ABSTRACT
Polyphenols are a large family of compounds having more than two phenolic OH groups in their structure, although simple phenolic acids and alcohols are also included in the group and are widely distributed in nature, especially in plants (Halvorsen et al., 2002; Shahidi and Ho, 2005). Epidemiologically, it is suggested that the consumption of polyphenol-rich foods or beverages is associated with the prevention of diseases, cancer, and aging. Now people are living longer, issues of cardiovascular protection, anticancer effects, and neurodegenerative disease prevention are attracting particular attention (Chen et al., 2008; Ness and Powles, 1997; Visioll and Hagen, 2007). Indeed, various reports on polyphenols have been published, discussing their essential antioxidant pro perties (Lopez-Velez et al., 2003), cardiovascular protection (Tuoie et al., 2007; Yung et al., 2008), anticancer effects (Steinmetz and Potter, 1996), antidiabetic properties (Venables et al., 2008), reduction in cataract development (Chethan et al., 2008), anti-in ammatory effect (Rahman, 2006), and so on. These are described in several review articles (D’Archivio et al., 2007; Prasain and Barnes, 2007; Scalbert and Willamson, 2000; Singh et al., 2008; Willamson and Manach, 2005; Yang et al., 2008). Fruits, vegetables, spices, and herbs are major sources of dietary polyphenols, and are therefore attracting attention as major foods which play a critical role in human health promotion and disease prevention.
