Potential antioxidant activity of multienzymatically hydrolyzed corncob

Agroindustrial waste can be seized through enzymatic bioprocesses, replacing chemical processes, and obtaining added-value products. This work aimed to use an immobilized multienzyme composite to hydrolyze corn cob, resulting in a potential nutraceutical product with antioxidant activity. Chitosan-coated nanoparticles were synthesized by in situ alkaline co-precipitation and retained 14.7 ± 0.15 μg of soluble protein per mg of magnetic composite. Aglomerates within the size range of 102 ± 99.1, 762 ± 296, and 726 ± 194 nm of individual FeO nanoparticles (~25 nm) were observed in FeO nanoparticles, FeO@Chitosan, and FeO@Chitosan@Enzymes by transmission electron mycroscopy. Raman spectrogram showed a possible crosslinking between the magnetic composite and the enzymes. A 2 full factorial with one central point experimental design with temperatures of 50–70 °C and pH 4–7 was used to maximize the corncob hydrolysis using the catalytic composite. Statistical analysis showed maximum hydrolysis at pH 4 and 50 °C. Then, six reaction cycles of 1 h were achieved before the relative activity of the composite reached 50% of its initial value. The hydrolyzed corncob showed a 4.19-fold increase in flavonoids content, while antioxidant activity of DPPH and ABTS increased 6.52- and 18.2- fold, therefore 200 mL of hydrolyzate could meet the required daily human uptake of flavonoids. Multienzymes immobilized on magnetic composites using natural crosslinkers for hydrolysis of corn cob produce a potential nutraceutical product with antioxidant activity. Graphical abstract: [Figure not available: see fulltext.]