Itaconic acid production by Aspergillus terreus from low-cost carbon and nitrogen sources

taconic acid (IA) is a biobased building block of great interest for polymer of thermoplastic, resin, chelating agents, superabsorbent polymers (SAP), among many others. This study evaluated IA production by Aspergillus terreus with low-cost carbon – granulated sugar and VHP (very high polymerization) sugar – and nitrogen sources – ammonium nitrate and commercial urea. The highest final IA concentration was obtained with the combination of granulated sugar and NH4NO3 (40 g/L IA), while the fermentation of VHP sugar and NH4NO3 produced 25 g/L IA. The use of commercial urea resulted on low IA titers (about 8 g/L IA) with either granulated sugar or VHP sugar. Despite achievement of the highest values of IA production in granulated sugar medium, the lower cost of VHP motivated the evaluation of two different inoculum methods preparation to improve IA (spores and mycelia). The inoculum with mycelia resulted in 45 g/L IA, equivalent to the value obtained with granulated sugar inoculated with spores. Moreover, the productivity was over 3 times higher with mycelia instead of with spores (respectively 0.19 and 0.06 g/L/h). The yield of IA from the fermentation of VHP and NH4NO3 inoculated with mycelium was 53% of the theoretical. This study demonstrates the potential of VHP sugar as carbon source for IA production, which may be applied in a biorefinery concept.