Allomorphic Transformation of Cellulose for Enhancing Enzymatic Accessibility

Abstract

In recent decades, lignocellulosic biomass has attracted increasing attention as a sustainable alternative to fossil-fuel-based resources. However, the compact and highly crystalline structure of cellulose remains a major limitation to its effective utilization. In this study, the allomorphic transformation of cellulose was induced through chemical treatments using sodium hydroxide (NaOH) and ethylenediamine (EDA), enabling the conversion of native cellulose I into cellulose II and cellulose III, respectively. The resulting changes in the crystalline structure were systematically investigated using X-ray diffraction and Raman spectroscopy. Both NaOH- and EDA-treated celluloses exhibited enhanced enzymatic digestibility compared to untreated cellulose, consistent with the observed modifications in the crystal structure. Nevertheless, some results indicate that crystalline structure is not an absolute determining factor, but rather one of several parameters, including specific surface area, particle size, and degree of polymerization.