摘要 |
Process for the production of 6-hydroxynicotinic acid by biotechnological methods. Nicotinic acid is enzymatically hydroxylated in the presence of equivalent quantities of magnesium or barium ions with the help of nicotinic acid-hydroxylating microorganisms. The resultant magnesium or barium salt of the 6-hydroxynicotinic acid is separated from the reaction mixture. Then the 6-hydroxynicotinic acid is freed from the separated salts. Examples of the microorganism are the species Pseudomonas, Bacillus or Achromobacter, for example, Achromobacter xylosoxydans. Preferably the enzymatic hydroxylation is carried out at 20 DEG to 40 DEG C. and a pH of 5.5 to 9.0 under aerobic conditions.
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