Phycology

The diversity of cyanobacteria from the semi-arid region of Rajasthan, India, remains vastly unexplored and warrants systematic investigation. We isolated two cyanobacterial strains (SN2022/33 & AT2016/25) of non-heterocytous, filamentous cyanobacterium from samples of sandy soil biological crusts and investigated them using a polyphasic approach. Based on 16S rRNA gene sequence identity, both strains formed a distinct lineage, with 16S sequence identity (p-distance) < 95% to the closest sister genera Trichocoleus, Venetifunis, Trichothermofontia, and Pinocchia. Analyses of 16S-23S Internal Transcribed Spacer (ITS) secondary structures (D1-D1′, BoxB, and V3 helixes) yielded substantial differences from phylogenetically associated taxa. Morphologically, both strains corresponded to members of the family Trichocoleusaceae (Leptolyngbyales), with tapered filaments and conical-pointed end cells. Most significantly, this taxon exhibited a form of true branching, with prolific unilateral or bilateral extrusions, something that had previously been the exclusive purview of members of the Nostocaceae. The combined evidence from conventional and molecular studies supports the recognition of the isolates as a novel taxon hereby described as Edaphifilum ginni gen. et sp. nov., in accordance with the International Code of Nomenclature (ICN) for Algae, Fungi, and Plants. Full article

Soil algae are important photoautotrophs, yet drivers of their diversity in peri-urban landscapes and across soil horizons remain poorly resolved. We used ITS2 metabarcoding to profile eukaryotic algal and fungal communities in 34 samples from Mexico City’s peri-urban conservation soils. Samples represented three Soil Systems: agricultural mineral soil, forest mineral soil, and forest litter, collected in two boroughs (Xochimilco and Tlalpan). We inferred amplicon sequence variants (ASVs), then alpha diversity and Bray–Curtis turnover were analyzed against edaphic and stoichiometric variables using random forests and PERMANOVA, and compared algal with fungal turnover. We recovered 662 algal ASVs spanning eight classes dominated by Trebouxiophyceae and Chlorophyceae. Litter was the richest and most distinct compartment with a high prevalence and abundance of lichen-associated taxa, whereas mineral soils were dominated by Chlorophyceae. Random forests ranked N/P ratio as the top predictor of both diversity indices. PERMANOVA indicated that the Soil System explained the largest single fraction of turnover. Algal and fungal turnover were positively correlated in mineral soils. Together, soil management practices, vertical compartmentalization and measured edaphic gradients were associated with community differences. These results point to potential algal management practices that could enhance peri-urban soil conservation and agroecological productivity. Full article

Augmenting aquaculture feeds with black soldier fly (Hermetia illucens L.) larvae is an emerging solution to the industry’s fishmeal and fish oil dependence. However, the larva’s nutritional plasticity often results in bioaccumulation of metals from the rearing substrates. Larvae can be nutritionally enriched with microalgae, but research investigating growth impacts and metals uptake are lacking. In this study, a Stichococcaceae algae strain that is used to phycoremediate effluent from commercial anaerobic digesters was investigated as a rearing substrate. Larvae were reared on chicken feed enriched with stepped ratios of algae and spent coffee grounds (a reference waste feed). Growth, survival and metals content (ICP-OES) were recorded when 10% of larvae were prepupal. Survival was >98.5% across all treatments with a trend of increased growth with microalgal inclusion, and no significant impact of metals on growth. Metals uptake as determined by a bioaccumulation factor was significantly lower in the highest algae treatment compared to the coffee-only treatment. Larvae consistently accumulated cadmium and lead whereas arsenic bioaccumulation was only observed in three treatments. Cadmium had the highest bioaccumulation factor (up to 4.06) and arsenic the lowest (down to 0.41). Larvae did not exceed current European Union maximum metal ions levels for inclusion into aquafeeds. These findings highlight the potential of using Stichococcaceae to enrich black soldier fly larvae, offering a dual sustainable solution for wastewater remediation and aquaculture feed provision. Full article

