CHICAGO, Jan. 20 (Xinhua) -- A study suggests that some species of gut bacteria break down the fiber in such a way that it not only becomes digestible, but releases ferulic acid, an important antioxidant with multiple health benefits
The researchers at the University of Illinois (UI), the University of Michigan (UM) and Mie University in Japan studied the genomes and digestive activity of bacteria in the intestine, and found that a group of Bacteroides bacteria have several enzymes that break down arabinoxylans, some of which had not been seen or catalogued before. One enzyme the group discovered is so active that it cuts off any ferulic acid it comes across, releasing large amounts of the antioxidant.
"These bacteria can sense the difference between simple and complex arabinoxylans to deploy a large set of enzymes that function like scissors to cut the linkages in complex arabinoxylans into their unit sugars, and at the same time release the ferulic acid," said study leader Isaac Cann, a professor of animal sciences and microbiology at UI.
Importantly, none of the bacteria the group studied used the ferulic acid after releasing it, thus making it available for absorption in the human gut.
Understanding this mechanism of how bacteria in the colon help the body break down dietary fiber and access ferulic acid has applications for personalized nutrition. With the compound's protective activity against certain diseases and its role in modulating inflammation and immune response, patients may benefit from probiotic ingestion of the ferulic acid-releasing bacteria or from consuming a diet rich in arabinoxylan fiber, Cann said.
"This is one example of how the microbiome impacts human health and nutrition," Cann said.
The findings, posted on UI's website on Tuesday, have been published in the journal Nature Communications. Enditem