Nutritional and physical fermentation conditions are considerable factors for gibberellic acid production by Fusarium moniliforme. Four strains were investigated to produce gibberellic acid, i.e. fermentation process was carried out on three media to select the better one, different concentrations of sucrose, different nitrogen sources, pH levels, temperature range, inoculum size and fermentation period. Also, the effect of gibberellic acid concentrations on Saccharomyces (bakers' yeast) was also studied.
Results indicate that Czapek's medium was the best for gibberellic acid production by Fusarium moniliforme (F3) and (F1). Fusarium moniliforme (F3) was found to be superior in gibberellic acid production than the strain (F1).
The maximum yield of gibberellic acid was obtained in the presence of 40 g/L sucrose, NH4Cl as a nitrogen source, 2% (v/v) inoculum size, incubation temperature of 25°C, pH 5.5 and 12 days fermentation period.
Results also show that 10 ppm of gibberellic acid is the most effective concentration in increasing the growth of Saccharomyces.