Unfractionated extracts from twenty-five colored and uncolored Zea mays kernel landraces collected in Colombia were characterized according to tristimulus colorimetry parameters (L, C and h), antioxidant capacity (DPPH●, ABTS●+ and FRAP), total phenolic, flavonoids and anthocyanins contents (TPC, TFA and TAC, respectively), and RP-HPLC-MS-DAD analysis. Good correlations were found between TPC values and antioxidant capacity. All chemical data were also correlated using multivariate analysis in order to observe chemical variations and identify patterns. The multivariate analyses on quantitative and antioxidant activity data of all landraces separately resulted in differentiation regarding chemical data and origin. In addition, the clustering on chromatographic data using chemometrics was found to be correlated with quantitative values, antioxidant capacity, color and origin, indicating metabolite variability among extracts. The results therefore indicated that chemical composition can be considered a crucial factor to differentiate landraces as well as determine their variability regarding relative metabolite contents. TPC values and isoquercetin and cyanidin malonylglucoside relative contents were found to be the most discriminating factors among landraces. The present work constitutes the first study focused on chemical profiling combined with multivariate analysis as a tool for discriminating colored Zea mays kernels.
Key words: Anthocyanins, Antioxidants, Multivariate Data Analysis, Phenolics, HPLC-DAD-MS