Thermomineral springs provide stable thermal and geochemical regimes that promote the development of dense phototrophic biofilms dominated by cyanobacteria. Phototrophic communities were investigated across eight thermomineral springs in Serbia (six in eastern and two in central Serbia) using an integrated morphological, ecological, and molecular approach. Biofilms were sampled in 2024 from contrasting microhabitats (submerged, overflow, and splash/aerosol-exposed zones) and biomass was assessed through chlorophyll a (Chl a) quantification. Cyanobacterial taxa were identified via light microscopy using standard taxonomic keys and simple trichal morphotypes represented the highest diversity; Leptolyngbya showed the broadest distribution, while heterocytous taxa (Calothrix) were rare. A total of 73 cyanobacterial taxa were recorded across the eight investigated springs, with richness ranging from 1 to 33 taxa per locality; the highest richness was observed in Brestovac (33 taxa), followed by Šarbanovac (28) and Nikoličevo (22). Molecular characterization (16S rRNA) of nine cultured isolates revealed multiple filamentous cyanobacterial lineages, including Elainella (Oculatellales) and Wilmottia-related clades, while several isolates showed “Leptolyngbya-like” BLASTn affinities but phylogenetically separated clustering. Overall, the results indicate that Serbian thermomineral springs host diverse cyanobacteria-dominated biofilms shaped by local physical and chemical gradients and microhabitat structure and represent promising reservoirs of thermotolerant strains for further biotechnological use. Full article

Poterioochromonas is a typical mixotrophic chrysophyte that plays an important ecological role in natural aquatic environments and has received particular attention from morphological and ecological perspectives over the last few decades because of its peculiar mode of feeding and relevance for practical applications. However, the taxonomic classification of this genus remains controversial, and the true extent of its diversity remains largely unknown. Here, we use a complementary approach of culturing, morphological and phylogenetic analyses, and sequence database mining to address this issue. We collected 16 cultures of Poterioochromonas to determine the essential morphological characteristics and clarify the taxonomy and phylogeny of the genus. Our results confirmed that all Poterioochromonas strains produce lorica, which is the diagnostic character for the genus. We suggest that the shape of the lorica cup and the morphology of the cyst could be used as diagnostic characteristics to differentiate different species within the genus. Molecular phylogenetic analysis based on the SSU rDNA and rbcL gene sequences confirmed the monophyly of Poterioochromonas, which is subdivided into heterotrophic and mixotrophic clades. Comparative analysis of six molecular markers revealed that the COI gene is the most sensitive for distinguishing both inter- and intraspecific relationships. An exhaustive screening of the NCBI GenBank database and publicly available amplicon sequencing datasets revealed 100 SSU rDNA gene sequences for Poterioochromonas. The results showed that many soil-derived environmental sequences grouped with heterotrophic Poterioochromonas and indicated that the heterotrophic representatives of the genus are abundant in the soil environment. The results also revealed that many environmental sequences did not group with any reference sequences of known species, indicating that the genus Poterioochromonas is much more diverse than previously thought. This study contributes to a clearer taxonomic and distributional framework for Poterioochromonas, thereby facilitating future basic and applied research on this genus and similar mixotrophic chrysophytes. Full article

Plant pathogens can result in massive crop destruction globally, thereby increasing starvation, while conventional or synthetic pesticides are harmful to the environment and human health. The urgent need for sustainable and eco-friendly disease management strategies has driven interest in natural biocontrol agents. Ulva sp. produce a sulfated polysaccharide named ulvan, which serves as a multifunctional biostimulant with pronounced antibacterial, antiviral, and antifungal properties against a broad spectrum of phytopathogens. Its complex anionic structure plays a dual role by directly inhibiting pathogen growth through cell membrane disruption and biofilm suppression, while simultaneously inducing plant defense mechanisms through reactive oxygen species (ROS) signaling and activation of pathogenesis-related (PR) proteins. Recent advances in ulvan extraction, purification, structural analysis, and inhibitory mechanisms of phytopathogens are discussed in this review. Furthermore, the biodegradability and biocompatibility of ulvan highlight its potential applications beyond agriculture, including biomedical and sustainable biomaterial development. By comprehensively analyzing the bioactivity spectrum and mechanistic pathways of ulvan, this review proposes strategic approaches for integrating ulvan into environmentally friendly plant disease management systems, supporting its role in advancing a circular bioeconomy. Full article

