Orange peels, often discarded as waste, might hold a vital key to enhancing cardiovascular health, according to new research led by the University of Florida. The groundbreaking findings have been published in the Journal of Agricultural and Food Chemistry.
Heart disease remains the leading cause of death among men, women, and people across most racial and ethnic groups, as highlighted by the Centers for Disease Control and Prevention (CDC). Recent studies have revealed that certain gut bacteria contribute to the development of cardiovascular disease. These bacteria produce a compound called trimethylamine N-oxide (TMAO) when they metabolize specific nutrients during digestion. Elevated TMAO levels are linked to a higher risk of cardiovascular disease, as demonstrated by researchers at the Cleveland Clinic.
Yu Wang, an associate professor of food science and human nutrition at the University of Florida's Institute of Food and Agricultural Sciences (UF/IFAS), spearheaded a study to explore the potential of orange peel extracts in reducing TMAO and its precursor, trimethylamine (TMA). Her team tested two types of extracts from orange peels: a polar fraction and a non-polar fraction.
Wang explained that the extraction process involved using solvents of different polarities to separate the compounds. “If you imagine your salad dressing, anything in the water or vinegar part is the polar fraction; anything in the oil, away from water, is the non-polar fraction,” Wang illustrated. “The solvents we used were not exactly like water and oil, but they possess similar polarity.”
The study's results were promising. The non-polar fraction of the orange peel extract effectively inhibited the production of harmful TMAO. Additionally, the polar fraction contained a compound called feruloylputrescine, which significantly inhibited the enzyme responsible for TMA production.
“This is a novel finding that highlights the previously unrecognized health potential of feruloylputrescine in reducing the risk of cardiovascular disease,” Wang said.
The implications of these findings are significant, considering that approximately 5 million tons of orange peels are generated annually by the orange juice industry in the United States, with nearly 95% of Florida oranges being processed for juice. While a portion of these peels is used as cattle feed, much of it is wasted. However, the Food and Drug Administration (FDA) deems natural orange peel extracts safe for human consumption, which opens the door to more beneficial uses.
“These findings suggest that orange peels, often discarded as waste in the citrus industry, can be repurposed into valuable health-promoting ingredients, such as dietary supplements or food ingredients,” Wang said, noting her position at the UF/IFAS Citrus Research and Education Center.
“Our research paves the way for developing functional foods enriched with these bioactive compounds, providing new therapeutic strategies for heart health.”
The potential to transform a common waste product into a powerful health tool offers a promising avenue for both the citrus industry and public health. As research progresses, orange peels may soon be recognized not just for their contribution to citrus flavor, but as an integral component in the fight against cardiovascular disease.
Source: University of Florida