Optimal Method for Production of Amorphous Cellulose with Increased Enzymatic Digestibility

In this paper, a simple and cheap method for producing of amorphous cellulose was studied by treating the initial cellulosic material (MCC and waste paper) with a cold solvent, such as aqueous solution of 7% NaOH/12% Urea, at the various ratios of the solvent to cellulose (v/w) (R). If was found that after treatment of cellulose materials with the solvent at R ≥5, a completely amorphous cellulose (AC) is formed. Due to high digestibility, the AC with concentration of 50 g/L is converted to glucose almost completely for 48 h under the action of cellulolytic enzyme CTec-3 with a dose of 30 mg/g solid sample. Such sample can be used as an amorphous standard in the study of crystallinity degree and enzymatic hydrolysis of various types of cellulose and lignocellulose. It was found that enzymatic saccharification is most advantageous to carry out at elevated concentrations of AC, 150 g /L. Due to high cost of MCC, it is preferable to use a cheap cellulose raw material, such as mixed waste paper (MWP), for the commercial production of AC and glucose. The resulting glucose can find application in biotechnology as a promising nutrient for various microorganisms.