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

[Display omitted] •A sustainable and cheap process was defined for GA3 production in bioreactors.•Citric pulp and soybean hulls were studied as new substrates for GA3 production.•GA3 clarification carried out for the first-time using membrane technology.•GA3 liquid and powder stable formulations were obtained.•Alginate and kefiran were used for GA3 encapsulation for future controlled release. The aim of this work was to develop a new production, recovery and formulation process of gibberellic acid (GA3). Low-cost byproducts – citrus pulp (CP) and soybean hulls (SH) – were employed as substrate for GA3 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). GA3 production medium cost (US$ 6.70/m3) was reduced by 85% when compared to previously reported synthetic media (US$ 44.96/m3). It was described that GA3 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 GA3 showed encapsulation efficiency of 70% and 60%, respectively. This work supports good perspectives for GA3 production using cheap substrates and simple formulation of clarified extract to favour its use in agricultural countries.