Extractive fermentation of gibberellic acid production by free and immobilized Gibberella fujikuroi fungi

In this study, extractive gibberellic acid production was investigated using free and immobilized Gibberella fujikuroi fungi. Firstly, the effect of fermentation time and substrat concentration on gibberellic acid production using Gibberella fujikuroi fungi were examined. Then, extractive gibberellic acid production was investigated. Octanol and Alamine 336 were used as organic phase in the extractive fermentation experiments. Solvent toxicity was tried to prevent by using oleyl alcohol as diluent and adding corn oil and immobilized Gibberella fujikuroi fungi to the fermentation medium. Optimum organic phase concentration was obtained as %15 (v/v) Alamine 336 in oleyl alcohol. The highest gibberellic acid concentration (158.9 mg/L) was obtained using immobilized microorganism and adding of 5 % corn oil to the fermentation media and with air feeding conditions. Gibberellic acid concentration was increased 2.6 times with respect to the control .