To appreciate and to understand important minimal constituents of plant foods to our health, the composition of bioactive phytochemicals in fruits, vegetables, and beverages and their functional properties are being studied. We have been working for several years on flavonoids in apples, grapes, cherries, peaches, plums, and onions. In cooperation with scientists at Cornell and at Seoul National University, we have been working on antioxidant and anticancer activities of these and other commodities. Extraction and isolation using various solvents, low and high performance liquid chromatography, thin-layer chromatography, UV spectrophotometric, mass-spectrometric methods, and other methods have been employed. Numerous polyphenolic compounds were analyzed and various new compounds are being identified. Cultivar variations in flavonoid constituents, location of specific flavonoids within a fruit, and their antioxidant and anticancer activities are our present interests. We have developed a simple and reliable antioxidant activity measurement method based on vitamin C equivalent antioxidant capacity (VEAC) in weight basis. Antioxidant and antiinflammatory capacity of various foods and the combined effects of several phytochemicals are being studied. We found that plums, grapes, cherries, and apples have strong antioxidant activity. Apples with skin-on showed more phenolic content and more total oxyradical-scavenging capacity than apples without skin. Some American grapes (Vitis labrascana) showed stronger antioxidant activity than that of European grapes (Vitis vinifera). Quercetin, an important phytochemical in apples, showed a stronger antioxidant capacity that that of vitamin C at the same molar weight basis. Apple phenolics also inhibited colon-cancer cell and liver-tumour cell proliferation in vitro test.

The following publications are related to phytochemicals published from this laboratory.

Lee, C. Y. and A. W. Jaworski. Phenolic compounds in New York grapes. 10th Annual Meeting of American Society of Enology and Viticulture Eastern Section. Abstract # 7. 1985.

Jaworski, A. and C. Y. Lee. An analytical method for phenolic compounds in grapes. 46th Annual Meeting of Institute of Food Technologists. Abstract #153. 1986.

Lee, C. Y. and A. Jaworski. Phenolic compounds in white grapes grown in New York. American Journal of Enology and Viticulture. 338:277-281. 1987.

Jaworski, A. and C. Y. Lee. Fractionation and HPLC determination of grape phenolics. Journal of Agricultural and Food Chemistry. 35:257-259. 1987.

Oleszek, W., C. Y. Lee, A. W. Jaworski, and K. R. Price. Identification of some phenolic compounds in apples. Journal of Agricultural and Food Chemistry. 36:430-432. 1988.

Lee, C. Y., W. Oleszek, A. W. Jaworski, and K. R. Price. Isolation and identification of some phenolic compounds in apple. The Pittsburgh Conference, Abstract #463, New Orleans, 1988.

Lee, C. Y. and A. W. Jaworski. Major phenolic compounds in ripening white grapes. American Journal of Enology and Viticulture 40(1):43-46. 1989.

Burda, S., W. Oleszek, and C. Y. Lee. Phenolic compounds and their changes in apple during maturation and cold storage. Journal of Agricultural and Food Chemistry. 38: 945-948. 1990.

Lee, C. Y. and J. Oszmianski. Antioxidant effect of phenolic compounds on carotene in vegetables. 199th National Meeting of American Chemical Society, Abstract AGFD #12. Boston, MA. 1990.

Lee, C. Y. and M. R. McLellan. Effect of cultivar and composition of phenolics on browning of apples. IFT Annual Meeting, Abstract # 558. Anaheim, CA. 1990.

Oszmianski, J. and C. Y. Lee. Isolation and HPLC determination of phenolic compounds in red grapes. American Journal of Enololgy and Viticulture. 41(3):204-206. 1990.

Oleszek, W., C. Y. Lee and K. R. Price. Apple phenolics and their contribution to enzymatic browning reactions. Acta Societatis Botanicorum Poloniae 58(20): 273-283, 1990.

Lee, C. Y. and A. W. Jaworski. Identification of some phenolics in white grapes. American Journal of Enolology and Viticulture. 41(1): 87-89. 1990.

