1a. Objectives (from AD-416):
Objective 1: Develop and evaluate procedures for quantitative extraction and/or fractionation of food materials by polarity. Sub-objective 1.A.: Develop an extraction procedure for sequential fractionation of the major groups of components from plant materials. Sub-objective 1.B.: Develop optimized extraction procedures for accurate quantification of individual phytochemicals in plant materials. Objective 2: Develop and evaluate spectral fingerprinting and chromatographic profiling methods to characterize components in lipid soluble, water soluble, and intermediate fractions of food materials. Sub-objective 2.A.: Develop spectral fingerprinting methods for identification of plant materials and individual components using direct analysis (no prior chromatographic separation) and pattern recognition algorithms. Sub-objective 2.B.: Develop chromatographic profiling methods for identification and quantification of individual components in plant materials. Objective 3: Develop methods to determine variability of biologically active components in food materials through profiles and/or fingerprints. Temporary Objectives: Objective 1: Conduct an independent and outside evaluation of the IT capabilities of the Food Composition and Methods Development Laboratory coordinated with the Nutrient Data Laboratory and the Food Surveys Research Group; include an assessment of whether cloud computing or local data storage is the optimal approach for the next 5-10 years of anticipated data collection, storage, and dissemination. Objective 2: Implement changes to update and modernize the IT infrastructure of the Food Composition and Methods Development Laboratory that links to the Nutrient Data Laboratory and Food Surveys Research Group.
1b. Approach (from AD-416):
Objective 1: Methods will be developed for the quantitative extraction of macro and micro components from plant materials using commercial, high pressure/temperature extraction instrumentation. Soybeans will be tested initially as they contain both lipid soluble and highly polar molecules of health interest. Sequential and parallel extraction will be investigated. Extracted materials will be characterized using liquid chromatography with diode array and electrospray ionization/mass spectrometric detection (LC-DAD-ESI/MS). The new method will be applied to foods and botanical materials. In addition, optimized methods will be developed for specific families of compounds such as water-soluble vitamins, lipid-soluble vitamins, phenolic acids, and flavonoids. Objective 2: Spectral fingerprinting methods will be developed based on ultraviolet and visible molecular absorption (UV/Vis), infrared (IR), near-infrared (NIR), and mass spectrometric (MS) detection. The overlapping complex spectra will be interpreted using pattern recognition programs. The patterns will be used to determine the sensitivity of the different detection systems for discriminating between plant materials based on genera, species, variety, growing year, growing site, and processing conditions. These methods will be developed using 3 food materials and 3 botanical supplement materials. Repeat samples will be examined over a period of years to determine the stability of the spectra and the ability to compare spectra of new materials to archived spectra. The phenolic and vitamin content of the plant materials will also be determined using chromatographic profiling using LC-DAD-ESI/MS. This will make it possible to determine which compounds are contributing most to differences arising from the various growing factors. Objective 3: The spectral fingerprints can be used with nested analysis of variance to determine the relative variance contributed by each growing factor: species, variety, site, year, plant-to-plant variation, and analytical uncertainty. Samples will be obtained from collaborators across the country and representing a variety of foods and botanical supplements. UV/Vis, IR, and NIR spectra will provide variance data for the integrated chemical composition of the plant materials and MS will provide variance data for specific masses and, with the assistance of chromatographic profiling, specific compounds of health interest. Temporary Approaches: Approach 1: Submit names of individuals to the BHNRC with expertise to evaluate existing and future needs for evaluating food composition data arising from analysis in the laboratory. Assessment will include how to work more effectively in sharing compositional information across the various laboraties within the BHNRC. Approach 2: Replace as needed hardware and software needed to evaluate food composition information generated by the FCMDL and for sharing quality compositional information with the NDL and the FSRG.
3. Progress Report:
In collaboration with Thermo Scientific and support from the Office of Dietary Supplements (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. Proanthocyanins are found most notably in chocolate, cranberries, and grape seed and have purported health benefits. Data suggests that the proanthocyanin metabolites are absorbed in the large intestine following digestion by gut bacteria. In this study, pigs were fed diets supplemented by cranberry or grape seed extracts. The extracts have been carefully analyzed and metabolomics analysis of the urine and blood samples is proceeding. Whole wheat flour from five wheat cultivars was evaluated for phenolic, carotenoid, and tocopherol compositions as well as anti-inflammatory and antiproliferative activities against HT-29 cells. The ferulic acid content ranged from 452 to 731 µg/g among the five cultivars and was primarily present in a bound insoluble form. The results showed that whole wheat flours of these five cultivars varied significantly with respect to their content of these bioactive compounds.
Chen, P., Luthria, D.L., Harrington, P.B., Harnly, J.M. 2011. Discrimination among Panax species using spectral fingerprinting. Journal of the Association of Official Analytical Chemists. 94:1411-1421.