Diving into the unknown: fourteen new species of haplosclerid sponges (Demospongiae: Haplosclerida) revealed along the Peruvian coast (Southeastern Pacific)

The Peruvian coast is certainly one of the poorest studied areas in the world for marine sponges biodiversity, with only 20 species registered so far from over 2,400 km coastline. In spite of its great species richness worldwide, there is not a single record of Haplosclerida in Peru. Accordingly, in this study we aimed to describe the species belonging to this order present in the relatively recent collections undertaken along the Peruvian coast by two of us (PhW, EH). Here, we describe fourteen new species, provisionally endemic to the Peruvian coast. This finding represents a major addition to the knowledge of the biodiversity of sponges along the Peruvian coast, increasing the list of species known to occur in this area by about 68%. This is also the largest single proposal of new Haplosclerida in over 37 years of sponge taxonomy worldwide. Niphates is for the first time recorded in the Southeastern Pacific, and an identification key to the Haplosclerida from the Peruvian coast is provided. Regarding the distribution of the described species, most of them—except for Chalinula chelysa sp. nov.—have a narrow geographic range, which might indicate their rarity or that the haplosclerid fauna in Peru is still poorly known.

A Multi-Species Investigation of Sponges’ Filtering Activity towards Marine Microalgae

Chronic discharge of surplus organic matter is a typical side effect of fish aquaculture, occasionally leading to coastal eutrophication and excessive phytoplankton growth. Owing to their innate filter-feeding capacity, marine sponges could mitigate environmental impact under integrated multitrophic aquaculture (IMTA) scenarios. Herein, we investigated the clearance capacity of four ubiquitous Mediterranean sponges (Agelas oroides, Axinella cannabina, Chondrosia reniformis and Sarcotragus foetidus) against three microalgal substrates with different size/motility characteristics: the nanophytoplankton Nannochloropsis sp. (~3.2 μm, nonmotile) and Isochrysis sp. (~3.8 μm, motile), as well as the diatom Phaeodactylum tricornutum (~21.7 μm, nonmotile). In vitro cleaning experiments were conducted using sponge explants in 1 L of natural seawater and applying different microalgal cell concentrations under light/dark conditions. The investigated sponges exhibited a wide range of retention efficiencies for the different phytoplankton cells, with the lowest average values found for A. cannabina (37%) and the highest for A. oroides (70%). The latter could filter up to 14.1 mL seawater per hour and gram of sponge wet weight, by retaining 100% of Isochrysis at a density of 105 cells mL−1, under darkness. Our results highlight differences in filtering capacity among sponge species and preferences for microalgal substrates with distinct size and motility traits.

Antibiotic and Heavy Metal Susceptibility of Non-Cholera Vibrio Isolated from Marine Sponges and Sea Urchins: Could They Pose a Potential Risk to Public Health?

Vibrio is an important human and animal pathogen that can carry clinically relevant antibiotic resistance genes and is present in different aquatic environments. However, there is a knowledge gap between antibiotic and heavy metal resistance and virulence potential when it is part of the microbiota from marine invertebrates. Here, we aimed to evaluate these characteristics and the occurrence of mobile genetic elements. Of 25 non-cholera Vibrio spp. from marine sponges and sea urchins collected at the coastlines of Brazil and France analyzed in this study, 16 (64%) were non-susceptible to antibiotics, and two (8%) were multidrug-resistant. Beta-lactam resistance (blaSHV) and virulence (vhh) genes were detected in sponge-associated isolates. The resistance gene for copper and silver (cusB) was detected in one sea urchin isolate. Plasmids were found in 11 (44%) of the isolates. This new information allows a better comprehension of antibiotic resistance in aquatic environments, since those invertebrates host resistant Vibrio spp. Thus, Vibrio associated with marine animals may pose a potential risk to public health due to carrying these antibiotic-resistant genes.

Pharmacological Activities of Extracts and Compounds Isolated from Mediterranean Sponge Sources

Marine pharmacology is an exciting and growing discipline that blends blue biotechnology and natural compound pharmacology together. Several sea-derived compounds that are approved on the pharmaceutical market were discovered in sponges, marine organisms that are particularly rich in bioactive metabolites. This paper was specifically aimed at reviewing the pharmacological activities of extracts or purified compounds from marine sponges that were collected in the Mediterranean Sea, one of the most biodiverse marine habitats, filling the gap in the literature about the research of natural products from this geographical area. Findings regarding different Mediterranean sponge species were individuated, reporting consistent evidence of efficacy mainly against cancer, infections, inflammatory, and neurological disorders. The sustainable exploitation of Mediterranean sponges as pharmaceutical sources is strongly encouraged to discover new compounds.

