COMBINATION OF ALKALINE AND ENZYMATIC PRE-TREATMENT TO INCREASE BIO-METHANE PRODUCTION POTENTIAL OF SORGHUM AND WHEAT STRAW

摘要

the purpose of this study was to increase methane production by enzymatic and combined alkalineenzymaticpre-treatments on ensiled sorghum forage and wheat straw. Sodium hydroxide pre-treatment wasconducted by soaking samples in a NaOH solution. Enzymatic pre-treatment was comparatively performedemploying four commercial preparations. Enzyme preparations were first characterized for their protein, CMCase(endoglucanase), xylanase and avicelase activities, and then added to untreated or alkaline pre-treated substrates. Toassess the effect of the applied pre-treatment on the methane production, Biochemical Methane Potential (BMP) tests,before and after the enzymatic and the combined alkaline-enzymatic pre-treatment, were performed. Glucose was theprevailing monosaccharide released by enzymatic treatments, but xylose, mannose and galactose, as well as arabinoseand glucuronic acid were also found. Combined alkaline-enzymatic pre-treatment resulted in the highest methaneyield increase (+32% and +76% for ensiled sorghum and wheat straw respectively).