1. Department of Food Science, College of Food Engineering, State University of Campinas, P.O. Box 6177, 13083-970, Campinas, São Paulo, Brazil; Cátedra de Fitoquímica, Instituto de Estudios Vegetales Dr. A. R. Sampietro, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, 4000 San Miguel de Tucumán, Argentina; and Center for Oral Biology and Eastman Deparment of Dentistry, University of Rochester Medical Center, Rochester, New York 14642