Naglaa A. Hafiz’s scientific contributions

Background and Objective: The cornerstone management options for tyrosinemia treatment are tyrosine and phenylalanine low diet, plus nitisinone (2-[2-nitro-4-trifluoromethylbenzoyl]-1,3-cyclohexanedione) (NCTB). Tyrosine ammonia lyase (TAL) converts tyrosine to harmless metabolites, i.e., P-coumaric acid and ammonia. This study aims to produce functional foods using tyrosine ammonia-lyase enzyme (TAL) for tyrosinemia treatment through feeding of female mice as animal model. Material and methods: Extracted TAL enzyme was used to treat egg white and mushroom flour to produce functional foods for tyrosinemia treatment. These functional foods were used to examine their effectiveness on food quality by estimation of color characteristics and determination of tyrosine concentrations. Moreover, determination the levels of tyrosinemia related-genes expression and DNA damage were carried out. Results: This study found that treated egg white and mushroom flour with TAL enzyme were stable in color. Tyrosine reduction percentages in female mice fed Tal-enzyme treated egg white and Tal-enzyme treated mushroom flour were 72.3% and 30.96%, respectively, compared with untreated diets using tandem mass spectrometry. In addition, the expression levels of tyrosine aminotransferase (TAT) and 4-Hydroxyphenylpyruvate dioxygenase (HPD) genes were remarkably elevated in mice feeding on TAL- egg white than other groups. Also, the DNA damage rate in mice fed on TAL – egg white showed lowest was decreased significantly compared with other groups. Conclusion: Addition of TAL enzyme reduced tyrosine to egg white and mushroom flour could be utilized and applied as functional food for tyrosinemia treatment regimes.