Solid state fermentation and crude cellulase based bioconversion of potential bamboo biomass to reducing sugar for bioenergy production.

BACKGROUND: Lignocellulosic biomass from bamboo is an attractive feedstock for the bioethanol industry owing to its high cellulosic content and fast growth rate. In this study, powdery biomass was first enzymatically delignified and then saccharified using crude enzymes.

RESULTS: The biological pretreatment decreased the lignin content of the biomass from an initial value of 295 to 137.7 g kg-1 , with a simultaneous increase in exposed cellulose content from 379.3 to 615.9 g kg-1 . For optimization of the saccharification, response surface methodology was adopted using a three-factor/three-level Box-Behnken design with crude fungal cellulase loading (FPU g-1 substrate), substrate concentration (% w/v) and saccharification temperature (°C) as the main process parameters. A maximum saccharification yield of 47.19% was achieved under the optimized conditions (cellulase enzyme 18.4 FPU g-1 substrate, substrate concentration 1.0% w/v, temperature 39.49 °C). Biological delignification and saccharification of the biomass were further confirmed through scanning electron microscopy analysis.

CONCLUSION: It is evident from the study that bamboo, as a renewable energy bioresource, can be hydrolysed to reducing sugars by using crude laccase/cellulase enzymes of fungal origin with good saccharification yield. Thus crude enzyme preparations could be utilized efficiently for eco-friendly and cost-effective bioethanol production. © 2018 Society of Chemical Industry.