title: Interval multivariate curve resolution in the dereplication of HPLC-DAD data from Jatropha gossypifolia.
abstract: BACKGROUND
  Jatropha gossypifolia has been used quite extensively by traditional medicine for the treatment of several diseases in South America and Africa. This medicinal plant has therapeutic potential as a phytomedicine and therefore the establishment of innovative analytical methods to characterise their active components is crucial to the future development of a quality product.
  
  
  OBJECTIVE
  To enhance the chromatographic resolution of HPLC-UV-diode-array detector (DAD) experiments applying chemometric tools.
  
  
  METHODS
  Crude leave extracts from J. gossypifolia were analysed by HPLC-DAD. A chromatographic band deconvolution method was designed and applied using interval multivariate curve resolution by alternating least squares (MCR-ALS).
  
  
  RESULTS
  The MCR-ALS method allowed the deconvolution from up to 117% more bands, compared with the original HPLC-DAD experiments, even in regions where the UV spectra showed high similarity. The method assisted in the dereplication of three C-glycosylflavones isomers: vitexin/isovitexin, orientin/homorientin and schaftoside/isoschaftoside.
  
  
  CONCLUSIONS
  The MCR-ALS method is shown to be a powerful tool to solve problems of chromatographic band overlapping from complex mixtures such as natural crude samples.
authors.affiliation: Nucleus of Bioassays, Biosynthesis and Ecophysiology of Natural Products, São Paulo State University Chemistry Institute, Department of Organic Chemistry, Rua Prof. Francisco Degni no 55 - CP355, 14800-900, Araraquara, São Paulo, Brazil.
authors.forename: Alan Cesar
authors.initials: AC
authors.lastname: Pilon
authors.forename: R L
authors.initials: RL
authors.lastname: Carneiro
authors.forename: F
authors.initials: F
authors.lastname: Carnevale Neto
authors.forename: Vanderlan
authors.initials: V
authors.lastname: da S Bolzani
authors.forename: I
authors.initials: I
authors.lastname: Castro-Gamboa
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D005419:Flavonoids / Q000032:analysis / Q000737:chemistry; D005960:Glucosides / Q000032:analysis / Q000737:chemistry; D006027:Glycosides / Q000032:analysis / Q000737:chemistry; D031286:Jatropha / Q000737:chemistry*; D016018:Least-Squares Analysis; D015999:Multivariate Analysis; D010936:Plant Extracts / Q000032:analysis / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D014466:Ultraviolet Rays
chemical_list: D005419:Flavonoids; D005960:Glucosides; D006027:Glycosides; D010936:Plant Extracts; C515112:schaftoside; C515113:isoschaftoside; C065886:orientin