Simple and rapid simultaneous profiling of minor components of honey by size exclusion chromatography (SEC) coupled to ultraviolet diode array detection (UV-DAD), combined with chemometric methods

• Published in: Journal of pharmaceutical and biomedical analysis 2012-01, Vol.58 (25), p.193-199
• Main Authors: Beretta, Giangiacomo, Fermo, Paola, Maffei Facino, Roberto
• Format: Article
• Language: English
• Subjects: absorption; Analysis; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Calibration; Castanea; Chemometrics; Chromatography, Gel - methods; cluster analysis; enzymes; flowers; Flowers - chemistry; Fundamental and applied biological sciences. Psychology; General pharmacology; glycosides; Honey; Honey - analysis; Medical sciences; Multivariate Analysis; nectar; Pharmacology. Drug treatments; Principal Component Analysis; proteins; provenance; Quality Control; rain forests; secondary metabolites; Size exclusion chromatography; terpenoids; trees; Ultraviolet Rays; UV-DAD
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/j.jpba.2011.09.006

► A HPLC-DAD methodology for honey minor components analysis is presented. ► UV absorbing species from low to high molecular weight can be easily profiled. ► Several information can be drawn by visual and chemometric evaluation of the results. This paper discusses the importance of profiling UV-responsive components, properly integrated with chemometric techniques, in detecting indicative parameters for quality control of honey. The minor components in honeys of different botanical and geographical origins were investigated by size SEC-UV-DAD. We diluted honey with mobile phase before injection into the chromatographic apparatus and a single chromatographic run gave a fast profile of high- (proteins and enzymes), intermediate- (e.g. terpenoid glycosides in lime tree honey) and low-molecular-weight components (secondary metabolites, e.g. kynurenic acid in chestnut honey). The analysis of a total number of 32 honey samples from different regions (Italy, Western Balkan countries, Brazil, Cameroon, Kenya) and of different botanical origins (herbal flower and arboreal flower nectars/honeydews) showed peculiar and characteristic distribution of these markers, which were basically related to their floral origin. Chemometric examination carried out using principal component analysis (PCA) and hierarchical cluster analysis (HCA) of the chromatograms (RT vs. absorption) detected four main clusters in which the groups of (i) chestnut honeys, (ii) honeys from rain forests and (iii) counterfeit/adulterated honeys were clearly separated from the main group of flower nectar honeys. The method is fast, requiring minimal sample handling, and the chromatographic data can be analyzed by multivariate statistical techniques to obtain descriptive information about the honey's quality and composition.