Spatial diversity of planktonic protists in the Lagoon of Venice (LTER-Italy) based on 18S rDNA

Transitional waters are subject to a high degree of variability in space and time. In this study, protist plankton communities of the Lagoon of Venice were compared among four sites characterised by different environmental conditions with a metabarcoding approach. High throughput sequencing (HTS) of the V4-18S rDNA fragment in 32 samples collected on four dates, from April 2016 to February 2017, produced 1,137,113 reads, which were grouped into 4,058 OTUs at 97% similarity. Bacillariophyta and Ciliophora were the most abundant groups in the entire dataset in terms of read number (27.6% and 16.6%, respectively), followed by Dinophyta (10.9%), Cryptophyceae (9.7%), and Syndiniales (6.1%). The contribution of protist groups markedly varied across the seasons, but spatial differences were also recorded in the lagoon. In April, a higher contribution of Bacillariophyta characterized St1 and 5 (68.0% and 61.1%), whereas Sts2 and 3 showed a higher percentage of Ciliophora (18.6 and 23.4%, respectively) and dinoflagellates (10.3 and 7.7%). In July, diatom blooms occurred at Sts1, 2 and 3, with some differences in the dominant species. At St2 Dinophyta reached the highest contribution of the whole sampling period in the area (30.6%), while St5 was quite distinct, with a low contribution of diatoms and a dominance of Ciliophora (34.0%) and Trebouxiophyceae (36.4%). All the stations in November were characterized by relatively high abundance of Ciliophora (21.4-51.9%). In February, diatom contribution was relevant only at St5 (29.3%), Teleaulax acuta peaked at St3 (ca. 36%), Syndiniales at St2 (38.8%) and Dictyochophyceae at St1 (24.2%). The α-diversity indexes (observed OTUs, Shannon and Pielou evenness) showed a high variability over space and time. Overall, diversity and community composition were rather similar between the intermediate and deeper Sts2 and 3 on all sampling dates whereas they at time differed between the landward and shallow Sts1 and 5. While the most marked differences occurred over the temporal scale, the depth of the station and the relatedness with the external marine coastal environment appear to play a major role in the spatial distribution of protist communities within the lagoon

Bioactivity of Phycocolloids against the Mediterranean Protozoan Leishmania infantum: An Inceptive Study

Sulfated polysaccharides from marine macroalgae have been shown to possess a variety of biological activities against fungi, bacteria, viruses, and protozoa. In this study, the in vitro activity of algal polysaccharides against Leishmania infantum (Kinetoplastida: Trypanosomatidae) was investigated. The polysaccharides were extracted from different macroalgae of the Mediterranean Sea: Chaetomorpha linum, Agardhiella subulata, Gracilaria viridis, Gracilaria bursa-pastoris, Hypnea cornuta, Sargassum muticum, and Undaria pinnatifida. Preliminary results showed a good anti-leishmanial activity of the investigated species, encouraging the focus on their use as natural resources in order to match integrated management strategies for the employment of local macroalgae.Sulfated polysaccharides from marine macroalgae have been shown to possess a variety of biological activities against fungi, bacteria, viruses, and protozoa. In this study, the in vitro activity of algal polysaccharides against Leishmania infantum (Kinetoplastida: Trypanosomatidae) was investigated. The polysaccharides were extracted from different macroalgae of the Mediterranean Sea: Chaetomorpha linum, Agardhiella subulata, Gracilaria viridis, Gracilaria bursa-pastoris, Hypnea cornuta, Sargassum muticum, and Undaria pinnatifida. Preliminary results showed a good anti-leishmanial activity of the investigated species, encouraging the focus on their use as natural resources in order to match integrated management strategies for the employment of local macroalgae

Bio-Based Products from Mediterranean Seaweeds: Italian Opportunities and Challenges for a Sustainable Blue Economy

Seaweeds are attracting increasing attention as an alternative healthy food and renewable drugs source and as agents of climate change mitigation that provide essential ecosystem services. In this context, seaweeds represent marine resources capable of supporting and pursuing the objectives of the Sustainable Blue Economy and the Bio-Based Circular Economy. In this review, we analyze the state of seaweed bio-based products and research on the Mediterranean Sea from the last 20 years. Results of this analysis show a large number of investigations focusing on antimicrobial, antioxidant and anti-inflammatory activities compared to on biofuels and bioplastics. Attempts at seaweed farming, although generally very limited, are present in Israel and some North African countries. Lastly, we focus on the Italian situation—including research, companies and legislation on seaweed production—and we discuss gaps, perspectives and challenges for the potential development of a sustainable seaweed industry according to the Sustainable Blue Economy

Building a Natural and Cultural Heritage Repository for the Storage and Dissemination of Knowledge: The Algarium Veneticum and the Archivio di Studi Adriatici Case Study

The Archivio di Studi Adriatici (ASA) is a repository of the Institute of Marine Sciences (ISMAR-CNR) of Venice. The ASA repository, completely open source and open access, hosts natural collections, heritage books, documents, and maps of the Institute of Marine Sciences. It was developed following the discovery of a historical algal collection at the Biblioteca Storica di Studi Adriatici of Venice. This collection, after having been catalogued, has been digitized with a digital planetary scanner. Digitized specimens and metadata, compiled using Dublin Core and Simple Darwin Core formats, are hosted on a website, based on Fedora Repository and Islandora framework