MIXOTROPHIC PRODUCTIVITY OF THE MARINE DIATOM PHAEODACTYLUM-TRICORNUTUM CULTURED WITH SOLUBLE FRACTIONS OF RYE, WHEAT AND POTATO

The marine microalga Phaeodactylum tricornutum was cultured semi-conti nuously with the soluble fractions of wheat, rye and boiled potato flo urs. Fifteen percent of the culture volume was renewed every 3 d. The cell productivities were 0.9 x 10(9) cells/l/d, 1.1 x 10(9) cells/l/d and 2.6 x 10(9) cells/l/d for wheat, rye and potato respectively. The productivity of the autotrophic control was 1.0 x 10(9) cell/l/d. When a soluble fraction of raw potato was added, the productivity was enha nced to 4.1 x 10(9) cells/l/d, 2.4 times higher than the autotrophic c ulture. The high productivity of P. tricornutum with the soluble fract ions of Solanum tuberosum suggests its usefulness as a source of nutri ents for the production of microalgal biomass.