Process for the preparation of L-proline by cultivating algae

A process for the production of L-proline which comprises cultivating Chlorella sp. 580 algae under high-intensity illumination in an aqueous growth medium containing an amount sufficient of nutrients including nitrogen to effect growth of the algae in a sodium chloride concentration of up to 0.5 M under an aerobic condition, providing an adequate supply of carbon in a depth not exceeding approximately 20 cm of the aqueous medium for a period of time sufficient for the algae to obtain a cell density of up to at least 5 g/l and thereafter increasing the sodium chloride concentration in the medium to 1 molar and continuing cultivating the algae until algae of high L-proline content are obtained, harvesting the algae and recovering from same the L-proline thus produced.