ABSTRACT
Biorefinery process innovations are gaining momentum globally. This chapter emphasizes the urgent need for alternate/waste lignocellulosic substrates by presenting a schematic of the enormous competition between conventional lignocellulosic biomass’s applications for fuel/enzymes and fodder. Brief data on the generation of alternate lignocelluloses, such as municipal wastes of domestic, industrial, hospital, and agricultural origin, are presented. The biochemistry of biomass pretreatment techniques and current advances to counteract the subsequent bioprocess-hampering inhibitors are sketched out. A relationship between transcriptional regulatory mechanisms in significant cellulolytic microbes (predominantly fungi) and the resultant bioprocess modifications for improved cellulase expression from these microbes, which in turn impact the bioreactor operational kinetics (nutrient and oxygen maintenance coefficients; oxygen uptake/transfer rates; limitations to mass transfer; broth rheology; and substrate feeding strategies) are elaborated. The biochemical mechanisms of enzymatic saccharification, its bottlenecks, and contemporary advances relating to integrated, economical bioprocesses have also been elucidated.