Natural Products Analysis of South Pacific Marine Sponges

<p>This thesis describes the isolation and structure elucidation of 15 new secondary metabolites from Tongan and New Zealand marine sponges. A total of 18 sponge specimens were subjected to an NMR-based screening method, of which four were analysed in detail. Examination of a two-sponge association, Stelletta crater and Desmacella dendyi from New Zealand, resulted in the isolation of two new 4-methylenesterols, craterols A (94) and B (95). To the best of the author’s knowledge, compounds 94 and 95 represent the first secondary metabolites to be reported from either species. Both 94 and 95 possess a double bond between C-5 and C-6, a feature that is unprecedented in this subgroup of marine natural products. An investigation of a Tongan sponge Zyzzya fuliginosa afforded two new pyrroloquinoline alkaloids, 6-bromodamirone B (182) and makaluvamine W (183). Makaluvamine W (183) contains an oxazole moiety, which is uncommon in this group of natural products. Both 182 and 183 lacked activity against the human promyelocytic leukemia cells (HL-60). Five new compounds were isolated from a Tongan sponge of the genus Leucetta, including two glycerol lipids (238 and 239), three glycerol ethers (244–246) and an imidazole alkaloid (243). Naamidine K (243) is a new addition to the naamidine family, while the glycerol metabolites are non-imidazole alkaloid additions to the group of compounds reported from this genus. A spectroscopic investigation into the Tongan sponge Cacospongia mycofijiensis yielded four new zampanolide analogues (282–285) and a new oxygenated sesquiterpene, isodictyodendrillin A (280). The isolation of the zampanolide analogues gives insight into the structure-activity relationship (SAR) in this family of compounds. Zampanolides B–D (282–284) displayed potent antiproliferative activity towards HL-60 cell lines in the low nanomolar range (3–5 nM), while zampanolide E (285) was significantly less potent with an IC50 value of 306 nM. In addition, the re-isolation of dactylolide (281) and zampanolide A (278) from this sponge, established a firm conclusion regarding the controversial configuration of dactylolide (281), which possesses the same absolute configuration as (–)-zampanolide A (278) and has a levorotatory optical rotation.</p>

Natural Products Analysis of South Pacific Marine Sponges

<p>This thesis describes the isolation and structure elucidation of 15 new secondary metabolites from Tongan and New Zealand marine sponges. A total of 18 sponge specimens were subjected to an NMR-based screening method, of which four were analysed in detail. Examination of a two-sponge association, Stelletta crater and Desmacella dendyi from New Zealand, resulted in the isolation of two new 4-methylenesterols, craterols A (94) and B (95). To the best of the author’s knowledge, compounds 94 and 95 represent the first secondary metabolites to be reported from either species. Both 94 and 95 possess a double bond between C-5 and C-6, a feature that is unprecedented in this subgroup of marine natural products. An investigation of a Tongan sponge Zyzzya fuliginosa afforded two new pyrroloquinoline alkaloids, 6-bromodamirone B (182) and makaluvamine W (183). Makaluvamine W (183) contains an oxazole moiety, which is uncommon in this group of natural products. Both 182 and 183 lacked activity against the human promyelocytic leukemia cells (HL-60). Five new compounds were isolated from a Tongan sponge of the genus Leucetta, including two glycerol lipids (238 and 239), three glycerol ethers (244–246) and an imidazole alkaloid (243). Naamidine K (243) is a new addition to the naamidine family, while the glycerol metabolites are non-imidazole alkaloid additions to the group of compounds reported from this genus. A spectroscopic investigation into the Tongan sponge Cacospongia mycofijiensis yielded four new zampanolide analogues (282–285) and a new oxygenated sesquiterpene, isodictyodendrillin A (280). The isolation of the zampanolide analogues gives insight into the structure-activity relationship (SAR) in this family of compounds. Zampanolides B–D (282–284) displayed potent antiproliferative activity towards HL-60 cell lines in the low nanomolar range (3–5 nM), while zampanolide E (285) was significantly less potent with an IC50 value of 306 nM. In addition, the re-isolation of dactylolide (281) and zampanolide A (278) from this sponge, established a firm conclusion regarding the controversial configuration of dactylolide (281), which possesses the same absolute configuration as (–)-zampanolide A (278) and has a levorotatory optical rotation.</p>