Algae rarely occur as solitary phototrophs in nature or engineering; instead, they are embedded in complex bacterial consortia that control their physiology, productivity and ecological performance. The phycosphere, a microscale niche rich in algal exudates, promotes extensive metabolic exchange and chemical signaling, defining these associations. Bacteria capitalize on the dissolved organic carbon released by algae, providing growth supporting molecules such as vitamins, trace metals, and siderophores, as well as regenerated inorganic nutrients. Bidirectional beneficial interactions range from obligate mutualism to facultative commensalism and antagonism, depending on environmental context and community membership. Bacterial partners can stimulate algal growth, morphogenesis, and stress tolerance, as well as modulating defense and programmed cell death during the decline and bloom succession of algae resulting from algicidal taxa. Metabolic cooperation, QS signaling, extracellular enzyme activity, and chemically induced gene expression produce the exometabolome in the phycosphere, which in turn reprograms gene expression in all partners. Recent advances in multi-omics toolboxes, single-cell isotopic analyses, and microfluidics have greatly enhanced our understanding of the functional and spatiotemporal orientation of algal microbiomes. Ecologically, algal–bacterial interactions manage the phytoplankton community structure, control HABs, and modulate carbon and nutrient fluxes in both marine and freshwater realms. Biotechnologically, engineered algal–bacterial consortia are a promising tool for enhancing biomass production, stabilizing large-scale cultivation, improving wastewater treatment, and upgrading biofuels and fine chemicals. Despite these notable research advances, the context- and species-dependent complexity of multispecies interactions remains a major obstacle to their practical modeling and scalable implementation. Integrative research frameworks that combine molecular, ecological, and bioengineering approaches are urgently needed to unlock the full potential of sustainable applications in the future. Full article

Aquafeed formulations often rely on lipid sources that supply n-3 fatty acids but are vulnerable to oxidation, highlighting the need for ingredients that clarify how n-3 delivery and oxidative stability interact. Biomass from Dunaliella tertiolecta and Tetraselmis chuii were chemically characterized to examine this relationship using fatty acid profiles, lipid quality indices, and antioxidant activity. Dunaliella contained α-linolenic acid as its main n-3 fatty acid (27.19% of total FA), whereas Tetraselmis contained eicosapentaenoic acid (5.94%) and minor docosahexaenoic acid (0.77%). These differences produced distinct peroxidizability index values: 82.5 in Dunaliella and 101.4 in Tetraselmis, reflecting the contrasting susceptibilities of their lipid fractions to oxidation. Antioxidant measurements also diverged; Dunaliella showed higher reducing activity (FRAP: 200.33 mg TE g⁻¹ db), while Tetraselmis exhibited greater DPPH activity (69.62 mg TE g⁻¹ db) and flavonoid content (25.73 mg EEPC g⁻¹ db). The combination of high EPA with higher PI in Tetraselmis and lower PI with stronger reducing capacity in Dunaliella highlights the conditions under which each biomass may influence n-3 availability and oxidative stability in formulated feeds. These results establish a functional decision framework for selecting and combining microalgal ingredients based on trade-offs between HUFA delivery and oxidative stability in aquafeed formulation. Full article

Brown seaweed Alaria esculenta has potential as a sustainable feed for ruminants, but it deteriorates quickly after harvesting. This study evaluated silage as a preservation method and analyzed its effects on nutritive value and anti-methanogenic properties. Four treatments were tested: no additive, formic acid, lactic acid bacteria (LAB), and pre-wilting at 30% dry matter plus LAB (PLAB). Chemical composition and in vitro fermentation using sheep rumen fluid were analyzed. Ensiling reduced fiber components and polyphenols but did not affect gross energy, and increased gas production and total volatile fatty acids, indicating improved fermentability, especially in PLAB treatment. However, overall nutritive value remained lower than that of alfalfa hay and concentrate. Methane production increased after ensiling due to higher fermentation levels. Despite this, the methane-to-VFA ratio in all the seaweed samples was about one-third of that of conventional feeds, indicating anti-methanogenic properties. No differences in this ratio were found between fresh and ensiled seaweed, indicating that these anti-methanogenic properties were preserved. Overall, ensiling is a viable method to stabilize A. esculenta, improving its fermentability and maintaining its capacity to reduce methane emissions, although its nutritional value remains relatively low compared to traditional ruminant feeds. Full article

The rapid proliferation of microalgae in aquatic systems poses significant environmental and public health challenges, particularly in regions lacking adequate water treatment facilities. This study reports a sustainable approach for microalgae removal through the development of low-cost membranes derived from expanded polystyrene (EPS) waste and modified with polyethylene glycol (PEG) as a pore-forming agent. Membranes were fabricated via non-solvent-induced phase separation with PEG loadings of 0–20 wt.% and characterized in terms of morphology, porosity, wettability, and hydraulic performance. Filtration efficiency was evaluated using Spirulina platensis as a model microalga. Incorporation of PEG (up to 15 wt.%) enhanced membrane porosity (77–84%), improved hydrophilicity (water contact angle reduced from 68° to 48°), and increased water flux (10.98–39.2 L·m⁻²·h⁻¹), while maintaining complete microalgal rejection (100%). Optimized membranes exhibited asymmetric finger-like structures, contributing to improved permeability. Full article

