Bioconversion of Agave Bagasse to Produce Cellulases and Xylanases by Penicillium citrinum and Aspergillus fumigatus in Solid-State Fermentation

Abstract

In Mexico, the generation of agave bagasse (AB) has increased considerably in recent years, given the growing global demand for tequila and other products from agave plants; around 45 thousand tons of AB are produced monthly only from tequila production. Despite the potential of AB to produce high-value metabolites, its use is limited. Several efforts have been made to mitigate the environmental problem caused by the final disposition of AB; however, the use of AB to produce enzymes has not been widely explored. This work presents a comparative analysis of the bioconversion of AB by Aspergillus fumigatus and Penicillium citrinum to produce cellulases and xylanases by solid-state fermentation, using wheat straw (WS) and sugarcane bagasse (SCB) as control feedstocks. The highest cellulase productions were obtained on AB with 10,112 and 7,347 U/kg of AB by P. citrinum and A. fumigatus, respectively. Regarding the xylanase production, the best producer was A. fumigatus (125,250 U/kg of WS), while the maximum xylanase production on AB was 28,974 U/kg of AB by P. citrinum. These results show the promising potential of AB to produce lignocellulase enzymes and open the vision towards implementing a circular economy strategy around the agave plant transformation.