Production of Astaxanthin and 4-Ketozeaxanthin by the Marine Bacterium, Agrobacterium aurantiacum.

In attempts to find new sources of astaxanthin, approximately 200 strains of marine bacteria were collected from the sea near Okinawa Islands for screening. Silica gel TLC, VIS, EIMS, H-1-NMR, CD, and optical resolution HPLC data indicated that one of the strains, Agrobacterium aurantiacum, produced (3S,3'S)-astaxanthin and (3S,3'R)-4-ketozeaxanthin.