This project proposes the development of analytical methods using LC-MSn and LC-SPE-NMR that allows the differentiation of different species of Phyllanthus through the structural elucidation of secondary metabolites.The analysis will be performed by LC-MSn because of high sensitivity, mass separation power of the mass spectrometer and the possibility of structural elucidation without requiring isolation of secondary metabolites. However, data obtained by the fragmentation of precursor ions, often are insufficient for structure determination. Thus, the LC-SPE-NMR is used as an additional technique to LC-MSn due to the possibility to complete structural elucidation, especially when employed two-dimensional spectroscopy as HSQC, HMBC and COSY. Both techniques allow rapid analysis and low consumption of solvents.The genus Phyllanthus was chosen because of its extensive use in Brazilian folk medicine, being used mainly in cases of renal diseases and urolithiasis. The genre also has great taxonomic complexity, which makes its botanical identification laborious and subject to misinterpretation. In contrast, methods for quantification of chemical markers are usually not very effective in the standardization of plant species, given the wide variation in chemical constitution of plant extracts because of environmental and biological conditions.Thus, it is hoped that this study provides important structural information about the different chemical markers present in species of Phyllanthus amarus, P. caroliniensis, P. niruri, P. stipulatus and P. tenellus, providing a complete characterization of chemical species in order to establish quality standards to ensure high quality herbal products.
News published in Agência FAPESP Newsletter about the scholarship: