Biodiversity of the genus Haslea and possible applications

Jean-Luc Mouget1, Romain Gastineau2, Vona Meleder3, Alexandra Petit3, Michel Poulin4, Guillaume Masse5, Rupert G. Perkins6, Nicolai A. Davidovich2, Andrzej Witkowski2

 

1 FR CNRS 3473 IUML, Mer-Molécules- Santé (MMS), Le Mans Université, France

2 Palaeoceanology Unit, University of Szczecin, Poland

3 FR CNRS 3473 IUML, Mer-Molécules-Santé Université de Nantes, France

4 Research and Collections, Canadian Museum of Nature, Ottawa, Canada

5 Unité Mixte Internationale Takuvik, Université Laval, Québec, Canada

6 School of Earth and Ocean and Sciences, Cardiff University, Cardiff, United-Kingdom

 

The genus Haslea is a taxonomic unit of pennate diatoms referring to fusiform or lanceolate cells with a frustule made of two valves, each presenting straight striae, both transversally and longitudinally. 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 areolar, square to rectangular openings, forming grate-like bars. These two layers are held together and assembled in a typical sandwich-like 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, and blue Haslea have a high potential for use in existing oyster farming, for the production of pigments and bioactive compounds with natural antibacterial or cytostatic properties, and for novel applications as an industrial colouring agent. The H2020 project GHaNA (The genus Haslea, new resource for biotechnology and aquaculture) has been funded to explore the genus Haslea for blue biotechnology applications. This project is a collaborative research program based on a partnership between academic and non-academic partners. It will determine the biological and chemical diversity of Haslea diatoms and will develop mass-scale production processes, to achieve viable industrial production of biomass and associated high-value compounds, including terpenoids, marennine-like pigments and lipids. Moreover, silica skeleton wastes from frustules could be exploited as inorganic biocharges in the formulation of new elastomeric materials. These objectives will be achieved through fundamental and applied research to isolate fast-growing strains of Haslea, optimise their growth environment and cultivation system (ad hoc photobioreactors) to increase the production of marennine and other high-value compounds, develop blue biotechnology specifically applicable to benthic microalgae (biorefinery approach), and to explore the potential for industrial exploitation of colouring and bioactive compounds in commercial aquaculture, food production, cosmetics and health.