Anti-glycation properties of the aqueous extract solutions of dried algae products harvested and made in the Miura Peninsula, Japan, and effect of lactic acid fermentation on the properties

Abstract

To clarify the anti-oxidant and anti-glycation properties of traditional edible algae, aqueous extract solutions (AESs) from eight dried algal products that were commercially available in the Miura Peninsula of Japan were prepared. AESs of the red alga, Pyropia sp. (nori), demonstrated strong Fe-reducing power with a high total phenolic compound content. On the other hand, the sporophyll of the brown alga Undaria pinnatifida (mekabu) exhibited high superoxide anion radical-scavenging capacity. Anti-glycation activity in bovine serum albumin (BSA)-fructose (Fru) and in BSA-methylglyoxal (MGO) was high for nori and the stem of Sargassum fusiforme (naga-hijiki). The results of the BSA-MGO model agreed with those of the phenolic content and Fe-reducing power. Anti-glycation activities of mekabu, Sargassum horneri (akamoku), naga-hijiki, the frond of U. pinnatifida (wakame), and Gelidium elegans (tengusa) in the BSA-Fru model were clearly increased by fermentation with Lactobacillus plantarum Miura-SU1 isolated from the Miura Peninsula. The results of the present study suggest that, once fermented with lactic acid bacteria (LAB), akamoku and other edible algae will have a potential role in preventing diabetes- and aging-related glycation.