Feb. 3, 2009 - Edible mushrooms counteract the medication-altering effects of grapefruit juice, USDA researchers report.
Aside from being tasty, grapefruit juice is pretty darn good for you. It's full of antioxidants and other beneficial compounds. There's some evidence it may even help protect against cancer and heart disease.
But there's a downside to grapefruit juice. It carries a class of compounds that inhibit the liver enzymes your body needs to eliminate many widely used medications. This grapefruit/drug interaction increases the risk of drug side effects.
Recently, USDA researcher Kyung Myung, PhD, and colleagues found that an inedible fungus somehow absorbs the compounds responsible for the grapefruit/drug interaction.
Now Myung's team has found that an edible mushroom -- Morchella esculenta, better known as the yellow morel -- does the same thing. And, to a slightly lesser extent, so do other edible fungi. So far, the list includes an oyster mushroom variant, red yeast, and even the common button mushroom.
The USDA researchers macerated the mushrooms and killed them by heating them to 250 degrees Fahrenheit. Then they vacuum-filtered the mushroom mash and mixed them with either fresh grapefruit juice or grapefruit juice made from concentrate.
At the highest concentration tested -- about two-thirds of a tablespoon of yellow morel mushroom per 1.7 ounces of juice -- most of the target compounds were removed from grapefruit juice. Lesser effects were seen with the other fungi.
Separate experiments showed that mushrooms didn't remove all of the unwanted compounds from grapefruit juice. The treated juice still had more interactions with liver enzymes than orange juice. But the treated juice was only about half as active as untreated grapefruit juice.
However, Myung and colleagues did not report on how the grapefruit juice tasted after they (presumably) strained off the mushroom mash.
The findings appear in the Nov. 14, 2008, issue of the Journal of Agricultural and Food Chemistry.