title: Capillary Electrophoresis as Tool for Diastereomeric Separation in a Trichilia catigua Fraction.
abstract: BACKGROUND
  The tree Trichilia catigua, popularly known as "catuaba", shows several biological activities and has emerged as a potential source of new drugs. Considering that more than 10 species are known under the same popular name, regulatory agencies require more rigorous quality control of this medicinal plant.
  
  
  OBJECTIVE
  To develop and validate a methodology using capillary electrophoresis (CE) with ultraviolet (UV) detection for analysing polyphenols in the ethyl-acetate fraction (EAF) of Trichilia catigua.
  
  
  METHODS
  Different electrophoretic conditions (such as wavelength of UV detection, voltage, buffer concentration and pH, cyclodextrin type and concentration) were investigated. After optimisation, borate buffer 80 mmol/L at pH 8.80 with 2-hydroxypropyl-β-cyclodextrin 10 mmol/L was selected as background electrolyte. A voltage reduction was used to improve the separation of a diastereomeric pair of cinchonains.
  
  
  RESULTS
  The method proved to be simple, sensitive, accurate, linear, precise and reproducible. For the first time in natural products analysis, a voltage reduction and hydroxypropyl-β-cyclodextrin were used to improve the separation of diastereomeric pairs. Until now, this is the only described methodology able to separate catechin, epicatechin, cinchonains Ia, Ib, IIa, and IIb from Trichilia catigua samples on the same run in less than 12 min. When compared to the high performance liquid chromatography with photo-diode array detection (HPLC-PDA) method previously developed by our research group, the CE method was more efficient, faster, less expensive and less polluting.
  
  
  CONCLUSIONS
  Our results demonstrate that this method could be employed in a quality-control laboratory for the quantification of polyphenols in EAF of Trichilia catigua. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Programa de Pós-Graduação em Ciências Farmacêuticas, Department of Pharmacy, Universidade Estadual de Maringá, Maringá, PR. Avenida Colombo, 5790, BR-87020-900, Maringá, PR, Brazil.
authors.forename: Ana Luiza
authors.initials: AL
authors.lastname: Sereia
authors.affiliation: Programa de Pós-Graduação em Ciências Farmacêuticas, Department of Pharmacy, Universidade Estadual de Maringá, Maringá, PR. Avenida Colombo, 5790, BR-87020-900, Maringá, PR, Brazil.
authors.forename: Renata
authors.initials: R
authors.lastname: Longhini
authors.affiliation: Programa de Pós-Graduação em Ciências Farmacêuticas, Department of Pharmacy, Universidade Estadual de Maringá, Maringá, PR. Avenida Colombo, 5790, BR-87020-900, Maringá, PR, Brazil.
authors.forename: Gisely Cristiny
authors.initials: GC
authors.lastname: Lopes
authors.affiliation: Programa de Pós-Graduação em Ciências Farmacêuticas, Department of Pharmacy, Universidade Estadual de Maringá, Maringá, PR. Avenida Colombo, 5790, BR-87020-900, Maringá, PR, Brazil.
authors.forename: João Carlos Palazzo
authors.identifier: http://orcid.org/0000-0002-7532-3395
authors.initials: JCP
authors.lastname: de Mello
mesh_terms: D000085:Acetates / Q000737:chemistry; D044946:Biflavonoids / Q000032:analysis / Q000737:chemistry; D002392:Catechin / Q000032:analysis / Q000737:chemistry; D002396:Catechols / Q000032:analysis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003505:Cyclodextrins / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D057230:Limit of Detection; D029582:Meliaceae / Q000737:chemistry*; D059808:Polyphenols / Q000032:analysis; D044945:Proanthocyanidins / Q000032:analysis / Q000737:chemistry; D011753:Pyrones / Q000032:analysis / Q000737:chemistry; D015203:Reproducibility of Results; D013237:Stereoisomerism; D014466:Ultraviolet Rays
chemical_list: D000085:Acetates; D044946:Biflavonoids; D002396:Catechols; D003505:Cyclodextrins; D059808:Polyphenols; D044945:Proanthocyanidins; D011753:Pyrones; C513224:cinchonain Ib; C479580:procyanidin B2; C007650:ethyl acetate; D002392:Catechin
keywords: Trichilia catigua; capillary electrophoresis; chiral separation; cinchonains; cyclodextrins; voltage reduction