title: Discrimination and classification techniques applied on Mallotus and Phyllanthus high performance liquid chromatography fingerprints.
abstract: Mallotus and Phyllanthus genera, both containing several species commonly used as traditional medicines around the world, are the subjects of this discrimination and classification study. The objective of this study was to compare different discrimination and classification techniques to distinguish the two genera (Mallotus and Phyllanthus) on the one hand, and the six species (Mallotus apelta, Mallotus paniculatus, Phyllanthus emblica, Phyllanthus reticulatus, Phyllanthus urinaria L. and Phyllanthus amarus), on the other. Fingerprints of 36 samples from the 6 species were developed using reversed-phase high-performance liquid chromatography with ultraviolet detection (RP-HPLC-UV). After fingerprint data pretreatment, first an exploratory data analysis was performed using Principal Component Analysis (PCA), revealing two outlying samples, which were excluded from the calibration set used to develop the discrimination and classification models. Models were built by means of Linear Discriminant Analysis (LDA), Quadratic Discriminant Analysis (QDA), Classification and Regression Trees (CART) and Soft Independent Modeling of Class Analogy (SIMCA). Application of the models on the total data set (outliers included) confirmed a possible labeling issue for the outliers. LDA, QDA and CART, independently of the pretreatment, or SIMCA after "normalization and column centering (N_CC)" or after "Standard Normal Variate transformation and column centering (SNV_CC)" were found best to discriminate the two genera, while LDA after column centering (CC), N_CC or SNV_CC; QDA after SNV_CC; and SIMCA after N_CC or after SNV_CC best distinguished between the 6 species. As classification technique, SIMCA after N_CC or after SNV_CC results in the best overall sensitivity and specificity.
authors.affiliation: Department of Analytical Chemistry and Pharmaceutical Technology (FABI), Center for Pharmaceutical Research (CePhaR), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, B-1090 Brussels, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Viaene
authors.affiliation: Department of Analytical Chemistry and Pharmaceutical Technology (FABI), Center for Pharmaceutical Research (CePhaR), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, B-1090 Brussels, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Goodarzi
authors.affiliation: Department of Analytical Chemistry and Pharmaceutical Technology (FABI), Center for Pharmaceutical Research (CePhaR), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, B-1090 Brussels, Belgium; Université Libre de Bruxelles (ULB), Institute of Pharmacy, Laboratory of Instrumental Analysis and Bioelectrochemistry, Campus Plaine CP205/6, Boulevard du Triomphe, B-1050 Brussels, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Dejaegher
authors.affiliation: Department of Analytical Chemistry and Pharmaceutical Technology (FABI), Center for Pharmaceutical Research (CePhaR), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, B-1090 Brussels, Belgium.
authors.forename: C
authors.initials: C
authors.lastname: Tistaert
authors.affiliation: Institute of Marine Biochemistry, Vietnamese Academy of Science and Technology (VAST), Hoang Quoc Viet 18, Hanoi, Viet Nam.
authors.forename: A
authors.initials: A
authors.lastname: Hoang Le Tuan
authors.affiliation: Institute of Marine Biochemistry, Vietnamese Academy of Science and Technology (VAST), Hoang Quoc Viet 18, Hanoi, Viet Nam.
authors.forename: N
authors.initials: N
authors.lastname: Nguyen Hoai
authors.affiliation: Institute of Marine Biochemistry, Vietnamese Academy of Science and Technology (VAST), Hoang Quoc Viet 18, Hanoi, Viet Nam.
authors.forename: M
authors.initials: M
authors.lastname: Chau Van
authors.affiliation: Department of Pharmacognosy, Unité CHAM 72.30, Ecole de Pharmacie, Université Catholique de Louvain, Av. E. Mounier, 72, B-1200 Bruxelles, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Quetin-Leclercq
authors.affiliation: Department of Analytical Chemistry and Pharmaceutical Technology (FABI), Center for Pharmaceutical Research (CePhaR), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, B-1090 Brussels, Belgium. Electronic address: yvanvdh@vub.ac.be.
authors.forename: Y
authors.initials: Y
authors.lastname: Vander Heyden
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D016002:Discriminant Analysis; D036461:Mallotus Plant / Q000737:chemistry* / Q000145:classification; D029803:Phyllanthus / Q000737:chemistry* / Q000145:classification; D010936:Plant Extracts / Q000737:chemistry / Q000145:classification; D010946:Plants, Medicinal / Q000737:chemistry* / Q000145:classification; D012044:Regression Analysis
chemical_list: D010936:Plant Extracts
keywords: Chromatographic fingerprinting; Discrimination and classification techniques; Herbal extracts; Supervised and unsupervised data analysis