Powerful pink microalgae: COSSMA

Since customers like to use products that are easy to use but have a variety of effects, the market for multifunctional active ingredients is growing more and more. Protection and care are also increasingly in demand when it comes to sun protection. Latest research results show that Dunaliella salina has special properties for this topic.

As our lives increasingly shift outdoors, the demand for global sun care solutions has expanded to include multi-protective benefits and multifunctional claims. According to Mintel, more sun care brands are blurring with skincare to appeal to consumers, especially those who have been even more engaged with skincare during the pandemic. Concerns surrounding blue light, pollution, and glycation have grown, and consumers want more than just sun protection from their sun care products.

Innovating by adding value to familiar products is the primary way for brands to combine sun care with skincare, in promoting widely beneficial protection alongside well-being trends. The evolution of sun care will help the category penetrate broader and more diverse consumer groups, and additional protective claims will improve product differentiation on the market.

As the beauty industry trends toward greener formulation, innovative sun care will balance clean ingredients with the need for sun protection efficacy. Furthermore, consumers are increasingly concerned about the environmental impact of the products they use, and they want more action from brands on sustainability.

With safety and sustainability as key priorities, consumers will increasingly seek formulas that are good for their health and for the planet.

figure 1: Ex-vivo evaluation of anti-glycation activity. A. Illustrative images of skin explants cross-sections immunoassayed for CML B. Quantification of the CML expression. figures: Lucas Meyer Cosmetics

Glycation and skin ageing

Solar radiation, especially UV radiation plays a key role in the formation and deposition of advanced glycated end products (AGEs) in the skin.

Glycation is a slow chemical reaction where reducing sugars are added to proteins, causing irreversible damage to their structure and function. It modifies the biomechanical and functional properties of key structural proteins of the skin, interfering with numerous physiological functions. Through interaction with their receptor for advanced glycation end products (Rage), AGEs activate molecular pathways in many skin cell types disturbing the tissue homeostasis and accelerating the skin ageing in process. Glycation results in loss of skin elasticity, coarsely wrinkled skin, inflamed skin, and uneven skin tone.

figure 2: Avea 3D evaluation of skin roughness. A. Illustrative images of the malar area. B. Quantification of skin roughness. figures: Lucas Meyer Cosmetics

Strategies to fight results of glycation

There are several strategies cosmetic formulators can use to fight that process1. The first and the most common is inhibiting the formation of AGEs. Since oxidation is a crucial step in the irreversible changes to the glycated proteins, formulators often use strong antioxidants, mostly plant-derived polyphenols.

Second, one can attempt removing AGEs already formed by degrading glycated proteins – a strategy highly desired by formulators but not easily achieved.

Last, reducing the AGE-mediated signalling cascade for example by downregulating the expression of the receptor for AGE (Rage). Multifunctional actives that can do all the above are rare and should be a novel and effective solution.

figure 3: Avea 3D evaluation of anti-wrinkle effect. A. Illustrative processed Avea 3D images of crow’s feet wrinkles (red represent wrinkle). B. Quantification of wrinkle count. figures: Lucas Meyer Cosmetics

Algae extracts

Algae extracts have been shown to hold strong anti-glycation potential. The ability of microalgal extracts to inhibit AGE formation is different from that of many terrestrial plants. In microalgae, a wide range of non-phenolic antioxidants can be produced like polyunsaturated fatty acids and carotenoids. The use of coloured carotenoids, however, presents a challenge to cosmetic formulators as they would strongly colour the formula and potentially the skin.

The colourless carotenoids, phytoene, and phytofluene are the precursors to all coloured carotenoids. They hold a great promise to cosmetic formulators as they bring all the benefits of carotenoids including antioxidative, DNA protection, anti-inflammatory, and potentially anti-glycation without the distinctive colour. Therefore, a new developed purified, oil-soluble extract of pink microalgae² calibrated for its colourless carotenoids and polyunsaturated fatty acids content and uniquely designed to fight the ageing caused by glycation.