Ho, C.-T., Lee, C. Y. and Huang, M. T. "Phenolic Compounds in Food and Their Effects on Health I: Analysis, Occurrence, and Chemistry." American Chemical Society Symposium Series 506, 315 pages, 1992. American Chemical Society, Washington, D. C.

Huang, M. T., Ho, C.-T. and Lee, C. Y. "Phenolic Compounds in Food and Their Effects on Health II: Antioxidants and Cancer Prevention." American Chemical Society Symposium Series 507, 402 pages, 1992. American Chemical Society, Washington, D. C.

Cheigh, H. S. and C. Y. Lee. Antioxidative characteristics of plant phenolic compounds. Life Science (Korea) 3(1):9-17. 1993.

Park, Y. K. and Lee, C. Y. Analysis of major flavonoids in onions. International Conference of the Groupe Polyphenols. Abstract # P61, Palma de Mallorca, Spain. 1994.

Kim, M. and Lee, C. Y. Effect of carotenes on enzymatic oxidation of chlorogenic acid and tyrosine. International Conference of the Groupe Polyphenols. Abstract # P18, Palma de Mallorca, Spain. 1994.

Lee, C. Y. Phenolic Compounds. In "Encyclopedia of Food Science and Technology." Edited by Y. H. Hui. p 2055-2061 (1991), John Wiley & Sons, NY.

Park, Y. K. and Lee, C. Y. Effects of processing on quercetin and its glucosides in onions. Institute of Food Technologists Annual Meeting, Abstract 12F-8, Atlanta, 1994.

Park, Y. K. and C. Y. Lee. Analysis of major flavonoids in onions. Proceedings of 17th International Conference on Polyphenols. Ed. R. Brouillard, A. Jay and A. Scalbert. p 265-257, 1994.

Park, Y. K. and C. Y. Lee. Changes in quercetin and its derivatives in onions during processing. Mokpo National University Thesis Collection Vol. 15(2): 629-637, 1994.

Lee, C. Y. Food and Health: Natural Antioxidants. Proceedings of Sixth KSEA Northeast Regional Conference. Rutgers University, New Brunswick, N. J. p. 141-143, 1995.

Park. Y. K and C. Y. Lee. Identification of isorhamnetin-4'-glucoside in onions. Journal of Agricultural and Food Chemistry 44:34-36, 1996.

Lee, C. Y., Smith, N. L., De Mas Latrie, I. Antioxidant activity of apples and their contribution to our diet. Institute of Food Technologists Annual Meeting, Abstract Number 34B-50, 1998.

Friedrich, J. E. and C. Y. Lee, HPLC determination of phenolic compounds in cherries. Institute of Food Technologists Annual Meeting Abstract #67-1, p 188, 1997.

Friedrich, J. E. and Lee, C. Y. Phenolic compounds in sweet and sour cherries. International Conference on Polyphenols, Lille, France Abstract # 527, 1998.

Kobayashi, C. K. and Lee, C. Y. Identification and quantification of some phenolic compounds in the flesh and skin of Vitis Labruscana grapes. Institute of Food Technologists Annual Meeting, Chicago. Technical Program Abstract # 48-1, p 115, 1999.

Wang, L. F., Kim, D. M., Kim, S. S., Park, J. D. and Lee, C. Y. Changes in the chemical composition and sensory quality of green tea extracts during processing and storage. Institute of Food Technologists Annual Meeting, Chicago. Technical Program Abstract # 50B-43, p 139, 1999.

Lee, C. Y. Phenolic Compounds. In "Encyclopedia of Food Science and Technology." 2^nd Ed. Edited by J. Francis. John Wiley & Sons, NY. 1999.

Wang, L.F., Kim, D.M. and Lee, C.Y. Effect of heat processing and storage on flavanols in Green tea. Abstract #174. National American Chemical Society Meeting, San Francisco, March 26-30, 2000.

Wang, L. F., Kim, D. M., and Lee, C. Y. Effects of heat processing and storage on flavanols and sensory quality of green tea beverage. Journal of Agricultural and food Chemistry 48(9): 4227-4232, 2000.

