Obesity is a complex health condition characterized by excessive adipose tissue accumulation, leading to significant metabolic disturbances such as insulin resistance and cardiovascular diseases. Fatty acid synthase (FAS), a key enzyme in lipogenesis, has been identified as a potential therapeutic target for obesity due to its role in adipocyte differentiation and lipid accumulation. This study employed a multidisciplinary approach involving in silico and in vitro analyses to investigate the anti-adipogenic properties of maclurin, a natural phenolic compound derived from Morus alba. Using SwissDock software (ChEMBL version 23), we predicted protein interactions and demonstrated a high probability (95.6%) of maclurin targeting FAS, surpassing the interaction rates of established inhibitors like cerulenin. Docking simulations revealed maclurin’s superior binding affinity to FAS, with a binding score of −7.3 kcal/mol compared to −6.7 kcal/mol for cerulenin. Subsequent in vitro assays confirmed these findings, with maclurin effectively inhibiting FAS activity in a concentration-dependent manner in 3T3-L1 adipocytes, without compromising cell viability. Furthermore, maclurin treatment resulted in significant reductions in lipid accumulation and the downregulated expression of critical adipogenic genes such as PPARγ, C/EBPα, and FAS, indicating the suppression of adipocyte differentiation. Maclurin shows potential as a novel FAS inhibitor with significant anti-adipogenic effects, offering a promising therapeutic avenue for the treatment and prevention of obesity.

Sargassum serratifolium (S. serratifolium), listed in the Food Code, is known for its antioxidant and anti-inflammatory properties and is used in cosmetic applications. However, due to limited industrial utilization and overaccumulation in marine environments, Sargassum has been designated as a marine pollutant by the UN Environment Agency. To improve resource efficiency and reduce environmental burden, this study developed a dual-extraction strategy to isolate extracellular vesicles (EVs) and extract ethanol-soluble substances from the same S. serratifolium biomass. The extracellular vesicles derived from S. serratifolium (SEVs) were isolated and characterized based on their particle size, morphology, concentration, and cargo molecules, including mRNA and proteins. Their antioxidant and anti-inflammatory activities were evaluated using cellular assays, while their effects on melanogenesis and melanosome transport were assessed in B16F10 melanoma cells. Transcriptomic analysis by RNA sequencing was further performed to investigate the molecular pathways involved in SEV-mediated regulation of melanosome transport. SEVs isolation did not affect the yield or biological activity of the S. serratifolium ethanol-soluble fraction. Based on our previous finding that the ethanol extract of S. serratifolium (ESS) suppresses melanin synthesis, the present study focused on investigating the effects and mechanisms of SEVs on melanogenesis and melanosome transport. SEVs were nanoscale vesicles containing mRNA and proteins and showed antioxidant and anti-inflammatory effects in cellular assays. Although SEVs did not reduce melanin production in B16F10 cells, they significantly inhibited melanosome transport. RNA sequencing suggested that SEVs regulated melanosome transport through pathways related to the extracellular matrix, actin filament organization, and calcium ion homeostasis. These findings suggest that SEVs exert anti-melanogenic effects by targeting melanosome transport, providing a complementary mechanism to the previously reported inhibition of melanin synthesis by ESS. These findings demonstrate a sustainable strategy for producing functional EVs and bioactive extracts from a single S. serratifolium biomass source and support their potential use in cosmetic or therapeutic applications targeting hyperpigmentation.