ABSTRACT
Lignocellulose Degradation Intermediates ................................ 160 6.4 Decomposition of Lignocellulose Ingredients ....................................... 160
6.4.1 Cellulose Biodegradation .............................................................. 160 6.4.2 Hemicellulose Biodegradation ..................................................... 162 6.4.3 Lignin Biodegradation .................................................................. 164
6.5 Enzymatic Processes for Lignin and Hemicelluloses Degradation ... 167 6.5.1 Xylanase........................................................................................... 167 6.5.2 Lignin Peroxidase (LiP) ................................................................. 168 6.5.3 Manganese Peroxidase (MnP)...................................................... 168 6.5.4 Laccase (Lac) ................................................................................... 169
6.6 Molecular Aspects ..................................................................................... 171 6.7 Biotechnological Application of Lignocellulose and Its
Biodegradation ........................................................................................... 173 6.7.1 Lignocellulose-Based Technologies Using Unsterile
Substrates ........................................................................................ 174 6.7.2 Bio-Pulping ..................................................................................... 174 6.7.3 Animal Feed ................................................................................... 174 6.7.4 Potential of Lignocellulose in Space Exploration ...................... 175 6.7.5 Organic Acids ................................................................................. 175 6.7.6 Single Cell Protein ......................................................................... 175 6.7.7 Bioactive Compounds ................................................................... 176
6.8 Conclusions ................................................................................................. 176 References ............................................................................................................. 176
Lignocellulosic biomass, composed of forestry, agricultural and agro-industrial wastes, are abundant, renewable and inexpensive energy sources. Such wastes include a variety of materials: sawdust; poplar trees; sugarcane bagasse; waste paper; brewer’s spent grains; switch grass; and straws, stems, stalks, leaves, husks, shells and peels from cereals, such as rice, wheat, corn, sorghum and barley. Lignocellulose wastes are accumulated every year in large quantities, causing environmental problems. However, due to their chemical composition based on sugars and other compounds of interest, they could be utilised for the production of a number of value-added products, such as ethanol, food additives, organic acids, enzymes and others. Therefore, besides the environmental problems caused by their accumulation in nature, the nonuse of these materials results in a loss of potentially valuable sources (Mishra and Thakur 2011).
