Analysis and modeling of the ferulic acid oxidation by a glucose oxidase-peroxidase association. Comparison with a hexose oxidase-peroxidase association.
A commercial glucose oxidase (GOX) from Aspergillus niger was partially characterized. The enzyme exhibited a two-step transfer mechanism, and the kinetic constants toward glucose and oxygen were determined. Under conditions similar to dough making (glucose concentration and pH), GOX does not exhibit maximum activity. A hexose oxidase (HOX) from Chondrus crispus was partially characterized as well. The HOX activity is not far from the optimum in the kneading conditions (pH and glucose concentration). A peroxidase (POD) purified from wheat germ was used to oxidize ferulic acid in the presence of GOX or HOX. Hydrogen peroxide produced during the glucose oxidation activates the wheat germ POD. Ferulic acid oxidation in solutions containing different ratios of POD + GOX or HOX + POD was followed by UV spectrophotometry. For the same dosage, the HOX-POD system is the most efficient for peroxidase activation. Using absorbance data and kinetic constants of GOX and POD, a mathematical model describing the release or consumption of the different reactants (hydrogen peroxide, oxygen, and ferulic acid) in the medium was developed, and experimental data correlated well with calculated values. The results obtained will be applied to investigate the effect of GOX and HOX activities on the rheological properties of dough.
Garcia
Rebeca
R
Chaire de biochimie industrielle et agro-alimentaire, UMR SCALE 1211 (ENSIA/CNAM/INRA), Conservatoire National des Arts et Métiers, 292 Rue Saint-Martin, 75141 Paris 3, France.
Rakotozafy
Lalatiana
L
Nicolas
Jacques
J
D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D001234:Aspergillus niger / Q000201:enzymology; D044723:Chondrus / Q000201:enzymology; D003373:Coumaric Acids / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D005949:Glucose Oxidase / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010100:Oxygen / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism*; D014908:Triticum / Q000201:enzymology
D003373:Coumaric Acids; C004999:ferulic acid; D006861:Hydrogen Peroxide; D000429:Alcohol Oxidoreductases; D005949:Glucose Oxidase; C021354:hexose oxidase; D009195:Peroxidase; D005947:Glucose; D010100:Oxygen