Natural Bioactives for Skin Therapeutics: Cydonia oblonga and Cyanobacteria-Based Approaches

Abstract

Scytonemin, a lipid-soluble indole-alkaloid pigment synthesized by certain cyanobacteria, has emerged as a potent natural UVscreening compound with strong antioxidant and antiinflammatory properties. Its unique chemical structure enables absorption across a broad UV spectrum, particularly in the UVA range, making it highly effective in preventing oxidative damage and photoaging. This chapter explores the mechanisms of UV protection offered by scytonemin and the various strategies for its integration into topical skin formulations. Special emphasis is placed on nanoemulsion-based delivery systems, which improve solubility, enhance dermal penetration, and ensure stability. By combining natural photoprotective efficacy with advanced formulation technologies, scytonemin offers a promising alternative to conventional synthetic sunscreens, aligning with the growing demand for sustainable, biocompatible skincare solutions. The chapter also addresses formulation parameters, safety profiles, and regulatory considerations, paving the way for the development of next-generation cosmeceuticals rooted in nature and supported by science.