Improved development in magnetic Xyl-CLEAs technology for biotransformation of agro-industrial by-products through the use of a novel macromolecular cross-linker

Abstract

Cross-Linked Enzyme Aggregates (CLEAs) technologies for enzyme immobilization are influenced by mass transference problems as the degree of molecular crosslinking achieved strongly affects the enzyme exposure to the substrates. Therefore, this work seeks to improve the accessibility of high molecular weight substrates by using macromolecular cross-linkers to the synthesis of a xylanolytic biocatalyst. After confirming that commercial polymers used as macromolecular cross-linkers significantly upgraded the xylanase activity from a crude preparation, a novel biopolymer/amyloid protein complex (BPAP) extracted from a microbial biofilm was used producing a remarkable recovery (83%) of the enzyme activity.A response surface methodology was applied to contrast the features of a previously developed biocatalyst with glutaraldehyde (GA@Xyl-CLEAs) and a novel one synthesized with BPAP combined with functionalized magnetic nanoparticles: mBPAP@Xyl-CLEAs. It was observed that the crosslinking agent used was the factor that most affected the enzyme activity. Also, the mBPAP system showed a similar and higher hydrolytic activity than those synthesized with GA, which was not affected by the mNPs/protein ratio. Finally, the mBPAP@Xyl-CLEAs were successfully tested for xylooligosaccharides production from agroindustrial-derived substrates, making this technology a promising practice to obtain green and suitable biocatalysts.