In the future, scientists could use the enzyme activity to gauge a broccoli variety's anti-cancer potential. Data from several previously published studies have shown that people who eat cruciferous vegetables like broccoli have a lower incidence of colon and rectal cancers. Occurring in two out of 1,000 people, these account for 15 percent of all cancer deaths. Broccoli florets and young seedlings are rich sources of glucoraphanin and its breakdown product, sulforaphane. Sulforaphane is a potent inducer of mammalian detoxification enzyme activity and inhibits early tumor growth in rodent models.
Scientists know little about variations of glucoraphanin and sulforaphane in broccoli varieties.
If genetic variation among varieties does exist, then breeders could exploit it to develop new varieties with greater levels of the protective compounds. And eating such improved broccoli might stimulate an enhanced chemoprotective response against cancer. ARS is the chief scientific research agency of the U.S. Department of Agriculture.