Polyphenolic content and antioxidant activity of faba bean genotypes with differing seed coat colours.

Plants synthesize phenolic compounds during normal development and while responding to changing environments such as stress, ultraviolet light, wound, reactive species and diseases (Agrios et al., 2005). Phenolics also provide different characteristics such as colour and taste to plants (Streit et al., 2007) and are becoming increasingly known for their human health benefits. For example, phenolic compounds contribute to antioxidant activities and can potentially prevent several ailments including neurological diseases (Dixon & Paiva, 1995), cancers (Meijia et al., 1999) and hypertension (Belinky et al., 1996).Faba beans (Vicia faba) are available in a variety of colours and have been found to contain appreciable amounts of phenolic compounds (Okada & Okada, 2007; Amarowicz et al., 1996). These amounts vary between different faba bean genotypes (Siah et al., 2008); however, the extent of this variation in Australia-grown faba bean genotypes and their link to possible health effects is not well understood. In this study, the colour intensities, phenolic contents and antioxidant activities of 12 different Australian grown faba bean genotypes were measured. On-line High Performance Liquird Chromatography (HPLC) analyses of the antioxidant activity of individual phenolic compounds were also carried out.