Functionalized cellulose from waste soybean hulls with antimicrobial activity

Soybean hulls are one of the main by-products of soybean crushing, usually destined to become a putrescible waste. Exhausted soybean hulls, after the extraction of soybean peroxidase (a useful enzyme), were subjected to an acid-base treatment to isolate cellulose, which was in turn functionalized with aminopropyl groups for the achievement of new sustainable materials with antimicrobial properties. The amino-functionalization process resulted effective, since the antimicrobial activity was outstanding against both Gram positive and negative bacteria. The physical-chemical features of the samples were analyzed by several techniques, showing that the different functionalization procedures influenced the thermal stability and the microstructural order.