Rutin emerges as a sustainable alternative in sunscreen formulations

As the cosmetics and personal care industry seeks sustainable alternatives to traditional chemical filters, the new review in the journal Cosmetics​ provides insightful findings on rutin's stability, skin permeability, and photoprotective efficacy.

Stability, permeability, and environmental benefits ​

Rutin, a natural bioflavonoid commonly found in plants such as buckwheat, apples, and citrus fruits, is renowned for its antioxidant and anti-inflammatory properties. The review investigated whether this natural compound can serve as a viable strategy for developing environmentally friendly photoprotective formulations.

The researchers emphasized that “rutin demonstrates noteworthy UV absorption capabilities, particularly in the UVB spectrum," which is responsible for causing sunburn and contributing to skin cancer risk. This property positions rutin as a promising candidate for enhancing the effectiveness of sunscreen products while reducing reliance on synthetic chemical filters that may have adverse environmental impacts.

In terms of stability, the review authors noted that “rutin maintains substantial chemical stability under various conditions," a critical factor for any sunscreen ingredient exposed to sunlight and environmental stressors. However, it was also emphasized that "the stability of rutin can be influenced by factors such as pH levels and the presence of other components within the formulation." This insight underscored the importance of meticulous formulation processes to ensure that sunscreen products containing rutin remain effective over time.

The investigation also explored rutin's skin permeability, a determinant of both efficacy and safety in topical applications. According to the scientific review, "rutin exhibits moderate skin penetration, sufficient to provide protective effects without posing significant risks of systemic absorption." This balance is essential for consumer safety, as it ensures that the active ingredient remains primarily within the skin's upper layers where UV protection is needed most.

The environmental benefits of using rutin are also highlighted in the research. Unlike some conventional chemical filters that have been linked to coral reef degradation and other ecological concerns, "rutin poses minimal environmental risks due to its natural origin and biodegradability." This aspect aligns with the growing consumer demand for products that are not only effective but also environmentally responsible.

Challenges to commercialization 

Despite these promising attributes, the researchers acknowledged several challenges in integrating rutin into commercial sunscreen products. One significant hurdle is its solubility, as "rutin's limited water solubility can complicate its incorporation into aqueous-based formulations." To address this issue, the review suggested exploring various delivery systems and formulation techniques, such as encapsulation or the use of suitable solvents, to enhance rutin's solubility and overall performance in sunscreen products.

Furthermore, the review discussed the synergistic potential of combining rutin with other natural and synthetic UV filters. The authors stated that "when paired with complementary photoprotective agents, rutin can contribute to broad-spectrum protection and improved antioxidant defense." This collaborative approach could lead to the development of more effective and balanced sunscreen formulations that meet both protective and sustainability criteria.

The next step forward 

For cosmetics and personal care product manufacturers, these findings open new avenues for innovation in the sunscreen market. Incorporating rutin into product lines could offer a competitive edge by appealing to environmentally conscious consumers and addressing regulatory pressures to replace harmful chemical filters.

The review concluded with the authors recommendation that further research and development to optimize rutin-based formulations is needed and that “continued exploration into advanced delivery systems and synergistic combinations will be essential to fully harness rutin's potential in photoprotection." Collaborative efforts between researchers and industry professionals will be crucial in overcoming existing challenges and bringing effective, sustainable sunscreen products to market.                                                                                             

Source: Cosmetics​
2024​, 11, 141. https://doi.org/10.3390/cosmetics11040141​ 
"Would Rutin be a Feasible Strategy for Environmental-Friendly Photoprotective Samples? A Review from Stability to Skin Permeability and Efficacy in Sunscreen Systems." 
Authors: Ariede, M.B. et al.