Eberhardt, M. V., Lee, C. Y. and Liu, R. H. Antioxidant activity of fresh apples. Nature 405:903-904, June 22, 2000.

Lee, C.Y. and Smith, N.L. Apples: An important source of antioxidants in the American diet. New York Fruit Quarterly 8(2): 15-17, 2000.

Liu, R.H., Eberhardt, M.V. and Lee, C.Y. Antioxidant and antiproliferative activities of selected New York apple cultivars. New York Fruit Quarterly 9(2):15017, 2001.

Lee, K.W., Lee, H.J., Kang, K.S., and Lee, C. Y. Preventive effects of vitamin C on carcinogenesis. The Lancet 359: 172, 2002.

Lee, K. W., Lee, H. J. and Lee, C. Y. Antioxidant activity of black tea vs. green tea. (letter) Journal of Nutrition 132(4): 785, 2002.

Liu, M., Li, X. Q., Weber, C., Lee, C. Y., Brown, J. and Liu, R. H. Antioxidant and antiproliferative activities of raspberries. Journal of Agricultural and food chemistry 50:2926-2930, 2002.

Lee, C. Y., Lee, C. H. and Kwon, T. W. Future of Foods: Harmonization of eastern and western food systems. The World of Food Science Vol 3, No 1. (An Online Food Science and Technology, IUFoST-IFT). www.worldfoodscience.org , May 6,2002.

Lee, Ki Won and Lee, C. Y. Vitamins, diet, and cancer prevention. (letter). American Journal of Clinical Nutrition 75:1122-1123, 2002.

Kim, D. O., Lee, K. W., Lee, H. J. and Lee, C. Y. Vitamin C equivalent antioxidant capacity (VCEAC) of phenolic phytochemicals. Journal of Agricultural and Food Chemistry 50:3713-3717, 2002.

Wang, Li-Fei, Kim, D. M., and Lee, C. Y. Interaction of flavanols in green tea extract during heat processing and storage. Food Science and Biotechnology, 11(6):608-612, 2002.

Kim, D. O., Jeong, Seung Weon, and Lee, C. Y. Antioxidant capacity of phenolic phytochemicals from various cultivars of plums. Food Chemistry 81: 321-326, 2003.

Wang, L. F., Kim, D. M., Park, J. D. and Lee, C. Y. Various antibrowning agents and green tea extract during processing and storage. Journal of Food Processing and Preservation 27:213-225, 2003.

Kim, D. O., Lee, K. W., Chun, O. K., Lee, H. J., and Lee, C. Y. Antiproliferative activity of polyphenolics in plums. Food Science & Biotechnology (Korea) 12:399-402, 2003.

Kim, D. O., Chun, O. K., Kim, Y. J., Moon, H. Y. and Lee, C. Y. Quantification of polyphenolics and their antioxidant capacity in fresh plums. Journal of Agricultural and Food Chemistry 51:6509-6515, 2003.

Lee, K. W., Kim, Y. J., Kim, D. O., Lee, H. J. and Lee, C. Y. Major phenolics in apple and their contribution to the total antioxidant capacity. Journal of Agricultural and Food Chemistry 51:6516-6520, 2003.

Chun, O. K., Kim, D. O., Moon, H. Y., Kang, H. G., and Lee, C. Y. Contribution of individual polyphenolics to total antioxidant capacity of plums. Journal of Agricultural and Food Chemistry 51: 7240-7245, 2003.

Lee, K. W., Kim, Y. J., Lee, H. J., and Lee, C. Y. Cocoa has more phenolic phytochemicals and a higher antioxidant capacity than teas and red wine. Journal of Agricultural and Food Chemistry 51 7292-7295, 2003.

Chun, O. L., Kim, D. O., Lee, C. Y. Superoxide radical scavenging activity of the major polyphenols in fresh plums. Journal of Agricultural and Food Chemistry 51: 8067-8072, 2003.

Lee, K. W., Lee, H. J., Surh, Y. J., and Lee, C. Y. Vitamin C and chemoprevention: reappraisal. American Journal of Clinical Nutrition 78: 1074-1078, 2003.