OBJECTIVE 3.1: Nutritious food: "Maintain an adequate, nutritious, and safe supply of food to meet human nutritional needs and requirements."

STRATEGY 3.1.1: Human nutrition requirements: Determine requirements for nutrients and other food components of children, pregnant and lactating women, adults, and elderly of diverse racial and ethnic backgrounds.

During FY 2001, ARS will

ACCOMPLISHMENTS: Although it is widely believed that components of tea, specifically catechins, may promote a healthy body weight, only a single human study documents this effect. The impact of oolong tea, which is rich in catechins, on energy expenditure and substrate utilization was assessed.

Polyphenolics isolated from blueberries and cranberries protected endothelial cells against stressor induced oxidation and inflammation.

Quercetin, a flavonoid found in many fruits and vegetables, was found to be capable of lowering plasma concentrations as much as 15 percent in rat studies.

IMPACT/OUTCOME: It was found that oolong tea increased energy expenditure relative to water and it was effective in increasing preferential oxidation of fat.

These compounds in blueberries and cranberries may have beneficial actions against the development of vascular diseases and may contribute to the reduction of age-related deficits in neurological impairment.

The data in this study suggests that quercetin may attenuate a post absorptive glucose peak in obese nondiabetic subjects and patients with type 2 diabetes.

ACCOMPLISHMENTS: Lower memory function was associated with lower folate levels and homocysteine levels. Depression was also found to be more common in those with low folate and high homocysteine blood levels.

One approach in using biomarkers of lipid peroxidation to predict the risk of chronic disease is to compare values between healthy and ill subjects. Plasma F2-isoprostanes, biomarkers of lipid peroxidation, were measured in patients with end-stage renal disease on hemodialysis and age/gender-matched health adults. Despite similar vitamin E status, patients had higher F2-isoprostanes, a parameter which correlated with plasma C-reactive protein, a measure of inflammation.

IMPACT/OUTCOME: These findings provide further evidence that inadequate folic acid status and vitamin B12 nutrition are related to cognitive decline and depression in elders.

ACCOMPLISHMENTS: Dysregulation of the immune response is the most significant and reproducible age-related change reported across all species. T lymphocytes from old mice exposed to vitamin E showed significant increase in the ability of nave cells to progress through multiple cell cycles. T lymphocytes exhibit the most dramatic age-related changes.

A transgenic mouse model system is being used to define the molecular role of vitamin A in regulating the development of T-helper cells, which play a central role in modulating the immune response to infectious and inflammatory diseases, as well as cancer.

IMPACT/OUTCOME: This is the first time that a nutrient has been shown to correct a fundamental age-related change in T cells. This finding may have significant implications for improving the overall health status of the aged by improving immune function.

Findings suggest that dietary vitamin A enhances the Th2-mediated responses and thus could improve resistance to enteric infections that require secretory IgA to clear primary infections and protect against reinfection.

STRATEGY 3.1.2: Food composition and consumption: Develop techniques for determining food composition, maintain national food composition databases, monitor the food and nutrient consumption of the U.S. population, and develop and transfer effective nutrition intervention strategies.

During FY 2001, ARS will

ACCOMPLISHMENTS: The survey merger took place January 2002. A pilot study was conducted to assure that the USDA Automated Multiple-Pass Method and related systems integrated into the NHANES Mobile Examination Center "environment" operated successfully so that national data collection using the new USDA instrument would go as scheduled in January 2002. The pilot study was successful with the USDA Multiple-Pass Method and related systems performing without any problems.

IMPACT/OUTCOME: The pilot study was successful.

ACCOMPLISHMENTS: Chromatographic methods have been developed and appropriate standards have been produced which will allow separation and quantization of proanthocyanidins in foods. Data from this project will provide, for the first time, the information necessary to assess dietary intakes of proanthocyanidins and in conjunction with other epidemiology data, begin to determine possible relationships between dietary intake and health outcomes.

An LC-MS procedure for the quantification of beta-carotene and lutein from uniformly-labeled 13C-kale was developed.

IMPACT/OUTCOME: Data from this project provides information necessary to determine possible relationships between dietary and intake and health outcomes.

This method to quantify beta-carotene and lutein was applied to the determination of the phytonutrients in food.

