Discrimination of genotype and geographical origin of black rice grown in Brazil by LC-MS analysis of phenolics

Physicochemical properties, cooking time, and phenolics profile of two black rice genotypes grown at six different locations in Brazil were determined. The cultivar IAC 600 and the elite-line AE 153045 were used. The main growing locations for black rice were considered, as follows: Alegrete (ALG), Capao do Leao (CPL), Guaratingueta (GUA), Roseira (ROS), Santa Vitoria do Palmar (SVP), and Taubate (TBT). Principal component analysis (PCA) and supervised partial least squares-discriminant analysis (PLS-DA) from liquid chromatography-mass spectrometry (LC-MS) data sets showed distinction among genotypes and locations. Quercetin-3-O-glucoside and vanillic acid were the most relevant compounds for discriminating genotypes. SVP location provided the most distinctive black rice, with greater total phenolics content. Characteristics of black rice from SVP location were associated to effects of latitude and wind conditions. Hesperetin, vanillic acid, quercetion-3-O-glucoside, and p-coumaric acid were the most relevant compounds for discriminating locations.