1. Introduction
Abundant evidence exists that consumption of tomatoes
(Solanum lycopersicum) and related food products reduces the
incidence of diseases such as chronic degenerative diseases, cardiovascular
diseases, and age-related macular degeneration in human
health (Rao & Rao, 2007). Purple tomatoes contain anthocyanins as
well as other phytochemicals (carotenoid and phenolics)
commonly found in conventional red tomatoes. A genetically
modified (GM) purple tomato was found to have additional
health-promoting effects by prolonging the life of cancer-susceptible
mice than conventional tomatoes (Gonzali, Mazzucato, &
Perata, 2009). In our previous study, a non-GM purple tomato
breeding line, V118, contained acylglycosides of petunidin and
malvidin in addition to other phytochemicals, and had stronger
antioxidant activities than some commercial red tomatoes as
measured by in vitro chemical based assays (Li et al., 2011). However,
whether or not these in vitro antioxidant activities will lead to
in vivo effects of this newly developed purple tomato is unknown.
Meanwhile, in order for a food bioactive to exert its activities, it
must be bioaccessible and bioavailable. It is also unknown whether
or not the phytochemicals, particularly the anthocyanins in the
purple tomatoes are resistant to upper gastrointestinal digestion
(bioaccessibility).