Isolation and identification of microalgal strains with potential as carotenoids producers from a municipal solid waste landfill.

Derived from their great capacity of adaptation, microalgae have several industrial applications, including pigment production for nutraceutical sector. However, the scarcity of studies on the diversity and life histories from several environments, highlight the need for more research on new species and habitats. Based on this, the present study assessed the microalgal diversity in water bodies of a municipal solid waste (MSW) landfill in Asturias (Spain). A total of 14 strains were successfully isolated and scaled up in liquid monocultures. They were identified through a combination of morphologic features with molecular assignation by DNA barcoding via the 18S and ITS1-5.8S-ITS2 genes. The results of the genetic procedures (BLAST assignments and the 18S and ITS1-5.8S-ITS2 genealogies) showed that 10 of the 14 assayed isolates were identified at the species level. The available genetic data were not sufficient for species classifications of the remaining isolates. It is possible that some might be new species not previously studied or described. Indeed, a new species, Coelastrella cogersae, was proposed in this study. Moreover, 3 of the 14 isolates (including the newly proposed species) exhibited caretogenic activity under specific conditions during the culture. These results are a great step forward in both the screening of lesser-known environments and the discovery of new sources of bioactive compounds. The study could be of great value to the nutraceutical industries and markets.

Development and validation of eDNA markers for the detection of Crepidula fornicata in environmental samples.

The invasive Crepidula fornicata caused major problems along the European Atlantic coast, especially in France and Netherlands where high densities leads on changes in the habitat, disturb native marine wildlife as well as it originates competition for space and food. Despite its dangerous invasive nature, regular monitoring to alert about its presence in risk areas, like the south Bay of Biscay (Spain and south France), is not done yet. Here, we developed a species-specific marker to detect the presence of C. fornicata in environmental samples (eDNA) of seawater. The novel C. fornicata specific primers amplified a region of 239 bp within the COI gen. We employed this tool to check its presence in 6 estuaries of the Cantabrian Sea, an area comprised between the Spanish and French limits of the previously reported presence of this limpet in the south Bay of Biscay. The presence of C. fornicata was confirmed in A Coruña (Galicia, Spain), Eo and Villaviciosa estuaries (Asturias, Spain) while it was not detected in Santander, Bilbao (Spain), and Bayonne (France). This new method to detect C. fornicata could be easily implemented in regular monitoring to prevent and manage future invasions of this species.