Carnosic Acid and Carnosol: Analytical Methods for Their Determination in Plants, Foods and Biological Samples

Abstract

Among the various phytochemicals, which are present in Lamiaceae plants, carnosic acid and carnosol stand out. Carnosic acid is a phenolic diterpene carrying two phenolic hydroxyl groups and a carboxyl group, while carnosol carries a lactone moiety in addition to phenolic hydroxyls. Both these phenolic diterpenes exhibit interesting biological properties, such as antioxidant, anticancer, anti-inflammatory and neuroprotective activities. In this review, we summarize the existing analytical methods for the determination of carnosic acid and carnosol, primarily in plants, but also in foods and biological samples. Due to the biological importance of carnosic acid and carnosol, a variety of analytical methods, including high-performance liquid chromatography–ultra violet (HPLC–UV), liquid chromatography–mass spectrometry (LC–MS) and capillary electrophoresis (CE), were developed for their determination. In addition, we discuss the extraction methods applied for their isolation from plants and in brief the bioactivities of these phytochemicals.