Cellulose Nanofibers and Reducing Sugars from Soybean Straw: An Investigation of the Enzymatic Activity and the Biomass Concentration Effect by Response Surface Methodology

摘要: This study investigated the effect of different conditions of enzymatic hydrolysis on the production of nanofibers and reducing sugars from soybean straw. The milled and sieved lignocellulosic biomass underwent two an alkaline pretreatment using NaOH 5%(PT1) or 17.5%(PT2), bleaching (H 2 O 2 4%) and enzymatic (Optimash VR™; Dupont, USA) treatments. The effects of the enzymatic activity and the pretreated soybean straw concentration were evaluated using a Rotational Compound Central Design (DCCR) 2 2. An increase in the enzymatic activity and a decrease in the concentration of soybean in the suspension enhanced the production of sugars. This effect was due to the higher ratio of enzymatic activity/soybean straw pretreated concentration. Enzymatic activity disfavoured the nanofiber production for PT1, but favoured for PT2, probably due to the higher defibrillation when higher alkaline concentration is used. For both materials (PT1 and PT2), the lower soybean straw concentration furnished more stable suspensions. The optimal condition for the simultaneous production of reducing sugars and nanofibers was 4.0 g of biomass and enzymatic activity of 600 CMCU. This study shows that soybean straw has great potential for the industrial production of cellulose nanofibers and reducing sugars due to processing efficiency and low raw material cost.