Characterization of a Hot Water Extract of an Edible Cyanobacterium Nostochopsis sp. for Use as an Ingredient in Cosmetics

Cyanobacteria contain substances of high biological value and are used to meet the high demands of the global food and pharmaceutical industries. In this study, we prepared a hot water extract of the edible cyanobacterium, Nostochopsis, and evaluated its possible use as an ingredient in cosmetics. Specifically, a hot water extract of Nostochopsis was assayed for tyrosinase inhibitory activity. Tyrosinase, a key enzyme in skin melanin synthesis, was strongly inhibited by the Nostochopsis hot water extract, which reduced α-melanocyte-stimulating hormoneinduced melanin synthesis in B16 mouse melanoma cells. Thus, Nostochopsis hot water extract may be suitable as an ingredient in cosmetics.