title: The acetyl bromide method is faster, simpler and presents best recovery of lignin in different herbaceous tissues than Klason and thioglycolic acid methods.
abstract: We compared the amount of lignin as determined by the three most traditional methods for lignin measurement in three tissues (sugarcane bagasse, soybean roots and soybean seed coat) contrasting for lignin amount and composition. Although all methods presented high reproducibility, major inconsistencies among them were found. The amount of lignin determined by thioglycolic acid method was severely lower than that provided by the other methods (up to 95%) in all tissues analyzed. Klason method was quite similar to acetyl bromide in tissues containing higher amounts of lignin, but presented lower recovery of lignin in the less lignified tissue. To investigate the causes of the inconsistencies observed, we determined the monomer composition of all plant materials, but found no correlation. We found that the low recovery of lignin presented by the thioglycolic acid method were due losses of lignin in the residues disposed throughout the procedures. The production of furfurals by acetyl bromide method does not explain the differences observed. The acetyl bromide method is the simplest and fastest among the methods evaluated presenting similar or best recovery of lignin in all the tissues assessed.
authors.affiliation: Department of Agronomy, State University of Maringá, Maringá, Paraná, Brazil.
authors.forename: Flavia Carolina
authors.initials: FC
authors.lastname: Moreira-Vilar
authors.affiliation: Department of Biochemistry, State University of Maringá, Maringá, Paraná, Brazil.
authors.forename: Rita de Cássia
authors.initials: Rde C
authors.lastname: Siqueira-Soares
authors.affiliation: Department of Biochemistry, State University of Maringá, Maringá, Paraná, Brazil.
authors.forename: Aline
authors.initials: A
authors.lastname: Finger-Teixeira
authors.affiliation: Department of Biochemistry, State University of Maringá, Maringá, Paraná, Brazil.
authors.forename: Dyoni Matias
authors.initials: DM
authors.lastname: de Oliveira
authors.affiliation: Department of Biochemistry, State University of Maringá, Maringá, Paraná, Brazil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Ferro
authors.affiliation: Brazilian Bioethanol Science and Technology Laboratory, Campinas, São Paulo, Brazil.
authors.forename: George Jackson
authors.initials: GJ
authors.lastname: da Rocha
authors.affiliation: Department of Biochemistry, State University of Maringá, Maringá, Paraná, Brazil.
authors.forename: Maria de Lourdes L
authors.initials: Mde L
authors.lastname: Ferrarese
authors.affiliation: Department of Biochemistry, State University of Maringá, Maringá, Paraná, Brazil.
authors.forename: Wanderley Dantas
authors.initials: WD
authors.lastname: dos Santos
authors.affiliation: Department of Biochemistry, State University of Maringá, Maringá, Paraná, Brazil.
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Ferrarese-Filho
mesh_terms: D000085:Acetates / Q000737:chemistry*; D005591:Chemical Fractionation / Q000379:methods*; D005662:Furaldehyde / Q000031:analogs & derivatives / Q000032:analysis; D008031:Lignin / Q000032:analysis* / Q000302:isolation & purification*; D055595:Mechanical Phenomena; D031786:Saccharum / Q000737:chemistry / Q000166:cytology*; D013025:Glycine max / Q000737:chemistry / Q000166:cytology*; D013864:Thioglycolates / Q000737:chemistry*; D013997:Time Factors
chemical_list: D000085:Acetates; D013864:Thioglycolates; C008046:5-hydroxymethylfurfural; C017487:2-mercaptoacetate; D008031:Lignin; D005662:Furaldehyde; C412887:acetyl bromide