One of the most important functions of the skin is to protect against various stressors. Environmental stimuli such as UV and environmental pollution increase reactive oxygen species and cause wrinkles and skin aging. Skin aging is associated with decreased collagen production and decreased activity of enzymes involved in collagen structure. Moisturizing chemicals increase the skin's ability to retain water, but long-term use can have adverse effects on human skin, such as allergies and even tumorigenic effects. As a result, the use of biological resources, especially photosynthetic organisms such as cyanobacteria, as safe alternatives is increasing. The mechanism by which cyanobacteria respond to ultraviolet radiation is the synthesis of ultraviolet compounds such as mycosporin-like amino acids and scytonemin. In addition, the exopolysaccharides produced by some species that live in extremely dry habitats can be used as moisturizers in cosmetics. In this study, we introduce the potential of cyanobacterial metabolites as alternative sources for sunscreens and moisturizers.
