2007 Annual Report 1a.Objectives (from AD-416) To determine in vitro the antioxidant potential of approximately 50 botanical products identified by the National Center for Complementary and Alternative Medicine. 1b.Approach (from AD-416) Using well established in vitro assays for antioxidant action of foods and phytochemicals, the anitoxidant potency of the botanicals will be calculated from relevant dose-response experiments in each assay of the screening panel based upon the concentration of total phenolic compounds in each plant. Quality control processes and nutrient references (e.g. ascorbic acid, beta-carotene, alpha tocopheral, and epigallocatechin gallate) will be proposed for this study. 3.Progress Report This report serves to document work conducted on the project High-Throughput In Vitro Screening of Botanical Products for Antioxidant Capacity and Bioactivity originating from a Reimbursable Interagency Agreement between USDA Agricultural Research Service and NIH National Center for Complementary and Alternative Medicine (NCCAM), Agreement number 60-1950-5-026, project number 1950-51000-065-03R. The research is being carried out in this project by Tufts University investigators in the USDA Human Nutrition Research Center on Aging under an Assistance Type Cooperative Agreement #59-1950-7-735. The project is being monitored by ARS via onsite discussions with the Tufts investigator who is in regular communication with the NCCAM Primary investigator, quarterly financial reports and annual performance reports to ARS. Additional details of research can be found in the report for the in-house associated project 1950-51000-065-00D, Dietary Antioxidants, Aging and Oxidative Stress Status. Using in vitro assays for the antioxidant action of foods and phytochemicals, the Antioxidants Research Laboratory is determining the antioxidant potential of 50 botanical products. The antioxidant potential is being calculated from relevant dose-response experiments in each assay of the screening panel based upon the concentration of total phenolic compounds in each plant. Quality control processes and nutrient references, e.g., ascorbic acid, beta-carotene, alpha-tocopherol, and epigallocatechin gallate are included in the screening panel. During the last year, 30 assays have been established, calibrated, and validated for this project, including those for the assessment of direct quenching of reactive haloid, oxygen, and nitrogen species as well as total antioxidant capacity by the constituents of the test material. In addition, the panel employs cell cultures designed to assess parameters of apoptosis, cell growth arrest, cell proliferation, cytotoxicity, and necrosis and well as induction of phase 2 detoxification enzymes.