Secretomic Analysis of Aspergillus niger and Phanerochaete carnosa Cultured on Corn Bran Fiber under Submerged Fermentation

Abstract

In order to produce enzyme cocktails with an advantage in hemicellulose degradation for enzymatic hydrolysis of corn bran fiber (CBF) to produce oligoarabinoxylan, Aspergillus niger and Phanerochaete carnosa were cultured on CBF (containing 50.97% xylose and 28.47% arabinose) under submerged fermentation. The maximum xylanase activity of A. niger and P. carnosa during fermentation was found to be 246.58 (72 h) and 367.21 U/mL (60 h), and the highest activity of α-L-arabinofuranosidase of A. niger and P. carnosa was 57.90 (144 h) and 8.26 U/mL (192 h), respectively. Label-free proteomic analysis revealed that a total of 109 and 105 proteins were identified from the fermentation broths of P. carnosa and A. niger, respectively. The number of glycoside hydrolases secreted by A. niger (82) was more than that produced by P. carnosa (53), and there was also a great difference in the distribution of the glycoside hydrolase family between the two strains, while the number of oxidases secreted by P. carnosa (6) was higher than that secreted by A. niger (2). The results showed that A. niger and P. carnosa could grow on CBF as a carbon source and secrete enzyme cocktails with different compositions but similar catalytic function and efficiency, suggesting that A. niger and P. carnosa use different multi-enzyme synergetic strategies to degrade CBF.

Keywords

• corn bran fiber; aspergillus niger; phanerochaete carnosa; secretomics; fermentation