People living in Asian countries such as Korea, China and Japan commonly consume edible marine algae such as seaweed in their diet. These microalgae or microscopic plants are known to produce different types of beneficial proteins that form nearly 47 percent of the dried formulations, such as seaweed used for sushi. These proteins might help in lowering blood pressure. This review looked at studies and evidence that showed health benefits to the heart from consuming these microalgae and macroalgae preparations.
The number of patients affected by heart disease is increasing annually, with at least one in three Americans having some form of heart disease. Of these, a large majority suffers from high blood pressure that needs to be controlled using medication. Reducing high blood pressure helps lower heart disease risk and death due to heart disease. Apart from conventional pharmaceutical agents, researchers are on the lookout for natural dietary and food supplements that can reduce blood pressure. Some food-derived nutrients are “bioactive nutrients”, present in food products or released by the human gut by fermentation, when it takes in certain foods. Sea organisms such as microalgae or seaweeds (macroalgae) produce certain beneficial or protective nutrients to cope with extreme climate, salinity and other adversities within their natural habitat. People of Korea, China and Japan are known to include these algae in their regular diet. Seaweeds are a rich source of fibers, proteins, minerals and polysaccharides. This review attempted to look at studies showing the beneficial effects of these microalgal proteins on humans to attempt to identify their potential as preventive nutritional supplements.
* The review of previous studies on bioactive peptides from seaweeds and microalgae showed that commonly edible macroalgae are brown, green and red. These macroalgae are rich sources of vitamins A, D, E, some B vitamins and vitamin C. They are also rich sources of minerals such as sodium, phosphorus, calcium, potassium and some polysaccharides.
* Some studies have shown that regular intake of these macroalgae can provide protection from diseases such as breast cancer and reduce the risk of diabetes.
* Some of these bioactive peptides, available as nutritional drinks, are also known to inhibit an enzyme called “angiotensin converting enzyme.” By this method, these peptides can reduce blood pressure, since a major class of blood pressure-reducing drugs act by this mechanism.
* These microalgae and macroalgae also contain PUFA or polyunsaturated fatty acids. Intake of polyunsaturated fatty acids in the diet is said to reduce blood pressure, blood cholesterol, and inflammation-related changes and improve heart health.
Authors write that most of the studies till date have looked at the inhibition of the angiotensin converting enzyme in their attempt to explain blood pressure reduction. They suggest further studies that look at other methods by which these peptides present in algae can reduce blood pressure as well. Most of these peptides may be destroyed in the high temperatures of cooking. Methods and studies are required to improve heat-stability of these peptides.
This review shows that the eastern Asian population that takes in more of protein-rich microalgae and macroalgae benefits from this diet to a large extent. While some properties that protect the heart by way of reduction of blood pressure, protection against diabetes, and high blood cholesterol appear in some of the studies, there is paucity of studies that examine the complex methods by which these microalgae can maintain heart health. Authors suggest deeper study of the mechanism of lowering of blood pressure by these peptides. They add that heat due to cooking may destroy these peptides; methods such as microencapsulation and protection of these peptides from heat are necessary. These studies could pave the way for nutritional supplementation using microalgae and macroalgae becoming important methods for prevention of heart disease.
For More Information:
Heart Health Peptides from Macroalgae and Their Potential Use in Functional Foods
Publication Journal: Journal of Agricultural and Food Chemistry, May 2011
By Ciaran Fitzgerald; Eimear Gallagher; University of London, England and Teagasc Food Research Centre, Dublin, Ireland