Elizabeth Jeffery, Michael Miller and Ren-Hau Lai of the University of Illinois say they found sulforaphane -- the cancer-fighting agent in broccoli -- can be released from its parent compound glucoraphanin by bacteria in the lower gut and absorbed into the body.
"This discovery raises the possibility that we will be able to enhance the activity of these bacteria in the colon, increasing broccoli's cancer-preventive power," the researchers say in a statement.
The researchers proved it by injecting glucoraphanin into the ligated lower gut of rats and demonstrated that sulforaphane is present in blood from the mesenteric vein, which flows from the gut to the liver.
"The presence of sulforaphane in measurable amounts shows that it's being converted in the lower intestine and is available for absorption in the body," Jeffery says.
Sulforaphane is an extremely potent cancer-fighting agent, Jeffrey says.
"Less than one daily serving of broccoli is enough to have an anti-cancer effect," Jeffrey says. "With many of the other bioactive foods you hear about, vast amounts are required for a measurable outcome."
The findings are scheduled to be published in the November issue of the journal Food & Function.