This study integrates a Systematic Literature Review (PRISMA 2020) with a bibliometric analysis to examine how global research on microalgae biotechnology has incorporated innovation management, technology transfer, and dynamic capabilities. A total of 418 records were retrieved from Scopus and Web of Science for the period 2015–2025, of which 133 studies met the inclusion criteria after deduplication and screening based on an adapted PICO framework. Bibliometric indicators were generated using Bibliometrix (R) and VOSviewer (version 1.6.20) to identify publication trends, leading countries, collaboration networks, and thematic structures. The results suggest a progressive shift from predominantly techno-biological research toward approaches that emphasize technology maturity, innovation processes, and organizational capabilities. Three main analytical outcomes were identified: (i) studies addressing dynamic capabilities related to organizational learning and strategic reconfiguration (14.1%); (ii) research focused on technology readiness levels (TRL) and technology adoption, reflecting the transition from laboratory-scale research to pilot and industrial implementation (22.9%); and (iii) analyses of innovation ecosystems highlighting university–industry collaboration, governance mechanisms, and bioeconomy-oriented policies (17.7%). Nevertheless, approximately 22% of the literature remains exclusively technical, indicating a persistent disciplinary bias. By integrating innovation management, technology transfer, and dynamic capabilities as complementary analytical lenses, this review develops a comprehensive framework for understanding how microalgae biotechnology contributes to the consolidation of sustainable bioeconomy-oriented innovation ecosystems. The findings underscore the potential of technology governance and TRL-based management to bridge the gap between scientific research and industrial deployment. Full article

Seaweed cultivation is a primary economic driver in Tawi-Tawi, Philippines, yet the industry faces significant challenges regarding the physiological integrity of propagules during inter-island transit. This study evaluated the effects of varying transportation durations (0, 12, 24, 36, and 48 h) on the specific growth rate (SGR), occurrence of ice-ice disease, and dry biomass yield of Kappaphycus striatus over a 30-day cultivation period using a modified fixed-off-bottom method. The results demonstrated that transportation duration significantly influenced SGR at Day 10 and Day 30 (p < 0.05), whereas no significant differences were observed at Day 20. The control group (0 h transport) exhibited the highest growth performance (4.61 ± 0.18% day⁻¹ at Day 10), whereas the lowest growth was recorded in the 48 h treatment group at Day 30 (0.93 ± 0.49% day⁻¹). Pathological assessment indicated that ice-ice disease occurrence was highly significant during the initial recovery phase (Days 1–7) and at Day 20 (p < 0.05). Specifically, propagules subjected to 48 h transport reached 100% disease incidence within the first four days post-transplant, while the 36 h group reached 96.67%, highlighting acute transport-induced stress. Although the 48 h group exhibited significantly higher initial ice-ice spot counts (p < 0.05), statistical differences diminished between Day 10 and Day 30, suggesting a degree of physiological resilience and recovery capacity. Ultimately, prolonged transportation exceeding 24 h induced severe dehydration stress, resulting in a 62.7% reduction in SGR by Day 30 compared to the control. These findings suggest that seedling transport should be optimized within a 24 h window to preserve thallus vigor and maximize sustainable yields. Future research should investigate post-transport recovery protocols to mitigate the effects of unavoidable shipping delays. Full article

Seaweeds are photosynthetic organisms with ecological, social, and economic significance, and they serve as effective bioindicators in marine ecosystems. This study assessed trace element concentrations in beach-cast seaweeds collected from four beaches along the Espírito Santo coast in southeastern Brazil—an area impacted by mining-related contamination. Samples of Zonaria tournefortii (J.V. Lamouroux) Montagne and Sargassum natans (Linnaeus) Gaillon, gathered during low tide (July–August 2022), were analyzed for 15 elements. Statistical analysis using the Kruskal–Wallis test revealed significant interspecific differences in the accumulation of several metals. Aluminum (Al), iron (Fe), and magnesium (Mg) were the most abundant (>100 mg/kg), while minor elements (<100 mg/kg) included barium (Ba), arsenic (As), zinc (Zn), vanadium (V), nickel (Ni), chromium (Cr), copper (Cu), lead (Pb), cobalt (Co), cadmium (Cd), silver (Ag), and mercury (Hg). Elemental profiles exceeded those reported in other global regions and closely resembled iron ore tailings. Most elements had relatively higher concentrations on the beaches of Imigrantes, in the north of the state. These findings are the first for beach-cast seaweeds in this region, suggesting that this contamination indicates the legacy of the mining industry from southeastern Brazil. Full article

