Due to climate change and its associated factors, there has been an increased influx of pelagic brown algae biomass drifting freely in the Caribbean Sea in recent years. Its use as an industrial recyclable material is feasible, although pelagic Sargassum species have Arsenic (As) heavy metal content; among 531 tested pesticide residues applied to vegetables, fruit, infant food, herbs, and spices, zero were found in Sargassum. Sargassum also contains sulfated polysaccharides and oligosaccharides, which are known to be beneficial immunomodulators. Our results thus suggest Sargassum to be a functionally useful organic material in small quantities as an additive in animal feed. With improved chemical extraction methods, it could also be highly effective in adjusted proportions in cosmetics and for other industrial uses. A viable solution for predicting and tracking the large-scale movements of algal masses is provided. Furthermore, a method for addressing increasing Sargassum influx is proposed via its use as an industrial recyclable material following composition analysis, evaluation and safety assessments for cosmetic use, and research and design of new beauty products and other functional cosmetics.

Non-geniculate crustose coralline algae (NCA) are important in algal reef ecosystems, yet their physiological responses to turbidity and sediment burial remain insufficiently understood. We examined how six turbidity levels (0–300 mg L⁻¹) and four sediment deposition depths (0–3 cm) affected two dominant species, Sporolithon sp. and Phymatolithon sp. Under turbidity treatments, for Sporolithon sp., Fv/Fm was lowest at 0 mg L⁻¹ (0.43 ± 0.01) and highest at 250 mg L⁻¹ (0.62 ± 0.01). ETRmax increased markedly under 150 mg L⁻¹ (17.94 ± 0.27) but declined under 300 mg L⁻¹ (5.33 ± 0.19). In Phymatolithon sp., turbidity levels of 150–250 mg L⁻¹ produced consistently higher Fv/Fm values (0.58–0.60) and the lowest ETRmax occurred at 300 mg L⁻¹ (5.71 ± 0.34). Sediment burial caused strong early reductions in photosynthetic performance. In Sporolithon sp., all burial depths except 0 cm caused significant Fv/Fm declines within five days (decrease to 0.46). After 45 days, ETRmax ranged from 9.28 ± 0.38 at 0 cm to 4.02 ± 0.11 at 3 cm, with intermediate values at 1 and 2 cm. Phymatolithon sp. showed rapid declines in Fv/Fm at all depths (1 to 3 cm) before partial recovery after 15–20 days. Overall, moderate turbidity (150–250 mg L⁻¹) provided protective light attenuation, whereas sediment deposition imposed strong early physiological stress. The contrasting responses of the two species highlight different adaptive strategies for surviving low-light and sediment-rich environments.

Sargassum horneri is a highly productive macroalgal species capable of assimilating dissolved inorganic carbon (DIC) and converting CO₂ into carbohydrates, making it a promising solution for carbon capture and biomass enhancement. Owing to its wide distribution and natural abundance, the utilization of S. horneri may help mitigate rising oceanic CO₂ concentrations. This study evaluated the combined effects of inorganic carbon availability (2000, 4000, and 8000 μM NaHCO₃) and irradiance (100, 150, and 200 µmol photons m⁻² s⁻¹) on photosynthetic performance and growth across short-term (24 h) and long-term (4-week) experimental trials. Carbon enrichment and light intensity interacted to significantly influence growth and carbon assimilation. The highest growth rate (35.83 ± 3.95%) was observed under 8000 μM DIC (0.75 g L⁻¹) at 200 µmol photons m⁻² s⁻¹, corresponding to an optimal mean growth condition of 19 ± 0.04% (p < 0.05). These findings demonstrate that elevated inorganic carbon enhances photosynthetic efficiency by supplying sufficient substrate for carbon fixation, thereby supporting the feasibility of Sargassum horneri as a viable species for CO₂ absorption and carbon capture applications.