The genus Haslea: dress up something old as something newJean-Luc Mouget1, Charlotte Falaise1, Roo Perkins2, Pamela Pasetto3, Andrzej Witkowski4, Romain Gastineau4

1 Laboratoire Mer Molécule Santé (EA 2160, FR CNRS 3473 IUML), Le Mans Université, Le Mans, France

2 School of Earth and Ocean Sciences, Cardiff University, Park Place, Cardiff, Wales, UK, CF10 3AT

3 Institut des Molécules et Matériaux du Mans (IMMM), Le Mans Université, 72085 Le Mans, France

4 Palaeoceanology Unit University of Szczecin Mickiewicza 18 PL-70-383 Szczecin, Poland



Keywords: aquaculture, biodiversity, diatom, Haslea, H2020, marennine-like pigments



The genus Haslea is a taxonomic unit of marine pennate diatoms defined by R. Simonsen in 1974, which refers to fusiform or lanceolate cells with a frustule made of two valves, each presenting straight striae, both transversally (transapical striae) and longitudinally (apical striae). Characteristically, Haslea frustule valves present a totally different aspect when comparing their external and internal surfaces. The former presents continuous longitudinal fissures, the latter is perforated by areolae, square to rectangular openings, forming grate-like bars. These two layers are assembled in a typical bi-layered structure. The genus Haslea type species is H. ostrearia, a tychopelagic/benthic/epiphyte organism that produces marennine, a water-soluble blue pigment responsible for the greening of oysters in Western France. Marennine is also a bioactive molecule, with antioxidant, antiproliferative, antibacterial and antiviral activities. Recently, the H2020 program GHaNA (The genus Haslea, new resource for biotechnology and aquaculture), a collaborative research project based on a partnership between academic and non-academic partners, has been funded to explore the biodiversity of the genus Haslea, and to characterize this bioresource for blue biotechnology applications in aquaculture, cosmetics and possibly food and health industry. Some progresses have been made regarding our knowledge about the biodiversity and genomics of blue Haslea, the chemical nature of marennine, the formation of blue Haslea blooms and the possible consequences of the amount of marennine-like pigments produced, and the exploitation of Haslea species, including silica skeletons, the wastes from frustules that could be used as inorganic “biocharges” in the formulation of new elastomeric materials.