Bioethanol production by enzymatic saccharification of Salix viminalis var. gigantea biomass

The biomass of Salix viminalis var. gigantea was evaluated for the possibility of using it as a bioenergy resource. The chemical analysis of S. viminalis var. gigantea leaf biomass showed presence of components such as extractives (1.6%), lignin (44.2%), hemicellulose (16.4%), and cellulose (37.8%), whereas its stem was composed of other extractives (0.6%), lignin (19.4%), hemicellulose (35.1%), and cellulose (44.9%). Leaf and stem biomass samples of S. viminalis var. gigantea were hydrolyzed using two commercial enzymes, celluclast and viscozyme. The hydrolysis of S. viminalis var. gigantea biomass was different according to enzyme mixtures and their strengths. The optimal enzyme combination was found to be celluclast (59 FPU g ⁻¹ substrate) and viscozyme (24 FBG g ⁻¹ substrate). Glucose content in leaf and stem biomass was 16.81 g and 27.45 g per 100 g raw material, respectively, after 72 hr of enzyme treatment. The ethanol production from stem and leaf biomass was estimated as 4.45 g and 7.94 g, respectively. The biomass and enzyme hydrolysis biomass served as feedstock for ethanol production by fermentation.