Chaetomium globosporum: A novel laccase producing fungus for improving the hydrolyzability of lignocellulosic biomass

Rapid economic growth and urbanization is imposing an unseen pressure on energy sector to fulfill the increasing energy demand. Non edible horticultural residues viz. wheat and pearl millet straw have the potential to become an economical resource for waste to energy conversion. However, maximum hydrolyzability of the crop residues is a prerequisite for efficient conversion of complex organic materials into biofuels. In the present study, mycological treatment of wheat and pearl millet straw was accomplished by employing Chaetomium globosporum. The straw samples were exposed to mycological treatment for 14, 28 and 42 days. The improvement in hydrolyzability of straw was assessed by estimating the increase in reducing sugar release. The competence of Chaetomium globosporum for treating the straw samples was evaluated by measuring the % lignin removal after treatment. Furthermore, the structural and morphological changes in the straw samples after mycological treatment were examined by using scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction analysis. The results revealed 124 and 91% increase in reducing sugar release along with 43 and 41% removal of lignin for wheat and pearl millet straw respectively. Significant differences were also observed in in the structure, crystallanity and surface morphology.