1a. Objectives (from AD-416):
ARS is interested in developing spectral fingerprinting methods for characterization and authentication of botanical dietary supplements. The Cooperator is interested in developing analytical methods for botanical materials. It has agreed to fund a 5-year proposal (FY2009-FY2013) submitted by FCMDL entitled “Development of spectral fingerprinting methods for rapid characterization and authentication of botanical dietary supplements”.
1b. Approach (from AD-416):
FCMDL will develop methods for identification of Panax quinquefolium and Scutellaria lateriflora and characterization of authentic green tea, turmeric, cranberries, and opuntia (prickly cactus). Emphasis will continue to given to determining the efficacy of UV for identity methods. FCMDL will examine the many processed forms of P. ginseng. FCMDL will develop retention alignment programs that will allow application of pattern recognition to liquid chromatographic profiles in collaboration with the Ohio University (Athens,OH).
3. Progress Report:
In collaboration with the Office of Dietary Supplements at NIH, FCMDL is establishing an in-house database for phytochemical compounds, such as anthocyanins and other flavonoids, using high resolution mass spectrometry. To date, more than 300 compounds have been positively identified using the scientific literature and authentic reference materials. The new database contains their exact mass, chemical formula, structure, full mass spectra, and molecular absorption spectra. The database will be used to facilitate identification of chemical components in future analysis of food materials and will save significant time and resources. American ginseng (Panax quinquefolius) is far more expensive than Asian ginseng (P. ginseng) on the world market. Consequently, adulteration of American by Asian ginseng is common. FCMDL has developed an analytical method using a simple methanol-water extraction and direct analysis using flow injection mass spectrometry that can detect as little as 2% adulteration by Asian ginseng. In addition, a software model was developed that permitted adulterated spectra to be predicted based on the spectra of the pure American and Asian ginseng. Anthocyanins are common flavonoids that have been linked to resistance to cancer, diabetes, infections, inflammation, and neurological diseases. Scientists at USDA in Beltsville, MD, analyzed purple radishes (Raphanus sativus L.), a plant bred to provide high anthocyanin content, by high performance liquid chromatography ( HPLC) with high resolution mass detection (HRMS). The method detected 57 acylated anthocyanins, 45 for the first time. This study showed the presence of a large variety of anthocyanins and the necessity of HPLC-HRMS to provide the sensitivity and specificity for their identification. The popularity of botanical supplements to augment the US diet has provided a strong economic impetus for adulteration. Ginkgo biloba extract is a frequently used supplement that purportedly provides enhanced cognitive function. Scientists at USDA in Beltsville, MD, measured 22 flavonol glycosides in three NIST reference materials (SRM 3246, 3247, and 3248) and 20 commercially available supplements using HPLC-MS. Half of the commercial supplements were found to be adulterated with one of two inexpensive compounds (quercetin or quercetin rutinoside). Analysis was easily accomplished with a simple methanol-water extraction and direct analysis by UV spectrophotometry. This method provides the analyst with an inexpensive method for detecting adulterants. Samples of ten plants (sorghum, black beans, red beans, purple grape skin powder, soybeans, black cohosh, eggplant, corn flour, and broccoli) were extracted with three solvents (hexane, ethyl acetate, and methanol-water. All samples will be analyzed by HPLC-MS. This project will elucidate the extraction steps necessary for metabolomic profiling of plant materials.