Almond (Prunus dulcis (Mill.) D.A. Webb) polyphenols: From chemical characterization to targeted analysis of phenolic metabolites in humans

10 páginas, 3 figuras, 3 tablas.-- El pdf del artículo es la versión de autor.In this paper, a survey of our studies on almond polyphenols including their chemical characterization and further bioavailability in humans is reported. Combination of analytical techniques (LC-DAD/fluorescence, LC/ESI-MS and MALDI-TOF-MS) allowed us, for the first time, the identification of A- and B-type procyanidin, propelargonidin and prodelphinidin polymers in almond skins. Glucuronide, O-methyl glucuronide, sulfate and O-methyl sulfate derivatives of (epi)catechin, as well as the glucuronide conjugates of naringenin and isorhamnetin, and sulfate conjugates of isorhamnetin, together with conjugates of hydroxyphenylvalerolactones were detected in plasma and urine samples after the intake of almond skin polyphenols. In addition, numerous microbial-derived metabolites, including hydroxyphenylpropionic, hydroxyphenylacetic, hydroxycinnamic, hydroxybenzoic and hydroxyhippuric acids were also identified. Depending of the type of metabolite, maximum urinary excretion was attained at different time in comparison to the control group in the course of the 24-h period of urine excretion, allowing us to establish the onset of microbial metabolism.This work has received financial support from the CONSOLIDER INGENIO 2010 Programme: FUN-C-FOOD CSD2007- 063 from the Spanish Ministry of Science and Innovation (MICINN). I.G. was the recipient of a fellowship from the I3P Program funding by the European Social Fund. M.U.-S. thanks the FPI fellowship from MICINN. M.M. thanks the ‘‘Ramón y Cajal” post-doctoral program. R.L.L. thanks the ‘‘Fondo de Investigación Sanitaria” postdoctoral program (F.I.S. CD06/00161) from MICINN.Peer reviewe