Production and partial characterization of arabinoxylan-degrading enzymes by Penicillium brasilianum under solid-state fermentation.
The production of a battery of arabinoxylan-degrading enzymes by the fungus Penicillium brasilianum grown on brewer's spent grain (BSG) under solid-state fermentation was investigated. Initial moisture content, initial pH, temperature, and nitrogen source content were optimized to achieve maximum production of feruloyl esterase, xylanase, and alpha-L: -arabinofuranosidase. Under the optimum growth conditions (80% moisture, pH 6, 26.5 degrees C, and 5 g/l nitrogen source), the maximum level of feruloyl esterase (1,542 mU/g BSG) was found after 196 h, whereas xylanase (709 U/g BSG) and ArabF activity (3,567 mU/g BSG) were maximal after 108 h and 96 h, respectively. Based on substrate utilization data, the feruloyl esterases produced by P. brasilianum was anticipated to subclass B. A crude enzyme (CE) preparation from P. brasilianum culture grown on BSG was tested for the release of hydroxycinnamic acids and pentoses from BSG. The P. brasilianum CE produced in this work contains a balance of cell wall-modifying enzymes capable of degrading arabinoxylan of BSG by more than 40%.
Center for Microbial Biotechnology, BioCentrum-DTU, Building 223, Technical University of Denmark, DK-2800, Kgs Lyngby, Denmark.
Gianni
G
Panagiotou
Pierre
P
Granouillet
Lisbeth
L
Olsson
D002265:Carboxylic Ester Hydrolases / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D003373:Coumaric Acids / Q000378:metabolism; D002523:Edible Grain / Q000378:metabolism; D043364:Endo-1,4-beta Xylanases / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D005285:Fermentation; D005612:Freeze Drying; D005656:Fungal Proteins / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D006813:Humidity; D006863:Hydrogen-Ion Concentration; D017672:Nitrogen Compounds / Q000378:metabolism; D010407:Penicillium / Q000201:enzymology* / Q000254:growth & development; D010429:Pentoses / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature; D013997:Time Factors; D014990:Xylans / Q000378:metabolism*
D003373:Coumaric Acids; D005656:Fungal Proteins; D017672:Nitrogen Compounds; D010429:Pentoses; D014990:Xylans; C085118:arabinoxylan; D002265:Carboxylic Ester Hydrolases; C070196:feruloyl esterase; D006026:Glycoside Hydrolases; C019713:alpha-N-arabinofuranosidase; D043364:Endo-1,4-beta Xylanases