lowers the overall yield of H 2 . In such cases, the H 2 yield can be improved by
inoculum pretreatment methods (enrichment of H 2 -producing microorganisms) as
well as by maintaining the proper operating conditions (Ghimire et al. 2015).
2.2.2 Suitability of Microalgal Biomass as a Substrate
Second-generation biofuels produced from the lignocellulosic biomass (agricultural
residues and energy crops cultivated on non-arable lands) have no doubt provided
the solution of the raised criticism regarding the sustainability of first-generation
biofuels (biofuels produced from agricultural substrates). Nevertheless, the native
recalcitrant structure of lignocellulosic biomass limits their hydrolysis by the fermentative bacteria. Indeed, to disrupt the rigid structure and to decrease the crystallinity of lignocellulosic biomass, required pretreatment methods are difficult and
energy intensive. In this respect, third-generation biofuel production utilizing
microalgal biomass as substrate has gained tremendous attention in recent years
(Kumar et al. 2013; Nayak et al. 2014; Roy et al. 2014; Ortigueira et al. 2015; Khan
et al. 2017).
Microalgal biomass offers several potential advantages to be used as an alternative to lignocellulosic feedstock for biofuel (biohydrogen) production, such as:
Fig. 3 Biohydrogen production via dark fermentation using algal biomass as substrate
212
H. Singh and D. Das
inoculum pretreatment methods (enrichment of H 2 -producing microorganisms) as
well as by maintaining the proper operating conditions (Ghimire et al. 2015).
2.2.2 Suitability of Microalgal Biomass as a Substrate
Second-generation biofuels produced from the lignocellulosic biomass (agricultural
residues and energy crops cultivated on non-arable lands) have no doubt provided
the solution of the raised criticism regarding the sustainability of first-generation
biofuels (biofuels produced from agricultural substrates). Nevertheless, the native
recalcitrant structure of lignocellulosic biomass limits their hydrolysis by the fermentative bacteria. Indeed, to disrupt the rigid structure and to decrease the crystallinity of lignocellulosic biomass, required pretreatment methods are difficult and
energy intensive. In this respect, third-generation biofuel production utilizing
microalgal biomass as substrate has gained tremendous attention in recent years
(Kumar et al. 2013; Nayak et al. 2014; Roy et al. 2014; Ortigueira et al. 2015; Khan
et al. 2017).
Microalgal biomass offers several potential advantages to be used as an alternative to lignocellulosic feedstock for biofuel (biohydrogen) production, such as:
Fig. 3 Biohydrogen production via dark fermentation using algal biomass as substrate
212
H. Singh and D. Das