Silk Protein UV Protection: A Natural Shield for Your Skin

Introduction to UV Protection by Silk Proteins

Silk proteins, particularly sericin and fibroin, have been recognized for their numerous skincare benefits, including their potential for UV protection. Derived from the cocoon of the silkworm Bombyx mori, these proteins offer a natural alternative to synthetic UV filters. Sericin, the outer layer of silk protein, forms a protective barrier on the skin, promoting hydration and providing a shield against UV radiation[1][2]. This blog explores the chemical mechanisms behind sericin’s UV protection, the markers used to test its effectiveness, and how it compares to other common UV protective ingredients.

The Chemical Mechanism by Which Sericin Exhibits UV Protection

Sericin exhibits UV protection through several key mechanisms:

1. UV Absorption: Sericin has the ability to absorb UV radiation, particularly in the UVB range, which is responsible for causing sunburn and contributing to skin cancer. This absorption helps to protect the skin from direct UV damage[1][2].
2. Antioxidant Properties: Sericin is rich in amino acids that exhibit strong antioxidant properties. These antioxidants help neutralize free radicals generated by UV exposure, reducing oxidative stress and preventing cellular damage[3][4].
3. Film-Forming Ability: Sericin forms a protective film on the skin’s surface, enhancing its barrier function. This film not only helps in UV protection but also in retaining moisture, which further contributes to its protective effects[4][5].

Markers Used to Test Silk Protein’s Effectiveness as UV Protection

The effectiveness of silk proteins as UV protectants is measured using several markers:

1. Sun Protection Factor (SPF): SPF measures the level of protection a sunscreen offers against UVB rays. It is calculated based on the ratio of the time it takes for UVB radiation to cause sunburn on protected skin versus unprotected skin[6].
2. Protection Grade of UVA (PA): PA measures protection against UVA rays, which penetrate deeper into the skin and are responsible for premature aging. The PA rating is indicated by the number of “+” signs, with more “+” signs indicating higher protection[6].
3. In Vitro and In Vivo Testing: In vitro testing involves using spectrophotometric methods to measure the absorbance of UV radiation by the sunscreen product. In vivo testing involves applying the sunscreen to human skin and exposing it to UV radiation to observe the time taken for erythema (redness) to develop[6].

Common Ingredients Used as UV Protection and Their Flaws

Several common ingredients are used for UV protection, each with its own set of advantages and disadvantages:

1. Chemical Filters (e.g., Octylmethoxycinnamate): These ingredients absorb UV radiation but can sometimes cause skin irritation and are less stable under prolonged UV exposure[7].
2. Physical Filters (e.g., Zinc Oxide, Titanium Dioxide): These ingredients provide broad-spectrum protection by reflecting and scattering UV radiation. However, they can leave a white cast on the skin, which is less desirable in cosmetic formulations[7].
3. Herbal Oils (e.g., Olive Oil, Peppermint Oil): These oils offer some level of UV protection but are generally less effective than specialized UV filters and silk proteins, with SPF values typically ranging from 1 to 8[8].

How Does Silk Protein Compare to These Common Ingredients?

Silk proteins, particularly sericin, offer several advantages over traditional UV protective ingredients:

1. Natural and Gentle: Unlike chemical filters, sericin is a natural ingredient that is less likely to cause skin irritation. Its gentle nature makes it suitable for sensitive skin[1][2].
2. Broad-Spectrum Protection: Sericin provides both UVB and UVA protection, similar to physical filters, but without the undesirable white cast[3][4].
3. Additional Skin Benefits: Beyond UV protection, sericin offers antioxidant properties, enhances skin hydration, and forms a protective barrier, making it a multifunctional ingredient in skincare formulations[1][2][4].

While direct comparisons can vary based on formulation and concentration, research indicates that silk proteins, particularly sericin, can offer UV protection comparable to traditional ingredients like zinc oxide and titanium dioxide. For instance:

• Zinc Oxide and Titanium Dioxide: These physical filters provide broad-spectrum protection and are highly effective, but they can leave a white cast on the skin. Their SPF values can range from 15 to 50, depending on concentration.
• Sericin: Studies have shown that sericin can provide significant UV protection, with SPF values in the range of 15 to 30 when used in appropriate concentrations. Additionally, sericin’s antioxidant properties and film-forming ability enhance its protective effects beyond mere UV absorption.[8]

Examples of Companies Using Silk Protein in UV Protection

Several companies have recognized the benefits of sericin and have incorporated it into their UV protection products:

• Shiseido: Known for its innovative skincare solutions, Shiseido includes sericin in some of its sunscreen formulations, leveraging its protective and moisturizing properties[1].
• Estée Lauder: This global beauty brand uses sericin in its products to enhance skin protection and hydration[1].
• L’Oréal: L’Oréal has integrated sericin into its sun care products to boost their effectiveness and skin benefits[1].
• Co-Luxury: Their Sunconor Blue Light & UV Protection Lotion with SPF 50 PA includes silk protein extracts to maintain skin moisture levels and provide effective UV protection[7].

Conclusion

Silk proteins, particularly sericin, offer a natural and effective means of UV protection, comparable to or even exceeding some traditional UV filters in terms of stability and additional skin benefits. Talk to us for procuring quality sericin for your UV Skin Products!

Citations:
[1] https://www.herbaldynamicsbeauty.com/blogs/herbal-dynamics-beauty/skincare-benefits-of-silk-protein
[2] https://www.jetir.org/papers/JETIR1810165.pdf
[3] https://www.sciencedirect.com/science/article/abs/pii/S1381514821001346
[4] https://www.dsm.com/personal-care/en_US/products/skin-bioactives/sericin.html
[5] https://boltthreads.com/technology/silk-protein/
[6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10003638/
[7] https://cocompany.in/products/co-luxury-sunconor-blue-light-uv-protection-lotion-with-matte-finish-spf-50-pa

[8] https://www.mdpi.com/2079-6412/7/9/145