title: Determination of disease biomarkers in Eucalyptus by comprehensive two-dimensional gas chromatography and multivariate data analysis.
abstract: In this paper is reported the use of the chromatographic profiles of volatiles to determine disease markers in plants - in this case, leaves of Eucalyptus globulus contaminated by the necrotroph fungus Teratosphaeria nubilosa. The volatile fraction was isolated by headspace solid phase microextraction (HS-SPME) and analyzed by comprehensive two-dimensional gas chromatography-fast quadrupole mass spectrometry (GC×GC-qMS). For the correlation between the metabolic profile described by the chromatograms and the presence of the infection, unfolded-partial least squares discriminant analysis (U-PLS-DA) with orthogonal signal correction (OSC) were employed. The proposed method was checked to be independent of factors such as the age of the harvested plants. The manipulation of the mathematical model obtained also resulted in graphic representations similar to real chromatograms, which allowed the tentative identification of more than 40 compounds potentially useful as disease biomarkers for this plant/pathogen pair. The proposed methodology can be considered as highly reliable, since the diagnosis is based on the whole chromatographic profile rather than in the detection of a single analyte.
authors: Institute of Chemistry - University of Campinas (Unicamp), CP 6154, 13084-970 Campinas, São Paulo, Brazil.
authors: Leandro Wang
authors: LW
authors: Hantao
authors: Helga Gabriela
authors: HG
authors: Aleme
authors: Martha Maria
authors: MM
authors: Passador
authors: Edson Luiz
authors: EL
authors: Furtado
authors: Fabiana Alves de Lima
authors: FA
authors: Ribeiro
authors: Ronei Jesus
authors: RJ
authors: Poppi
authors: Fabio
authors: F
authors: Augusto
mesh_terms: D001203:Ascomycota / Q000502:physiology; D015415:Biomarkers / Q000032:analysis* / Q000378:metabolism; D002849:Chromatography, Gas / Q000295:instrumentation / Q000379:methods*; D005052:Eucalyptus / Q000737:chemistry* / Q000378:metabolism / Q000382:microbiology; D015999:Multivariate Analysis; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology; D055549:Volatile Organic Compounds / Q000032:analysis* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D055549:Volatile Organic Compounds