Microalgae

Microalgae are single-celled organisms that use photosynthesis :

  • Microalgae use sunlight (or artificial light) as an energy source to convert carbon (especially carbon dioxide) into organic matter

  • It then creates a “green mashed potato” that can be used for different purposes or transformed into biofuel; this is the biomass. Humans use biomass, as well as the animals that consume it, as food, extracts, pigments, fibers, materials and energy. Biomass is also used for heating, electricity production, transportation (thanks to biofuels) and the development of bioproducts such as plastic substitutes.

What are microalgae used for ?

– They play a major role in carbon mitigation

– They offer an additional source of biomass, without creating tension on the markets for food raw materials and with a higher surface productivity than terrestrial plants

– Their genetic and physiological diversity opens the door to many new applications

– An interesting property of microalgae is the speed of their development. A microalga doubles its mass every day: by capturing light photons and fixing CO2. It grows during the day and divides into two daughter cells at night. There is no terrestrial plant that is capable of such exponential growth.

– Microalgae are composed of lipids (between 5 and 90% of the microalgae depending on the species), glycerols, fatty acids (saturated or not), proteins (up to 65%), carbohydrates (starch, sugars, glucose, polysaccharides) and pigments. The composition of microalgae varies according to the species and therefore their use. The consumption of CO2 also varies according to the type of microalgae: their capacity to attenuate carbon is therefore varied.

– Scientists estimate that there are between 500,000 and 3,000,000 species of microalgae. For now, about 30,000 have alreadỳ beeń studied. Of these 30,000 species, only about 20 are cultivated. Of these 20 cultured species, there are about 20,000 strains (microbial population) available in the collections. With a reduction rate of 30% due to redundancies, this gives a total of about 5,000 strains.

les différentes espèces de micro-algues

Biotechnology : main cultivated species

Out of 30,000 known species of microalgae, Planktonid has in-depth knowledge of the cultivation of the most productive and interesting microalgae species :

Nannochloropsis gaditana
Tetraselmis chuii
Scenedesmus almeriensis
Scenedesmus obliques
Nannochloris spp.

Chlorella vulgaris
Chlorella spp.
Arthospira platensis (spiruline)
Dunaliella tertiolecta
Dunaliella salina

Porphyridium purpureum
Chaetoceros spp
Odontella aurita
Phaedactylum tricornutum
Haematococcus pluvialis

Microalgae exploitation process

  1. For 1 Kg of CO2, we produce 0.6 Kg of Biomass. This figure is very little variable from one species to another.
  2. Production of valuable materials. Capacity of assimilation and thus of associated treatment.