Using Commercial Enzymes to Produce Cellulose Nanofibers from Soybean Straw

Author(s)

Martelli-Tosi, Milena ; Torricillas, Marcela da Silva ; Martins, Maria Alice ; Garrido de Assis, Odilio Benedito ; Tapia-Blacido, Delia Rita

• Document type: Journal article
• Source: Journal of Nanomaterials; v. 2016, p. 10-pg., 2016-01-01.

Abstract

This study used commercial enzymes to isolate cellulose nanofibrils (CN) and produce sugars from chemically pretreated soybean straw (SS) (stem, leaves, and pods) by alkali (NaOH 5 or 17.5% v/v at 90 degrees C for 1 h or at 30 degrees C for 15 h) and bleaching (NaClO2 3.3% or H2O2 4%) pretreatments. Depending on the pretreatment applied to the soybean straw, the yield of CN varied from 6.3 to 7.5 g of CN/100 g of SS regardless of the concentration of the alkaline solution (5 or 17.5%). The CN had diameter of 15 nm, measured over 300 nm in length, and had high electrical stability (zeta potentials ranged from -20.8 to -24.5). Given the XRD patterns, the crystallinity index (CrI) of CN ranged from 45 to 68%, depending on the chemical pretreatment the startingmaterial was submitted to. CN obtained from SS treated with NaOH 17.5% and H2O2 (CrI = 45%) displayed better thermal stability probably because a lignin-cellulose complex emerged. The soluble fraction obtained in the first step of CN production contained a large amount of reducing sugars (11.2 to 30.4 g/100 g of SS). SS seems to be a new promising industrial source to produce CN via enzymatic-mechanical treatment, leading to large amounts of reducing sugars for use in bioenergy production. (AU)

• FAPESP's process: 16/16222-0 - Using commercial enzymes to produce cellulose nanofibers from soybean straw
• Grantee: Milena Martelli Tosi
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• FAPESP's process: 12/22154-7 - Isolation of cellulose nanofibers from soybean by-products and their applicability as reinforcement material in biodegradable films
• Grantee: Milena Martelli Tosi
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 14/02432-8 - Isolation of cellulose nanofibers from soybean by-products using chemical, enzymatic and physical treatments
• Grantee: Marcela da Silva Torricillas
• Support Opportunities: Scholarships in Brazil - Scientific Initiation