Location: Bioenergy ResearchTitle: Phosphate limitation alleviates the inhibitory effect of manganese on itaconic acid production by Aspergillus terreus
Submitted to: Biocatalysis and Agricultural Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/28/2019
Publication Date: 1/31/2019
Citation: Saha, B.C., Kennedy, G.J. 2019. Phosphate limitation alleviates the inhibitory effect of manganese on itaconic acid production by Aspergillus terreus. Biocatalysis and Agricultural Biotechnology. 18:101016. https://doi.org/10.1016/j.bcab.2019.01.054.
Interpretive Summary: Itaconic acid is a building block platform chemical which is produced industrially from glucose by fermentation with a fungus. Biomass has the potential to serve as low cost source of sugars for itaconic acid production. However, the fungus could not produce itaconic acid from hydrolyzed biomass. Among other factors, one metal ion was found to severely inhibit the itaconic acid production. In this work, the interactions of this metal ion with medium components for itaconic acid production were investigated. Limitation of one medium component greatly alleviates the inhibitory effect of the metal ion on itaconic acid production by the fungus. The results will be very useful in developing process technology for itaconic acid production from biomass by the fungus.
Technical Abstract: Lignocellulosic biomass has the potential to serve as a low cost source of sugars for production of itaconic acid (IA, a building block platform chemical) by fermentation with Aspergillus terreus. However, the IA production from biomass hydrolysate was severely inhibited. Mn2+ was found to inhibit the IA production. The effect of Mn2+ on each medium component (KH2PO4, NH4NO3, MgSO4·7H2O, CaCl2·2H2O, FeCl3·6H2O, ZnSO4·7H2O, and CuSO4·7H2O) was evaluated for sugar utilization and IA production by A. terreus NRRL 1972. Both potassium and phosphate were necessary for IA production. Low PO4 in the medium greatly alleviated the inhibitory effect of Mn2+ on IA production. However, high PO4 (not K) was detrimental for IA production in the presence of Mn2+. The inhibitory effect of Mn2+ on IA production was partly eliminated by increasing the CuSO4 level in the medium. This is the first study on the relationship of Mn2+ on the medium components for utilization of sugar and production of IA.