Comparative Efficacy of Extracts in Scar Inhibition and Skin Regeneration: A Study on UV Protection, Collagen Synthesis, and Fibroblast Proliferation.

is a red macroalga known for its bioactive compounds with antioxidant, anti-inflammatory, and skin-regenerative properties. The study aimed to examine their effects on UV protection, collagen synthesis, fibroblast proliferation, and pigmentation modulation. Bioactive compounds were extracted using two solvents, producing ethanol extract (FE) and alkaline extracts (AE). Methods involved characterizing extracts using mass spectrometry and assessing their effects on human fibroblasts under UVB-induced damage. UV absorbance, ROS production, and collagen synthesis were evaluated. The FE extract, which comprised 4-hydroxyquinoline, phytosphingosine, and docosapentaenoic acid, reinstated procollagen type I synthesis to 113% of baseline levels and reduced TGF-β1-mediated fibroblast proliferation to 87.78%. FE also suppressed and by 71% and 68%, respectively, indicating modulation of fibrosis-associated pathways. AE, containing 4-hydroxyquinoline and phenylalanine betaine, demonstrated dose-responsive cellular repair, reducing fibroblast proliferation to 97.86% and Type I expression by 73% at 1000 μg/mL. Both extracts decreased ROS production, with FE and AE reducing levels by 21.4% and 19.7%, respectively, under UVB-induced oxidative stress. FE showed superior scar inhibition, while AE excelled in skin regeneration and pigmentation management.