Use of infrared and mass spectrometry for the discrimination of metabolites from different stages of Schinus terebinthifolia Raddi leaves

The Brazilian Peppertree (Schinus terebinthifolia Raddi) is a medicinal plant with several biological activities, the most important of which are anti-inflammatory, antimicrobial and antiproliferative. Therefore, scientific research and investigation of its bioactive compounds are required. Leaves at three development stages were collected from three different genotypes of S. terebinthifolia. Methanol extracts were prepared and analyzed by infrared and mass spectrometry. The data obtained were treated by principal component analysis (PCA). The PCA model applied to the mass spectrometry data proved to be efficient to discriminate the three stages of development, in addition to indicating a differentiated tendency in the production of secondary metabolites by the genotypes. Two principal components were needed to describe the variance of the infrared spectrometry data (81.96%), while for mass spectrometry data three principal components were needed (55.73%). Ten substances were the most influential in the separation of the groups (young, intermediate, and old leaves or differentiation between genotypes A, B, and C), with emphasis on methyl digallate, quinic acid hexoside, digallic acid, and methyl gallate. Infrared spectroscopy data allowed us to differentiate young leaves from intermediate ones and the spectral bands that most influenced this differentiation (related to the groups O–H, C–O, CC, C–H and CO) correlated with the substances indicated by mass spectrometry. These results showed a different distribution of compounds among the leaf development stages, providing valuable information for those aiming to isolate specific substances of biological interest.