Production of amino acids by Azotobacter vinelandii and Azotobacter chroococcum with phenolic compounds as sole carbon source under diazotrophic and adiazotrophic conditions

Abstract

Azotobacter vinelandii strain ATCC 12837 and Azotobacter chroococcum strain H23 (CECT4435) were tested to grow in N-free or NH(4)Cl amended chemically defined media, with protocatechuic acid or sodium p-hydroxybenzoate as sole carbon (C) sources at a concentration of 2 mmol/L. Both substrates supported grow at similar rates than bacteria grown in control media amended with 2 mmol/L sodium succinate as C source. The two strains produced aspartic acid, serine, glutamic acid, glycine, hystidine, threonine, arginine, alanine, proline, cysteine, tyrosine, valine, methionine, lysine, isoleucine, leucine and phenylalanine after 72 h of growth in chemically defined media with 2 mmol/L of phenolic compounds or sodium succinate as sole C source amended or unamended with 0.1% (w/v) NH(4)Cl. Qualitative and quantitative production of all amino acids was not affected by the use of different C and N substrates.