Sugarcane tops pretreated with different methods such as dilute acid, surfactantassisted acid, and surfactant-assisted ultrasound were subjected to enzymatic hydrolysis, and the optimum conditions of 11.25% (w/w) biomass concentration, 50 FPU
enzyme concentration, 0.2% of surfactant concentration, and 60 h incubation time
yielded the maximum reducing sugars such as 0.665 g/g [8], 0.711 g/g [6], and
0.649 g/g [14], respectively. Alkaline-pretreated sugarcane tops were subjected to
enzymatic hydrolysis with optimum conditions of 11.25% (w/w) biomass concentration, enzyme concentration of 50 FPU, 0.2% of surfactant concentration, and
incubation time of 42 h; the yield of fermentable sugars was about 0.779 g/g
[11]. Enzymatic hydrolysis of microwave-pretreated SCT with optimum conditions
such as biomass concentration of 10% (w/w), cellulase loading of 100 FPU/g,
surfactant concentration of 0.04% (w/w), and incubation time of 72 h yielded
0.376 g/g glucose [15].
Enzymatic-pretreated SCT was hydrolyzed with 15% w/v substrate loading;
50 FPU/g enzyme loading maintained at pH 5 for 48 h yielded 117.16 g/L of
reducing sugar [1]. Enzymatic hydrolysis on the sequential pretreated SCT showed
a maximum reducing sugar yield of 0.796 g/g with 5% (w/w) biomass loading,
80 FPU cellulase loading, 0.25% (w/w) surfactant concentration, and 48 h incubation time [16]. Enzymatic saccharification of laccase enzyme-pretreated SCT yielded
508 mg/g of reducing sugar with the optimal conditions of 14% (w/v) solid loading,
50
C temperature, 7 h incubation time, and 19.33 IU/ml enzyme titer at pH 5
[3]. Enzymatic (laccase)-pretreated SCT showed 3.3-fold increase in fermentable
sugars after delignification [4].
Fig. 4 Steps involved in enzymatic hydrolysis
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