Not only would these materials be more sustainable to produce, but they could also reduce the adverse side effects associated with synthetic sunscreens, such as contact sensitivity and estrogen mimicking, says Peyman Derikvand of the University of Isfahan.
Cyanobacteria are a particularly promising source of sunscreen ingredients because they can live in extremely arid climates and cope with both high ultraviolet radiation and extreme desiccation. Potential cyanobacteria-based ingredients include mycosporine-like amino acids and scytonemin, which provide strong screening protection from longwave and shortwave ultraviolet radiation respectively. Such photoprotectants could be effective alternatives to synthetic ultraviolet filters.
In addition, extracellular polymeric substances from cyanobacterial were found to retain moisture better than synthetically produced EPS, including urea, glycerin, and propylene glycol.
The research was published recently in the European Journal of Phycology and undertaken in collaboration with researchers in Swansea and London.