Heart health peptides from macroalgae and their potential use in functional foods

22 Jun 2011

Ciaran Fiztgerald

There are over 500 different species of macroalgae native to Irish shores. Traditionally, carrageenan moss (Chondrus crispus) and laver (Porphyra sp.) were eaten in breads, however, the extent of their use as a resource for bioactive molecules has not been exploited to date.

Whilst macroalgae are a common staple in the diets of Asian countries such as China, Korea and Japan, traditional western diets rarely include macroalgae. Valuable health benefits beyond basic nutrition are already associated with the consumption of whole macroalgae. For example, an inverse relationship between daily consumption of certain species and the occurrence of breast cancer and diabetes mellitus has been suggested (Kadam & Prabhasankar, 2010).

As a result of their harsh environment, macroalgae produce unique biomolecules and secondary metabolites that often differ from those found in terrestrial plants. The protein content of macroalgae can be 47% of the dry weight and is dependant on the species and time of harvesting of the plant. Bioactive peptides were released previously from the macroalgal proteins of wakame (Undaria pinnatifida) using enzyme hydrolysis and had angiotensin I converting enzyme (ACE-I) inhibitory activity. This enzyme is important in the control of high blood pressure or hypertension, a serious risk factor in cardiovascular disease (CVD).

A research group at Teagasc Ashtown are currently looking at risk factors for CVD, that could be reduced through the use and inclusion of macroalgal proteins and peptides in foods, specifically bread. Bread is a ubiquitous food, consumed worldwide, and could serve as an excellent carrier of functional ingredients such as bioactive peptides. For example, antithrombotic peptides, renin inhibitory peptides, and platelet activating factor acetylhydrolase (PAF-AH) inhibitory pepetides may all play a role in the prevention of high blood pressure.

Indeed, ACE-I inhibitory peptides are already used in food products. Beverages such as Ameal-S ® and Evolus ® use ACE-I inhibitory bioactive peptides sourced from fermented milk protein and have proven antihypertensive effects. Marine peptides are also used in soup products in Japan for their antihypertensive benefits. Macroalgae are an untapped source of heart health bioactive peptides that have yet to be fully exploited for inclusion as ingredients in the functional foods market.

For further details on this subject:

Fitzgerald C, Gallagher E, Tasdemir D, Hayes M (2011) Heart health peptides from macroalgae and their potential use in functional foods. J. Agric. Food Chem.

Aneiros A, Garateix A (2004) Bioactive peptides from marine sources: pharmacological properties and isolation procedures. J. Chromatogr.

Kadam SU, Prabhasankar P (2010) Marine foods as functional ingredients in bakery and pasta products. Food Res. Int.