EN
Propionibacterium freudenreichii subsp. shermanii 1 and 4 were immobilized in the living state in 2, 3 and 4% alginate gels, in 2, 4 and 6% carrageenan gels, in 2, 4 and 6% carrageenan/locust bean gum gels and on ceramic support. Ammonia consumption, glucose utilization, production of propionic and acetic acids, biosynthesis of vitamin B12 and cell release rate were examined. A significant increase of productivity of propionic acid and decrease of biosynthesis of vitamin B12 using immobilized cells were observed. The best results were obtained in the fermentation with strains immobilized in 4% alginate gel, when applied for the third time. In this case, production of propionic acid was 50% higher in comparison with free cells and biosynthesis of vitamin B12 was lower or the same as in the control.