Abstract: According to the invention there is provided a process for the simultaneous production of glycerol, carotenes(.beta.-carotene, its isomers and carotene-like substances) and protein rich material which comprises cultivating algae of the Dunaliella bardawil species under high-intensity illumination in a growth medium containing a high concentration of sodium chloride (at least 1,5 M in the final stage of the cultivation), providing an adequate supply of carbon, in a depth of not exceeding 20 cm of the aqueous medium, in a diurnal cycle of illumination, until algae of high content of the above three components are obtained, harvesting the algae and recovering from same the three constituents.

Abstract: A process for the production of glycerol and proteinous substances of nutritive value which comprises cultivating algae of the Dunaliella species in a nutrient medium containing the mineral requirements of growth of the algae, said nutrient medium having a sodium chloride content of at least 1.5 M, the cultivation being effected while an adequate supply of carbon dioxide is provided and continued until a maximum concentration of algae is obtained, and continuing the cultivation of the algae in a nutrient medium having a content of sodium chloride of at least 3 M, cultivating the algae in this second nutrient medium until a high glycerol content is established, harvesting the algae, recovering from same the glycerol, and recovering the residue having a high protein content.

Abstract: An alga named Dunaliella bardawil is similar to D. salina except that its length is 15-19 .mu.m, its diameter 10-14 .mu.m and its volume 200-1000 .mu.m.sup.3, and it contains large quantities of carotene and glycerol.