Investigating the potential of Ulva rigida extracts as a natural anti-aging agent in cosmetics

Based on the study, extracts from sea lettuce (Ulva rigida) or UR show significant promise as a natural anti-aging ingredient for skincare products. The research, conducted on specimens from Phetchaburi, Thailand, compared three extraction methods: juice squeezing (J), boiling (B), and maceration (M) by using 95% ethanol. The results demonstrated that these extracts contain beneficial compounds like phenolics and flavonoids, including rutin, catechin, and quercetin, which contribute to their biological properties. Furthermore, all extracts (UR-J, UR-B, and UR-M) exhibited powerful anti-aging effects. Specifically, the UR-M extracts effectively inhibited anti-melanogenesis activity (5.88 ± 1.25%) and the tyrosinase activity (IC₅₀ of 1.38 ± 0.68 mg/ml), and also promoted collagen biosynthesis (37.68 ± 2.24%). All UR extract was particularly notable for its ability to stimulate key anti-aging gene, SIRT1, which is superior to resveratrol (87.8 ± 1.8%). Importantly, none of the extracts showed cytotoxicity at a concentration of 1.0 mg/mL, confirming their safety for use on human skin. These findings suggest that the sea lettuce (UR) extracts are a strong candidate for future development as an anti-aging agent in the cosmetic industry.