nutrient input is usually of anthropogenic origin, resulting from a myriad of sources including point sources from municipal and industrial discharges, and non-point sources from agricultural run-off. This work is integrated with the activities carried out within a wider research project aimed at (a) characterizing the role of cyanobacteria as a good bioindicator of coastal water quality, (b) advancing a hierarchical monitoring approach using space-borne remote sensing to in-situ sampling and laboratory microscope analysis of cyanobacteria, (c) reporting on the taxonomic analysis of the cyanobacterial community in the coastal waters of Campania region in southern Italy, and (d) exploring the relationship of cyanobacteria with the terrestrial river basins draining to the coast. In this study, the occurrence of specific cyanobacteria species in extremely polluted environment has been investigated. Specifically, the target point has been selected based on the discharge from the wastewater treatment plant in Cuma, Campania region (Italy). These analyses can support environmental impact studies by governmental officials regarding aquatic pollution problems e.g. determining the effectiveness of wastewater plants in preventing eutrophication impacts within specific coastal areas. [ABSTRACT FROM AUTHOR]

The Caribbean sponge Pseudoceratina crassa yields six crasseride homologues, which are analogues of the glycolipids but are based instead on a five-membered cyclitol. Spectroscopic studies of their tetraacetates reveal a 1'-O-linked propyl 10'-methylhexadecyl ether sidechain. The homologues are differentiated from one another by their acylated branched chain at position-2 of the propyloxy component. Assays show a strong antifeedant action of the glycerides,suggesting their role as feeding deterrents.