Abstract: | The effect of oxidized and unoxidized oleic acid and Tween-80 on the growth and lysine synthesis by the producers C. glutamicum strains 95, 8, 28 was investigated. Surface active substances like oxidized and unoxidized oleic acid and Tween-80 during cultivation of the lysine producers on the glucose medium (the synthetic medium) and the medium with molasses and corn extract either inhibited the culture growth, thus reducing lysine yield, or accelerated the culture growth, thus increasing lysine yield. Oxidized and unoxidized oleic acid produced the greatest effect when added to the nutrient medium on the 48th cultivation hour. The increment of synthesized lysine was 120-150% of the control. Tween-80 proved to be very effective when added at early stages of fermentation (20 hours). |