IMPACT/OUTCOME: This database provides estimates of composition for up to 80 components and approximately 6,200 foods.

STRATEGY 3.1.3: Nutritious plant and animal products: Provide input to plant and animal scientists so more nutritious plant and animal products for human consumption may be developed.

During FY 2001, ARS will

ACCOMPLISHMENTS: The eggplant germplasm core collection of the United States was evaluated for fruit phenolic composition and content by ARS researchers at Beltsville, Maryland. These results, publicly available, provide baseline data on eggplant phytonutrient composition and will be utilized by germplasm development programs to characterize the genetic control of eggplant fruit phenolic composition and develop germplasm with improved nutritive value.

Segregating carrot populations varying in orange, purple, yellow, and red root color were grown in California (two locations), Wisconsin, and Washington by ARS scientists in Wisconsin. PCR-based markers were evaluated for three genes of the carotenoid biosynthetic pathway and one gene for anthocyanin biosynthesis. Stocks with sweet, mild flavor and high pigment content were identified. Further breeding and nutritional feeding studies are underway with these populations.

ARS researchers in Charleston, South Carolina, have shown significant genetic variation for head calcium and magnesium concentrations among broccoli hybrids and inbreds, as well as for several key chemoprotective agents in broccoli that may protect humans against certain cancers.

IMPACT/OUTCOME: Public and private researchers will be able to use the results of this research in breeding new varieties as it lays the groundwork for genetic improvement of vegetables with enhanced levels of nutritional and health-promoting constituents.

ACCOMPLISHMENTS: Fortification of foods with iron can alleviate iron deficiency, but these programs are expensive and not sustainable in many parts of the world. In collaboration with International Food Policy Research Institute (IFPRI), the International Rice Research Institute (IRRI), the Center for Improvement of Maize and Wheat (CIMMYT) and the International Institute of Tropical Agriculture (IITA), ARS scientists at Ithaca, New York, began identifying genotypes of staple food crops (rice, wheat and corn) that are higher in bioavailable iron content. Using a simulated digestion/cell culture model, 15 genotypes of rice, 20 genotypes of wheat, and a portion of 70 genotypes of corn produced in 3 different agricultural zones of Nigeria were screened. Additionally, in cooperation with CIAT and CIMMYT, iron- and zinc-dense lines of beans and wheat are being tested for bioavailable levels of iron and zinc. Identified micronutrient-dense genotypes of these staple food crops will be advanced in the breeding programs at IRRI, CIAT and CIMMYT.

Ferritin is the major storage form of Fe in all aerobic organisms including plants, animals and humans and is being studied by ARS scientists at Ithaca, New York. Genetically engineered rice transformants have been developed that accumulates more iron in the endosperm of rice grain as phytoferritin. However, it is not known if the iron in phytoferritin is bioavailable to humans. Results of studies with humans show that iron in soybeans that contain high levels of phytoferritin is highly bioavailable to iron-depleted women.

IMPACT/OUTCOME: This research will provide nutritionists, plant breeders, and biotechnologists with insight to improve the nutritional quality of foods worldwide and alleviate the severe effects of malnutrition for millions of people.

ACCOMPLISHMENTS: Tomatoes contain important health-promoting compounds known as lycopenes. ARS researchers at the Western Regional Research Center in Albany, California, demonstrated preliminary results show that extremely low concentrations of a bioregulator significantly increase lycopene production in tomato fruit when applied to tomato seeds prior to planting. These scientists have also identified and isolated three key ripening-associated genes in lycopene-rich tomatoes.

The development of gene chips for the study of changes in gene expression on a global scale is a powerful new tool for studying plant function at molecular levels and for the identification of new genes involved in specific processes. A tomato gene chip was developed by ARS researchers at Ithaca, New York, that contains 2,800 nonredundant gene sequences associated with the nutrient quality and accumulation of health promoting compounds such as antioxidants in ripening fruit. This chip is now being used to better understand and identify key genes regulating the accumulation of essential nutrients and health promoting compounds in ripening fruits, in order to develop more nutritious and healthy plant foods.

IMPACT/OUTCOME: The development of this seed treatment method and the identification of genes associated with phytonutrient accumulation puts researchers a significant step closer to being able to develop new tomato varieties with high lycopene content, as well as enhancing the lycopene content during the production of existing varieties.