''Delisea pulchra'' is a

red algae Red algae, or Rhodophyta (, ; ), make up one of the oldest groups of eukaryotic algae. The Rhodophyta comprises one of the largest Phylum, phyla of algae, containing over 7,000 recognized species within over 900 Genus, genera amidst ongoing taxon ...

found in Southern

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

, the

Subantarctic Islands The sub-Antarctic zone is a physiographic region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region inc ...

and the

Antarctic Peninsula The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martin in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctica. ...

. It produces a range of

secondary metabolite Secondary metabolites, also called ''specialised metabolites'', ''secondary products'', or ''natural products'', are organic compounds produced by any lifeform, e.g. bacteria, archaea, fungi, animals, or plants, which are not directly involved ...

s called

halogenated In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs ...

furanones that have ecological roles as defenses against

epiphyte An epiphyte is a plant or plant-like organism that grows on the surface of another plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphyt ...

s and herbivores.

Halogenated furanones in ''Delisea pulchra''

Localisation of furanones

Furanones are localised in the central vesicle of gland cells in ''D. pulchra''''.'' The presence of a series of conjugated double bonds in the structure of furanones cause these compounds to fluoresce when excited by the wavelength close to UV. Four main types of

furanones were found in this species. Prevention of biofilm on Delisea pulchra's surface The halogenated furanones produced by ''D. pulchra'' are structurally similar to bacterial signalling molecules called acylated homoserine lactones (AHL). There is evidence that the halogenated furanones attach to the bacteria receptor proteins for AHLs disabling bacterial communication. In this way the seaweed can prevent biofilm accumulation on its surface.

References

Bonnemaisoniales Algae of Australia {{rhodophyta-stub