Orange, Tangerine Peel Compound May Lower Cholesterol

LONDON, Ontario--A compound found in the peels of oranges and tangerines-- polymethoxylated flavones (PMFs)--may lower cholesterol, according to a study published in the May 12 issue of the Journal of Agricultural and Food Chemistry (52, 10:2879-56, 2004) (pubs.acs.org/journals/jafcau); it is the first study to demonstrate PMFs can lower cholesterol, according to the researchers.

Hamsters with diet-induced hypercholesterolemia were fed a normal chow diet for one week and then divided into four treatment groups, where they were fed an experimental diet for 35 days. All diets contained 25 percent casein, with or without supplements of Tan (one of the most common PMFs), a standardized Tan/Nob mixture (Nob is also a common PMF), a commercial extract containing PMFs from tangerines, or a combination of Hesp and Nar (two glycosides of the citrus flavanones hesperetin from oranges and naringenin from grapefruit). According to the study, a diet containing 1 percent PMFs (Tan, Tan/Nob or PMF) can significantly reduce LDL (bad) cholesterol by 32 percent to 40 percent. Flavonoid supplementation had no effect on body weight, HDL (good) cholesterol or food consumption, however. Our study has shown that PMFs have the most potent cholesterol-lowering effect of any other citrus flavonoid, said Elzbieta Kurowska, Ph.D., lead investigator of the study and vice president of research at London, Ontario-based KGK Synergize Inc. The company offers a cholesterol-lowering ingredient, Sytrinol, that contains PMFs and vitamin E, which, according to Kurowska, seems to enhance the compounds effect; Sytrinol is exclusively distributed by Chicago's SourceOne Global.

The study was funded by KGK Synergize and USDAs (U.S. Department of Agriculture) Citrus and Subtropical Products Laboratory.