Production of itaconic acid by Pseudozyma antarctica NRRL Y-7808 under nitrogen-limited growth conditions

Pseudozyma antarctica NRRL Y-7808 was found to produce itaconic acid from glucose and other sugars under nitrogen-limited growth conditions. Other Pseudozyma strains screened, including a second strain of P. antarctica, did not produce this product; therefore itaconic acid production is not a common trait of the genus. Glucose and fructose were the most efficiently utilized substrates, followed by sucrose and maltose; lactose and glycerol were the poorest substrates. The maximum yield in flask experiments was 37.5% (approximately 30 g/L itaconic acid from 80 g/L glucose). The maximum rate of production in flask cultures was 248 mg L−1 h−1 at a C/N ratio of 116, while the best combination of rate and yield was produced at a C/N ratio of 175 (230 mg L−1 h−1 and 29%, respectively). A stirred-tank reactor process study resulted in a 20% yield and volumetric production rate of 110 mg L−1 h−1.