Abstract
Itaconic acid is an industrial produced chemical by the sensitive filamentous fungus Aspergillus terreus and can replace petrochemical-based monomers for polymer industry. To produce itaconic acid with alternative renewable substrates, such as lignocellulosic based hydrolysates, a robust microorganism is needed due to varying compositions and impurities. Itaconic acid producing basidiomycetous yeasts of the family Ustilaginaceae provide this required characteristic and the species Ustilago rabenhorstiana was examined in this study. By an optimization of media components, process parameters, and a fed-batch mode with glucose the final titer increased from maximum 33.3 g·L−1 in shake flasks to 50.3 g·L−1 in a bioreactor. Moreover, itaconic acid was produced from different sugar monomers based on renewable feedstocks by U. rabenhorstiana and the robustness against weak acids as sugar degradation products was confirmed. Based on these findings, U. rabenhorstiana has a high potential as alternative natural itaconic acid producer besides the well-known U. maydis and A. terreus.
Highlights
Itaconic acid is an interesting chemical for the polymer industry, which is produced in a biotechnological process based on renewable substrates [1]
This study considers the cultivation of Ustilago rabenhorstiana for itaconic acid production and its potential as alternative natural producer
This study describes a known, but so far unspecified, itaconic acid producer—U. rabenhorstiana
Summary
Itaconic acid is an interesting chemical for the polymer industry, which is produced in a biotechnological process based on renewable substrates [1]. Since the 1960s, the filamentous fungus Aspergillus terreus is industrially used with a titer of. A. terreus achieves a productivity up to 1.15 g (L·h)−1 and a yield of 0.64 (w/w), whereby the theoretical yield with glucose is 0.72 (w/w) [7,8]. Itaconic acid was successfully produced by A. terreus with glycerol, starch hydrolysates, molasses, and different monosaccharides, like xylose, arabinose, galactose, and rhamnose [10]. A great cultivation challenge is caused by sugar degradation products or other impurities in lignocellulosic hydrolysates, which influence the morphology and itaconic acid production of the fungus. Due to the sensitivity of the fungus, complex purification processes are used for such hydrolysates or more resistant strains are generated by mutagenesis [11,12,13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
