title: Development of an improved reverse-phase high-performance liquid chromatography method for the simultaneous analyses of trans-/cis-resveratrol, quercetin, and emodin in commercial resveratrol supplements.
abstract: The objectives of the study were to develop a reverse-phase high-performance liquid chromatography method for the simultaneous analyses of trans-/cis-resveratrol, emodin, and quercetin and to determine the concentrations of these polyphenols in 28 resveratrol supplements. Samples were separated within 15 min in a C18 reversed-phase column using mobile phases containing 0.1% formic acid and methanol/0.1% formic acid. The calibration graphs for all four compounds were linear from 0.1 to 410 μg/mL (r2=0.99). The concentration of resveratrol as stated on the labels was often different from the analytical results, with 21 and 11% of the total supplements having low or high values, respectively. Many of the supplements also contained variable but generally low levels of emodin, a compound known to cause diarrhea. The proposed method is a rapid, sensitive, accurate, and cost-effective procedure that can be used for the simultaneous quantification of four polyphenols in resveratrol supplements.
authors.affiliation: Richardson Centre for Functional Foods and Nutraceuticals, University of Manitoba , 196 Innovation Drive, Winnipeg, Manitoba R3T 2N2, Canada.
authors.forename: Jaclyn M
authors.initials: JM
authors.lastname: Omar
authors.forename: Haifeng
authors.initials: H
authors.lastname: Yang
authors.forename: Suzhen
authors.initials: S
authors.lastname: Li
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Marquardt
authors.forename: Peter J H
authors.initials: PJ
authors.lastname: Jones
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D056148:Chromatography, Reverse-Phase / Q000379:methods; D019587:Dietary Supplements / Q000032:analysis*; D004642:Emodin / Q000737:chemistry*; D007536:Isomerism; D011794:Quercetin / Q000737:chemistry*; D000077185:Resveratrol; D013267:Stilbenes / Q000737:chemistry*
chemical_list: D013267:Stilbenes; D011794:Quercetin; D004642:Emodin; D000077185:Resveratrol