Rosemary extract as a natural source of bioactive compounds

Abstract

Rosemary (Rosmarinus officinalis, L.) is an aromatic evergreen herb widely used around the globe as a spice/seasoning, flavoring agent and for medicinal applications. Rosemary extract derived from rosemary leaves contains several polyphenolic components which exhibit antioxidant properties, but the predominant active components are the phenolic diterpenes, namely, carnosic acid and carnosol. Over 90% antioxidant activity of rosemary extract is attributed primarily to high content of lipophilic antioxidant molecules such as carnosic acid and carnosol. In addition to antioxidant components, rosemary extract also contains some volatile compounds. Rosemary extract bioactive compounds are also responsible for their distinctive aroma, color and flavor attributes. Rosemary extract can be applied in a wide range of oils and fats, and lipid-containing foods to delay lipid oxidation and to enhance the shelf-life of various food, feed and pet food products. This review delineates the chemistry, antioxidant mechanism, volatile flavor compounds, regulatory position, food applications, and stability of rosemary extract in foods.