Isol. from Salvia officinalis (sage) and Rosamarinus officinalis (rosemary). Dried leaves of rosemary or sage contain 1.5 to 2.5% carnosic acid. Carnosic acid is used as a preservative or antioxidant in food and nonfood products (e.g. toothpaste, mouthwash and chewing gum -in which it has an antimicrobial effect on the microbes responsible for bad breath- or skin care products).