Discovery of steroidal alkaloid metabolites and their accumulation in pigs after short-term tomato consumption.

Studies suggest steroidal alkaloids contribute to the health properties of tomato-rich diets. Untargeted studies have detected tomato steroidal alkaloid metabolites in plasma, tissues, and urine, but concentrations remain unknown. Here we utilize UHPLC-MS/MS to characterize 31 steroidal alkaloid metabolites representing 10 unique masses, and a validated UHPLC-MS method to quantify them in blood plasma.

Carotenoid extraction and analysis from blood plasma/serum.

Accurate and sensitive methods to quantify carotenoids in blood plasma/serum are the basis for assessing carotenoid intake and associating physiological effects. This chapter introduces carotenoid chemistry, an overview of carotenoid food sources, and current knowledge of carotenoid absorption and metabolism, along with factors that affect these processes. We also detail a commonly used method to extract plasma/serum carotenoids using liquid-liquid extraction and analysis by high performance liquid chromatography coupled with diode array detection (HPLC-DAD).