Development of a cost-effective medium for submerged production of fungal aryl alcohol oxidase using a genetically modified Aspergillus nidulans strain. (June 2020)

• Record Type: Journal Article
• Authors: Liu, Enshi; Li, Mengxing; Abdella, Asmaa; Wilkins, Mark R.
• Is Part Of: Bioresource technology. Volume 305(2020)
• Publication Date: 2020-06
• Subjects: Lignin-degrading enzymes -- Filamentous fungi -- Enzyme production -- Submerged fermentation -- Medium development; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2020.123038
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Cost-effective medium for AAO production by Aspergillus nidulans was developed. Corn steep liquor provided sufficient nutrients for enzyme production. Medium components were optimized and validated. Greatest aryl alcohol oxidase activity (1021 U/L) was achieved. Protein concentration reached 0.75 g/L. Abstract: Aryl alcohol oxidase (AAO), an extracellular H2 O2 -providing enzyme, plays a central role in lignin depolymerization. Cost-effective production of AAO has not been achieved, due to the low yield of enzyme-producing microorganisms and the high cost of fermentation media. This study aims to develop a cost-effective medium for high-yield production of AAO in submerged culture using a recombinant Aspergillus nidulans strain. Results demonstrate that corn steep liquor (CSL) was a rich but inexpensive nitrogen source for AAO production, and CSL can provide enough trace metals and vitamins (i.e. pyridoxine) for A. nidulans . A 2-level Plackett-Burman design was utilized to determine the main affecting factors in AAO production. The medium was further optimized by a 3-level Box-Behnken design to obtain the optimum medium component concentrations (61.0 g/L maltose, 26.4 g/L CSL, and 13.8 g/L NaNO3 ). The greatest AAO activity achieved was 1021 U/L with a protein concentration of 0.75 g/L.