Ruminants significantly contribute to global methane (CH₄) emissions, necessitating the development of dietary mitigation strategies. This study evaluated five Bangladeshi seaweeds (brown, red, and green types) from Saint Martin Island for their anti-methanogenic potential through phenotypic identification, proximate analysis, and in vitro fermentation assessment. Significant interspecies variation was (p < 0.001) observed in dry matter (DM: 82.1–99.9%), acid detergent fiber (ADF: 17.4–24.9%), neutral detergent fiber (NDF: 29.6–43.6%), and dry matter degradability (DMD: 43.9–58.7%), while crude protein (CP) remained consistent (p = 0.574). After 48 h of fermentation, total gas (1.3–22.1 mL/g DM) and CH₄ yield (0.04–1.6 mL/g DM) varied markedly (p < 0.01). DMD was strongly correlated with total gas and CH₄ production. Crucially, both ADF and NDF showed a positive correlation with total gas and CH₄ production. However, NDF displayed a weak positive correlation with DMD. These findings suggest atypical fiber fraction dynamics, contrasting with terrestrial forages. Supplementation effects of two red seaweeds, SW-4 (Gracilaria parvispora) and SW-5 (Asparagopsis taxiformis), on Napier grass were assessed at 5% and 10% inclusion levels. SW-5 reduced CH₄ by 52.7% when co-fermented with Napier grass at a 10% inclusion level for 48 h, whereas SW-4 showed no significant effect. These results highlight SW-5 as a promising dietary supplement to reduce enteric CH₄ in ruminants, suggesting further in vivo validation for optimal use. Full article

Harmful algal blooms (HABs) pose a serious threat to public health, aquaculture, and coastal ecosystems, making the development of tools for their rapid and specific detection a high priority. Laser-induced fluorescence (LIF) spectroscopy enables the assessment of characteristic photosynthetic pigments, offering a pathway to automated, high-throughput monitoring systems. Here, we investigate the temperature dependency of LIF spectra in the range of 20–80 °C to establish stable fluorescence fingerprints for the harmful microalgae Alexandrium catenella. Critically, we demonstrate that the relationship between temperature and both fluorescence intensity and spectral position remains consistent over 35 days of cultivation, independent of culture age. We performed complementary flow cytometric and pigment analyses (HPLC) to characterize the culture’s physiological state. Over the 35-day period, cell concentration increased 20-fold, while cell size, granularity, and fluorescence spectra remained stable. A transient decrease in fluorescence intensity observed on day 10 coincided with a drop in peridinin concentration, confirming the link between the spectral signal and pigment composition. Obtained results validate the use of this fluorescence fingerprint for the reliable identification of A. catenella without prior knowledge of the culture’s age—a key advantage for field applications. Furthermore, these fingerprints remained clearly distinguishable even when the culture was diluted with seawater to just 3% of its original volume, underscoring the potential sensitivity of this approach for early warning systems. Full article

Bodanella lauterborni W.M. Zimmermann and Heribaudiella fluviatilis (Areschoug) Svedelius are members of brown algae (Phaeophyceae) that exclusively inhabit freshwater habitats. Heribaudiella fluviatilis is the most frequently reported freshwater brown alga, widely distributed in the Northern Hemisphere. In contrast, B. lauterborni, one of the rarest algae globally, has been reported in only four glacial Alpine lakes and has not been observed in nature for nearly 50 years. Since 2019, the species has been considered locally extinct at its type locality, and its presence in the other three lakes is also questionable. Here, we report the occurrence of B. lauterborni in three springs on the Vlasina Plateau (Southeast Serbia), being the first finding of the species in Southeast Europe and the fifth discovery globally in environmental conditions not previously described for the species. We also provide detailed data on the morphology, ecology, and biogeography of B. lauterborni and H. fluviatilis. Additionally, we report the non-obligate association Hildenbrandio rivularis-Heribaudielletum fluviatilis discovered in two rivers. Our findings significantly expand the known ecological and geographical range of phaeophytes, highlighting Southeast Europe as a refugium for freshwater Phaeophyceae biodiversity. Full article

