Improved thermostable polyvinyl alcohol electrospun nanofibers with entangled naringinase used in a novel mini-packed bed reactor

Improved NGase–PVA electrospun nanofibers. [Display omitted] •Development of PVA non-crosslinked electrospun nanofibers.•PVA electrospun nanofibers crosslinked with boronic acids displayed high thermal stability.•Optimized naringin hydrolysis by naringinase entrapped in PVA electrospun naofibers.•Development of a mini-PBR used with NGase PVA electrospun nanofibers.•A scaled down approach to identify and optimize operational conditions was developed. Polyvinyl alcohol (PVA) electrospun nanofibers were produced using an electrospinning technique. Key parameters (e.g. collectors, distance from needle tip to collector, among others) that influence the structure and morphology of fibers were optimized. The naringinase entrapped in PVA nanofibers retained over 100% of its initial activity after 212h of operation, at 25°C. Chemical crosslinking with several boronic acids further increased the hydrolysis temperature (up to 85°C) and yielded nanofibers with thermal stability up to 121°C. A mini packed bed reactor (PBR) developed to establish the feasibility for continuous enzymatic operation, ran for 16days at 45°C. Highest naringenin biosynthesis was attained at a flow rate of 10mLh−1. Highest volumetric (78molL−1h−1) and specific (26molh−1genzyme−1) productivities were attained at 30mLh−1. The activity of NGase in electrospun nanofibers remained constant for almost 16days of operation at 10mLh−1.