Anti-aging effect of <i>Grateloupia elata</i> extract in skin

Grateloupia elata (G.elata) is a red alga of the Rhodophyta and it grows along the southern and eastern coastlines, and Jeju Island in South Korea.Since the biological effects of G. elata have not been reported, this study was designed to investigate its antioxidant and anti-aging effects.For this purpose, the extract of G. elata was prepared using 100% ethanol.First, G. elata extract (1000, 5000 g/mL) showed antioxidant activity by scavenging 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammoniumsalt radical by 0.82-and 0.49-fold, 2,2-diphenyl-2-picrylhydrazyl radical by 0.78and 0.39-fold.In addition, the contents of polyphenols and flavonoids which are well known as antioxidants, in G. elata extract were 29.2080.396mgGAE/g and 29.1341.234mgQE/g, respectively.Next, activity of G. elata extract in inhibition of collagenase and elastase activity was evaluated.The result showed that G. elata extract (10 mg/mL) inhibited the activity of collagenase and elastase by 57.87 and 38.46%, respectively.Further, G. elata extract (100, 1000 g/mL) increased the contents of procollagen released in the culture of fibroblasts by 1.69-and 2.45-fold, respectively and its effect was greater than that of ascorbic acid (1.23-fold).Finally, the secretion of matrix metalloproteinases-1 (MMP-1) was reduced by ascorbic acid to 0.59-fold while G. elata extract reduced it to 0.86-and 0.54-fold, respectively and the level of MMP-1 mRNA expression decreased by ascorbic acid to 0.63-fold while G. elata extract decreased it to 0.87-and 0.56-fold, respectively.Taken together, antioxidant and anti-wrinkle effects of G. elata suggest that it could be a new potential material for functional cosmetics of antiaging.