Cellulase production from disposed COVID-19 personal protective equipment (PPE) using cyclic fed-batch strategies

ABSTRACT

Wild fungal strain-employing, cellulase production bio-processes require 17-fold higher quantities of lignocelluloses than biofuel production. Globally-available, conventional lignocelluloses are 3 × 103-fold lesser than their requirement for bio-alcohol-fossil fuel blending purposes. In an attempt to explore biomass alternatives, demonstrate their potential in cellulase production, and to simultaneously-address process-deterring conditions of solid-state and submerged fermentations, cellulose-rich, COVID-19 personal protective equipment-based substrates were used in time-extended, empirical data-driven, optimal condition-maintaining cyclic fed-batch strategies. While 37% and 43% increases of cumulative cellulase yields were recorded for solid and submerged cyclic operations, respectively, they were 21% and 28% more economical than multiple, individual batches. Furthermore, the operations improved kinetics of fungal growth, oxygen transfer, nutrient utilization, and maintained optimal parameter balance between variables, thereby improving consistency in cellulase titers. Apart from being sustainable, the demonstration suggests a recycle route for managing such health hazard-posing wastes, in turn alleviating environmental pollution and earning carbon credits.