Cost-effective lignocellulolytic enzyme production by Trichoderma reesei on a cane molasses medium

Abstract

Background: Cane molasses, an important residue of the sugar industry, have the potential as a cost-effective carbon source that could serve as nutrients for industrial enzyme-producing microorganisms, especially filamentous fungi. However, the enzyme mixtures produced in such a complex medium are poorly characterized. In this study, the secretome of Trichoderma reesei grown on a cane molasses medium (CMM) as well as on a lactose-based conventional medium (LCM) were compared and analyzed by using proteomics. Results: In this study we show that both the CMM and LCM can serve as excellent growth media for T. reesei. The enzyme expression patterns in the two media were similar and a considerable number of the identified proteins on two-dimensional gel electrophoresis (2-DE) gels were those involved in biomass degradation. The most abundant cellulolytic enzymes identified in both media were cellobiohydrolases (Cel7A/Cel6A) and endoglucanases (Cel7A/Cel5A) and were found to be more abundant in CMM. We also found that both media can serve as an inducer of xylanolytic enzymes. The main xylanases (XYNI/XYNIV) and xyloglucanase (Cel74A) were found at higher concentrations in the CMM than LCM. Conclusions: We analyzed the prevalent proteins secreted by T. reesei in the CMM and LCM. Here, we show that hydrolytic enzymes are cost-effective and can be produced on cane molasses as a carbon source which can be used to digest lignocellulolytic biomass. © 2014He et al.; licensee BioMed Central Ltd.