Enzymatic hydrolysis of poppy straw to sugars and analysis of its kinetics

At this study response surface methodology (RSM) was employed to optimize dilute alkaline pretreatment condition for maximum glucose yield of poppy stalk with respect to NaOH concentration (1.0–3.0%, w/v), pretreatment temperature (60−90°C) and pretreatment time (30−90 min). Recovery of cellulose ranged from 61.02% to 99.14% based on the initial cellulose content in the raw material. The highest lignin removal (43.43 %) was obtained at the pretreatment conditions of 90 °C, 3.50% NaOH for 90 min. The optimum pretreatment conditions for maximum glucose yield after enzymatic hydrolysis were found as 2.40% w/v NaOH, 70 min, and 80 °C. At this condition, experimental glucose and xylose yields were found as 499.35 mg/g glucan, and 498.66 mg xylose/ g xylan, respectively. Enzymatic hydrolysis kinetics of pretreated poppy stalks was also modelled based on the Michaelis-Menten and diffusion limited kinetic models.