Alternative methods for gibberellic acid production, recovery and formulation: A case study for product cost reduction.

The aim of this work was to develop a new production, recovery and formulation process of gibberellic acid (GA). Low-cost byproducts - citrus pulp (CP) and soybean hulls (SH) - were employed as substrate for GA production by Gibberella fujikuroi in semisolid fermentation. A CP/SH mixture (70%/30%) promoted high productivities both in bubble column reactor (1.66 mg L/h), and in stirred tank reactor (2.13 mg L/h). GA production medium cost (US$ 6.70/m) was reduced by 85% when compared to previously reported synthetic media (US$ 44.96/m). It was described that GA fermented extract has low stability, and that liquid and powder formulation of the fermented extract maintained the biomolecule activity over 6 months. Alginate and alginate/kefiran beads containing GA showed encapsulation efficiency of 70% and 60%, respectively. This work supports good perspectives for GA production using cheap substrates and simple formulation of clarified extract to favour its use in agricultural countries.