Different cyanobacterial species have been shown to be a valuable source of biologically active compounds with immunomodulatory activity. To date, little is known about members of the genus Tolypothrix (Cyanophyceae). Therefore, the present study focuses on five Tolypothrix strains (T. tenuis PACC 5497, T. tenuis PACC 8648, T. distorta SAG 1482-2, T. distorta CCALA 194, Tolypothrix sp. PACC 5501) that were not previously evaluated for specific morphological characteristics and immunomodulatory potential toward human immune cells. Cyanobacterial cultures were studied by light and transmission electron microscopy (TEM). Peripheral blood leukocytes were isolated from patients with inflammatory conditions and treated ex vivo with Tolypothrix non-polar extract fractions. Following treatment, the cells were analyzed by flow cytometry, and cytokine concentrations in culture supernatants were quantified by ELISA. Light microscopy observations showed that the cultures established from four of the strains have morphological features that correspond to T. tenuis Kützing (1843) ex Bornet et Flahault 1887 and T. distorta Kützing (1843) ex Bornet et Flahault. TEM analyses indicated parietal arrangement of cellular thylakoids in all strains, but T. distorta CCALA194 and Tolypothrix sp. PACC 5501 also displayed fascicular thylakoid arrangement. Immunophenotypic analyses revealed significantly increased proportions of T, NK, and B lymphocytes in leukocyte cultures treated with Tolypothrix extracts compared to the untreated controls. The concentrations of proinflammatory cytokines were lower in the culture medium of treated cells, while levels of the anti-inflammatory cytokine interleukin-10 remained stable, except in cultures treated with T. distorta SAG 1482-2 extract. The present study provides the detailed morphological characteristics of five strains of the genus Tolypothrix and indicate that non-polar extract fractions derived from the strains exert immunomodulatory effects on human leukocytes. Full article

The present study provides an exhaustive exploration of twelve macroalgal species from the Adriatic Sea, including seven brown algae (Ericaria amentacea, Fucus virsoides, Cutleria multifida, Cystoseira compressa, Cystoseira corniculata, Gongolaria barbata and Padina pavonica), three green algae (Codium adhaerens, Codium vermilara and Ulva lactuca), and two red algae (Scinaia furcellata and Asparagopsis taxiformis). Matrix solid-phase dispersion (MSPD) was applied as the extraction technique, using generally recognized as safe (GRAS) solvents. The bioactive profile of the extracts was assessed through the quantification of total phenolic content (TPC) and antioxidant activity. Among the three phyla, U. lactuca, F. virsoides and S. furcellata exhibited the highest TPC (0.8, 26 and 3.0 mgGAE·g⁻¹) and antioxidant activity (1.9, 38 and 7.5 mgTE·g⁻¹), respectively. Targeted HPLC-MS/MS analysis enabled the identification of nineteen phenolic compounds across all taxa. Chlorophyta showed a characteristic profile enriched in coumarins, benzaldehydes and flavanones, including the selective detection of 7-hydroxycoumarin in species with higher antioxidant potential. Additionally, compounds such as chlorogenic, rosmarinic and caffeic acids exhibited taxon-specific distributions that may explain differences in antioxidant activity. Complementary untargeted ultra-high performance liquid chromatography quadrupole time-of-flight (UHPLC-QToF) metabolomics analysis provided broader coverage, revealing eighty metabolites spanning phenolics, sugars, organic acids, lipids, amino acids and their derivatives. Notably, the proposed detection of fatty acid esters of hydroxy fatty acids (FAHFAs) represents the first report of these compounds in macroalgae, alongside a pronounced presence of sulphated phenolics. Overall, these findings provide a robust baseline on the bioactivity and chemical composition of Adriatic macroalgae, highlighting their value as a natural source of functional compounds. Full article

A comparative analysis of the long-term dynamics of phytobenthos on the Black Sea coast from 1964 to 2020 has been conducted. The aim of the work was to assess changes in species composition, quantittive characteristics, and distribution of bottom vegetation under the influence of natural and anthropogenic factors. The research was carried out at three transects using standard hydrobotanical methods and analysis of climatic data. The results revealed significant structural reorganization of the communities: a decrease in the proportion of key brown algae (Ericaria crinita and Gongolaria barbata) by the middle of the observation period with partial recovery by 2020, an overall increase in biomass and species diversity, and increased role of epiphytes and green algae. An expansion of the depth range of the phytal zone and an increase in the presence of the deep-water species Phyllophora crispa were established. The main drivers of the transformation are increased anthropogenic pressure and climate change, which aligns with global trends. The obtained data are important for developing measures to preserve coastal ecosystems and can be used in monitoring the ecological state of the aquatic area. A promising direction for further research is the quantitative assessment of the role of the macrophytobenthos in this area in carbon sequestration. Full article