Metabolomic approaches to explore chemodiversity in seeds of guaraná (Paullinia cupana) using UPLC-QTOF-MSE and NMR analysis

Abstract

The growing interest in health and well-being has spurred the evolution of functional foods, which provide enhanced health benefits beyond basic nutrition. Guaraná seeds (Paullinia cupana) have been widely studied and used as a functional food due to their richness in caffeine, phenolic compounds, amino acids, and other nutrients. This has established guaraná as a significant food supplement, with Brazil being the largest producer of the world. This study aims to propose a set of analytical methods to chemically evaluate fifty-six different guaraná clones, from the Guaraná Germplasm Active Bank, to accommodate the diverse requirements of the food industry. Metabolomic approaches were employed, in which a non-target metabolomic analysis via UPLC-QTOF-MS^E led to the annotation of nineteen specialized metabolites. Furthermore, targeted metabolomics was also used, leading to the identification and quantification of metabolites by NMR. The extensive data generated were subjected to multivariate analysis, elucidating the similarities and differences between the evaluated guaraná seeds, particularly concerning the varying concentration levels of the metabolites. The metabolomics approach based on the combination of UPLC-QTOF-MS^E, NMR and chemometric tools provided sensitivity, precision and accuracy to establish the chemical profiles of guaraná seeds. In conclusion, evaluating and determining the metabolic specificities of different guarana clones allow for their application in the development of products with different levels of specific metabolites, such as caffeine. This caters to various purposes within the food industry. Moreover, the recognized pharmacological properties of the annotated specialized metabolites affirm the use of guarana clones as an excellent nutritional source.