Saccharification of different sugarcane bagasse varieties by enzymatic cocktails produced by Mycothermus thermophilus and Trichoderma reesei RP698 cultures in agro-industrial residues

Lignocellulosic biomasses are promising sources for the obtaining of clean energy through their bioconversion into ethanol. Their sacchariflcation involves a multi-enzymatic system. Here, we evaluated the hydrolysis of a mixture of sugarcane bagasse varieties (SCB), Energy cane fiber (EC), and sugarcane bagasse from the SP80-3280 variety, all in natura, using fungal enzymatic extracts obtained from Mycothermus thermophilus and Trichoderma reesei RP698 cultures supplemented with various agroindustrial residues. The enzymatic extracts from both fungi, when grown in a corn cob and corn straw, led to the highest sugarcane hydrolysis. For M. thermophilus, the reducing sugars released (mg/mL) were 1.21 +/- 0.12, 1.25 +/- 0.14, and 0.98 +/- 0.05 for SCB, EC and SP80-3280, respectively; for T. reesei, the reducing sugars were 0.84 +/- 0.08, 0.89 +/- 0.06 and 0.68 +/- 0.03 for SCB, SP80-3280, and EC, respectively. The cocktail obtained from the co-cultivation of these fungi in corn straw at 35 degrees C showed the best hydrolysis results, the release of sugars (mg/mL) was 1.31 +/- 0.06 (SCB), 2.18 +/- 0.08 (EC) and 1.67 +/- 0.09 (SP80-3280). Scanning electron microscopy and thermogravimetric analysis confirmed changes in the fiber structures after enzymatic hydrolysis. Thus, these fungi were shown to be promising for an enzymatic cocktail design and sugarcane biomass sacchariflcation. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study evaluated the hydrolysis of different sugarcane bagasse varieties using fungal enzymatic extracts, showing that M. thermophilus and T. reesei had the best hydrolysis efficiency when grown in corn straw. The co-cultivation of these fungi in corn straw at 35 degrees C resulted in the highest release of sugars from mixed sugarcane bagasse, indicating their promising potential for enzymatic cocktail design and sacchariflcation of sugarcane biomass.