Enzymatic Deconstruction of Sugarcane Bagasse and Straw to Obtain Cellulose Nanomaterials

The application of green process engineering strategies to obtain high-value, eco-friendly, and biodegradable materials from residual lignocellulosic biomass can contribute to the sustainability of future biorefineries. Here, we investigated the potential of sugarcane bagasse and straw as lignocellulosic biomass feedstocks to obtain nanocellulose, using the enzymatic hydrolysis route as a platform. The fibers were submitted to a purification process followed by enzymatic hydrolysis with a commercial enzyme cocktail. The cellulose nanomaterials obtained from both fibers (sugarcane bagasse and straw) presented a high crystallinity index (∼70%) and thermal stability (degradation onset temperatures higher than 300 °C). After the enzymatic hydrolysis, a centrifugation step was used to separate the cellulose nanocrystals (CNC) present in the nanocellulose samples. The increase of the duration of enzymatic hydrolysis resulted in an increase of the CNC content and decreases in the diameter and length of the CNC. These findings indicated the potential of using the enzymatic route as a platform to obtain nanocellulose as a value-added bioproduct from both sugarcane bagasse and straw. In addition to being eco-friendly, this process also releases a stream rich in soluble sugars that can be used to produce ethanol or other biobased products, within the biorefinery concept.