A flexible culture process for production of the green microalga Scenedesmus dimorphus rich in protein, carbohydrate or lipid

Microalgae have the ability to undergo programmatic changes in photosynthetic carbon partitioning and thus cellular biochemical composition, particularly in the relative amounts of crude protein, lipids, and carbohydrate, in response to changes in environmental and culture conditions. In this study, a novel strategy that employs a single microalgal strain Scenedesmus dimorphus grown in a single cultivation platform to produce protein-, carbohydrate- or lipid-rich biomass, as so desired, was introduced. With the combined manipulation of nitrogen availability and light intensity and cell inoculation density, it was successfully demonstrated that highest yields for protein and carbohydrate were 0.2 and 0.7 g L−1 d−1, respectively, which could be obtained in early stages of cultivation, while the highest yield for lipid, 0.17 g L−1 d−1, occured in a late stage of cultivation.