title: Ingredient Consistency of Commercially Available Polyphenol and Tocopherol Nutraceuticals.
abstract: Label claims of vitamin E succinate and polyphenolic nutraceuticals are assessed. A validated HPLC method was utilized to assess vitamin E succinate products. Three novel LC/MS methods were used to assess the polyphenols, pterostilbene, phloretin, and myricetin, in dietary supplements. The amount of vitamin E succinate varied from 0-130% of the stated label content with two products containing vitamin E acetate rather than vitamin E succinate. Expected polyphenols were found in 7 of the 8 supplement products. None of the polyphenol supplements contained content within 100-120% of label claims. The present study indicates a lack of uniformity in nutraceutical products.
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Pullman, WA 99164-6534, USA. connie.remsberg@email.wsu.edu.
authors.forename: Connie M
authors.initials: CM
authors.lastname: Remsberg
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Pullman, WA 99164-6534, USA. renee.good@ucdenver.edu.
authors.forename: Renee L
authors.initials: RL
authors.lastname: Good
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Pullman, WA 99164-6534, USA. ndavies@wsu.edu.
authors.forename: Neal M
authors.initials: NM
authors.lastname: Davies
keywords: content analysis; myricetin; nutraceuticals; phloretin; polyphenols; pterostilbene; vitamin E succinate