"Functionalized waste cellulose with antimicrobical activity"

Soybean hulls are one of the main by-products of soybean crushing and they are usually destinedto become a putrescible waste. In a previous study, exhausted soybean hulls after the extractionof soybean peroxidase (an enzyme used for different applications) were employed as adsorbentsof aqueous metal contaminants for water remediation [1]. In this work, such waste of soybeanhulls were subjected to an acid-base treatment to isolate cellulose. The obtained material wasfunctionalized with amino propyl groups [2] for the achievement of new sustainable materialswith antimicrobial properties. For comparison purpose, analogous materials were synthesizedstarting from commercial cellulose. The amino-functionalization process resulted effective,since the antimicrobial activity of all the modified celluloses -tested by preliminary trialsfollowing the ASTM E 2149-2013 procedure- was outstanding against both Gram positive andGram-negative bacteria. Particular attention was paid to the efficiency and sustainability of allthe chemical processes with the use of waste materials, green solvents and sustainableprocedures. The physical-chemical features of the samples were analyzed by several techniquessuch as electron scanning microscopy, infrared spectroscopy, thermogravimetry, differentialscanning calorimetry. Preliminary results showed as the different synthetic procedures and thedifferent starting cellulose samples influenced both the thermal stability and the microstructuralorder.