Acidification treatment of lignin from sugarcane bagasse results in fractions of reduced polydispersity and high free-radical scavenging capacity

Author(s)

Brenelli, Livia Beatriz ^{[1, 2]} ; Mandelli, Fernanda ^{[2, 3]} ; Mercadante, Adriana Zerlotti ^[3] ; de Moraes Rocha, George Jackson ^[2] ; Rocco, Silvana Aparecida ^[4] ; Craievich, Aldo Felix ^[5] ; Goncalves, Adilson Roberto ^[2] ; Centeno, Danilo da Cruz ^[6] ; de Oliveira Neto, Mario ^[7] ; Squina, Fabio Marcio ^[2]

Affiliation

^[1] Univ Campinas UNICAMP, Inst Biol, BR-13083862 Campinas, SP - Brazil

^[2] CNPEM, Lab Nacl Ciencia & Tecnol Bioetanol CTBE, Caixa Postal 6192, BR-13083970 Campinas, SP - Brazil

^[3] Univ Campinas UNICAMP, Fac Engn Alimentos, Dept Ciencias Alimentos, BR-13083862 Campinas, SP - Brazil

^[4] CNPEM, Lab Nacl Biociencias LNBIO, Caixa Postal 6192, BR-13083970 Campinas, SP - Brazil

^[5] Univ Sao Paulo, Inst Fis, BR-05508900 Sao Paulo - Brazil

^[6] Univ Fed ABC, CCNH, BR-09606070 Sao Bernardo Do Campo, SP - Brazil

^[7] Univ Estadual Paulista Julio Mesquite Filho UNESP, Inst Biociencias, Dept Fis & Biofis, BR-18618970 Botucatu, SP - Brazil

• Document type: Journal article
• Source: INDUSTRIAL CROPS AND PRODUCTS; v. 83, p. 94-103, MAY 2016.
• Web of Science Citations: 10

Abstract

Lignin constitutes up to one-third of the material found in plant cell walls and is considered the second most abundant natural polymer in the world. Despite unique characteristics of lignin, it is mostly used for low-value commercial applications. In this study, lignin obtained after alkaline treatment of steam exploded sugarcane bagasse was submitted to an acidification process. The soluble fractions produced at different pH values were comprehensively characterized and in vitro antioxidant capacity against reactive oxygen (ROO center dot and H2O2) and nitrogen (ONOO-) species was evaluated. The soluble fraction obtained at pH 2 exhibited the highest scavenging capacities against all species tested (10.2 +/- 0.7 mmol Trolox equivalent g(-1) for ROO center dot, IC30= 14.9 mu g mL(-1) for H2O2 and IC50-2.3 mu g mL(-1) for ONOO-) and the lowest polydispersity value (1.2) compared to others fractions. According to the SAXS data, the soluble fractions obtained at pH 4 and pH 2 consisted of small nanometer-sized discs and low molecular weight polyphenolic clusters, while soluble fractions obtained at high pH predominated wide lignin nanoparticles and larger aggregates. Mass spectroscopy analysis revealed the presence of phenolic and non-phenolic compounds, well-known as efficient antioxidants, which were identified in all soluble fractions. Collectively, our results provided further demonstration that acidification treatment is a promising strategy to upgrade heterogeneous lignin-enriched stream from sugarcane bagasse, such as preparations with homogeneous compositions and high antioxidant activity. (c) 2015 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 14/50371-8 - Integrated enzyme discovery and pathway optimization for bagase valorization
• Grantee: Fábio Márcio Squina
• Support type: Program for Research on Bioenergy (BIOEN) - Regular Program Grants
• FAPESP's process: 13/03061-0 - Characterization and antioxidant capacity of fractions of lignin extracted from sugarcane bagasse
• Grantee: Lívia Beatriz Brenelli de Paiva
• Support type: Scholarships in Brazil - Doctorate