Sugarcane to skin: Lignin BB cream offers UV-antioxidant multifunctional promise

Writing in the International Journal of Biological Macromolecules​​, researchers from Portugal investigated the potential of lignin extracted from sugarcane bagasse – the dry pulpy fibrous material that remained after crushing sugarcane to extract juice – for use as an active skin care ingredient. The study incorporated the ingredient into a blemish balm (BB) cream.

‘Remarkable’ UV potential and ‘distinctive’ antioxidant activity​

“Lignin has been suggested as a promising candidate for cosmetic applications due to its remarkable potential to absorb ultraviolet rays and distinctive antioxidant activity,” ​the researchers wrote.​

The study, therefore, aimed to evaluate the performance of lignin extracted from sugarcane bagasse as a “natural UV blocker, antioxidant, and pigment”, ​they said.

Both in vitro and in vivo findings showed “notable results”​ of its biological potential, with the lignin ingredient offering broad-spectrum UV protection and scavenging potential that was preserved after incorporation into the BB cream cosmetic formulation.

This dual promise, the researchers said, was particularly relevant. “Human skin exposure to UV radiation results in a cascade of biochemical reactions, including depletion of antioxidant enzymes, thus causing a dramatic increase in the production of reactive oxygen species (ROS) associated to skin ageing, pigment darkening and even skin cancer. Therefore, compounds with the capacity to prevent or reduce ROS production and, simultaneously, protect from UV radiation are of prime interest for skin care products.”​

Importantly, the antioxidant activity and UV protection was achieved without any irritation or safety issues with lignin from sugarcane, the researchers said. Cytotoxicity, mutagenicity, skin sensitisation and allergy patch tests were conducted, proving the ingredient to be safe and suitable.

“Based on our findings, we conclude that SCB lignin has tremendous potential as a multifunctional candidate for colour cosmetics,”​ the researchers wrote.

‘Sun protection is arguably one of the most important steps of skin care’​

The researchers said this study was especially timely as sun care offerings became increasingly diversified, with many BB creams, foundations and moisturising creams offering UV protection in some form or other.

“Sun protection is arguably one of the most important steps of skin care,”​ the researchers said. And as the safety of some UV filters was currently being discussed – in terms of human health and environmental health – it was therefore important to investigate potential of other compounds.

For lignin, there was already “clear, strong and well-documented data”​ supporting the potential to use this compound as a natural antioxidant and UV blocker, from a variety of different biomasses, they said.

For the purposes of this study, lignin had been integrated at 5 wt% into the BB cream formula.

Source: International Journal of Biological Macromolecules​
Published online ahead of print, doi: 10.1016/j.ijbiomac.2023.123592​​
Title: “From sugarcane to skin: Lignin as a multifunctional ingredient for cosmetic application”​
Authors: F. Antunes et al.