Collagen - an Essential Structural Protein, Underestimated Potentials and "Legendary Myths".

Collagen is one of the key structural proteins in the human body, playing an essential role in the mechanical stability and hydration of the skin. In the dermis, it forms a resilient scaffold that not only provides tensile strength but also serves as an interaction matrix for extracellular matrix cells such as dermal fibroblasts. In cosmetic formulations, collagen is typically used in hydrolyzed or native form, derived from animal sources such as calf, pig, or fish. Native collagen is characterized by its triplehelical a-chain structure, distinct telopeptide regions, and its ability to form supramolecular assemblies - features that are essential for its biological activity. In parallel with the growing demand for vegan cosmetics, plantbased alternatives are increasingly marketed under the label "vegan collagen." Biochemically these are not natural collagen molecules but rather collagen analogues or boosters. They include biotechnologically produced collagen-like proteins, plant extracts or synthetic peptides that stimulate collagen synthesis, or structurally related molecules intended to mimic collagen's functional properties. These analogues differ fundamentally in their molecular organization, particularly in terms of origin, glycosylation, telopeptide structure, and supramolecular behaviour. The terminological proximity to animal-derived collagen can lead to misinterpretation and highlights the need for clear definitions. A precise biochemical differentiation is therefore essential - both in scientific discourse and consumer communication - to realistically assess product claims and meet regulatory standards. [ABSTRACT FROM AUTHOR]