Exploring the antioxidant effects of peptides from almond proteins using PAni-Ag-GONC conjugated trypsin by improving enzyme stability & applications

摘要

Functionalized graphene oxide nano-sheets (PAni-Ag-GONC) were prepared and employed as carrier for cova-lent immobilization of trypsin. This low cost setting, which involves loading of high amount of enzyme on the ma-trix, displayed significantly enhanced thermo-stability and pH resistance. The nano-composite (NC) bound trypsin preserved 90% of activity whereas native trypsin retained only 44% of activity after 60 days of storage at a temperature of 4 degrees C. Immobilized trypsin conserved 80.5% of activity even after its ten repeated uses. Almond protein hydrolysates prepared by native and conjugated enzyme was investigated for antioxidant activities and found that peptides resulted from NC bound trypsin displayed increase in radical scavenging activity (i.e. around 30% and 37% scavenging activity observed, respectively by native and NC bound trypsin from same concentration of peptides). This strategy provides a new approach for production of potential biopeptides which may be incor-porated in drugs and functional food industries applying PAni-Ag-GONC based biocatalysis. Chemical compounds: Trichloroacetic acid (PubChem CID: 6421); Tris (hydroxymethyl)aminomethane (PubChem CID: 6503); Glycine (PubChem CID: 750); and 2,2 '-diphenyl-1-picrylhydrazyl (PubChem CID: 74358); N alpha-Benzoyl-DL-arginine 4-nitroanilide hydrochloride (PubChem CID: 2724371); Ammonium sulphate (PubChem CID: 6097028). (C) 2020 Elsevier B.V. All rights reserved.