ORGANIC ACID AND FLAVONOL PROFILES
IN VACCINIUM BERRY DIETARY SUPPLEMENT
STANDARD REFERENCE MATERIALS (SRMs)
Melissa S. Meaney, Lane C. Sander, and Katherine E. Sharpless
A variety of dietary supplements are manufactured and marketed globally to promote human health and enhance the quality of life. To ensure safety of consumers, taxonomically authentic botanical reference materials with assigned concentrations of active and marker compounds, nutrients, and potential contaminants are needed in the dietary supplement community to provide a close matrix match for analytical measurements. Several SRMs are being produced that include suites of powdered botanical, extract, and finished product forms of each dietary supplement.
Vaccinium species (e.g., cranberries, blueberries, bilberries) are used in dietary supplement formulations to promote urinary tract health and to reduce the incidence of various cancers and cardiovascular diseases. The potential health benefits of these berries are directly related to the concentrations of antioxidants, mainly anthocyanins and flavonols. The relative amounts of other compounds such as organic acids can significantly affect the organoleptic properties of berries and their products.
Methods for the determination of the organic acid, anthocyanidin, and flavonol content of a number of Vaccinium berry SRMs are under development. Following aqueous extraction, concentrations of eight organic acids have been determined by liquid chromatography (LC) with absorbance detection at 210 nm and by ion chromatography with conductivity detection. An additional quantitation method has been developed using LC with mass spectrometric detection. Six anthocyanins and two flavonols contained in the SRMs were simultaneously extracted and hydrolyzed to the aglycone forms by a 24-hour Soxhlet extraction in acidic methanol. The aglycone concentrations have been determined by LC with absorbance detection at 525 nm and 366 nm, respectively.
These SRMs will assist dietary supplement manufacturers in achieving consistent product formulations of known potency and accurate product labels. In addition, the methods used for certification of organic acid, anthocyanidin, and flavonol concentrations in the SRMs will be useful to analysts in the dietary supplement industry.
Author: Melissa S. Meaney
Mentor: Lane C. Sander
Division: Analytical Chemistry Division (ACD, 839)
Laboratory: Chemical Science and Technology Laboratory (CSTL)
Address: Building 227, Room B144
Mail Stop: 8392
Membership in Sigma Xi: Neither author nor mentor