Plantas alimentícias não convencionais (PANC) como alternativa dietética para fenilcetonúricos.

Abstract

Phenylketonuria is an autosomal recessive inborn error in the amino acid phenylalanine (Phe) metabolism caused by gene variants encoding phenylalanine hydroxylase. The main form of treatment is dietary Phe restriction, associated with using protein substitutes and low-protein foods such as fruits and vegetables, making the diet monotonous. Considering the incredible biodiversity of Brazil, studies that explore this potential, with the indication of new plant food options, such as Unconventional Food Plants (UFP), which may contribute to the diversification and supplementation of these patients' diets, become attractive. In this context, the objective was to select and characterize UFP with low protein content (< 5%), quantifying the Phe content. Fifteen UFP samples were selected, distributed in nine botanical families and 12 species. Of which 11 are leafy (almeirão-de-árvore, azedinha, bertalha, capiçoba, capuchinha, jambu, ora-pro-nóbis com e sem espinho, peixinho, taioba, vinagreira-roxa), one fruit (chuchu-de-vento), one flower (capuchinha), one sepal (vinagreira) and one stalk (taioba). At first, these samples were characterized by chemical composition and minerals. It was observed representative contents of the minerals potassium, calcium, magnesium, and iron, as well as contents of soluble fibers. The content of total phenolic compounds, the antioxidant capacity, and the chemical profile before and after the samples' in vitro gastrointestinal digestion process were also evaluated. The results showed relevant levels of total phenolic compounds and antioxidant capacity compared to some conventional vegetables. Regarding the chemical profile, it was possible to identify compounds from different chemical classes, emphasizing the class of flavonoids with the highest number of identified compounds. Furthermore, it was found that there was a difference in the constitution of these compounds before and after the digestion process. A chromatographic method using high-performance liquid chromatography with an ultraviolet detector (HPLC/UV) was validated in two matrices to determine the Phe content of the UFP samples. The performance parameters (linearity, selectivity, matrix effect, limit of detection and quantification, recovery, repeatability, and intermediate precision) studied in the validation indicated the method's suitability for quantification of Phe in plant matrix. Regarding the Phe content of the samples, it was observed that the leafy samples had a higher Phe content in the fruit, flower, sepal, and stem samples. The data presented in the study indicate that the UFP samples are suitable for use in the diet of patients with phenylketonuria. Thus, including these vegetables in the treatment can help with dietary diversity and nutrient intake, making them less monotonous and more palatable.