Comparative Evaluation of Chlorella v-ulgaris and Chlorella sorokiniana for Food Related Applications

Abstract Microalgae can be sought as a green source of valuable nutrients. Several Chlorella species belong to the edible species according to regulations. Commercial food supplements are made mainly of C. vulgaris whereas C. sorokiniana has been mostly examined as a source of biofuels. This study aimed to investigate the composition of C. sorokiniana cultivated in semi-pilot scale in comparison to commercially available C. vulgaris with a focus on human nutrition. To this end, the composition in macronutrients, the fatty acid profile of the lipid fraction, the amino acid profile of the protein fraction, and the antioxidant activity of the hydrophilic and hydrophobic fraction of the biomass were determined. Furthermore, and to explore the potential application of the microalgae as a lipid source for food related applications, special focus was given to lipid extraction. The effects of cell disruption and of different scalable extraction methods using different food-grade solvents were examined. A high protein concentration (44–48%) and high concentration in essential amino acids was found for both microalgae. Moreover, the lipids of both microalgae were rich in polyunsaturated fatty acids (PUFAs) whereas of C. sorokiniana was rich in omega-3 fatty acids and C. vulgaris in omega-6 fatty acids. In addition, the hydrophilic and hydrophobic fraction of microalgae presented high antioxidant activity. Regarding the methods for lipids extraction, the combination of solvents with different polarity and the use of disrupted biomass cells resulted in the highest lipids recovery reaching 89% for C. sorokiniana . Graphical Abstract