U. S. researchers said curcumin, turmeric's main ingredient, has a wide repertoire of health benefits ranging from antioxidant, anti-cancer, antibiotic, antiviral and other properties.

India has long known the healing powers of turmeric and the spice has been used for centuries to treat wounds, infections and other health problems though how exactly it works inside the body was never clear.

U. S. researchers said that curcumin works by inserting itself into cell membranes and makes them more orderly and resistant to infection. University of Michigan researchers led by Ayyalusamy Ramamoorthy, a professor of chemistry and biophysics, reported that curcumin makes cell membranes more orderly and that improves the cells resistance to infection and malignancy.

Ramamoorthy said, "The membrane goes from being crazy and floppy to being more disciplined and ordered, so that information flow through it can be controlled."

In the study Ramamoorthy a technique called solid-state NMR spectroscopy to reveal atom-level details of these important molecules. He added that the two-dimensional solid-state nuclear magnetic resonance technique used to probe curcumin-membrane communication in this study was developed by the research group.

In the findings published online March 3 in the Journal of the American Chemical Society, Ramamoorthy said, "Probing high-resolution intermolecular interactions in the messy membrane environment has been a major challenge to commonly-used biophysical techniques."

Earlier scientists had speculated that curcumin works by interacting directly with membrane proteins, a speculation that this research has challenged. The researchers found that curcumin regulates the action of membrane proteins indirectly, by changing the physical properties of the membrane.

Ramamoorthy's group is now working in collaboration with chemistry professor Masato Koreeda and U-M Life Sciences Institute researcher Jason Gestwicki to study a variety of curcumin derivatives, some of which have enhanced potency. "We want to see how these various derivatives interact with the membrane, to see if the interactions are the same as what we have observed in the current study," Ramamoorthy said. "Such a comparative study could lead to the development of potent compounds to treat infection and other diseases."

Using similar methods Ramamoorthy's team is investigating the effects of curcumin on the formation of amyloids, clumps of fibrous protein believed to be involved in type 2 diabetes, Alzheimer's disease, Parkinson's disease, and many other diseases.

They are also studying other natural products such as polyphenols, which are compounds found in many plant foods that are known to have antioxidant properties, and capsaicin, which is a pain reliever derived from hot peppers, to see whether they interact with membranes in the same way as curcumin does.