title: Chiral cyclodextrin-modified micellar electrokinetic chromatography and chemometric techniques for green tea samples origin discrimination.
abstract: Catechins and methylxanthines were determined in 92 green tea (GT) samples originating from Japan and China by using micellar electrokinetic chromatography with the addition of (2-hydroxypropyl)-β-cyclodextrin. GT samples showed high concentrations of (-)-epigallocatechin gallate and caffeine, with (-)-epigallocatechin, (-)-epicatechin gallate and (-)-epicatechin in relevant content and (+)-catechin, (-)-catechin and theobromine in much lower amounts. The amount of all the considered compounds was higher for Chinese GTs, with the exception of (-)-epicatechin gallate. Pattern recognition methods were applied to discriminate GTs according to geographical origin, which is an important factor to determine quality and reputation of a commercial tea product. Data analysis was performed by principal component analysis and hierarchical cluster analysis as exploratory techniques. Linear discriminant analysis and quadratic discriminant analysis were utilized as discrimination techniques, obtaining a very good rate of correct classification and prediction.
authors.affiliation: Department of Chemistry "U. Schiff", University of Florence, Via U. Schiff 6, 50019 Sesto Fiorentino, Florence, Italy. Electronic address: benedetta.pasquini@unifi.it.
authors.forename: Benedetta
authors.initials: B
authors.lastname: Pasquini
authors.affiliation: Department of Chemistry "U. Schiff", University of Florence, Via U. Schiff 6, 50019 Sesto Fiorentino, Florence, Italy. Electronic address: serena.orlandini@unifi.it.
authors.forename: Serena
authors.initials: S
authors.lastname: Orlandini
authors.affiliation: Department of Biosystems, MeBioS Division, KU Leuven, Kasteelpark Arenberg 30 Box 2456, 3001 Leuven, Belgium. Electronic address: mohammad.godarzi@gmail.com.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Goodarzi
authors.affiliation: Department of Chemistry "U. Schiff", University of Florence, Via U. Schiff 6, 50019 Sesto Fiorentino, Florence, Italy. Electronic address: claudia.caprini@unifi.it.
authors.forename: Claudia
authors.initials: C
authors.lastname: Caprini
authors.affiliation: Department of Pharmacy and Biotechnology, University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy. Electronic address: roberto.gotti@unibo.it.
authors.forename: Roberto
authors.initials: R
authors.lastname: Gotti
authors.affiliation: Department of Chemistry "U. Schiff", University of Florence, Via U. Schiff 6, 50019 Sesto Fiorentino, Florence, Italy. Electronic address: sandra.furlanetto@unifi.it.
authors.forename: Sandra
authors.initials: S
authors.lastname: Furlanetto
mesh_terms: D000073738:2-Hydroxypropyl-beta-cyclodextrin; D002110:Caffeine / Q000032:analysis; D002392:Catechin / Q000032:analysis; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D016000:Cluster Analysis; D016002:Discriminant Analysis; D005504:Food Analysis; D048088:Informatics / Q000379:methods*; D025341:Principal Component Analysis; D013237:Stereoisomerism; D013662:Tea / Q000737:chemistry*; D013805:Theobromine / Q000032:analysis; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D013662:Tea; D047392:beta-Cyclodextrins; D000073738:2-Hydroxypropyl-beta-cyclodextrin; D002110:Caffeine; D002392:Catechin; D013805:Theobromine
keywords: Capillary Electrophoresis; Classification models; Discriminant analysis; Green tea; Hierarchical cluster analysis; Principal component analysis