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Itaconic acid (IA), a building block platform chemical, is produced industrially by Aspergillus terreus utilizing glucose. Lignocellulosic biomass can serve as a low cost source of sugars for IA production. However, the fungus could not produce IA from dilute acid pretreated and enzymatically saccharified wheat straw hydrolyzate even at 100‐fold dilution. Furfural, hydroxymethyl furfural and acetic acid were inhibitory, as is typical, but Mn2+ was particularly problematic for IA production. It was present in the hydrolyzate at a level that was 230 times over the inhibitory limit (50 ppb). Recently, it was found that PO43− limitation decreased the inhibitory effect of Mn2+ on IA production. In the present study, a novel medium was developed for production of IA by varying PO43−, Fe3+ and Cu2+ concentrations using response surface methodology, which alleviated the strong inhibitory effect of Mn2+. The new medium contained 0.08 g KH2PO4, 3 g NH4NO3, 1 g MgSO4·7H2O, 5 g CaCl2·2 H2O, 0.83 mg FeCl3·6H2O, 8 mg ZnSO4·7H2O, and 45 mg CuSO4·5H2O per liter. The fungus was able to produce IA very well in the presence of Mn2+ up to 100 ppm in the medium. This medium will be extremely useful for IA production in the presence of Mn2+. This is the first report on the development of Mn2+ tolerant medium for IA production by A. terreus. [ABSTRACT FROM AUTHOR]

Itaconic acid (IA), an unsaturated 5-carbon dicarboxylic acid, is a building block platform chemical that is currently produced industrially from glucose by fermentation with Aspergillus terreus. However, lignocellulosic biomass has potential to serve as low-cost source of sugars for production of IA. Research needs to be performed to find a suitable A. terreus strain that can use lignocellulose-derived pentose sugars and produce IA. One hundred A. terreus strains were evaluated for the first time for production of IA from xylose and arabinose. Twenty strains showed good production of IA from the sugars. Among these, six strains (NRRL strains 1960, 1961, 1962, 1972, 66125, and DSM 23081) were selected for further study. One of these strains NRRL 1961 produced 49.8 ± 0.3, 38.9 ± 0.8, 34.8 ± 0.9, and 33.2 ± 2.4 g IA from 80 g glucose, xylose, arabinose and their mixture (1:1:1), respectively, per L at initial pH 3.1 and 33°C. This is the first report on the production of IA from arabinose and mixed sugar of glucose, xylose, and arabinose by A. terreus. The results presented in the article will be very useful in developing a process technology for production of IA from lignocellulosic feedstocks. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1059-1067, 2017 [ABSTRACT FROM AUTHOR]

Biological pretreatment of lignocellulosic biomass by white-rot fungus can represent a low-cost and eco-friendly alternative to harsh physical, chemical, or physico-chemical pretreatment methods to facilitate enzymatic hydrolysis. In this work, solid-state cultivation of corn stover with Phlebia brevispora NRRL-13018 was optimized with respect to duration, moisture content and inoculum size. Changes in composition of pretreated corn stover and its susceptibility to enzymatic hydrolysis were analyzed. About 84% moisture and 42 days incubation at 28°C were found to be optimal for pretreatment with respect to enzymatic saccharification. Inoculum size had little effect compared to moisture level. Ergosterol data shows continued growth of the fungus studied up to 57 days. No furfural and hydroxymethyl furfural were produced. The total sugar yield was 442 ± 5 mg/g of pretreated corn stover. About 36 ± 0.6 g ethanol was produced from 150 g pretreated stover per L by fed-batch simultaneous saccharification and fermentation (SSF) using mixed sugar utilizing ethanologenic recombinant Eschericia coli FBR5 strain. The ethanol yields were 32.0 ± 0.2 and 38.0 ± 0.2 g from 200 g pretreated corn stover per L by fed-batch SSF using Saccharomyces cerevisiae D5A and xylose utilizing recombinant S. cerevisiae YRH400 strain, respectively. This research demonstrates that P. brevispora NRRL-13018 has potential to be used for biological pretreatment of lignocellulosic biomass. This is the first report on the production of ethanol from P. brevispora pretreated corn stover. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:365-374, 2017 [ABSTRACT FROM AUTHOR]