Carnosic acid (salvin) is abundant in sage and rosemary leaves. It has antioxidative, anti-carcinogenic, anti-inflammatory, anti-microbial, anti-adipogenic, antiproliferative, antitumorigenic and neuroprotective properties. It is increasingly exploited within food, nutrition health, and cosmetic industries. It is used as the main active antioxidants of food additives in Europe, in products including oils, animal fats, sauces, bakery wares, meat, and fish products etc. to prevent oxidation and prolong their storage time. It is proven to be efficient in the treatment of hyperglycemia. In cosmetic industry, it is used in the hair care and skin care products. Oral health care is another cosmetics-related application of carnosic acid: in vitro studies have shown that it efficiently protected against typical cariogenic microorganisms. It is the important raw material of tooth grinding and gargle agent.
(1) Antibacterial effect Studies have shown that carnosic acid has different inhibitory effects on Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Hansenula, and can be used as a food preservative.
(2) Antioxidant effect The carnosic acid has a good free radical scavenging and antioxidation effect. Its DPPH, ABTS free radical scavenging ability and iron reduction antioxidant capacity are stronger than VE, slightly weaker than synthetic antioxidant TBHQ; its reducing ability is stronger than VE and TBHQ. Carnosic acid is fat-soluble, which can effectively inhibit the formation of peroxides and the decomposition of polyene fatty acids, thereby prolonging the shelf life of fats and oils. In addition, it was found that carnosic acid can effectively eliminate oxygen free radicals in mouse hepatocytes, reduce the production of lipid peroxides, and stabilize cell membranes; carnosic acid can also inhibit the oxidation of low-density lipoprotein, which can effectively prevent The occurrence of atherosclerosis.