Screening of the best strain in fonction of different parameters like: the type of effluents / substrat aimed to be used for production, the type of market objective (pharmaceutical, cosmetics, nutraceutical, food, feed, agriculture, bio-based materials, wwt, biofuel...), the geographical location of the production facility, the culture technology type (artificial or sun light, closed or open, intensified or not, higly axenic or not...), strain consortium culture, etc. Physiological optimisation aims to apply a physiological stress to the strain (N starvation, light intensity...) to make it accumulate specific molecules like lipids, proteins, pigments, sugars/EPS...