MAAs produced by seaweed found to suppress rise in blood pressure — Meijo University research attracts attention: Beyond skincare, into health foods

A research group led by Professor Hakuto Kageyama of the Graduate School of Environmental and Human Sciences, Meijo University, has found that "mycosporine-like amino acids (MAAs)"—UV-absorbing compounds produced by seaweed and cyanobacteria—inhibit ACE (angiotensin-converting enzyme), an enzyme involved in raising blood pressure. Their findings are expected to expand the application of MAAs beyond cosmetics into the food and health sectors. The results were published on January 19 in Bioscience, Biotechnology, and Biochemistry, a journal published by the Japan Society for Bioscience, Biotechnology, and Agrochemistry.

MAAs are found in abundance in susabi-nori (Pyropia yezoensis), which accounts for the vast majority of edible nori consumed in Japan. They are known as natural compounds that protect cells from UV radiation and have attracted attention from a skincare perspective for their antioxidant and anti-inflammatory properties. Although susabi-nori is eaten on a daily basis, its health effects inside the body had not been adequately studied.

In this study, two types of MAAs were used for functional evaluation: "porphyra-334," a typical MAA found in abundance in susabi-nori, and "GlcHMS326," an atypical MAA produced by cyanobacteria inhabiting a hot spring environment in Thailand. GlcHMS326 has an unusual structure that has undergone multiple chemical modifications, including glycosylation, methylation, and hydroxylation.

In addition to antioxidant, antiglycation, and collagenase inhibitory activities, the effects on ACE (angiotensin-converting enzyme), an enzyme involved in blood-pressure regulation, were also examined. ACE is a key enzyme in the reaction that raises blood pressure; inhibiting it suppresses that rise.

The evaluation showed that both MAAs have ACE-inhibitory activity. In terms of ACE inhibition and antiglycation, porphyra-334 showed stronger activity. The findings demonstrate that nori, an everyday food, contains functionally beneficial health compounds.

GlcHMS326 showed stronger effects in terms of antioxidant and collagenase inhibitory activities.

These results demonstrate that the functional properties of MAAs differ depending on their chemical structure, providing an important foundation for expanding applied research.

Kageyama commented: "Mycosporine-like amino acids (MAAs) have attracted attention as a 'topical ingredient' for UV protection and anti-aging skincare. By confirming their ability to suppress a rise in blood pressure, we have been able to show that MAAs not only protect the skin but also have the potential to promote health from within the body when taken orally. We believe this represents a step toward expanding the application of MAAs from external use to functional ingredients."

Journal Information
Publication: Bioscience, Biotechnology, and Biochemistry
Title: Comparative functional evaluation of the atypically modified GlcHMS326 and porphyra-334, Two structurally distinct mycosporine-like amino acids
DOI: 10.1093/bbb/zbag011