Lilian Regina Barros Mariutti
University of Campinas, Brazil
Title: Carotenoids and carotenoid esters from fruits: strategies for identification by LC-MS
Biography
Biography: Lilian Regina Barros Mariutti
Abstract
Carotenoids are yellow to red liposoluble pigments found in plants, animals and microorganisms. The health benefits of the carotenoids have been attributed mainly to their antioxidant properties, which would minimize the in vivo oxidative damages induced by reactive oxygen (ROS) and nitrogen species (RNS). Their basic structure is a tetraterpene with a series of conjugated double bounds, and they can be divided into two main groups: carotenes (composed only of carbon and hydrogen atoms) and xanthophylls (contain at least one oxygen atom). Xanthophylls possessing hydroxyl groups can be found in nature acylated to several fatty acids, generating the carotenoid esters. The fact that a single carotenoid can be found acylated in several different combinations with distinct fatty acids further increases the variability of structures that can be found and the complexity of the analyzed matrix. Due to the high number of possible carotenoid esters in fruits and since all the esters of the same free carotenoid present exactly the same UV-visible spectrum, their identification must include tandem mass spectrometry (MSn) studies. Therefore, separation of carotenoids in reversed-phase liquid chromatography using C30 columns in combination with DAD and APCI-MS/MS detection allows high sensitivity and selectivity and is the technique of choice for carotenoid identification in complex matrices. Sample preparation and strategies for the identification of carotenoids and carotenoid esters based on UV-vis, MS and MS/MS spectra will be presented and discussed.