Improvement of fed batch mass culture for g linolenic biosynthesis by Tetrahymena rostrata (Protozoa).

Despite' the general high sensitivity of protozoa to shearing effects, Tetrahymena rostrata was cultivated using a controlled fed batch fermentor; the feeding medium contained 15 % skimmed milk. With an unchanged growth rate, final cell concentration (14.105 cell/ml) was 4 times higher than in simple batch culture. gamma-Linolenic acid (16 % of the total fatty acids) reached 0.5 gr/l medium.