title: Phenylketonuria: protein content and amino acids profile of dishes for phenylketonuric patients. The relevance of phenylalanine.
abstract: Phenylketonuria is an inborn error of metabolism, involving, in most cases, a deficient activity of phenylalanine hydroxylase. Neonatal diagnosis and a prompt special diet (low phenylalanine and natural-protein restricted diets) are essential to the treatment. The lack of data concerning phenylalanine contents of processed foodstuffs is an additional limitation for an already very restrictive diet. Our goals were to quantify protein (Kjeldahl method) and amino acid (18) content (HPLC/fluorescence) in 16 dishes specifically conceived for phenylketonuric patients, and compare the most relevant results with those of several international food composition databases. As might be expected, all the meals contained low protein levels (0.67-3.15 g/100 g) with the highest ones occurring in boiled rice and potatoes. These foods also contained the highest amounts of phenylalanine (158.51 and 62.65 mg/100 g, respectively). In contrast to the other amino acids, it was possible to predict phenylalanine content based on protein alone. Slight deviations were observed when comparing results with the different food composition databases.
authors.affiliation: REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia da Universidade do Porto, Rua de Jorge Viterbo Ferreira n.° 228, 4050-313 Porto, Portugal.
authors.forename: Filipa B
authors.initials: FB
authors.lastname: Pimentel
authors.forename: Rita C
authors.initials: RC
authors.lastname: Alves
authors.forename: Anabela S G
authors.initials: AS
authors.lastname: Costa
authors.forename: Duarte
authors.initials: D
authors.lastname: Torres
authors.forename: Manuela F
authors.initials: MF
authors.lastname: Almeida
authors.forename: M Beatriz P P
authors.initials: MB
authors.lastname: Oliveira
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000032:analysis* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004032:Diet / Q000592:standards*; D005504:Food Analysis; D006801:Humans; D010649:Phenylalanine / Q000032:analysis* / Q000378:metabolism; D010661:Phenylketonurias / Q000178:diet therapy / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D010649:Phenylalanine
keywords: Amino acids; Low protein foods; Phenylalanine; Phenylketonuria; Protein content