Dunaliella salina (the pink microalgae) is a halophile green microalga found in sea salt fields. Under stress, high solar radiation, these normally green algae adapt by generating large amounts of beta-carotene which  gives it the characteristic orangepinkish colour. Interestingly, the algae also produce large amounts of beta-carotene precursors phytoene and phytofluene along with unique fatty acids. This presents an opportunity for the commercial biological production of these substances.

Observing the natural ability of Dunaliella salina to withstand harsh solar irradiation conditions inspired the researchers to capture nature’s photoprotective mechanisms and to bio-mimic its adaptive power.

Lab-grown beauty solution

A circular economy approach was adopted for Dunaliella cultivation by integrating it into farms with existing facilities to produce salt products, to minimise the environmental impact of energy and material use. By-products like heat, and CO2 emissions (otherwise released to the environment) from nearby factories were used to keep the algae in optimal conditions and leave a positive impact on the planet.

The colourless carotenoids and polyunsaturated fatty acids are preferentially extracted using the solvent-free supercritical CO2 extraction method. This keeps the algae nutrients as close as possible to the way they appear in nature, enhancing their bioavailability and maximising their efficacy. The carotenoid-rich extract is then purified by removal of residual beta-carotene, dissolved in jojoba oil as a carrier oil, and standardised for colourless carotenoid content. The solution is designed to be easily biodegradable and aquatic ecosystem friendly.

Inhibiting and detoxifying AGE

To test the efficacy of the solution as optimal anti-glycative active the glycation was induced in skin explants, then the expression of carboxymethyl lysine (CML) was measured, the most common AGE in the skin. As expected, glycation induction resulted in a strong significant increase in CML expression vs. baseline. However, treatment with 0.5% of the active ingredient significantly reduced CML expression. Interestingly, it decreased CML expression below baseline levels both in challenged and unchallenged conditions. These results indicate that the active not only efficiently prevents the formation of AGEs but also efficiently detoxifies existing ones (figure 1).

Researchers also found that the solution upregulates the expression of NRF2, a transcription factor known to upregulate the expression of antioxidant and AGE detoxifying enzymes, thus improving the cellular capacity to prevent the formation of AGEs and detoxify pre-existing ones. Moreover, they found that it down-regulates the expression of the receptor for AGE (Rage), thus inhibiting the AGE-mediated signalling.

Fighting solar ageing

Next, the ability of the active was tested to counter the effects of intense and prolonged solar exposure. To this end, a panel of 25 women (multi-ethnic skin types) was selected based on expected daily intense solar exposure over the course of the 56-day study (beachgoing or similar activities), which was carried out in southern Europe during the peak summer months. Volunteers were instructed to keep their regular sun-blocker routine throughout the study.

A simple gel cream containing 1% of the active ingredient vs. placebo, in which the active ingredient was replaced with jojoba oil, was applied on a split body (face and forearms) twice a day. Measurements were done on D0, D28, and D56.

AGE reader measurements showed a significant decrease in AGE score vs. placebo and vs. D0 already after 28 days of use. Indicating that the active not only prevents the formation of solar-induced AGEs but also efficiently detoxifies pre-existing ones in-vivo.

As expected from the efficient anti-glycation active ingredient, cutometer analysis, and clinician grading revealed significant improvement to skin firmness (+7%) and elasticity (+14%) in most of the volunteers tested (>92%).

It is worth noting that in many clinical parameters (roughness, wrinkles, red spots, and UV spots) at both time points, a worsening over time is observed with the placebo product (although keeping regular sun blocker routine), which is consistent with the high solar exposure conditions of the study. The Dunaliella solution not only negates these effects but reverses them, producing significant improvements vs. the initial state at D0.

Aeva 3D data showed a significant improvement in the skin roughness index (-10%) (figure 2). It also demonstrated a significant decrease in wrinkle count (-32%) (figure 3). Visia imaging analysis revealed a significant decrease in red spots and UV spots occurrence (-26% and -7% respectively). In correlation with UV spots observation, clinician grading showed significant improvement to skin evenness score (+17%) in 96% of the volunteers. Clinical scores noted above refer to change vs. placebo at D56.□Q