Cell Growth and Metabolites Produced by Fluorescent Pseudomonad R62 in Modified Chemically Defined Medium

Chemically defined Schlegel-s medium was modified to improve production of cell growth and other metabolites that are produced by fluorescent pseudomonad R62 strain. The modified medium does not require pH control as pH changes are kept within ± 0.2 units of the initial pH 7.1 during fermentation. The siderophore production was optimized for the fluorescent pseudomonad strain in the modified medium containing 1% glycerol as a major carbon source supplemented with 0.05% succinic acid and 0.5% Ltryptophan. Indole-3 acetic acid (IAA) production was higher when L-tryptophan was used at 0.5%. The 2,4- diacetylphloroglucinol (DAPG) was higher with amended three trace elements in medium. The optimized medium produced 2.28 g/l of dry cell mass and 900 mg/l of siderophore at the end of 36 h cultivation, while the production levels of IAA and DAPG were 65 mg/l and 81 mg/l respectively at the end of 48 h cultivation.

Authors:

• K. Saharan
• M.V. R. K. Sarma
• A. S. Roesti
• A. Prakash
• B. N. Johri
• M. Aragno
• V. S. Bisaria
• V. Sahai

Keywords:

• Fluorescent pseudomonad
• Fermentation
• Metabolites production
• PGPR.

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