Patent ID: 6878534

Claim:
A continuous fermentation process for the production of propionic acid and vitamin B 12 , which comprises: culturing a strain of Propionibacterium for producing propionic acid and vitamin B 12 , wherein said culturing occurs in at least two successive fermentors, said fermentors comprising a first fermentor for producing propionic acid comprising a culture medium for producing propionic acid, wherein said strain of Propionibacterium is cultured under anaerobic conditions at a temperature of about 37° C. and a pH of about 6.5, and wherein said propionic acid is recovered from said first fermentor, and a second successive, continuous fermentor for producing vitamin B 12 comprising a culture medium for producing vitamin B 12 and further comprising an amount of said culture medium from said first fermentor sufficient to inoculate said second fermentor, wherein said strain of Propionibacterium is cultured, in the presence of propionic acid, under aerobic conditions at a temperature of about 42° C. and a pH of about 6.5 and wherein vitamin B 12 is recovered from said second fermentor, and provided that said culture medium for producing propionic acid and said culture medium for producing vitamin B 12 further comprise 5,6-dimethylbenzimidazole, when said strain of Propionibacterium is Propionibacterium acidipropionici.