Caracterização de compostos fenólicos livres e ligados em frutos nativos (guabijú, guabiroba e araçá) por cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS)

• Ano de defesa: 2024
• Autor(a) principal: Machado, Patrícia Gotardo
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; Brasil; Ciência e Tecnologia dos Alimentos; UFSM; Programa de Pós-Graduação em Ciência e Tecnologia dos Alimentos; Centro de Ciências Rurais
• Palavras-chave em Português: Frutos nativos; Compostos fenólicos; Capacidade antioxidante; Espectrometria de massas; Cromatografia líquida; Quimiometria; Native fruits; Phenolic compounds; Antioxidant capacity; Mass spectrometry; Liquid chromatography; Chemometrics; CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS
• Link de acesso: http://repositorio.ufsm.br/handle/1/33305

The guabijú (Myrcianthes pungens), guabiroba (Campomanesia xanthocarpa), and araçá (Psidium cattleianum) are native fruits belonging to the Myrtaceae family and are part of Brazil's vast biodiversity of native species that are still underexplored. Determining the phenolic compounds present in these fruits is essential, as these compounds offer numerous benefits to human health. Moreover, investigating the phenolic compounds bound to matrix components, which in many studies are overlooked due to their extraction and analysis complexities, will provide the scientific community with novel and highly relevant nutritional information. Therefore, the main objective of the present study was to extract, separate, identify, and quantify the free and bound phenolic compounds present in the native fruits guabijú, guabiroba, and araçá, evaluating each part of the fruit, peel, pulp, and seed, separately. Fruits from different locations, harvest seasons, and even different genotypes, such as the red and yellow genotypes of araçá, were analyzed. The identification and quantification of the phenolic compounds were carried out using liquid chromatography coupled with mass spectrometry, employing quadrupole-time of flight and triple quadrupole mass analyzers (LC-ESI-QTOF-MS/MS and LC-ESI-QqQ-MS/MS), respectively. It was observed that guabijú has a wide variety of phenolic compounds, with eighty-one compounds identified tentatively and eighteen nonanthocyanin compounds and six anthocyanins quantified using analytical standards. Additionally, when assessing the fruit's maturation stages, it was found that these compounds exhibit distinct individual behaviors throughout the ripening process. For guabiroba, sixty-two compounds were tentatively identified, and fifteen were quantified with the aid of analytical standards. In the case of araçá, fourteen phenolic compounds were quantified in both fruits, and five anthocyanins were found in the peels and pulps of the red genotype, which outperformed the yellow genotype in the free phenolic fraction. However, the yellow genotype surpassed the red in the bound fractions. For all fruits, it was possible to observe a high in vitro antioxidant capacity through the hydrophilic ORAC method, and when correlated with the quantified phenolic compounds, positive correlations were obtained, indicating that they influenced the antioxidant capacity. The importance of evaluating bound phenolic compounds was also highlighted, as these fractions, often ignored in many studies, were where the highest concentrations of phenolic compounds were found in this study. Exploring knowledge about native fruits, in addition to providing novel data to the literature and filling gaps as demonstrated in this research, also promotes their consumption, adds value, and encourages further research and product development by the food, chemical, and pharmaceutical industries.