Greater Importance of Structural Changes Over Lignin Removal in Impacting the Enzymatic Hydrolysis of Crop Straws

[Image: see text] The importance of structural changes and lignin removal in influencing the enzymatic hydrolysis of crop straws was investigated. Alkaline pretreatment of corn stover (CS) and rice straw (RS) was conducted to remove lignin. It was found that alkaline pretreatment caused more lignin removal from CS than RS under the same condition, and CS and RS treated at 40 °C (CS40 and RS40) attained less lignin removal than those treated at 80 °C (CS80 and RS80). However, CS40 achieved glucan conversion efficiency of 70.77% which was 11.85% less than that of RS40, and similar glucan conversion efficiencies were obtained for RS 40 and RS80. Structural observation showed that the connection among single fiber bundle of CS40 was tighter than that of RS40, while those of RS40 and RS80 were loose. It meant that structural changes might be more important than lignin removal to influence enzymatic hydrolysis of crop straws.