LC-MS Analysis and Quantification of Plants Apocarotenoids

Carotenoid oxidative cleavage products (apocarotenoids; APOs) represent an important class of specialized metabolites that exert diverse and important biological functions. Apocarotenoids are precursors of the plant hormones abscisic acid and strigolactones, pigments such as crocin and picrocrocin, and volatiles such as β-ionone and β-cyclocitral. Recently, carotenoid-derived bioactive metabolites such as zaxinone, anchorene, β-cyclocitral, and retinal have been identified as plant root growth regulators. Analysis of plant APOs is crucial for elucidating their biological function and metabolism as well as for determining their content in food. In this chapter, we describe an efficient protocol for a simultaneous analysis of plant APOs utilizing ultra-high performance liquid chromatographic (UPLC) separation and tandem mass spectrometry (MS). Additionally, we introduce practical details to assist researchers in setting up their experiments, extraction, and analysis of APOs.