| Summary: | Production of high value-added products from lignocelluloses is an economically sustainable alternative to decreasing dependence on fossil fuels and making the chemical processes environmentally friendly. In this study, different methodologies of alkaline (Ca(OH)<sub>2</sub> and NaOH), dilute acid (10%w/w H<sub>2</sub>SO<sub>4</sub>), hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), alkaline peroxide oxidation (H<sub>2</sub>O<sub>2</sub>/Ca(OH)<sub>2</sub> and H<sub>2</sub>O<sub>2</sub>/NaOH), and molten hydrated salt (MHS) mediated (ZnCl<sub>2</sub>.4H<sub>2</sub>O) pretreatments were employed in the hydrolysis of corncob amenable to enzymatic hydrolysis. Optimal enzyme hydrolysis temperature (considering 45 and 50 ℃) and time (2, 24, 72, and 96 h) were investigated for each pretreatment procedure to ascertain the concentrations of glucose, xylose, and total sugar present in the corncob. At 45 ℃ and 96 h, NaOH alkaline pretreatment achieved the best optimum total sugar production of 75.54 mg/mL (about 54% and 88% increments compared to dilute acid pretreatment (35.06 mg/mL total sugars) and MHS (9.32 mg/mL total sugar) pretreatment respectively). In this study, total sugars production increased appreciably at 45 ℃ and longer hydrolysis period (96 h) compared to hydrolysis at 50 ℃ (with maximum total sugars production of 18.00 mg/mL at 96 h). Scanning electron microscopic imaging of the untreated and treated samples displayed cell wall distortion and surface disruptions.
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