Characterization of the Biodegradation Properties of Lignocellulosic Material by Pichia Kudriavzevii Isolated From Cocoa Pod Shell (Theobroma Cacao)

Abstract Utilizing residual lignocellulosic biomass as a raw material for producing various commercially valuable products offers an alternative approach to mitigating the environmental pollution stemming from agro-industrial waste. In this study, a native microbial isolate obtained from the shell of cocoa pod, utilized in silage processes, underwent phenotypic characterization. Taxonomic identification through sequencing of the Internal Transcribed Spacer (ITS) region, specifically ITS4 and ITS5, revealed that the isolate corresponded to the yeast Pichia kudriavzevii. Through qualitative and quantitative screening of lignocellulolytic enzymes, the yeast's capacity for the production of endo- and exo-cellulases, lignin peroxidases, and xylanases was determined. Biodegradation tests of the cocoa pod shell were carried out during a laboratory-scale silage process. In these assays, the degrading capacity of the microorganism in solution was evaluated in comparison to a commercial inoculum and an enzymatic extract of the same yeast. The results of these tests showed that the cocoa pod shell was degraded in different proportions, finding degradation values for lignin, cellulose and hemicellulose of 11%, 18% and 37%, respectively. Pichia kudriavzevii showed an important capacity to contribute to the degradation of the cocoa pod shell.