Turkiye Klinikleri Journal of Health Sciences

.: ORIGINAL RESEARCH
Determination of Protein Quality of Products Used in Amino Acid Metabolism Diseases with Protein Digestibility-Corrected Amino Acid Score Method: A Descriptive Cross-Sectional Research
Amino Asit Metabolizması Hastalıklarında Kullanılan Ürünlerin Protein Kalitesinin Protein Sindirilebilirliği Düzeltilmiş Amino Asit Skoru Yöntemi ile Belirlenmesi: Tanımlayıcı Kesitsel Araştırma
Özge AKGÜNDOĞDUa , Elif EDE ÇİNTESUNa
aİstanbul Sabahattin Zaim University Faculty of Health Sciences, Department of Nutrition and Dietetics, İstanbul, Türkiye
Turkiye Klinikleri J Health Sci. 2025;10(3):584-92
doi: 10.5336/healthsci.2025-109371
Article Language: EN
Full Text
ABSTRACT
 Objective: The aim of this study was to evaluate the protein quality of products used in the nutritional treatment of phenylketonuria (PKU) and maple syrup urine disease (MSUD). Material and Methods: Protein digestibility corrected amino acid score (PDCAAS) method was used to evaluate protein quality. Thirty two products including 14 PKU Specialty Products, 5 PKU-glycomacroeptide (PKU-GMP) products and 13 MSUD products were analyzed. Results: PDCAAS scores of PKU products were between 94-100%; PDCAAS scores of PKU-GMP products were between 35- 99%. In general, the limiting amino acids were the sulfur amino acid group with 11 products. The PDCAAS score of MSUD products was between 24-49% and the limiting amino acids of these products were commonly sulfurous amino acid group. Conclusion: Present study revealed that the protein quality and PDCAAS value of PKU specialty products (except PKU-GMP) were generally high. PDCAAS value of PKU-GMP specialty products differed among themselves. The differences between PDCAAS value of PKU-GMP specialty products may attributed to the variability of amino acids supplemented in the products. In MSUD products, protein quality and PDCAAS value were generally lower than PKU specialty products (except PKU-GMP), which related to the limitation of valine, isoleucine, and leucine. Studies on therapeutic foods developed against congenital amino acid disorders are limited; further studies are needed.

Keywords: Phenylketonuria; maple syrup urine disease; congenital metabolic disorders; protein digestibility corrected amino acid score; protein quality
ÖZET
 Amaç: Bu çalışmanın amacı, fenilketonüri [Phenylketonuria (PKU)] ve akçaağaç şurubu idrar hastalığı [Maple Syrup Urine Disease (MSUD)] beslenme tedavisinde kullanılan ürünlerin protein kalitesinin değerlendirilmesidir. Gereç ve Yöntemler: Protein kalitesinin değerlendirilmesinde protein sindirilebilirliği düzeltilmiş amino asit skoru [Protein Digestibility Corrected Amino Acid Score (PDCAAS)] yöntemi kullanılmıştır. On dört PKU Özel Ürünü, 5 PKU-glikomakroeptit (PKU-GMP) ürünü, 13 MSUD ürünü olmak üzere 32 ürün incelenmiştir. Bulgular: PKU ürünlerinin PDCAAS skoru %94-100 arasında; PKU-GMP ürünlerinin PDCAAS skoru %35-99 arasında bulunmuştur. Genel olarak sınırlayıcı amino asitleri 11 ürün ile sülfürlü amino asit grubu olmuştur. MSUD ürünlerinin PDCAAS skoru %24-49 arasında bulunmuştur ve bu ürünlerin sınırlayıcı amino asitleri yaygın olarak sülfürlü amino asit grubu olmuştur. Sonuç: Mevcut çalışma, PKU özel ürünlerinin (PKU-GMP hariç) protein kalitesinin ve PDCAAS değerinin genel olarak yüksek olduğunu ortaya koymuştur. PKU-GMP özel ürünlerinin PDCAAS değeri kendi aralarında farklılık göstermiştir. PKU-GMP özel ürünlerinin PDCAAS değerleri arasındaki farklılıklar, ürünlere eklenen amino asitlerin değişkenliğine bağlanabilir. MSUD ürünlerinde protein kalitesi ve PDCAAS değeri, valin, izolösin ve lösin sınırlamasıyla ilişkili olarak PKU özel ürünlerinden (PKU-GMP hariç) genellikle daha düşüktür. Konjenital amino asit bozukluklarına karşı geliştirilen terapötik gıdalar üzerine çalışmalar sınırlıdır; daha fazla çalışmaya ihtiyaç vardır.

Anahtar Kelimeler: Fenilketonüri; akçaağaç şurubu idrar hastalığı; doğuştan metabolizma bozuklukları; protein sindirilebilirliği düzeltilmiş amino asit skoru; protein kalitesi
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