title: Validated method for the analysis of goji berry, a rich source of zeaxanthin dipalmitate.
abstract: In the present study an HPLC-DAD method was developed for the determination of the main carotenoid, zeaxanthin dipalmitate, in the fruits of Lycium barbarum. The aim was to develop and optimize an extraction protocol to allow fast, exhaustive, and repeatable extraction, suitable for labile carotenoid content. Use of liquid N2 allowed the grinding of the fruit. A step of ultrasonication with water removed efficiently the polysaccharides and enabled the exhaustive extraction of carotenoids by hexane/acetone 50:50. The assay was fast and simple and permitted the quality control of a large number of commercial samples including fruits, juices, and a jam. The HPLC method was validated according to ICH guidelines and satisfied the requirements. Finally, the overall method was validated for precision (% RSD ranging between 3.81 and 4.13) and accuracy at three concentration levels. The recovery was between 94 and 107% with RSD values <2%, within the acceptable limits, especially if the difficulty of the matrix is taken into consideration.
authors.affiliation: Department of Chemistry, Building of Pharmaceutical Sciences, University of Florence , Via Ugo Schiff 6, 50019 Sesto Fiorentino (FI), Firenze, Italy.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Karioti
authors.forename: Maria Camilla
authors.initials: MC
authors.lastname: Bergonzi
authors.forename: Franco F
authors.initials: FF
authors.lastname: Vincieri
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Bilia
mesh_terms: D002338:Carotenoids / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005638:Fruit / Q000737:chemistry; D032305:Lycium / Q000737:chemistry*; D010936:Plant Extracts / Q000032:analysis*; D011786:Quality Control; D065146:Zeaxanthins / Q000032:analysis*
chemical_list: D010936:Plant Extracts; D065146:Zeaxanthins; D002338:Carotenoids
keywords: Lycium barbarum; carotenoid exhaustive extraction; quality control; validated HPLC-DAD