Plants produce secondary metabolites that interact with human skin biology at a molecular level:
: Terpenoids found in essential oils can damage the cell walls of harmful microbes, serving as natural alternatives to synthetic preservatives. Key Herbal Ingredients & Their Uses Herbal Principles in Cosmetics
: Extracts like green algae ( Chlorella vulgaris ) inhibit metalloproteinases (enzymes that break down collagen) and stimulate new collagen synthesis. Herbal Principles in Cosmetics
: Phenolic compounds (like those in olive oil and pomegranates) contain benzene ring structures that act as natural UV filters . Herbal Principles in Cosmetics