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A powerful HPLC-DAD-ESI-TOF MS method was established for the efficient identification of the chemical constituents in the methanolic extracts of avocado (Persea americana). Separation and detection conditions were optimized by using a standard mix containing 39 compounds belonging to phenolic acids and different categories of flavonoids, analytes that could be potentially present in the avocado extracts. Optimum LC separation was achieved on a Zorbax Eclipse Plus C18 analytical column (4.6×150 mm, 1.8 μm particle size) by gradient elution with water+acetic acid (0.5%) and acetonitrile as mobile phases, at a flow rate of 1.6 mL/min. The detection was carried out by ultraviolet-visible absorption and ESI-TOF MS. The developed method was applied to the study of 3 different varieties of avocado, and 17 compounds were unequivocally identified with standards. Moreover, around 25 analytes were tentatively identified by taking into account the accuracy and isotopic information provided by TOF MS.

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The phenolic fraction of monovarietal virgin olive oils (VOOs) from the main Moroccan cultivar Picholine marocaine (142 samples from three different subareas of the Meknès region) was studied over three consecutive crop seasons (2011, 2012, and 2013) using a powerful LC-MS methodology. First, LC-ESI-TOF MS was used to get a comprehensive characterization of the phenolic fraction; afterward, LC-ESI-IT MS was utilized for further identification (MS/MS experiments) and quantitation purposes. A total of 28 phenolic compounds (and quinic acid) were determined, revealing the complex profile of Meknès VOO, composed, in order of abundance, by secoiridoids, phenolic alcohols, lignans, flavonoids, and phenolic acids. Tukey's test was applied to ascertain possible significant intraregional and/or interannual variations of the phenolic content of the Meknès VOOs under study. Results showed that the content of phenolic compounds was mainly related to the crop season.

A library for GC-APCI-QqToF is now publicly available online.

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