The cosmetic industry is experiencing a significant shift toward natural and sustainable products, driven by consumer demand for bioactive ingredients that offer both efficacy and safety. A primary challenge in dermatological care is maintaining optimal skin hydration and barrier function, particularly against external stressors that lead to dryness, scaling, and a sensation of tightness. To address this, researchers investigated the potential of ulvans—sulfated polysaccharides derived from green seaweeds (Ulva spp.)—due to their established antioxidant, anti-aging, and moisture-retentive properties. These were combined with mineromedicinal thermal spring waters, which are known to enhance skin barrier repair and immune defenses through their unique mineral compositions. The integration of these two elements was proposed as a solution to create a high-performance, “green” hydrating cream that leverages the additive benefits of marine biopolymers and mineral-rich waters.
Methods
Refined ulvan (purity >80% carbohydrates, >10 kDa) was extracted from Ulva spp. via hydrothermal treatment at 121 °C followed by a solvent-free ultrafiltration stage. This extract was incorporated at 1% into oil-in-water (O/W) emulsions formulated with green ingredients and As Burgas thermal spring water. A 14-day, blinded clinical study was conducted with 118 healthy volunteers who applied the creams nightly. Efficacy was assessed through objective biometry using a Corneometer® to measure skin hydration and subjective questionnaires to evaluate skin tolerance and perception.
Key Findings
- Enhanced Rheology: Creams formulated with As Burgas thermal water exhibited a more marked shear-thinning behavior, which suggests improved spreadability and applicability on the skin compared to distilled water formulations.
- Superior Hydration: The experimental group using the Ulvan+Thermal combination showed the highest objective hydration increase (median 28.0 AU), successfully shifting participants from the “dry” to the “normal/hydrated” category.
- Additive Effect: Statistical analysis confirmed an additive effect between ulvan and the sodium bicarbonate-rich thermal water, as their combined use produced significantly better results than either ingredient used alone.
- High Tolerability: All formulations were well-tolerated, showing a reduction in skin tightness; notably, scaling was significantly reduced in the ulvan-containing group, and the combination cream achieved zero irritation by the end of the study.
- Stability: The ulvan-based creams maintained physical and chemical stability, including stable pH and viscosity, for a one-year storage period.
This research highlights a novel approach in dermo-cosmetics by being the first to document the successful combination of marine ulvans with the specific mineromedicinal waters of As Burgas. The novelty lies in confirming that these renewable, natural ingredients work through complementary mechanisms to significantly boost skin hydration. Future implications of this study suggest that these formulations could be highly beneficial for individuals with reactive skin or those frequently exposed to irritants, such as healthcare workers. Furthermore, this work opens a promising research line for the therapeutic application of Galician thermal resources in the global “green” beauty market.
Link to the study: https://www.mdpi.com/1660-3397/24/8/275
